bluuebunny/crossref_metadata_2025 huggingface dataset:
The augmented predictive analyzer for context-free languages—its relative efficiency
Authors: Kuno Susumu
Published: July 2002

It has been proven by Greibach that for a given context-free grammar G, a standard-form grammar G

s

, can be constructed, which generates the same language as is generated by G and whose rules are all of the form
Z
→
cY
1
···

Y
m

(
m
≥ 0) where
Z
and

Y
i

are intermediate symbols and
c
a terminal symbol. Since the predictive analyzer at Harvard uses a standard-form grammar, it can accept the language of any context-free Grammar
G
, given an equivalent standard-form grammar

G
s

. The structural descriptions
SD
(

G
s
, χ

) assigned to a given sentence χ by the predictive analyzer, however, are usually different from the structural descriptions
SD
(
G, χ
) assigned to the same sentence by the original context-free grammar
G
from which

G
s

is derived.

In Section 1, an algorithm, originally due to Abbott is described, which converts a given context-free grammar into an
augmented
standard-form grammar each of whose rules is in standard form, supplemented by additional information describing its derivation from the original context-free grammar. A technique for performing the
SD
(

G
s
, χ

) to
SD
(
G, χ
) transformation effectively is also described.

In Section 2, the augmented predictive analyzer as a parsing algorithm for arbitrary context-free languages is compared with two other parsing algorithms: a selective top-to-bottom algorithm similar to Irons' “error correcting parse algorithm” and
CORC—the Cornell computing language
Authors: Conway R. W. , Maxwell W. L.
Published: July 2002

CORC is an experimental computing language that was developed at Cornell University to serve the needs of a large and increasing group of computer users whose demands are both limited and intermittent. These are the laymen of the computing world, who chose to become as little concerned as possible in the computing process and mechanics, but who would like to benefit from the computational ability that is now commonplace. At a university most of the faculty and student users would fall into this category. In recognition of the current significance of the computer in every area of business, science and engineering there is increasing faculty interest in introducing some use of modern computation into the students' academic experience if this can be done without placing too great a burden on an already hard-pressed curriculum. But computing is not going to be widely used in mathematics and engineering courses if the mechanics of its use are a burden to either the teacher or the student, or if the time necessary to prepare, test and operate programs cuts significantly into the subject matter for which the course was intended. Some participation on the part of the student appears to be an academic virtue, as well as a practical economic necessity—we have never heard any university computing center expansionist, in his wildest moments, propose a completely closed shop programming-operating service for general undergraduate use. In their own research many of the faculty are in the same position as their students. They will use the computer if it is convenient to do so and if it does not involve a major diversion into a technical field which is essentially extraneous to the basic subject matter. The closed-shop computing service in which the professor has (in principle anyway) only to describe his problem to a professional is of course intended to serve this need but we believe it is axiomatic that no university computing center will ever be adequately staffed to
Length of strings for a merge sort
Authors: Knuth Donald E.
Published: July 2002

Detailed statistics are given on the length of maximal sorted strings which result from the first (internal sort) phase of a merge sort onto tapes. It is shown that the strings produced by an alternating method (i.e. one which produces ascending and descending strings alternately) tend to be only three-fourths as long as those in a method which produces only ascending strings, contrary to statements which have appeared previously in the literature. A slight modification of the read-backward polyphase merge algorithm is therefore suggested.
On the complexity of branching programs and decision trees for clique functions
Authors: Wegener Ingo
Published: July 2002

Exponential lower bounds on the complexity of computing the clique functions in the Boolean decision-tree model are proved. For one-time-only branching programs, large polynomial lower bounds are proved for
k
-clique functions if
k
is fixed, and exponential lower bounds if
k
increases with
n
. Finally, the hierarchy of the classes BP

d

(
P
) of all sequences of Boolean functions that may be computed by
d
-times only branching programs of polynomial size is introduced. It is shown constructively that BP
1
(
P
) is a proper subset of BP
2
(
P
).
Understanding the IS-user divide in IT innovation
Authors: Kettinger William J. , Lee Choong C.
Published: July 2002

To resolve turf wars and speed implementation, the traditional IS function and increasingly self-reliant end users need to spell out one another's responsibilities while focusing on common organizational benefits.
ACM's computing professionals face new challenges
Authors: Shneiderman Ben
Published: July 2002

Technologists can make a difference on so many critical fronts.
A generator of direct manipulation office systems
Authors: Hudson Scott E. , King Roger
Published: July 2002

A system for generating direct manipulation office systems is described. In these systems, the user directly manipulates graphical representations of office entities instead of dealing with these entities abstractly through a command language or menu system. These systems employ a new semantic data model to describe office entities. New techniques based on attribute grammars and incremental attribute evaluation are used to implement this data model in an efficient manner. In addition, the system provides a means of generating sophisticated graphics-based user interfaces that are integrated with the underlying semantic model. Finally, the generated systems contain a general user reversal and recovery (or undo) mechanism that allows them to be much more tolerant of human errors.
Curvature continuity and offsets for piecewise conics
Authors: Farin G.
Published: July 2002

In this paper the construction of curvature continuous, planar curves (open or closed) that consist of conic segments, represented in the rational Bézier form, is discussed, and an iterative procedure to compute their offset curves is outlined.
The 1986-1987 Taulbee survey
Authors: Gries D. , Marsh D.
Published: July 2002

The Computing Research Board's 1986-87 Taulbee Survey includes the latest statistics on production and employment of Ph.D.'s and faculty in computer science and engineering. For the first time, departments offering Ph.D.'s in computer engineering are also included.
Application of splay trees to data compression
Authors: Jones D. W.
Published: July 2002

The splay-prefix algorithm is one of the simplest and fastest adaptive data compression algorithms based on the use of a prefix code. The data structures used in the splay-prefix algorithm can also be applied to arithmetic data compression. Applications of these algorithms to encryption and image processing are suggested.
STRATEGIES FOR ATTENUATING PROTEIN-CATABOLIC RESPONSES IN THE CRITICALLY ILL
Authors: Ziegler, M.D Thomas R. , Gatzen, FRCS Christopher , Wilmore, M.D Douglas W.
Published: July 2002

▪ Abstract  Specialized enteral and parenteral nutrition are now a standard components of care in critically ill patients. This adjunctive therapy corrects and prevents nutrient deficiencies, attenuates the loss of body protein, and improves clinical outcomes in malnourished patients. Several novel strategies designed to improve the metabolic and clinical effects of specialized nutrition are under vigorous clinical investigation.

These new approaches include increased emphasis on enteral feeding to maintain intestinal absorptive, immune, and barrier function; administration of conditionally essential amino acids (glutamine, arginine); use of specialized lipid products and antiox idants; and administration of growth factors such as human growth hormone. Randomized, controlled clinical trials will define the clinical and metabolic efficacy and cost-effectiveness of these therapies in specialized nutrition support.
BETA-ADRENERGIC BLOCKING AGENTS IN THE TREATMENT OF CONGESTIVE HEART FAILURE: Mechanisms and Clinical Results
Authors: Doughty, MB MRCP FRACP Robert Neil , Sharpe, MD FRACP FACC Norman
Published: July 2002

▪ Abstract  Congestive heart failure is a major public health problem in Western countries. Despite current treatment including angiotensin converting enzyme inhibitors, mortality and morbidity remain high. The sympathetic nervous system is markedly activated in heart failure, and inhibition of this system with the beta-adrenergic blocking agents may provide further benefit. Several clinical trials involving over 3000 patients have shown that beta-blocker therapy improves left ventricular function in patients with heart failure. However, the effects of such therapy on symptoms and exercise tolerance have been variable. Recent reports have suggested that survival is improved with the beta-blocker carvedilol. Large-scale, long-term clinical trials are required to confirm these findings and to clearly define the role of this promising therapy for patients with heart failure.
Intestinal Pseudo-Obstruction
Authors: Coulie, MD, PhD Bernard , Camilleri, MD Michael
Published: July 2002

Pseudo-obstruction syndromes are increasingly recognized in clinical practice. They result from impairment of intrinsic neuromuscular or extrinsic control of gut motility. Typically, pseudo-obstruction syndromes result in features suggestive of mechanical obstruction and bowel dilatation in the absence of any demonstrable obstruction or mucosal disease. The syndrome may affect any region of the gut. Less severe variants without bowel dilatation are diagnosed by measurement of gastrointestinal transit and pressure profiles. The aims of treatment are restoration of nutrition and hydration, symptom relief, normalization of intestinal propulsion with prokinetics, and suppression of bacterial overgrowth. Surgery plays a limited role, adjunctive to medical treatment, facilitating enteral nutrition and decompression by means of jejunostomy. Infrequently, resection of localized disease or intestinal transplantation are indicated. The roles of intestinal pacemakers (interstitial cells of Cajal) and genetic mutations in the etiology of pseudo-obstruction, as well as the cost-benefit ratio of transplantation for pseudo-obstruction, will be clarified in the future.
Dietary Regulation of Intestinal Gene Expression
Authors: Sanderson I. R. , Naik S.
Published: July 2002

We are becoming increasingly aware of inherited genetic abnormalities as causes of disease. However, alterations in gene expression can also contribute to other disease processes. Recently it has been suggested that our environment may alter such genes and thus be a direct influence on disease. Diet is a potent mechanism for altering the environment of cells of most organs, particularly the gastrointestinal tract. This review addresses the influence of nutritional factors on intestinal gene regulation. These influences include insulin, which is not a dietary component but responds to dietary changes, and butyrate, a short chain fatty acid produced by normal intestinal flora. Manipulation of diet may be a means of treating intestinal disorders. Nutritional treatment therefore is also discussed in the light of its effect on gene expression.
DESENSITIZATION OF G-PROTEIN–COUPLED RECEPTORS IN THE CARDIOVASCULAR SYSTEM
Authors: Bünemann M. , Lee K. B. , Pals-Rylaarsdam R. , Roseberry A. G. , Hosey M. M.
Published: July 2002

▪ Abstract  Multiple mechanisms exist to control the signaling and density of G-protein-coupled receptors (GPRs). Upon agonist binding and receptor activation, a series of reactions participate in the turn off or desensitization of GPRs. Many GPRs are phosphorylated by protein kinases and consequently uncoupled from G proteins. In addition, many GPRs are sequestered from the cell surface and become inaccessible to their activating ligands. Both receptor:G protein uncoupling and receptor sequestration may involve the participation of arrestins or other proteins. A model for receptor regulation has been developed from studies of the β-adrenergic receptor. However, recent studies suggest that other GPRs important in the cardiovascular system, such as the muscarinic cholinergic receptors that regulate heart rate, might be regulated by mechanisms other than those that regulate the β-adrenergic receptors. This review summarizes our current understanding of the processes involved in the desensitization of GPRs.
Hypoxia-Induced Anapyrexia: Implications and Putative Mediators
Authors: Steiner Alexandre A. , Branco Luiz G. S.
Published: July 2002

▪ Abstract  Hypoxia elicits an array of compensatory responses in animals ranging from protozoa to mammals. Central among these responses is anapyrexia, the regulated decrease of body temperature. The importance of anapyrexia lies in the fact that it reduces oxygen consumption, increases the affinity of hemoglobin for oxygen, and blunts the energetically costly responses to hypoxia. The mechanisms of anapyrexia are of intense interest to physiologists. Several substances, among them lactate, adenosine, opioids, and nitric oxide, have been suggested as putative mediators of anapyrexia, and most appear to act in the central nervous system. Moreover, there is evidence that the drop in body temperature in response to hypoxia, unlike the ventilatory response to hypoxia, does not depend on the activation of peripheral chemoreceptors. The current knowledge of the mechanisms of hypoxia-induced anapyrexia are reviewed.
Antiangiogenic Effect of Angiotensin II Type 2 Receptor in Ischemia-Induced Angiogenesis in Mice Hindlimb
Authors: Silvestre Jean-Sébastien , Tamarat Radia , Senbonmatsu Takaaki , Icchiki Toshihiro , Ebrahimian Teni , Iglarz Marc , Besnard Sandrine , Duriez Micheline , Inagami Tadashi , Lévy Bernard I.
Published: July 2002

Abstract
—

This study examined the potential role of angiotensin type 2 (AT
2
) receptor on angiogenesis in a model of surgically induced hindlimb ischemia. Ischemia was produced by femoral artery ligature in both wild-type and AT
2
gene–deleted mice (
Agtr2
−
/Y). After 28 days, angiogenesis was quantitated by microangiography, capillary density measurement, and laser Doppler perfusion imaging. Protein levels of vascular endothelial growth factor (VEGF), endothelial nitric oxide synthase (eNOS), Bax, and Bcl-2 were determined by Western blot analysis in hindlimbs. The AT
2
mRNA level (assessed by semiquantitative RT-PCR) was increased in the ischemic hindlimb of wild-type mice. Angiographic vessel density and laser Doppler perfusion data showed significant improvement in ischemic/nonischemic leg ratio, 1.9- and 1.7-fold, respectively, in
Agtr2
−
/Y mice compared with controls. In ischemic leg of
Agtr2
−
/Y mice, revascularization was associated with an increase in the antiapoptotic protein content, Bcl-2 (211% of basal), and a decrease (60% of basal) in the number of cell death, determined by TUNEL method. Angiotensin II treatment (0.3 mg/kg per day) raised angiogenic score, blood perfusion, and both VEGF and eNOS protein content in ischemic leg of wild-type control but did not modulate the enhanced angiogenic response observed in untreated
Agtr2
−
/Y mice. Finally, immunohistochemistry analysis revealed that VEGF was mainly localized to myocyte, whereas eNOS-positive staining was mainly observed in the capillary of ischemic leg of both wild-type and AT
2
-deficient mice. This study demonstrates for the first time that the AT
2
receptor subtype may negatively modulate ischemia-induced angiogenesis through an activation of the apoptotic process.
Generalization and Selection of Examples in Feedforward Neural Networks
Authors: Franco Leonardo , Cannas Sergio A.
Published: July 2002

In this work, we study how the selection of examples affects the learning procedure in a boolean neural network and its relationship with the complexity of the function under study and its architecture. We analyze the generalization capacity for different target functions with particular architectures through an analytical calculation of the minimum number of examples needed to obtain full generalization (i.e., zero generalization error). The analysis of the training sets associated with such parameter leads us to propose a general architecture-independent criterion for selection of training examples. The criterion was checked through numerical simulations for various particular target functions with particular architectures, as well as for random target functions in a nonoverlapping receptive field perceptron. In all cases, the selection sampling criterion lead to an improvement in the generalization capacity compared with a pure random sampling. We also show that for the parity problem, one of the most used problems for testing learning algorithms, only the use of the whole set of examples ensures global learning in a depth two architecture. We show that this difficulty can be overcome by considering a tree-structured network of depth 2 log2(N) – 1.
On a Fast, Compact Approximation of the Exponential Function
Authors: Cawley Gavin C.
Published: July 2002

Recently Schraudolph (1999) described an ingenious, fast, and compact approximation of the exponential function through manipulation of the components of a standard (IEEE-754 (IEEE, 1985)) floating-point representation. This brief note communicates a recoding of this procedure that overcomes some of the limitations of the original macro at little or no additional computational expense.
Complexity Pursuit: Separating Interesting Components from Time Series
Authors: Hyvärinen Aapo
Published: July 2002

A generalization of projection pursuit for time series, that is, signals with time structure, is introduced. The goal is to find projections of time series that have interesting structure, defined using criteria related to Kolmogoroff complexity or coding length. Interesting signals are those that can be coded with a short code length. We derive a simple approximation of coding length that takes into account both the nongaussianity and the autocorrelations of the time series. Also, we derive a simple algorithm for its approximative optimization. The resulting method is closely related to blind separation of nongaussian, time-dependent source signals.
Orthogonal Series Density Estimation and the Kernel Eigenvalue Problem
Authors: Girolami Mark
Published: July 2002

Kernel principal component analysis has been introduced as a method of extracting a set of orthonormal nonlinear features from multivariate data, and many impressive applications are being reported within the literature. This article presents the view that the eigenvalue decomposition of a kernel matrix can also provide the discrete expansion coefficients required for a nonparametric orthogonal series density estimator. In addition to providing novel insights into nonparametric density estimation, this article provides an intuitively appealing interpretation for the nonlinear features extracted from data using kernel principal component analysis.
Reading Neuronal Synchrony with Depressing Synapses
Authors: Senn W. , Segev I. , Tsodyks M.
Published: July 2002

A recent experiment showed that neurons in the primary auditory cortex of the monkey do not change their mean firing rate during an ongoing tone stimulus. The only change was an enhanced correlation among the individual spike trains during the tone. We show that there is an easy way to extract this coherence information in the cortical cell population by projecting the spike trains through depressing synapses onto a postsynaptic neuron.
How to Design a Connectionist Holistic Parser
Authors: Ho Edward Kei Shin , Chan Lai Wan
Published: July 2002

Connectionist holistic parsing offers a viable and attractive alternative to traditional algorithmic parsers. With exposure to a limited subset of grammatical sentences and their corresponding parse trees only, a holistic parser is capable of learning inductively the grammatical regularity underlying the training examples that affects the parsing process. In the past, various connectionist parsers have been proposed. Each approach had its own unique characteristics, and yet some techniques were shared in common. In this article, various dimensions underlying the design of a holistic parser are explored, including the methods to encode sentences and parse trees, whether a sentence and its corresponding parse tree share the same representation, the use of confluent inference, and the inclusion of phrases in the training set. Different combinations of these design factors give rise to different holistic parsers. In succeeding discussions, we scrutinize these design techniques and compare the performances of a few parsers on language parsing, including the confluent preorder parser, the backpropagation parsing network, the XERIC parser of Berg (1992), the modular connectionist parser of Sharkey and Sharkey (1992), Reilly's (1992) model, and their derivatives. Experiments are performed to evaluate their generalization capability and robustness. The results reveal a number of issues essential for building an effective holistic parser.
Full Mode and Attribution Mode in Environmental Analysis
Authors: de Haes Helias Udo , Heijungs Reinout , Huppes Gjalt , van der Voet Ester , Hettelingh Jean‐Paul
Published: July 2002

Several tools exist for the analysis of the environmental impacts of chains or networks of processes. These relatively simple tools include materials flow accounting (MFA), substance flow analysis (SFA), life‐cycle assessment (LCA), energy analysis, and environmentally extended input‐output analysis (IOA), all based on fixed input‐output relations. They are characterized by the nature of their flow objects, such as products, materials, energy, substances, or money flows, and by their spatial and temporal characteristics. These characteristics are insufficient for their methodological characterization, and sometimes lead to inappropriate use. More clarity is desirable, both for clearer guidance of applications and for a more consistent methodology development. In addition to the nature of the flow object and to spatial and temporal characteristics, another key feature concerns the way in which processes are included in a system to be analyzed.

The inclusion of processes can be done in two fundamentally different ways: according to a full mode of analysis, with the inclusion of all flows and related processes to their full extent as present in a region in a specific period of time; and according to an attribution mode, taking processes into account insofar as these are required for a given social demand, function, or activity, in principle whenever and wherever these processes take place. This distinction, which cuts across families of tools that traditionally belong together, appears to have significant methodological and practical implications. Thus the distinction between the two modes of analysis, however crucial it may be, strengthens the idea of one coherent family of tools for environmental systems analysis.
A NOTE ON THE RISE OF SURAT IN THE SIXTEENTH CENTURY
Authors: Subrahmanyam Sanjay
Published: July 2002

Far less attention has been paid to the rise to importance of the Gujarati port of Surat, than to its decline. This brief essay, a tribute to the memory of Surat's best-known historian, Ashin Das Gupta, attempts to address the problem of its rise before the Mughal conquest of Gujarat in the 1570s. It argues that once Diu had been taken over by the Portuguese in 1535, Surat emerged as a crucial link between Southeast Asia and West Asia. Thus, one needs to look not only at the relationship between the port and its hinterland, but to Surat's role as an entrepôt, in order to explain its rise.
JOHN WESLEY SLEPT HERE: AMERICAN SHRINES AND AMERICAN METHODISTS
Authors: Tweed Thomas
Published: July 2002

Historians of religion have devoted little attention to shrines in the United States, and the limited scholarship that is available has overlooked Protestants. Protestants, most interpreters have assumed, do not have shrines or make pilgrimages. In this essay I define and classify shrines, surveying a wide range of sacred sites in the United States. Then I challenge the assumptions about Protestants and pilgrimage. Focusing on the United Methodists, I argue that while the spiritual descendants of John Wesley do not consecrate all types of sacred sites or endorse all pilgrimage practices, commemorative shrines play a role in American Methodist piety. If I am right, Protestants, and American Methodists in particular, are less anomalous in the history of religion than most scholars have assumed.
DER MOND UND DIE PLEJADEN GRIECHISCH-ORIENTALISCHE PARALLELEN
Authors: Müller Hans-Peter
Published: July 2002

In den letzten Jahren mehrte sich der Eindruck, dass die griechische und die altorientalische Kultur zueinander Berührungen aufweisen, die auch alttestamentliche Tatbestände zu erhellen vermögen. Die Erwähnung von Mond und Plejaden in dem bekannten aiolischen Gedicht "Sappho" 94 D. gibt u.a. Anlass, nach der Darstellung beider Himmelskörper in der palästinischen und babylonischen Glyptik zu fragen, altorientalischen, alttestamentlichen und griechischen Bezugnahmen auf die genannten Himmelskörper nachzugehen sowie mythische Erinnerungsreste aufzuweisen, die nicht nur an den Etymologien von jārēah "Mond", käsä" "Vollmond", lebānā "weiße Dame" (für den Mond) und kesîl "Orion", sondern auch an Texten wie Am. v 8; Hi. ix 8-10; xxxi 26; xxxviii 31; Hld. vi 10 und relevanten babylonischen Entsprechungen haften. Der Artikel schließt mit Bemerkungen zur lyrischen Reproduktion eines sonst nicht mehr lebendigen mythisch-religiösen Naturumgangs.
WHERE THE GOSPEL TEXT BEGINS: A NON-THEOLOGICAL INTERPRETATION OF MARK 1:1
Authors: Croy N. Clayton
Published: July 2002

Dionysius of Halicarnassus, rhetorician and historian in Rome during the waning years of the first century B.C.E., wrote an essay on Thucydides in which he noted that some critics faulted the great historian of the Peloponnesian War for the arrangement (ταξις) of his work. They complained that Thucydides "neither chose the beginning of the history that was needed, nor did he fit it with a suitable ending." These critics insisted that "by no means the least important part of good arrangement was to choose a beginning, prior to which there would be nothing, and to conclude the matter with an ending in which nothing seemed to be lacking" (On Thucydides 10). If we overlook for the moment that Thucydides's history differs significantly in literary terms from the Gospel of Mark, we might find it remarkable how the same criticism has been leveled against the author of the second gospel. The oddity of Mark's ending at 16:8 is well known, but the beginning of Mark is also inauspicious. Does he, like Thucydides, suffer from faulty ταξις? This paper will examine the beginning of Mark's gospel and propose, or in truth, recall and corroborate, a rather pedestrian explanation of its many peculiarities.
BEHAVIORAL ADAPTATIONS OF AN AFRICAN PONERINE ANT IN THE CAPTURE OF MILLIPEDES
Authors: Dejean  , Suzzoni  , Schatz
Published: July 2002

Workers of the ponerine ant Plectroctena minor are equipped with hypertrophied mandibles that can seize tubular millipedes, their essential prey, of up to 4 mm in diameter. We studied their predatory behavior in four situations where they captured spirostreptid millipedes. (1) P. minor workers generally seized millipedes of less than 4 mm in diameter dorsally and by their anterior part. During seizure the mandibles slipped on the exoskeletal coils of the millipede body and were caught between two segments that were slightly separated by the strong pressure. This facilitated stinging that mostly occurred ventrally in the soft intersegmentary space of the seized zone. (2) When a millipede was more than 4 mm in diameter, the workers seized it by an appendage before stinging or by wrapping themselves around the prey, then recruited nestmates in order to retrieve it. (3) The workers probably perceived kairomones from millipedes rolled into sloughing lodges as they opened the lodges and singly captured individuals less than 4 mm in diameter. Larger individuals (more than 4 mm in diameter) were captured after the workers recruited nestmates that generally cut up these prey on the spot. (4) When encountered in a test-tube simulating galleries, 95 to 105 mmlong millipedes (around 8 mm in diameter) were always captured. When the millipede's head was near the test-tube opening, the workers gripped the antennae or mandibles and stung the extreme anterior part of the millipede body, triggering rapid paralysis. In this case, they were even able to singly master then to retrieve these millipedes 94 to 117 times their weight, which represents the highest ratio for a solitary hunting strategy in ants. When the hind part of the millipede was near the test-tube opening, seizure was difficult and nestmates were recruited in most cases. We concluded that the behavioral flexibility of P.minor, which mainly occurred during the solitary phase of prey mastering, permitted the capture of millipedes of a wide range of sizes.
ON THE ORIGIN OF MISOPHRIOID COPEPODS FROM ANCHIALINE CAVES
Authors: Jaume Damia , Boxshall Geoff
Published: July 2002

Phylogenetic relationships between the known genera of the order Misophrioida permit the identification of two lineages: one consisting of the family Misophriidae Brady, 1878 which comprises seven genera, and a new, monotypic family, the Palpophriidae Boxshall & Jaume, 1999; the other consisting of another new family, the Speleophriidae Boxshall & Jaume, 1999, comprising eight genera. Habitat exploitation by these families is discussed: members of the Misophriidae are primarily hyperbenthic, those of the Palpophriidae and Speleophriidae are primarily cavernicolous in anchialine habitats. The occurrence of misophriids in littoral and submarine caves is interpreted as evidence of a relatively recent landward extension of the habitat range in this family, from a shallow-water hyperbenthic ancestor. The distribution of speleophriids in anchialine caves is interpreted as resulting from a colonization episode prior to the closure of the Tethys Sea. The analysis also indicates that deep-water forms may represent a secondary colonization rather than an indication of deep-water ancestry for the entire order. El estudio de las relaciones filogeneticas entre los distintos generos pertenecientes al orden Misophrioida ha permitido la identificacion de dos linajes principales: uno compuesto por la familia Misophriidae Brady, 1878, integrada por siete generos, y una familia nueva, Palpophriidae Boxshall & Jaume, 1999; el otro, integrado por otra nueva familia, Speleophriidae Boxshall & Jaume, 1999, compuesta por ocho generos. Se discute la explotacion que del habitat hacen estas familias: los Misophriidae son primariamente hiperbenticos, mientras que Palpophriidae y Speleophriidae son cavernicolas en medio anquialino. La presencia de misofriidos en cuevas litorales y submarinas es interpretado como evidencia de una relativamente reciente extension tierra adentro del habitat ordinario de esta familia, a partir de un ancestro hiperbentico propio de aguas someras. La distribucion de los espeleofriidos en cuevas anquialinas es interpretada como resultado de un episodio de colonizacion anterior a la oclusion del mar de Tetis. El analisis indica tambien que las formas de aguas profundas representan una colonizacion secundaria mas que indicacion de un ancestro de aguas profundas para el orden entero.
Alteration mineralogy of Cretaceous basalt from ODP Site 1001, Leg 165 (Caribbean Sea)
Authors: Clayton T. , Pearce R. B.
Published: July 2002

Secondary clay minerals observed in the two uppermost basalt lava flows at ODP Site 1001, in the Caribbean Sea, drilled from the large igneous province of Cretaceous age, result from low-temperature alteration processes. Alteration mainly proceeds by circulation and diffusion of sea water. Six different types of clay mineral assemblage were recognized. Initial alteration with oxygenated sea water involves Fe and K fixation, creating visible oxidation halos parallel to the sides of cracks and fissures. A saponite/ beidellite mixture, interstratified smectite-glauconite, interstratified glauconite-nontronite and Fe oxyhydroxides are obtained depending on the distance from fluid conduits. The presence of beidellite may be due to enhanced Al mobilization resulting from high fluid flux. These early minerals are cross-cut by thin veins of pure celadonite or glauconite with further vesicle infill. Late-stage alteration is typified by the formation of saponite and takes place under closed reducing conditions resulting from deposition of the sedimentary overburden.
Cation partitioning in an unusual strontian potassicrichterite from Siberia: Rietveld structure refinement and Mössbauer spectroscopy
Authors: Sokolova E. V. , Kabalov Yu. K. , McCammon C. , Schneider J. , Konev A. A.
Published: July 2002

The crystal structure of strontian potassicrichterite (Mg4.871Fe0.1263+ Mn0.052)Σ5.049(Na1.425Ca0.348Sr0.297)σ2.07K0.873Si8.048O22(OH)2.15 – an unusual amphibole containing up to 3.7 wt.% SrO from the Murun alkaline massif, Eastern Siberia has been refined from X-ray powder diffraction data in monoclinic space group C2/m, with a = 10.0325(1) Å, b = 17.977(1) Å, c = 5.2698(1) Å, and β = 104.70(1)°. According to Mössbauer spectroscopy, nearly all iron occurs as Fe3+ in octahedral coordination. Rietveld refinement shows the Fe3+ to be ordered onto the M(2) site. Sr is completely ordered onto M(4).
Crystal structure and revision of the chemical formula of georgiadesite, Pb4(AsO3)Cl4(OH)
Authors: Pasero M. , Vacchiano D.
Published: July 2002

The crystal structure of the rare secondary lead mineral georgiadesite has been solved from single-crystal X-ray diffraction data (R = 0.071). The structure can be visualized in terms of alternating puckered (100) layers of [Pbϕ6] octahedra and [Pbϕ8] bicapped trigonal prisms (ϕ = generic anion). Lead also occurs in irregular, lopsided polyhedra. This structural study shows unambiguously that arsenic occurs as As3+ and not as As5+. The chemical formula of georgiadesite has therefore been revised, on structural grounds, to Pb4(AsO3)Cl4(OH).
Phase transitions in silicate perovskites from first principles
Authors: Warren Michele C. , Ackland Graeme J. , Karki Bijaya B. , Clark Stewart J.
Published: July 2002

The equilibrium structures of cubic, tetragonal and orthorhombic phases of magnesium silicate perovskite are found from first principles electronic structure calculations. Zone centre and zone boundary phonons of each phase are also calculated from ab initio forces from finite displacments, and phase transitions between the phases are analysed in terms of phonon instabilities, and coupling between modes. Both the cubic and tetragonal phases have strongly unstable modes dominated by rotation of the SiO6 octahedra, which freeze in to ultimately form the orthorhombic phase. First priniciples molecular dynamics simulations at finite temperatures are used to further investigate the stability of the intermediate tetragonal phase and the coupling between participating phonon modes. The implications for a transition temperature between orthorhombic and tetragonal phases are discussed.
Treatment with NS3623, a novel Cl-conductance blocker, ameliorates erythrocyte dehydration in transgenic SAD mice: a possible new therapeutic approach for sickle cell disease
Authors: Bennekou Poul , de Franceschi Lucia , Pedersen Ove , Lian Lurong , Asakura Toshio , Evans Greg , Brugnara Carlo , Christophersen Palle
Published: July 2002

The dehydration of sickle red blood cells (RBCs) through the Ca-activated K channel depends on the parallel movement of Cl ions. To study whether Cl-conductance block might prevent dehydration of sickle RBCs, a novel Cl-conductance inhibitor (NS3623) was characterized in vitro using RBCs from healthy donors and sickle cell patients and in vivo using normal mice and a transgenic mouse model of sickle cell disease (SAD mice). In vitro, NS3623 reversibly blocked human RBC Cl-conductance (gCl) with an IC50 value of 210 nmol/L and a maximal block of 95%. In vivo, NS3623 inhibited RBC gCl after oral administration to normal mice (ED50 = 25 mg/kg). Although gCl, at a single dose of 100 mg/kg, was still 70% inhibited 5 hours after dosing, the inhibition disappeared after 24 hours. Repeated administration of 100 mg/kg twice a day for 10 days caused no adverse effects; therefore, this regimen was chosen as the highest dosing for the SAD mice. SAD mice were treated for 3 weeks with 2 daily administrations of 10, 35, and 100 mg/kg NS3623, respectively. The hematocrit increased, and the mean corpuscular hemoglobin concentration decreased in all groups with a concomitant increase in the intracellular cation content. A loss of the densest red cell population was observed in conjunction with a shift from a high proportion of sickled to well-hydrated discoid erythrocytes, with some echinocytes present at the highest dosage. These data indicate feasibility for the potential use of Cl-conductance blockers to treat human sickle cell disease.
A prospective randomized phase II trial of GM-CSF priming to prevent topotecan-induced neutropenia in chemotherapy-naive patients with malignant melanoma or renal cell carcinoma
Authors: Janik John E. , Miller Langdon L. , Korn Edward L. , Stevens Diane , Curti Brendan D. , Smith John W. , Sznol Mario , Conlon Kevin C. , Sharfman William , Urba Walter J. , Gause Barry L. , Longo Dan L.
Published: July 2002

We conducted a phase II randomized trial of recombinant granculocyte-macrophage colony-stimulating factor (GM-CSF) administered before topotecan chemotherapy to determine whether it could prevent myelosuppression and to determine the antitumor activity of this topoisomerase I inhibitor in 53 patients with metastatic malignant melanoma and renal cell cancer. All patients received GM-CSF after topotecan at a dose of 250 μg/m2 daily for at least 8 days. Patients randomly assigned to receive GM-CSF priming were treated with GM-CSF at 250 μg/m2 twice daily for 5 days before treatment. Twenty-five patients were randomly assigned to receive GM-CSF priming and 28 to receive topotecan without priming. The primary analysis was restricted to the protective effects seen during the first cycle of therapy. Grade 4 neutropenia occurred in 8 of 23 patients (35%) and grade 3 neutropenia in 5 of 23 patients (22%) randomized to GM-CSF priming, whereas 18 of 26 (69%) and 5 of 26 (19%) patients experienced grade 4 or 3 neutropenia, respectively, without GM-CSF priming (P = .0074). The mean duration of neutropenia was reduced by GM-CSF priming: grade 3 neutropenia from 5.2 ± 0.7 to 2.8 ± 0.7 days (P = .0232) and grade 4 neutropenia from 2.7 ± 0.6 to 1.1 ± 0.4 days (P = 0.0332). The protective effects of GM-CSF extended to the second cycle of treatment. The incidence of febrile neutropenia was also reduced. Chemotherapy-induced anemia and thrombocytopenia were similar in both groups. One partial response was seen in a patient with melanoma, and one patient with renal cell cancer had complete regression of pulmonary metastases and was rendered disease-free by nephrectomy.
A novel δβ fusion gene expresses hemoglobin A (HbA) not Hb Lepore: Senegalese δ0β+thalassemia
Authors: Zertal-Zidani Samia , Ducrocq Rolande , Weil-Olivier Catherine , Elion Jacques , Krishnamoorthy Rajagopal
Published: July 2002

This study identified and characterized a novel δβ fusion gene in which the δ-globin gene promoter is linked to intact β-globin coding sequences in a Senegalese family. It results from a 7.4-kb deletion that removes the δ-globin coding sequences, the δβ intergenic region as well as the β-globin gene promoter and causes δ0β+ thalassemia with hemoglobin A expressed at the 11% to 15% range. The phenotype of this naturally occurring δβ hybrid gene not only clarifies, in an in vivo context, the respective strength of δ- and β-globin gene promoters, but also emphasizes the importance of β-globin intragenic sequences in the expression of β-globin chains.
Combined blockade of GPX4 and activated EGFR/HER3 bypass pathways inhibits the development of ALK‐inhibitor‐induced tolerant persister cells in ALK‐fusion‐positive lung cancer
Authors: Furugaki Koh , Fujimura Takaaki , Sakaguchi Narumi , Watanabe Yasutaka , Uchibori Ken , Miyauchi Eisaku , Hayashi Hidetoshi , Katayama Ryohei , Yoshiura Shigeki
Published: October 2024

Cancers can develop resistance to treatment with ALK tyrosine kinase inhibitors (ALK‐TKIs) via emergence of a subpopulation of drug‐tolerant persister (DTP) cells that can survive initial drug treatment long enough to acquire genetic aberrations. DTP cells are thus a potential therapeutic target. We generated alectinib‐induced DTP cells from a patient‐derived ALK+ non‐small‐cell lung cancer (NSCLC) cell line and screened 3114 agents in the anticancer compounds library (TargetMol). We identified phospholipid hydroperoxide glutathione peroxidase GPX4 as being involved in promoting the survival of DTP cells. GPX4 was found to be upregulated in DTP cells and to promote cell survival by suppressing reactive oxygen species (ROS) accumulation; GPX4 inhibitors blocked this upregulation and facilitated ROS‐mediated cell death. Activated bypass signals involving epidermal growth factor receptor (EGFR)/receptor tyrosine‐protein kinase erbB‐3 (HER3) were also identified in DTP cells, and co‐treatment with EGFR‐TKI plus ALK‐TKI enhanced ROS levels. Triple combination with an ALK‐TKI plus a bypass pathway inhibitor plus a GPX4 inhibitor suppressed cell growth and induced intracellular ROS accumulation more greatly than did treatment with each agent alone. The combined inhibition of ALK plus inhibition of activated bypass signals plus inhibition of GPX4 may be a potent therapeutic strategy for patients with ALK+ NSCLC to prevent the development of resistance to ALK‐TKIs and lead to tumor eradication.
Grain Size‐Dependent Thermoelectric Performances of Al2O3 Addition into BiSbTe Alloy During Heat Treatment Fabricated by Mechanical Alloying
Authors: Ha Ji‐Won , Rathinam Vasudevan , Go Eun‐Ha , Hong Soon‐Jik
Published: October 2024

Herein, the effect of grain size and its texture orientations on the microstructural and thermoelectric performances of Al2O3 nanofiber (6 wt%)‐doped p‐type BiSbTe (BST)/Al2O3(N) composite before and after heat treatment is revealed. The results are also compared with the spherical Al2O3 particle addition of BST/Al2O3(S) composite. BiSbTe powders are fabricated through water atomization and BST/Al2O3 composites using ball milling followed by spark plasma sintering to obtain bulk compaction. The grain sizes are in the submicrometer ranges for BST/Al2O3 composites; however, it is found to increase after heat treatment, implying that an increment of electrical conductivity for the heat‐treated BST/Al2O3(N) leads to the enhancement in the power factor of 2.1 mW m−1 K−2 at 375 K. On the other hand, the lattice thermal conductivity (κph) is significantly reduced to 0.52 W m−1 K−1 at 400 K and the corresponding thermal conductivity (κ) of 0.89 W m−1 K−1 is attributed to the effective phonon scattering via an interface between low‐dimensional nanofiber of Al2O3 and BST bulk. Also, highly textured grain orientations after heat treatment help to enhance phonon scattering despite larger grain size. Overall, a substantial enhancement of the figure of merit ZTmax. 0.95 at 400 K is compared to BST/Al2O3(S)_HT (=0.7).
Superplastic Deformation Behavior of 2 mm Ti60 Rolled Sheet in Air Environment
Authors: Dong Shulin , Qu Shiwen , Chen Zhiyong , Qu Yingdong , Chen Ruirun , Li Guanglong , Zhang Wei , Liu Shibing
Published: October 2024

The superplastic deformation behavior of 2 mm Ti60 sheet is studied, and the constitutive equation of superplastic deformation is established. The results show that when the strain rate is 5.00 × 10−3 s−1 and the temperature is 950 °C, the maximum superplastic elongation reaches 400%. Through the analysis of the true strain–true stress curve, it is found that the average apparent activation energy (Q) is 490.783 kJ mol−1 and the average strain rate sensitivity (m) is 0.49. Dynamic spheroidization (DG) promotes the transformation of lath α phase to equiaxed α phase. Dynamic recrystallization (DRX) promotes the generation of high‐angle grain boundaries (θ > 15°). After deformation, the strength of R‐type textures changes significantly. From the grip to the tip, the strength of R‐type texture gradually weakens, which is mainly caused by the rotation of grains during deformation. The deformation mechanism of Ti60 sheet is dominated by grain boundary sliding, and is coordinated by grain growth, DG, DRX, dislocation motion, and grain rotation.
In situ Mechanical Foaming of Hierarchical Porous MoC for Assembling Ultra‐light, Self‐cleaning, Heat‐insulation, Flame‐retardant, and Infrared‐stealth Device
Authors: Zhang Yanan , Tian Yuanyuan , Xu Nuo , Cui Peiyu , Guo Liyuan , Ma Jiacheng , Kang Yifan , Qin Long , Wu Fan , Zhang Lei , Huang Wenhuan
Published: October 2024

Molybdenum carbide (MoC) integrated into a carbon matrix, known for its robust interfacial polarization, emerges as a promising ultra‐lightweight EM wave absorber. However, the fabrication of such materials remains a formidable challenge. Herein, a facile and scalable strategy for preparing MoC‐incorporated carbon matrix employing ZnMo‐HZIF foam material through ball‐milling foaming and calcination process as a promising electromagnetic wave materials (EWAMs). In detail, the 3D foam structure reaches impedance matching, and heterogeneous interfaces of N‐doped MoC‐incorporated carbon material (MoC/NC) promote the dipolar/interfacial polarization, confirmed by the hologram. Mo defects induced the charge transfers, displaying an enhanced interfacial polarization. At 15 wt.%, the minimum reflection loss of the obtained sample at 2.5 mm reaches −47.56 dB, and the effective absorption bandwidth spans 4.40 GHz, nearly covering the full X band. Additionally, the assembly device testing demonstrates their excellent self‐cleaning, heat‐insulation, flame retardancy, and infrared stealth properties. This work presents a new perspective on the synergistic effect of structure and components on electromagnetic wave absorption performance and provides a new approach for preparing lightweight and high‐performance MOF‐based electromagnetic wave absorbing materials.