bluuebunny/crossref_metadata_2025_split huggingface dataset:
Temperature-dependent oxygen limitation in insect eggs
Authors: Woods H. Arthur , Hill Ryan I. 
Published: May 2004

SUMMARYMost terrestrial insect embryos support metabolism with oxygen from the environment by diffusion across the eggshell. Because metabolism is more temperature sensitive than diffusion, embryos should be relatively oxygen-limited at high temperatures. We tested whether survival, development time and metabolism of eggs of a moth, Manduca sexta, were sensitive to experimentally imposed variation in atmospheric oxygen availability(5–50 kPa; normoxia at sea level is 21 kPa) across a range of biologically realistic temperatures. Temperature–oxygen interactions were apparent in most experiments. Hypoxia affected survival more strongly at warmer temperatures. Metabolic rates, measured as rates of CO2emission, were virtually insensitive to hypo- and hyperoxia at 22°C but were strongly influenced at 37°C. Radial profiles of PO2 inside eggs, measured using an oxygen microelectrode, demonstrated that 3-day-old eggs had broad central volumes with PO2 less than 2 kPa, and that higher temperature led to lower PO2. These data indicate that at realistically high temperatures (32–37°C) eggs of M. sexta were oxygen limited, even in normoxia. This result has important implications for insect population ecology and the evolution of eggshell structures, and it suggests a novel hypothesis about insect gigantism during Paleozoic hyperoxia.
Dietary influences over proliferating cell nuclear antigen expression in the locust midgut
Authors: Zudaire E. , Simpson S. J. , Illa I. , Montuenga L. M. 
Published: May 2004

SUMMARYWe have studied the influence of variations in dietary protein (P) and digestible carbohydrate (C), the quantity of food eaten, and insect age during the fifth instar on the expression of the proliferating cell nuclear antigen(PCNA) in the epithelial cells of the midgut (with special reference to the midgut caeca) in the African migratory locust, Locusta migratoria. Densitometric analysis of PCNA-immunostained cells was used as an indirect measure of the levels of expression of PCNA, and a PCNA cellular index(PCNA-I) was obtained. Measurements of the DNA content of the cells have also been carried out by means of microdensitometry of Feulgen-stained, thick sections of midgut. A comparison between the PCNA nuclear level and the DNA content was performed. The PCNA levels were significantly different among the cells of the five regions studied: caeca, anterior ventricle, medial ventricle, posterior ventricle and ampullae of the Malpighian tubules. We have studied in more detail the region with highest PCNA-I, i.e. the caeca. The quality and the quantity of food eaten under ad libitum conditions were highly correlated with both the PCNA and DNA levels in the caeca cells. Locusts fed a diet with a close to optimal P:C content (P 21%, C 21%) showed the highest PCNA and DNA content. In locusts fed a food that also contained a 1:1 ratio of P to C but was diluted three-fold by addition of indigestible cellulose (P 7%, C 7%), a compensatory increase in consumption was critical to maintaining PCNA levels. Our measurements also showed that the nuclear DNA content of the mature and differentiated epithelial cells was several-fold higher than the levels in the undifferentiated stem cells of the regenerative nests. These results, combined with the low number of mitotic figures found in the regenerative nests of the caeca and the marked variation in PCNA levels among groups, suggest that some type of DNA endoreduplication process may be taking place. Our data also indicate that the DNA synthetic activity in the midgut is related to feeding in locusts. The possible dietary and nutritional regulatory mechanisms and the significance of the differences found are discussed.
Respiration rate of hepatocytes varies with body mass in birds
Authors: Else Paul L. , Brand M. D. , Turner N. , Hulbert A. J. 
Published: May 2004

SUMMARYHepatocytes were isolated from eight species of birds ranging from 13 g zebra finches to 35 kg emus. This represents a 2800-fold range of body mass(Mb). Liver mass (g) was allometrically related to species body mass by the equation: liver mass=19.6×Mb0.91. There was a significant allometric decline in hepatocyte respiration rate (HRR; nmol O2mg–1 dry mass min–1) with species body mass(kg) described by the relationship:HRR=5.27×Mb–0.10. The proportions of hepatocyte oxygen consumption devoted to (i) mitochondrial ATP production,(ii) mitochondrial proton leak and (iii) non-mitochondrial processes were estimated by using excess amounts of appropriate inhibitors. It was found that although hepatocyte respiration rate varied with body mass in birds, these processes constitute a relatively constant proportion of hepatocyte metabolic rate irrespective of the size of the bird species. The respective percentages were 54%, 21% and 25%. The portion of hepatocyte respiration devoted to ATP production for use by the sodium pump was estimated and found to be a relatively constant 24% of hepatocyte respiration and 45% of mitochondrial ATP production in different-sized bird species. These results are discussed in the context of competing theories to explain the metabolism–body size allometry, and are found to support the `allometric cascade' model.
Differences in the effects of salinity on larval growth and developmental programs of a freshwater and a euryhaline mosquito species (Insecta: Diptera,Culicidae)
Authors: Clark Thomas M. , Flis Benjamin J. , Remold Susanna K. 
Published: May 2004

SUMMARY
The effects of salinity on growth and development of the euryhaline Ochlerotatus taeniorhynchus and the freshwater Aedes aegyptiare compared. O. taeniorhynchus grow larger, and have greater intrinsic growth rates, than A. aegypti. Females of each species attain greater mass, take longer to develop, and have greater growth rates than do males. In O. taeniorhynchus, pupal mass, larval stage duration and growth rates (dry mass) increase with salinity, whereas growth rates (wet mass) remain constant across salinities, reflecting a decrease in percent body water. The pupal mass (wet or dry) of O. taeniorhynchusis determined primarily by effects of salinity on the rate of assimilation of dry mass, because the latter contributes very strongly to final pupal mass in both species. In contrast, the duration of A. aegypti larval stage follows a υ-shaped curve, with most rapid development at intermediate salinities. Growth rates of A. aegypti decrease with increasing salinity, and percent body water is constant across salinities. As for O. taeniorhynchus, duration of A. aegypti larval stage increases at high salinity. However, this increase in larval stage duration cannot compensate for the decrease in growth rate at high salinity, resulting in an overall decrease in both wet and dry pupal mass at high salinity. Thus,salinity has fundamentally different effects on developmental programs and phenotypic plasticity in the two species investigated.
Morphological plasticity varies with duration of infection: evidence from lactating and virgin wild-derived house mice (Mus musculus) infected with an intestinal parasite (Heligmosomoides polygyrus;Nematoda)
Authors: Kristan Deborah M. , Hammond Kimberly A. 
Published: May 2004

SUMMARY
With chronic parasite infection, host response to the parasite may change throughout the duration of the infection as the host progresses from the acute to the chronic phase. We investigated the effects of parasite infection ranging in duration from 30 to 120 days on host morphology both alone and in combination with lactation by using captive wild-derived house mice (Mus musculus) experimentally infected with a naturally occurring intestinal nematode (Heligmosomoides polygyrus). We found that some changes in host morphology were greatest at 30-60 days post-infection (e.g. spleen mass)followed by a decline towards the control state whereas other morphological changes were greatest at 90-120 days post-infection (e.g. small intestine mass) after a relatively steady increase with infection duration. For all infection durations, the morphological responses to parasite infection were similar for virgin and lactating mice (except for lean body mass). After accounting for changes in body mass with lactation, lactating mice increased organs of the gastrointestinal tract as well as liver and kidney but had less body fat than virgin mice. This is the first study to demonstrate that morphological plasticity of mice parasitized by H. polygyrus varies with infection duration and that this variation is generally similar for lactating and virgin mice.
Upper thermal tolerance and oxygen limitation in terrestrial arthropods
Authors: Klok C. Jaco , Sinclair Brent J. , Chown Steven L. 
Published: May 2004

SUMMARYThe hypothesis of oxygen limitation of thermal tolerance proposes that critical temperatures are set by a transition to anaerobic metabolism, and that upper and lower tolerances are therefore coupled. Moreover, this hypothesis has been dubbed a unifying general principle and extended from marine to terrestrial ectotherms. By contrast, in insects the upper and lower limits are decoupled, suggesting that the oxygen limitation hypothesis might not be as general as proposed. However, no direct tests of this hypothesis or its predictions have been undertaken in terrestrial species. We use a terrestrial isopod (Armadillidium vulgare) and a tenebrionid beetle(Gonocephalum simplex) to test the prediction that thermal tolerance should vary with oxygen partial pressure. Whilst in the isopod critical thermal maximum declined with declining oxygen concentration, this was not the case in the beetle. Efficient oxygen delivery via a tracheal system makes oxygen limitation of thermal tolerance, at a whole organism level,unlikely in insects. By contrast, oxygen limitation of thermal tolerances is expected to apply to species, like the isopod, in which the circulatory system contributes significantly to oxygen delivery. Because insects dominate terrestrial systems, oxygen limitation of thermal tolerance cannot be considered pervasive in this habitat, although it is a characteristic of marine species.
Codoped Rutile TiO2 as a New Photocatalyst for Visible Light Irradiation
Authors: Liu Hongyan , Gao Lian 
Published: May 2004

Abstract
(S, La2O3)-codoped rutile TiO2 was synthesized by in situ hydrothermal method. The (S, La2O3)-codoped rutile TiO2 treated at 200 °C exhibited the highest photocatalytic activities for degradation of methylene blue (MB) under visible light irradiation. The synergistic effects of S and a small quantity of La2O3 made the degradation rate of MB as high as 98.4%.
Fabrication and Degradation of Polyperoxides by a Radical Chain Process under Mild Conditions
Authors: Matsumoto Akikazu , Taketani Shuji 
Published: May 2004

Abstract
We have fabricated polyperoxides as new kinds of environment-friendly and degradable polymers using 1,3-diene compounds and oxygen as the starting comonomers under mild temperature and pressure conditions. They degrade in a radical chain mechanism by various stimuli; for example, degradation induced by physical (heating or irradiation), chemical (redox), and biochemical (enzymatic) stimuli.
Determination of Silica Mesophases by Controlling Silicate Condensation in Liquid Phase
Authors: Ogura Masaru , Suzuki Yushi , Miyoshi Hayato , Naik Sajo P , Okubo Tatsuya 
Published: May 2004

Abstract
A different comprehension from the conventional packing rule is discussed on the formation of films of Pm3n: a 3-D cubic mesoporous silica phase, SBA-1, followed by the mesophase of p6mm: a 2-D hexagonal mesoporous silica, SBA-3, where the phase is determined by the degree of silicate condensation.
Efficient Photocatalytic Oxidation of Cycloalkenes by Dihydroxo(tetraphenylporphyrinato)antimony Supported on Silica Gel under Visible Light Irradiation
Authors: Shiragami Tsutomu , Makise Ryu-ichi , Inokuchi Yousuke , Matsumoto Jin , Inoue Haruo , Yasuda Masahide 
Published: May 2004

Abstract
In order to develop a photocatalyst operating under visible light irradiation, silica gel-supported dihydroxo(tetraphenylporphyrinato)antimony (V) complex, [SbTPP(OH)2]+/SiO2, was prepared. The photocatalytic oxidation of cycloalkenes with oxygen molecule was performed on [SbTPP(OH)2]+/SiO2 particles under irradiation of fluorescent light. The photocatalytic oxidation of cycloalkenes gave the corresponding cis-1,2-epoxycycloalkane, 2-cycloalkene-1-ol, and trans-1,2-cycloalkanediol.
Preparation of Porous SnO2 Particles Having High Specific Surface Area and High Thermal Stability via an Aqueous Solution Route and Subsequent Hydrothermal Treatment
Authors: Ohgi Hirotoshi , Maeda Takahiro , Fujihara Shinobu , Imai Hiroaki 
Published: May 2004

Abstract
Hierarchically tailored SnO2 particles with a diameter of 200–500 nm were spontaneously formed in aqueous solutions dissolving SnF2 at 60 °C. The porous architecture of the particles was composed of SnO2 crystallites of ca. 5 nm in diameter and exhibited a high specific surface area of 130–230 m2/g. Subsequent hydrothermal treatment at 150°C improved the thermal stability of the SnO2 fine structure.
Bioinspired Modification of Polystyryl Matrix: Single-step Chemical Evolution to a Moderately Conducting Polymer
Authors: Saxena Ashutosh , Srivatsan S G , Saxena Vishal , Verma Sandeep 
Published: May 2004

Abstract
This report describes a simple, bioinspired approach for the conversion of an insulator, polystyrene, to a moderately conducting polymer by introducing adenine nucleobases.
Synthesis of N,N′-Disubstituted Urea from Ethylene Carbonate and Amine Using CaO
Authors: Fujita Shin-ichiro , Bhanage Bhalchandra M , Arai Masahiko 
Published: May 2004

Abstract
Calcium oxide has been proved to be an excellent solid catalyst for the synthesis of N,N′-disubstituted ureas from ethylene carbonate and primary amines under mild conditions.
Growth of Trigonal-shaped TiN Nanocrystals via the Metal-catalyzed Reduction-Nitridation Route at Low Temperature
Authors: Ma Xuchu , Zhang Zude , Li Xuebing , Wang Shutao , Du Yi , Xu Fen , Qian Yitai 
Published: May 2004

Abstract
Pure trigonal-shaped TiN nanocrystals with the size of 30–50 nm were synthesized from a metal-catalyzed reduction-nitridation (MCRN) route at 350 °C for 6 h, which used TiCl4 and NaNH2 as the starting materials and Mg metal as the catalyst. The obtained sample was characterized by XRD, TEM, and XPS. The effect of the metallic catalyst on the formation of the trigonal-shaped TiN nanocrystalline was discussed.
Novel Synthesis Method for Preparing Layered Li[Mn1/2Ni1/2]O2 as a Cathode Material for Lithium Ion Secondary Battery
Authors: Park Sang-Mok , Cho Tae-Hyung , Yoshio Masaki 
Published: May 2004

Abstract
We introduced a novel synthesis method, carbonate coprecipitation, for preparing Li[Mn1/2Ni1/2]O2 cathode. XRD experiment and ICP spectroscopy revealed that the cathode was successfully synthesized by the method. The cathode delivered discharge capacities of 151, 171.6, and 186.2 mAh/g at cut-off voltages 4.4, 4.5, and 4.6 V (vs Li/Li+), respectively. And the cathode retained 99.56% discharge capacity of the initial one at the 30th cycle with cut-off voltage 4.4 V (vs Li/Li+).
Arg410 near the Heme Proximal Ligand of Neuronal Nitric Oxide Synthase Is Critical for Both Substrate Recognition and Electron Transfer
Authors: Yadav Jyoti , Fujiwara Shigeyoshi , Sagami Ikuko , Shimizu Toru 
Published: May 2004

Abstract
Mutations at a well-conserved Arg410 located near the heme proximal axial ligand in the oxygenase domain of neuronal NOS (nNOS) abolished both substrate recognition and electron transfer to the heme, suggesting that this residue plays an important role in the architecture of the substrate recognition site and the electron transfer process.
Magnetic resonance imaging screening for vestibular schwannoma: analysis of published protocols
Authors: Obholzer R. J. , Rea P. A. , Harcourt J. P. 
Published: May 2004

This study seeks to define the most appropriate guidelines for selection of patients for magnetic resonance imaging (MRI) to exclude a vestibular schwannoma. Improved selection may reduce patient anxiety and improve resource utilization.All MRIs of the internal auditory meatus, performed during the year 2000, were reviewed. Audiograms and symptoms were collated for all ’positive’ scans and 100 negative scans. Information was analysed using seven published protocols and other defined frequency specific criteria.A diagnosis of vestibular schwannoma was made on 36 scans. Four criteria had a sensitivity of >95 per cent; of these the highest specificity (49 per cent) utilized an interaural difference at two adjacent frequencies of 15.dB in unilateral hearing loss and 20.dB in bilateral asymmetric loss.Applying our best protocol would have reduced the number of scans performed from 392 to 168. The one patient with a vestibular schwannoma who was excluded had trigeminal paraesthesia, an independent indication for investigation.
Modified Bondy radical mastoidectomy: long-term personal experience
Authors: Berrettini Stefano , Ravecca Francesca , De Vito Andrea , Forli Francesca , Valori Simone , Franceschini Stefano Sellari 
Published: May 2004

The ’Bondy operation’, or modified Bondy radical mastoidectomy, consists of a modification of the radical procedure by which the mastoid and epitympanum are exteriorized with preservation of the pars tensa and ossicular chain.In the 10-year period from 1986 to 1996, 53 patients of the ENT Department of the University of Pisa underwent a modified Bondy radical mastoidectomy, performed with a personalized procedure; 45 of them had a follow up of at least five years. After the surgical operation, the ears were free of complications in 38 cases (84.5 per cent), while in the other seven cases residual cholesteatoma (one case), tympanic retraction (four cases) or recurrent otorrhoea and phlogosis (two cases) were observed. The post-operative hearing level was unchanged or improved in 41 patients (91 per cent) (33 subjects had an unchanged gap and eight an improved gap), and only in the remaining four cases was the gap made worse. Based on our experience, the modified Bondy radical mastoidectomy is an extremely effective operation with a clear place in modern ENT surgery. When performed on carefully selected patients, it has been proven to offer good functional and anatomical results.
Efficacy of endoscopic sinus surgery for paranasal sinus mucocele including modified endoscopic Lothrop procedure for frontal sinus mucocele
Authors: Khong Jwu Jin , Malhotra Raman , Selva Dinesh , Wormald Peter John 
Published: May 2004

This study evaluated the efficacy of the modified endoscopic Lothrop procedure (MELP) for complicated frontal mucoceles and endoscopic marsupialization for other paranasal sinus mucoceles. It was a retrospective, consecutive case review of sinus mucoceles treated endoscopically by a single surgeon over a four-year period (1998-2002). There were 41 mucoceles in 28 patients, including 24 frontal, eight frontoethmoidal, three ethmoidal, five maxillary and one frontal mucocele. Twenty-one patients underwent the modified Lothrop procedure for frontal mucoceles, and seven underwent simple drainage and marsupialization for frontoethmoidal, ethmoidal and maxillary mucoceles. At median follow-up of 16 months, all patients had a patent mucocele opening. Patients treated by drainage and marsupialization did not have any complications or mucocele recurrence. All patients treated by the modified endoscopic Lothrop procedure had improvement in symptoms and signs. Four patients had minor complications including
epistaxis and adhesions and five required further surgery. The average hospital in-patient stay was 2 ± 1.4 days. Endoscopic techniques, including MELP are effective in the short term for the management of complex and simple paranasal sinus mucoceles. MELP has a useful place in the management of mucoceles with a significant bony partition from an adjacent sinus or nasal cavity. It is also indicated
when the mucocele is associated with loss of lateral support in the sinus with risk of medial-wall collapse of the orbital contents obstructing drainage.
Cavernous angioma of the internal auditory canal
Authors: Aquilina Kristian , Nanra Jagdeep S. , Brett Francesca , Walsh Rory McConn , Rawluk Daniel 
Published: May 2004

Cavernous angiomas of the internal auditory canal are rare lesions. The authors present a case of a 29-year-old lady with multiple infratentorial cavernous angiomas, whose sister had previously undergone surgery for a similar supratentorial lesion. She initially presented with an acute brainstem haematoma, secondary to a pontine cavernous angioma. Three years later she developed progressive right-sided sensorineural hearing loss and facial nerve paresis due to an internal auditory canal lesion. This was removed via the translabyrinthine approach and was found to be a cavernous angioma. This report underlines the multiple and dynamic nature of familial cavernous angiomas, as well as the importance of follow up to determine whether new symptoms are due to the enlargement of known angiomas or the development of new ones. As far as the authors are aware, this is the first report describing a cavernous angioma of the internal auditory canal in the context of familial and multiple infratentorial angiomas.
Mid-line swelling of the palate
Authors: Suresh Lakshmanan , Calixto Luis Edmundo Martinez , Aguirre Alfredo , Fischman Stuart L. 
Published: May 2004

Sarcoidosis is a multi-system, non-caseating granulomatous disease of unknown aetiology that may affect any organ. The oral involvement of sarcoidosis is rare and usually an initial manifestation of the disease. In this case report the authors present a 25-year-old African-American woman with palatal sarcoidosis treated successfully with intra-lesional corticosteroid injections. The oral manifestationsof sarcoidosis are relatively uncommon and may be the only manifestation of the disease. Suspected cases of oral sarcoidosis should be biopsied and subsequently referred to a physician to rule out systemic involvement.
Do Promotions Benefit Manufacturers, Retailers, or Both?
Authors: Srinivasan Shuba , Pauwels Koen , Hanssens Dominique M. , Dekimpe Marnik G. 
Published: May 2004

Do price promotions generate additional revenue and for whom? Which brand, category, and market conditions influence promotional benefits and their allocation across manufacturers and retailers? To answer these questions, we conduct a large-scale econometric investigation of the effects of price promotions on manufacturer revenues, retailer revenues, and total profits (margins). A first major finding is that a price promotion typically does not have permanent monetary effects for either party. Second, price promotions have a predominantly positive impact on manufacturer revenues, but their effects on retailer revenues are mixed. Moreover, retailer category margins are typically reduced by price promotions. Even when accounting for cross-category and store-traffic effects, we still find evidence that price promotions are typically not beneficial to the retailer. Third, our results indicate that manufacturer revenue elasticities are higher for promotions of small-share brands, for frequently promoted brands and for national brands in impulse product categories with a low degree of brand proliferation and low private-label shares. Retailer revenue elasticities are higher for brands with frequent and shallow promotions, for impulse products, and in categories with a low degree of brand proliferation. Finally, retailer margin elasticities are higher for promotions of small-share brands and for brands with infrequent and shallow promotions. We discuss the managerial implications of our results for both manufacturers and retailers.