cssi/SciSciGPT-SciSciNet huggingface dataset:
Catalysis by 18 + δ Compounds. Cyclooligomerization of Acetylenes Catalyzed by Co(CO)3L2

The ability of 18 + δ complexes to act as homogeneous catalysts was tested by studying the cyclooligomerization reactions of alkynes using the Co(CO)3L2 complex as the catalyst (L2 = 2,3-bis(diphenylphosphino)maleic anhydride). Cyclotrimerization occurred for RC⋮CR, where R = Ph, CH2OSiMe3, and CO2Me. No reaction was observed for R = H, CH3, SiMe3, or CH2CH2CH3. It is proposed that the alkynes need to be activated with electron-withdrawing groups to prevent the formation of high-energy 19-electron reaction intermediates. Although the mechanistic data are not conclusive, it is proposed that the reactions follow an odd-electron pathway involving the interconversion of 17- and 19-electron species. The 18 + δ complexes are labile to ligand dissociation, and it is this feature that makes them potentially good catalysts. The importance of ligand lability was demonstrated by comparing the activity of the Co(CO)3L2 complex to that of its inert 18-electron counterpart, Co(CO)3L2+; the 18-electron molecule was not ...
Understanding the one-photon photophysical properties of a two-photon absorbing chromophore

A comprehensive one-photon photophysical study has been carried out on AF455, a known two-photon absorbing dye. AF455 is composed of an electron-accepting center with three arms that consist of a π-conjugated group with an electron-donating group at the terminal end of each arm. The objective of this work is to understand the one-photon excitation photophysical properties so that this knowledge will be carried into understanding the two-photon absorption properties. This was done by utilizing steady-state absorption, steady-state and time-resolved emission, femtosecond pump−probe, and nanosecond laser flash photolysis techniques. Through this study it was determined that AF455 undergoes an excited-state intramolecular charge transfer (ICT) upon absorption of a single photon. The extent of ICT stabilization is dependent on the solvent polarity, with increasing ICT stabilization in more polar solvents. The formation of the triplet excited state is small (<8%) and is effected only slightly by a change in the...
Synthesis of nanotubes via cationic polymerization of styrene and divinylbenzene

A simple method for the preparation of nanoscale fibers and tubes by the cationic copolymerization of divinylbenzene (DVB) and styrene (ST) is described.
Deaths from gallstones: Incidence and associated clinical factors

The purpose of this study was to determine the incidence of death as the initial manifestation of cholelithiasis. Records of patients who died or underwent cholecystectomy for gallstone-related disease at Duke University Medical Center between 1976 and 1985 were reviewed. Thirty patients died, six of whom (20%) had previous episodes of biliary pain and stone documentation. Twenty-four (80%) were asymptomatic (three with previous incidental diagnosis of cholelithiasis). Reason for admission included acute cholecystitis (nine), pancreatitis (eight), biliary pain (six), cholangitis (four), jaundice (one), and endocarditis (one). Three patients died of gallstone complications without surgical intervention; one patient had renal failure and two had septicemia. Other causes of death were: sepsis (seven patients), cardiac failure (six), pulmonary complications (four), renal failure (three), cerebrovascular accident (three), liver failure (two), pancreatitis (one), and gastrointestinal bleeding (one). During this period, 1731 cholecystectomies were performed without mortality. In this group, the patients were younger (50 +/- 8 years vs. 64 +/- 13 years, p less than 0.001), and had a lower incidence of cirrhosis (p less than 0.001) and diabetes (p less than 0.002). The sex ratio was inverted (p less than 0.001). This study demonstrates that death from gallstones is uncommon (three cases per year), as is death from their initial clinical manifestation (1.2%). The risk of death is two- and ninefold higher in patients with acute cholecystitis or acute pancreatitis. Age, cirrhosis, and diabetes are important determinants of outcome.
Urine calcium and volume predict coverage of renal papilla by Randall's plaque

Urine calcium and volume predict coverage of renal papilla by Randall's plaque. Background Renal papillary plaques are common in calcium stone formers. We hypothesized that plaque should increase directly with urine calcium excretion, and inversely with urine volume. To test this, we measured papillary plaque areas in both idiopathic calcium oxalate stone formers and nonstone formers and examined 24-hour urine data to identify significant correlations. Methods Fourteen stone formers and four nonstone forming controls underwent papillary mapping with flexible nephroscopy. For each papillum, representative still images and moving pictures expert group (MPEG) movies were used to identify plaque extent and papillary borders. The mean fractional plaque coverage for each polar region (upper, inter, lower) and per papillum was calculated. The relationship of the plaque coverage data to urine measurements was assessed with general multivariate linear modeling. Results Mean polar fractional plaque coverage was higher in the calcium oxalate stone formers (7.4% vs. 0.5%, P = 0.012) as was mean fractional plaque per papillum (7.6% vs. 0.6%, P = 0.011). When correlating mean polar plaque coverage to urine data, urine volume and calcium excretion were the only measurements with independent relationships to plaque ( P = 0.002, adjusted multiple R 2 = 0.521), with higher calcium and lower volume increasing coverage. The same relationships hold for mean plaque per papillum, except that urine pH also becomes an independent factor ( P = 0.001, adjusted multiple R 2 = 0.606). Conclusion Utilizing advanced digital video and endoscopic equipment, we have achieved the most accurate estimation of papillary plaque coverage to date. Our findings support the idea that urine volume and calcium are the main correlates of plaque coverage.
Distinguishing depression and anxiety in self-report: evidence from confirmatory factor analysis on nonclinical and clinical samples.

Psychologists believe that anxiety and depression self-report scales tap distinct constructs. This assumption was tested by using confirmatory factor analysis on mood data from nonclinical samples (K. S. Dobson, 1985a; I. H. Gotlib, 1984; J. Tanaka-Matsumi & V.A. Kameoka, 1986) and a clinical sample (J. Mendels, N. Weinstein, & C. Cochrane, 1972). These analyses provide evidence that anxiety and depression self-report scales do not measure discriminant mood constructs and may therefore be better thought of as measures of general negative mood rather than as measures of anxiety and depression per se.
Tools and workflow for structure elucidation of drug degradation products

Abstract Drug degradation prediction, chemical-based experiments, isolation and structure-elucidation techniques are all tools used to develop drug candidates. Structure elucidation often requires isolation, degradation chemistry, mass spectrometry and nuclear magnetic resonance spectroscopy. This article gives an overview of these state-of-the-art technologies being utilized in industry and how they are integrated in a workflow to facilitate structure determination of drug degradation products.
Vimentin regulates activation of the NLRP3 inflammasome

Activation of the NLRP3 inflammasome and subsequent maturation of IL-1β have been implicated in acute lung injury (ALI), resulting in inflammation and fibrosis. We investigated the role of vimentin, a type III intermediate filament, in this process using three well-characterized murine models of ALI known to require NLRP3 inflammasome activation. We demonstrate that central pathophysiologic events in ALI (inflammation, IL-1β levels, endothelial and alveolar epithelial barrier permeability, remodelling and fibrosis) are attenuated in the lungs of Vim(-/-) mice challenged with LPS, bleomycin and asbestos. Bone marrow chimeric mice lacking vimentin have reduced IL-1β levels and attenuated lung injury and fibrosis following bleomycin exposure. Furthermore, decreased active caspase-1 and IL-1β levels are observed in vitro in Vim(-/-) and vimentin-knockdown macrophages. Importantly, we show direct protein-protein interaction between NLRP3 and vimentin. This study provides insights into lung inflammation and fibrosis and suggests that vimentin may be a key regulator of the NLRP3 inflammasome.
Estimating the throughput of an exponential CONWIP assembly system

We consider a production system consisting of several fabrication lines feeding an assembly station where both fabrication and assembly lines consist of multiple machine exponential workstations and the CONWIP (CONstant Work-In-Process) mechanism is used to regulate work releases. We model this system as an assembly-like queue and develop approximations for the throughput and average number of jobs in queue. These approximations use an estimate of the time that jobs from each line spend waiting for jobs from other lines before being assembled. We use our approximations to gain insight into the related problems of capacity allocation, bottleneck placement and WIP setting.
Use of solid-state nanopores for sensing co-translocational deformation of nano-liposomes

Membrane deformation of nano-vesicles is crucial in many cellular processes such as virus entry into the host cell, membrane fusion, and endo- and exocytosis; however, studying the deformation of sub-100 nm soft vesicles is very challenging using the conventional techniques. In this paper, we report detecting co-translocational deformation of individual 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) nano-liposomes using solid-state nanopores. Electrokinetic translocation through the nanopore caused the soft DOPC liposomes (85 nm diameter) to change their shape, which we attribute to the strong electric field strength and physical confinement inside the pore. The experiments were performed at varying transmembrane voltages and the deformation was observed to mount up with increasing applied voltage and followed an exponential trend. Numerical simulations were performed to simulate the concentrated electric field strength inside the nanopore and a field strength of 14 kV cm−1 (at 600 mV applied voltage) was achieved at the pore center. The electric field strength inside the nanopore is much higher than the field strength known to cause deformation of 15–30 μm giant membrane vesicles. As a control, we also performed experiments with rigid polystyrene beads that did not show any deformation during translocation events, which further established our hypothesis of co-translocational deformation of liposomes. Our technique presents an innovative and high throughput means for investigating deformation behavior of soft nano-vesicles.
Learning with queries but incomplete information (extended abstract)

We investigate learning with membership and equivalence queries assuming that the information provided to the learner is incomplete. By incomplete we mean that some of the membership queries may be answered by “I don't know.” This model is a worst-case version of the incomplete membership query model of Angluin and Slonim. It attempts to model practical learning situations, including an experiment of Lang and Baum that we describe, where the teacher may be unable to answer reliably some queries that are critical for the learning algorithm.We present algorithms to learn monotone k-term DNF with membership queries only, and to learn monotone DNF with membership and equivalence queries. Compared to the complete information case, the query complexity increases by an additive term linear in the number of “I don't know” answers received. We also observe that the blowup in the number of queries can in general be exponential for both our new model and the incomplete membership model.
CD4+ T cell clones isolated from human renal cell carcinoma possess the functional characteristics of Th2 helper cells.

The underlying cause for the observed poor antitumor activity of lymphocytes resident, in situ, in freshly resected human renal cell carcinoma (RCC) is unknown. To examine the basis for this observation we evaluated 217 T cell clones established from 20 consecutive patients with renal cell carcinoma. Of these, 75% were CD4+, 22% were CD8+, and 3% were NK+. Cytotoxic T cell function of CD4+ and CD8+ T cell clones was assessed by antibody-induced triggering of the TcR/CD3 complex. Nearly 93% of the CD4+ clones possessed poor cytolytic activity defined as or = 50% killing. In all T cell clones tested, MHC nonrestricted killing against Daudi or K562 was not observed. Overall, 77% of the T cell clones isolated from patients with RCC in this study were characterized by poor antitumor cytotoxic function; only 22% of the clones displayed strong cytolytic activity. Clones with strong cytotoxic function were tested for cytotoxic function against autologous tumor. However, all clones tested demonstrated little to no tumoricidal activity against autologous tumor. These results indicate that cytolytic T cells, while present in RCC, are not effectively activated by tumor to express CTL function. The immunobiology of CD4+ T cell clones was further evaluated. Thirty-two CD4+ clones from seven patients revealed distinct patterns of cytokine production following TcR/CD3 activation. CD4+ clones could be divided into IL-2 nonproducers and IL-2 producers. A total of 27/32 clones did not produce IL-2 following activation and IFN-gamma production by IL-2 nonproducers was more than threefold less than that by IL-2 producers. However, no differences were found in the levels of IL-4, IL-6, GM-CSF, or TNF-alpha between the two groups. Antitumor cytotoxicity mediated by CD4+ clones did not correlated with cytokine production. These results demonstrate that among T cells resident in human RCC, the predominant type of lymphocyte population consists of noncytolytic helper CD4+ T cells capable of secreting IL-4, but importantly not IL-2, and low levels of IFN-gamma following activation, thus resembling murine Th2 cells. Only a minor contribution by Th0-like cells was observed (i.e., CD4+ clones capable of secreting IL-2, IL-4, and IFN-gamma following activation).(ABSTRACT TRUNCATED AT 400 WORDS)
A unique E1-E2 interaction required for optimal conjugation of the ubiquitin-like protein NEDD8

Ubiquitin-like proteins (UBLs), such as NEDD8, are transferred to their targets by distinct, parallel, multi-enzyme cascades that involve the sequential action of E1, E2, and E3 enzymes. How do enzymes within a particular UBL conjugation cascade interact with each other? We report here that the unique N-terminal sequence of NEDD8’s E2, Ubc12, selectively recruits NEDD8’s E1 to promote Ubc12~NEDD8 thioester formation. A peptide corresponding to Ubc12’s N-terminus (Ubc12N26) specifically binds and inhibits NEDD8’s E1, the heterodimeric APPBP1-UBA3 complex. The structure of APPBP1-UBA3-Ubc12N26 reveals conserved Ubc12 residues docking in a groove generated by loops conserved in UBA3s but not other E1s, explaining why this interaction is unique to the NEDD8 pathway. These studies define a novel mechanism for E1–E2 interaction and show how enzymes within a particular UBL conjugation cascade can be tethered together by unique protein-protein interactions emanating from their common structural scaffolds.
The electrostatic interaction between interfacial colloidal particles

The electrostatic interaction between charged, colloidal particles trapped at an air-water interface is considered using linearised Poisson-Boltzmann results for point particles. In addition to the expected screened-Coulomb contribution, which decays exponentially, an algebraic dipole-dipole interaction occurs that may account for long-range interactions in interfacial colloidal systems.
Plantar Medial Wounds Associated With Calcaneal Fractures

Background:Calcaneal fractures with open wounds are prone to soft tissue complications. We describe a particular subclass of open injury that occurs on the plantar surface of the foot, medial to the anterior process of the calcaneus, the plantar medial wound (PMW). The purpose of this study was to evaluate soft tissue healing and potential complications in open calcaneal fractures that have a PMW.Methods:We established the time to soft tissue healing and the status of the injured limb of 11 adults with 12 calcaneal fractures with a PMW. This was a retrospective review of prospectively gathered data at a Level I trauma center.Results:Five fractures developed an infection requiring intravenous antibiotics. Two patients required split thickness skin grafts and 1 patient required a free gracilis flap 10 months after injury to treat a chronic open PMW with resolving osteomyelitis and required a below-knee amputation secondary to flap failure. The most commonly associated bony injury with a PMW was a transcalca...
Using optical markers of nondysplastic rectal epithelial cells to identify patients with ulcerative colitis-associated neoplasia.

Background: Current surveillance guidelines for patients with long-standing ulcerative colitis (UC) recommend repeated colonoscopy with random biopsies, which is time-consuming, discomforting, and expensive. A less invasive strategy is to identify neoplasia by analyzing biomarkers from the more accessible rectum to predict the need for a full colonoscopy. The goal of this pilot study was to evaluate whether optical markers of rectal mucosa derived from a novel optical technique, partial-wave spectroscopic microscopy (PWS), could identify UC patients with high-grade dysplasia (HGD) or cancer (CA) present anywhere in their colon. Methods: Banked frozen nondysplastic mucosal rectal biopsies were used from 28 UC patients (15 without dysplasia and 13 with concurrent HGD or CA). The specimen slides were made using a touch prep method and underwent PWS analysis. We divided the patients into two groups: 13 as a training set and an independent 15 as a validation set. Results: We identified six optical markers, ranked by measuring the information gain with respect to the outcome of cancer. The most effective markers were selected by maximizing the cross-validated training accuracy of a Naive Bayes classifier. The optimal classifier was applied to the validation data yielding 100% sensitivity and 75% specificity. Conclusions: Our results indicate that the PWS-derived optical markers can accurately predict UC patients with HGD/CA through assessment of rectal epithelial cells. By aiming for high sensitivity, our approach could potentially simplify the surveillance of UC patients and improve overall resource utilization by identifying patients with HGD/CA who should proceed with colonoscopy. (Inflamm Bowel Dis 2011)
Phosphate Starvation Responses and Gibberellic Acid Biosynthesis Are Regulated by the MYB62 Transcription Factor in Arabidopsis

The limited availability of phosphate (Pi) in most soils results in the manifestation of Pi starvation responses in plants. To dissect the transcriptional regulation of Pi stress-response mechanisms, we have characterized the biological role of MYB62, an R2R3-type MYB transcription factor that is induced in response to Pi deficiency. The induction of MYB62 is a specific response in the leaves during Pi deprivation. The MYB62 protein localizes to the nucleus. The overexpression of MYB62 resulted in altered root architecture, Pi uptake, and acid phosphatase activity, leading to decreased total Pi content in the shoots. The expression of several Pi starvation-induced (PSI) genes was also suppressed in the MYB62 overexpressing plants. Overexpression of MYB62 resulted in a characteristic gibberellic acid (GA)-deficient phenotype that could be partially reversed by exogenous application of GA. In addition, the expression of SOC1 and SUPERMAN, molecular regulators of flowering, was suppressed in the MYB62 overexpressing plants. Interestingly, the expression of these genes was also reduced during Pi deprivation in wild-type plants, suggesting a role for GA biosynthetic and floral regulatory genes in Pi starvation responses. Thus, this study highlights the role of MYB62 in the regulation of phosphate starvation responses via changes in GA metabolism and signaling. Such cross-talk between Pi homeostasis and GA might have broader implications on flowering, root development and adaptive mechanisms during nutrient stress.
A multi-threaded approach to using asynchronous C libraries with Java

It is very common to write device drivers and code that access low level operation system functions in C or C+ +. There are also many powerful C and C++ libraries available for a variety of tasks. Java is a programming language that is meant to be system independent and is arguably much simpler to code than C/C++. However, Java has minimal support for talking to native libraries, which results in interesting challenges when using C/C++ libraries with Java code. Part of the problem is that Java's standard mechanism for communicating with C libraries, Java Native Interface, requires a significant amount of effort to do fairly simple things, such as copy structure data from C to a class in Java. This is largely solved by using the Java Native Access Library, which provides a reasonable way of transferring data between C structures and Java classes and calling C functions from Java. A more serious issue is that there is no mechanism for a C/C++ library loaded by a Java program to call a Java function in the Java program, as this is a major issue with any library that uses callback functions. A solution to this problem was found using a moderate amount of C code and multiple threads in Java. The Keck Task Language API (KTL) is used as a primary means of inter-process communication at Keck and Lick Observatory. KTL is implemented in a series or C libraries and uses callback functions for asynchronous communication. It is a good demonstration of how to use a C library within a Java program.
God, Freedom, and Pain

FOR many people the problem of evil is a major stumbling block to belief in God. A history professor asks, why did a good God permit Hitler to incinerate millions of Jews? A parishoner wants to know why his beloved wife must lie dying of cancer? A female Pepsis wasp plunges its stinger into its tarantula victim, injecting just enough venom to paralyze, but not to kill, the spider host, so that the wasp larvae may eat the living but helpless body. Why has the syphilis germ come to be in the course of the evolution of life? It lives, survives, and thrives only in higher organic hosts, which are its victims. Treat some kinds of bacterial disease with our modern "miracle drugs" and, in reaction to the medication, mutating genes produce new, hardier strains of the destructive microbe. Why is there pain especially when it seems "excessive," "prolonged" and "unnecessary"? If God is good and loving, and if His power is adequate, why is there physical and mental suffering in our world? If the evolutionary process is the divinely appointed, creative method, why has so much of it taken a course of brutality and aggression? Raising the question at the most fundamental level of process, why has evolution taken place by "mutations," many of which must be classified as "evil" when they result in the suffering of living forms? For many minds the fact of pain, and back of it, the phenomenon of "evil," or "inept" mutation remains the unhealed core of the problem of evil, and a barrier to religious faith. Theistic faith must make adequate reply to the inquiry of sincere doubt regarding pain, and one of its more obvious cosmic origins in what we here provisionally call "evil mutations." Facing the fact of pain in our world, are there rational grounds for belief in the loving goodness and the sufficient Power of a Creative Person?
Regulation of neural responses to emotion perception by ketamine in individuals with treatment-resistant major depressive disorder.

The glutamate N-methyl-D-aspartate receptor antagonist ketamine has demonstrated antidepressant effects in individuals with treatment-resistant major depressive disorder (TRD) within 24 h of a single dose. The current study utilized functional magnetic resonance imaging (fMRI) and two separate emotion perception tasks to examine the neural effects of ketamine in patients with TRD. One task used happy and neutral facial expressions; the other used sad and neutral facial expressions. Twenty patients with TRD free of concomitant antidepressant medication underwent fMRI at baseline and 24 h following administration of a single intravenous dose of ketamine (0.5 mg kg−1). Adequate data were available for 18 patients for each task. Twenty age- and sex-matched healthy volunteers were scanned at one time point for baseline comparison. Whole-brain, voxel-wise analyses were conducted controlling for a family-wise error rate (FWE) of P<0.05. Compared with healthy volunteers, TRD patients showed reduced neural responses to positive faces within the right caudate. Following ketamine, neural responses to positive faces were selectively increased within a similar region of right caudate. Connectivity analyses showed that greater connectivity of the right caudate during positive emotion perception was associated with improvement in depression severity following ketamine. No main effect of group was observed for the sad faces task. Our results indicate that ketamine specifically enhances neural responses to positive emotion within the right caudate in depressed individuals in a pattern that appears to reverse baseline deficits and that connectivity of this region may be important for the antidepressant effects of ketamine.
A comparison of adaptive belief propagation and the best graph algorithm for the decoding of linear block codes

In this paper, two iterative message passing algorithms based on belief propagation proposed for the decoding of any binary linear block code are compared. The innovation of these algorithms lies in the fact that the structure of the graph of the parity check matrix is adaptively modified to render it suitable to belief propagation decoding. The modification is done such that the least reliable bits received from the channel are leaves of the graph. These algorithms perform favorably when compared with existing hard and iterative soft decision decoding algorithms in terms of error rate while maintaining a complexity polynomial in block length. It was found that while these two algorithms are conceptually similar, their performance in terms of word error rate (as a function of signal-to-noise ratio), decoding time (average number of iterations) and the updated bit reliabilities are very different
The use of infrared dichroic absorption spectra in the study of the structure of bovine fibrinogen and fibrin.

Abstract Bovine fibrinogen and fibrin were examined by infrared spectroscopy both as films and in KBr media. In addition, the dichroic spectra of fibrin as an oriented film was studied. The infrared absorption spectra of bovine fibrinogen and fibrin were virtually identical in all major bands supporting the concept that there is no major conformational modification of the fibrinogen molecule during the clotting process. The presence of calcium ion caused observable frequency changes in the NH stretching modes of both bovine fibrinogen and fibrin suggesting interaction of calcium with the protein with a resultant change in the NH bond strength. The dichroic nature of oriented fibrin films is compatible with alpha-helix structure parallel to the major fibrin axis; although the possibility of some less common protein conformation is not precluded. The low experimental values of dichroic ratio are consistent with recent models proposed by other investigators.
A controlled outdoor test site for evaluation of soil effects on landmine detection sensors

Previous modeling studies and experimental work have demonstrated that soil physical properties have a significant effect on most sensors for the detection of buried land mines. While a modeling approach allows for testing of the effects of a wide range of soil variables, most experimental work is limited to (field) soils with poorly known or controlled properties. With this in mind, we constructed a new outdoor test site with full control of soil water content and continuous monitoring of important soil properties and environmental conditions. In three wooden frames of 2 x 2 x 1 meter, filled with different soil types (sand, loam, and clay), we buried low-metal anti-tank and anti-personnel land mine simulants. We installed time domain reflectometry (for measurement of soil water content) and temperature probes at different depths above and below the land mines as well as in homogeneous soil away from the land mines. In this paper we document the features of this new test site and present results from the monitoring equipment.
A Psychodynamic Approach to the Teaching of Writing: The Hermeneutic Dialogue

This article describes a method for teaching writing based on a psychodynamic theoretical orientation. Previous conceptualizations for teaching writing from a dynamic perspective are critically reviewed, and an alternative method, the hermeneutic dialogue, is introduced. With this method, writing is taught through an interpretive exchange between instructor and student. Difficulties using this method are explored as are the similarities and differences with other teaching methods. Two examples of how this method might be wed are presented.
Organics in optoelectronics: advances and roadmap

Over a four-year period from 2001 to 2005, the Microphotonics Center Industry Consortium at MIT evaluated the vast array of new technologies that have disrupted the telecommunications industry. As part of its mission, the consortium researched a variety of communications-related technical and business topics, presented recommendations for the rational restructuring of the industry, and developed a 30-year communications technology roadmap (CTR). The CTR program was guided by industry-led Technology Working Groups (TWGs), with the support of MIT faculty and students. We present the findings of the Organics in Optoelectronics TWG in terms of advances in organic-material based optoelectronic integrated circuits (OEICs), and we propose a roadmap for optoelectronic integration enabled by hybrid organic-inorganic OEICs.
Role of steroidal glycoalkaloid α-tomatine in host-plant resistance of tomato to colorado potato beetle

The role of the steroidal glycoalkaloid α-tomatine in the hostplant resistance of tomato to the Colorado potato beetle,Leptinotarsa decemlineata (Say) was examined in short- (24 hr; using first- and fourth-instar larvae) and long-term (first-instar larvae reared through the prepupal stage) feeding experiments. Consumption rate, growth rate, efficiency of conversion of ingested food to body mass, and survival were compared forL. decemlineata provided foliage from susceptible (Lycopersicon esculetum Mill. cv. Walter), resistant (L. hirsutum f.Glabratum C.H. Mull accession PI 134417), and F1 hybrid plants. Values obtained for dietetic indices were regressed against corresponding values for α-tomatine content of foliage provided to larvae. Differences in dietetic indices could not be attributed to variation in foliar α-tomatine content despite a long-standing literature showing theex planta α-tomatine inhibits feeding and growth byL. decemlineata.
Ascending projections from marginal zone (Lamina I) neurons of the spinal dorsal horn

A search for postsynaptic elements, excited only by slowly-conducting afferent fibers (Aδ and C), was made by recording from the dorsal horn of cats and monkeys with dye-filled microelectrodes. Units identified by afferent responsiveness were tested for antidromic invasion by electrical stimulation of the opposite ventrolateral funiculus at the midcervical level. Recording points were marked by iontophoretically passing dye from the recording electrode and subsequently located in histologically-prepared material. Evidence for antidromic excitation from spinal cord stimulation was found for five of 21 units in cat and 13 of 31 neurons in monkey. Antidromically excited cells were located within the distribution of the large posteromarginal neurons of the dorsal marginal zone (Lamina I). Although recording loci for a number of the elements studied were unequivocally located within Laminae II (substantia gelatinosa) or III, none could be antidromically excited. All antidromically driven units received a powerful input from Aδ primary afferent units and upon testing with natural stimuli responded specifically to stimuli of the type initiating activity either for high threshold mechanoreceptors or for low threshold thermoreceptors. It is concluded that some Lamina I neurons form part of an ascending projection which follows the spinal pathway of the spinothalamic tract and thereby contribute to the mechanical nociceptive and thermoreceptive features of this pathway. The absence of antidromic response is argued to be uncertain and evidence for a lack of projection is open to alternative explanation.
Focus points and naturalness in supersymmetry

We analyze focus points in supersymmetric theories, where a parameter's renormalization group trajectories meet for a family of ultraviolet boundary conditions. We show that in a class of models including minimal supergravity, the up-type Higgs mass parameter has a focus point at the weak scale, where its value is highly insensitive to the universal scalar mass. As a result, scalar masses as large as 2 to 3 TeV are consistent with naturalness, and all squarks, sleptons and heavy Higgs scalars may be beyond the discovery reaches of the CERN Large Hadron Collider and proposed linear colliders. Gaugino and Higgsino masses are, however, still constrained to be near the weak scale. The focus point behavior is remarkably robust, holding for both moderate and large $\mathrm{tan}\ensuremath{\beta},$ any weak scale gaugino masses and A parameters, variations in the top quark mass within experimental bounds, and for large variations in the boundary condition scale.
Rapid Reversion of Cell‐Division‐Factor Habituated Cells in Culture

Abstract The heritable conversion of cell-division factor (CDF)-requiring tobacco pith cells to the CDF-autotrophic state, known as CDF habituation, is a directed process that occurs at very high rates in culture. Here we show that tiny, leafy buds arising from habituated tissues placed on an inductive medium exhibit the non-habituated phenotype. The appearance of these buds was used to estimate the rate at which habituated cells revert. The rate obtained, approx. 4 × 10 -3 per cell generation, is at least 100 to 1,000 fold higher than expected for somatic mutation. Moreover, reversion is a directed process, i.e., it occurs at high rates only under conditions that promote bud formation. These findings provide compelling evidence that habituation of tobacco pith cells involves epigenetic changes rather than rare, random genetic mutations.
A single-layer metamaterial-based polarizer and bandpass frequency selective surface with an adjacent transmission zero

In this article, a high order bandpass miniaturized-element frequency selective surface (MEFSS) and a wire-grid polarizer are implemented on a single-layer substrate. This compact spatial filter and polarizer are designed to be incorporated in a 26 GHz UWB rangefinder radar. The spatial filter has a passband at 26 GHz and a transmission zero at 13 GHz. A new single-face miniaturized-element FSS has been proposed to produce the desired frequency response. An accurate circuit model has been developed for this structure to facilitate the filter synthesis process. The structure has been analyzed and optimized with a full-wave EM solver. A prototype of the designed structure has been fabricated and tested. Measurement results show low insertion loss in the passband (&#60;0.5 dB) and high rejection at transmission zero (>20dB).
Effect of screening tests on the lifetime statistics of injection lasers

Injection laser lifetime data are subjected to a simple screening test to identify the longer lived units. The effect this has on the lifetime distribution, and in particular, on the reliability of a system composed of a set of these lasers is considered.
Corporate Tax Avoidance and the Level and Valuation of Firm Cash Holdings

This paper examines the relation between corporate tax avoidance and firm cash holdings. Corporate tax avoidance limits payments made to the tax authorities. However, recent research notes that tax avoidance also restricts the flow of firm specific information and thereby exacerbates manager-shareholder conflict of interest. Specifically, it is argued that tax avoidance allows for greater rent extraction by managers. We examine this implication in relation to firm cash holdings. Cash is a fungible asset that can be easily diverted. To the extent that tax avoidance facilitates greater rent extraction, it will lead to a quicker dissipation of firm cash holdings. We empirically evaluate this prediction. To further evaluate the influence of tax avoidance, we also examine its impact on the valuation of firm cash holdings. If investors perceive tax avoidance as enabling diversion of firm resources, it should negatively impact their valuation of firm cash holdings. We provide three primary findings. First, we find a negative association between tax avoidance and firm cash holdings. We find this association to hold across multiple measures of tax avoidance. Second, we find this relation is attenuated for firms with stringent governance structures in place. This finding suggests stringent governance structures serve to limit the adverse effects of tax avoidance strategies. Finally, we find investor valuation of firm cash holdings is lower for firms with higher levels of tax avoidance. We again find this relation is attenuated for strong governance firms. Overall, our findings contribute to a growing stream of research which notes that tax avoidance is a double-edged sword which can cause more harm than good for shareholders.
Memory design for high temperature radiation environments

This paper presents bulk CMOS memory circuits capable of both ultra-low voltage (subthreshold, i.e., VDD less than the transistor threshold voltage Vth) low power operation and high temperature operation at nominal VDD. One of the memory designs is radiation hardened by design (RHBD) using interleaved DICE storage cells, enclosed transistor geometries, and P-type guard rings. The other is not hardened against radiation. Experimental results are presented showing that the room temperature minimum VDD of the hardened device remains essentially unchanged from the pre-irradiation VDDMIN = 210 mV value after Co-60 irradiation to 4 Mrad(Si). The standby power supply current ISB of the device increases less than 2x from this level of irradiation. The RHBD memory design has been tested to be operational at temperatures of 225degC. The combined effects of high temperature and irradiation are also investigated for both designs.
Petrographic and geochemical analysis of caliche profiles in a Bahamian Pleistocene dune

Two caliche profiles from a Pleistocene carbonate dune on San Salvador Island, Bahamas, were examined by petrographic and geochemical analysis. Profile A is an immature buried caliche profile characterized by caliche pisolites, a friable crust and abundant Cerion. Profile B is a more well-developed caliche profile at the top of the dune which contains abundant pisolites, rhizomorphs, laminated calcrete, a breccia and abundant Cerion. Geochemical changes in caliche profiles relative to the host rock are an increase in Al2O3, Fe2O3 and total organic carbon, a decrease in Mg and Sr, and a decrease in δ13Ccarb, δ18Ocarb and δ13Corg. The magnitude of these changes is probably a function of the duration of subaerial exposure and resultant colonization by dune plants and associated microflora. Abundance of calcified filaments and needle-fibre crystals in profile A attests to the importance of microbial processes in the early development of caliche profiles. Biogenic structures are largely destroyed in profile B due to recrystallization, but indirect evidence of biological activity is retained in the form of carbon isotope values.
Electron-Hop-Funnel Measurements and Comparison With the Lorentz-2E Simulation

Electron hop funnels have been fabricated using a low-temperature cofired ceramic. The measurements of the hop-funnel I-V curve and electron energy distribution have been made using gated field emitters as the electron source. The charged particle simulation Lorentz 2E has been used to model the hop-funnel charging and to predict the - and energy characteristics. The results of this comparison indicate that the simulation can be used to design hop-funnel structures for use in various applications.
The accelerated fully rough turbulent boundary layer

The behaviour of a fully rough turbulent boundary layer subjected to favourable pressure gradients both with and without blowing was investigated experimentally using a porous test surface composed of densely packed spheres of uniform size. Measurements of profiles of mean velocity and the components of the Reynolds-stress tensor are reported for both unblown and blown layers. Skin-friction coefficients were determined from measurements of the Reynolds shear stress and mean velocity.An appropriate acceleration parameter Kr for fully rough layers is defined which is dependent on a characteristic roughness dimension but independent of molecular viscosity. For a constant blowing fraction F greater than or equal to zero, the fully rough turbulent boundary layer reaches an equilibrium state when Kr is held constant. Profiles of the mean velocity and the components of the Reynolds-stress tensor are then similar in the flow direction and the skin-friction coefficient, momentum thickness, boundary-layer shape factor and the Clauser shape factor and pressure-gradient parameter all become constant.Acceleration of a fully rough layer decreases the normalized turbulent kinetic energy and makes the turbulence field much less isotropic in the inner region (for F equal to zero) compared with zero-pressure-gradient fully rough layers. The values of the Reynolds-shear-stress correlation coefficients, however, are unaffected by acceleration or blowing and are identical with values previously reported for smooth-wall and zero-pressure-gradient rough-wall flows. Increasing values of the roughness Reynolds number with acceleration indicate that the fully rough layer does not tend towards the transitionally rough or smooth-wall state when accelerated.
A Study of Oxygen Vacancy Formation and Annihilation in Submonolayer Coverages of TiO2 Dispersed on MCM-48†

The reduction and reoxidation of submonolayer coverages of TiO2 deposited onto MCM-48 were investigated. The deposited TiO2 was characterized by Raman and UV−visible spectroscopy. Raman spectra sho...
Reasoning about conditional sentences: Development of understanding of cues to quantification

The previous literature has reported that when children are asked to judge the truth or falsity of universally quantified conditional sentences of the form If a thing isPthen it isQ they typically give erroneous responses, e.g., responding “true” whenever there is a case of PandQ even if there are also cases of Pand not-Q. Three experiments are reported that address possible sources of this error. Experiment 1 shows that the error survives on sentences that refer to particular things as well as to things of a particular kind, and further shows that articulating the necessity of the consequent (… then it has to beQ) eliminates the error for adults and reduces it for fifth graders, although it does not affect second grade performance. Experiment 2 shows that for second and fifth graders the error survives to problems that are not universally quantified and for second graders to problems that are not conditionals although are otherwise structurally similar. Experiment 3 compares various verbal formulations of such universally quantified conditionals: Second and fifth graders do not make the error when the quantification is expressed with the surface structure that makes its universality most explicit (all things …); the error tendency is greatest when the indefinite article is used (if a thing …); and formulations using any fall in between. We argue that such erroneous evaluations of universally quantified conditionals have more to do with the quantificational aspect than the conditional aspect of the problems; children interpret the indefinite article as existential, although they resist the error when the cue to universal quantification is completely clear. The error appears to result more from the surface-structure form of the stimuli than from an inability of children to appreciate the logic of universally quantified conditionals.
Existence of Good Codes with Low Peak-to-Average Power Ratios for Multicarrier Communications

An appendum to a theorem of Shannon is proved. It is proved that that there exists asymptotically good codes of length n, whose peak-to-average power ratio for multicarrier communications is at most 8 log n.
The Independent Effects of Phonotactic Probability and Neighborhood Density on Lexical Acquisition by Preschool Children.

The goal of this research was to disentangle effects of phonotactic probability, the likelihood of occurrence of a sound sequence, and neighbourhood density, the number of phonologically similar words, in lexical acquisition. Two-word learning experiments were conducted with 4-year-old children. Experiment 1 manipulated phonotactic probability while holding neighbourhood density and referent characteristics constant. Experiment 2 manipulated neighbourhood density while holding phonotactic probability and referent characteristics constant. Learning was tested at two time points (immediate vs. retention) in both a naming and referent identification task, although only data from the referent identification task were analysed due to poor performance in the naming task. Results showed that children were more accurate in learning rare sound sequences than common sound sequences and this was consistent across time points. In contrast, the effect of neighbourhood density varied by time. Children were more accurat...
Dye-Sensitized TiO2 Solar Cells: Structural and Photoelectrochemical Characterization of Nanocrystalline Electrodes Formed from the Hydrolysis of TiCl4

The structure and photoelectrochemical properties of TiO2 films deposited onto SnO2 conducting glass from the ambient hydrolysis of TiCl4 and annealed at temperatures ranging from 100 to 500 °C were studied by Raman spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), intensity-modulated photovoltage spectroscopy (IMVS), and intensity-modulated photocurrent spectroscopy (IMPS) measurements. Analysis of the XRD and Raman spectra shows that TiCl4-produced TiO2 films have the rutile structure, regardless of annealing temperature. The TEM reveals that the rutile TiO2 films consist of rod-shaped particles that grow with increasing annealing temperature. The AM-1.5 short-circuit photocurrent Jsc and open-circuit photovoltage Voc of Ru[LL‘(NCS)2]-sensitized (L = 2,2‘-bypyridyl-4,4‘-dicarboxylic acid, L‘ = 2,2‘-bipyridyl-4,4-ditetrabutylammoniumcarboxylate) 4.5 μm thick rutile films increase significantly with annealing temperature, from 1.1 mA/cm2 and 602 mV at 100 °C to 8.7 mA/cm2 and ...