bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Species of the Isolated Psaroniaceous Rachis from the Early Permian in China
Authors: Xiang Ning , Ma Shi‐Min , Tian Bao‐Lin , Wang Shi‐Jun , Zhang Ming‐Shan 
Published: November 2008

Abstract A new kind of marattialean raches are reported from the coal balls in Coal Seam No.7 in the upper part of the Taiyuan Formation (early Early Permian) from Taiyuan, Shanxi, China and are assigned to the genus Stipitopteris Grand'Eury (Psaroniaceae). The present specimens are different from all six reported species of the genus, and are therefore proposed as a new species: Stipitopteris shanxiensis. The raches of the new species are generally dorsi‐ventrally flattened. The main raches usually exhibit scales of different forms on their surface. Beneath the epidermis is a zone of parenchymatous cells, some of which contain tannin‐like contents. Inside this is a zone of small sclerenchymatous cells. Inward are the ground tissue and vascular bundles. The vascular bundles are continuous and are in two circles: the outer circle assumes a transversely elliptical shape with the gap and pinna trace, and the inner circle assumes a shallow C‐shape with inrolled ends. The ground tissue located at the inner side of the vascular bundle is composed of thicker‐walled parenchymatous cells. The cells of the ground tissue are vertically elongated in longitudinal sections. Subordered raches are smaller and have simpler structures than the main raches. The parenchyma zone beneath the epidermis is thinner, usually one to two cells wide and the sclerenchyma zone is usually absent. The scales are poorly developed and there is only one C‐shaped vascular bundle. The new species is comparable to the crosiers of Psaroniaceae of the Euramerican Flora in some aspects, for example, it has a dorsi‐ventrally flattened rachis and scales on the surface of the rachis. However, the other features and the preservative conditions of the present specimens indicate that they are not crosiers, but fully developed or mature raches. The new species is the first well‐studied anatomically‐preserved rachis of Psaroniaceae from the Cathaysian Flora and bears significance not only in understanding the anatomy and taxonomy of Psaroniaceae in the Cathaysian Flora, but also in the relationship between the Euramerican Flora and the Cathaysian Flora.
Hydrogen Peroxide in Plants: a Versatile Molecule of the Reactive Oxygen Species Network
Authors: Quan Li‐Juan , Zhang Bo , Shi Wei‐Wei , Li Hong‐Yu 
Published: November 2008

Abstract Plants often face the challenge of severe environmental conditions, which include various biotic and abiotic stresses that exert adverse effects on plant growth and development. During evolution, plants have evolved complex regulatory mechanisms to adapt to various environmental stressors. One of the consequences of stress is an increase in the cellular concentration of reactive oxygen species (ROS), which are subsequently converted to hydrogen peroxide (H2O2). Even under normal conditions, higher plants produce ROS during metabolic processes. Excess concentrations of ROS result in oxidative damage to or the apoptotic death of cells. Development of an antioxidant defense system in plants protects them against oxidative stress damage. These ROS and, more particularly, H2O2, play versatile roles in normal plant physiological processes and in resistance to stresses. Recently, H2O2 has been regarded as a signaling molecule and regulator of the expression of some genes in cells. This review describes various aspects of H2O2 function, generation and scavenging, gene regulation and cross‐links with other physiological molecules during plant growth, development and resistance responses.
Selenium‐induced Changes in Activities of Antioxidant Enzymes and Content of Photosynthetic Pigments in Spirulina platensis
Authors: Chen Tian‐Feng , Zheng Wen‐Jie , Wong Yum‐Shing , Yang Fang 
Published: November 2008

Abstract
Spirulina platensis exposed to various selenium (Se) concentrations (0, 10, 20, 40, 80, 150, 175, 200, 250 mg/L) accumulated high amounts of Se in a dose‐ and time‐dependent manner. Under low Se concentrations (≤150 mg/L), Se induced increases in biomass concentration, content of photosynthetic pigments, and activities of glutathione peroxidase (GPX), superoxide dismutase (SOD), catalase (CAT) and Gua‐dep peroxidases (POD), which indicates that antioxidant enzymes play an important role in protecting cells from Se stress. Higher Se concentrations (≥ 175 mg/L) led to higher Se accumulation and increases in activities of GPX, SOD, CAT and POD, but also induced lipid peroxidation (LPO) coupled with potassium leakage and decreases in biomass concentration and contents of photosynthetic pigment. The results indicate that increases in activities of the antioxidant enzymes were not sufficient to protect cell membranes against Se stress. Time‐dependent variations in the activities of antioxidant enzymes, contents of chlorophyll a and carotenoid and the LPO level were also investigated under representative Se concentrations of 40 and 200 mg/L. Opposite variation trends between SOD‐CAT activities, and GPX‐POD‐APX activities were observed during the growth cycles. The results showed that the prevention of damage to cell membranes of S. platensis cells could be achieved by cooperative effects of SOD‐CAT and GPX‐POD‐APX enzymes. This study concludes that S. platensis possessed tolerance to Se and could protect itself from phytotoxicity induced by Se by altering various metabolic processes.
In vitro comparison of different reciprocating systems used during endodontic retreatment
Authors: Zanettini Paulo Roberto , Barletta Fernando Branco , De Mello Rahde Nicole 
Published: November 2008

AbstractThe present study evaluated the effectiveness of two reciprocating systems for the removal of root‐filling material during endodontic retreatment. One hundred extracted mandibular premolars were prepared and root‐filled with gutta‐percha and sealer. Root fillings were removed with K‐files according to the following techniques: Group A – hand instrumentation; Group B – Endo‐Gripper system driven by compressed air; Group C – INTRAmatic 29CH + INTRA‐LUX 3LD driven by compressed air; Group D – Endo‐Gripper system driven by electric engine; Group E – INTRAmatic 29CH + INTRA‐LUX 3LD driven by electric engine. The amount of filling debris on root canal walls was assessed radiographically and analysed using Auto CAD 2000 software. One‐way anova and Duncan’s test revealed statistically significant differences only in the middle third (P = 0.01); the best results being reached in group D. The apical third displayed the greatest amount of filling material debris, regardless of the technique used.
Mandibular molar with five root canals
Authors: Barletta Fernando Branco , Dotto Sidney Ricardo , Reis Magda de Sousa , Ferreira Ronise , Travassos Rosana Maria Coelho 
Published: November 2008

AbstractThe purpose of this study was to demonstrate the importance of knowledge of the internal anatomy of root canals for the success of endodontic treatment. Lack of knowledge of anatomic variations and their characteristics in different teeth has been pointed out as one of the main causes of endodontic therapy failure. In this report, the authors describe the endodontic treatment of a mandibular first molar with five root canals, evaluate the rate of occurrence of this number of canals, and discuss the importance of their identification and treatment.
Second mesiobuccal canal detection in maxillary first molars using microscopy and ultrasonics
Authors: Alaçam Tayfun , Tinaz Ali Cemal , Genç Özgür , Kayaoglu Guven 
Published: November 2008

AbstractThe aim of this study was to investigate whether the use of operating microscope in combination with ultrasonics increased the rate of second mesiobuccal (MB2) canal detection in permanent maxillary first molar teeth. A hundred extracted human maxillary first molars were assessed. After location of the main canals, the MB2 canal was sought in all teeth first without microscopy, then with the aid of the operating microscope and finally with the combined use of the operating microscope and ultrasonics. With these techniques, the MB2 canal was detected in 62%, 67% and 74% of the teeth, respectively. The combination of the operating microscope and ultrasonics detected significantly more MB2 canals than when no microscopy was utilized (P < 0.05). Sectioning of the roots disclosed the presence of the MB2 canal in 82% of the teeth. Twenty‐nine per cent of the teeth had a separate MB2 canal orifice and separate apical foramina. The results of this study suggested that the combined use of the operating microscope and ultrasonics increased the detection of MB2 canals in maxillary first permanent molars.
Effectiveness of a 2% chlorhexidine solution mixed with calcium hydroxide against Candida albicans
Authors: Al‐Nazhan Saad , Al‐Obaida Mohammed 
Published: November 2008

AbstractThe purpose of this investigation was to examine the in vitro susceptibility of Candida albicans to a mixture of chlorhexidine and calcium hydroxide using a tube dilution test. A suspension containing C. albicans was exposed to 2% chlorhexidine solution, calcium hydroxide paste and 2% chlorhexidine mixed with calcium hydroxide in plastic tissue culture wells. The tested agents were incubated with C. albicans for 1, 24, or 72 h. All agents were effective anti‐fungals at all experimental time periods tested, with the exception of exposure to calcium hydroxide for 1 h. A mixture of 2% chlorhexidine and calcium hydroxide therefore is a very effective anti‐fungal agent against C. albicans.
An Inferentialist Approach to Semantics: Time for a New Kind of Structuralism?
Authors: Peregrin Jaroslav 
Published: November 2008

AbstractThe perennial question –What is meaning?– receives many answers. In this paper I present and discuss inferentialism– a recent approach to semantics based on the thesis that to have (such and such) a meaning is to be governed by (such and such) a cluster of inferential rules. I point out that this thesis presupposes that looking for meaning requires seeing language as a social institution (rather than, say, a psychological reality). I also indicate that this approach may be seen as a new embodiment of the old ideas of structuralism.
Preempting Principles: Recent Debates in Moral Particularism
Authors: McKeever Sean , Ridge Michael 
Published: November 2008

AbstractMoral particularism, as recently defended, charges that traditional moral theorizing unduly privileges moral principles. Moral generalism defends a prominent place for moral principles. Because moral principles are often asked to play multiple roles, moral particularism aims at multiple targets. We distinguish two leading roles for moral principles, the role of standard and the role of guide. We critically survey some of the leading arguments both for and against principles so conceived.
Can Physicalism Be Non‐Reductive?
Authors: Melnyk Andrew 
Published: November 2008

AbstractCan physicalism (or materialism) be non‐reductive? I provide an opinionated survey of the debate on this question. I suggest that attempts to formulate non‐reductive physicalism by appeal to claims of event identity, supervenience, or realization have produced doctrines that fail either to be physicalist or to be non‐reductive. Then I treat in more detail a recent attempt to formulate non‐reductive physicalism by Derk Pereboom, but argue that it fares no better.
Persistence and Location in Relativistic Spacetime
Authors: Gilmore Cody 
Published: November 2008

AbstractHow is the debate between endurantism and perdurantism affected by the transition from pre‐relativistic spacetimes to relativistic ones? After suggesting that the endurance vs. perdurance distinction may run together a pair of cross‐cutting distinctions (mereological endurance vs. mereological perdurance and locational endurance vs. locational perdurance), I discuss two recent attempts to show that the transition in question does serious damage to endurantism (at least of the locational variety).
Regulation of alveolar gas conductance by NO in man, as based on studies with NO donors and inhibitors of NO production
Authors: Guazzi M. , Arena R. , Vicenzi M. , Guazzi M. D. 
Published: November 2008

AbstractAim:  Nitric oxide (NO) is a mediator of the pulmonary vessel tone and permeability. We hypothesized that it may also regulate the alveolar‐capillary membrane gas conductance and lung diffusion capacity.Methods:  In 20 healthy subjects (age = 23 ± 3 years) we measured lung diffusion capacity for carbon monoxide (DLco), its determinants (membrane conductance, Dm, and pulmonary capillary blood volume, Vc), systolic pulmonary artery pressure (PAPs) and pulmonary vascular resistance (PVR). Measurements were performed before and after administration of Ng‐monomethyl‐l‐arginine (l‐NMMA, 0.5 mg kg−1 min−1), as a NO production inhibitor, and l‐arginine (l‐Arg, 0.5 mg kg−1 min1) as a NO pathway activator. The effects of l‐NMMA were also tested in combination with active l‐Arg and inactive stereoisomer d‐Arg vehicled by 150 mL of 5%d‐glucose solution. For l‐Arg and l‐NMMA, saline (150 mL) was also tested as a vehicle.Results:  l‐NMMA reduced Dm (−41%P < 0.01), DLco (−20%, P < 0.01) and cardiac output (CO), and increased PAPs and PVR. In 10 additional subjects, a dose of l‐NMMA of 0.03 mg kg−1 min1 infused in the main stem of the pulmonary artery was able to lower Dm (−32%, P < 0.01) despite no effect on PVR and CO. Dm depression was significantly greater when l‐NMMA was vehicled by saline than by glucose. l‐Arg but not d‐Arg abolished the effects of l‐NMMA. l‐Arg alone increased Dm (+14%, P < 0.01).Conclusion:  The findings indicate that NO mediates the respiratory effects of l‐NMMA and l‐Arg, and is involved in the physiology of the alveolar‐capillary membrane gas conductance in humans. NO deficiency may cause an excessive endothelial sodium exchange/water conduction and fluid leakage in alveolar interstitial space, lengthening the air–blood path and depressing diffusion capacity.
Vastus lateralis surface and single motor unit electromyography during shortening, lengthening and isometric contractions corrected for mode‐dependent differences in force‐generating capacity
Authors: Altenburg T. M. , De Ruiter C. J. , Verdijk P. W. L. , Van Mechelen W. , De Haan A. 
Published: November 2008

AbstractAim:  Knee extensor neuromuscular activity, rectified surface electromyography (rsEMG) and single motor unit EMG was investigated during isometric (60° knee angle), shortening and lengthening contractions (50–70°, 10° s−1) corrected for force–velocity‐related differences in force‐generating capacity. However, during dynamic contractions additional factors such as shortening‐induced force losses and lengthening‐induced force gains may also affect force capacity and thereby neuromuscular activity. Therefore, even after correction for force–velocity‐related differences in force capacity we expected neuromuscular activity to be higher and lower during shortening and lengthening, respectively, compared to isometric contractions.Methods:  rsEMG of the three superficial muscle heads was obtained in a first session [10 and 50% maximal voluntary contraction (MVC)] and additionally EMG of (46) vastus lateralis motor units was recorded during a second session (4–76% MVC). Using superimposed electrical stimulation, force‐generating capacity for shortening and lengthening contractions was found to be 0.96 and 1.16 times isometric (Iso) force capacity respectively. Therefore, neuromuscular activity during submaximal shortening and lengthening was compared with isometric contractions of respectively 1.04Iso (=1/0.96) and 0.86Iso (=1/1.16). rsEMG and discharge rates were normalized to isometric values.Results:  rsEMG behaviour was similar (P > 0.05) during both sessions. Shortening rsEMG (1.30 ± 0.11) and discharge rate (1.22 ± 0.13) were higher (P < 0.05) than 1.04Iso values (1.05 ± 0.05 and 1.03 ± 0.04 respectively), but lengthening rsEMG (1.05 ± 0.12) and discharge rate (0.90 ± 0.08) were not lower (P > 0.05) than 0.86Iso values (0.76 ± 0.04 and 0.91 ± 0.07 respectively).Conclusion:  When force–velocity‐related differences in force capacity were taken into account, neuromuscular activity was not lower during lengthening but was still higher during shortening compared with isometric contractions.
Perspectives of multi‐modal contribution of honeybee resources to our life
Authors: HOSHIBA Hidehiro , SASAKI Masami 
Published: November 2008

AbstractThe European honeybee, Apis mellifera, has been introduced to all continents and their products like honey, propolis, royal jelly and beeswax are well known. However, its contribution is not restricted to such direct products but extends into a much wider area. For example, the economic value of seed production by pollination exceeds the above‐mentioned bee products. The application of F1 hybrid is increased to as much as 70% of commercial crops and flowers in Japan and honeybees are important pollinators in the F1 seed production. Incorporation into the large‐scale biodiesel fuel production system by culturing rape and sunflower seeds etc. is relied on because it is good to construct possible zero‐emission systems that reduce carbon dioxide and increase the rich by‐products like honey and royal jelly.Bees’ higher brain function and sophisticated social system of the colony opens new perspectives as a model system. Their individual ability to recognize even abstract concepts is comparable to that of higher primates. Rats or mice have no such ability. High performance learning ability of bees associated with proboscis extension reflex can be used to detect drugs at the airport. Function of the colony, on the other hand, is an excellent model for social physiology or a self‐organization system.After the whole genome of A. mellifera was read in 2006 by the world consortium, consisting of more than 90 institutions from all over the world, many molecular biologists are coming into bee world. Nobody has yet succeeded in the challenge to make transgenic honeybee, so far, because of the difficulty in controlling the reproductive system headed by the queen. However, if someone succeeded in a breakthrough we will have stingless honeybees and a disease‐resistant strain in the future.
Mass rearing an earth mite to screen plants for resistance: A review
Authors: RIDSDILL‐SMITH T. James 
Published: November 2008

AbstractA mite which is polyphagous, widespread and abundant should be relatively easy to rear. However, mass rearing redlegged earth mite, Halotydeus destructor, for use in screening plants for resistance, has been very difficult. They are found in regions of Australia with winter growing annual crops and pastures, where they are active in winter and have a summer diapause. Mites are field collected in winter for screening, but cold storage only improves availability by 2 weeks. If mites are held in controlled climate cabinets under winter conditions with short daylength, the onset of diapause is not triggered and egg laying continues. Host plant suitability is a key factor affecting the rate of multiplication of mites, and common vetch, Vicia sativa cv Blanchefleur is an optimum host for rearing. The mites spend 90% of the time on the soil surface and only climb to the upper plant canopy in pastures to feed for 10% of the time. They are thus earth mites. High humidity at the soil surface is very important for their survival and optimal multiplication. If it is too wet dead mites on the surface are attacked by verticillium fungus, and active mites are adversely affected by hyphae. Mite multiplication is greater on well‐drained sandy loam soil than a loamy soil, sand or pure loam as a substrate. Mass rearing has now been achieved after overcoming these problems.
Insects and their uses in a cold country: Finland
Authors: MEYER‐ROCHOW Victor Benno 
Published: November 2008

AbstractNorthern European countries, despite their geographic location and climatic conditions, have a considerable number of insect species. To date 20 532 species of insects are known from Finland. Honeybees were introduced to Finland in the 18th century. The total number of hives in the country today is 50 000, with each producing an annual 30–40 kg of honey. A considerable amount of research is carried out on bees in Finland by beekeepers and scientists and the Finnish Beekeeper Association publishes its own journal by the name of Mehiläinen for approximately 3300 subscribers. Insects also play important roles in the education and school curricula of Finnish children with insect boxes containing preserved specimens, identification keys and information on general biology available for classes. Some butterflies get framed and hung on walls, serving as room decorations. Insects also feature as motifs on Finnish t‐shirts. Forensic entomology was pioneered in Finland and numerous university departments (zoology, entomology, ecology, physiology, biophysics, pharmacology and genetics) as well as museums are engaged in research on insects. Monitoring climate change, insects in Finland (especially Lepidoptera) are highly suitable because of the many years of recorded distributions and abundances of species. Finally, the large amount of idioms in the Finnish language, making reference to insects, testifies to the intimate connection between the Finnish people and the insects of their country.
Identification and phylogeny of five male‐specific lethal genes in the silkworm Bombyx mori
Authors: LIU Wenbin , ZHANG Yong , MIAO Xuexia , HUANG Yongping 
Published: November 2008

AbstractIn the fruit fly (Drosophila melanogaster) dosage compensation equalization of X‐linked genes between the sexes is achieved via a complex that is termed the compensasome, which is composed of at least five male‐specific lethal (msl) genes and two non‐coding RNAs. In the present study, we cloned all five homologs (termed the msls) from the silkworm, Bombyx mori, in which the issue of dosage compensation remains controversial. Data mining and robust phylogenetic analysis revealed that msls are ubiquitously present in genomes, from insects to mammals, with unknown biological functions. However, the five genes seem to have evolved at different times due to gene duplication. Real‐time reverse transcriptase‐polymerase chain reaction experiments demonstrated that in the silkworm, some Z‐linked genes are expressed at higher levels in females than in males while others are expressed at lower levels in females than in males, which suggests that the msl genes in the silkworm and fruit fly may have different roles. We discussed the relationship of phylogeny between msl and sex‐lethal.