cssi/SciSciGPT-SciSciNet huggingface dataset:
Evaluating the perils and promises of academic climate advocacy

What are the causes and consequences of academic climate advocacy in contemporary times? Should it be celebrated and pursued, or derided and eschewed? Does advocacy in various forms tarnish or enhance the reputation of science? This research examined conditions whereby some in academic communities facilitate various forms of engagement relating to their research while others shy away from applications of their work and avoid the “advocate” label. Through an exploratory survey of US-based natural and social science climate researchers/scholars and through analysis of interviews of US-based climate change academic researchers/scholars as part of an “Inside the Greenhouse” and “More than Scientists” collaboration, we explored academic advocacy in a twenty-first century climate communications environment. Among our findings, there was broad agreement that climate change is a pressing issue, yet among social scientists, women are more likely to agree that advocacy should not be criticized than their male social scientist counterparts. Younger respondents were more likely than older respondents to be compelled to change by advocacy from someone with a smaller carbon footprint. Meanwhile, social scientists were more likely than natural scientists to be compelled to change by someone with a smaller carbon footprint. The associated effect of age differences was stronger than the associated differences with profession. Together, we examined these dynamic conditions that animate advocacy opportunities and tensions in the context of contemporary climate change research and engagement. Through conflation between advocacy for evidence-based climate science and advocacy for particular policy outcomes (with coincident dangers of individualism and apolitical intellectualism), we found that academic climate advocacy remains an unresolved subject.
Is susceptibility to E-cigarettes among youth associated with tobacco and other substance use behaviors one year later? Results from the PATH study.

Abstract E-cigarettes are the most commonly used tobacco product among youth. In addition to harm potential, e-cigarette use is associated with initiating cigarette smoking. Limited research exists whether susceptibility to e-cigarette use is a risk factor for future tobacco and other substance use initiation. This study examined associations between baseline e-cigarette susceptibility and initiation and past 30-day use of e-cigarettes and cigarettes as well as initiation of marijuana and alcohol one year later, after adjusting for other risk factors and sociodemographic confounders. The study sample consisted of 5156 nationally representative youth (12–17 years) who completed both waves 1 (2013–2014) and 2 (2014–2015) of the Population Assessment of Tobacco and Health (PATH) study and were never users of tobacco, marijuana, and alcohol in Wave 1. Youth who were susceptible to e-cigarettes had increased odds of initiating e-cigarettes (adjusted OR: 2.22, 95% CI: 1.55–3.18), marijuana (aOR: 1.66, 95% CI: 1.12–2.46), and alcohol (aOR: 1.61, 95% CI: 1.26–2.06) between waves, as well as past reporting 30-day e-cigarette use (aOR: 3.64, 95% CI: 1.93–6.89) in Wave 2. Additionally, cigarette susceptibility, but not e-cigarette susceptibility, was associated with cigarette initiation (aOR: 3.36, 95% CI: 1.95–5.82) and past 30-day use (aOR: 2.83, 95% CI: 1.34–5.97). Prevention policies, as well as future research, could target youth susceptible to e-cigarettes to reduce the current trends on the use of these alternative tobacco products. Such efforts may also reduce the use of cigarettes and other substances.
Effect of low‐temperature storage on the content of folate, vitamin B6, ascorbic acid, chlorogenic acid, tyrosine, and phenylalanine in potatoes

Background Changes in the metabolite composition of potato tubers during low-temperature storage can affect their nutritional value, susceptibility to bruising, and processing qualities. Here, we measured changes in the amounts of folate, vitamin B6 , and vitamin C, and the blackspot pigment precursors chlorogenic acid and tyrosine, as well as phenylalanine, in five potato varieties stored at 7.8 °C for 8 months in 2015 and 2016. Results Folate content increased in all varieties in both years during low-temperature storage, with statistically significant changes occurring in six out of eight conditions. Increase rates ranged from 11% to 141%. Vitamin B6 content increased in all varieties during the storage period, but changes were statistically significant in only two out of eight conditions. Increase rates ranged from 5% to 24%. Ascorbic acid content decreased in all varieties in both years during the storage period. Decrease rates ranged from 16% to 78%, and were statistically significant in seven out of eight conditions. For chlorogenic acid, no consistent trend was observed. Changes varied between -14% and +14%, but none was statistically significant. Tyrosine content increased in all varieties in both years, except in Sage Russet in 2015. Increase rates ranged from 19% to 238% and were statistically significant in three out of seven conditions. Changes in phenylalanine content were very similar to those observed for tyrosine, with increases up to 272% in Teton Russet. Conclusions These results show that storage at low temperature substantially affects tuber nutritional quality and biochemical bruising potential. © 2019 Society of Chemical Industry.
Dimensionally distributed learning models and algorithm

This paper introduces a framework for regression with dimensionally distributed data with a fusion center. A cooperative learning algorithm, the iterative conditional expectation algorithm (ICEA), is designed within this framework. The algorithm can effectively discover linear combinations of individual estimators trained by each agent without transferring and storing large amount of data amongst the agents and the fusion center. The convergence of ICEA is explored. Specifically, for a two agent system, each complete round of ICEA is guaranteed to be a non-expansive map on the function space of each agent. The advantages and limitations of ICEA are also discussed for data sets with various distributions and various hidden rules. Moreover, several techniques are also designed to leverage the algorithm to effectively learn more complex hidden rules that are not linearly decomposable.
Pancreas transplantation: Current issues, unmet needs, and future perspectives

Abstract The history of vascularized pancreas transplantation spans more than 50 years and largely parallels advances in clinical immunosuppression and surgical techniques. As of December 2017, more than 56,000 pancreas transplants were reported to the International Pancreas Transplant Registry (IPTR) including > 32,000 from the United States and > 24,000 from outside of the United States. Pancreas transplantation has been performed with a high and increasing level of success for 30 years. For simultaneous pancreas-kidney (SPK) transplant recipients with dual allograft function at 1 year, the conditional half-life of the pancreas graft currently averages 12–15 years. Many pancreas transplant recipients have been insulin-independent for > 10 years and some for > 20 years. In every update of the IPTR spanning 30 years, patient and graft survival rates in all three categories of pancreas transplantation have continued to improve whereas early technical and immunological graft losses have continued to decline. Recently published data have documented that since 1987, 79,198 life-years have been “saved” by SPK transplantation (4.6 life-years per recipient) and 14,903 life-years by solitary pancreas transplants (2.4 life-years per recipient) in the United States.
A logical layer protocol for activebus architecture

This research investigates several problems associated with current multiprocessor interconnection networks, focusing primarily on general-purpose, shared-memory configurations. The project deals with all aspects of the interconnection, from the architectural level to the physical backplane. A multiple-bus based architecture is presented as an alternative to the limitations of current schemes. This dissertation will focus on the logical layer specification. The ActiveBus--a multiple, active bus--interconnection is proposed. Multiple buses increase the bandwidth as well as reliability of the interconnection while the active backplane shows a reduced and uniform capacitive load. A logical layer protocol was designed for each bus to work independently, to achieve fault tolerance. Each bus uses a word-serial approach to keep the total number of bus signal lines manageable. A dual clocking scheme is proposed. The faster clock is used for data transfer. The other clock, refered to as sync clock, is used for arbitration and handshaking. Absence of discontinuities on the bus coupled with a source-synchronous transfer protocol allows data to be streamed at a high rate, thus increasing the pin-efficiency of the bus. The data transmission rate is limited only by clock skew. In addition, the ActiveBus interface unit and the source synchronous protocol move the synchronization penalty from the shared bus to the private buffer in the unit. The protocol uses a new arbitration scheme, termed Previous Priority First. This hybrid control acquisition scheme combines collision detection and priority arbitration to minimize bus access time without requiring additional signal lines. Collision detection provides a quick access in an unsaturated system while priority arbitration guarantees the deterministic election of the master in a saturated system. The scheme also incorporates a fairness mode to minimize starvation and bus access delay in the system. The cache coherence scheme supports both copy-back and write-through policies to reduce the overhead. MOESI protocol with snoopy caches, being the most general, is followed. Message passing and synchronization primitives are provided within the bus protocol to support multiple processor systems. These primitives attempt to minimize the traffic generated by the spin locks or the memory hot spots.
Detection of spin-orbit torque with spin rotation symmetry

It has been recently demonstrated that spin–orbit coupling in ferromagnetic metals can generate spin current with symmetries different from the conventional spin Hall effect in nonmagnetic metals. The generated spin current can induce a spin–orbit torque on a neighboring magnetic layer with spin rotation symmetry. In this paper, we introduce a set of tools to measure this effect in a perpendicularly magnetized film, by using the second-order planar Hall effect method and spin-torque ferromagnetic resonance spectroscopy. These results are comparable to those detected by the polar magneto-optic Kerr effect technique.
Predicting potential adverse events using safety data from marketed drugs

While clinical trials are considered the gold standard for detecting adverse events, often these trials are not sufficiently powered to detect difficult to observe adverse events. We developed a preliminary approach to predict 135 adverse events using post-market safety data from marketed drugs. Adverse event information available from FDA product labels and scientific literature for drugs that have the same activity at one or more of the same targets, structural and target similarities, and the duration of post market experience were used as features for a classifier algorithm. The proposed method was studied using 54 drugs and a probabilistic approach of performance evaluation using bootstrapping with 10,000 iterations. Out of 135 adverse events, 53 had high probability of having high positive predictive value. Cross validation showed that 32% of the model-predicted safety label changes occurred within four to nine years of approval (median: six years). This approach predicts 53 serious adverse events with high positive predictive values where well-characterized target-event relationships exist. Adverse events with well-defined target-event associations were better predicted compared to adverse events that may be idiosyncratic or related to secondary target effects that were poorly captured. Further enhancement of this model with additional features, such as target prediction and drug binding data, may increase accuracy.
Stabilization of Sn Anode through Structural Reconstruction of a Cu–Sn Intermetallic Coating Layer

The metallic tin (Sn) anode is a promising candidate for next-generation lithium-ion batteries (LIBs) due to its high theoretical capacity and electrical conductivity. However, Sn suffers from severe mechanical degradation caused by large volume changes during lithiation/delithiation, which leads to a rapid capacity decay for LIBs application. Herein, a Cu-Sn (e.g., Cu3 Sn) intermetallic coating layer (ICL) is rationally designed to stabilize Sn through a structural reconstruction mechanism. The low activity of the Cu-Sn ICL against lithiation/delithiation enables the gradual separation of the metallic Cu phase from the Cu-Sn ICL, which provides a regulatable and appropriate distribution of Cu to buffer volume change of Sn anode. Concurrently, the homogeneous distribution of the separated Sn together with Cu promotes uniform lithiation/delithiation, mitigating the internal stress. In addition, the residual rigid Cu-Sn intermetallic shows terrific mechanical integrity that resists the plastic deformation during the lithiation/delithiation. As a result, the Sn anode enhanced by the Cu-Sn ICL shows a significant improvement in cycling stability with a dramatically reduced capacity decay rate of 0.03% per cycle for 1000 cycles. The structural reconstruction mechanism in this work shines a light on new materials and structural design that can stabilize high-performance and high-volume-change electrodes for rechargeable batteries and beyond.
NOVELTIES IN BRAZILIAN BEGONIACEAE IV: Taxonomic notes

As a result of a taxonomic study on Begoniaceae from Brazil, nine new synonyms are proposed and two species are restored from synonymy. Eleven names are lectotypified and two are neotypified.
Pathways to Adolescent Emotional and Behavioral Problems: An Examination of Maternal Depression and Harsh Parenting

Abstract Background Maternal depression is linked with a range of child and adolescent outcomes. Prior research suggests adverse consequences for child and youth development, but less is known about the role of adverse parenting in the pathways from maternal depression to adolescent emotional and behavioral problems. Objective The present study leveraged a large, longitudinal survey of families across the U.S. to investigate whether harsh parenting mediated the links between maternal depression and adolescent delinquency and depression. Participants and setting Data came from a national longitudinal survey of families with children born in large U.S. cities 1998-2000 in which mothers had at least partial custody of children (N = 2,719). Methods Structural equation modeling with latent variables estimated a measurement model using confirmatory factor analysis and a structural model testing direct and indirect pathways. Results Maternal depression was directly associated with both physical and psychological aggression in parenting (β = 0.08, p Conclusions Findings provide insights into the parent-level drivers of adolescent emotional and behavioral outcomes. Screening for maternal depression and providing parenting support to vulnerable families offers promise for preventing adverse parenting and supporting healthy adolescent development.
TRAUMATIC BRAIN INJURY, THE GUT MICROBIOME, AND SOCIOECONOMIC STATUS: A REVIEW

This article reviews existing literature on three bidirectional relationships. These are traumatic brain injury (TBI) and gut microbiome relationship, the TBI and socioeconomic status (SES) relationship, and the gut microbiome and SES relationship. Literature on the relationship between TBIs and the gut microbiome underscores the loop created through the gut-brain axis, leading TBI to disrupt gut microbiota composition and diversity, which in turn aggravate existing neuroinflammation in the brain. Literature on the relationship between TBIs and SES links lower SES to higher occurrence rates of TBI and poorer recovery outcomes. Literature on the relationship between the gut microbiome and SES, links lower SES to gut dysbiosis, presenting as imbalanced gut microbiota composition and lower diversity. The TBI-gut microbiome, TBI-SES, and gut microbiome-SES bidirectional relationships reinforce health inequity and call for social justice advocacy for the protection of brain health of people of lower socioeconomic backgrounds.
Variation in heterotrophic and autotrophic nitrifier populations in relation to nitrification in organic soils.

The occurrence of heterotrophic and autotrophic nitrifiers in Pahokee muck and the role of these organisms in the ecosystem were assessed by surveying their population densities under different field conditions and by observing the relationship of these populations with aerobic bacteria and soil moisture. Heterotrophic nitrifier populations varied from 2.0 × 105 to 3.8 × 106 bacteria per cm3 of muck in surface fallow (bare) Pahokee muck during the annual cycle. This population decreased 40-fold between the surface and the 60- to 70-cm depths of soil. Similar variations were noted with autotrophic nitrifier populations. Significant correlations were found between heterotrophic nitrifiers and both soil moisture and aerobic bacteria. These relationships did not exist for the autotrophic nitrifiers. In soil that had been heated to kill the autotrophic nitrifiers, while preserving a population of the heterotrophs, and then amended with sodium acetate or ammonium sulfate or both, no nitrate or nitrite accumulated, although significant increases in heterotrophic nitrifiers were detected. In unheated control soil, nitrate plus nitrite-N increased from 14.3 to 181 μg/g of wet soil, and 48 μg of nitrite-N per g was produced. These data suggest that the autotrophic nitrifiers were the sole population responsible for nitrification in Pahokee muck.
Fifteen years of kidney biopsies in children: a single center in Egypt.

This study retrospectively investigates the indications and results of renal biopsy in children to determine the patterns of childhood kidney disease in a single tertiary children's hospital in Egypt. We included all the patients who underwent ultrasound-guided renal biopsy from 1998 to 2012. All the kidney biopsies were studied under light microscopy, while immunofluorescence and electron microscopy were performed when indicated. A total of 1246 renal biopsies were performed over 15 years, on 1096 patients. The mean age of the patients at the time of biopsy was 9.2 ± 3.7 years. The main indication for a biopsy was the steroid-resistant nephrotic syndrome (n = 354, 28.4%), followed by the atypical nephrotic syndrome (n = 250, 20.1%), and renal abnormalities in the systemic diseases (n = 228, 18.3 %). In the 1226 pathologically diagnosed specimens, primary glomerulonephritis was the most common finding (n = 826, 67.4%), followed by secondary glomerulonephritis (n = 238, 19.4%). The most common causes of primary glomerulonephritis were Minimal Change Disease (MCD) (n = 267, 21.8%), diffuse proliferative glomerulonephritis (n = 188, 15. 3%), and focal proliferative glomerulonephritis (n = 164, 13.3%). Lupus nephritis (n = 209, 17%) was the most common cause of secondary glomerulonephritis. We conclude that the steroid-resistant nephrotic syndrome was the most frequent indication for biopsy and minimal change disease was the most common histopathological finding in our population.
Apoptosis and Antiphospholipid Antibodies

In the early 1980s, a motley crew of itinerants strove to discover the cause of systemic lupus erythematosus (SLE) in Graham Hughes’ laboratory at the Hammersmith Hospital, London. The crew included myself, Azzudin Gharavi, Bernie Colaco and others. Having presented a stimulating paper by Robert Schwartz at a journal club demonstrating that some murine anti-DNA monoclonal antibodies cross react with phospholipids [1], Aziz, Bernie and I decided to test the same idea in human SLE and Graham decided to re-explore the clinical associations of anticardiolipin (aCL) autoantibodies. The resulting publications [2, 3] were a start and led to the subsequent collaboration between Aziz and Nigel Harris, development of the quantitative solid-phase immunoassay for antiphospholipid antibodies (aPL) that transformed the field.
On Proving Safety Properties by Integrating Static Analysis, Theorem Proving and Abstraction

We present a new approach for proving safety properties of reactive systems, based on tight interaction between static analysis, theorem proving and abstraction techniques. The method incrementally constructs a proof or finds a counterexample. Every step consists of applying one of the techniques and makes constructive use of information obtained from failures in previous steps. The amount of user intervention is limited and is highly guided by the system at each step. We demonstrate the method on three simple examples, and show that by using it one can prove more properties than by using each component as a stand-alone.
Behavioural modelling of analog circuits by dynamic semi-symbolic analysis

The paper presents an approach to behavioural modelling of analog circuits by dynamic semi-symbolic analysis, where some circuit parameters are kept as symbols and the others are given as numeric values. Our new method is based on the determinant decision diagram (DDD) representation of small-signal characteristics of linear analog circuits. The basic idea is to dynamically reorder DDD vertices such that all the DDD vertices corresponding to symbolic parameters are separated from DDD vertices for numerical parameters. In this way, DDD sizes of symbolic portion of DDD can be significantly reduced by suppressing numerical DDD nodes. Our new approach is different from the existing MTDDD based semi-symbolic analysis method where reordering is done before DDD is constructed and DDD-based graph operations are still valid in the new method. The proposed dynamic ordering algorithm, which is based on swap of adjacent variables, also improves the existing DDD-based vertex sifting algorithm as no special sign rule is required after DDD vertices are swapped. Experimental results have demonstrated that the proposed dynamic semi-symbolic method leads to up to 30% symbolic DDD node reduction compared MTDDD method on real analog circuits and can be performed very efficiently.
Space partitioning for privacy in location-based services continuous nearest neighbor query

With the help of location-aware mobile device user can issue a query and obtain information on nearest point of interest as it moves within a spatial network. This evolving computing paradigm offers great level of convenience to information access and usage. Nevertheless, the convenience comes with a price in the form of exposing user private information to potential abuse and misuse. This paper proposes a novel idea to protect user private information in a location-based services continuous nearest neighbor query with a focus on moving query and static object. Most proposed solutions for privacy use third party anonymizer, or offer protection only for snapshot query, however most queries are continuous. In this proposal we combine Voronoi tessellation and Hilbert curve order with R-tree index of geometric data storage to provide transition points that indicate where nearest neighbor changes. With a database arranged as a square matrix of size n bits, we execute double private information retrieval protocol in the server to return exact nearest neighbor point of interest throughout the query segment with minimal cost, and without revealing any user private information. Our experimental evaluation of the transmission cost using ns-3 simulator and the complexity analysis show a system capable of being scaled to different population size with minimal performance impact and with improvement on the complexity over related technique.
The pituitary-adrenal system and the developing brain.

Publisher Summary This chapter discusses evidence for the hypothesis that adrenal hormones may have a similar organizing effect on the developing central nervous system both with regard to neuroendocrine regulation of adrenocorticotropic hormone (ACTH) synthesis and release and with certain aspects of the behavior of adult organisms. An initial study discussed in the chapter reveals several interesting findings. The essence of these findings is that there is an extremely high level of adrenal activity in terms of both plasma and adrenal concentration of corticosterone in the newborn rat. There is also a clear and definitive response to administration of exogenous ACTH. However, following the initial period of high activity, there is a marked diminution of activity and the animal becomes unresponsive to ACTH and remains unresponsive until approximately 15 to 18 days of age. Pituitary ACTH increases markedly between 6 and 9 days of age. Adrenal corticosterone concentrations and plasma ACTH again appear at approximately 12 days of age, and by 15 days of age, the system appears to be totally active. In view of experimental data that were not compatible with the concept of an absolute stress non-responsive (SNR) period in the newborn, a series of investigations were undertaken to systematically investigate some of the parameters of the maturation of the organism's capacity to respond as indicated by significant changes in both plasma and adrenal corticoids, as well as in plasma and pituitary ACTH.
Mutations in an upstream regulatory sequence that increase expression of the bacteriophage T4 lysozyme gene.

Abstract A P22 hybrid phage bearing the bacteriophage T4 lysozyme gene (e), as well as T4 sequences upstream from the lysozyme gene, was constructed. Amber mutations were introduced into gene e in the hybrid phage, and the resulting mutant phages were tested for the ability to form plaques on amber suppressor strains. Revertant phages that were able to form plaques on amber suppressors that did not suppress the parent amber mutant phages were isolated following UV mutagenesis. Secondary site pseudorevertants were identified among the revertants by a genetic test. Four of the suppressing secondary site mutations were mapped and sequenced. They were found to consist of small sequence alterations immediately upstream from gene e, all of which would tend to destabilize potential base-pairing interactions in the transcript. The mutations were shown to increase lysozyme expression when introduced into an otherwise wild-type hybrid phage, but were found to have little effect on transcription of the lysozyme gene.
Net flux of amino acids across the portal-drained viscera and liver of the ewe during abomasal infusion of protein and glucose

The objective of the study was to measure net AA flux rates across the portal-drained viscera (PDV) and liver in the presence and absence of abomasal glucose infusion. Decreasing the fraction of AA metabolized by the mucosal cells may increase the fraction of AA being released into the blood. A potential mechanism to reduce AA catabolism by mucosal cells is to provide an alternative source of energy. We hypothesized that increasing glucose flow to the small intestine would increase net appearance of AA across the PDV. Eighteen mature ewes with sampling catheters were placed on study. The experimental design was a split-plot with a complete randomized design on the whole-plot and a Latin-square subplot with 5 periods and incremental levels of protein infusion. One-half of the ewes received abomasal glucose infusions (3.84 g/h), and all ewes received each of 5 protein abomasal infusion levels over 5 periods (0, 2.6, 5.2, 7.8, and 10.5 g/h). Net PDV release of isoleucine, leucine, methionine, phenylalanine, aspartate, glutamate, glutamine, proline, serine, and tyrosine increased linearly with increased protein infusion, and net PDV release of histidine, lysine, threonine, valine, alanine, and glycine did not differ with protein infusion. Net hepatic glucose release decreased with glucose infusion. With the exception of histidine, phenylalanine, and valine, net hepatic AA uptake increased linearly with increased delivery of AA to the liver. Glucose infusion increased the hepatic lysine and valine uptake and decreased phenylalanine uptake. Based on the observations in the current study, we reject our hypothesis that glucose can spare AA metabolism by PDV tissue. Our findings suggest that hepatic gluconeogenesis can be increased in the presence of increased AA delivery to the liver and that hepatic gluconeogenesis can be decreased with increased absorption of dietary glucose. Our findings support the concept that for most AA, hepatic transport of AA can be described by mass action kinetics; however, the rates of hepatic uptake of specific AA are upregulated directly or indirectly by elevated glucose.
Regeneration of Hyaline Cartilage Using a Mechanically-Tuned Chondrocyte-Seeded Biomimetic Tissue-Engineered 3D Scaffold: A Theoretical Approach

The limited ability of cartilage tissue to repair itself poses a functionally impairing health problem. While many treatment methods are available, full restoration of the tissue to its original state is rare. Often, complete joint replacement surgery is required to obtain long-term relief. Tissue engineering approaches, however, provide new opportunities for cartilage replacement. They seek to provide mechanisms to repair or replace lost tissue or function. A theoretical method is presented here for regenerating hyaline cartilage in vitro using a chondrocyte-seeded three-dimensional biomimetic engineered scaffold with mechanical properties similar to those occurring naturally. The scaffold composition, type II collagen, aggrecan, hyaluronan, hyaluronan binding protein (for link protein), and BMP-7, were chosen to encourage synthesis of hyaline cartilage by providing a more native environment and signaling cue for the seeded chondrocytes. The scaffold components mimic the macrofibrillar collagen network found in articular cartilage. Type II collagen provides tensile strength, and aggrecan, the predominant proteoglycan, provides compressive strength.
Die Diels‐Alder‐Reaktion in der Totalsynthese

In den letzten Jahrzehnten hat wohl keine andere Reaktion das Forschungsgebiet der Totalsynthese mehr gepragt als die Diels-Alder-Reaktion. Mit einer Vielzahl von Anwendungen dieser grosartigen pericyclischen Reaktion, oftmals als entscheidendes Element einer eleganten Kaskadenreaktion zur Herstellung komplexer Molekulstrukturen, ermoglichte die Diels-Alder-Cycloaddition die Losung einer Reihe unterschiedlicher, von der Natur in Form von Naturstoffen gestellter Syntheseprobleme. Zur Feier des hundertjahrigen Jubilaums von Alders Geburtstag soll dieser Aufsatz die ungemeine Leistungsfahigkeit der von ihm entdeckten Reaktion anhand ausgewahlter Beispiele im Kontext der Totalsynthese verdeutlichen und ihre Vielseitigkeit sowie ihr gewaltiges, noch immer nicht vollstandig erfasstes Potential unterstreichen.
Tensile recoil measurement of compressive strength for polymeric high performance fibres

Recoil forces acting on the broken ends of a fibre after tensile failure are known to cause substantial damage to polymeric high performance fibres. This damage is the result of compressive stresses developed during snap-back, or recoil, whose magnitude exceeds the compressive strength of the fibre. An analysis describing the axial stress history experienced by a fibre following a tensile failure has been performed and the results have led to the development of a simple, single filament, recoil technique for measuring fibre compressive strength. A number of polymeric high performance fibres were examined using the technique and compressive strengths measured are in excellent agreement with values obtained from composite tests.
Statistical line-by-line model for atomic spectra in intermediate coupling

Abstract A statistical method to simulate detailed line accounting (DLA) calculations of complex spectra is proposed. The method is based on the recently developed partially resolved transition array model. Numerical examples show that spectrum calculations using the statistical approach are in good agreement with DLA results. In particular, the statistical method conserves systematic line coincidences across transition arrays differing only in the subshell occupation of excited spectator electrons important in opacity calculations. In addition, it is computationally efficient; hence, it can accelerate spectrum calculations without introducing significant uncertainties whenever the DLA method is considered impractical.
Tunnel lens design study

A single optical component, a square prism with a spherical end cap, has been proposed for generating multipie real images of a single object. Ray-tracing computations show that a miniature tunnel lens of this type can multiplex coherent fiber optic arrays and perform digital optical computing operations with high efficiency and no crosstalk.
Use of a latitudinal gradient in bald cypress (Taxodium distichum) production to examine physiological controls of biotic boundaries and potential responses to environmental change

Aim Predictions of vegetation change with global warming require models that accurately reflect physiological processes underlying growth limitations and species distributions. However, information about environmental controls on physiology and consequent effects on species boundaries and ecosystem functions such as production is limited, especially for forested wetlands that are potentially important carbon sinks. Location The bald cypress (Taxodium distichum) region of the south-eastern United States was studied to examine how production of an important forested wetland varies with latitude and temperature as well as local hydrology. Methods We used published data to analyse litter production across a latitudinal gradient from 26.2 to 37.8° N to determine how bald cypress swamps might respond to alternate climate conditions and what changes might occur throughout the distributional range. Results Litterfall rates followed a bell shaped curve, indicating that production was more limited at the distributional boundaries (c. 225 g/m2 year−1) compared to the mid-range (795–1126 g/m2 year−1). This pattern suggests that conditions are suboptimal near both boundaries and that the absence of populations outside this latitudinal range may be largely due to physiological constraints on the carbon balance of dominant species. While dispersal limitations cannot be totally discounted, competition with other wetland types at the extremes of the range does not seem likely to be important because the relative basal area of bald cypress does not decrease near the edges of the range. Impaired hydrology depressed production across the entire range, but more in the south than the north. Main conclusions Our findings suggest that (1) physiological limitations constrain biotic boundaries of bald cypress swamps; (2) future changes in global temperature would affect litter production in a nonlinear manner across the distributional range; (3) local changes in hydrology may interact with climate to further reduce litter production, particularly at lower latitudes; and (4) southernmost forests could be extirpated if environmental conditions compromise carbon balance and water-use efficiency of trees.
Searching for an Environmental Kuznets Curve in China's air pollution

Abstract Intuitively, the concept of an Environmental Kuznets Curve (EKC) is relatively easy to understand: pollution will initially increase with economic development but then decrease again as incomes attain a certain level. The overall concept of pollution, however, actually consists of various components which may behave differently and are not easily combined into a single measure. As a result, the measurement or tracking of an EKC becomes more difficult as one tries to develop a tractable measure of pollution for modeling or policy purposes. For example, in China levels of sulfur dioxide and particulate pollution show some signs of diminishing while nitrogen dioxide levels have increased as China's auto fleet has grown. Consequently, different studies estimating an EKC often generate different results depending upon which pollutant is used and how it is measured. This paper generates composite measures of Chinese air pollution using Nemerow methodology as well as a new epidemiological index based upon the health effects of the pollutants. The paper then tests these index measures to determine whether they display evidence of an EKC and also to examine how they behave in comparison to the individual pollutants.
Karst hydrology of Grand Canyon, Arizona, USA.

Summary Caves in Grand Canyon, Arizona, USA fall into two main categories: those formed under unconfined conditions and those formed under confined conditions. This study focuses on the hydrology and paleohydrology of the confined caves in the Redwall–Muav aquifer, where the aquifer is overlain by rocks of the Supai Group and underlain by the Bright Angel Shale. Unconfined caves are discussed only in their relation to confined caves. Discharge for confined groundwater was, as it is today, primarily from the Redwall Limestone where it has been incised by the main canyon or its tributaries and where it has converged along a structural low or fault. Descent of the potentiometric surface (or water table) over time is recorded by one ore episode and six cave episodes: (1) emplacement of Cu–U ore, (2) precipitation of iron oxide in cavities, (3) dissolution of cave passages, (4) precipitation of calcite-spar linings over cave passage walls, (5) precipitation of cave mammillary coatings, (6) minor replacement of cave wall and ceiling limestone by gypsum, and (7) deposition of subaerial speleothems. The mammillary episode records the approximate position of the water table when the incision of the canyon was at that level. Discharge toward spring points has reorganized and adjusted with respect to ongoing canyon and side-canyon incision. The dissolution of Grand Canyon confined caves was the result of the mixing of epigene waters with hypogene waters so that undersaturation with respect to calcite was achieved. The karst hydrology of Grand Canyon may be unique compared to other hypogene cave areas of the world.
Globally convergent conjugate gradient algorithms

The paper examines a method of implementing an angle test for determining when to restart conjugate gradient methods in a steepest descent direction. The test is based on guaranteeing that the cosine of the angle between the search direction and the negative gradient is within a constant multiple of the cosine of the angle between the Fletcher-Reeves search direction and the negative gradient. This guarantees convergence, for the Fletcher-Reeves method is known to converge. Numerical results indicate little, if anything, is lost in efficiency, and indicate gains may well be possible for large problems.
An experimental application of a social reinforcement approach to the problem of job-finding.

Abstract The current conception of the employment process is that positions become available, are publicized, and are filled by the most qualified job seekers. An alternative conception is proposed that social factors play a major role in the process and that job finding can be analyzed as an exchange of social reinforcers in which the first behavioral step is to locate job openings. A questionnaire survey of 120 jobs found that two-thirds of the job leads came from friends or relatives who: (1) usually knew of a specific opening (63%); (2) were themselves employed by the hiring firm (71%); and (3) actively influenced the hiring process (53%). An experimental evaluation was made of an “Information-Reward” advertisement procedure for motivating community residents to report unpublicized openings. It was found that the Information-Reward procedure produced 10 times as many job leads and eight times as many placements as a noreward control advertisement. These findings represent a first step toward a much needed technology of job finding that is based on experimental evidence and support the notion that the employment process depends on factors unrelated to work skills.
THE LAST MILE: AN EXAMINATION OF EFFECTS OF ONLINE RETAIL DELIVERY STRATEGIES ON CONSUMERS

The Internet has increased the level of importance of the end-consumer market to transportation carriers. In two between subject experiments, carrier disclosure on retail merchant websites is examined as a strategic differentiation strategy. Predictions are offered concerning effects of carrier disclosure strategies on product delivery-related expectations, consumer attitudes, and intentions to purchase a product online. Results from Study 1 reveal significant differences between disclosure and nondisclosure of the carrier for numerous product delivery-related variables, as well as many differences between the six carriers examined in this first study. Study 2 extends these findings by showing that providing consumers with a choice of carrier leads to increased levels of satisfaction with the online experience and greater willingness to buy, relative to nondisclosure and disclosure strategies.
A simplification of a conversation design scheme using Petri nets

In the conversation design procedure, the definition of the state of the system is one of the most important aspects. The question is how to identify transitions in Occam programs in order to express them as Petri nets. In the paper, a simplified transition identification method is proposed. Using the robot arm control program of A.M. Tyrrell and D.J. Holding it is shown that the correspondent Petri net graph is simpler than theirs, but the communication state change table is the same. It is also shown that these two methods are equivalent. >
Radiation damage in non-fissile metallic alloys☆

Abstract A general survey is presented of radiation-induced displacement damage in non-fissile metallic alloys. The importance of the spatial arrangement of the vacancies and interstitials so produced is highlighted, especially as a guide to formulating an appropriate gauge for the various radiation-induced phenomena considered—i.e. hardening, embrittlement, growth, creep, swelling and fracture. The present level of theoretical understanding and the technological import of these phenomena are also assessed.
Progress in atherosclerotic plaque imaging

Cardiovascular diseases are the primary cause of mortality in the industrialized world, and arterial obstruction, triggered by rupture-prone atherosclerotic plaques, lead to myocardial infarction and cerebral stroke. Vulnerable plaques do not necessarily occur with flow-limiting stenosis, thus conventional luminographic assessment of the pathology fails to identify unstable lesions. In this review we discuss the currently available imaging modalities used to investigate morphological features and biological characteristics of the atherosclerotic plaque. The different imaging modalities such as ultrasound, magnetic resonance imaging, computed tomography, nuclear imaging and their intravascular applications are illustrated, highlighting their specific diagnostic potential. Clinically available and upcoming methodologies are also reviewed along with the related challenges in their clinical translation, concerning the specific invasiveness, accuracy and cost-effectiveness of these methods.
How To Define Neighborhood

(1972). How To Define Neighborhood. The Professional Geographer: Vol. 24, No. 3, pp. 227-228.
Examining power grid's capacity to meet transportation electrification demand

Plug-in hybrid electric vehicles (PHEVs) are the most promising approach to reducing petroleum use. The penetration of PHEVs is not yet significant; however, they raised a question of whether the existing power system can handle the extra load. Uncertainty arising from various factors such as charging-start time, vehicle type, miles driven, and the existing power grid load profile have motivated researchers to evaluate the impact of PHEVs using probabilistic approaches. The present study develops a model for examining the existing power system capacity to meet the PHEV load demand. The analysis considers PHEV charging as a stochastic event, and it is carried out in a discrete event simulation environment. As case studies, the model is applied to two different regions in the United States.
Review of the geosecs project

Abstract The Geochemical Ocean Sections Study (GEOSECS) provided the first comprehensive data set for the distribution of chemical species in the world ocean. For the first time chemists who measured nutrients, radiosotopes, stable isotopes, carbon, gases, trace metals, and particles were on the same ship working on the same or almost the same samples. They were supported by high quality hydrographic data available soon after each leg was completed. There were numerous intercomparison studies involving different laboratories which helped to sort out many analytical problems. But the data themselves provided an even more valuable criteria as the principle of oceanographic consistency began to be appreciated. This principle states that chemical data from the ocean generally follow relatively simple patterns illustrated by profiles of salinity, temeerature, nutrients, oxygen or other tracers which have been measured reliably. Even if several laboratories produced similar data sets of widely scattered concentrations of a trace metal, the data would be suspect unless some reason could be found for the scatter. This principle is still not widely appreciated by chemists studying other natural waters. Only four isotopes were routinely measured on GEOSECS by alpha spectrometry: 228Ra, 228Th, 210Pb, and 210Po (the two beta-active isotopes were measured by extracting their alpha-active daughters). The criteria for assessing the results were based on laboratory intercomparisons and on the oceanographic consistency of the data. Other low level radioisotope measurements include 14C, 222Rn, 137Cs, 90Sr, and 32Si. With the exception of 222Rn which was measured by alpha scintillation counting aboard the ship, the analyses were made by beta or gamma techniques in shore laboratories.
Ultrastructural studies of human prostatic neoplasia.

Forty-two specimens of human prostatic neoplasia (32 carcinomas, eight benign hyperplasia, two bladder tumors infiltrating prostatic tissue, and 15 tissue cultures derived from prostatic neoplasia) were examined by electron microscopy. Intracisternal viruslike particles, 150-200 nm in diameter and budding, were found in epithelial cells of four carcinomas. In some of these particles, an electron-dense central core or two concentric layers were discernible. In addition, particles resembling type C virus particles, 90-130 nm in diameter, were observed in intracytoplasmic vacuoles in five cases of carcinomas and in one case of benign prostate hyperplasia. Thus, viruslike particles were found in 9 of 32 cases of prostate carcinoma and in one of eight cases of benign prostate hyperplasia. Virus particles have, so far, not been found in any of the tissue culture specimens. Further studies are required to determine the nature of these particles and their relationship to the origin of human prostatic neoplasia. Additional observations in both benign hyperplasia and carcinoma include intranuclear mitochondria, multilayered nuclear inclusions, bundles of intranuclear fibrils, intracytoplasmic tubules, extracellular tubulo-filamentous structures, and cilia.ltilayered nuclear inclusions, bundles of ilo-filamentous structures, and cilia.
‘It's important to know when to turn back‘ — An interview with Albert Lowenfels

Dr. Albert Lowenfels made outstanding contributions to the understanding of pancreatic diseases. His exceptional achievements in the field of pancreatic epidemiology were seminal for the characterization of lifestyle factors such as smoking, drinking and obesity in the pathogenesis of pancreatic diseases. In this interview, Dr. Lowenfels shares with Pancreatology his experience as pancreatic researcher.