bluuebunny/crossref_metadata_2025 huggingface dataset:
Knops blood group haplotypes among distinct Brazilian populations
Authors: Covas Dimas Tadeu , De Oliveira Fabíola Singaretti , Rodrigues Evandra Strazza , Abe‐Sandes Kiyoko , Silva Wilson Araújo , Fontes Aparecida Maria
Published: December 2006

BACKGROUND: The Knops blood group system consists of antigens encoded by exon 29 of complement receptor 1 (CR1) gene. To better elucidate the complexity of Knops group system, the frequency of six single‐nucleotide polymorphisms (SNPs) in three Brazilian populations is determined.

STUDY DESIGN AND METHODS: A total of 118 individuals descendant from Europe, Asia, and Africa were studied. The genomic fragment of CR1 was amplified by polymerase chain reaction, and the SNPs and haplotypes were determined after DNA sequence analysis.

RESULTS: Among the six polymorphisms characterized, one of them was described for the first time. The analysis of allele frequency showed that these six SNPs did not differ between the European and Asian groups. The African group presented a higher frequency of alleles McCb, Sl2, and KAM+. The six polymorphisms gave origin to 12 haplotypes that were defined for the first time. The haplotypes 1 (4646A, Kna, McCa, Sl1, Sl4, KAM+), 2 (4646A, Kna, McCa, Sl1, KAM–), and 3 (4646A, Kna, McCa, Sl2, Sl4, KAM–) are the most frequent in all populations. The H2 presents similar frequency in all populations; however, whereas the H1 presented a higher prevalence in the European and Asian groups, in the African group H3 was present in a higher prevalence.

CONCLUSIONS: In this study, a new SNP substituting serine for asparagine at amino acid 1540 was identified. Moreover 12 haplotypes were identified. The differences in haplotype frequencies strongly suggest that the H1 and H2 might be the ancestral one while the H3 may have originated in Africa and may have fixed there by positive selection.
Human tissue oversight in hospitals: an AABB survey
Authors: Kuehnert Matthew J. , Yorita Krista L. , Holman Robert C. , Strong D. Michael ,   AABB Tissue Task Force
Published: December 2006

BACKGROUND: Reports of human tissue allograft–transmitted infections have underscored the need for better accounting of allografts in health‐care facilities. The Joint Commission on Accreditation of Healthcare Organizations (JCAHO) implemented new storage and issuance tissue standards for hospital oversight as of July 1, 2005. This study sought to survey hospital tissue responsibilities.

STUDY DESIGN AND METHODS: The AABB Tissue Task Force conducted a Web‐based survey distributed to all 904 hospital institutional members in January 2005. The survey asked about tissue type used, breadth of responsibility, hospital department involvement, and views on AABB involvement. Data from 402 of 904 (45%) respondents were tabulated and analyzed.

RESULTS: Among the 402 respondents, 325 (81%) used allogeneic and/or autologous human tissue. The most frequently used tissues were musculoskeletal (n = 240, 74%) and skin (n = 169, 52%) allografts. The department of surgery (e.g., operating room; n = 245, 76%) most often had responsibility for tissue use, followed by the blood bank (i.e., transfusion service; n = 164, 51%); surgery most frequently had responsibility for all tissue types except peripheral blood progenitor cells. Only 32 of 402 (8%) respondents had plans for increased oversight in the next 12 months; 129 of 178 (72%) thought there was a role for AABB in developing guidance on hospital tissue responsibilities.

CONCLUSIONS: In this survey, most AABB member hospital respondents indicated facility use of allogeneic and/or autologous tissues. Although tissue allograft responsibility by surgery was extensive, hospital blood banks also had significant involvement. Few blood banks, however, plan increased oversight in the near future. Given JCAHO standards, blood banks have an opportunity to assist their hospital in planning for assigned tissue responsibilities and oversight to ensure patient safety.
Concentration of transfusion resources on a few pathologies and a few patients: analysis of the comprehensive in‐hospital patient database
Authors: Beguin Claire , Closon Marie‐Christine , Vandekerckhove Philippe , Baele Philippe
Published: December 2006

BACKGROUND: Blood is a sparse commodity. Transfusion needs increase while the number of donors decreases. These constraints incite Belgian authorities to pay more attention to transfusion financing. This implies pathologic knowledge of the epidemiology of in‐hospital transfusion and the consumption of blood products.

STUDY DESIGN AND METHODS: This study is a retrospective analysis of in‐hospital stays from the year 2000 and includes data from all 124 Belgian hospitals. The database contains information on diagnoses, procedures, and all‐patients refined diagnosis‐related groups (APRDRGs) but also on expenses linked to blood products transfused and to transfusion‐related pharmaceutical products.

RESULTS: Three percent of surgical patients used 55.7 percent of transfusion resources and 75.4 percent of transfusion costs were associated with 24 APRDRGs. In the medical group, 3 percent of the patients accounted for 80.2 percent of transfusion costs and 20 APRDRGs consumed 71.9 percent of transfusion resources. The variables with the highest impact on the proportion of patients transfused were severity, pathology, and age. The effect of hospitals remained significant but had less impact. No substitution of blood products by transfusion‐related pharmaceutical products was observed in our analysis.

CONCLUSION: Our study confirms that transfusion now centers on a limited number of pathologic entities and, within those, in small subsets of patients. This implies that the costs linked to setting up and running the transfusion system can no longer be shared by a large number of patients who receive transfusions but rely increasingly on patients at higher risks of more unpredictable needs. The system must nevertheless be able to cope with them at any time.
“Sequential” Mapping Mimicking “Simultaneous” Mapping Using Magnetic Navigation During Catheter Ablation of Supraventricular Tachycardia: Results of the Single DX Study
Authors: ERNST SABINE , CHUN JULIAN K. R. , UJEYL AMAAR , OUYANG FEIFAN , KUCK KARL‐HEINZ
Published: December 2006

Introduction: The magnetic navigation system (MNS) allows remote‐controlled navigation of an ablation catheter from the control room. We tested the hypothesis, whether the MNS and a single additional diagnostic nonsteerable catheter would have the potential to identify the tachycardia substrate and allow subsequent ablation in patients with documented supraventricular tachycardia (SVT).

Methods and Results: A total of 41 patients (24 females, age 45 ± 16 years) underwent an invasive electrophysiologic (EP) study using the MNS. Together with a conventional diagnostic catheter in the right ventricle, the magnetic catheter (MC) was used to investigate the underlying EP substrate in a sequential fashion and subsequently to perform radiofrequency (RF) ablation. A custom‐made device allowed the separate assessment of fluoroscopy deployed from the control and examination room. Using conventional EP criteria, identification of the underlying substrate was possible in all but 4 noninducible patients (no accessory pathway [AP], no dual atrioventricular [AV] node): APs were present in 10 patients, AV node re‐entrant tachycardia in 26 patients, and ectopic atrial tachycardia in 1 patient. Despite 3 patients, in which switching to conventional ablation was necessary (8%), all others were successfully treated using the MNS. Overall fluoroscopy amounted to a median of 3.4 minutes (interquartile range, 2.4–5.3) with only a median of 1.0 minute exposure for the investigator.

Conclusions: Remote catheter ablation of SVT using the new MNS Niobe and a single conventional diagnostic catheter is feasible. Compared to conventional EP studies, a reduction of radiation exposure for both patients and investigators was demonstrated.
Association between antenatal depression and low birthweight in a developing country
Authors: Rahman A. , Bunn J. , Lovel H. , Creed F.
Published: December 2006

Objective:  There is a high prevalence of depression in south Asian women. We aimed to examine the association between antenatal depression and low birthweight (LBW) in infants in a rural community in Rawalpindi, Pakistan.

Method:  A total of 143 physically healthy mothers with ICD‐10 depression in the third trimester of pregnancy and 147 non‐depressed mothers of similar gestation were followed from birth. Infant weight was measured and information collected on socioeconomic status, maternal body‐mass index and sociodemographic factors.

Results:  Infants of depressed mothers had lower birthweight (mean 2910 g) than infants of non‐depressed mothers (mean 3022 g). The relative risk for LBW (≤2500 g) in infants of depressed mothers was 1.9 (95% CI 1.3–2.9). The association remained significant after adjustment for confounders by multivariate analyses.

Conclusion:  Low birthweight is a major public health problem in developing countries. Maternal depression during pregnancy predicts LBW. Interventions aimed at maternal depression may help improve infant outcomes.
Osseointegration of Osseotite® and machined‐surfaced titanium implants in membrane‐covered critical‐sized defects: a histologic and histometric study in dogs
Authors: Veis Alexander A. , Papadimitriou Serafim , Trisi Paolo , Tsirlis Anastasios T. , Parissis Nikolaos A. , Kenealy James N.
Published: December 2006

Abstract: The texture of an implant's surface can influence the rate and extent of bone fixation as expressed by the amount of linear bone‐to‐implant contact (BIC). The purpose of this study was to compare the bone density and linear BIC between Osseotite® and machined‐surface implants placed in bony defects without graft material and covered by a membrane. Thirty 2 mm diameter, 10 mm length custom implants were prepared for this study having a ‘split surface,’ with one side having the acid‐etched surface and the opposite side having a machined surface. Defects were created in the iliac wing of three adult mongrel dogs where a 6‐mm‐diameter drill was used to generate a 5‐mm‐deep defect. The implants were inserted into the center of the defect with 5 mm secured into the bone leaving 5 mm free in the defect with a 2 mm gap between the implant and surrounding bone. Expanded polytetrafluroethelyene membranes were placed over the defect sites stabilized with Biotack® pins. The healing times were 2, 3, and 5 months. Histologic and histometric analysis showed significantly lower BIC in the defect region as compared with the portion of implant placed into native bone for both implant surfaces in all groups. There was no difference in BIC values at 2‐ and 5‐month periods between the two surfaces in the regenerated area, while BIC values for Osseotite® surfaces were significantly higher than the machined surfaces at 3 months' healing time. Changes in bone density, observed between the three groups, affected correspondingly the BIC values in both implant surfaces, the effect being more pronounced in the Osseotite® surface.
Relationship between markers of metabolic control and inflammation on severity of periodontal disease in patients with diabetes mellitus
Authors: Lim L. P. , Tay F. B. K. , Sum C. F. , Thai A. C.
Published: December 2006

Aim: The aim of this study was to investigate the relationship between markers of metabolic control and inflammation and periodontal disease parameters in patients with diabetes.

Material & Methods: One hundred and eighty one adult patients with diabetes attending treatment at two diabetes centres were invited to participate in the study. Periodontal examination included full‐mouth assessment for probing depths and bleeding on probing (BOP). Blood analyses were carried out for glycated haemoglobin, (HbA1c), high‐sensitivity C reactive protein, (hsCRP) and lipid profile comprising total cholesterol, low‐density lipoprotein cholesterol (LDL chol), high‐density lipoprotein cholesterol (HDL chol) and triglycerides.

Results: Upon multivariate analysis, periodontal disease severity in terms of increased percentage of BOP and mean percentage of sites with probing depths 5 mm were found to be associated with inadequate glycaemic control as measured by HbA1c (p<0.01). HsCRP was also found to be a significant predictor for mean percentage of sites with probing depths 5 mm (p<0.05). After controlling for age, gender, smoking habits and number of teeth, positive correlations were found between HbA1c and percentage sites with probing depths 5 mm, percentage sites BOP, total cholesterol, LDL chol and triglycerides (p<0.05). Using the adjusted differences, subjects with acceptable glycaemic control (HbA1c <8%) showed a lower percentage of sites with BOP and probing depths 5 mm (p<0.05) when compared with those having inadequate glycaemic control. There was also a trend towards lower blood cholesterol in the well‐controlled group.

Conclusion: The level of glycaemic control as measured by HbA1c emerged as the most consistent risk factor associated with the extent and severity of periodontal disease in this study cohort.
Inhibition of MITF transcriptional activity independent of targeting p300/CBP coactivators
Authors: Vachtenheim Jiri , Šestáková Blanka , Tuháčková Zdena
Published: December 2006

Microphthalmia‐associated transcription factor (MITF) activates the expression of melanocyte‐specific markers and promotes the survival of embryonic, adult and malignant melanocytes. Although numerous MITF‐dependent downstream genes have been identified, the mechanisms by which the MITF activity is coregulated remain elusive. Here we used a non‐melanocytic cell line U2‐OS as a model in which MITF evokes transcription of a paradigmatic MITF target tyrosinase and show that the adenoviral E1A protein represses the MITF‐driven transcription in these cells. The E1A CR1 domain (which alone is insufficient to bind p300) was sufficient for repression, while the N‐terminus, through which E1A binds the p300/CBP proteins and other coactivators, was unable to repress. Correspondingly, CR1 inhibited colony formation of MITF‐positive, but not MITF‐negative, melanoma cells. The repression by CR1 was largely independent of the PCAF‐binding motif, previously recognized to be necessary for suppression of muscle‐specific enhancer. Interestingly, CR1 conferred transcriptional competence to the MITF‐CR1 chimera in which the MITF portion was rendered transcription‐deficient. Moreover, MITF mutants defective in binding to p300/CBP in vivo still activated transcription, further supporting a p300/CBP‐independent coactivation of MITF targets. MITF is amplified in a subset of melanomas and is thought to be required for sustained proliferation of malignant melanocytes. Our results suggest that understanding how CR1 represses Mitf activity may reveal a route to melanoma therapy.
Regulation of human skin pigmentation and responses to ultraviolet radiation
Authors: Miyamura Yoshinori , Coelho Sergio G. , Wolber Rainer , Miller Sharon A. , Wakamatsu Kazumasa , Zmudzka Barbara Z. , Ito Shosuke , Smuda Christoph , Passeron Thierry , Choi Wonseon , Batzer Jan , Yamaguchi Yuji , Beer Janusz Z. , Hearing Vincent J.
Published: December 2006

Pigmentation of human skin is closely involved in protection against environmental stresses, in particular exposure to ultraviolet (UV) radiation. It is well known that darker skin is significantly more resistant to the damaging effects of UV, such as photocarcinogenesis and photoaging, than is lighter skin. Constitutive skin pigmentation depends on the amount of melanin and its distribution in that tissue. Melanin is significantly photoprotective and epidermal cells in darker skin incur less DNA damage than do those in lighter skin. This review summarizes current understanding of the regulation of constitutive human skin pigmentation and responses to UV radiation, with emphasis on physiological factors that influence those processes. Further research is needed to characterize the role of skin pigmentation to reduce photocarcinogenesis and to develop effective strategies to minimize such risks.
Use of biomolecular templates for the fabrication of metal nanowires
Authors: Gazit Ehud
Published: December 2006

The nano‐scale spatial organization of metallic and other inorganic materials into 1D objects is a key task in nanotechnology. Nano‐scale fibers and tubes are very useful templates for such organization because of their inherent 1D organization. Fibrillar biological molecules and biomolecular assemblies are excellent physical supports on which to organize the inorganic material. Furthermore, these biological assemblies can facilitate high‐order organization and specific orientation of inorganic structures by their utilization of highly specific biological recognition properties. In this minireview, I will describe the use of biomolecules and biomolecular assemblies, including DNA, proteins, peptides, and even viral particles, which are excellent templates for 1D organization of inorganic materials into wires. This ranges from simple attempts at electroless deposition on inert biological templates to the advanced use of structural motifs and specific protein–DNA interactions for nano‐bio‐lithography as well as the fabrication of multilayer organic and inorganic composites. The potential technological applications of these hybrid biological–inorganic assemblies will be discussed.
Protein disulfide isomerase family proteins involved in soybean protein biogenesis
Authors: Wadahama Hiroyuki , Kamauchi Shinya , Ishimoto Masao , Kawada Teruo , Urade Reiko
Published: December 2006

Protein disulfide isomerase family proteins are known to play important roles in the folding of nascent polypeptides and the formation of disulfide bonds in the endoplasmic reticulum. In this study, we cloned two similar protein disulfide isomerase family genes from soybean leaf (Glycine maxL. Merrill cv. Jack) mRNA by RT‐PCR using forward and reverse primers designed from the expressed sequence tag clone sequences. The cDNA encodes a protein of either 364 or 362 amino acids, named GmPDIS‐1 or GmPDIS‐2, respectively. The nucleotide and amino acid sequence identities of GmPDIS‐1 and GmPDIS‐2 were 68% and 74%, respectively. Both proteins lack the C‐terminal, endoplasmic reticulum‐retrieval signal, KDEL. Recombinant proteins of both GmPDIS‐1 and GmPDIS‐2 were expressed inEscherichia colias soluble folded proteins that showed both an oxidative refolding activity of denatured ribonuclease A and a chaperone activity. Their domain structures were identified as containing two thioredoxin‐like domains, a and a′, and an ERp29c domain by peptide mapping with either trypsin or V8 protease. In cotyledon cells, both proteins were shown to distribute to the endoplasmic reticulum and protein storage vacuoles by confocal microscopy. Data from coimmunoprecipitation and crosslinking experiments suggested that GmPDIS‐1 associates with proglycinin, a precursor of the seed storage protein glycinin, in the cotyledon. Levels of GmPDIS‐1, but not of GmPDIS‐2, were increased in cotyledons, where glycinin accumulates during seed development. GmPDIS‐1, but not GmPDIS‐2, was induced under endoplasmic reticulum‐stress conditions.
Regulation of output from the plant circadian clock
Authors: Yakir Esther , Hilman Dror , Harir Yael , Green Rachel M.
Published: December 2006

Plants, like many other organisms, have endogenous biological clocks that enable them to organize their physiological, metabolic and developmental processes so that they occur at optimal times. The best studied of these biological clocks are the circadian systems that regulate daily (∼ 24 h) rhythms. At the core of the circadian system in every organism are oscillators responsible for generating circadian rhythms. These oscillators can be entrained (set) by cues from the environment, such as daily changes in light and temperature. Completing the circadian clock model are the output pathways that provide a link between the oscillator and the various biological processes whose rhythms it controls. Over the past few years there has been a tremendous increase in our understanding of the mechanisms of the oscillator and entrainment pathways in plants and many useful reviews on the subject. In this review we focus on the output pathways by which the oscillator regulates rhythmic plant processes. In the first part of the review we describe the role of the circadian system in regulation at all stages of a plant's development, from germination and growth to reproductive development as well as in multiple cellular processes. Indeed, the importance of a circadian clock for plants can be gauged by the fact that so many facets of plant development are under its control. In the second part of the review we describe what is known about the mechanisms by which the circadian system regulates these output processes.
Structural studies of thymidine kinases from Bacillus anthracis and Bacillus cereus provide insights into quaternary structure and conformational changes upon substrate binding
Authors: Kosinska Urszula , Carnrot Cecilia , Sandrini Michael P. B. , Clausen Anders R. , Wang Liya , Piskur Jure , Eriksson Staffan , Eklund Hans
Published: December 2006

Thymidine kinase (TK) is the key enzyme in salvaging thymidine to produce thymidine monophosphate. Owing to its ability to phosphorylate nucleoside analogue prodrugs, TK has gained attention as a rate‐limiting drug activator. We describe the structures of two bacterial TKs, one from the pathogen Bacillus anthracis in complex with the substrate dT, and the second from the food‐poison‐associated Bacillus cereus in complex with the feedback inhibitor dTTP. Interestingly, in contrast with previous structures of TK in complex with dTTP, in this study dTTP occupies the phosphate donor site and not the phosphate acceptor site. This results in several conformational changes compared with TK structures described previously. One of the differences is the way tetramers are formed. Unlike B. anthracis TK, B. cereus TK shows a loose tetramer. Moreover, the lasso‐domain is in open conformation in B. cereus TK without any substrate in the active site, whereas in B. anthracis TK the loop conformation is closed and thymidine occupies the active site. Another conformational difference lies within a region of 20 residues that we refer to as phosphate‐binding β‐hairpin. The phosphate‐binding β‐hairpin seems to be a flexible region of the enzyme which becomes ordered upon formation of hydrogen bonds to the α‐phosphate of the phosphate donor, dTTP. In addition to descriptions of the different conformations that TK may adopt during the course of reaction, the oligomeric state of the enzyme is investigated.
Attraction of Fruit‐Eating Bats with Essential Oils of Fruits: A Potential Tool for Forest Restoration
Authors: Bianconi Gledson V. , Mikich Sandra B. , Teixeira Sirlei D. , Maia Beatriz Helena L.N.S.
Published: December 2006

Previous tests with essential oils from ripe chiropterochoric fruits suggested they can be used to attract and capture fruit‐eating bats inside forest remnants. Here we evaluated the efficiency of these oils to attract frugivorous bats to open areas. We performed field tests with artificial fruits impregnated with essential oils of the genera Piper or Ficus that were attached to two groups of mist‐nets set 50 m outside the border of a forest remnant. One group of artificial fruits received the corresponding oil isolated through hydrodistillation and the other received water only. Fruits with oils attracted significantly more fruit‐eating bats, especially Artibeus lituratus that regularly crosses open habitats to reach other forest remnants. The highly significant attraction of A. lituratus by the oil of Piper was unexpected, since this bat is a specialist on Ficus fruits. We hypothesize that in habitats with no fruit available it is possible to attract frugivorous bats with the odor of several ripe fruit species. Furthermore, we verified that almost half of the individuals captured defecated seeds, indicating that the oils also attract recently fed bats, even when their preferred food is available nearby. This technique potentially may increase seed rain at specific locations, being particularly promising to restoration projects.
Maintenance of Specificity in an Isolated Fig
Authors: Harrison Rhett D.
Published: December 2006

The obligate interaction between figs and their pollinating wasps is often cited as an extraordinary example of reciprocal species specificity and evolutionary cospeciation. However, recent studies have shown that breakdowns in one‐to‐one specificity are not rare (30–60% of species depending on the locality). Combined with evidence of hybridization in some species, this led researchers to propose that a better evolutionary model was one of groups of genetically well‐defined pollinators coevolving with groups of frequently hybridizing figs. Nevertheless, these recent studies still indicate that a majority of fig species have one or more host‐specific pollinator. The extent to which specificity barriers in these species are leaky will have important consequences for the evolutionary process inFicus. At Lambir Hills N.P., Sarawak, a single individual ofFicus acamptophyllahas become recently isolated from conspecifics through clearance of its specialized habitat, but adjacent forest has a diverse fig flora, including 16 species with congeneric pollinators. Thus, when this individual flowered I was able to investigate the maintenance of its specificity barriers in the absence of competition from the normal pollinator. Only 1 percent of inflorescences were entered by a single pollinator species, which had very low reproductive success, and no viable seeds were produced. Nonpollinating wasps also failed to reproduce in any of the inflorescences. These results indicate the maintenance of strict specificity barriers in this fig individual.
The Influence of Hunting on Antipredator Behavior in Central African Monkeys and Duikers
Authors: Croes Barbara M. , Laurance William F. , Lahm Sally A. , Tchignoumba Landry , Alonso Alfonso , Lee Michelle E. , Campbell Patrick , Buij Ralph
Published: December 2006

Many animals can adjust their behavioral strategies to reduce predation risk. We investigated whether rain forest monkeys and duikers alter their antipredatory behavior in response to hunting by humans in southwestern Gabon. We compared monkey and duiker responses to human observers in an area where hunting is prohibited, to those in a nearby area where hunting pressure is moderate but spatially variable. The results of our study indicate that monkeys become more secretive when hunted, commencing alarm calls only when at a certain distance (typically > 50 m) from humans. We found no difference in monkey group size between hunted and no‐hunting areas. In no‐hunting areas, duikers often freeze in response to approaching observers, but in hunted areas they abandon this strategy and rapidly flee from humans. Duikers also whistle more often in areas where they are hunted frequently. Our findings have at least two important implications. First, behavioral observations of monkeys and duikers may be useful in gauging local hunting intensity in African rain forests. Second, duiker densities are likely to be overestimated in hunted areas, where they more readily flee and whistle, and underestimated in no‐hunting areas, where they rely on freezing behavior to avoid detection. Because behavioral adaptations to hunting vary both among species and localities, these differences should be considered when attempting to derive population‐density estimates for forest wildlife.
Puzzled by GRB 060218
Authors: Ghisellini G. , Ghirlanda G. , Tavecchio F.
Published: December 2006

We study the optical–UV/X-ray spectral energy distribution of GRB 060218 during the prompt and what seems to be the afterglow phases. The results are puzzling, since if the optical–UV and the X-ray emission belong to a single blackbody then its luminosity is too large, and this blackbody cannot be interpreted as the signature of the shock breakout of the supernova. There are also serious problems in associating the emission expected from the supernova shock breakout with either the optical–UV or the X-ray emission. In the former case we derive too small ejecta velocities; in the latter case, in contrast, the required velocity is too large, corresponding to the large radius of a blackbody required to peak close to the UV band. We then present what we think is the most conservative alternative explanation, namely a synchrotron spectrum, self-absorbed in the optical–UV and extending up to the X-ray band, where we observe the emission of the most energetic electrons, which are responsible for the exponential roll-over of the spectrum. The obtained fit can explain the entire spectrum except the blackbody observed in the X-rays, which must be a separate component. The puzzling feature of this interpretation is that the same model is required to explain the spectrum also at later times, up to 105 s, because the optical–UV emission remains constant in shape and also (approximately) in normalization. In this case the observed X-ray flux is produced by self-Compton emission. Thus the prompt emission phase should last for ∼105 s or more. Finally, we show that the blackbody observed in X-rays, up to 7000 s, can be photospheric emission from the cocoon or stellar material, energized by the gamma-ray burst jet at radii comparable to the stellar radius (i.e. 1010–1011 cm), not very far from where this material becomes transparent (e.g. 1012 cm).
Morality and Psychology
Authors: Andreou Chrisoula
Published: December 2006

This article briefly discusses the connection between moral philosophy and moral psychology, and then explores three intriguing areas of inquiry that fall within the intersection of the two fields. The areas of inquiry considered focus on (1) debates concerning the nature of moral judgments and moral motivation; (2) debates concerning good and bad character traits and character‐based explanations of actions; and (3) debates concerning the role of moral rules in guiding the morally wise agent.
Liposuction – removal of giant lipomas for weight loss in a dog with severe hip osteoarthritis
Authors: Böttcher P. , Klüter S. , Krastel D. , Grevel V.
Published: December 2006

An extremely obese, mixed breed dog, with severe bilateral hip osteoarthritis was presented with progressive hindlimb lameness. In addition, three giant lipomas were diagnosed, one causing mechanical irritation within the left axillary region. Previous treatments of dietary weight loss and non‐steroidal anti‐inflammatory drugs had failed. Minimally invasive liposuction of the lipomas was performed, resulting in weight loss of 3 kg, representing 10 per cent of the dog’s bodyweight. Conservative treatment was continued, and the dog improved rapidly postoperatively. Liposuction of lipomas may be considered as an alternative to traditional surgical resection in cases where seroma formation and delayed wound healing may be expected. Acute weight loss through liposuction may improve lameness associated with osteoarthritis and motivate the owner compliance for further weight loss.
Pontine infarction in a dog with unilateral involvement of the trigeminal motor nucleus and pyramidal tract
Authors: Palmer A. C.
Published: December 2006

An unusual case of unilateral trigeminal neuronopathy in a dog is reported, in which the motor nucleus of the trigeminal nerve and the ipselateral corticospinal tract were destroyed, apparently by a cerebrovascular accident (stroke). Hemiplegia did not occur. Neuropathological changes are described, including remyelination by Schwann cells in the central nervous system. The case illustrates the importance of central nervous system post‐mortem examination when establishing causes of cranial nerve paralysis.
THE IMPORTANCE OF CONSIDERING PREDICTION VARIANCE IN ANALYSES USING PHOTOGRAMMETRIC MASS ESTIMATES
Authors: Proffitt Kelly M. , Garrott Robert A. , Rotella Jay J. , Banfield Jeff
Published: December 2006

Abstract

Development and application of photogrammetric mass‐estimation techniques in marine mammal studies is becoming increasingly common. When a photogrammetrically estimated mass is used as a covariate in regression modeling, the error associated with estimating mass induces bias in regression statistics and decreases model explanatory power. Thus, it is important to understand and account for prediction variance when addressing ecological questions that require use of estimated mass values. In a simulation study based on data collected from Weddell seals, we developed regression models of pup weaning mass as a function of maternal postparturition mass where maternal mass was directly measured and second where maternal mass was photogrammetrically estimated. We demonstrate that when estimated mass was used, the regression coefficient was biased toward zero and the coefficient of determination was 30% less than the value obtained when using maternal postparturition mass obtained from direct measurement. After applying bias correction procedures, however, the regression coefficient and coefficient of determination were within 2% of their true values. To effectively use photogrammetrically estimated masses, prediction variance should be understood and accounted for in all analyses. The methods presented in this paper are effective and simple techniques to explore and account for prediction variance.
LESSONS FROM MONITORING TRENDS IN ABUNDANCE OF MARINE MAMMALS
Authors: Taylor Barbara L. , Martinez Melissa , Gerrodette Tim , Barlow Jay , Hrovat Yvana N.
Published: December 2006

Abstract

We assessed scientists' ability to detect declines of marine mammal stocks based on recent levels of survey effort, when the actual decline is precipitous. We defined a precipitous decline as a 50% decrease in abundance in 15 yr, at which point a stock could be legally classified as “depleted” under the U.S. Marine Mammal Protection Act. We assessed stocks for three categories of cetaceans: large whales (n= 23, most of which are listed as endangered), beaked whales (n= 11, potentially vulnerable to anthropogenic noise), and small whales/dolphins/porpoises (n= 69, bycatch in fisheries and important abundant predators), for two categories of pinnipeds with substantially different survey precision: counted on land (n= 13) and surveyed on ice (n= 5), and for a category containing polar bear and sea otter stocks (n= 6). The percentage of precipitous declines that wouldnotbe detected as declines was 72% for large whales, 90% for beaked whales, and 78% for dolphins/porpoises, 5% for pinnipeds on land, 100% for pinnipeds on ice, and 55% for polar bears/sea otters (based on a one‐tailedt‐test, α= 0.05), given the frequency and precision of recent monitoring effort. We recommend alternatives to improve performance.
TURNING MANEUVERS IN STELLER SEA LIONS (EUMATOPIAS JUBATUS)
Authors: Cheneval O. , Blake R. W. , Trites A. W. , Chan K. H. S.
Published: December 2006

Abstract

Steller sea lions are highly maneuverable marine mammals (expressed as minimum turning radius). Video recordings of turns (n= 195) are analyzed from kinematic measurements for three captive animals. Speed‐time plots of 180° turns have a typical “V‐shape.” The sea lions decelerated during the first half of the turn, reached a minimum speed in the middle of the curved trajectory and reaccelerated by adduction of the pectoral flippers. The initial deceleration was greater than that for passive gliding due to pectoral flipper braking and/or change in body contour from a stiff, straight streamlined form. Centripetal force and thrust were determined from the body acceleration. Most thrust was produced during the power phase of the pectoral flipper stroke cycle. Contrary to previous findings on otariids, little or no thrust was generated during initial abduction of the pectoral flippers and during the final drag‐based paddling phase of the stroke cycle. Peak thrust force at the center of gravity occurs halfway through the power phase and the centripetal force is maximal at the beginning of the power stroke. Performance is modulated by changes in the duration and intensity of movements without changing their sequence. Turning radius, maximum velocity, maximum acceleration and turning duration were 0.3 body lengths, 3.5 m/s, 5 m/s2, and 1.6 s, respectively. The relative maneuverability based on velocity and length specific minimum turning radius is comparable to other otariids, superior to cetaceans but inferior to many fish.
THE DREAM OF PERFECTION
Authors: MacKenna Christopher
Published: December 2006

abstract  Psychoanalytic thinking is suspicious of the notion of perfection, whereas Christian (and other religious) thinking allows an important place to it. Is psychoanalytic hostility justified, or is it part of the depressive mind‐set which even some insiders have attributed to the analytic perspective? With help from George Bernard Shaw and Robert Browning, this paper explores the reasons for therapeutic suspicion, but also considers Jesus’ teaching about perfection. Following leads offered by Matte Blanco, Jung and others, it argues for the spiritual and therapeutic value of making space for a dream of perfection – but it also highlights the murderous consequences of allowing the dream to become concretized.
Eastern bluebirds Sialia sialis do not avoid nest boxes with chemical cues from two common nest predators
Authors: Godard Renee D. , Bowers Bonnie B. , Morgan Wilson C.
Published: December 2006

Chemodetection of common nest predators may be advantageous for nesting birds; however, few studies have examined the ability of songbirds to detect chemical odors from predators. Thus, in 2002, we presented eastern bluebirds Sialia sialis with pairs of nest boxes; one box in the pair was regularly scented with chemical cues from a common nest predator, the black rat snake Elaphe obsoleta, and the other with a neutral cue. In 2004, we again presented bluebirds with pairs of boxes, one scented with chemical cues from a different nest predator, the deer mouse Peromyscus maniculatus, and the other with a neutral scent. Although human females were able to correctly distinguish paper laced with predator cues from paper with neutral cues, bluebirds were as likely to lay eggs in boxes with predator cues as in boxes with neutral cues. While it remains possible that bluebirds may detect scent from potential nest predators, it appears that the presence of these chemical cues does not ultimately influence selection of nest sites.
A Comparison of Single and Multiphase Jets in a Crossflow Using Large Eddy Simulations
Authors: Salewski Mirko , Stankovic Dragan , Fuchs Laszlo
Published: December 2006

Large eddy simulations (LES) are performed for single and multiphase jets in crossflow (JICF). The multiphase JICF are compared to the single-phase case for the same momentum and mass flow ratios but with droplets of different sizes. Multiphase JICF have stronger counterrotating vortex pairs (CVPs) than a corresponding single-phase JICF. Moreover, their trajectories are higher and their induced wakes weaker. The smaller the Stokes number of the droplets, the more the solution approaches the solution for single-phase flow. The computed results show the formation of a CVP and horseshoe vortices, which are convected downstream. LES also reveals the intermittent formation of upright wake vortices from the horseshoe vortices on the ground toward the CVP. The dispersion of polydisperse spray droplets is computed using the stochastic parcel method. Atomization and droplet breakup are modeled by a combination of the breakup model by Reitz and the Taylor analogy breakup model (see Caraeni, D., Bergström, C., and Fuchs, L., 2000, Flow, Turbul. Combust., 65(2), pp. 223–244). Evaporation and droplet collision are also modeled. The flow solver uses two-way coupling. Averages of the velocity and gaseous fuel mass fraction are computed. The single-phase JICF is validated against experimental data obtained by PIV. Additionally, the PDFs and frequency spectra are presented.
Some Experiments on Oil Whirl and Oil Whip
Authors: El-Shafei A. , Tawfick S. H. , Raafat M. S. , Aziz G. M.
Published: December 2006

The oil whirl and oil whip phenomena have been well known since the early twentieth century. However, there is a lot of confusion on the parameters that affect the onset of instability. In this study, we investigate the onset of instability on a flexible rotor mounted on two plain cylindrical journal bearings. The rotor is run through the first critical speed, the instability, and the second critical speed. Tests are conducted at various unbalance levels, pressures, and misalignment conditions on the coupling. It is shown that, by far, the misalignment of the coupling is the parameter that is most effective on the onset of instability. In particular angular misalignment resulted in the smoothest rotor response.
Combustion Instabilities and Control of a Multiswirl Atmospheric Combustor
Authors: Yi Tongxun , Gutmark Ephraim J.
Published: December 2006

Thermoacoustic instability and lean blowout (LBO) are investigated experimentally in an atmospheric swirl-stabilized combustor fueled with gaseous propane. Factors affecting combustion instability are identified. Sinusoidal or steady air forcing of either the swirling air shear layer or the fuel line, with less than 1.0% of combustion air, can reduce pressure oscillations amplitude by more than 20dB. Phase-shifted close-loop air forcing of the flame can reduce the pressure oscillations amplitude by 13dB. For a constant air flow rate and air inlet temperature, initially smooth turbulent combustion exhibits relatively intense heat release oscillations with decreasing equivalence ratio, followed by a quiet state before blowout. High outer swirl intensity and a rich burning flame stabilization region can effectively extend the LBO limit.
Modeling Diesel Spray Flame Liftoff, Sooting Tendency, and NOx Emissions Using Detailed Chemistry With Phenomenological Soot Model
Authors: Kong Song-Charng , Sun Yong , Rietz Rolf D.
Published: December 2006

A detailed chemistry-based CFD model was developed to simulate the diesel spray combustion and emission process. A reaction mechanism of n-heptane is coupled with a reduced NOx mechanism to simulate diesel fuel oxidation and NOx formation. The soot emission process is simulated by a phenomenological soot model that uses a competing formation and oxidation rate formulation. The model is applied to predict the diesel spray lift-off length and its sooting tendency under high temperature and pressure conditions with good agreement with experiments of Sandia. Various nozzle diameters and chamber conditions were investigated. The model successfully predicts that the sooting tendency is reduced as the nozzle diameter is reduced and/or the initial chamber gas temperature is decreased, as observed by the experiments. The model is also applied to simulate diesel engine combustion under premixed charge compression ignition (PCCI) conditions. Trends of heat release rate, NOx, and soot emissions with respect to EGR levels and start-of-injection timings are also well predicted. Both experiments and models reveal that soot emissions peak when the start of injection (SOI) occurs close to TDC. The model indicates that low soot emission at early SOI is due to better oxidation while low soot emission at late SOI is due to less formation. Since NOx emissions decrease monotonically with injection retardation, a late injection scheme can be utilized for simultaneous soot and NOx reduction for the engine conditions investigated in this study.
Supplementary Backward Equations T(p,h), v(p,h), and T(p,s), v(p,s) for the Critical and Supercritical Regions (Region 3) of the Industrial Formulation IAPWS-IF97 for Water and Steam
Authors: Kretzschmar H.-J. , Cooper J. R. , Dittmann A. , Friend D. G. , Gallagher J. S. , Harvey A. H. , Knobloch K. , Mareš R. , Miyagawa K. , Okita N. , Stöcker I. , Wagner W. , Weber I.
Published: December 2006

In modeling advanced steam power cycles, thermodynamic properties as functions of pressure and enthalpy (p,h) or pressure and entropy (p,s) are required in the critical and supercritical regions (region 3 of IAPWS-IF97). With IAPWS-IF97, these calculations require cumbersome two-dimensional iteration of temperature T and specific volume v from (p,h) or (p,s). While these calculations in region 3 are not frequently required, the computing time can be significant. Therefore, the International Association for the Properties of Water and Steam (IAPWS) adopted backward equations for T(p,h), v(p,h), T(p,s), and v(p,s) in region 3, along with boundary equations for the saturation pressure as a function of enthalpy, p3sat(h), and of entropy, p3sat(s). Using the new equations, two-dimensional iteration can be avoided. The numerical consistency of temperature and specific volume obtained in this way is sufficient for most uses. This paper summarizes the need and the requirements for these equations and gives complete numerical information. In addition, numerical consistency and computational speed are discussed.
Open-Loop Active Control of Combustion Dynamics on a Gas Turbine Engine
Authors: Richards Geo. A. , Thornton Jimmy D. , Robey Edward H. , Arellano Leonell
Published: December 2006

Combustion dynamics is a prominent problem in the design and operation of low-emission gas turbine engines. Even modest changes in fuel composition or operating conditions can lead to damaging vibrations in a combustor that was otherwise stable. For this reason, active control has been sought to stabilize combustors that must accommodate fuel variability, new operating conditions, etc. Active control of combustion dynamics has been demonstrated in a number of laboratories, single-nozzle test combustors, and even on a fielded engine. In most of these tests, active control was implemented with closed-loop feedback between the observed pressure signal and the phase and gain of imposed fuel perturbations. In contrast, a number of recent papers have shown that open-loop fuel perturbations can disrupt the feedback between acoustics and heat release that drives the oscillation. Compared to the closed-loop case, this approach has some advantages because it may not require high-fidelity fuel actuators, and could be easier to implement. This paper reports experimental tests of open-loop fuel perturbations to control combustion dynamics in a complete gas turbine engine. Results demonstrate the technique was very successful on the test engine and had minimal effect on pollutant emissions.