bluuebunny/crossref_metadata_2025 huggingface dataset:
Processing and on-wafer test of ferroelectric film microwave varactors
Authors: Kim J.-Y. , Grishin A. M.
Published: May 2006

We present comparative characteristics of microwave variable capacitors (varactors) fabricated on Na0.5K0.5NbO3 (NKN), AgTa0.5Nb0.5O3 (ATN), and Ba0.5Sr0.5TiO3 (BST) ferroelectric films grown by rf-magnetron sputtering (NKN) and pulsed laser deposition (ATN and BST) techniques on the sapphire. Two port 2μm finger gap coplanar waveguide interdigital capacitors (CPWIDCs) were defined on ferroelectric films surface by photolithographic lift-off technique. Deembedding method was employed to extract properties of CPWIDC from the S parameters measured in microwave range up to 40GHz. BST films on sapphire substrates show superior tunability of 26% (20GHz, 200kV∕cm), whereas ATN films possess the lowest tanδ=0.06 at 20GHz and extremely low dispersion of 4.3% in a whole frequency range of 45MHz–40GHz.
Life-history traits and the mating system of an Australian water strider, Tenagogerris euphrosyne
Authors: Colvin Paul G. R. , Elgar Mark A. , Jones Therésa M.
Published: May 2006

The hemipteran infraorder Gerromorpha (the semiaquatic bugs, or water striders) has been used extensively as a model taxon in evolutionary biology and ecology. Most studies have focused on North American and European species while there is a paucity of comparable data on the gerromorphs of Africa and Australia. In a series of laboratory experiments we explore patterns of ontogenetic development, foraging and mating behaviour in Tenagogerris euphrosyne (Kirkaldy), a medium-sized water strider distributed along the east coast of Australia. Our study revealed that T. euphrosyne nymphs passed through five instars before adulthood, but that mortality and rates of cannibalism were high. Foraging and mating trials revealed that the foraging success of adult males (but not females) was positively correlated with mating success. Observations indicated that T. euphrosyne exhibits a Type I water strider mating behaviour: mating followed a brief period of struggling by the female, after which males were able to ride on a female’s back for extended periods. Females gained direct fertility benefits from mating and were able to store sperm and lay fertilised eggs (albeit a reduced quantity) for several weeks even in the absence of males.
Dissection of Swa2p/Auxilin Domain Requirements for Cochaperoning Hsp70 Clathrin-uncoating Activity In Vivo
Authors: Xiao Jing , Kim Leslie S. , Graham Todd R.
Published: May 2006

The auxilin family of J-domain proteins load Hsp70 onto clathrin-coated vesicles (CCVs) to drive uncoating. In vitro, auxilin function requires its ability to bind clathrin and stimulate Hsp70 ATPase activity via its J-domain. To test these requirements in vivo, we performed a mutational analysis of Swa2p, the yeast auxilin ortholog. Swa2p is a modular protein with three N-terminal clathrin-binding (CB) motifs, a ubiquitin association (UBA) domain, a tetratricopeptide repeat (TPR) domain, and a C-terminal J-domain. In vitro, clathrin binding is mediated by multiple weak interactions, but a Swa2p truncation lacking two CB motifs and the UBA domain retains nearly full function in vivo. Deletion of all CB motifs strongly abrogates clathrin disassembly but does not eliminate Swa2p function in vivo. Surprisingly, mutation of the invariant HPD motif within the J-domain to AAA only partially affects Swa2p function. Similarly, a TPR point mutation (G388R) causes a modest phenotype. However, Swa2p function is abolished when these TPR and J mutations are combined. The TPR and J-domains are not functionally redundant because deletion of either domain renders Swa2p nonfunctional. These data suggest that the TPR and J-domains collaborate in a bipartite interaction with Hsp70 to regulate its activity in clathrin disassembly.
Ongoing U snRNP Biogenesis Is Required for the Integrity of Cajal Bodies
Authors: Lemm Ira , Girard Cyrille , Kuhn Andreas N. , Watkins Nicholas J. , Schneider Marc , Bordonné Rémy , Lührmann Reinhard
Published: May 2006

Cajal bodies (CBs) have been implicated in the nuclear phase of the biogenesis of spliceosomal U small nuclear ribonucleoproteins (U snRNPs). Here, we have investigated the distribution of the CB marker protein coilin, U snRNPs, and proteins present in C/D box small nucleolar (sno)RNPs in cells depleted of hTGS1, SMN, or PHAX. Knockdown of any of these three proteins by RNAi interferes with U snRNP maturation before the reentry of U snRNA Sm cores into the nucleus. Strikingly, CBs are lost in the absence of hTGS1, SMN, or PHAX and coilin is dispersed in the nucleoplasm into numerous small foci. This indicates that the integrity of canonical CBs is dependent on ongoing U snRNP biogenesis. Spliceosomal U snRNPs show no detectable concentration in nuclear foci and do not colocalize with coilin in cells lacking hTGS1, SMN, or PHAX. In contrast, C/D box snoRNP components concentrate into nuclear foci that partially colocalize with coilin after inhibition of U snRNP maturation. We demonstrate by siRNA-mediated depletion that coilin is required for the condensation of U snRNPs, but not C/D box snoRNP components, into nucleoplasmic foci, and also for merging these factors into canonical CBs. Altogether, our data suggest that CBs have a modular structure with distinct domains for spliceosomal U snRNPs and snoRNPs.
Role of ITAM‐containing adapter proteins and their receptors in the immune system and bone
Authors: Humphrey Mary Beth , Lanier Lewis L. , Nakamura Mary C.
Published: May 2006

Summary:  The immunoreceptor tyrosine‐based activation motif (ITAM) is a highly conserved region in the cytoplasmic domain of signaling chains and receptors and is a critical mediator of intracellular signals. ITAM‐mediated signals depend on the Syk or ζ‐associated protein of 70 kDa tyrosine kinases, and ITAM signaling is required for the differentiation and function of B and T cells in adaptive immunity. ITAM‐dependent receptors also regulate the function of innate immune cells, including natural killer cells, and myeloid‐derived cells such as macrophages, neutrophils, dendritic cells, and mast cells. Myeloid lineage cells also include osteoclasts (OCLs), the cells required for bone resorption, and recent studies show a critical role for the ITAM‐containing adapter proteins DAP12 and the FcRγ chain (Fcɛ receptor I γ chain) in OCL differentiation. Mice deficient in both the DAP12 and FcRγ ITAM‐bearing adapters are significantly osteopetrotic with a severe defect in OCL differentiation, demonstrating the requirement for ITAM signals in bone and further implicating this pathway in the development of highly specialized cell functions in hematopoietic cells. Regulation of osteoclastogenesis by ITAM‐dependent receptors suggests that OCLs, similar to related myeloid cells, are tightly controlled by arrays of receptors that allow them to sense and respond to their local microenvironment like other innate immune cells.
Immune responses and bone loss: the estrogen connection
Authors: Carlsten Hans
Published: May 2006

Summary:  In addition to its effects on sexual differentiation and reproduction, estrogen has important impact on the immune system and on bone. It has also been evident that the effects of estrogen on bone to a large extent are mediated via its action on immune cells. Estrogen has a dichotomous impact on the immune system by downregulation of inflammatory immune responses but simultaneous upregulation of immunoglobulin production. Consequently, immune‐mediated diseases in humans and in animal models are modulated by estrogen. Estrogen deficiency after ovariectomy in mice and after menopause in women is associated with significant bone loss. In rheumatic diseases such as rheumatoid arthritis (RA), osteoporosis is frequent, and in patients with postmenopausal RA, the degree of bone loss is dramatically increased. Hormone replacement therapy (HRT) in murine and human arthritis has beneficial effects on bone loss, as expected, but it also ameliorates inflammation and inflammation‐triggered joint destruction. Long‐term use of HRT has been associated with increased risk of breast cancer, thrombosis, and possibly also stroke. Accordingly, there is great need for new activators of estrogen receptors (ERs) selectively reproducing only the beneficial effects of estrogen. To achieve this aim, better knowledge of the mechanisms of how activation of ER‐α and ER‐β modulates the immune system and bone at the cellular and molecular levels is necessary.
Genetic analyses in patients with familial isolated hyperparathyroidism and hyperparathyroidism–jaw tumour syndrome
Authors: Mizusawa Noriko , Uchino Shinya , Iwata Takeo , Tsuyuguchi Masaru , Suzuki Yasuyo , Mizukoshi Tsunenori , Yamashita Yoshio , Sakurai Akihiro , Suzuki Shinichi , Beniko Mutsuo , Tahara Hideki , Fujisawa Masato , Kamata Nobuyuki , Fujisawa Kenji , Yashiro Tohru , Nagao Daisuke , Golam Hossain Md. , Sano Toshiaki , Noguchi Shiro , Yoshimoto Katsuhiko
Published: May 2006

Background  A subset of familial isolated primary hyperparathyroidism (FIHP) is a variant of hyperparathyroidism–jaw tumour syndrome (HPT‐JT).

Aim/patients and methods  We investigated the involvement of the HRPT2, MEN1 and CASR genes in 11 provisional FIHP families and two HPT‐JT families.

Results  Germline mutations of HRPT2 were found in two of the 11 FIHP families and one of the two HPT‐JT families. One FIHP family with parathyroid carcinoma and atypical adenomas and another FIHP family with cystic parathyroid adenoma had novel frameshift mutations of 518–521del and 62–66del, respectively. In a patient with HPT‐JT, a de novo germline mutation of 39delC was detected. Novel somatic HRPT2 mutations of 70–73del and 95–102del were found in two of five parathyroid tumours in a family with a 518–521del mutation. Biallelic inactivation of HRPT2 by a combination of germline and somatic mutation was confirmed in the parathyroid tumours. The finding that two families diagnosed with FIHP carried HRPT2 mutations suggests that they have occult HPT‐JT. In the remaining 10 families, one family had a missense MEN1 mutation. No mutations of CASR were detected.

Conclusion  Our results confirm the need to test for HRPT2 in FIHP families, especially those with parathyroid carcinomas, atypical adenomas or adenomas with cystic change.
Sirolimus pharmacokinetics in pediatric renal transplant recipients receiving calcineurin inhibitor co‐therapy
Authors: Schachter Asher D. , Benfield Mark R. , Wyatt Robert J. , Grimm Paul C. , Fennell Robert S. , Herrin John T. , Lirenman David S. , McDonald Ruth A. , Munoz‐Arizpe Ricardo , Harmon William E.
Published: May 2006

Abstract:  We have previously reported sirolimus (SRL) pharmacokinetics (PK) in pediatric renal transplant recipients on a calcineurin inhibitor (CNI)‐free protocol. We now report pediatric SRL PK in pediatric renal transplant patients receiving SRL + CNI. SRL was dosed to achieve target trough levels between 10 and 20 ng/mL. We performed 49 SRL PK profiles in pediatric renal transplant recipients receiving SRL in combination with either cyclosporine (CsA; 25 profiles), or tacrolimus (TCL; 24 profiles). Ten of the SRL + TCL profiles were obtained from children receiving SRL on a b.i.d. dosing regimen. All other SRL profiles were q.d. regimens. We calculated, the maximum concentration (Cmax), AUC, apparent clearance (aCL; dose/AUC) for dose in mg/m2, and mean residence time (MRT). SRL levels were measured at 6 and 7 time points for b.i.d. and q.d. dosing, respectively. Regression analysis of SRL trough values vs. AUC showed good correlation in the SRL q.d. + CsA, SRL q.d. + TCL, and SRL b.i.d. + TCL groups (r2 = 0.95, 0.68, and 0.44, respectively). SRL aCL corrected for body surface area was higher in children aged 0–5 yr receiving SRL with either CsA or TCL. SRL dosing schedule should be tailored to each patient. Higher SRL aCL may be present in younger children when administered with CNI.
Analysis of the effect of aluminum in drinking water and transferrin C2 allele on Alzheimer's disease
Authors: Rondeau V. , Iron A. , Letenneur L. , Commenges D. , Duchêne F. , Arveiler B. , Dartigues J.‐F.
Published: May 2006

Although highly controversial, the hypothesis of a link between aluminum (Al) in drinking water and Alzheimer's disease (AD) has been supported by several epidemiological studies. Transferrin (Tf) is a major transport protein for both iron and Al. Moreover, it has been demonstrated that defective binding of iron and Al to the Tf variant C2 could be present in AD. Individuals carrying the Tf C2 allele might therefore be at greater risk of developing AD. We investigated whether the Tf C2 allele might be responsible for susceptibility to AD in a sample of 292 subjects (with 55 AD) aged ≥75 years from south‐west France, some exposed to high levels of Al in tap water (n = 181 subjects) and others to low levels of Al (n = 111 subjects). We also examined the combined genetic effects of Tf C2 and ɛ4 allele of apolipoprotein E gene (ApoE). Logistic regression analysis showed that neither Tf C2 nor its interaction with Al or with the ɛ4 allele of the ApoE were significantly associated with the risk of AD.
Hypoxia‐induced ischemic tolerance in neonatal rat brain involves enhanced ERK1/2 signaling
Authors: Jones Nicole M. , Bergeron Marcelle
Published: May 2006

Hypoxic preconditioning (HP) 24 h before hypoxic‐ischemic (HI) injury confers significant neuroprotection in neonatal rat brain. Recent studies have shown that the mitogen‐activated protein kinase (MAPK) and phosphatidylinositol‐3‐kinase (PI3K) intracellular signaling pathways play a role in the induction of tolerance to ischemic injury in heart and brain. To study the role of MAPK (ERK1/2, JNK, p38MAPK) and PI3K/Akt/GSK3β signaling pathways in hypoxia‐induced ischemic tolerance, we examined the brains of newborn rats at different time points after exposure to sublethal hypoxia (8% O2for 3 h). Immunoblot analysis showed that HP had no effect on the levels of phosphorylated Akt, GSK3β, JNK and p38MAPK. In contrast, significantly increased levels of phosphorylated ERK1/2 were observed 0.5 h after HP. Double immunofluorescence staining showed that hypoxia‐induced ERK1/2 phosphorylation was found mainly in microvessels throughout the brain and in astrocytes in white matter tracts. Inhibition of hypoxia‐induced ERK1/2 pathway with intracerebral administration of U0126 significantly attenuated the neuroprotection afforded by HP against HI injury. These findings suggest that activation of ERK1/2 signaling may contribute to hypoxia‐induced tolerance in neonatal rat brain in part by preserving vascular and white matter integrity after HI.
Distribution of hepatitis B virus genotypes among patients with chronic infection
Authors: Caldas Ribeiro Nadia Regina , Soares Campos Gubio , Dias Angelo Ana Luiza , Lorens Braga Eduardo , Santana Nelma , Mesquita Soares Gomes Michele , Rebello Pinho Joao Renato , Andrade De Carvalho Wilson , Costa Lyra Luiz Guilherme , Castro Lyra Andre
Published: May 2006

Abstract: Hepatitis B virus (HBV) can be classified into at least eight genotypes, A–H. We evaluated the distribution HBV genotypes among patients with chronic infection.

Methods: We consecutively evaluated adult patients with chronic HBV infection from Salvador, Brazil. Patients were classified according to HBV infection chronic phases based on HBV‐DNA levels and presence of serum HBV markers. HBV‐DNA was qualitatively and quantitatively detected in serum by polymerised chain reaction (PCR). Isolates were genotyped by comparison of amino acid mutations and phylogenetic analysis.

Results: One‐hundred and fourteen patients were evaluated. HBV‐DNA was positive in 96 samples. HBV genotype was done in 76. Mean age was 36±11.3. In 61 of 76 cases subjects were classified as inactive HBsAg carriers. Their mean HBV serum level was 1760 copies/ml and 53 of 61 were infected with HBV genotype A, seven with HBV genotype F and one with genotype B. Twelve of the 76 patients had detectable hepatitis B e‐antigen (HBeAg) in serum. Ten were infected with HBV genotype A and two with genotype F; most had increased alanine aminotransferase and high HBV‐DNA levels. Three patients were in the immunotolerant phase, two were infected with HBV genotype A and one with genotype F. HBV subtyping showed subtypes adw2 and adw4.

Conclusions: HBV genotype A adw2 and genotype F adw4 were the most prevalent isolates found. We could not find differences in genotype distribution according to HBV clinical phases and DNA levels. We did not detect HBV genotype D in contrast to a previous study in our center with acute hepatitis B. All inactive HBsAg carriers had low HBV‐DNA levels.
Normal Performance on a Simulated Gambling Task in Treatment‐Naïve Alcohol‐Dependent Individuals
Authors: Fein George , McGillivray Shannon , Finn Peter
Published: May 2006

Background: Research suggests that substance abusers make more disadvantageous decisions on the simulated gambling task (SGT); such decisions are associated with deviance proneness and antisocial symptoms. This study examines decision making on the SGT in young adults with alcohol dependence who are treatment‐naïve (TxN).

Methods: A total of 116 subjects (58 controls, 58 TxNs) were tested on the SGT, where participants choose cards from 4 different decks that vary in terms of the magnitude of the immediate gain (large/small) and the magnitude of long‐term loss (larger/smaller). Participants were also assessed on measures of externalizing symptoms, personality traits reflecting social deviance, neuropsychological function, and the density of the family history of alcoholism.

Results: Treatment‐naïves did not differ from controls on measures of SGT decision making. Simulated gambling task performance was not associated with externalizing symptoms, social deviance proneness, or a familial density of alcoholism. Although TxNs had higher levels of externalizing symptoms, social deviance, and familial density of alcoholism compared with controls, these variables were only modestly elevated compared with previous samples of long‐term abstinent alcohol‐dependent individuals who showed decision‐making deficits on the SGT.

Conclusions: The results suggest that our sample of young adult TxN adults with alcohol dependence do not have global deficits in decision making as measured by the SGT, and that their poor decisions regarding their alcohol consumption are more specific to drinking.
Plasma Oxidation of a Titanium Electrode in dc‐Plasma Above the Water Surface
Authors: Matsushima Yuta , Yamazaki Tsutomu , Maeda Kazuyuki , Noma Tatsuo , Suzuki Takeyuki
Published: May 2006

Plasma oxidation of a titanium electrode above liquid water was investigated to reveal the interaction between metallic titanium and plasma above liquid water. Dc‐plasma was generated between the titanium and water electrodes. When the titanium electrode was set as anodal, a thick rutile layer was formed on the surface. We had reported previously that the layer showed the preferred orientation along 〈110〉normal to the surface. The degree of the preferred orientation showed a maximum of 0.8 at the electrode temperature of 1073 K. When the titanium electrode was set as cathodal, a plume was generated with the temperature rise because of the bombarding effect of cationic species in the plasma. The collected particles were spherical and were identified as anatase with a small amount of rutile. Optical emission spectroscopy suggested that an oxide layer (TiO2) firstly formed on the Ti cathode surface, and then vaporization took place with the temperature rise. The spherical anatase particles were formed from the TiO2 vapor through the rapid cooling.
Trap Levels in Eu‐Doped SrAl2O4 Phosphor Crystals Co‐Doped with Rare‐Earth Elements
Authors: Katsumata T. , Toyomane S. , Sakai R. , Komuro S. , Morikawa T.
Published: May 2006

SrAl2O4:Eu2+ phosphor crystals co‐doped with auxiliary activators such as La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, or Y have been grown by the floating zone (FZ) technique. Photoluminescence spectrum (PL), time‐resolved PL, and thermally stimulated luminescence (TSL) are evaluated to clarify the long‐duration phosphorescence mechanism of SrAl2O4, Eu, and Ln phosphors. TSL spectra were measured in the temperature range from RT to 600 K to evaluate the depth and densities of the traps generated by the doping of auxiliary activators that are responsible for the long‐duration phosphorescence. The peak wavelength of PL does not vary with auxiliary activator elements, while decay curves vary greatly with the auxiliary activators. The trap depth and the densities of the trapped carriers estimated based on the hole trap model also vary with the auxiliary activator elements. The traps generated at around E=0.5 eV by the auxiliary activators, Nd, Dy, and Tm, with sufficient densities are effective for the long‐duration phosphorescence.
Injury incidence, mechanism and diagnosis in top‐level teamgym: a prospective study conducted over one season
Authors: Harringe M. L. , Renström P. , Werner S.
Published: May 2006

The aim of this study was to evaluate injury incidence, mechanism and diagnosis in Swedish teamgym. Sixteen male and 26 female gymnasts with international experience were prospectively followed during one season of training and competition. Injuries leading to a modified participation or total absence from gymnastics during 1 week or more were registered. Twenty‐seven of the 42 gymnasts sustained 42 injuries. The injury incidence was 2.2/1000 gymnastics hours. No gender differences were found. Sixty‐two percent of the injuries were located to the lower extremity, 28.5% to the back and 9.5% to the upper extremity. The most common injury was ankle sprain and the most frequent mechanisms were joint compression and joint rotation. The majority of the injuries occurred in the landing phase of the gymnastics skills and 50% of the injuries were reported at the end of the training session. Eighteen injuries occurred while the gymnasts were in a negative state of mood such as stressed or afraid. Injury prevention programs should be developed with respect to these findings. Special emphasis must be placed on the landing phase of the gymnastics skills as this phase seems to be critical.
Long‐term changes in ground water chemistry at a phytoremediation demonstration site
Authors: Eberts Sandra M. , Jones Sonya A. , Braun Christopher L. , Harvey Gregory J.
Published: May 2006

A field‐scale demonstration project was conducted to evaluate the capability of eastern cottonwood trees (Populus deltoides) to attenuate trichloroethene (TCE) contamination of ground water. By the middle of the sixth growing season, trees planted where depth to water was <3 m delivered enough dissolved organic carbon to the underlying aquifer to lower dissolved oxygen concentrations, to create iron‐reducing conditions along the plume centerline and sulfate‐reducing or methanogenic conditions in localized areas, and to initiate in situ reductive dechlorination of TCE. Apparent biodegradation rate constants for TCE along the centerline of the plume beneath the phytoremediation system increased from 0.0002/d to 0.02/d during the first six growing seasons. The corresponding increase in natural attenuation capacity of the aquifer along the plume centerline, from 0.0004/m to 0.024/m, is associated with a potential decrease in plume‐stabilization distance from 9680 to 160 m. Demonstration results provide insight into the amount of vegetation and time that may be needed to achieve cleanup objectives at the field scale.
Cholesterol modulates the volume-regulated anion current in Ehrlich-Lettre ascites cells via effects on Rho and F-actin
Authors: Klausen Thomas Kjær , Hougaard Charlotte , Hoffmann Else K. , Pedersen Stine F.
Published: May 2006

The mechanisms controlling the volume-regulated anion current (VRAC) are incompletely elucidated. Here, we investigate the modulation of VRAC by cellular cholesterol and the potential involvement of F-actin, Rho, Rho kinase, and phosphatidylinositol-(4,5)-bisphosphate [PtdIns(4,5)P2] in this process. In Ehrlich-Lettre ascites (ELA) cells, a current with biophysical and pharmacological properties characteristic of VRAC was activated by hypotonic swelling. A 44% increase in cellular cholesterol content had no detectable effects on F-actin organization or VRAC activity. A 47% reduction in cellular cholesterol content increased cortical and stress fiber-associated F-actin content in swollen cells. Cholesterol depletion increased VRAC activation rate and maximal current after a modest (15%), but not after a severe (36%) reduction in extracellular osmolarity. The cholesterol depletion-induced increase in maximal VRAC current was prevented by F-actin disruption using latrunculin B (LB), while the current activation rate was unaffected by LB, but dependent on Rho kinase. Rho activity was decreased by ∼20% in modestly, and ∼50% in severely swollen cells. In modestly swollen cells, this reduction was prevented by cholesterol depletion, which also increased isotonic Rho activity. Thrombin, which stimulates Rho and causes actin polymerization, potentiated VRAC in modestly swollen cells. VRAC activity was unaffected by inclusion of a water-soluble PtdIns(4,5)P2 analogue or a PtdIns(4,5)P2-blocking antibody in the pipette, or neomycin treatment to sequester PtdIns(4,5)P2. It is suggested that in ELA cells, F-actin and Rho-Rho kinase modulate VRAC magnitude and activation rate, respectively, and that cholesterol depletion potentiates VRAC at least in part by preventing the hypotonicity-induced decrease in Rho activity and eliciting actin polymerization.
Scanning Mutagenesis Reveals a Role for Serine 189 of the Heterotrimeric G-Protein Beta 1 Subunit in the Inhibition of N-Type Calcium Channels
Authors: Tedford H. William , Kisilevsky Alexandra E. , Peloquin Jean B. , Zamponi Gerald W.
Published: May 2006

Direct interactions between the presynaptic N-type calcium channel and the β subunit of the heterotrimeric G-protein complex cause voltage-dependent inhibition of N-type channel activity, crucially influencing neurotransmitter release and contributing to analgesia caused by opioid drugs. Previous work using chimeras of the G-protein β subtypes Gβ1 and Gβ5 identified two 20–amino acid stretches of structurally contiguous residues on the Gβ1 subunit as critical for inhibition of the N-type channel. To identify key modulation determinants within these two structural regions, we performed scanning mutagenesis in which individual residues of the Gβ1 subunit were replaced by corresponding Gβ5 residues. Our results show that Gβ1 residue Ser189 is critical for N-type calcium channel modulation, whereas none of the other Gβ1 mutations caused statistically significant effects on the ability of Gβ1 to inhibit N-type channels. Structural modeling shows residue 189 is surface exposed, consistent with the idea that it may form a direct contact with the N-type calcium channel α1 subunit during binding interactions.
Web-based climate information resources for malaria control in Africa
Authors: Grover-Kopec Emily K , Blumenthal M Benno , Ceccato Pietro , Dinku Tufa , Omumbo Judy A , Connor Stephen J
Published: May 2006

Malaria remains a major public health threat to more than 600 million Africans and its control is recognized as critical to achieving the Millennium Development Goals. The greatest burden of malaria in Africa occurs in the endemic regions where the disease pathogen is continuously present in the community. These regions are characterized by an environment that is conducive to interactions between the Anopheles mosquito, malaria parasites and human hosts, as well as housing of generally poor quality, which offers little protection from mosquito-human contact. Epidemic malaria tends to occur along the geographical margins of endemic regions, when the equilibrium between the human, parasite and mosquito vector populations is occasionally disturbed and a sharp but temporary increase in disease incidence results. When malaria control measures are inadequate, as is the case in much of sub-Saharan Africa, the disease distribution is closely linked with seasonal patterns of the climate and local environment. In the absence of good epidemiological data on malaria distribution in Africa, climate information has long been used to develop malaria risk maps that illustrate the boundaries of 'climatic suitability for endemic transmission.' The best known of these are produced by the Pan-African-based MARA Collaboration. This paper describes the development of additional malaria suitability maps which have been produced in an online, interactive format to enable temporal information (i.e., seasonality of climate conditions) to be queried and displayed along with spatial information. These maps and the seasonal information that they contain should be useful to the malaria control and health service communities for their planning and operational activities.
Distinct roles of Polycomb group gene products in transcriptionally repressed and active domains ofHoxb8
Authors: Fujimura Yu-ichi , Isono Kyo-ichi , Vidal Miguel , Endoh Mitsuhiro , Kajita Hiroshi , Mizutani-Koseki Yoko , Takihara Yoshihiro , van Lohuizen Maarten , Otte Arie , Jenuwein Thomas , Deschamps Jacqueline , Koseki Haruhiko
Published: May 2006

To address the molecular mechanisms underlying Polycomb group(PcG)-mediated repression of Hox gene expression, we have focused on the binding patterns of PcG gene products to the flanking regions of the Hoxb8 gene in expressing and non-expressing tissues. In parallel, we followed the distribution of histone marks of transcriptionally active H3 acetylated on lysine 9 (H3-K9) and methylated on lysine 4 (H3-K4), and of transcriptionally inactive chromatin trimethylated on lysine 27 (H3-K27). Chromatin immunoprecipitation revealed that the association of PcG proteins,and H3-K9 acetylation and H3-K27 trimethylation around Hoxb8 were distinct in tissues expressing and not expressing the gene. We show that developmental changes of these epigenetic marks temporally coincide with the misexpression of Hox genes in PcG mutants. Functional analyses, using mutant alleles impairing the PcG class 2 component Rnf2 or the Suz12mutation decreasing H3-K27 trimethylation, revealed that interactions between class 1 and class 2 PcG complexes, mediated by trimethylated H3-K27, play decisive roles in the maintenance of Hox gene repression outside their expression domain. Within the expression domains, class 2 PcG complexes appeared to maintain the transcriptionally active status via profound regulation of H3-K9 acetylation. The present study indicates distinct roles for class 2 PcG complexes in transcriptionally repressed and active domains of Hoxb8 gene.
Spatial Pattern Formation, Size Selection, and Directional Flow of Polymer Latex Particles by Laser Trapping Technique
Authors: Misawa Hiroaki , Koshioka Masanori , Sasaki Keiji , Kitamura Noboru , Masuhara Hiroshi
Published: May 2006

Polystyrene latex particles with the diameter of ≈1 μm in water were laser trapped in spatial images of a laser beam. For a mixture of latex particles with different diameters, delicate tuning of the images resulted in size selection of the particles. Directional flow of the particles in water was also achieved by laser irradiation.
The influence of the nature and textural properties of different supports on the thermal behavior of Keggin type heteropolyacids
Authors: Popa Alexandru , Sasca Viorel , Stefanescu Mircea , Kis Erne , Marinkovic-Neducin Radmila
Published: May 2006

In order to obtain highly dispersed heteropolyacids (HPAs) species, H3PMo12O40 and H4PVMo11O40 were supported on various supports: silica (Aerosil - Degussa and Romsil types) and TiO2. The structure and thermal decomposition of supported and unsupported HPAs were followed by different techniques (TGA-DTA, FTIR, XRD, low temperature nitrogen adsorption, scanning electron microscopy). All the supported HPAs were prepared by impregnation using the incipient wetness technique with a 1:1 mixture of water-ethanol. Samples were prepared with different concentrations to examine the effect of loading on the thermal behavior of the supported acid catalysts. The thermal stability was evaluated with reference to the bulk solid acids and mechanical mixtures. After deposition on silica types supports, an important decrease in thermal stability was observed on the Romsil types and a small decrease on the Aerosil type. The stability of the heteropolyacids supported on titania increased due to an anion-support interaction, as the thermal decomposition proceeded in two steps. The structure of the HPAs was not totally destroyed at 450 ?C as some IR bands were still preserved. A relatively uniform distribution of HPAs on the support surface was observed for all compositions of the active phase. No separate crystallites of solid phase HPAs were found in the SEM images.
The plane-to-cellular-to-dendrite transition of the shape of the crystallization front during the crystallization of Al-Cu alloys
Authors: Radojevic Vesna , Valcic Andreja , Nikolic Slobodanka , Golubovic Aleksandar
Published: May 2006

The evolution of the crystallization front from a planar to a dendritic one as a function of the G L/(Rc 0) parameter was investigated during the crystallization of Al-Cu alloys by the vertical Bridgman method. Six series of alloys with different initial compositions of Cu were solidified at different growth rates. A mathematical model for the heat transfer during vertical Bridgmen crystal growth was developed. The model was solved using the finite element method. The temperature gradient in the melt at the beginning of crystal growth was calculated using the obtained model. Discrete stages of the crystallization front were identified in the experiments, as the ratio G L/(Rc 0) decreased.
Covering properties of continua and mappings
Authors: Charatonik Janusz
Published: May 2006

It is known that monotone mappings preserve the covering property for continua Similar result is proved for having the covering property hereditarily. An example is constructed which shows that the two results cannot be extended to almost monotone mappings.
Symmetries of conservation laws
Authors: Konjik Sanja
Published: May 2006

We apply techniques of symmetry group analysis in solving two systems of conservation laws: a model of two strictly hyperbolic conservation laws and a zero pressure gas dynamics model, which both have no global solution, but whose solution consists of singular shock waves. We show that these shock waves are solutions in the sense of 1-strong association. Also, we compute all project able symmetry groups and show that they are 1-strongly associated, hence transform existing solutions in the sense of 1-strong association into other solutions.
A 2-dimensional algebraic variety with 27 rectilinear generators and 108 trisecants and its connection with the maximal exceptional simple lie group
Authors: Rosenfeld Boris
Published: May 2006

A 2-dimensional algebraic variety in 4-dimensional projective space determining a regular configuration is considered and its connection with simple exceptional Lie group E8 is found.
A Krasnoselskii cone compression result for multimaps in the S-KKM class
Authors: O`regan Donal , Shahzad Naseer , Agarwal Ravi
Published: May 2006

The aim of this article is obtain a Krasnoselskii cone compression theorem for multimaps in the class S-KKM.
Advanced TiAl6Nb7 Bone Screw Implant Fabricated by Metal Injection Moulding
Authors: Aust E. , Limberg W. , Gerling R. , Oger B. , Ebel T.
Published: May 2006

The innovative technology of metal injection moulding could be successfully applied to the titanium alloy TiAl6Nb7. For this reactive material the complex processing steps such as feedstock fabrication, injection moulding, debinding and sintering were optimised in the frame of the development of a bone screw implant.
Catalytic Polymer Membranes for high Temperature Hydrogenation of viscous Liquids
Authors: Fritsch D. , Bengtson G.
Published: May 2006

Polymeric membranes with high oil fluxes were developed and catalytically activated by a new route of direct calcination of polymeric membranes charged by Pd or Pt catalyst precursors. High concentrations of citric acid mixed with the precursors afforded a decrease of the calcination temperature to 175°C. Membrane reactor tests in the flow through contactor mode displayed high reactivities for sunflower oil hydrogenation. Pt showed a similar activity to Pd catalysts as measured by iodine value and generated about 13% less trans‐isomers but 5% more stearic acid at an iodine value of 90. By means of alumina supported catalysts tests of methyl oleate (cis‐C18:1) and methyl elaidate (trans‐C18:1) hydrogenation exhibited a different pathway of reaction by either isomerization followed by reduction (Pd) or primarily direct reduction to methyl stearate (Pt).
Synthesis, Shape‐Memory Functionality and Hydrolytical Degradation Studies on Polymer Networks from Poly(rac‐lactide)‐b‐poly(propylene oxide)‐b‐poly(rac‐lactide) dimethacrylates
Authors: Choi N.‐Y. , Kelch S. , Lendlein A.
Published: May 2006

Amorphous, hydrolytically degradable, multi‐phase block copolymer networks were obtained by photocrosslinking. The macrodimethacrylate precursors were prepared by ring‐opening polymerisation (ROP). The aim of this investigation to tailor the materials' elasticity in the temporary shape could be achieved. Stress‐controlled, cyclic thermomechanical tensile experiments showed the materials' excellent shape‐memory properties with strain recovery rates up to 99 %. The presented amorphous, biodegradable polymer network system with shape‐memory presents a new generation of multi‐functional biomaterials enabling applications in keyhole surgery or controlled drug release.
Simulation of Crack Growth in Al Panels Under Biaxial Loading
Authors: Scheider I. , Schödel M.
Published: May 2006

Safety and reliability are the most important issues in all engineering structures. In recent years the so‐called damage tolerance has become a main requirement. The assessment of cracked structures can be performed using analytical methods. Two models are presented in the paper: the cohesive model and the CTOA model.
Maximum likelihood estimators of population parameters from doubly left‐censored samples
Authors: Aboueissa Abou El‐Makarim A. , Stoline Michael R.
Published: May 2006

Left‐censored data often arise in environmental contexts with one or more detection limits, DLs. Estimators of the parameters are derived for left‐censored data having two detection limits: DL1and DL2assuming an underlying normal distribution. Two different approaches for calculating the maximum likelihood estimates (MLE) are given and examined. These methods also apply to lognormally distributed environmental data with two distinct detection limits. The performance of the new estimators is compared utilizing many simulated data sets. Examples are given illustrating the use of these methods utilizing a computer program given in the Appendix. Copyright © 2006 John Wiley & Sons, Ltd.
Forcing under Anti‐Foundation Axiom: An expression of the stalks
Authors: Kentaro Sato
Published: May 2006

We introduce a new simple way of defining the forcing method that works well in the usual setting under FA, the Foundation Axiom, and moreover works even under Aczel's AFA, the Anti‐Foundation Axiom. This new way allows us to have an intuition about what happens in defining the forcing relation. The main tool is H. Friedman's method of defining the extensional membership relation ∈ by means of the intensional membership relation ε .

Analogously to the usual forcing and the usual generic extension for FA‐models, we can justify the existence of generic filters and can obtain the Forcing Theorem and the Minimal Model Theorem with some modifications. These results are on the line of works to investigate whether model theory for AFA‐set theory can be developed in a similar way to that for FA‐set theory.

Aczel pointed out that the quotient of transition systems by the largest bisimulation and transition relations have the essentially same theory as the set theory with AFA. Therefore, we could hope that, by using our new method, some open problems about transition systems turn out to be consistent or independent. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Residuated logics based on strict triangular norms with an involutive negation
Authors: Cintula Petr , Klement Erich Peter , Mesiar Radko , Navara Mirko
Published: May 2006

In general, there is only one fuzzy logic in which the standard interpretation of the strong conjunction is a strict triangular norm, namely, the product logic. We study several equations which are satisfied by some strict t‐norms and their dual t‐conorms. Adding an involutive negation, these equations allow us to generate countably many logics based on strict t‐norms which are different from the product logic. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Categorical abstract algebraic logic: The largest theory system included in a theory family
Authors: Voutsadakis George
Published: May 2006

In this note, it is shown that, given a π ‐institution ℐ = 〈Sign, SEN, C 〉, with N a category of natural transformations on SEN, every theory family T of ℐ includes a unique largest theory system $ \overleftarrow T $ of ℐ. $ \overleftarrow T $ satisfies the important property that its N ‐Leibniz congruence system always includes that of T . As a consequence, it is shown, on the one hand, that the relation ΩN ($ \overleftarrow T $) = ΩN (T ) characterizes N ‐protoalgebraicity inside the class of N ‐prealgebraic π ‐institutions and, on the other, that all N ‐Leibniz theory families associated with theory families of a protoalgebraic π ‐institution ℐ are in fact N ‐Leibniz theory systems. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A probabilistic approach to quantum mechanics based on ‘tomograms’
Authors: Caponigro M. , Mancini S. , Man'ko V.I.
Published: May 2006

It is usually believed that a picture of Quantum Mechanics in terms of true probabilities cannot be given due to the uncertainty relations. Here we discuss a tomographic approach to quantum states that leads to a probability representation of quantum states. This can be regarded as a classical‐like formulation of quantum mechanics which avoids the counterintuitive concepts of wave function and density operator. The relevant concepts of quantum mechanics are then reconsidered and the epistemological implications of such approach discussed.
GaN‐based Schottky diodes for hydrogen sensing in transformer oil
Authors: Sandvik Peter , Babes‐Dornea Elena , Roy Trudel Anik , Georgescu Marius , Tilak Vinayak , Renaud Daniel
Published: May 2006

We report the demonstration of robust, GaN‐based hydrogen sensors for use directly in transformer oil. These 1 mm2 Schottky diodes were immersed in a closed loop with Voltesso insulating oil for 21 months of continuous testing. They showed good reproducibility in response to hydrogen gases, while exposed to varying temperatures. We will briefly discuss the transformer monitoring application, the device design and fabrication process, and the sensor performance from 21‐months of testing. Transfer functions from oil temperature and dissolved gas concentration have been quantified, and those will be briefly discussed. These new sensors offer a novel alternative to electrochemical cell‐based sensors for various applications. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Narrow‐band 400 nm MSM photodetectors using a thin InGaN layer on a GaN/sapphire structure
Authors: Ohsawa J. , Kozawa T. , Fujishima O. , Itoh H.
Published: May 2006

Dark‐ and photo‐current characteristics, spectral responsivity, and temporal response to a short optical pulse are compared for two devices with the In0.12Ga0.88N thickness of 20 nm and 50 nm. The detecting area is a square of 1 mm × 1 mm or 0.5 mm × 0.5 mm to be applied for plastic optical fibers with large core diameters. Both devices showed narrow‐band responsivity in the wavelength range of 360‐425 nm. The 20‐nm device is satisfactory in the dark‐ and photo‐current characteristics. While, increased currents were observed for 50‐nm device, which fact is attributed to an incoherent growth of the thicker layer on GaN. Pulse responses in the range of nanosecond were measured. But the high‐speed response is weaker than that of the DC operation. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Chemometrics and its applications to x‐ray spectrometry
Authors: Luo Liqiang
Published: May 2006

Recent developments in curve fitting, multivariate calibration, and pattern recognition in chemometrics, and their application to x‐ray spectrometry, are reviewed. Relatively innovated algorithms, namely genetic algorithms, neural networks and support vector machines, are discussed. Together with the three algorithms, the performances of different algorithms are compared briefly, which mainly includes principal component analysis, partial least‐squares regression, factor analysis, cluster analysis, nearest neighbor methods, linear discriminant analysis, linear learning machine, and soft independent modeling of class analogy. In general, the chemometrics methods are superior to the conventional methods, such as Fourier transform and Marquardt–Levenberg algorithms, to a certain extent. Copyright © 2006 John Wiley & Sons, Ltd.
A history of modern treatment of aortic aneurysms
Authors: Shumacker Harris B
Published: May 2006

The history of the modern treatment of aortic aneurysms is briefly reviewed, especially with reference to developments of particular interest because of improvements they brought about, controversies they initiated, and new directions they indicated as worth following. Lesions treated with considerable risk not long ago or considered operatively unmanageable are being operated upon with progressively greater safety and better results. To be sure, there are certain matters concerning which divergent opinions are held, and these debatable issues can only be resolved with further experiences. The progress which has been made foretells continued improvement in the future.
An update of treatment of aneurysms of the descending thoracic aorta
Authors: Najafi Hassan , Javid Hushang , Hunter James A. , Serry Cyrus , Monson David O.
Published: May 2006

Excisional therapy has been employed in 32 patients with fusiform aneurysms of the descending aorta. Based on the addition of one of the bypass techniques employed to minimize the hemodynamic abnormalities of aortic clamping, the series is divided into 2 groups, each comprised of 16 patients. In Group I either extracorporeal circulation or indwelling temporary shunts were employed during the period of aortic occlusion, while in Group II simple aortic cross‐clamping was utilized to manage the lesion. No adjuncts were used to avoid ischemia in the latter group. The only death and 2 instances of paraplegia occurred in the shunt group. In general, there were fewer complications in the no‐shunt group, with approximately 2/3 of the patients experiencing an uncomplicated postoperative course. These differences are considered significant, since the 2 groups were similar in respect to the extent and nature of the lesions and other factors influencing operative risk.
A formal relationship between program slicing and partial evaluation
Authors: Binkley David W. , Danicic Sebastian , Harman Mark , Howroyd John , Ouarbya Lahcen
Published: May 2006

A formal relationship between program slicing and partial evaluation is established. It is proved that for terminating programs, a residual program produced by partial evaluation is semantically equivalent to a conditioned slice.