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El rápido crecimiento de la producción de biodiésel ha disparado la disponibilidad de abundantes cantidades de glicerol con un potencial para su transformación en valiosos productos químicos e intermedios. La capacidad de los catalizadores homogéneos para acelerar la producción de biodiésel utilizando condiciones de reacción suaves es bien conocida y ha dado lugar a su uso generalizado. Sin embargo, los catalizadores homogéneos son miscibles en el medio de reacción, lo que ha provocado muchas preocupaciones relacionadas con su recuperación, reutilización y la generación de emulsiones, que redujeron el rendimiento así como la pureza del biodiésel y del glicerol. La catálisis heterogénea ha ofrecido una solución imperativa a los inconvenientes antes mencionados relacionados con el uso de sus homólogos homogéneos En el presente trabajo se ha optimizado un proceso de producción de biodiésel usando un nuevo catalizador heterogéneo a base de óxido de calcio enriquecido con glicerol. La eficacia del catalizador sintetizado para la metanólisis de aceite crudo de Jatropha curcas con alto contenido en ácidos grasos libres se investigó sistemáticamente examinando los efectos de la dosis de glicerol, la temperatura, el tiempo, la relación molar metanol-aceite y la cantidad de óxido de calcio (CaO) en el proceso. El índice de acidez del aceite se redujo 49 veces y la conversión máxima del aceite fue del 96,1% tras la reacción de metanólisis, lo que indicaba la mejora del rendimiento del óxido de calcio, tras su tratamiento con glicerol, en la aceleración de la producción de biodiésel a partir de aceite crudo con una cantidad muy elevada de ácidos grasos libres. Además, mediante el análisis de regresión (metodología de superficie de respuesta) se determinó la interacción entre las variables de reacción, su influencia en la metanólisis y las condiciones óptimas que afectan al proceso. El análisis estadístico sugirió que tanto la cantidad de CaO como la relación molar metanol/aceit, the Norwegian University of Life Sciences (Project No. 1301051406), Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

Antibodies are widely employed as biorecognition elements for the detection of a plethora of compounds including food and environmental contaminants, biomarkers, or illicit drugs. They are also applied in therapeutics for the treatment of several disorders. Recent recommendations from the EU on animal protection and the replacement of animal-derived antibodies by non-animal-derived ones have raised a great controversy in the scientific community. The application of recombinant antibodies is expected to achieve a high growth rate in the years to come thanks to their versatility and beneficial characteristics in comparison to monoclonal and polyclonal antibodies, such as stability in harsh conditions, small size, relatively low production costs, and batch-to-batch reproducibility. This review describes the characteristics, advantages, and disadvantages of recombinant antibodies including antigen-binding fragments (Fab), single-chain fragment variable (scFv), and single-domain antibodies (VHH) and their application in food analysis with especial emphasis on the analysis of biotoxins, antibiotics, pesticides, and foodborne pathogens. Although the wide application of recombinant antibodies has been hampered by a number of challenges, this review demonstrates their potential for the sensitive, selective, and rapid detection of food contaminants., FEDER funds from the AES-ISCIII program to R. B., Depto. de Química Analítica, Fac. de Ciencias Químicas, FALSE, pub

We give estimates for the measure of non-compactness of an operator interpolated by the limiting methods involving slowly varying functions. As applications we establish estimates for the measure of non-compactness of operators acting between Lorentz–Karamata spaces., Depto. de Análisis Matemático y Matemática Aplicada, Fac. de Ciencias Matemáticas, TRUE, pub

We investigate how environmental and trade policies affect the transfer of environmental technology in a two-country model with global pollution. By comparing free trade and tariff policy with or without commitment, the following results are obtained. First, firms avoid the implementation of environmental tax by contracting technological transfer. Second, there is a case in which free trade is preferable to a tariff policy for both countries when there is no commitment to a tariff level. Third, free trade is not Pareto-preferred to a tariff policy when there is a commitment.

The influence of crystal thickness of metal-coated <100>-cut GaAs (M-G-M) onCherenkov-phase-matched terahertz (THz) pulse detection was studied. The M-G-M detectors were utilized in conjunction with a metallic tapered parallel-plate waveguide (TPPWG). Polarization-sensitive measurements were carried out to exemplify the efficacy of GaAs in detecting transverse magnetic (TM)- and transverse electric (TE)-polarized THz waves. The reduction of GaAs’ thickness increased the THz amplitude spectra of the detected TMpolarized THz electro-optic (EO) signal due to enhanced electric field associated with a more tightly-focused and well-concentrated THz radiation on the thinner M-G-M. The higherfluence THz beam coupled to the thinner M-G-M improved the integrated intensity of the detected THz amplitude spectrum. This trend was not observed for TE-polarized THz waves, wherein the integrated intensities were almost comparable. Nevertheless, good agreement of spectral line shapes of the superposed TM- and TE-polarized THz-EO signals with that of elliptically polarized THz-EO signal demonstrates excellent polarization-resolved detection capabilities of M-G-M via Cherenkov-phase-matched EO sampling technique.

Although visual and auditory inputs are initially processed in separate perception systems, studies have built on the idea that to maintain spatial information these modalities share a component of working memory. The present study used working memory navigation tasks to examine functional similarities and dissimilarities in the performance of updating tasks. Participants mentally updated the spatial location of a target in a virtual array in response to sequential pictorial and sonant directional cues before identifying the target's final location. We predicted that if working memory representations are modality-specific, mixed-modality cues would demonstrate a cost of modality switching relative to unimodal cues. The results indicate that updating performance using visual unimodal cues positively correlated with that using auditory unimodal cues. Task performance using unimodal cues was comparable to that using mixed modality cues. The results of a subsequent experiment involving updating of target traces were consistent with those of the preceding experiments and support the view of modality-nonspecific memory.

Atmospheric Chemistry Modeling and Analysis Program (ACMAP) NASA, The dynamical variability of the boreal stratospheric polar vortex has been usually analysed considering the extended winter as a whole or only focusing on December, January and February. Yet recent studies have found intra-seasonal differences in the boreal stratospheric dynamics. In this study, the intra-seasonal variability of anomalous wave activity preceding polar vortex extremes in the Northern Hemisphere is examined using ERA-Interim reanalysis data. Weak (WPV) and strong (SPV) polar vortex events are grouped into early, mid- or late winter sub-periods depending on the onset date. Overall, the strongest (weakest) wave-activity anomalies preceding polar vortex extremes are found in mid- (early) winter. Most of WPV (SPV) events in early winter occur under the influence of east (west) phase of the Quasi-Biennial Oscillation (QBO) and an enhancement (inhibition) of wavenumber-1 wave activity (WN1). Mid- and late winter WPV events are preceded by a strong vortex and an enhancement of WN1 and WN2, but the spatial structure of the anomalous wave activity and the phase of the QBO are different. Prior to mid-winter WPVs the enhancement of WN2 is related to the predominance of La Nia and linked to blockings over Siberia. Mid-winter SPV events show a negative phase of the Pacific-North America pattern that inhibits WN1 injected into the stratosphere. This study suggests that dynamical features preceding extreme polar vortex events in mid-winter should not be generalized to other winter sub-periods., Ministerio de Economia y Competitividad (España), Natural Environment Research Council (UK), National Aeronautics and Space Administration (US), Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

An 18-year-old girl presented with abdominal pain and a tumor was subsequently detected in the jejunum. We therefore carried out a wedge resection of the jejunum. The diagnosis of GIST was confirmed histologically, and a mutation in exon 9 of the c-kit gene was observed. GISTs are rare in pediatric populations and pediatric GISTs occur predominantly in females and are characterized by a multifocal gastric location and a wild-type phenotype for the c-kit genes. The features of pediatric GISTs of the small intestine have not yet been categorized, and to date, only 11 cases in patients younger than 18 years have been reported. These cases did not occur primarily in females and tended to present as single tumors with mutations in the c-kit gene. This suggests that these cases do not have the same features as pediatric gastric GISTs, but instead are similar to adult GISTs.

We investigated the regulation of the pharyngeal and upper esophageal reflexes during swallowing in eel. By retrograde tracing from the muscles, the motoneurons of the upper esophageal sphincter (UES) were located caudally within the mid-region of the glossopharyngeal-vagal motor complex (mGVC). In contrast, the motoneurons innervating the pharyngeal wall were localized medially within mGVC. Sensory pharyngeal fibers in the vagal nerve terminated in the caudal region of the viscerosensory column (cVSC). Using the isolated brain, we recorded 51 spontaneously active neurons within mGVC. These neurons could be divided into rhythmically (n = 8) and continuously (n = 43) firing units. The rhythmically firing neurons seemed to be restricted medially, whereas the continuously firing neurons were found caudally within mGVC. The rhythmically firing neurons were activated by the stimulation of the cVSC. In contrast, the stimulation of the cVSC inhibited firing of most, but not all the continuously firing neurons. The inhibitory effect was blocked by prazosin in 17 out of 38 neurons. Yohimbine also blocked the cVSC-induced inhibition in five of prazosin-sensitive neurons. We suggest that the neurons in cVSC inhibit the continuously firing motoneurons to relax the UES and stimulate the rhythmically firing neurons to constrict the pharynx simultaneously.

Background: Cell therapy using autologous cells has been used in the treatment of various medical conditions. The mononuclear cell (MNC) fraction of bone marrow (BM) contains stem/progenitor cells that could contribute to osteogenesis and angiogenesis. Questions/purposes: We asked whether MNCs derived from intraoperative shed blood (SB), consisting of peripheral blood and BM, have osteoinductive and angiogenic potential. Methods: We harvested SB and BM from six patients undergoing THA. Isolated MNCs from SB and BM were analyzed by flow cytometry to evaluate the CD34+ cell fraction and 1 × 106 cells were seeded on an interconnective porous calcium hydroxyapatite ceramic (IP-CHA) and transplanted in the backs of athymic rats. IP-CHAs without cells were transplanted as controls and all composites were harvested after 4 and 8 weeks. Osteoinductive potential was evaluated by histologic observation, immunohistochemistry, and enzyme-linked immunosorbent assay (ELISA) using anti-osteocalcin (OC) antibodies qualitatively and quantitatively. To evaluate angiogenic potential, capillary density was measured by immunohistochemistry using Isolectin B4 4 weeks after implantation. Results: We found that CD34+ cells existed in SB-MNCs and there was a trend toward lower frequency compared with BM-MNCs. Histologic osteoinduction, OC expression, and capillary density were increased by transplantation of MNCs from SB. Similar results were achieved with MNCs from BM. Conclusions: MNCs from SB have equivalent osteoinductive and angiogenic potential compared with those from BM. Clinical Relevance: SB could be an attractive source for isolation of MNCs, enhancing osteoinduction and neovascularization, to augment the reconstruction of skeletal defects.

Mobile plaque is associated with increased risk of ischemic stroke, but definitions have remained unclear. We have previously reported that carotid ultrasonography can detect the mobile component of the carotid plaque surface, which rises and falls in a manner inconsistent with arterial pulsatile wall motion (Jellyfish sign). However, clinical and pathological features of Jellyfish sign remain unclear. The subjects comprised of 165 patients with carotid plaque and degree of area stenosis >= 50% on ultrasonography. Using magnetic resonance imaging, we quantified intraplaque hemorrhage (IPH) and defined ischemic stroke in each patient. Fifteen surgical specimens were obtained by carotid endarterectomy, and pathological features (area of fibrous cap and intraplaque atheromatous lesion) were compared with ultrasonographic plaque surface movement rate. Carotid plaques with IPH were seen in 78 cases, with Jellyfish sign in 31 cases. Jellyfish sign was not detected in patients without IPH. In these 15 patients, the fibrous cap covered the atheromatous lesion, and cap thickness correlated negatively with Jellyfish-positive plaque surface movement rate. Kaplan-Meier and Cox multiple regression analysis demonstrated that the most important predictor of ischemic stroke during follow-up is Jellyfish sign, not IPH. Stroke events in patients with Jellyfish sign repeated within a short interval after diagnosis. Jellyfish sign on ultrasonography is a sign of high-risk plaque vulnerability, suggesting rupture of the fibrous cap associated with the release of thrombogenic factors into the arterial lumen, and resulting in repeated ischemic stroke during a short interval after diagnosis.

[t-BuNSiMe2(3,6-t-Bu(2)Flu)]TiMe2 (1) combined with trialkylaluminum-free modified methylaluminoxane (dMMAO) was used to induce the living polymerization of propylene in toluene at -20, 0, and 25 degrees C with control of the syndiospecificity. After the first polymerization at -20 degrees C, the same amounts of propylene were added at 25 degrees C for the second polymerization. The resulting PP was syndiotactic-rich (rr = 0.75), the value of which is the arithmetical average ((0.89 + 0.60)/2 = 0.745) of those produced at -20 and 25 degrees C. These results indicate the formation of the expected syndiotactic-atactic di-stereoblock PP.

We investigate lepton flavor violating (LFV) radiative processes and the relic abundance of neutralino dark matter in supersymmetric type-I seesaw model. We carefully derive threshold corrections to the flavor off-diagonal elements of slepton mass matrix and up-type Higgs mass squared and find that they can be large in the case of large B-N(0). We examine how the branching ratios of LFV radiative decays and the relic abundance of neutralino dark matter can be significantly affected by the large threshold corrections. Soft scalar mass squared parameter of up-type Higgs scalar is also affected by the threshold corrections. Since the higgsino mass depends on the mass parameter for up-type Higgs, the LFV processes and the relic abundance of the neutralino dark matter are correlated with each other. We show that there are parameter regions where the predictions of the relic abundance of neutralino dark matter are consistent with WMAP observation and the branching ratios of LFV radiative decays are predicted to be testable in future experiments. We find that the masses of scalar supersymmetric particles are not necessarily small so that the branching ratios of LFV decays can be testable in future experiment, which is distinctive feature of this scenario.

The present study investigated the effects of eccentric muscle contractions (ECC) on the content of myofibrillar proteins (my-proteins) and the catalytic activity of myofibrillar ATPase (my-ATPase) in skeletal muscles. Rat extensor digitorum longus and tibialis anterior muscles were exposed to 200-repeated ECC or isometric contractions (ISC) and used for measures of force output and for biochemical analyses, respectively. Whereas in ISC-treated muscles, full restoration of tetanic force was attained after 2 days of recovery, force developed by ECC-treated muscles remained depressed (P<0.05) after 6 days. The total my-protein content and the relative content of myosin heavy chain (MHC) in total my-proteins were unaltered during 4 days of recovery after ECC, but fell (P<0.05) to 55.9 and 63.4% after 6 days of recovery, respectively. my-ATPase activity expressed on a my-protein weight basis was unaltered immediately after ECC. However, it decreased (P<0.05) to 75.3, 45.3, and 49.3% after 2, 4 and 6 days of recovery, respectively. Total maximal calpain activity measured at 5 mM Ca2+ was significantly augmented (P<0.05) after 2 days of recovery, reaching a level of threefold higher after 6 days. These alterations were specific for ECC and not observed for ISC. These results suggest that depressions in my-ATPase activity contribute to ECC-induced decreases in force and power which can take a number of days to recover.

Load cells are used extensively in engineering fields. This paper describes a novel structural optimization method for single- and multi-axis load cell structures. First, we briefly explain the topology optimization method that uses the solid isotropic material with penalization (SIMP) method. Next, we clarify the mechanical requirements and design specifications of the single- and multi-axis load cell structures, which are formulated as an objective function. In the case of multi-axis load cell structures, a methodology based on singular value decomposition is used. The sensitivities of the objective function with respect to the design variables are then formulated. On the basis of these formulations, an optimization algorithm is constructed using finite element methods and the method of moving asymptotes (MMA). Finally, we examine the characteristics of the optimization formulations and the resultant optimal configurations. We confirm the usefulness of our proposed methodology for the optimization of single- and multi-axis load cell structures.

Phosphoprotein enriched in astrocytes 15 kDa (PEA-15) is a multifunctional protein that was first identified in brain astrocytes and that has subsequently been shown to be expressed in different tissues. Despite its many important roles, the clinical significance of PEA-15 expression levels in astrocytic tumors has yet to be properly defined. We studied the PEA-15 expression pattern of 65 patients [diagnosed according to World Health Organization (WHO) criteria] with diffuse astrocytoma (WHO grade II), anaplastic astrocytoma (grade III), and glioblastoma (grade IV). PEA-15 expression levels were immunohistochemically measured and categorized as no, low, or high expression. All tumors expressed PEA-15 in our study. Twenty-three (35.4%) and 42 (64.6%) tumors expressed low and high PEA-15 levels, respectively. In grade II astrocytoma (diffuse astrocytoma) and grade III astrocytoma (anaplastic astrocytoma), 100% and 88.9% of patients expressed high PEA-15 levels, respectively, while a smaller number (50%) of patients with grade IV astrocytoma (glioblastoma) expressed high PEA-15 levels. PEA-15 expression level was inversely associated with WHO grade (P = 0.0006). Next, we evaluated prognosis and PEA-15 expression levels in 43 patients with high-grade astrocytomas based on the following parameters: age, gender, WHO grade, surgical resection extent, MIB-1 labeling index (LI), and PEA-15 expression level. Multivariable analyses revealed that high PEA-15 expression level displayed a significant correlation with longer overall survival (OS) in high-grade astrocytomas (P = 0.0024). Patients with total resection survived significantly longer (P = 0.0044) than those with lower resection extent, while patients with MIB-1 labeling index a parts per thousand currency sign25% indicated significant (P = 0.0434) correlation with OS as well. In conclusion, PEA-15 expression level was inversely associated with WHO grade and may serve as an important prognostic factor for high-grade ast

A multiattribute utility function can be represented by a function of single-attribute utility functions if the decision maker's preference satisfies additive independence or mutually utility independence. Additive independence is a preference condition stronger than mutually utility independence, and the multiattribute utility function is in the additive form if the former condition is satisfied, otherwise it is in the multiplicative form. In this paper, we propose a method for sensitivity analysis of multiattribute utility functions in multiplicative form, taking into account the imprecision of the decision maker's judgment in the procedures for determining scaling constants (attribute weights).

This study evaluates an existing bus network from the perspectives of passengers, operators, and overall system efficiency using the output of a previously developed transportation network optimisation model. This model is formulated as a bi-level optimisation problem with a transit assignment model as the lower problem. The upper problem is also formulated as bi-level optimisation problem to minimise costs for both passengers and operators, making it possible to evaluate the effects of reducing operator cost against passenger cost. A case study based on demand data for Hiroshima City confirms that the current bus network is close to the Pareto front, if the total costs to both passengers and operators are adopted as objective functions. However, the sensitivity analysis with regard to the OD pattern fluctuation indicates that passenger and operator costs in the current network are not always close to the Pareto front. Finally, the results suggests that, regardless of OD pattern fluctuation, reducing operator costs will increase passenger cost and increase inequity in service levels among passengers.

Delayed pressure urticaria (DPU) is characterized by deep dermal wheals that appear in response to a local continuous pressure. Although it has been reported to complicate as many as 40% of cases of Caucasian patients with chronic urticaria, no definitive cases of Asian/Japanese patients have been reported in English literature. Here, we identified 17 cases of DPU, among 540 Japanese patients with urticaria (3.1%), based on careful history taking, pressure challenge test and, ideally, skin biopsy. Twelve out of 17 patients (70.5%) who undertook pressure challenge test developed wheal and erythema in the area of pressure 1-12 h later. Six out of 15 patients (40%) were positive for the autologous serum skin test. All cases were complicated with ordinary chronic urticaria, and all specimens of skin biopsies performed for 12 patients showed substantial eosinophil infiltration. All cases were resistant to antihistamines with or without other non-steroidal medications and eventually treated with 0.25-1.5 mg/day of betamethasone. However, 12 of them (70.6%) were able to cease steroid use because of cure or remission. For those cured or in remission, the duration of steroid administration and that from the onset to diagnosis was 11.2 +/- A 11.0 and 54.8 +/- A 60.2 months (mean +/- A SD), respectively. DPU may be identified as a relatively rare complication of Japanese patients with chronic idiopathic urticaria. A proper diagnosis and a small amount of steroid may be beneficial for the treatment of DPU.

To evaluate whether the pouchitis disease activity index (PDAI) alone is sufficient to select appropriate treatment plans for ulcerative colitis patients with bowel movement problems following ileal pouch-anal anastomosis (IPAA). The study included 70 patients undergoing an IPAA. For these patients, an evaluation by PDAI was performed prospectively at 1-2 years after the ileostomy closure. When the symptoms relevant to bowel movement appeared, PDAI was evaluated and metronidazole or ciprofloxacin was administered. Pouchitis was diagnosed in patients with PDAI scores of 7 or higher. The patients whose PDAI score was less than 7 and who responded to antibiotic therapy were defined as treatment responders having disease not diagnosed by PDAI (TR-NDPDAI). Pouchitis was diagnosed in 16 of the 70 enrolled patients (22.9%) using the PDAI scoring system. Of these 16 patients, 11 had acute pouchitis and 5 had chronic pouchitis. Twenty-one patients whose PDAI score was less than 7 were symptomatic. Among them, 12 were TR-NDPDAI. In patients with TR-NDPDAI, antibiotic treatment resulted in significant improvements in the PDAI score (P < 0.001) and in clinical symptoms (P < 0.001) after treatment. Antibiotic treatment was effective in a considerable number of ulcerative colitis patients whose PDAI score was less than 7 after IPAA.

With the existence of the social customs or norms, Naylor demonstrates a possibility of stable long-run equilibria of support for a strike in a labor market, and this implies that at least some individuals will behave cooperatively and hence the prisoners' dilemma could be escaped. In this paper, using an agent-based simulation model in which artificial adaptive agents have mechanisms of decision making and learning based on neural networks and genetic algorithms, we compare the results of our simulation analysis with that of the mathematical model by Naylor. In particular, while Naylor's model is based on rationality as it relates to individual utility maximization, agents behave adaptively in our agent-based simulation model; agents make decisions by trial and error, and they learn from experiences to make better decisions.

Twenty-six patients with anteroposterior (AP) laxity of the knee, associated with torn anterior cruciate ligament (ACL), were prospectively randomized for arthroscopic lower femoral tunnel placed single- or double-bundle reconstruction using hamstring tendons. We evaluated AP and rotational stabilities under regular loads (a 100-N anterior load and a 1.5-N m external–internal load) before and after ACL reconstruction, comparing single- and double-bundle reconstruction with our original device for applying quantitative tibial rotation and the navigation system intraoperatively. No significant differences were found between the two groups in AP displacement and total range of tibial rotation at 30° and 60° of knee flexion. We found that a lower femoral tunnel placed single-bundle reconstruction reproduced AP and rotational stability as well as double-bundle reconstruction after reconstruction intraoperatively.

ATP-based bioluminescence using mutant firefly luciferase was combined with an immunochromatographic lateral flow test strip assay for Salmonella enteritidis detection. In this combination method, the Salmonella-antibody-gold complex captured at the test line on the test strip was lysed by heat-treatment, and the ATP released from the cells was measured using mutant luciferase. This method resulted in approximately 1,000 times higher sensitivity in the detection of Salmonella (i.e. 10(3) c.f.u./ml) compared to immunochromatographic lateral flow assay.

Purpose We recently reported the sarcoma-selective antitumor effects of a newly developed nitrogen-containing bisphosphonate, minodronate (MIN), on malignant bone tumors. The aim of this study was to develop efficient combination MIN therapy in malignant bone tumors.Methods We examined downstream molecular events of MIN in osteosarcoma and Ewing's sarcoma cells to search for a partner to combine with MIN. Furthermore, we evaluated the combined effects of MIN and clinically available Doxorubicin (DOX).Results We found that MIN inhibited Rap 1A prenylation, and extracellular signal-regulated kinase (ERK) or Akt phosphorylation in osteosarcoma (Saos-2) and Ewing's sarcoma (SK-ES-1) cells. Interestingly, MIN activated p38 mitogen activated protein kinase (MAPK) only in SK-ES-1 cells and a p38 MAPK inhibitor augmented MIN-induced growth inhibition in SK-ES-1 cells. Doxorubicin (DOX) exerted synergistic effects on Saos-2 and SK-ES-1 cell lines. Daily injection of MIN enhanced the growth inhibition of SK-ES-1 xenograft sarcoma treated by DOX in nude mice.Conclusions These findings suggest that the inhibition of the p38 MAPK pathway may be attractive in overcoming cellular resistance against MIN. In the light of clinical settings, MIN may have a beneficial adjuvant role in the DOX treatment.

Adult Vanessa indica and Argyreus hyperbius frequently forage on flower nectar, but the former also utilizes tree sap and rotting fruits. Compared to flower nectar, these rotting foods are characterized by low sugar concentrations and the presence of fermentation products (ethanol and acetic acid). We suspected that gustatory responses by the receptors on the proboscis might differ in these species. Among the three sugars tested, sucrose elicited the greatest probing (behavioral) responses and was followed by fructose and glucose. A. hyperbius showed higher sugar sensitivity than V. indica in probing responsiveness. In electrophysiological responses of the proboscis sensilla, V. indica was slightly more sensitive than A. hyperbius to glucose and lower concentrations of the other sugars. The sugar reception in A. hyperbius was strongly inhibited by fermentation products, particularly acetic acid at natural concentrations. In contrast, V. indica was noticeably less susceptible to them than A. hyperbius, and its behavioral and sensory responses to sucrose were enhanced by 5–20% (w/v) ethanol. Thus, V. indica not only possesses tolerance to fermentation products but may perceive them as synergists for sugar reception. To utilize rotting foods, such tolerance might be more necessary than high sugar sensitivity.

The presence of large and massive segmental defects of the diaphyseal bone following tumor resection is a significant problem for orthopedic surgeons. Double or folded free vascularized fibula graft (FVFG) is used in massive femur defects and is considered to be a reliable reconstructive procedure. However, folded or double fibula grafts cannot prevent stress fractures. Here, a novel surgical procedure for bridging of massive femur defects using double FVFG and hydroxyapatite (HA) with autogenous bone grafts to prevent stress fractures is reported.

Lamellar mesostructured calcium phosphates constructed by ionic bonds were prepared by using n-alkylamines (n-C n H2n+1NH2, n = 8–18) at room temperature in the mixed solvent systems of aliphatic alcohol (C n H2n+1OH, n = 1–4) and water, and the synthetic conditions were investigated in detail. The mixed solvent systems suppressed the formation of crystalline calcium phosphates like brushite (CaHPO4·2H2O) and monetite (CaHPO4) at low temperatures, successfully affording pure lamellar mesostructured calcium phosphates. Other crystalline phases such as hydroxyapatite (Ca10(PO4)6(OH)2) were not formed under the conditions with the Ca/P molar ratios in the range of 0.7–1.0 in the starting mixtures. The Ca/P molar ratio of the lamellar mesostructured calcium phosphates was ca. 1.0, calculated by ICP and 31P MAS NMR data. Interestingly, the kind of alcohols strongly influenced the solubilities of calcium phosphate species and n-alkylamines, and then lamellar mesostructured phases were obtained with some morphological variation.

In repeated batch-wise thermophilic anaerobic digestion of dehydrated waste-activated sludge with 80% (w/w) water content (DWAS), although methane production reached 30 % of total organic carbon in DWAS in the first run of 15d, it gradually decreased and finally stopped in the subsequent runs together with an increase in ammonia concentration. When the loading of DWAS on anaerobic digestion was investigated, methane production at 30d significantly decreased with the increase in the amount of organic matter per kg wet sludge while enormous proportion of organic nitrogen in the DWAS was converted to ammonia within 5d. The addition of ammonia to sludge significantly decreased methane production rate. When ammonia was removed from the DWAS using a physicochemical method after 10d of ammonia production and it was applied to semi-continuous anaerobic digestion, stable methane production was observed.

A fluorescent red-shifted exciton-coupling chromophore, N,N'-Carbonyl-bridged dipyrrinone, was subjected to fluorescence-detected CD (FDCD) measurements as a primitive structure-elucidating probe with trans-1,2-cyclohexanediol template in several solvents under various instrumental conditions. With the help of a JASCO ellipsoidal mirror device FDCD465, a chloroform solution achieved the sensitivity enhancement by 50 times of the transmission CD and 5 times of the conventional FDCD. All FDCD spectra were completely free from the polarization artifacts.

A 76-year-old woman with pulmonary asbestosis was admitted with fever and polymyalgia. She subsequently developed a visual disorder, hemoptysis, and hemoperitoneum. A biopsy of the temporal artery revealed the presence of giant-cell arteritis. CT and angiography showed hemorrhaging from the bronchial and abdominal arteries. These observations suggested temporal arteritis in which medium-sized vessels were involved. This case implies the association between vasculitis and asbestosis, and suggests a problem in the classification of vasculitides.

Introduction An experimental canine model was used for quantitative histological study using bone morphometry and biomechanical study on impacted cancellous allografting with cement in revision total hip arthroplasty. Materials and methods The prosthesis had a collarless polished titanium alloy tapered stem with a head diameter of 15 mm. Twelve Beagle dogs were used. Cancellous bone grafts were obtained aseptically from the femoral condyles of other beagles. Histological examinations were performed up to 1 year after surgery. Biomechanical examinations were performed at 8 weeks after surgery. Results The new bone formation proceeded from the proximal part to the distal site of the femur in the long axis as well as from the host cortical bone to the cement layer. Bone morphometry showed that the mineral apposition rate was higher in the proximal site of the femur than in the distal site at 8 weeks after surgery, but no significant differences were observed at other times. The bone formation rate was higher in the proximal site of the femur at 8 weeks after surgery, while it increased in the distal site at 16 weeks postoperatively but had decreased at 1 year after surgery significantly. The load test at 8 weeks after surgery showed that there was no significant difference at all sites attached strain gauge between impacted cancellous allograft group and control group. Conclusion We concluded that biological replacement of the grafted bone by new bone settled at 1 year after surgery in this experimental model. However, the process was not completed.

The second order perturbation theory based on the locally projected molecular orbitals is devel- oped. A few test calculations with cc-pVDZ and aug-cc-pVDZ basis sets are carried out for the dimers, (H2O)2 and (HF)2. The charge transfer terms remove the de.ciency of the locally projected self-consistent .eld method for molecular interaction (LP SCF MO MI), and the potential energy curves calculated with aug-cc-pVDZ are very close to the corresponding curves of the counterpoise corrected SCF energy. Only after adding the spin-exchanged dispersion type to the dispersion and intra-molecular pair correlation terms, the calculated potential energy curves become close to those of the couterpoise corrected second order Moller-Plesset (MP2). Pragmatic approaches for reducing the in.uence of the basis set superposition error are proposed.

Purpose: The purpose of this study was to examine the long-term clinical results of meniscus transplantation for articular cartilage defects in the knee joint. Type of study: Case series. Method: From October 1990 to June 1995, 8 cases underwent allogenic or autogenic meniscus transplantations for articular cartilage defects, and 7 cases were available for follow-up evaluations. The age at surgery ranged from 14 to 42 years old (average 22.5). In one case, a transplantation of tissue-engineered cartilage was performed due to pain 5 years after surgery. The other 6 cases were followed up for 8 to 13 years (average 10.1). The size of the cartilage defect ranged from 1.0 cm2 to 6.3 cm2 (average 2.8cm2). Patients were evaluated with the Lysholm score and MR images. We also performed arthroscopic examinations in 3 cases at the final evaluation. Results: The Lysholm scores ranged from 76 points to 100 points. In MR images, the congruities between the grafted lesions and normal cartilage were evaluated as smooth surfaces in 4, slightly irregular surface in 1, irregular surface in 1, and one had disappeared. In arthroscopic findings at 11 years after surgery, the grafted meniscus could not be found in one knee that had severe osteoarthritis changes, and in the other knee the lesion of the transplanted meniscus resembled a flap tear. In another case, the grafted meniscus and the surrounding cartilage displayed irregular surfaces during transplantation of tissue-engineered cartilage. In histological findings, at 11 years after surgery a small lesion in the grafted area was not hyaline cartilage but fibrocartilage. Conclusions: This study leads us to the conclusion that meniscus transplantation for articular cartilage damage is not compared to ACI although two cases showed good clinical results for a short term but the tissue was remained fibrocartilage tissues for long term.. Level of Evidence: Level 4, case series.

An enoumously developed giant cheliped with the other small one characterizes the adult male fiddler crab. Some experiments with artificial severances of cheliped indicate that such a handedness in the cheliped size is maintained even after the regeneration of severed cheliped. On the other hand, some experimental researches give some results about an unknown physiological system which controls the emergence and the regeneration of the handedness in the cheliped size. In this paper, with two hypothesized factors relevant to the regeneration of a severed cheliped, we propose a simple mathematical model to describe the experimental result about the cheliped regeneration with a handedness after the cheliped severance for the fiddler crab. Our model gives a suggestion about an underlying system for the cheliped regeneration in the fiddler crab or some other crustacean species.

Dealuminated zeolites Y were treated with aqueous solutions of various acids and ammonium salts to investigate the realumination behavior under acidic conditions. From the results of 27Al MAS NMR, 29Si MAS NMR and FT-IR measurements, it was found that a part of non-framework aluminum species in the dealuminated zeolite Y is effectively reinserted into the zeolite framework in CHCOONHand CHCOONH34 654 aqueous solutions. Pyridine adsorption experiments also revealed that most of incorporated aluminum species generate tetrahedrally coordinated framework aluminum species, namely Brönsted acid sites. Although the realumination also proceeded in H2SO and CH43COOH aqueous solutions, large amounts of incorporated aluminum species were not necessarily responsible for generation of Brönsted acid sites. Framework connected aluminum species, presumably as 3-fold-coordinated Lewis acidic framework aluminum species, were mainly generated. In the TEM image of the realuminated zeolite Y, needle-like crystals with ca. 25-80 nm in length were observed, which are probably due to AlOOH generated from non-framework aluminum species.

A new methodology for the reliability optimization of a k dissimilar-unit non-repairable cold-standby redundant system is introduced in this paper. Each unit is composed of a number of independent components with generalized Erlang distributions of lifetimes arranged in a series-parallel configuration. We also propose an approximate technique to extend the model to the general types of non-constant hazard functions. To evaluate the system reliability, we apply shortest path technique in stochastic networks. The purchase cost of each component is assumed to be an increasing function of its expected lifetime. There are multiple component choices with different distribution parameters available for being replaced with each component of the system. The objective of the reliability optimization problem is to select the best components, from the set of available components, to be placed in the standby system in order to minimize the initial purchase cost of the system, maximize the system MTTF (mean time to failure), minimize the system VTTF (variance of time to failure) and also maximize the system reliability at the mission time. The goal attainment method is used to solve a discrete-time approximation of the original problem.

The Al distribution in high-silica MOR zeolites with various Si/Al ratios was investigated by FT-IR spectroscopy in the presence of CD3CN probe molecules and benzene adsorption. Two adsorption bands assigned to CN stretching vibration were observed at 2280-2295 and ≈ 2315 cm-1, which are due to interaction of CN with acidic hydroxyl groups in the main channels and the side pockets of H-MOR zeolite, respectively. The relative intensity of the peak at 2315 cm-1 increased with an increase in the Si/Al ratio, indicating that the proportion of Al atoms in the main channels relatively decreased with the Si/Al ratio. This was confirmed from the linear relationship between the number of benzene molecules adsorbed in a unit cell and the number of Al atoms in the main channels. In addition, this was also suggested from the computer simulation result that Al atoms are preferentially sitting in the T3 site.

A three-dimensional (3D) clinostat is a device for multidirectional G force generation. By controlled rotation of two axes, a 3D clinostat cancels the cumulative gravity vector at the center of the device and produces an environment with an average of 10^-3 G over time. We cultured a human osteoblast cell line in a 3D clinostat and examined the growth properties and differentiation of the cells, including morphology, histological detection of calcification, and mitogenactivated protein kinase (MAPK) cascades. In a normal 1G condition, alkaline phosphatase (AIPase) activity was detected on day 7 of culture, bone nodules were formed on day 12, and calcium deposits were seen on day 20. In the 3D clinostat, the cell looked larger and bulged. AIPase activity was detected on day 10 of culture. However, neither bone nodules nor calcification was found in the 3D clinostat up to day 21. The expression levels of core-binding factor A1 (a transcription factor for bone formation) and osteocalcin (a bone matrix protein) increased in the control culture but decreased in culture in 3D clinostat. Phosphorylation of p38^MARK (p38) was repressed in culture in 3D clinostat, whereas total p38 as well as total and phosphorylated forms of extracellular signal-regulated kinases and stress-activated protein kinase/jun N-terminal kinase were not changed in the 3D clinostat. When a p38 inhibitor, SB 203580, was added to the culture medium in a normal 1 G environment, AIPase activity and formation of bone nodules and calcium deposits were strongly inhibited. On the other hand, they were inhibited only partially by a MARK kinase inhibitor, U-0126. On the basis of these results, it is concluded that (1) osteoblast differentiation is inhibited in culture in a 3D clinostat and (2) this inhibition is mainly due to the suppression of p38 phophorylation.

Background Preoperative biliary drainage (PBD) is associated with bacterial contamination of bile, but the effects of PBD on morbidity after pancreatoduodenectomy remain controversial. The aim of this study was to characterize bile contamination to develop successful specific antibiotic prophylactic strategies for pancreatoduodenectomy. Methods Ninety-one consecutive patients who underwent pancreatoduodenectomy for periampullary tumor were prospectively evaluated. Prophylactic antibiotics were selected based on preoperative bile cultures. Bile cultures and postoperative complications were compared in 46 patients who underwent PBD (drainage group) versus 45 patients who did not (nondrainage group). Results The incidence of positive bile cultures was higher in the drainage group (78%) than in the nondrainage group (36%) (P < 0.001). In the drainage group, positive bile cultures were frequently polymicrobial (61%) and demonstrated resistance to several antibiotics, including cefazolin (83%), cefmetazole (72%), and cefpirome (64%). Overall morbidity (30-0x1.fd580000008p+0nd 22%) and infectious morbidity (13 0x1.f72676b636142p+855nd 11%) did not differ significantly between the drainage and nondrainage groups, respectively. Conclusions PBD had a notable influence on bile microbial contamination, including a higher rate of antibiotic resistance. Therefore, specific antibiotic prophylaxis based on bile culture is required for preventing infectious complications in pancreatoduodenectomy patients who undergo PBD.

The purpose of this study is, using a 16-section multidetector-row helical computed tomography (MDCT) scanner with retrospective reconstruction, to compare variability in repeated coronary calcium scoring and qualitative scores of the motion artifacts. One hundred forty-four patients underwent two subsequent scans using MDCT. According to Agatston and volume algorithms, the coronary calcium scores during mid-diastole (the center corresponding to 700f the R-R cycle) were calculated and the inter-scan variability was obtained. Motion artifacts from coronary artery calcium were subjectively evaluated and classified using a 5-point scale: 1, excellent; no motion artifacts; 2, fine, minor motion artifacts; 3, moderate, mild motion artifacts; 4, bad, severe motion artifacts; 5, poor, doubling or discontinuity. Each reading was done by vessels (left main, left descending, left circumflex and right coronary arteries) and the motion artifact score (mean of the scales) was determined per patient. The variability in the low (1.2±0.2) and high (2.4±0.6) motion artifact score groups was 7±6 (median, 6)-0x1.4aa00bfffbf7p-149nd 19±15 (16)26651131640n the Agatston score (P<0.01) and 7±7 (6)-0x1.f9a280852f11p+0nd 16±13 (14)26646061170n the volume score (P<0.01), respectively. In conclusion, motion has a significant impact on the reproducibility of coronary calcium scoring.

A potent and persistent non-mammalian derived vasodilator, maxadilan (Maxa) consists of 61 amino acids with two disulfide linkages and acts as an agonist of the type I receptor of pituitary adenylate cyclase activating polypeptide (PACAP), although there is very little sequence similarity. The total chemical syntheses of Maxa, its disulfide isomers and various fragments have been performed successfully by highly efficient solid-phase peptide synthesis (SPPS). A "difficult sequence", envisaged in the middle region of Maxa, could be overcome by improved synthesis protocols. After assembly peptides were liberated from the resin by cleavage. Peptides having disulfide(s) were purified by two steps of preparative HPLC using cation exchange followed by reverse phase columns. Purified peptides were characterized by HPLC, Edman-sequencing, amino acid analysis and mass spectrometry in addition to disulfide form determination. The peptides obtained were used for recognition studies by the melanophore assay to confirm the native disulfide form. Peptide libraries related to Maxa, produced in the present study, will be useful for the elucidation of the structural requirements of Maxa for interaction with the PACAP type 1 receptor (PAC1).

Objectives: To examine the effects of single-session, small-group stress management program on knowledge about stress, coping skills, and psychological and physical distress. Methods: A total of 300 employees from a company in western Japan were invited to participate in the study. Those who consented to enter the study were assigned to an intervention (n=149) or waiting list control group (n=151). Participants in the intervention group received a small-group stress management program. The program was primarily aimed at increasing knowledge about stress and improving coping skills. To investigate the intervention effect, change scores in outcome variables were calculated by subtracting the scores at pre-intervention from those at post-intervention (8 weeks after the pre-intervention survey). Next, the difference in the scores between groups was examined using analyses of covariance (ANCOVA) with the pre-intervention score as the covariate. Results: Favorable intervention effects were found on knowledge about stress and on coping skills (P < 0.001 and P=0.012, respectively) and adverse effects on psychological distress (P=0.022). However, this adverse effect on psychological distress did not exist among those who initially perceived higher levels of job control. Conclusion: The single-session stress management program was effective on improving knowledge about stress, and coping skills, where job control moderated the effect of the program on psychological distress.

Sine-wave modulated rf plasma has been used to control particle generation and growth in a plasma-enhanced chemical vapor deposition of silicon dioxide thin films using TEOS/O2. The density and the size of particles generated in the plasma are greatly reduced when the plasma is modulated with sine-wave modulation at low modulation frequency (<1000 Hz). In addition, particle contamination on the films is significantly reduced also for nanoparticles, and the film growth rates at the range of modulation frequencies where particle generation are greatly reduced do not decrease appreciably. Compared to its counterpart pulse-wave modulation plasma, the sine-wave modulation plasma has demonstrated a better performance in terms of reduction of particle generation and film contamination, and of film growth rate. Thus, the sine-wave modulation plasma has shown as a promising method to be applied in the production of thin film with a high deposition rate and a low particle contamination.

Background: The increase of serum IgE levels is closely associated with atopic dermatitis. We have previously revealed that cellular extract of PAM212 cells (PAM-extract), BALB/c mouse keratinocyte cell line, induced a remarkable increase of serum IgE levels, in vivo, when subcutaneously injected into BALB/c mice. However, precise mechanism of IgE-increasing activity was unclear. Objective: To elucidate the mechanism of IgE-increase in sera of BALB/c mice induced by PAM-extract, we explored the direct influence of PAM-extract on immunoglobulin production and class-switching in the culture of splenic lymphocytes and purified B-cells, in vitro. Methods: Splenic lymphocytes or purified B-cells obtained from BALB/c mice were cultured with various combinations of IL-4, anti-CD40 antibody, and PAM-extract for seven days. IgE and IgG concentrations of culture supernatants were measured by ELISA. Epsilon germ-line transcriptions were assessed by RT-PCR from the cultured cells. Results: IgE and IgG concentrations in culture supernatant of splenic lymphocytes were increased by an addition of PAM-extract in the presence of both IL-4 and anti-CD40 antibody. Epsilon germ-line transcript was also induced in parallel to the increase of IgE production. Similar results were obtained when purified B-cells were employed in stead of whole splenic lymphocytes. Conclusion: The cellular extract of keratinocyte promotes immunoglobulin class-switching to IgE and IgE production from mouse splenic B-cells in an IL-4- and CD40-stimuli-dependent manner. Such enhancement may account for the increase of serum IgE in patients with dermatitis in association with a Th2 microenvironment.

Moyamoya disease is a progressive occlusive disease of the circle of Willis with prominent collateral arterial formation. We report on a 12-year-old girl with moyamoya disease presenting with transient ischemic attacks (TIAs). Surgical indirect revascularization was performed. The patient did not suffer further TIAs at 12 month follow-up. Pre and postoperative cerebral perfusion were studied in quantitative single photon emission computerized tomography (SPECT) and CT perfusion imaging. CT perfusion imaging demonstrated postoperative increased cerebral blood flow as well as SPECT before and after revascularization. Furthermore, the area of decreased vascular reserve in SPECT with acetazolamide corresponded with areas of increased cerebral blood volume in CT perfusion imaging. CT perfusion imaging was equivalent to SPECT in accuracy, and superior in spatial resolution. CT perfusion imaging is likely to become more widely available as an easy-to-perform technique for assessing cerebral perfusion in a patient with moyamoya disease.

The present study was performed to examine whether there are functional differences between the first dorsal interosseous (FDI) and abductor digit minimi (ADM)muscles depending on different muscle contractions, dynamic and static contraction of index and little finger abduction. We recorded motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) and simultaneously recorded force curves during the muscle contractions. We also defined rest motor threshold (RMT) and active motor threshold (AMT, during dynamic and static contraction) in two muscles. F-waves were recorded in same procedures as MEPs. In all trials of MEP and F-wave, background EMGs (B.EMGs) were kept at same level. Force matching errors of dynamic contraction were statistically smaller in FDI muscle than those in ADM. In the FDI muscle, AMT during dynamic contraction was significantly lower than that during static one. Additionally, we employed MEP/B.EMG ratio as an index to assess functional differences between two muscles. In the FDI muscle, the ratios were larger during dynamic contraction than those during static ones. But such results were not found in the ADM muscle. F-waves remained steady in either muscle. Thus, we conclude that there are functional demanded excitability changes between FDI and ADM muscles, although they share the same innervations of ulnar nerve.

In our previous investigation on the genes of 1,5-bisphosphate carboxylase/oxygenase (RuBisCO; EC 4.1.1.39) in deep-sea chemoautotrophic and methanotrophic endosymbioses, the gene encoding the large subunit of RuBisCO form I (cbbL) had been detected in the gill of a mussel belonging to the genus Bathymodiolus from a western Pacific back-arc hydrothermal vent. This study further revealed the symbiont source of the RuBisCO cbbL gene along with the genes of 16S ribosomal RNA (16S rDNA), particulate methane monooxygenase (EC 1.14.13.25; pmoA) and ATP sulfurylase (EC 2.7.7.4; sopT). The 16S rDNA sequence analysis indicated that the mussel harbors a monospecific methanotrophic Gammaproteobacterium. This was confirmed by amplification and sequencing of the methanotrophic pmoA, while thiotrophic sopT was not amplified from the same symbiotic genome DNA. Fluorescence in situ hybridization demonstrated simultaneous occurrence of the symbiont-specific 16S rDNA, cbbL and pmoA, but not sopT, in the mussel gill. This is the first molecular and visual evidence for a methanotrophic bacterial endosymbiont that bears the RuBisCO cbbL gene relevant to autotrophic CO2 fixation.

Objective: The purpose of this study is to investigate how accurately we can measure CAC volume using electron beam computed tomography (CT) and 16-slice spiral CT. Materials and Methods: CAC models with known volume attached to a cardiac phantom were scanned. The error of measurement, variability between measured and real volumes and inter-scan measurement variability were obtained. For spiral CT, 7 different parameters; i.e. (1) slice-thickness (0.625mm, 1.25mm and 2.5mm), (2) retrospective spiral electrocardiograph (ECG)-gated or prospective axial ECG-triggering, (3) overlapping or non-overlapping, were included. Results: The error of measurement was 150n electron beam CT and 8-2027777735740n spiral CT. CAC volumes were underestimated in 92-0x1.4b3a0b6a4aap-149nd overestimated in 81024570420f the electron beam CT scans. Volumes were underestimated in 79%, correct in 5-0x1.86278bfffa1a8p-150nd overestimated in 1626651131640f the spiral CT scans. The best measurement and the least variability was observed on 0.625mm retrospective spiral ECG-gated CT (error of 8%), a significant result (t-test: p<0.01) when compared with electron beam CT. Conclusion: CAC volume measurement on CT scanners may be significantly different and often underestimates the real volume of CAC. For precise evaluation of CAC volume, thin-slice retrospective spiral ECG-gated scan using a spiral CT scanner is desirable.

A novel family of repetitive DNA sequences were molecularly cloned from ApaI-digested genomic DNA of two Galliformes species, Japanese quail (Coturnix japonica) and guinea fowl (Numida meleagris), and characterized by chromosome in-situ hybridization and filter hybridization. Both the repeated sequence elements produced intensely painted signals on the W chromosomes, whereas they weakly hybridized to whole chromosomal regions as interspersed-type repetitive sequences. The repeated elements of the two species had high similarity of nucleotide sequences, and cross-hybridized to chromosomes of two other Galliformes species, chicken (Gallus gallus) and blue-breasted quail (Coturnix chinensis). The nucleotide sequences were conserved in three other orders of Neognathous birds, the Strigiformes, Gruiformes and Falconiformes, but not in Palaeognathous birds, the Struthioniformes and Tinamiformes, indicating that the repeated sequence elements were amplified on the W chromosomes in the lineage of Neognathous birds after the common ancestor diverged into the Palaeognathae and Neognathae. They are components of the W heterochromatin in Neognathous birds, and a good molecular cytogenetic marker for estimating the phylogenetic relationships and for clarifying the origin of the sex chromosome heterochromatin and the process of sex chromosome differentiation in birds.