bluuebunny/crossref_metadata_2025 huggingface dataset:
Describing Groups
Authors: Nies André
Published: December 2007

Two ways of describing a group are considered. 1. A group isfinite-automaton presentableif its elements can be represented by strings over a finite alphabet, in such a way that the set of representing strings and the group operation can be recognized by finite automata. 2. An infinite f.g. group isquasi-finitely axiomatizableif there is a description consisting of a single first-order sentence, together with the information that the group is finitely generated. In the first part of the paper we survey examples of FA-presentable groups, but also discuss theorems restricting this class. In the second part, we give examples of quasi-finitely axiomatizable groups, consider the algebraic content of the notion, and compare it to the notion of a group which is a prime model. We also show that if a structure is bi-interpretable in parameters with the ring of integers, then it is prime and quasi-finitely axiomatizable.
Valuation structure
Authors: Zhu Zhaohui , Pan Zhenghua , Chen Shifu , Zhu Wujia
Published: December 2007

This paper introduces valuation structures associated with preferential models. Based on KLM valuation structures, we present a canonical approach to obtain injective preferential models for any preferential relation satisfying the property INJ, and give uniform proofs of representation theorems for injective preferential relations appeared in the literature. In particular, we show that, in any propositional language (finite or infinite), a preferential inference relation satisfies INJ if and only if it can be represented by a standard preferential model. This conclusion generalizes the result obtained by Freund. In addition, we prove that, when the language is finite, our framework is sufficient to establish a representation theorem for any injective relation.
Unique decomposition in classifiable theories
Authors: Hart Bradd , Hrushovski Ehud , Laskowski Michael C.
Published: December 2007

By a classifiable theory we shall mean a theory which is superstable, without the dimensional order property, which has prime models over pairs. In order to define what we mean by unique decomposition, we remind the reader of several definitions and results. We adopt the usual conventions of stability theory and work inside a large saturated model of a fixed classifiable theory T; for instance, if we write M ⊆ N for models of T, M and N we are thinking of these models as elementary submodels of this fixed saturated models; so, in particular, M is an elementary submodel of N. Although the results will not depend on it, we will assume that T is countable to ease notation.

We do adopt one piece of notation which is not completely standard: if T is classifiable, M0 ⊆ Mi for i = 1, 2 are models of T and M1 is independent from M2 over M0 then we write M1M2 for the prime model over M1 ∪ M2.
Some weak fragments of HA and certain closure properties
Authors: Moniri Morteza , Moniri Mojtaba
Published: December 2007

We show that Intuitionistic Open Induction iop is not closed under the rule DNS(Ǝ1). This is established by constructing a Kripke model of iop + ¬Ly(2y > x), where Ly(2y > x) is universally quantified on x. On the other hand, we prove that iop is equivalent with the intuitionistic theory axiomatized by PA− plus the scheme of weak ¬¬ LNP for open formulas, where universal quantification on the parameters precedes double negation. We also show that for any open formula φ(y) having only y free. (PA−)i ⊢ Lyφ(y). We observe that the theories iop, i∀1 and iΠ1 are closed under Friedman's translation by negated formulas and so under VR and IP. We include some remarks on the classical worlds in Kripke models of iop.
Relation algebra reducts of cylindric algebras and an application to proof theory
Authors: Hirsch Robin , Hodkinson Ian , Maddux Roger D.
Published: December 2007

We confirm a conjecture, about neat embeddings of cylindric algebras, made in 1969 by J. D. Monk, and a later conjecture by Maddux about relation algebras obtained from cylindric algebras. These results in algebraic logic have the following consequence for predicate logic: for every finite cardinal α ≥ 3 there is a logically valid sentence X, in a first-order language ℒ with equality and exactly one nonlogical binary relation symbol E, such that X contains only 3 variables (each of which may occur arbitrarily many times), X has a proof containing exactly α + 1 variables, but X has no proof containing only α variables. This solves a problem posed by Tarski and Givant in 1987.
Two cardinal properties of homogeneous graphs
Authors: Cherlin Gregory , Thomas Simon
Published: December 2007

We analyze the two cardinal properties of definable sets in homogeneous graphs.
On modal logics betweenK × K × KandS5 × S5 × S5
Authors: Hirsch R. , Hodkinson I. , Kurucz A.
Published: December 2007

We prove that everyn-modal logic betweenKnandS5nis undecidable, whenever n ≥ 3. We also show that each of these logics is non-finitely axiomatizable, lacks the product finite model property, and there is no algorithm deciding whether a finite frame validates the logic. These results answer several questions of Gabbay and Shehtman. The proofs combine the modal logic technique of Yankov–Fine frame formulas with algebraic logic results of Halmos, Johnson and Monk, and give a reduction of the (undecidable) representation problem of finite relation algebras.
A classification of intersection type systems
Authors: Bunder M. W.
Published: December 2007

The first system of intersection types. Coppo and Dezani [3], extended simple types to include intersections and added intersection introduction and elimination rules ((ΛI ) and (ΛE) ) to the type assignment system. The major advantage of these new types was that they were invariant under β-equality, later work by Barendregt, Coppo and Dezani [1], extended this to include an (η) rule which gave types invariant under βη-reduction.

Urzyczyn proved in [6] that for both these systems it is undecidable whether a given intersection type is empty. Kurata and Takahashi however have shown in [5] that this emptiness problem is decidable for the sytem including (η). but without (ΛI).

The aim of this paper is to classify intersection type systems lacking some of (ΛI), (ΛE) and (η), into equivalence classes according to their strength in typing λ-terms and also according to their strength in possessing inhabitants.

This classification is used in a later paper to extend the above (un)decidability results to two of the five inhabitation-equivalence classes. This later paper also shows that the systems in two more of these classes have decidable inhabitation problems and develops algorithms to find such inhabitants.
Forcing and stable ordered–union ultrafilters
Authors: Eisworth Todd
Published: December 2007

We investigate the effect of a variant of Matet forcing on ultrafilters in the ground model and give a characterization of those P–points that survive such forcing, answering a question left open by Blass [4]. We investigate the question of when this variant of Matet forcing can be used to diagonalize small filters without destroying P–points in the ground model. We also deal with the question of generic existence of stable ordered-union ultrafilters.
On the Ramseyan properties of some special subsets of 2ωand their algebraic sums
Authors: Nowik Andrzej , Weiss Tomasz
Published: December 2007

We prove the following theorems:

1. IfX⊆ 2ωis aγ-set andY⊆2ωis a strongly meager set, thenX+Yis Ramsey null.

2. IfX⊆2ωis aγ-set andYbelongs to the class ofsets, then the algebraic sumX+Yis anset as well.

3. Under CH there exists a setX∈MGR* which is not Ramsey null.
Deconstructing inner model theory
Authors: Schindler Ralf-Dieter , Steel John , Zeman Martin
Published: December 2007

In this paper we shall repair some errors and fill some gaps in the inner model theory of [2]. The problems we shall address affect some quite basic definitions and proofs.

We shall be concerned with condensation properties of canonical inner models constructed from coherent sequences of extenders as in [2]. Condensation results have the general form: if x is definable in a certain way over a level , then either x ∈ , or else from x we can reconstruct in a simple way.

The first condensation property considered in [2] is the initial segment condition, or ISC. In section 1 we show that the version of this condition described in [2] is too strong, in that no coherent in which the extenders are indexed in the manner of [2], and which is such that L[] satisfies the mild large cardinal hypothesis that there is a cardinal which is strong past a measurable, can satisfy the full ISC of [2]. It follows that the coherent sequences constructed in [2] do not satisfy the ISC of [2]. We shall describe the weaker ISC which these sequences do satisfy, and indicate the small changes in the arguments of [2] this new condition requires.
Local superssimplicity and related concepts
Authors: Casanovas Enrique , Wagner Frank O.
Published: December 2007

We study local strengthenings of the simplicity condition. In particular, we define and study a local Lascar rank, as well as short, low. supershort and superlow theories. An example of a low non supershort theory is given.
More undecidable lattices of Steinitz exchange systems
Authors: Galminas L. R. , Rosenthal John W.
Published: December 2007

We show that the first order theory of the lattice <ω(S) of finite dimensional closed subsets of any nontrivial infinite dimensional Steinitz Exhange System S has logical complexity at least that of first order number theory and that the first order theory of the lattice (S∞) of computably enumerable closed subsets of any nontrivial infinite dimensional computable Steinitz Exchange System S∞ has logical complexity exactly that of first order number theory. Thus, for example, the lattice of finite dimensional subspaces of a standard copy of ⊕ωQ interprets first order arithmetic and is therefore as complicated as possible. In particular, our results show that the first order theories of the lattice (V∞) of c.e. subspaces of a fully effective ℵ0-dimensional vector space V∞ and the lattice of c.e. algebraically closed subfields of a fully effective algebraically closed field F∞ of countably infinite transcendence degree each have logical complexity that of first order number theory.
The relation of recursive isomorphism for countable structures
Authors: Camerlo Riccardo
Published: December 2007

It is shown that the relations of recursive isomorphism on countable trees, groups, Boolean algebras, fields and total orderings are universal countable Borel equivalence relations, thus providing a countable analogue of the Borel completeness of the isomorphism relations on these same classes.
Blowing up the power set of the least measurable
Authors: Apter Arthur W. , Cummings James
Published: December 2007

We prove some results related to the problem of blowing up the power set of the least measurable cardinal. Our forcing results improve those of [1] by using the optimal hypothesis.
PDL has interpolation
Authors: Kowalski Tomasz
Published: December 2007

It is proved that free dynamic algebras superamalgamate. Craig interpolation for propositional dynamic logic and superamalgamation for the variety of dynamic algebras follow.
Defining transcendentals in function fields
Authors: Koenigsmann Jochen
Published: December 2007

Given any fieldK, there is a function fieldF/Kin one variable containing definable transcendental overK, i.e., elements inF / Kfirst-order definable in the language of fields with parameters fromK. Hence, the model-theoretic and the field-theoretic relative algebraic closure ofKinF do notcoincide. E.g., ifKis finite, the model-theoretic algebraic closure ofKin the rational function fieldK(t)isK(t).

For the proof, diophantine ∅-definability ofKinFis established for any function fieldF/Kin one variable, providedKis large, orK×/(K×)nis finite for some integern> 1 coprime tochar K.
Representability in second-order propositional poly-modal logic
Authors: Antonelli G. Aldo , Thomason Richmond H.
Published: December 2007

A propositional system of modal logic issecond-orderif it contains quantifiers ∀pand ∃pwhich, in the standard interpretation, are construed as ranging over sets of possible worlds (propositions). Most second-order systems of modal logic are highly intractable; for instance, when augmented with propositional quantifiers, K, B, T, K4 and S4 all become effectively equivalent to full second-order logic. An exception is S5, which, being interpretable in monadic second-order logic, is decidable.

In this paper we generalize this framework by allowing multiple modalities. While this does not affect the undecidability of K, B, T, K4 and S4, poly-modal second-order S5 is dramatically more expressive than its mono-modal counterpart. As an example, we establish the definability of the transitive closure of finitely many modal operators. We also take up the decidability issue, and, using a novel encoding of sets of unordered pairs by partitions of the leaves of certain graphs, we show that the second-order propositional logic of two S5 modalitities is also equivalent to full second-order logic.
The lazy logic of partial terms
Authors: Gumb Raymond D.
Published: December 2007

The Logic of Partial TermsLPTis a strict negative free logic that provides an economical framework for developing many traditional mathematical theories having partial functions. In these traditional theories, all functions and predicates are strict. For example, if a unary function (predicate) is applied to an undefined argument, the result is undefined (respectively, false). On the other hand, every practical programming language incorporates at least one nonstrict or lazy construct, such as the if-then-else, but nonstrict functions cannot be either primitive or introduced in definitional extensions inLPT. Consequently, lazy programming language constructs do not fit the traditional mathematical mold inherent inLPT. A nonstrict (positive free) logic is required to handle nonstrict functions and predicates.

Previously developed nonstrict logics are not fully satisfactory because they are verbose in describing strict functions (which predominate in many programming languages), and some logicians find their semantics philosophically unpalatable. The newly developed Lazy Logic of Partial TermsLLis as concise asLPTin describing strict functions and predicates, and strict and nonstrict functions and predicates can be introduced in definitional extensions of traditional mathematical theories.LLis “built on top of”LPT. and, likeLPT, admits only one domain in the semantics. In the semantics, for the case of a nonstrict unary functionhin an LL theoryT, we have ⊨Th(⊥) =y↔ ∀x(h(x) = y), where ⊥ is a canonical undefined term. Correspondingly, in the axiomatization, the “indifference” (to the value of the argument) axiomh(⊥) =y↔ ∀x(h(x) = y)guarantees a proper fit with the semantics. The price paid forLL's naturalness is that it is tailored for describing a specific area of computer science, program specification and verification, possibly limiting its role in explicating classical mathematical and philosophical subjects.
Bounded Martin's Maximum, weak Erdӧs cardinals, and ψAc
Authors: Asperó David , Welch Philip D.
Published: December 2007

We prove that a form of the Erdӧs property (consistent with V = L[Hω2] and strictly weaker than the Weak Chang's Conjecture at ω1), together with Bounded Martin's Maximum implies that Woodin's principle ψAC holds, and therefore . We also prove that ψAC implies that every function f: ω1 → ω1 is bounded by some canonical function on a club and use this to produce a model of the Bounded Semiproper Forcing Axiom in which Bounded Martin's Maximum fails.
Rangs et types de rang maximum dans les corps différentiellement clos
Authors: Benoist Franck
Published: December 2007

It is known that in differentially closed fields of characteristic zero, the ranks of stability RU, RM and the topological rank RH need not to be equal. Pillay and Pong have just shown however that the ranks RU and RM coincide in a group definable in this theory. At the opposite, we will show in this paper that the ranks RM and RH of a definable group can also be different, and even lead to non-equivalent notions of generic type.
Core models with more Woodin cardinals
Authors: Steel J. R.
Published: December 2007

In this paper, we shall prove two theorems involving the construction of core models with infinitely many Woodin cardinals. We assume familiarity with [12], which develops core model theory the one Woodin level, and with [10] and [6], which extend the fine structure theory of [5] to mice having many Woodin cardinals. The most important new problem of a general nature which we must face here concerns the iterability of Kc with respect to uncountable iteration trees.

Our first result is the following theorem, a slightly stronger version of which was proved independently and earlier by Woodin. The theorem settles positively a conjecture of Feng, Magidor, and Woodin [2].

Theorem. Let Ω be measurable. Then the following are equivalent:

(a) for all posets,

(b) for every poset,

(c) for every poset ℙ ∈ VΩ, Vℙ ⊨ there is no uncountable sequence of distinct reals in L(ℝ)

(d) there is an Ω-iterable premouse of height Ω which satisfies “there are infinitely many Woodin cardinals”.

It is an immediate corollary that if every set of reals in L(ℝ) is weakly homogeneous, then ADL(ℝ) holds. We shall also indicate some extensions of the theorem to pointclasses beyond L(ℝ), and mice with more than ω Woodin cardinals.
Smooth classes without AC and Robinson theories
Authors: Pourmahdian Massoud
Published: December 2007

We study smooth classes without the algebraic closure property. For such smooth classes we investigate the simplicity of the class of generic structures, in the context of Robinson theories.
Small theories of Boolean ordered o-minimal structures
Authors: Wencel Roman
Published: December 2007

We investigate small theories of Boolean ordered o-minimal structures. We prove that such theories are ℵ0-categorical. We give a complete characterization of their models up to bi-interpretability of the language. We investigate types over finite sets, formulas and the notions of definable and algebraic closure.
Frege's unofficial arithmetic
Authors: Rayo Agustín
Published: December 2007

I show that any sentence ofnth-order (pure or applied) arithmetic can be expressed with no loss of compositionality as a second-order sentence containing no arithmetical vocabulary, and use this result to prove a completeness theorem for applied arithmetic. More specifically. I set forth an enriched second-order languageL. a sentenceofL(which is true on the intended interpretation ofL), and a compositionally recursive transformationTrdefined on formulas ofL, and show that they have the following two properties: (a) in a universe with at least ℶn−2objects, any formula ofnth-order (pure or applied) arithmetic can be expressed as a formula ofL, and (b) for any sentenceofis a second-order sentence containing no arithmetical vocabulary, and
Designing Online Courses to Promote Student Retention
Authors: Dietz-Uhler Beth , Fisher Amy , Han Andrea
Published: December 2007

Although the issue of student retention is a campus-wide one, it is of special interest in online distance learning courses, where retention rates are reported to be lower than in face-to-face classes. Among the explanations and theories of retention rates in online courses, one that struck us as most useful is a structural one, namely, course design. The question we raise is, can online course designs promote student retention? In this article, we report on how we used Quality Matters to design and revise online courses in psychology and statistics. Quality Matters, a research-based initiative, advocates the use of eight general review standards to review online courses. In our psychology and statistics courses, our retention rate across multiple offerings of both courses is approximately 95%.
Computer Use in Undergraduate Health Education Programs
Authors: Brouse Corey H. , Basch Charles E. , Leblanc Michael
Published: December 2007

There is a paucity of research concerning the opinions and roles of Department Chairs pertaining to computer use, yet these individuals are in a key position to influence the curricula. The purpose of this survey was to improve understandings about Department Chairs' opinions and reported practices concerning computer applications in their undergraduate professional preparation programs. The target population for the study was all of the Department Chairs of undergraduate health education or related programs in the United States. The sampling frame was conducted by using the list maintained by the American Alliance of Health, Physical Education, Recreation and Dance (AAHPERD). The design for this study was cross sectional. All data represent chairpersons' reports on a single survey instrument.
Synergy Between Leptin Therapy and a Seemingly Negligible Amount of Voluntary Wheel Running Prevents Progression of Dietary Obesity in Leptin-Resistant Rats
Authors: Shapiro Alexandra , Matheny Michael , Zhang Yi , Tümer Nihal , Cheng Kit-Yan , Rogrigues Enda , Zolotukhin Sergei , Scarpace Philip J.
Published: December 2007

OBJECTIVE—We examined whether chronic leptin treatment of diet-induced obese rats promotes or alleviates the susceptibility to continued high-fat feeding. Second, we examined if voluntary wheel running is beneficial in reducing the trajectory of weight gain in high-fat–raised leptin-resistant rats.

RESEARCH DESIGN AND METHODS—Sprague-Dawley rats were fed a standard diet or a high-fat diet for 5 months, and then hypothalamic leptin overexpression was induced through central administration of adeno-associated virus–encoding leptin while continuing either the standard or high-fat diet. Two weeks later, half of the rats in each group were provided access to running wheels for 38 days while being maintained on either a standard or high-fat diet.

RESULTS—In standard diet–raised rats, either wheel running or leptin reduced the trajectory of weight gain, and the combined effect of both treatments was additive. In high-fat–raised leptin-resistant rats, leptin overexpression first transiently reduced weight gain but then accelerated the weight gain twofold over controls. Wheel running in high-fat–raised rats was sixfold less than in standard diet–raised rats and did not affect weight gain. Surprisingly, wheel running plus leptin completely prevented weight gain. This synergy was associated with enhanced hypothalamic signal transducer and activator of transcription (STAT) 3 phosphorylation and suppressor of cytokine signaling 3 expression in wheel running plus leptin compared with leptin-treated sedentary high-fat counterparts. This enhanced STAT3 signaling associated with the combination treatment occurred only in high-fat–raised, leptin-resistant rats and not in standard diet–raised, leptin-responsive rats.

CONCLUSIONS—Chronic leptin treatment in diet-induced obese rats accelerates dietary obesity. However, leptin combined with wheel running prevents further dietary weight gain. Thus, this combination therapy may be a viable antiobesity treatment.
Estimation of uv Exposure in Croatia Over The Summer Using A Simple Approximate Formula
Authors: Pehnec Gordana , Kezele Nenad , Šorgo Glenda
Published: December 2007

Estimation of uv Exposure in Croatia Over The Summer Using A Simple Approximate Formula

The Tropospheric Ultraviolet-Visible (TUV) model, version 4.2 developed by Madronich (2003) was used to estimate the extent of ultraviolet (UV) exposure of general population in Croatia over the summer. Solar noon values (13 h local time, CEST) of the ultraviolet index (UVI) for the period April to October 2004 were calculated for 61 cities in Croatia. The results showed that the risk of sunburn at 13 h local time in clear weather was high between April and September (UVI > 7) and very high in July (UVI > 10). In July, the UVI exceeded 8 between 11 h and 15 h local time. In this study, we developed a simple approximate formula to estimate UVI. The formula includes data on the time, date, altitude and clouds. The difference between our estimate and the TUV model for the summer months of June, July and August at 10 h to 16 h local time was less than 10 %.
Nanotoxicology for Safe and Sustainable Nanotechnology
Authors: Drobne Damjana
Published: December 2007

Nanotoxicology for Safe and Sustainable Nanotechnology

Nanotechnology is the term given to those areas of science and engineering where the phenomena take place at nanoscale dimensions. Nanoparticles are particles with <100 nm in one dimension. They have different physical, chemical, electrical and optical properties than those that occur in bulk samples of the same material. Understanding these nanoscale properties and finding ways to engineer new nanomaterials will have a revolutionary impact, from more efficient energy generation and data storage to improved methods for diagnosing and treating diseases. Nanotechnology is poised to become a major factor in the world's economy and part of our everyday lives in the near future. Hundreds of tonnes of nanoparticles already enter the environment annually, but still very little is known of their interactions with biological systems. Recent studies indicate that some nanoparticles are not completely benign to biological and environmental targets. The challenge for toxicologists is to identify key factors that can be used to predict toxicity, permit targeted screening, and allow material scientists to generate new, safer nanoparticles with this structure-toxicity information in mind. The aim of this paper is to summarize some known facts about nanomaterials and discuss future perspectives, regulatory issues and tasks of the emerging branch of toxicology, that is, nanotoxicology.
Effects of Volcanic Eruptions on Environment and Health
Authors: Žuškin Eugenija , Mustajbegović Jadranka , Jelinić Jagoda , Pucarin-Cvetković Jasna , Milošević Milan
Published: December 2007

Učinci Vulkanskih Erupcija Na Okoliš I Zdravlje

Vulkani predstavljaju prijetnju za gotovo pola milijarde ljudi: danas je na Zemlji aktivno oko 500 vulkana, a svake se godine događa 10 do 40 njihovih erupcija. Posljedice erupcija vulkana odražavaju se na okoliš, utječu na klimu te na život i zdravlje ljudi, a vezani su uz pogoršanje socijalnih i gospodarskih uvjeta života. U okoliš s magmom uz vodenu paru (H2O), na površinu dospijevaju plinovi ugljikov dioksid (CO2) i sumporv dioksid (SO2), ugljikov monoksid (CO), vodikov sulfid (H2S), ugljikov sulfid (CS), ugljikov disulfid (CS2), klorovodik (HCl), vodik (H2), metan (CH4), fluorovodik (HF), bromovodik (HBr) i različiti organski spojevi te teški metali (živa, olovo, zlato). Njihovi nepovoljni učinci ovise o udaljenosti od vulkana te o eruptivnim obilježjima, tj. o viskozitetu magme i koncentraciji plinova. Štetnosti bliže vulkanu uključuju piroklastične rijeke, rijeke blata, plinova i vodene pare, potrese, zračne udare i tsunami. U štetnosti u udaljenim područjima ubrajaju se učinci toksičnosti vulkanskog pepela i zdravstveni problemi vezani uz dišni sustav, oči, kožu, zatim psihološke posljedice, ozljede, komunikacijski i transportni problemi, problem odlaganja otpada i opskrbe vodom, rušenje kuća, kao i pad strujnog napona. Dolazi do pogoršanja kvalitete vode i smanjenja kišnih razdoblja, oštećenja poljoprivrednih usjeva, uništavanja vegetacije. Za vrijeme vulkanskih erupcija i neposredno nakon njih povećan je morbiditet, posebno od respiratornih bolesti, a povećan je i mortalitet osoba zahvaćenih vulkanskom erupcijom. Nepovoljni zdravstveni učinci mogu se djelomično prevenirati pravodobnom primjenom zaštitnih mjera.
Potential Markers of Arterial and/or Venous Thromboses and their Complications in Primary Antiphospholipid Syndrome
Authors: Bećarević Mirjana , Majkić-Singh Nada
Published: December 2007

Potential Markers of Arterial and/or Venous Thromboses and their Complications in Primary Antiphospholipid Syndrome

Antiphospholipid syndrome is characterized by venous or arterial thromboses and/or recurrent abortions accompanied by antiphospholipid antibodies and it can be primary (PAPS) or secondary (SAPS) to another disease. Arterial thromboses are less common than venous and most frequently they manifest as ischemia or infarction. Venous thromboses are usually multiple and bilateral and the most common complication of venous thromboses are pulmonary emboli. Considering that laboratory diagnosis of PAPS is currently based on persistently positive aCL, aβ2gpl and/or LA tests, and that neither one of those tests can discriminate between PAPS patients with arterial or venous thromboses or their complications, the aim of this study was to investigate the diagnostical significance of the determination of apo(a), oxLDL, anti-oxLDL antibodies, antianxA5 antibodies, hsCRP, C3 and C4 complement components and HPT for discrimination between PAPS patients with diverse clinical manifestations. Considering that elevated oxLDL and anti-oxLDL antibodies concentrations were found in PAPS patients, and also in subgroups of PAPS patients with MI or PE, it can be concluded that those parameters represent additional risk factors which together with other factors may lead to thromboses and their complications in PAPS. Regarding the fact that C3 and C4 concentrations were decreased in PAPS patients and that a positive correlation was found between hsCRP and C3 concentrations, this finding could indicate potential roles of these parameters as markers of atherosclerosis, which represents the leading cause of morbidity and mortality. HPT and apo(a) concentrations are not independent risk factors for MI in PAPS because lower levels were found in those patients in comparison to MI survivors without PAPS. No significant correlation of anti-anxA5 antibodies and the presence of arterial or venous thromboses or their complications was found, but increased concentrations of the IgG isotype of those antibodies could be a marker for recurrent abortions in PAPS, although this finding should be further investigated on a larger number of patients with this clinical finding. Determination of hsCRP in PAPS patients could not be an adequate parameter which would provide discrimination between patients with increased risk for development and/or recurrence of venous and/or arterial thromboses, nor for their complications, because no statistically significant difference in concentrations of this parameter was found among PAPS, IM, PE and SLE patients who were included in this study.
The Importance of Free Light Chains of Immunoglobulins Determination in Serum
Authors: Čabarkapa Velibor , Stošić Zoran , Đerić Mirjana , Vučurević-Ristić Ljiljana , Drljača Mirjana
Published: December 2007

The Importance of Free Light Chains of Immunoglobulins Determination in Serum

For many years, Bence Jones proteinuria has been an important diagnostic marker for multiple myeloma. Relatively new serum tests for free kappa and free lambda light chains of immunoglobulins reflect the production of free light chains more accurately than urine tests. In this study, we examined the value of serum free light chains measurement in the diagnosis of some neoplastic diseases and the discrepance between the findings of serum protein electrophoresis and serum free light chains. Thirty one patients (f=19, m=12) were included in the study, most of them with blood malignant diseases. The results show that in six patients with normal gamma and beta electrophoresis fractions there are abnormal levels of free light chains and/or an abnormal κ/LD ratio. In 20 patients we found an abnormal κ/LD ratio, and in 21 patients we found an abnormal κ or LD level, or both. The obtained results show the important role of serum free light chains determination in identifying patients with monoclonal gammopathies.
Application of Random Amplified Polymorphic DNA Analysis in Identifying Phellinus Igniarius Strains
Authors: Du Ping , Chen Yan-Qiu , Li Chang-Tian , Li Yu
Published: December 2007

Application of Random Amplified Polymorphic DNA Analysis in Identifying Phellinus Igniarius Strains

Described in this paper, the random amplified polymorphic DNA (RAPD) analysis was conducted with 20 random primers in various strains of Phellinus igniarius collected from different localities. The results showed that 17 of the 20 random primers were polymorphic ones. The DNA bands derived from each primer amplifying in tested strains ranged from 10 to 33. The size of the amplified DNA fragments ranged from 250 to 2000 base pairs. Of each test primer, a wide variation in banding profiles was observed among the 7 strains of P. igniarius. A total of 377 band positions were scored for all of the tested strains, which differed significantly among the bands from different primers. UPGMA cluster analysis subdivided the tested strains into two groups, which was helpful to find out the difference among the tested strains and to distinguish them directly.
The Diagnostic Value of N-Acetyl-β-D-Glucosaminidase and Microalbumin Concentrations in Rheumatoid Arthritis
Authors: Spasovski Dejan , Gruev Todor , Marina Nada , Calovski Jordan , Percinkova Snežana , Osmani Baskim , Rajčevska Ljubinka , Cakalaroski Kočo , Sotirova Tatjana , Balkanov Svetlana , Slaninka-Micevska Maja
Published: December 2007

The Diagnostic Value of N-Acetyl-β-D-Glucosaminidase and Microalbumin Concentrations in Rheumatoid Arthritis

The purpose of this research was to compare the diagnostic values of laboratory variables, to present quantitative evaluations of the diagnostic sifted test with reference to sensitivity and specificity, the predictive value of the positive and negative test and precision of the test for N-acetyl-β-D-glucosa-minidase (NAG), microalbumin, rheumatoid factor (RF), Creactive protein (CRP), DAS 28 index, in early diagnosis of untreated rheumatoid arthritis (RA), and to define the effect of untreated rheumatoid arthritis on glomerular and tubular function. Using a colorimetric assay for the determination of Nacetyl-β-D-glucosaminidase and an immunoturbidimetric assay for the determination of urinary albumin, the samples of serum and urine have been examined in 70 participants (35 RA who were not treated, 35 healthy controls). RF was defined with the test for agglutination (Latex RF test) in the same participants. Out of 35 examined patients with RA, in 13 we found the presence of NAG enzymuria (sensitivity of the test 37.14%), while microalbuminuria appeared in 4 patients (sensitivity of the test 11.42%). RF appeared in 17 patients (sensitivity of the test 48.57%). Four patients were NAG and RF positive, while 3 patients were microalbuminuria and RF positive. Among 18 RF negative patients, 9 patients were NAG positive, and 1 patient presented with microalbuminuria. Among 17 RF positive RA, the presence of NAG was found in 4 patients, and the presence of microalbuminuria in 3 patients. Among 18 RF negative RA, NAG enzymuria appeared in 9 patients. Microalbuminuria was present in 1 patient. In the healthy control group, 8 patients were NAG positive, 2 patients were positive for microalbuminuria. RF appeared in 2 patients. NAG has higher sensitivity than microalbuminuria in the detection of asymptomatic renal lesions in untreated RA.
Skull base reconstruction in the extended endoscopic transsphenoidal approach for suprasellar lesions
Authors: Cavallo Luigi Maria , Messina Andrea , Esposito Felice , de Divitiis Oreste , Fabbro Mateus Dal , de Divitiis Enrico , Cappabianca Paolo
Published: December 2007

Object

The extended transsphenoidal approach to the suprasellar region has the advantages of minimal invasiveness and brain manipulation in the surgical treatment of small to medium lesions. At the same time, however, it carries a higher risk of postoperative cerebrospinal fluid (CSF) leakage and related complications than those for the standard transsphenoidal approach. Effective reconstruction of large skull base defects is a major concern in such extended approaches and remains challenging.

Methods

Between January 2004 and April 2006, 21 patients affected by different suprasellar lesions underwent the extended endoscopic endonasal transtuberculum-transplanum approach. Three different techniques were used for the skull base reconstructions. In all cases, dehydrated human pericardium (Tutoplast) for dural reconstruction and a copolymer of l-lactic acid and glycolic acid (LactoSorb) as a bone substitute were used. Collagen sponges, fibrin glue, and an inflated Foley balloon catheter were also used to fill the sphenoid sinus cavity.

Results

Two cases of postoperative CSF leaks (9.5%) and one case of mycotic sinusitis (4.8%) occurred following the intradural (inlay) and intraextradural (inlay-overlay) graft positioning. No cases of postoperative CSF leakage occurred in cases in which the extradural-only reconstruction procedure was applied. No meningitis or other complications related to the closure were noticed.

Conclusions

The rate of postoperative CSF leakage after an extended approach to the suprasellar area is higher compared with that following standard pituitary surgery. Reconstruction after craniopharyngioma surgery exposes patients to an increased risk of postoperative CSF leaks. The extradural (overlay) technique was found to be the most effective in assuring a watertight closure.
Irradiation of cochlear structures during vestibular schwannoma radiosurgery and associated hearing outcome
Authors: Massager Nicolas , Nissim Ouzi , Delbrouck Carine , Delpierre Isabelle , Devriendt Daniel , Desmedt Françoise , Wikler David , Brotchi Jacques , Levivier Marc
Published: December 2007

Object

The purpose of this study was to measure the dose of radiation delivered to the cochlea during a Gamma knife surgery (GKS) procedure for treatment of patients with vestibular schwannomas (VSs), and to analyze the relationship between cochlear irradiation and the hearing outcome of these patients.

Methods

Eighty-two patients with VSs were treated with GKS using a marginal dose of 12 Gy. No patient had neurofibromatosis Type 2 disease, and all had a Gardner–Robertson hearing class of I to IV before treatment, and a radiological and audiological follow-up of at least 1-year after GKS. The dosimetric data of the volume of the cochlea were retrospectively analyzed and were correlated with the auditory outcome of patients.

Results

The mean radiation dose delivered to the cochlear volume ranged from 1.30 to 10.00 Gy (median 4.15 Gy). The cochlea received significantly higher radiation doses in patients with worsening of hearing after GKS. A highly significant association between the cochlear and the intracanalicular dose of radiation delivered during GKS was found.

Conclusions

During GKS for VSs, relatively high doses of radiation can be delivered to the cochlea. Worsening of hearing after GKS can be the consequence of either radiation injury to the cochlea or the irradiation dose delivered into the auditory canal, or both.
Gamma Knife surgery for skull base chordomas and chondrosarcomas
Authors: Hasegawa Toshinori , Ishii Dai , Kida Yoshihisa , Yoshimoto Masayuki , Koike Joji , Iizuka Hiroshi
Published: December 2007

Object

The purpose of this study was to evaluate radiosurgical outcomes in skull base chordomas and chondrosarcomas, and to determine which tumors are appropriate for stereotactic radiosurgery as adjuvant therapy following maximum tumor resection.

Methods

Thirty-seven patients (48 lesions) were treated using Gamma Knife surgery (GKS); 27 had chordomas, seven had chondrosarcomas, and three had radiologically diagnosed chordomas. The mean tumor volume was 20 ml, and the mean maximum and marginal doses were 28 and 14 Gy, respectively. The mean follow-up period was 97 months from diagnosis and 59 months from GKS.

Results

The actuarial 5- and 10-year survival rates after GKS were 80 and 53%, respectively. The actuarial 5- and 10-year local tumor control (LTC) rates after single or multiple GKS sessions were 76 and 67%, respectively. All patients with low-grade chondrosarcomas achieved good LTC. A tumor volume of less than 20 ml significantly affected the high rate of LTC (p = 0.0182). No patient had adverse radiation effects, other than one in whom facial numbness worsened despite successful tumor control.

Conclusions

As an adjuvant treatment after resection, GKS is a reasonable option for selected patients harboring skull base chordomas or chondrosarcomas with a residual tumor volume of less than 20 ml. Dose planning with a generous treatment volume to avoid marginal treatment failure should be made at a marginal dose of at least 15 Gy to achieve long-term tumor control.
Prediction of meningioma consistency using fractional anisotropy value measured by magnetic resonance imaging
Authors: Kashimura Hiroshi , Inoue Takashi , Ogasawara Kuniaki , Arai Hiroshi , Otawara Yasunari , Kanbara Yoshiyuki , Ogawa Akira
Published: December 2007

Object

Preoperative planning for meningiomas requires information about tumor consistency as well as location and size. In the present study the authors aimed to determine whether the fractional anisotropy (FA) value calculated on the basis of preoperative magnetic resonance (MR) diffusion tensor (DT) imaging could predict meningioma consistency.

Methods

In 29 patients with intracranial meningiomas, MR DT imaging was performed preoperatively, and the FA values of the tumors were calculated. Tumor consistency was intraoperatively determined as hard or soft, and the histological diagnosis of the tumor was established.

Results

Of the 29 tumors, 11 were classified as hard and 18 as soft. The FA values of fibroblastic meningiomas were significantly higher than those of meningothelial meningiomas (p = 0.002). The FA values of hard tumors were significantly higher than those of soft tumors (p = 0.0003). Logistic regression analysis demonstrated that the FA value was a significant independent predictor of tumor consistency (p = 0.007).

Conclusions

The FA value calculated from preoperative MR DT imaging predicts meningioma consistency.
Alpha-II spectrin breakdown products in aneurysmal subarachnoid hemorrhage: a novel biomarker of proteolytic injury
Authors: Lewis Stephen B. , Velat Gregory J. , Miralia Lynn , Papa Linda , Aikman Jada M. , Wolper Regina A. , Firment Chris S. , Liu Ming Chen , Pineda Jose A. , Wang Kevin K. W. , Hayes Ronald L.
Published: December 2007

Object

Aneurysmal subarachnoid hemorrhage (ASAH) is a serious event with grave consequences. Delayed ischemic neurological deficits caused by cerebral arterial vasospasm contribute significantly to death and disability. Biomarkers may reflect brain injury and provide an early warning of impending neurological decline and stroke from ASAH-induced vasospasm. Alpha-II spectrin is a cytoskeletal protein whose breakdown products are candidate surrogate markers of injury magnitude, treatment efficacy, and outcome. In addition, αII spectrin breakdown products (SBDPs) can provide information on the proteolytic mechanisms of injury.

Methods

Twenty patients who received a diagnosis of Fisher Grade 3 ASAH were enrolled in this study to examine the clinical utility of SBDPs in the detection of cerebral vasospasm in patients with ASAH. All patients underwent placement of a ventriculostomy for continual cerebrospinal fluid drainage within 72 hours of ASAH onset. Cerebrospinal fluid samples were collected every 6 hours and analyzed using Western Blotting for SBDPs. Onset of vasospasm was defined as an acute onset of a focal neurological deficit or a change in Glasgow Coma Scale score of two or more points. All suspected cases of vasospasm were confirmed on imaging studies.

Results

Both calpain- and caspase-mediated SBDP levels are significantly increased in patients suffering ASAH. The concentration of SBDPs was found to increase significantly over baseline level up to 12 hours before the onset of cerebral arterial vasospasm.

Conclusions

Differential expression of SBDPs suggests oncotic necrotic proteolysis may be predominant in acute brain injury after ASAH and cerebral arterial vasospasm.
Moving toward the petroclival region: a model for quantitative and anatomical analysis of tumor shift
Authors: Safavi-Abbasi Sam , Zabramski Joseph M. , Deshmukh Pushpa , Reis Cassius V. , Bambakidis Nicholas C. , Theodore Nicholas , Crawford Neil R. , Spetzler Robert F. , Preul Mark C.
Published: December 2007

Object

The authors quantitatively assessed the effects of balloon inflation as a model of tumor compression on the brainstem, cranial nerves, and clivus by measuring the working area, angle of attack, and brain shift associated with the retrosigmoid approach.

Methods

Six silicone-injected cadaveric heads were dissected bilaterally via the retrosigmoid approach. Quantitative data were generated, including key anatomical points on the skull base and brainstem. All parameters were measured before and after inflation of a balloon catheter (inflation volume 4.8 ml, diameter 20 mm) intended to mimic tumor compression.

Results

Balloon inflation significantly shifted (p < 0.001) the brainstem and cranial nerve foramina (mean [± standard deviation] displacement of upper brainstem, 10.2 ± 3.7 mm; trigeminal nerve exit, 6.99 ± 2.38 mm; facial nerve exit, 9.52 ± 4.13 mm; and lower brainstem, 13.63 ± 8.45 mm). The area of exposure at the petroclivus was significantly greater with balloon inflation than without (change, 316.26 ± 166.75 mm2; p < 0.0001). Before and after balloon inflation, there was no significant difference in the angles of attack at the origin of the trigeminal nerve (p > 0.5).

Conclusions

This study adds an experimental component to the emerging field of quantitative neurosurgical anatomy. Balloon inflation can be used to model the effects of a mass lesion. The tumor simulation created “natural” retraction and an opening toward the upper clivus. The findings may be helpful in selecting a surgical approach to increase the working space for resection of certain extraaxial tumors.
A computed tomography scan and anatomical cadaveric study of the pterygopalatine ganglion for use in Gamma Knife treatment of cluster headache
Authors: Alvernia Jorge E. , Spomar Daniel G. , Olivero William C.
Published: December 2007

Object

Gamma Knife surgery has recently been used to treat patients with cluster headaches. Both the trigeminal nerve root and the pterygopalatine ganglion (PPG) have been targeted. However, there are no clear-cut anatomical landmarks on computed tomography (CT) scans or magnetic resonance images that accurately identify the PPG. Therefore, the authors performed microsurgical dissections on latex-injected cadaver heads to expose the PPG and correlated the findings with thin-slice axial CT scans obtained in the same heads to determine how best to target the PPG.

Methods

Three cadaver heads (five sides) previously injected with colored latex were dissected using skull base approaches and microsurgical techniques to identify the PPG and surrounding structures. Measurements were then made to different osseous anatomical landmarks such as the foramen rotundum, vidian canal, and so on. The PPG was marked with a radiopaque marker and thin-slice CT scans were obtained in the cadaver heads to develop some correlates that could be used to identify where the PPG is located on CT scans.

Results

The PPG was clearly identified in all specimens and had a mean diameter of 3.58 ± 0.6 mm. The PPG was always located in the same plane (lateral and vertical) as the vidian canal and was located on average 2.7 ± 0.3 mm from the end of the canal. The vidian canal was clearly identified on coronal CT scans and had a diameter of 3.05 mm.

Conclusions

There was a clear and constant relationship between the PPG and vidian canal. The vidian canal is easily identified on coronal CT scans and can be used as a landmark to target the PPG with the Gamma Knife.