bluuebunny/crossref_metadata_2025 huggingface dataset:
Interleukin‐6 receptor gene polymorphisms and periodontitis in a non‐smoking Japanese population
Authors: Galicia Johnah C. , Tai Hideaki , Komatsu Yasutaka , Shimada Yasuko , Ikezawa Ikuyo , Yoshie Hiromasa
Published: August 2006

Aim: The indispensable role of interleukin‐6 receptor (IL‐6R) in regulating IL‐6 responses has been clearly established. We have previously reported that IL6R polymorphisms strongly influenced the serum levels of soluble IL‐6R. In this study, we investigated the association between these genetic variations and periodontitis.

Material and Methods: Among the seven novel IL6R single‐nucleotide polymorphisms (SNPs) reported, we genotyped two important sites: the +48892 A/C in exon 9 and the −183 G/A in the promoter region. The SNP in exon 9 results in Asp→Ala substitution in the proteolytic cleavage site of IL‐6Rα. In total, 212 periodontitis cases and 210 healthy controls were genotyped using polymerase chain reaction, restriction fragment length polymorphisms and direct sequencing methods.

Results: Analysis of the genotype distribution of the +48892 A/C SNP in periodontitis patients and in controls revealed a suggestive association with aggressive (p=0.04) and chronic periodontitis (p=0.04). In addition, the carriage rate for the A allele was significantly higher in chronic periodontitis patients [p=0.02, odds ratio (OR)=2.25]. No association was found in the −183 G/A SNP. The two markers were in linkage disequilibrium (LD) (|D′|=0.53).

Conclusion: The IL6R+48892 A/C polymorphism could act as a risk factor for periodontitis; however, further association and biological studies are needed.
Genetic polymorphisms in the MMP‐1 and MMP‐3 gene may contribute to chronic periodontitis in a Brazilian population
Authors: Astolfi Claudia Maria , Shinohara André Luís , Da Silva Rodrigo Augusto , Santos Maria Cristina Leme Godoy , Line Sergio Roberto Peres , De Souza Ana Paula
Published: August 2006

Objectives:Matrix metalloproteinase‐1 and ‐3 (MMP‐1, MMP‐3) represent proteinases that degrade macromolecules of the extracellular matrix. These enzymes play a fundamental role during destruction of periodontal tissues. Genetic polymorphisms were characterized in the promoter region of the MMP‐1 and MMP‐3 genes. The aim of this study was to investigate the relationship between these genetic variations with chronic periodontitis in a Brazilian population.

Material and Methods:Non‐smoking subjects (n=114) exhibiting sites 5 mm clinical attachment loss were recruited for study. Control subjects (n=109) should not exhibit clinical signals of periodontitis. MMP‐1 (−1607 1G/2G, −519 A/G) and MMP‐3 (−1612 5A/6A) gene promoter polymorphisms were genotyped using PCR‐RFLP methods.

Results:Analysis of polymorphisms showed no differences in distribution of the −1607 1G/2G and −519 A/G variants in the MMP‐1 gene between the healthy and periodontitis group (p>0.05). However, the distribution of genotype frequencies of the −1612 5A/6A polymorphism in the MMP‐3 gene showed that the 5A/5A genotype was significantly more frequent in the periodontitis group (p=0.008). The same was not observed in the 5A/6A genotype once only one 5A allele is carried. We also observed a trend to increase the frequency of the MMP‐1/MMP‐3 haplotype (2G/5A) in the periodontitis group (p=0.08).

Conclusion:On the basis of the results, no significant association is found for the MMP‐1 polymorphisms with susceptibility of periodontitis, while the MMP‐3 gene polymorphism may contribute to periodontal tissue destruction during periodontitis in Brazilian subjects.
Anti‐irritants II: efficacy against cumulative irritation
Authors: Andersen Flemming , Hedegaard Kathryn , Petersen Thomas Kongstad , Bindslev‐Jensen Carsten , Fullerton Ann , Andersen Klaus Ejner
Published: August 2006

So‐called anti‐irritants (AI) are widely used in cosmetic formulations, with the aim of reducing irritation from substances in the formulation. It may also be claimed that they are ‘soothing’ and ‘healing’ ingredients. However, the proof for these claims is circumstantial. The dose–response effect of 4 alleged AI (nifedipine, (‐)‐α‐bisabolol, canola oil and glycerol) was studied on experimentally induced acute irritation in healthy volunteers, and only glycerol showed dose‐related response and effects potentially better than no treatment. The acute irritation model only allowed a small window of opportunity in which to demonstrate efficacy. Therefore, the effect of AI was studied in a cumulative irritation model by inducing irritant dermatitis with 10 min daily exposures for 5 + 4 days (no irritation on weekend) to 1% sodium lauryl sulfate on the right and 20% nonanoic acid on the left volar forearm. AI ointments were applied twice daily. Clinical scoring was performed daily, evaporimetry (Trans Epidermal Water Loss), hydration and colourimetry were measured at baseline (D0), in the middle and at the end of treatment. The glycerol ointment was the only treatment statistically better than both ‘no treatment’ and vehicle.
Materials and allergens within spectacle frames: a review
Authors: Walsh Glyn , Wilkinson S. Mark
Published: August 2006

The materials that have been reported as causing allergic contact dermatitis within spectacle frames are identified, and their most likely location on the frame is highlighted. The lack of any real control over spectacle frame quality and content is indicated to be a problem, as is the difficulty in determining the true source of many frames. Much of the information must be obtained from anonymous sources in the industry, historical ‘common knowledge’ of indeterminate source or reports of dermatological problems.
Skin sensitization potency of methyl methacrylate in the local lymph node assay: comparisons with guinea‐pig data and human experience
Authors: Betts Catherine J. , Dearman Rebecca J. , Heylings Jon R. , Kimber Ian , Basketter David A.
Published: August 2006

There is compelling evidence that contact allergens differ substantially (by 4 or 5 orders of magnitude) with respect to their inherent skin‐sensitizing potency. Relative potency can now be measured effectively using the mouse local lymph node assay (LLNA) and such data form the basis of risk assessment and risk management strategies. Such determinations also facilitate distinctions being drawn between the prevalence of skin sensitization to a particular contact allergen and inherent potency. The distinction is important because chemicals that are implicated as common causes of contact allergy are not necessarily potent sensitizers. One example is provided by nickel that is undoubtedly a common cause of allergic contact dermatitis, but is a comparatively weak sensitizer in predictive tests. In an attempt to explore other examples of contact allergens where there may exist a discrepancy between prevalence and potency, we describe here analyses conducted with methyl methacrylate (MMA). Results of LLNA studies have been interpreted in the context of historical clinical data on occupational allergic contact dermatitis associated with exposure to MMA.
Symptoms of immediate chlorhexidine hypersensitivity in patients with a positive prick test
Authors: Aalto‐Korte Kristiina , Mäkinen‐Kiljunen Soili
Published: August 2006

There are numerous reports of anaphylaxis from chlorhexidine in surgical operations and other medical procedures, usually due to its application to wounds or mucous membranes. We wanted to analyse the clinical data of patients with a positive chlorhexidine prick test and perform some additional testing. We studied the case records of the patients with a positive chlorhexidine prick test and performed an open application test and tests for specific IgE. We found 33 patients with a positive prick test. 10 of them had had severe symptoms from chlorhexidine, and 11 had had only mild local symptoms. The size of the prick test reaction was mainly in line with the strength of the severest symptoms. Small 3‐ to 4‐mm reactions were usually without obvious clinical relevance. Specific IgE could be demonstrated in 6 patients out of 14 tested by the ImmunoCAP™ method. Besides severe attacks, patients with a positive prick test often have milder local symptoms, such as exacerbation of dermatitis. Local symptoms from chlorhexidine‐containing products may precede severe attacks. We recommend a prick test to be performed routinely when symptoms during medical interventional procedures, e.g. local and general anaesthesia, are investigated.
The impact of exposure variables on the induction of skin sensitization
Authors: Basketter David A. , Jefferies Donna , Safford Bob J. , Gilmour Nicola J. , Jowsey Ian R. , Mcfadden John , Chansinghakul Wannisa , Duangdeeden Imelda , Kullavanijaya Preya
Published: August 2006

Whereas many investigations of the variables associated with the elicitation of allergic contact dermatitis have been undertaken, to the point where we can begin to predict the likelihood of elicitation occurring in a given situation, the same is not true for the induction of skin sensitization. Studies have demonstrated that increasing dose has an impact; in an experimental setting, a number of variables received attention some decades ago. However, in the work reported here, the relative importance of the frequency and the duration of exposure is highlighted. In an investigation using a human repeated insult patch test, it was demonstrated that reduction of the exposure duration from 48 hr to 5 min decreased the rate of sensitization to 1% p‐phenylenediamine (PPD) from 54% to 3%. However, in an extended clinical study, it was observed that infrequent but longer duration and higher concentration exposure to PPD was significantly less likely to induce sensitization compared to more frequent, short duration, and lower concentration exposure. Detailed statistical analysis of the results indicated that the most important factor driving the induction of skin sensitization was the number of exposures.
Self‐reported skin exposure – validation of questions by observation
Authors: Anveden Ingegärd , Lidén Carola , Alderling Magnus , Meding Birgitta
Published: August 2006

The aim of this study was to validate questions regarding skin exposure using observation. The study group consisted of 40 individuals in 5 different occupations: nurse in an intensive care unit, car mechanic, hairdresser, kitchen worker, and office worker. The participants completed a questionnaire before the start of a working day. The questionnaire covered total skin exposure times to water, foodstuffs, chemicals, and occlusive gloves and also covered the frequency of hand‐washing during a working day. Observers subsequently used a hand‐held computer to register the time and the frequency of each exposure. A strong correlation between self‐reports and observations was found for questions regarding exposure times to water, foodstuffs, and occlusive gloves and also a moderate correlation for questions regarding frequency of hand‐washing. The present observation method was insufficient for estimating total exposure times to chemicals as the true exposure time is influenced by, e.g. the use of contaminated protective gloves and the efficacy with which the chemicals were removed. The inter‐observer reliability showed a very strong correlation. We consider the questions regarding skin exposure to water, foodstuffs, protective gloves, and hand‐washing to be useful for future studies. The observation method seems to be reliable, useful, and easy to apply.
Monitoring the spawning behaviour of chum salmon with an acceleration data logger
Authors: Tsuda Y. , Kawabe R. , Tanaka H. , Mitsunaga Y. , Hiraishi T. , Yamamoto K. , Nashimoto K.
Published: August 2006

Abstract –  The continuous observation of salmon behaviour in some wild environments can be extremely difficult. We recorded spawning behaviour of female chum salmon (Oncorhynchus keta) in the field simultaneously using visual observation and fish‐borne data loggers with two‐axis accelerometer sensors. Using only acceleration records, behaviours were successfully classified into the eight well‐known components of spawning behaviour: swimming, nosing, exploratory digging, nest digging, probing, oviposition, covering and post‐spawning digging. To understand how the female chum salmon modulates spawning behaviours in relation to changes in environmental conditions, we compared the behaviours of salmon during normal flow of clear water to those of salmon during the heavy flow of turbid water after a storm. Salmon in the normal flow showed all eight behaviours, whereas salmon in the heavy flow showed only three behaviours: swimming, nosing and exploratory digging. The proportion of time spent on swimming was greater in the heavy flow than in the normal flow (mean of 98.47% vs. 92.84%). Moreover, the proportion of tail beating in swimming was greater in the heavy flow (77.86%) than in the normal flow (15.63%). Our results indicate that the behaviour of female chum salmon was strongly affected by the heavy flow of turbid water after a storm. The recording of accelerations is a promising method for clarifying the spawning behaviour of salmonids in the wild where continuous visual observation is too difficult.
Whole‐lake influences of littoral structural complexity and prey body morphology on fish predator–prey interactions
Authors: Sass G. G. , Gille C. M. , Hinke J. T. , Kitchell J. F.
Published: August 2006

Abstract –  We used a longline tethering method to examine the relationship between prey refugia, prey body morphology and the location and magnitude of predation mortality within an individual lake and among three lakes that differed in coarse woody habitat (CWH) and aquatic macrophyte abundances. Predation events were lowest in the macrophyte and/or CWH refuges, peaked at or just beyond the refuge edge and declined in pelagic portions of the lakes. Predation risk at the refuge edge and just beyond was positively correlated with the abundance of littoral refuge. In contrast, predation events within the refuge and in the pelagic zone were negatively correlated with littoral refuge abundance. Deep‐bodied and spiny prey morphologies were less vulnerable to predation than fusiform prey lacking fin spines. The structural complexity of littoral zones and prey fish body morphology may influence the outcome of predator–prey interactions and ultimately determine fish species assemblages in lakes.
Long‐term changes in the smolt size and age of Atlantic salmon, Salmo salar L., in a northern Baltic river related to parr density, growth opportunity and postsmolt survival
Authors: Jutila E. , Jokikokko E. , Julkunen M.
Published: August 2006

Abstract –  The size of wild Atlantic salmon (Salmo salar L.) smolts in 1972–2004 was studied in relation to parr density, smolt age, growth opportunity and postsmolt survival in the Simojoki River. There was a significant negative regression between the annual mean smolt size and the density of wild >1 year parr in the previous autumn, but not between the annual mean smolt size and age. The density of reared parr released into the river or the growth opportunity, based on the day length and air temperature during the previous summer, did not affect the size of wild smolts. The data on postsmolt survival based on recaptures of Carlin‐tagged smolts showed a significant positive relationship (P < 0.01) between the survival of postsmolts and the annual size of wild smolts. It is hypothesised that the increased density of wild >1 year parr could have contributed to the decreased smolt size since the 1990s, and the reduced size of wild smolts could be included among the factors resulting in their declined postsmolt survival in the Baltic Sea.
Ontogenetic diet profiles and size‐dependent diet partitioning of ruffe Gymnocephalus cernuus, perch Perca fluviatilis and pumpkinseed Lepomis gibbosus in Lake Balaton
Authors: Rezsu E. , Specziár A.
Published: August 2006

Abstract –  Life‐long diet ontogeny and size‐dependent intra‐ and interspecific diet partitioning of the native ruffe and perch and the introduced pumpkinseed, were studied in Lake Balaton. Estimated intraspecific diet overlap was high in ruffe, whereas in perch and pumpkinseed only the neighbouring size groups exhibited a high diet similarity. Interspecific diet overlap among size groups of the three species was moderate and ≥60% diet overlap occurred only in 13 size group pair variations out of the 429 analysed. The earliest developmental stages of the three species were planktivorous, whereas larger ruffe and some size groups of perch and pumpkinseed fed dominantly on chironomids. Adult perch and pumpkinseed consumed different littoral macroinvertebrates, while the largest perch were piscivorous. Although productivities of the two studied areas differ significantly, this had only little effect on the diet ontogeny and diet partitioning of the three species. Present results suggest that in Lake Balaton these three species effectively partition food resources throughout their life span.
Locally aggressive central odontogenic fibroma associated to an inflammatory cyst: a clinical, histological and immunohistochemical study
Authors: Cercadillo‐Ibarguren Iñaki , Berini‐Aytés Leonardo , Marco‐Molina Vicente , Gay‐Escoda Cosme
Published: August 2006

The case describes a 38‐year‐old woman presenting a multilocular radiolucency affecting the entire right half of the lower jaw, with an unerupted third molar displaced to the region of the coronoid process. The histological study showed the presence of fibroblasts, focally with pleomorphic nuclei, dense collagen and an odontogenic epithelium with dystrophic calcifications. A cyst with an important inflammatory infiltrate was, moreover, observed.
Extraosseous schwannoma of the mental nerve clinically simulating intraosseous
Authors: Kowatsch E. , Feichtinger M. , Zemann W. , Karpf E. , Kärcher H.
Published: August 2006

We report a case of a benign neurilemmoma arising from the right mental nerve. Schwannomas are rare neurogenic tumours that originate from Schwann cells of the peripheral nervous system. Frequent locations are the head and neck region. Most of the tumours occur in the soft tissue whereas intraosseous schwannomas are rare. This case report deals with a young patient who was referred to our hospital with an unidentified fast‐growing tumour located mainly in the premolar region of the right mandible. The tumour presented as an expansive, unilocular, well defined, radiolucent lesion on orthopantomography. No expansion of the mandibular canal could be seen. Computerized tomography scans of the mandible helped to identify the solid nature of the tumour. A biopsy was necessary to make the final diagnosis and the tumour was then excised surgically. Postoperative magnetic resonance imaging scans and a histological examination of the surgical specimen showed no signs of neurofibromatosis type 2.
The efficacy of topical hyaluronic acid in the management of recurrent aphthous ulceration
Authors: Nolan A. , Baillie C. , Badminton J. , Rudralingham M. , Seymour R. A.
Published: August 2006

Background:  The aim of this study was to evaluate the efficacy of a topical hyaluronic acid (HA) preparation (0.2%) in the management of recurrent aphthous ulceration (RAU).

Methods:  One hundred and twenty patients with RAU participated in a randomized, placebo controlled, double‐blind trial to evaluate the efficacy of the topical HA and preparation. Outcome measures include soreness relief on immediate application (recorded over 60 min). Thereafter, patients completed a log diary recording soreness from the ulcers, occurrence of new ulcers and ulcer duration.

Results:  Both topical HA and placebo resulted in a significant reduction in ulcer soreness following immediate application (P = 0.0004). Throughout the rest of the investigation period, there was no significant differences (P > 0.05) between the treatments for reducing soreness. Patients treated with topical HA recorded few ulcers on day 5 of the investigation than those treated with placebo (P < 0.001). Likewise, the occurrence of new ulcers was lower in the HA treated group on day 4 when compared with placebo (P = 0.047).

Conclusion:  Topical HA (0.2%) may be of benefit in the management of RAU. Immediate reduction of symptoms appears to be a barrier effect.
Causative or precipitating aspects of burning mouth syndrome: a case–control study
Authors: Sardella Andrea , Lodi Giovanni , Demarosi Federica , Uglietti Daniela , Carrassi Antonio
Published: August 2006

Background:  On causative or precipitating causes of burning mouth syndrome (BMS), there is a lack of consensus. In this prospective case–control study, we compared clinical features and laboratory aspects to evaluate the association of the proposed causative/precipitating factors of BMS.

Methods:  A total of 61 BMS patients and 54 control subjects underwent several evaluations: rest and stimulated salivary flow rates measurements, laboratory tests, isolation of Candida species, assessment of parafunctional activities, detection of anxiety and depression by means of the Hospital Anxiety and Depression Scale. Odds ratio and 95% confidence interval were calculated to compare the variables.

Results:  No statistically significant differences were found with regard to the tested variables except for anxiety and depression.

Conclusions:  The results of this study seem not to support a role for the usually reported causative or precipitating factors of BMS and efforts should be addressed towards different aetiologies including possible neuropathic mechanisms of BMS.
Establishment and characterization of a spindle cell squamous carcinoma cell line
Authors: Kudo Yasusei , Ogawa Ikuko , Kitagawa Masae , Kitajima Shojiro , Samadarani Siriwardena B. S. M. , Aobara Noriko , Matsuda Chika , Miyauchi Mutsumi , Takata Takashi
Published: August 2006

Background:  Spindle cell squamous carcinoma (SCSC) is a rare and peculiar biphasic malignant neoplasm that occurs mainly in the upper aerodigestive tract. It consists of sarcomatoid proliferation of pleomorphic spindle‐shaped cells and squamous cell carcinoma.

Methods:  Here, we established a SCSC cell line from a tumour arisen in gingiva. We characterized the feature of a SCSC cell line by immunohistochemistry. To know the biological feature, we examined the cell growth, invasiveness and epithelial‐mesenchymal transition markers of a SCSC cell line in comparison with oral squamous cell carcinoma (OSCC) cell lines.

Results:  By immunohistochemical analyses, the primary tumour expressed cytokeratin and vimentin, indicating carcinosarcoma‐like characters. This tumour also showed overexpression of p53 protein. Cultured SCSC cells resulted in bypass of crisis and maintenance over passage 100. The established SCSC cell line was spindle‐shaped and showed identical immunohistochemical characters to those of primary tumour cells. Similar to the primary tumour, the cell line showed p53 overexpression and had p53 mutation at codon 132: AAG (lys)→AAT (asp). The SCSC cell line grew slower than two other OSCC cell lines (MSCC‐1 and HSC‐2), whereas SCSC cells had remarkable invasiveness in comparison with these cell lines. Moreover, SCSC cells expressed wnt‐5a and vimentin mRNA at high levels, but did not express E‐cadherin mRNA. This expression pattern of the markers was similar to that of mesenchymal cells, not of epithelial cells.

Conclusion:  In the present study, we newly established a SCSC cell line with strong invasiveness. This is the first report on the establishment of SCSC cell line. The SCSC cell line can be a useful cell model for the study to know the cytodifferentiation and nature of SCSC.
Range and demographics of odontogenic cysts diagnosed in a UK population over a 30‐year period
Authors: Jones A. V. , Craig G. T. , Franklin C. D.
Published: August 2006

Background:  The aim of this study was to determine the range of all histologically diagnosed odontogenic cysts along with age range, sex distribution and site of presentation over a 30‐year period.

Methods:  All entries for odontogenic cysts occurring during 1975–2004 inclusive were retrieved and analysed for demographic data.

Results:  A total of 55 446 specimens were received, of these 7121 (12.8%) specimens were diagnosed as odontogenic cysts. Radicular cyst was the most common diagnosis (52.3%), followed by dentigerous cyst (18.1) and odontogenic keratocysts (11.6%).

Conclusions:  Our study provides demographic data on a large series of odontogenic cysts in a European population. This is one of the largest series reported to date. Cysts such as the paradental cyst have a predilection for certain ages, sexes and sites. Odontogenic keratocysts and glandular odontogenic cysts have a marked propensity to recur as well as behave aggressively. It is essential that such lesions are detected as early as possible to minimize any necessary surgery.
Impaired postnatal development of hippocampal dentate gyrus in Sp4 null mutant mice
Authors: Zhou X. , Qyang Y. , Kelsoe J. R. , Masliah E. , Geyer M. A.
Published: August 2006

Sp4, a member of the Sp1 family of transcription factors, is expressed restrictively in the developing nervous system and abundantly in the hippocampus. Previously, we demonstrated that hypomorphic Sp4 mice display hippocampal vacuolization and concomitant deficits in memory and sensorimotor gating. Here, we report further analyses of Sp4 functions during postnatal development of the dentate gyrus in Sp4 null mutant mice. A reduced cell proliferation restrictively in hippocampus, but not cerebellum, was observed in the first week of postnatal development of Sp4 null mutant mice. The dendritic growth and arborization of dentate granule cells was decreased in hippocampal cultures in vitro from mutant neonatal mice. The adult Sp4 null mutant mice displayed decreased dentate granule cell density with reduced width of both dentate gyrus and the molecular layer. The abnormality of the molecular layer was indicated by a reduced level of synaptophysin expression in the mutant mice. The Sp4 transcription factor therefore appears to predominantly regulate the development of dentate granule cells.
Increased response to morphine in mice lacking protein kinase C epsilon
Authors: Newton P. M. , Kim J. A. , McGeehan A. J. , Paredes J. P. , Chu K. , Wallace M. J. , Roberts A. J. , Hodge C. W. , Messing R. O.
Published: August 2006

The protein kinase C (PKC) family of serine–threonine kinases has been implicated in behavioral responses to opiates, but little is known about the individual PKC isozymes involved. Here, we show that mice lacking PKCɛ have increased sensitivity to the rewarding effects of morphine, revealed as the expression of place preference and intravenous self‐administration at very low doses of morphine that do not evoke place preference or self‐administration in wild‐type mice. The PKCɛ null mice also show prolonged maintenance of morphine place preference in response to repeated testing when compared with wild‐type mice. The supraspinal analgesic effects of morphine are enhanced in PKCɛ null mice, and the development of tolerance to the spinal analgesic effects of morphine is delayed. The density of μ‐opioid receptors and their coupling to G‐proteins are normal. These studies identify PKCɛ as a key regulator of opiate sensitivity in mice.
A New Independently Derived Social Spider with Explosive Colony Proliferation and a Female Size Dimorphism1
Authors: Avilés Leticia , Maddison Wayne P. , Agnarsson Ingi
Published: August 2006

Permanent cooperative sociality is rare in spiders. Here we describe sociality in a cobweb (Theridiidae) genus with no other known social species. In five areas of eastern Ecuador, we found nests of Theridion nigroannulatum containing from a single to several thousand adults living together in a communal web. Spiders cooperated in prey capture and shared their food. Subadult to young adult sex ratios were highly female biased, suggesting a strongly subdivided population structure as in other permanent‐social spiders. Unusual aspects of T. nigroannulatum's biology include the existence of adult females of two discrete sizes, an extreme boom and bust pattern of colony growth, and the presence, within larger colonies, of populations of a predatory spider (Faiditus spp., Argyrodinae) that may play the role of a colony‐level parasite. The existence of females of two sizes may be the result of alternative female reproductive strategies, intracolony competition for resources, or an incipient caste system in this species. A redescription and phylogenetic analysis corroborate the placement of this species in Theridion, indicating that sociality has evolved independently in at least three theridiid genera.
THE DENSITY OF RATIONAL POINTS ON NON-SINGULAR HYPERSURFACES, II
Authors: BROWNING T. D. , HEATH-BROWN D. R. , Starr J. M.
Published: August 2006

For any integers $d,n \geq 2$, let $X \subset \mathbb{P}^{n}$ be a non-singular hypersurface of degree $d$ that is defined over the rational numbers. The main result in this paper is a proof that the number of rational points on $X$ which have height at most $B$ is $O(B^{n - 1 + \varepsilon})$, for any $\varepsilon > 0$. The implied constant in this estimate depends at most upon $d$, $\varepsilon$ and $n$.
LOCAL CHARACTERISTIC $p$ COMPLETIONS OF WEAK $BN$-PAIRS
Authors: PARKER CHRISTOPHER , ROWLEY PETER
Published: August 2006

This paper establishes recognition theorems for the finite Lie-type groups defined in odd characteristic $p$. The hypotheses of these theorems are couched in terms of certain local data in the form of an amalgam which is called a weak $BN$-pair of rank 2. The groups to be recognized are completions of these amalgams which satisfy the condition of being of local characteristic $p$ (a condition satisfied by the finite Lie-type groups defined in characteristic $p$). The results presented will find application in one of the ongoing revisions of the finite simple group classification.
CONGRUENCES FOR THE COEFFICIENTS OF WEAKLY HOLOMORPHIC MODULAR FORMS
Authors: TRENEER STEPHANIE
Published: August 2006

Recent works have used the theory of modular forms to establish linear congruences for the partition function and for traces of singular moduli. We show that this type of phenomenon is completely general, by finding similar congruences for the coefficients of any weakly holomorphic modular form on any congruence subgroup $\Gamma_0 (N)$. In particular, we give congruences for a wide class of partition functions and for traces of CM values of arbitrary modular functions on certain congruence subgroups of prime level.
HIGHER STRING TOPOLOGY ON GENERAL SPACES
Authors: HU PO
Published: August 2006

In this paper, I give a generalized analogue of the string topology results of Chas and Sullivan, and of Cohen and Jones. For a finite simplicial complex $X$ and $k \geq 1$, I construct a spectrum $Maps(S^k, X)^{S(X)}$, which is obtained by taking a generalization of the Spivak bundle on $X$ (which however is not a stable sphere bundle unless $X$ is a Poincaré space), pulling back to $Maps(S^k, X)$ and quotienting out the section at infinity. I show that the corresponding chain complex is naturally homotopy equivalent to an algebra over the $(k + 1)$-dimensional unframed little disk operad $\mathcal{C}_{k + 1}$. I also prove a conjecture of Kontsevich, which states that the Quillen cohomology of a based $\mathcal{C}_k$-algebra (in the category of chain complexes) is equivalent to a shift of its Hochschild cohomology, as well as prove that the operad $C_{\ast}\mathcal{C}_k$ is Koszul-dual to itself up to a shift in the derived category. This gives one a natural notion of (derived) Koszul dual $C_{\ast}\mathcal{C}_k$-algebras. I show that the cochain complex of $X$ and the chain complex of $\Omega^k X$ are Koszul dual to each other as $C_{\ast}\mathcal{C}_k$-algebras, and that the chain complex of $Maps(S^k, X)^{S(X)}$ is naturally equivalent to their (equivalent) Hochschild cohomology in the category of $C_{\ast}\mathcal{C}_k$-algebras.
ON THE LAPLACE EQUATION WITH NON-LINEAR DYNAMICAL BOUNDARY CONDITIONS
Authors: VITILLARO ENZO
Published: August 2006

The main part of the paper deals with local existence and global existence versus blow-up for solutions of the Laplace equation in bounded domains with a non-linear dynamical boundary condition. More precisely, we study the problem consisting in: (1) the Laplace equation in $(0, \infty) \times \Omega$; (2) a homogeneous Dirichlet condition $(0, \infty) \times \Gamma_0$; (3) the dynamical boundary condition $ \frac {\partial u}{\partial \nu} = - |u_t|^{m-2} u_t + |u|^{p - 2} u$ on $(0, \infty) \times \Gamma_1$; (4) the initial condition $u(0, x) = u_0 (x)$ on $\partial \Omega$. Here $\Omega$ is a regular and bounded domain in $\mathbb{R}^n$, with $n \ge 1$, and $\Gamma_0$ and $\Gamma_1$ endow a measurable partition of $\partial \Omega$. Moreover, $m>1$, $2 \le p < r$, where $r = 2 (n - 1) / (n - 2)$ when $n \ge 3$, $r = \infty$ when $n = 1,2$, and $u_0 \in H^{1/2} (\partial \Omega)$, $u_0 = 0$ on $\Gamma_0$.

The final part of the paper deals with a refinement of a global non-existence result by Levine, Park and Serrin, which is applied to the previous problem.
KIRBY ELEMENTS AND QUANTUM INVARIANTS
Authors: VIRELIZIER ALEXIS
Published: August 2006

We define the notion of a Kirby element of a ribbon category $\mathcal{C}$ (not necessarily semisimple). Kirby elements lead to 3-manifold invariants. We characterize a class of Kirby elements, the algebraic Kirby elements, in terms of the structure maps of a Hopf algebra in $\mathcal{C}$. This class is sufficiently large to recover the quantum invariants of 3-manifolds of Reshetikhin and Turaev, of Hennings, Kauffman and Radford, and of Lyubashenko when these are well defined. The cases of a semisimple ribbon category and of a category of representations are explored in detail.
Analysis of Design Wave Loads on an FPSO Accounting for Abnormal Waves
Authors: Guedes Soares C. , Fonseca Nuno , Pascoal Ricardo , Clauss Guenther F. , Schmittner Christian E. , Hennig Janou
Published: August 2006

The paper presents an analysis of structural design wave loads on an FPSO. The vertical bending moment at midship induced by rogue waves are compared with rule values. The loads induced by deterministic rogue waves were both measured in a seakeeping tank and calculated by an advanced time domain method. Two procedures are used to calculate the expected extreme vertical bending moment during the operational lifetime of the ship. The first one relies on a standard linear long term prediction method, which results from the summation of short term distribution of maxima weighted by their probability of occurrence. The short term stationary seastates are represented by energy spectra and the ship responses by linear transfer functions. The second one is a generalization of the former and it accounts for the nonlinearity of the vertical bending moment, by using nonlinear transfer functions of the bending moment sagging peaks which depend of the wave height.
Nonlinear Analysis of Jacket-Type Offshore Platforms Using Fiber Elements
Authors: Asgarian B. , Aghakouchak A. A. , Bea R. G.
Published: August 2006

A nonlinear fiber element for analysis of jacket type offshore structures is formulated and implemented in the nonlinear program DRAIN-3DX. This element can be used for modeling the nonlinear behavior of both strut and portal members. The element predicts buckling load and post buckling behavior of strut members accurately. It also produces fairly accurate results for yield load and post yield behavior of portal members. This element is verified using the experimental data for individual strut and portal members subjected to cyclic displacements. The element is then used to predict nonlinear behavior of two tested X-braced jackets made of tubular members under cyclic lateral displacement. The results are in good agreement with experiments and the results of other analytical models in terms of frame hysteretic behavior, energy dissipation, buckling load, load-deformation curve, strength and stiffness degradation.
A Second Order Lagrangian Model for Irregular Ocean Waves
Authors: Fouques Sébastien , Krogstad Harald E. , Myrhaug Dag
Published: August 2006

Synthetic aperture radar (SAR) imaging of ocean waves involves both the geometry and the kinematics of the sea surface. However, the traditional linear wave theory fails to describe steep waves, which are likely to bring about specular reflection of the radar beam, and it may overestimate the surface fluid velocity that causes the so-called velocity bunching effect. Recently, the interest for a Lagrangian description of ocean gravity waves has increased. Such an approach considers the motion of individual labeled fluid particles and the free surface elevation is derived from the surface particles positions. The first order regular solution to the Lagrangian equations of motion for an inviscid and incompressible fluid is the so-called Gerstner wave. It shows realistic features such as sharper crests and broader troughs as the wave steepness increases. This paper proposes a second order irregular solution to these equations. The general features of the first and second order waves are described, and some statistical properties of various surface parameters such as the orbital velocity, slope, and mean curvature are studied.
Modeling Tidal Current Profiles by Means of Empirical Orthogonal Functions
Authors: Guedes Soares C. , Neves S. N.
Published: August 2006

The method of empirical orthogonal functions (EOFs) is used to model vertical velocity profiles of the current. The whole current field is decomposed into time series of along and cross-slope velocity components. These time series are then filtered keeping only the frequency bands corresponding to the most significant peaks of the current power density spectra, which in most cases correspond to the main semidiurnal and long period tidal components. New time series are originated containing only filtered current. For each one of these filtered time-series, EOFs and the respective principal components are then derived. The derivation of empirical orthogonal functions make possible the separation of the local flow variability into a few modes of variance. In a general way, the along-slope flow may be described mainly as barotropic, although the baroclinic contribution tends to reach some significance in the flow crossing the shelf slope.
Thermal and Flow Performance of a Microconvective Heat Sink With Three-Dimensional Constructal Channel Configuration
Authors: Moreno R. M. , Tao Y.-X.
Published: August 2006

The design, performance, manufacturing, and experimental validation of two convective heat sinks with scalable dimensions are presented. The heat sinks consist of an array of elemental units arranged in parallel. Each elemental unit is designed as a network of branching channels whose dimensions follow a group of geometric relations that have been derived from physiological fluid transport systems and the constructal method. The goal of these relations is to optimize both the point-to-point temperature difference within the heat sink and the pressure drop across the device under imposed geometric constraints. The first branching network is a generic three-dimensional (3-D) structure that was analyzed to push the limit of the heat sinks capability. The second is a heat sink that was designed specifically with the tape-casting fabrication method in mind. The heat sink has a branching network embedded within low temperature cofire ceramic (LTCC) and the same network embedded within thick film silver, which has the ability of being cofired with low temperature cofired ceramic substrates. The performance is evaluated using both a channel-level lumped model and a CFD model. The performance for different heat sink materials (low-temperature cofired ceramic and silver) is presented. The key results are then compared with the experimental results of the two scaled models. The results show good agreement within the experimental uncertainty. This validation confirms that the thermal performance and pumping efficiency of the constructal heat sink is superior compared to porous metal and conventional microchannel heat sinks under the same operating conditions, and that the designs are only limited by manufacturing techniques.
High Pressure Spray Cooling of a Moving Surface
Authors: Nasr G. G. , Sharief R. A. , Yule A. J.
Published: August 2006

A novel technique is described for investigating spray cooling of moving hot surfaces. An experimental investigation is described for vertically downwards water sprays impinging on a horizontal steel annulus of 250mm diameter with a surface temperature up to 600°C, and rotating at up to 120rpm, giving a tangential velocity of 1.35ms−1. The central homogeneous zones of sprays from full-cone atomizers are used at pressures up to 2.07MPa and the ranges of impacting spray parameters are 0.98to12.5kgm−2s−1 for mass flux, 49-230μm for volume median drop diameter, and 9.8-32.3ms−1 for impinging velocity (Yule, A. J., Sharief, R. A., and Nasr, G. G., 2000, “The Performance Characteristics of Solid Cone Spray Pressure Swirl Atomizers,” Ann. Tokyo Astron. Obs., 10(6), pp. 627–646). Time histories of the steel temperature, at positions within the annulus, are presented and analyzed to deduce the transient cooling as the instrumented section of the annulus was swept repeatedly under the spray. Discussion is provided on the physical processes occurring on the basis of the observations. Correlation equations derived to find relationships of surface heat flux with the spray and surface parameters provide further insight into these processes. The results confirm results for static surfaces, that droplet size is a relatively weak parameter, while droplet momentum flux and surface velocity are important. As the surface velocity is increased, peak heat transfer rate at the surface reduces, and its position moves downstream with respect to the spray centerline.
Studies on Gas-Solid Heat Transfer in Cyclone Heat
Exchanger
Authors: Jain A. , Mohanty B. , Pitchumani B. , Rajan K. S.
Published: August 2006

Cyclones can be used for heating solid particles where the direct contact with the gas is permitted. Since cyclones have potential applications as heat exchangers in fertilizer, polymer powder, pharmaceutical and other industries, study of cyclone as heat exchanger is deemed important. Experiments on air-solid heat transfer were carried out in a cyclone heat exchanger of 100mm inside diameter, using sand. The effects of solid feed rate (0.5-7.5g∕s), cyclone inlet air velocity (9-22m∕s), and four average particle sizes (163-460μm) on the heat transfer rate, exit solid temperature, and heat transfer coefficient have been studied. An empirical correlation has been proposed for the prediction of heat transfer coefficients based on the present experimental data. The proposed correlation predicts the heat transfer coefficients with an error of +10%to−15% for the present data and within an error of +25%to−15% for the data of other investigators.
Numerical Study of the Heat Transfer Rate in a Helical Static Mixer
Authors: Rahmani Ramin K. , Keith Theo G. , Ayasoufi Anahita
Published: August 2006

In chemical processing industries, heating, cooling, and other thermal processing of viscous fluids are an integral part of the unit operations. Static mixers are often used in continuous mixing, heat transfer, and chemical reactions applications. In spite of widespread usage, the flow physics of static mixers is not fully understood. For a given application, besides experimentation, the modern approach to resolve this is to use powerful computational fluid dynamics tools to study static mixer performance. This paper extends a previous study by the authors on an industrial helical static mixer and investigates heat transfer and mixing mechanisms within a helical static mixer. A three-dimensional finite volume simulation is used to study the performance of the mixer under both laminar and turbulent flow conditions. The turbulent flow cases were solved using k−ω model. The effects of different flow conditions on the performance of the mixer are studied. Also, the effects of different thermal boundary conditions on the heat transfer rate in static mixer are studied. Heat transfer rates for a flow in a pipe containing no mixer are compared to that with a helical static mixer.
Heat Transfer Analysis in Metal Foams With Low-Conductivity Fluids
Authors: Dukhan Nihad , Picón-Feliciano Rubén , Álvarez-Hernández Ángel R.
Published: August 2006

The use of open-cell metal foam in contemporary technologies is increasing rapidly. Certain simplifying assumptions for the combined conduction∕convection heat transfer analysis in metal foam have not been exploited. Solving the complete, and coupled, fluid flow and heat transfer governing equations numerically is time consuming. A simplified analytical model for the heat transfer in open-cell metal foam cooled by a low-conductivity fluid is presented. The model assumes local thermal equilibrium between the solid and fluid phases in the foam, and neglects the conduction in the fluid. The local thermal equilibrium assumption is supported by previous studies performed by other workers. The velocity profile in the foam is taken as non-Darcean slug flow. An approximate solution for the temperature profile in the foam is obtained using a similarity transform. The solution for the temperature profile is represented by the error function, which decays in what looks like an exponential fashion as the distance from the heat base increases. The model along with the simplifying assumptions were verified by direct experiment using air and several aluminum foam samples heated from below, for a range of Reynolds numbers and pore densities. The foam samples were either 5.08- or 20.32‐cm-thick in the flow direction. Reasonably good agreement was found between the analytical and the experimental results for a considerable range of Reynolds numbers, with the agreement being generally better for higher Reynolds numbers, and for foam with higher surface area density.
Drag
and Heat Transfer Reduction Phenomena of Drag-Reducing Surfactant Solutions in Straight and Helical
Pipes
Authors: Aly Wael I.
A. , Inaba Hideo , Haruki Naoto , Horibe Akihiko
Published: August 2006

Flow drag and heat transfer reduction phenomena of non-ionic aqueous surfactant solutions flowing in helical and straight pipes have been experimentally investigated at surfactant solution concentration range of 250-5000ppm and temperature range of 5-20°C. The helically coiled pipes have curvature ratios range of 0.018–0.045. Experimental findings indicate that the friction factors and the heat transfer coefficients of the surfactant solution in helical pipes are significantly higher than in a straight pipe and lower than Newtonian fluid flow like water through the same coils in the turbulent drag reduction region. Drag reduction and heat transfer reduction increase with an increase in surfactant solution concentration and temperature in the measured concentration and temperature ranges. On the other hand, they decrease with increasing of the curvature ratio. A set of empirical expressions for predicting the friction factor and the average Nusselt number for the surfactant solution’s flow through helical and straight pipes have been regressed based on the obtained data in the present experiments.