bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of pressure annealing on formation of light‐emitting Si nanocrystals in Si rich SiO2
Authors: Kachurin G. A. , Cherkova S. G. , Marin D. V. , Misiuk A. , Yanovitskaya Z. S. , Jedrzejewsky J. , Balberg I.
Published: October 2008

Four types of Si rich SiO2 layers on the Si substrates have been prepared by Si ion implantation or by magnetron co‐sputtering of the Si and SiO2 targets. The types differed from each other in the contents of excess Si, which were about 5 at%, 15 at%, 25 at% and 35 at%. High temperature (up to 1100 °C) anneals of the samples were performed in neutral ambient under normal or elevated (up to 1.5 GPa) hydrostatic pressures. Photoluminescence spectroscopy, Raman scattering and electron diffraction were used for the characterizations. For the lowest concentration of the excess Si the high‐pressure annealing prevents the formation of the light‐emitting Si nanocrystals, but stimulates an appearance of the centers luminescing in the visible range. These centers are believed to be numerous Si nanoclusters, segregated from the oxide network. Increase in Si content provides during the high‐pressure anneals the formation of the quantum‐size Si nanocrystals able to emit strong PL near the wavelength of 800 nm. The effect of the high‐pressure annealing is ascribed to the enhanced energetically favorable segregation of Si from the oxide network. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electron–phonon interaction in zinc oxide. Plasmon–optical phonon coupled modes
Authors: Husanu Adrian‐Marius
Published: October 2008

The effects of the electron–phonon interaction in zinc oxide depending on the free conduction band electron concentration are investigated. In n‐doped polar semiconductors, as the free carrier concentration is increased, the plasmonic mode associated to charge density fluctuations gradually approaches its frequency to the optical phonon ones. As a consequence, their interaction is materialized in coupled mode oscillations. Using a dielectric continuum model, applying the equation of motion technique for the operator associated to charge density fluctuations in ZnO, and taking into account the supplementary constraints introduced by its uniaxial symmetry, the response function of the system is obtained. In polar semiconductors with cubic crystalline structure there are two plasmon‐optical phonon coupled modes. It is shown that in ZnO, three such coupled modes appear. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stability and electronic properties of rhenium sulfide nanotubes
Authors: Enyashin Andrey N. , Popov Igor , Seifert Gotthard
Published: October 2008

The structural properties, the stability and the electronic properties of single‐walled ReS2 nanotubes are studied for the first time using the density‐functional tight‐binding method (DFTB). It is found, that the properties of these nanotubes are determined essentially by the electronic structure causing unique character of intralayer metal–metal bonding within their walls, which evokes their semiconducting character and the highest stiffness after carbon and BN nanotubes. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A model of ionization equilibrium and Mott transition in boron doped crystalline diamond
Authors: Poklonski N. A. , Vyrko S. A. , Poklonskaya O. N. , Zabrodskii A. G.
Published: October 2008

The screening of an impurity ion in diamond by both the holes hopping via boron atoms in charge states (0) and (–1) and the holes of the valence band is calculated in the Debye–Hückel approximation. It is shown that a decrease of the ionized boron atom affinity to valence band hole is determined by its screening. An expression for the dependence of differential thermal ionization energy E1 of boron atoms on their concentration N is obtained in the quasiclassical approximation. Calculated dependence of valence band hole concentration p on N agrees with known experimental data, when the contribution of hopping conductivity to Hall effect may be neglected. A probability density function of the impurity ions and the valence band holes distribution over the crystal is assumed to be Poisson‐like, while their electrostatic potential energy distribution is taken to be normal. The calculations of E1(N) and the critical concentrations of boron atoms N = NM for the insulator–metal phase transition (Mott transition) at different compensation ratios are compared with experimental data. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Vibrational analysis of PbHPO4 and PbDPO4 crystals
Authors: Shchur Yaroslav
Published: October 2008

Lattice dynamics simulation of PbHPO4 and PbDPO4 crystals is performed in paraelectric phase within the semi‐empirical approach. The interpretation of experimental Raman spectra is done using the calculated density of states and the dispersion of mean square displacements of constituent atoms. The ferroelectric phase transition caused by proton–phonon and phonon–phonon interactions. The internal bending mode of PO4 tetrahedral groups may be treated as the probable candidate evoking the appearance of spontaneous polarisation. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Phase transition and elasticity of CdO under pressure
Authors: Peng Feng , Chen Dong , Fu Hongzhi , Cheng Xinlu
Published: October 2008

First‐principles calculations of the crystal structures, and phase transition, and elastic properties of cadmium oxide (CdO) have been carried out with the plane‐wave pseudopotential within the generalized gradient approximation in the frame of density functional theory method. The calculated values (for crystal structures) are in good agreement with experimental data as well as with some of the existing model calculations. For CsCl‐type CdO, the dependence of the elastic constants cij, the aggregate elastic modulus (B, G, E), and the elastic anisotropy on the pressure have been investigated. Moreover, the pressure dependences of the Poisson ratio, Debye temperature, and the compressional and shear elastic wave velocities have been investigated for the first time. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Measurement of intraexcitonic transition signatures via THz time‐domain spectroscopy: A GaAs/(AlGa)As – (GaIn)As/GaAs comparison
Authors: Grunwald T. , Jung T. , Köhler D. , Koch S.W. , Khitrova G. , Gibbs H.M. , Hey R. , Chatterjee S.
Published: October 2008

In this article we present our results on Thzspectroscopy of intra‐excitonic transitions. Especially, properties of different III‐V multi quantum well systems are investigated. After an introduction to the methodology of THz Time‐Domain Spectroscopy, results for both a GaAs/(AlGa)As and a (GaIn)As/GaAs multi quantum well structure are presented. We find good agreement with previous experiments [1,2] for the GaAs/(AlGa)As structure, while the (GaIn)As/GaAs structure behaves significantly different. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Prediction of visibility and aerosol within the operational Met Office Unified Model. II: Validation of model performance using observational data
Authors: Haywood Jim , Bush Mike , Abel Steven , Claxton Bernie , Coe Hugh , Crosier Jonathan , Harrison Mark , Macpherson Bruce , Naylor Mark , Osborne Simon
Published: October 2008

The operational version of the Met Office Unified Model forecasts aerosol and visibility products, as described in Part I. The modelling relies on parametrizations for the aerosol size distribution which account for the coagulation of aerosols into the accumulation mode, and for the hygroscopic uptake of water by aerosols. Aircraft and surface‐based measurements are used to assess these parametrizations and to assess the performance of the modelled aerosol mass mixing ratio and visibility. Measurements of aerosol chemical composition with an airborne aerosol mass spectrometer suggest that much of the aerosol is a complex mixture of sulphate, nitrate and organic material, rather than ammonium sulphate alone, as assumed in the model. Some significant improvements can be made to the hygroscopic parametrizations, along with more minor adjustments to the aerosol size distribution, and aerosol extinction efficiency. Comparisons of the measured aerosol mass mixing ratio reveal measurement–model agreement within a factor of two for the four cases investigated here, while comparisons of visibility reveal a systematic bias to low visibilities in the model, particularly in clean atmospheric conditions. Formulations and strategies to improve the model are suggested. Copyright © 2008 Royal Meteorological Society and Crown Copyright, 2008
Analysis of the 26 July 2005 heavy rain event over Mumbai, India using the Weather Research and Forecasting (WRF) model
Authors: Kumar Anil , Dudhia J. , Rotunno R. , Niyogi Dev , Mohanty U. C.
Published: October 2008

A case‐study of the 26 July 2005 Mumbai heavy‐rain event that recorded 944 mm rainfall in 24 h with significant spatial variability was carried out using the Weather Research and Forecasting (WRF) model. The event was poorly forecasted by operational models and resulted in large human and economic losses. The present results indicate that the WRF system was able to reproduce the heavy rainfall event and the associated dynamical and thermo‐ dynamical features. A number of experiments were conducted with the WRF model that suggest the highly localized, heavy rain was the result of an interaction of synoptic‐scale weather systems with the mesoscale, coastal land‐surface features. These experiments indicate that the large‐scale rising motion over the Mumbai region was synoptically forced. Analysis of the model‐simulated intense, but short‐lived, convective rain cells forming in the large‐scale rising motion over Mumbai traces their moisture source to the north and northwesterly flow from the Arabian Sea. Synthetic sensitivity simulations without topography and without a land surface (land replaced with water) show that the large‐scale synoptic flow positioned the low‐pressure system over the Arabian Sea, while the mesoscale land‐surface (including topography and latent heating) feedback modulated the location and intensity of the rain by changes in the winds and regional moisture convergences. Another important feature captured in the high‐resolution model analysis is the formation of a mesoscale vortex over Mumbai that appears to have enhanced the conditions for localized, heavy rainfall over Mumbai. Copyright © 2008 Royal Meteorological Society
Spontaneous Formation of Vertical Magnetic‐Metal‐Nanorod Arrays During Plasma‐Enhanced Atomic Layer Deposition
Authors: Lee Han‐Bo‐Ram , Gu Gil Ho , Son Jong Yeog , Park Chan Gyung , Kim Hyungjun
Published: October 2008

A novel fabrication method of Co and Ni metal nanorods (NRs) without catalyst or template, based on the spontaneous formation of NRs during plasma‐enhanced atomic layer deposition (PE‐ALD) is developed. Pure Co and Ni NRs 9–10 nm in diameter are synthesized on SiO2 and Si substrates by using metal–organic precursors and an NH3 plasma mixed with a suitable amount of SiH4 as a reactant. The lengths of the NRs are controlled on the nanometer scale by changing the number of PE‐ALD growth cycles. Superconducting quantum interference device magnetometer measurements confirm the magnetic anisotropy of Co NRs caused by shape anisotropy.
Amino Acid Additives Effects on Sweet Potato Starch Thermal Properties
Authors: Lockwood Stephanie , King Joan M.
Published: October 2008

This study assessed the effects of amino acid additives, aspartic acid, leucine, lysine, and methionine, on the thermal characteristics of white‐fleshed and orange‐fleshed Beauregard sweet potato starches. The orange‐fleshed sweet potato (OFSPS) starch began to gelatinize at a lower temperature (56.8°C) than the white‐fleshed sweet potato starch (WFSPS) (70.1°C), but the two starches needed the same amount of energy to gelatinize. Lysine increased the gelatinization temperature of the OFSPS. The addition of leucine, aspartic acid, and methionine had no apparent impact on the OFSPS. The addition of lysine or aspartic acid increased the gelatinization temperatures of the WFSPS. Overall, the two starches used were more affected by charged amino acids than by the neutral ones.
Centralized adaptive load shedding methods to enhance power system voltage stability margins
Authors: Sanaye‐Pasand M. , Seyedi H.
Published: October 2008

In this paper, several centralized adaptive methods to determine the best location of loads to be shed, during under‐frequency conditions, are proposed. The objective of these methods is to enhance voltage stability margins of the power system. Sometimes, after initial frequency drop due to some abnormal events, system frequency might return to its acceptable values, however, the system eventually becomes unstable due to voltage problems. Therefore, enhancement of voltage stability margins may help the system to preserve its stability following severe combinational disturbances. In the proposed algorithms, selection of loads to be shed depends on the location of the disturbance. The decision‐making system in the control center selects appropriate loads to be shed based on the location of the tripped generator. The proposed methods are tested using two different power systems. Complete distributed models of the power systems are used in this work. The effect of the proposed methods in enhancing voltage stability margins are verified by several simulations under different operating conditions. The performances of these adaptive methods are compared with one another and also with the conventional method. Finally, time domain analysis verifies performance of the proposed methods. Copyright © 2008 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Statistical analysis related to impulse tests for self‐restoring insulation
Authors: Komori Yoshio
Published: October 2008

For dielectric tests with impulse voltage, some statistical methods with the step‐up procedure have been recently proposed. In the present paper, the methods are reconsidered from the viewpoint of statistical independence concerning disruptive discharges. As a result, modified methods with the step‐up procedure or with the up‐and‐down procedure are proposed for self‐restoring insulation, and it is shown that they have good properties in the maximum likelihood estimation for the mean and the standard deviation of a normal distribution. Copyright © 2008 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
N′‐acryloyl benzhydrazide as a thermal stabilizer for rigid poly(vinyl chloride)
Authors: Mohamed Riham R.
Published: October 2008

N′‐Acryloyl benzhydrazide (ABH) was examined as a thermal stabilizer and costabilizer for rigid poly(vinyl chloride) (PVC) in air at 180°C. Its high stabilizing efficiency was shown by its high thermal stability value (Ts) when compared with those of two common reference stabilizers used industrially, dibasic lead carbonate (DBLC) and a calcium–zinc soap. Blending this organic stabilizer with the reference stabilizers in different ratios had synergistic effects on both the thermal stability and the extent of discoloration of the PVC. The Ni2+ complex of ABH gave better thermal stability and lesser discoloration than the parent organic stabilizer. Also, blending that complex with DBLC in different ratios gave better stability and lower discoloration. Thermogravimetric analysis confirmed the improved stability of PVC in the presence of the ABH stabilizer. J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers.
Prediction, location, collection and transport of jellyfish (Cnidaria) and their polyps
Authors: Pierce Justin
Published: October 2008

With growing interest in research and display of living jellyfish workers are realizing the difficulty in obtaining and maintaining a healthy collection consistently. This report identifies the causes for the uncertainty in locating specimens and summarizes the latest technology, techniques and avenues for acquiring jellyfish for captive maintenance. Responsibility inherent with jellyfish transport for the prevention of incidental escape is also discussed. Zoo Biol 28:163–176, 2009. © 2008 Wiley‐Liss, Inc.
Trace-based derivation of a scalable lock-free stack algorithm
Authors: Groves Lindsay , Colvin Robert
Published: October 2008

We show how a sophisticated, lock-free concurrent stack implementation can be derived from an abstract specification in a series of verifiable steps. The algorithm is based on the scalable stack algorithm of Hendler et al. (Proceedings of the sixteenth annual ACM symposium on parallel algorithms, 27–30 June 2004, Barcelona, Spain, pp 206–215), which allows push and pop operations to be paired off and eliminated without affecting the central stack, thus reducing contention on the stack, and allowing multiple pairs of push and pop operations to be performed in parallel. Our algorithm uses a simpler data structure than Hendler, Shavit and Yerushalmi’s, and avoids an ABA problem. We first derive a simple lock-free stack algorithm using a linked-list implementation, and discuss issues related to memory management and the ABA problem. We then add an abstract model of the elimination process, from which we derive our elimination algorithm. This allows the basic algorithmic ideas to be separated from implementation details, and provides a basis for explaining and comparing different variants of the algorithm. We show that the elimination stack algorithm is linearisable by showing that any execution of the implementation can be transformed into an equivalent execution of an abstract model of a linearisable stack. Each step in the derivation is either a data refinement which preserves the level of atomicity, an operational refinement which may alter the level of atomicity, or a refactoring step which alters the structure of the system resulting from the preceding derivation. We verify our refinements using an extension of Lipton’s reduction method, allowing concurrent and non-concurrent aspects to be considered separately.
Coronoid Fixation Using Suture Anchors
Authors: Clarke Sylvan E. , Lee Sue Y. , Raphael James R.
Published: October 2008

Fractures of the coronoid process of the ulna generally occur in relatively high-energy injuries and are commonly associated with injuries to other structures around the elbow. Damage to the coronoid process in addition to other elbow structures may complicate treatment. Several approaches have been used in the management of coronoid process fractures. This paper reports a method of coronoid process fracture fixation using suture anchors.
New isoperimetric estimates for solutions to Monge–Ampère equations
Authors: Brandolini B. , Nitsch C. , Trombetti C.
Published: October 2008

We prove some sharp estimates for solutions to Dirichlet problems relative to Monge–Ampère equations. Among them we show that the eigenvalue of the Dirichlet problem, when computed on convex domains with fixed measure, is maximal on ellipsoids. This result falls in the class of affine isoperimetric inequalities and shows that the eigenvalue of the Monge–Ampère operator behaves just the contrary of the first eigenvalue of the Laplace operator.
Gene expression profiling of human hibernating myocardium: Increased expression of B‐type natriuretic peptide and proenkephalin in hypocontractile vs normally‐contracting regions of the heart
Authors: Prasad Sanjay K. , Clerk Angela , Cullingford Timothy E. , Chen Alexander W.Y. , Kemp Timothy J. , Cannell Timothy M. , Cowie Martin R. , Petrou Mario
Published: October 2008

A greater understanding of the molecular basis of hibernating myocardium may assist in identifying those patients who would most benefit from revascularization. Paired heart biopsies were taken from hypocontractile and normally‐contracting myocardium (identified by cardiovascular magnetic resonance) from 6 patients with chronic stable angina scheduled for bypass grafting. Gene expression profiles of hypocontractile and normally‐contracting samples were compared using Affymetrix microarrays. The data for patients with confirmed hibernating myocardium were analysed separately and a different, though overlapping, set (up to 380) of genes was identified which may constitute a molecular fingerprint for hibernating myocardium. The expression of B‐type natriuretic peptide (BNP) was increased in hypocontractile relative to normally‐contracting myocardium. The expression of BNP correlated most closely with the expression of proenkephalin and follistatin 3, which may constitute additional heart failure markers. Our data illustrate differential gene expression in hypocontractile and/hibernating myocardium relative to normally‐contracting myocardium within individual human hearts. Changes in expression of these genes, including increased relative expression of natriuretic and other factors, may constitute a molecular signature for hypocontractile and/or hibernating myocardium.
Prevalence of Dating Partner Violence and Suicidal Ideation Among Male and Female University Students Worldwide
Authors: Chan Ko Ling , Straus Murray A. , Brownridge Douglas A. , Tiwari Agnes , Leung W. C.
Published: October 2008

This paper presents findings from the International Dating Violence study regarding the prevalence of physical assault, sexual coercion, and suicidal ideation among university students and explores the relationships between suicidal ideation and dating violence. Nearly 16,000 university students from 22 sites in 21 countries were recruited through convenience sampling. The results showed that although there were large differences between countries, the lowest rates of dating violence were still quite high. Male and female students were remarkably similar in the proportion of those who physically assaulted a partner or reported being a victim of sexual coercion. Correlation analysis revealed that perpetrators and victims of physical assault had an increased rate of suicidal ideation. Depression accounted for the relationship between dating violence and suicidal ideation. This study highlights a need for the development of universal screening and targeted services for violence, depression, and suicide prevention.
Rural Mothers Experiencing the Stress of Intimate Partner Violence or Not: Their Newborn Health Concerns
Authors: Ellis Kathleen K. , Chang Chiunghsin , Bhandari Shreya , Ball Katharine , Geden Elizabeth , Everett Kevin D. , Bullock Linda
Published: October 2008

Pregnancy and the postpartum period is a time of great physical, psychological, and emotional upheaval. Women who experience intimate partner violence experience more depression and anxiety and a higher risk of adverse pregnancy outcomes (such as those related to the abuse). While the literature supports the presence of increased health care utilization for abused women, there is little information on the way that these mothers seek medical care for their infants. This secondary analysis is part of a larger study on smoking cessation in low‐income, rural pregnant women called Baby Behavioral Education Enhancement of Pregnancy (Baby BEEP). Women (N = 616) were classified as abused or not abused based on their answers to the Abuse Assessment Screen. At 6 weeks postdelivery, each woman was asked, “Has your baby had any problems that you talked to the doctor or nurse about?” The abused women (n = 211) sought health care advice significantly more often than the nonabused women (n = 405; Pearson χ2 = 4.89; P = .027). Stress scores were elevated for all women in the study, but women categorized as abused experienced significantly more stress (P < .001).
Perceived Changes in Health and Safety Following Participation in a Health Care–Based Domestic Violence Program
Authors: Hathaway Jeanne E. , Zimmer Bonnie , Willis Georgianna , Silverman Jay G.
Published: October 2008

This descriptive study explores perceived changes in health and safety and the potential process by which these changes occur. Forty‐nine women experiencing intimate partner abuse participated in a health care–based domestic violence (DV) advocacy program for 6 months or more. An analysis of structured interviews in English and Spanish found that the majority of participants perceived positive changes in their personal safety and emotional health because of their involvement in the program. Some participants also perceived improvements in their physical health, unhealthy coping behaviors (e.g., overeating and smoking), and health care following program involvement. Participants' responses suggest a process of change whereby DV advocacy services first contribute to improved safety and emotional health, which then facilitates behavioral changes. Behavioral changes may subsequently contribute to improvements in physical health, which may also benefit emotional health. Longitudinal evaluations are needed to evaluate the impact of DV advocacy and other interventions for partner abuse on women's health and safety over time.
A Postfunctionalist Theory of European Integration: From Permissive
Consensus to Constraining Dissensus
Authors: Hooghe Liesbet , Marks Gary
Published: October 2008

Preferences over jurisdictional architecture are the product of three irreducible
logics: efficiency, distribution and identity. This article substantiates the
following claims: (a) European integration has become politicized in elections
and referendums; (b) as a result, the preferences of the general public and of
national political parties have become decisive for jurisdictional outcomes; (c)
identity is critical in shaping contestation on Europe.
A microstep control approach for a millimeter-sized omni-directional mobile microrobot actuated by 3-mm-electromagnetic micromotors
Authors: Li Jianghao , Li Zhenbo , Chen Jiapin
Published: October 2008

This paper presents a novel microstep control approach for improving the positioning precision of a millimeter-sized omni-directional mobile microrobot. The microrobot that is designed for microassembly in a microfactory is driven by three electromagnetic micromotors. The structures of both the microrobot and the micromotor are described in the paper. The torque vectors synthesis method (TVSM) is developed and the torque self-balance principle (TSBP) is employed to realize the microstep control. The control circuit that needs a complex digital logic is devised with a complex programmable logic device (CPLD). The experiments using a hard disk and the real microrobot demonstrated the validity and performance of TVSM and TSBP. And the angular step precision of the microrobot is increased by three times compared to the normal control.
Transactional events
Authors: DONNELLY KEVIN , FLUET MATTHEW
Published: October 2008

Concurrent programs require high-level abstractions in order to manage complexity and enable compositional reasoning. In this paper, we introduce a novel concurrency abstraction, dubbedtransactional events, which combines first-class synchronous message passing events with all-or-nothing transactions. This combination enables simple solutions to interesting problems in concurrent programming. For example, guarded synchronous receive can be implemented as an abstract transactional event, whereas in other languages it requires a non-abstract, non-modular protocol. As another example, three-way rendezvous can be implemented as an abstract transactional event, which is impossible using first-class events alone. Both solutions are easy to code and easy to reason about.

The expressive power of transactional events arises from a sequencing combinator whose semantics enforces an all-or-nothing transactional property – either both of the constituent events synchronize in sequence or neither of them synchronizes. This sequencing combinator, along with a non-deterministic choice combinator, gives transactional events the compositional structure of a monad-with-plus. We provide a formal semantics for transactional events and give a detailed account of an implementation.
Du syriaque au latin par l'intermédiaire de l'arabe: leKunnāšde Yūḥannā ibn Sarābiyūn
Authors: Troupeau Gérard
Published: October 2008

This treatise of medicine by Yühannā ibn Sarābiyūn, written in Syriac in the 8th century, translated into Arabic in the 10th century and then into Latin in the 12th century, is a typical example of the transmission of Hippocratic medicine from the Arabic East to the Latin West in the Middle Ages. However, while the complete Latin translation of Gerard of Cremona has reached us, we have only fragments of the Arabic text, dispersed in five manuscripts preserved in four European libraries.

In the first part we shall try to establish the biographical information about the author and the four translators of his treatise from Syriac to Arabic. In the second part we shall study the Arabic fragments of the Paris manuscript and the two Escorial manuscripts, first by examining their language, and then by comparing them to the Latin translation.
The Aš‘arite Ontology: I Primary Entities
Authors: Frank Richard M.
Published: October 2008

The present study seeks to lay out the most basic elements of the ontology of classical Aš‘arite theology. In several cases this requires a careful examination of the traditional and the formal lexicography of certain key expressions. The topics primarily treated are: (1) how they understood “Being/ existence” and “being/existent” and essential natures; the systematic exploitation of the equivocities of certain expressions (e.g., ḫaqīqa, ḫadd, ma‘na) within a general context in which other than words there are no universals proves to be elegant as well as insightful; (2) the basic categories of primary entities: independant beings and nonindependant beings, (a) created and (b) uncreated, the equivocity of “being/existent” as predicated of contingent entities on the one hand and of God and His attributes on the other, and certain problems that arise because of the rigid application of the system's underlying analytic principles.
A New Hebrew Passage from theTheology of Aristotleand its Significance
Authors: Langermann Y. Tzvi
Published: October 2008

On some of the end-leaves of a Bible manuscript someone has copied out a passage from theTheology of Aristotlein Hebrew translation. The passage deals with the immunity of person of intellect from magical manipulation. No other copies of this passage in Hebrew are known to exist. The dependence of the translator upon the so-called “long version” of theTheology, specifically the copy in St Petersburg, is demonstrated, and it is suggested that the translator may be Shem Tov ibn Falaquera. The passage differs significantly from other versions of theTheology, and from Plotinus, in placing intellectual achievement ahead of ethical perfection in the scale of values.
L'idée de la sagesse et sa fonction dans la philosophie des 4e et 5e siècles
Authors: Jolivet Jean
Published: October 2008

Starting from the Greek definition of philosophy as the love of wisdom, and from the semantic richness of the Arabic wordḥikma, several fourth- and fifth-century writers tried to establish the position of philosophy in the Islamic cultural system by identifying it with wisdom. For them this wisdom is tantamount to the ‘eternal wisdom’ recorded in the ancient books and taught by the prophets. Philosophers are described as the prophets' disciples or witnesses. However, depicting philosophy as eternal wisdom only gives the discipline an illusory advantage. Ultimately it reduces it to pure repetition and therefore precludes any change.
Ibrāhīm ibn Sinān: On Analysis and Synthesis
Authors: Bellosta Hélène
Published: October 2008

This paper is devoted to Ibn Sinān's treatise on analysis and synthesis. Ibn Sinān's text deals with two distinct, though closely related, subjects. First he considers the classification of problems, founded on the logical criteria which are the number and degree of indetermination of the solutions and (though in a less relevant way) the number of hypotheses and their possible independence. This classification does not replace the Hellenistic one, which remains relevant insofar as it purports to solve geometrical problems, but complements it and has a different frame of reference, applying principally to algebra, that new born science. Ibn Sinān's classification will be taken up and used by algebraists. Secondly, the text presents a new way of setting out analysis and synthesis, so that they become exactly reciprocal. This leads Ibn Sinān to bestow more importance on the role played by analysis in the course of the proof, the only role left to synthesis being to check that all implications involved in the course of analysis are in fact equivalences. This method will prove to be productive in algebra too, so much so that some algebraists will explicitly identify algebra with analysis.
The Science ofKalām
Authors: Frank Richard M.
Published: October 2008

Our intention here is to present the essential character of classical, sunnīkalāmwithin a strictly formal perspective and to set out its basic aspects. It was conceived by themutakallimīnas a rational, conceptual, and critical science and, althoughkalāmdiffered in a number of basic concepts and constructs and in its analytic system, the topical organisation of the major compendia parallels that of metaphysics as understood in the contemporary Aristotelian tradition. The debates betweenkalāmandfalsafaneed to be examined within this context.Kalām, however, is theological in the strict sense of the term and it is as such that its problematic and its procedures are primarily to be understood. Thus seen, the object ofkalāmis to rationalise the cognitive content presented to Believers in the symbolic language of the koranic revelation. It has, then, four principal tasks, sc, to conceptualise, to order, to explain, and where possible to justify the primary doctrines of the community whose belief is held to be normative. Within this framework the differences that characterise the major schools as such and the various tendencies of individual masters within each school may readily be brought to light.
L'optique d'ibn al-haytham et la tradition ptoléméenne
Authors: Simon Gérard
Published: October 2008

Quand on compare l'Optique d'Ibn al-Haytham (Alhazen) à celle de Ptolémée, on rencontre des innovations à coup sûr capitales, et qui chacune mériterait une analyse particulière: étude expérimentale de la propagation rectiligne de la lumière, nouvelle théorie de la vision fondée sur la réception dans l'œil de rayons lumineux, recherche du lien entre l'anatomie de 1'œil et sa fonction optique, preuve expérimentale que la réfraction joue un rôle important dans la vision, et j'en passe: les dimensions d'un article de revue n'y suffiraient pas. Aussi bien mon but est-il plus global et plus synthétique. Il consiste à tenter de faire le point sur ce qu'est devenue, après Ibn al-Haytham, l'insertion de l'optique dans le système des savoirs qui lui sont connectès, en comparant cette insertion à ce qu'elle était au temps de Ptolémée, c'est-à-dire dans l'œuvre de référence (plus encore que celle d'Euclide et du pseudo-Euclide) reçae et travaillée par lui.
A Non-Ptolemaic Lunar Model From Fourteenth-Century Central Asia
Authors: Dallal Ahmad
Published: October 2008

As early as the ninth century, Muslim astronomers started refining the Ptolemaic astronomy which, by this time, had been fully adopted as the framework of their research. Already, in the early part of this century, refinements were based on improved observational techniques, and included a variety of phenomena such as the length of the seasons, the solar equation, mean motion parameters, and many others.
Al-Kindī's Commentary on Archimedes' ‘The Measurement of the Circle’
Authors: Rashed Roshdi
Published: October 2008

The author examines the relationship between mathematics and philosophy in the works of al-Kindī, and suggests that the real character of his contribution will become clear only when we restore to mathematics their proper role in his philosophy. The recently discovered treatise of al-Kindī on the approximation of π, of which the author gives the editio princeps here, throws important new light on al-Kindī's knowledge of mathematics, and on the history of the transmission of The Measurement of the Circle of Archimedes. The author shows that al-Kindī's commentary on the third proposition of the Measurement of the Circle was written before 857, at the same time if not before that of the Banū Mūsā, and that it was one of the sources of the Florence Versions, the Latin commentary on the same proposition.
Al-Qushjī's Reform of the Ptolemaic Model for Mercury
Authors: Saliba George
Published: October 2008

In this article the author analyzes a fifteenth-century Arabic reform of the Ptolemaic model for Mercury. The author of the reform was the Central Asian – Ottoman astronomer ‘Alā” al-Dīn al-Qushjī (d. 1474 A.D.) who, in his youth, had been instructed in the mathematical sciences by none other than the famous Central Asian monarch Ulugh Beg (1394–1449). Although the astronomers of Ulugh Beg's circle are known to have produced extensive astronomical Persian tables, no one other than Qushjī has been yet identified to have produced a theoretical text devoted to the criticism, let alone the reform, of the Ptolemaic mathematical planetary models. The present article on Qushji's reform of the Ptolemaic model for Mercury includes a critical first edition of Qushji's Arabic text, an English translation, and a historical and technical commentary.
Ṯābit B. Qurra and Arab Astronomy in the 9th Century
Authors: Morelon Régis
Published: October 2008

Ṯābit b. Qurra is especially known as a mathematician, but his work in astronomy is also important. This article reviews his eight surviving astronomical treatises, as well as relevant fragments of his lost works cited by later authors in Arabic and Latin. We conclude that, as an active participant in the scientific movement of 9th-century Baghdad, Ṯābit played a crucial role in the establishment of astronomy as an exact science. The argument is based on an assessment of his contribution in three areas: the relationship between observation and theory, the “mathematization” of astronomy, and the relationship between “mathematical” astronomy and “physical” astronomy.
Averroes'De CaeloIbn Rushd's Cosmology in his Commentaries on Aristotle'sOn the Heavens
Authors: Endress Gerhard
Published: October 2008

Averroes defended philosophy by returning to the true Aristotle. For this purpose, Aristotle's book “On the Heaven,” in which he explained the eternity, uniqueness and movement of the universe, occupied a place of special importance. But the Aristotelian philosopher had a hard time holding his own in the face of contradictions within the book and with respect to Aristotle's later works. In his early Compendium, later Paraphrase, and final Long Commentary ofDe Caelo, Ibn Rushd continued the efforts of the Hellenistic commentators in order to integrate all the elements of his doctrine into a unified system, to harmonize his early cosmology with his later Metaphysics – the early doctrine of natural movement of the elements, and of the self-moving star-souls (a Platonic element), with the doctrine of potency and actuality and the theory of the First Mover – and to uphold his models of homocentric planetary spheres against the mathematical paradigm of Ptolemaic astronomy. By insisting throughout on demonstrative arguments based on rational principles, he asserted the philosophers' claim to irrefutable truth.
Ibn al-Haytham's Universal Solution for Finding the Direction of the Qibla by Calculation
Authors: Dallal Ahmad S.
Published: October 2008

This paper presents an edition of al-Hasan ibn al-Ḥasan ibn al-Haytham's (d. 1040) treatise, Qawl fi samt al-qibla bi-al-ḥisāb (on finding the azimuth of the Qibla by calculation) with translation and commentary. In it Ibn al-Haytham provides a universal method for finding the direction of the qibla at any location on the surface of the earth by using spherical trigonometry and accurate calculation. Ibn al-Haytham's computational solution has not been studied before, and it has often been confused with another work of his in which he uses an analemma construction to solve the problem of the qibla graphically. As a result of this confusion, contemporary scholars have mistakenly attributed the first universal solution of the qibla problem to Jamshīd al-Kāshī (15th century), some four centuries after the introduction of this method by Ibn al-Haytham. The present treatise represents an important juncture in the history of the development of mathematics of the qibla, and sheds more light on the contributions of one of the most important scientists of medieval Islam.
Why is the Sea Salty? The Discussion of Salinity in Hebrew texts of the Thirteenth Century
Authors: Fontaine Resianne
Published: October 2008

The thirteenth-century Hebrew texts that discuss salinity all ultimately go back to Aristotle's treatment of the subject in theMeteorology. However, in these Hebrew texts the question of what exactly makes the sea salty is answered in diverging ways. The oldest of them, theOtot ha-Shamayim(1210), being the Hebrew translation of the Arabic paraphrase of theMeteorology, proposes various causes of the sea's salinity, to wit, the dry exhalation, the action of heat, and the admixture of an earthy substance. This is due partly to Aristotle's own ambiguity, and partly to the fact that his Greek commentators interpreted his words in different ways. Two later encyclopedias, theMidrash ha-Hokhma(c. 1245) and theDe'ot ha-Philosofim(c. 1275?) base their expositions of salinity on Ibn Rushd, whose two commentaries on theMeteorologycontain various theories. The first encyclopedia opts for the action of heat as the major cause in producing saltiness, whereas the second attempts to explain in which way the various causes are interrelated by advisedly combining Ibn Rushd's accounts.
Le calcul du maximum et la “dérivée” selon Sharaf al-Dīn al-Ṭūsī
Authors: Farès Nicolas
Published: October 2008

The importance of the Treatise on equations by Sharaf al-Dīn al-Ṭūsī (12th century) has been brought to our attention by R. Rashed (1974, 1986), who underlined the analytical aspects of this essentially algebraic work. Following Rashed, this article concentrates on one of these analytical concepts, namely the maximum of a polynomial expression f(x) of degree 3. The purpose is to clarify the techniques that led al-Ṭūsī, when computing the maximum of f(x), to systematically display algebraic equations equivalent to f(x) = 0. By demonstrating that al-Ṭūsī's essentially algebraic proofs were also based on analytical procedures, we show that the presence of these equations was not fortuitous, but resulted from a correct understanding of the maximum of f(x). The accompanying geometrical representations were primarily for illustration.
Les cercles tangents d'al-Qūhī
Authors: Abgrall Philippe
Published: October 2008

This article presents the Arabic text of al-Qūhī's short geometric treatise, The Book of the centres of the tangent circles on lines, by the method of analysis (Xe century), with translation and a mathematical commentary. In this treatise al-Qūhī solves by analysis an ordered set of eight problems where the goal is to locate, on a given line, the centre of a circle which is tangent to two given elements, which may be points, straight lines or circles. For example, in the first problem he wanted to find the centre of a circle which contains two given points. In fact, al-Qūhī establishes the locus of the solutions, and this locus can be a straight line or a conic. The treatise is reminiscent of one of the purposes of al-Qūhī's work on the perfect compass (an instrument to draw conics by moving continuously), namely to assign to the conics the status of regular lines.
L'histoire des nombres amiables: le témoignage des textes hébreux médiévaux
Authors: Lévy Tony
Published: October 2008

This article analyzes new material on the history of the amicable numbers. It discusses Hebrew texts which throw new light on the diffusion in Medieval Europe of Ṯābit ibn Qurra's (9th century) work. We find Ṯābit's theorem on amicable numbers in a Hebrew translation, made in Saragossa in 1395, of an arithmetical commentary written by Abū al-Ṣalt al-Andalusī (ca. 1068–1134), and also in an original Hebrew text probably written by the Jewish Provençal scholar Qalonymos ben Qalonymos (1287 – after 1329). These texts lend strong support to the surmise that the Arabic tradition concerning amicable numbers could not have remained unknown to European mathematicians before the work of Descartes and Fermat in the 17th century.
Stoic Physics in the Writings of R. Saadia Ga'on al-Fayyumi and its Aftermath in Medieval Jewish Mysticism
Authors: Freudenthal Gad
Published: October 2008

R. Saadia Ga'on (882–942) of Baghdad sought to avoid anthropomorphism by arguing that scriptural phrases which seem to ascribe materiality to the Deity in fact refer not to God Himself, but rather to a created entity, God's Glory, which he described as a very tenuous “air.” This paper argues that Saadia's conception of a quasi-divine “air” through which God accomplishes His acts in the material world is heavily indebted to the Stoic theory ofpneuma. It follows that the immanentist theology ofḤasidey Ashkenaz(German Pietists), which is known to have been substantially influenced by Saadia,in fineis also indebted to Stoic philosophy and physics.
Mineralogy, Botany and Zoology in Medieval Hebrew Encyclopaedias
Authors: Zonta Mauro
Published: October 2008

There are three principal philosophical-scientific encyclopaedias written in Hebrew during the Middle Ages: Yehudah ha-Cohen'sMidrash ha-Ḥokmah(1245–1247), Shem Tov ibn Falaquera'sDe'ot ha-Filosofim(ca. 1270) and Gershon ben Shlomoh'sSha'ar ha-Shamayin(end of the 13th century). All three include detailed treatments of zoology, and the last two of botany and mineralogy as well. The principal feature of their treatments is their “theoretical” – not merely “descriptive” – approach: these encyclopaedias do not contain only lists of stones, plants and animals (such as other Arabic and Latin Medieval encyclopaedias), but also attempts at systematization and philosophical arrangement of the various available theories in the fields of mineralogy, botany and zoologyquasciences. An examination of the doctrines and the sources of these texts shows that, while the treatment of zoology relies upon Aristotle's zoological works and, above all, theirCompendiaby Averroes, the treatment of mineralogy and botany reflects the non-Aristotelian theories of theBrethren of Purity(Iḫwān al-Ṣafā'), rather than such texts as pseudo-Aristotle'sDe lapidibusand Nicolaus Damascenus'De plantis. In particular, Falaquera's encyclopaedia represents the most convincing effort to provide a truly scientific discussion of mineralogy and botany, comparable to that of his contemporary Albert the Great, and based upon theBrethren, Avicenna and, maybe, some lost works by Averroes.
Averroes' Use of Examples in his Middle Commentary on the Prior Analytics, and Some Remarks on his Role as Commentator
Authors: Harvey Steven
Published: October 2008

Averroes wrote three kinds of commentaries on the books of Aristotle - epitomes, middle commentaries, and long commentaries - and each kind had its own purposes. His aims may have also differed from text to text. That is, it seems reasonable to assume that he would stick closer to Aristotle in the logical works than, for example, in the metaphysical works. The present study investigates what may be called the “theological aspects” of Averroes' commentaries, and explores the commentary of Averroes that appears least likely to contain such elements, theMiddle Commentary on the Prior Analytics. ThePrior Analyticsis perhaps the most straightforward, even pedantic, of all of Aristotle's writings, and of Averroes' three kinds of commentaries, it is the middle commentaries which are least likely to diverge or digress from the text of Aristotle. The only trace of a religious hand in the commentary is Averroes' use of examples, and, in particular, examples that conclude that “the world is created” and the like. It is argued that Averroes chose these examples to show the traditionalist reading public the falsity of the theologians claims against the logic of the philosophers. The Appendix to the article shows that medieval commentators on Averroes' commentaries were also struck by his “creation of the world” examples.