bluuebunny/crossref_metadata_2025 huggingface dataset:
Nucleocytoplasmic Transport of MicroRNAs and Related Small RNAs
Authors: Katahira Jun , Yoneda Yoshihiro
Published: April 2011

Small RNAs with lengths of 20–30 nucleotides, such as microRNAs (miRNAs), play important regulatory roles in various cellular processes. In conventional linear processing pathways, precursors of miRNAs are transported out of the nucleus by the specific nuclear transport receptor, exportin‐5. The exported precursors are further processed and eventually incorporated into the RNA‐induced silencing complex (RISC), which silences the expression of the target genes by posttranscriptional mechanisms in the cytoplasm. Subsequent identification and characterization of P‐element induced wimpy testis (PIWI)‐interacting small RNAs (piRNAs) and endogenous small interfering RNAs (endo‐siRNAs) revealed that the processing mechanisms of these newly emerging small RNAs differ from those of miRNAs. Moreover, cumulative experimental evidence indicates that the nuclear functions of the small RNAs, such as transcriptional gene silencing, could be widespread in divergent species. These observations appended other interesting features in the biogenesis and nucleocytoplasmic transport mechanisms of these small RNAs. In this review, we discuss the mechanisms and biological significance of the intracellular trafficking of small RNAs in animal cells.
Left‐to‐right distribution of periodontal disease
Authors: Darby IB , Polster A , Gan JS , Guo Q , Henein N , Heredia A , Horina H , Sanduja D , Radvar M
Published: April 2011

To cite this article:
 
Int J Dent Hygiene
10, 2012; 74–79  DOI: 10.1111/j.1601‐5037.2011.00509.x  Darby IB, Polster A, Gan JS, Guo Q, Henein N, Heredia A, Horina H, Sanduja D, Radvar M. Left‐to‐right distribution of periodontal disease.

Abstract:  Aim:  Symmetry is a property established in many human biological systems and it is reasonable to expect that it may also exist in the mouth. The objective of this study was to examine whether there is a similar left‐to‐right distribution in periodontal disease.

Method:  Records of 197 patients from the Periodontics department of The Royal Dental Hospital of Melbourne were analysed. The clinical parameters recorded were pocket probing depth, recession, bleeding on probing, mobility and furcation involvement.

Results:  The average age of our sample group was 47.5 years old, with 34.5% men and 65.5% women. The results demonstrated significant left‐to‐right distribution with all the periodontal indices recorded.

Conclusion:  The findings support previous studies that show that a similar left‐to‐right distribution exists in the population studied.
Identification of a Stable Quantitative Trait Locus for Percentage Grains with White Chalkiness in Rice (Oryza sativa)
Authors: Guo Tao , Liu Xiaolu , Wan Xiangyuan , Weng Jianfeng , Liu Shijia , Liu Xi , Chen Mingjiang , Li Jingjing , Su Ning , Wu Fuqing , Cheng Zhijun , Guo Xiuping , Lei Cailin , Wang Jiulin , Jiang Ling , Wan Jianmin
Published: April 2011

High chalkiness is a major problem in many rice‐producing areas of the world, especially in hybrid rice (Oryza sativa L.) in China. We previously showed a major quantitative trait locus for the percentage of grains with white chalkiness (QTLqPGWC‐8) in the interval G1149‐R727 on chromosome 8 using a chromosome segment substitution line (CSSL). Here, we selected the line‐CSSL50 harboring the QTLqPGWC‐8 allele from the CSSLs derived from a cross between Asominori (as a recurrent parent) and IR24 (as a donor parent), which had higher percentage chalkiness, markedly different from that of Asominori. There were also significant differences in starch granules, appearance of amylose content (AAC) and milling qualities between Asominori and CSSL50, but not in grain size or thousand grain weight (TGW). The BC4F2 and BC4F3 populations from a cross between CSSL50 and Asominori were used for fine mapping of qPGWC‐8. We narrowed down the location of this QTL to a 142 kb region between Indel markers 8G‐7 and 8G‐9. QTLqPGWC‐8 accounted for 50.9% of the difference in PGWC between the parents. The markers tightly linked to qPGWC‐8 should facilitate cloning of the gene underlying this QTL and will be of value for marker‐assisted selection in breeding rice varieties with better grain quality.
Higher Order Analytical Solutions of Water Table Fluctuations in Coastal Aquifers
Authors: Stojsavljevic J.D. , Jeng D.‐S. , Seymour B.R. , Pokrajac D.
Published: April 2011

The groundwater response of coastal aquifers to tidal forcing is described by Laplace's equation coupled with the nonlinear phreatic‐free surface boundary condition. Here we describe fluctuations in the water table using two small parameters, extending previous work by proposing an ansatz to compute higher order, semi‐analytical solutions. The new solutions are compared with known lower order solutions. The relative difference between the linear solution and higher order solutions can reach up to 30% of the linear solution for shallow beaches. The new solutions exhibit a reduction in the over height of the groundwater fluctuations compared with the lower order solutions. In addition, the super elevation of the water table, both near shore and as the aquifer tends landward, is examined with the inclusion of higher order terms.
An Analysis of River Bank Slope and Unsaturated Flow Effects on Bank Storage
Authors: Doble Rebecca , Brunner Philip , McCallum James , Cook Peter G.
Published: April 2011

Recognizing the underlying mechanisms of bank storage and return flow is important for understanding streamflow hydrographs. Analytical models have been widely used to estimate the impacts of bank storage, but are often based on assumptions of conditions that are rarely found in the field, such as vertical river banks and saturated flow. Numerical simulations of bank storage and return flow in river‐aquifer cross sections with vertical and sloping banks were undertaken using a fully‐coupled, surface‐subsurface flow model. Sloping river banks were found to increase the bank infiltration rates by 98% and storage volume by 40% for a bank slope of 3.4° from horizontal, and for a slope of 8.5°, delay bank return flow by more than four times compared with vertical river banks and saturated flow. The results suggested that conventional analytical approximations cannot adequately be used to quantify bank storage when bank slope is less than 60° from horizontal. Additionally, in the unconfined aquifers modeled, the analytical solutions did not accurately model bank storage and return flow even in rivers with vertical banks due to a violation of the dupuit assumption. Bank storage and return flow were also modeled for more realistic cross sections and river hydrograph from the Fitzroy River, Western Australia, to indicate the importance of accurately modeling sloping river banks at a field scale. Following a single wet season flood event of 12 m, results showed that it may take over 3.5 years for 50% of the bank storage volume to return to the river.
5′‐Phosphonate Derivatives of 2′,3′‐Dideoxy‐3′‐Thiacytidine as New Anti‐HIV Prodrugs
Authors: Khandazhinskaya Anastasia L. , Jasko Maxim V. , Karpenko Inna L. , Solyev Pavel N. , Golubeva Natalia A. , Kukhanova Marina K.
Published: April 2011

Two new phosphonate 3TC prodrugs were synthesized and studied in MT‐4 cells as inhibitors of HIV replication. Their pharmacokinetic parameters were evaluated following intragastric administration in rabbits and oral administration in dogs. Both compounds were much less toxic than parent 3TC in cell cultures and could generate the active nucleoside in laboratory animals.
The closing and opening of TRPC channels by Homer1 and STIM1
Authors: Yuan J. P. , Lee K. P. , Hong J. H. , Muallem S.
Published: April 2011

Influx of Ca2+ is a central component of the receptor‐evoked Ca2+ signal. A ubiquitous form of Ca2+ influx comes from Ca2+ channels that are activated in response to depletion of the endoplasmic reticulum Ca2+ stores and are thus named the store‐operated Ca2+‐influx channels (SOCs). One form of SOC is the transient receptor potential canonical (TRPC) channels. A major question in the field of Ca2+ signalling is the molecular mechanism that regulates the opening and closing of these channels. All TRPC channels have a Homer‐binding ligand and two conserved negative charges that interact with two terminal lysines of the stromal interacting molecule 1 (STIM1). The Homer and STIM1 sites are separated by only four amino acid residues. Based on available results, we propose a molecular mechanism by which Homer couples TRPC channels to IP3 receptors (IP3Rs) to keep these channels in the closed state. Dissociation of the TRPCs‐Homer‐IP3Rs complex allows STIM1 access to the TRPC channels negative charges to gate open these channels.
Vasomotion – what is currently thought?
Authors: Aalkjær C. , Boedtkjer D. , Matchkov V.
Published: April 2011

This minireview discusses vasomotion, which is the oscillation in tone of blood vessels leading to flowmotion. We will briefly discuss the prevalence of vasomotion and its potential physiological and pathophysiological relevance. We will also discuss the models that have been suggested to explain how a coordinated oscillatory activity of the smooth muscle tone can occur and emphasize the role of the endothelium, the handling of intracellular Ca2+ and the role of smooth muscle cell ion conductances. It is concluded that vasomotion is likely to enhance tissue dialysis, although this concept still requires more experimental verification, and that an understanding at the molecular level for the pathways leading to vasomotion is beginning to emerge.
Improving occurrence‐based rarity metrics in conservation studies by including multiple rarity cut‐off points
Authors: LEROY BORIS , PETILLON JULIEN , GALLON REGIS , CANARD ALAIN , YSNEL FREDERIC
Published: April 2011

Abstract. 1. This study aims to develop a new method for assigning rarity weights to species in evaluations of the relative rarity of arthropod assemblages in conservation/monitoring studies.

2. A flexible characteristic was included in the rarity weighting method by introducing the possibility of fitting the method to a rarity cut‐off point defined as the threshold of occurrence below which species are considered as being rare. This allows calculation of a rarity metric (index of relative rarityIRR) with multiple rarity cut‐off points.

3. The proposed weighting method was used and compared with three previously proposed methods in a theoretical analysis.IRRvalues were then calculated for spider assemblages of a National Nature Reserve in France. Two methods of rankings were proposed: a local ranking between sites of the Nature Reserve, and aregional rankingin comparison to a reference database.

4. The proposed weighting method consistently weighted species according to the chosen rarity cut‐offs. Species weights were less biased toward common species and rare species weights were less dispersed than with previous methods. Assemblages were consistently ranked according to the rarity of spiders in each assemblage. The index showed different patterns of rarity in assemblages which could not be detected by previous rarity metrics.

5. This method provides an improved understanding of assemblage rarity patterns relative to previous methods and can be consistently applied to other arthropod taxa in other geographic area and/or spatial scales.
Detrital Zircon Dating of Meso‐ and Neoproterozoic Rocks in North China and Its Implications
Authors: GAO Linzhi , LIU Pengju , YIN Chongyu , ZHANG Chuanheng , DING Xiaozhong , LIU Yanxue , SONG Biao
Published: April 2011

New dates from Meso‐ and Neoproterozoic strata contribute to the recently defined Precambrian stratigraphical timescale of China agreed by the Subcommission on the Precambrian System, and the National Commission on Stratigraphy of China on Nov. 24, 2009. First, the age range of the Changcheng System, including the Changzhougou, Chuanlinggou, Tuanshanzi and Dahongyu formations has been constrained to 1.8–1.6 Ga. Second, the Jixian System including the Gaoyuzhuang, Yangzhuang, Wumishan, Hongshuizhuang and Tieling formations has been constrained to 1.6–1.4 Ga. Third, an as‐yet unnamed (undefined) system (1.4–1.0 Ga) is only developed in the Xiamaling Formation at the Jixian section, Tianjing. Fourth, the Qingbaikou System, including the Luotuoling and Jing'eryu formations has been constrained to 1.0–0.78 Ga. Fifth, the Nanhuan System ranges between 780–635 Ma, and the Sinian System is within 635–542 Ma. However, according to a series of SHRIMP U‐Pb dates from the late Precambrian in the Jiangnan Orogen Belt in South China Platform, the constrained strata will be redefined as in the upper part of the Qingbaikou System. To aid global geodynamics, it is useful to denote a late Precambrian section with unified, precise and high‐precision chronological dating; this is here defined in North China Block and Jiaoliao‐Korean Block. However, the Neoproterozoic Qingbaikou study in North China will be influence in whole Meso‐ and Neoproterozoic in the Jiangnan Orogenic Belt in between the Yangtze Block and the Cathaysia Block in South China.
Acanthomorph Biostratigraphic Succession of the Ediacaran Doushantuo Formation in the East Yangtze Gorges, South China
Authors: YIN Chongyu , LIU Pengju , AWRAMIK Stanley M. , CHEN Shouming , TANG Feng , GAO Linzhi , WANG Ziqiang , RIEDMAN Leigh A.
Published: April 2011

Large acanthomorphic acritarchs have been found in chert of the Ediacaran Doushantuo Formation at several localities in South China, including the East Yangtze Gorges of Hubei Province, Weng'an area of Guizhou Province, and elsewhere. However, their potential for biostratigraphic subdivision and correlation of Ediacaran successions is limited by facies control, taphonomic biases, and taxonomic problems. In the Yangtze Gorges, the Doushantuo Formation is generally subdivided into four lithologic members. However, in the Weng'an area, the Doushantuo Formation comprises just a lower and upper part separated by a mid‐Doushantuo erosional surface. In the Yangtze Gorges at the Zhangcunping section, the Doushantuo succession is similar to that at Weng'an. So far, the correlation between the Yangtze Gorges and Weng'an area, and elsewhere has been an issue of debate. To resolve the debate, we selected eight sections in the Yangtze Gorges area and systemically sampled chert nodules of the Doushantuo Formation, focusing in particular on the upper Doushantuo Formation. Our data confirm two different assemblages appearing separately in the second and third members, which are separated by a negative δ13C excursion (EN2). The lower assemblage is characterized by Tianzhushania and a diverse suite of large acanthomorphic acritarchs. The upper assemblage is distinguished from the lower assemblage, by (1) absence of Tianzhushania; (2) occurrence of abundant, 100–150 μm, smooth‐walled spherical microfossils; (3) occurrence of highly diverse acanthomorphic acritarchs including species extending from the second member and new forms in this member; (4) occurrence of unnamed new forms of protist; and (5) occurrence of the tubular microfossil Sinocyclocylicus guizhouensis. Since the Tianzhushania‐dominated assemblage is not present in Australia, it seems that only the upper acanthomorph assemblage is present and thus the lower Doushantuo acanthomorph assemblage is missing in Australia.
Biostratigraphic and Chemostratigraphic Correlation for the Base of the Middle Ordovician between Yichang and Western Zhejiang Areas, South China
Authors: ZHANG Yuandong , MUNNECKE Axel , CHEN Xu , CHENG Junfeng , LIU Xiao
Published: April 2011

The base of the Middle Ordovician (i.e. Dapingian Stage) has been defined at the first appearance datum (FAD) of conodont Baltoniodus?triangularis at Huanghuachang, Yichang, China, but the precise correlation of the boundary to regions of other facies remain to be resolved. Herein we review the biostratigraphy and chemostratigraphy of the Huanghuachang Global Standard Stratotype‐Section and Point (GSSP) section, and present our latest stratigraphic work on the nearby Chenjiahe section in Yichang, and the Hengtang Quarry section, Jiangshan, Zhejiang, which is regarded as representative of slope facies. The conodont and graptolite biostratigraphy as well as chemostratigraphy of the Chenjiahe section indicate that the base of the Middle Ordovician also falls within the graptolite Azygograptus suecicus Zone, and coincides with a high or maximum δ13C value within a minor positive carbon isotope excursion, suggesting that the base boundary can be readily recognized across the entire Yangtze Gorges area. The integrated graptolite and conodont biostratigraphy and chemostratigraphy of the Hengtang section, Jiangshan, indicates that the basal boundary probably falls within the graptolite Isograptus caduceus imitatus Zone that overlies the Azygograptus suecicus Zone, and coincides with a remarkable drop of δ13C. This difference indicates that a multi‐disciplinary approach is critical to identify the base boundary in those regions where the Baltoniodus?triangularis is absent
Geochemical Stratigraphy and Microvertebrate Assemblage Sequences across the Silurian/Devonian Transition in South China
Authors: ZHAO Wenjin , WANG Nianzhong , ZHU Min , MANN Ulrich , HERTEN Ulrich , LÜCKE Andreas
Published: April 2011

Carbon isotope (δ13Corg) analyses of non‐marine clastic rocks and neritic carbonates and black shales spanning the Silurian/Devonian transition are compared from two richly fossiliferous sequences in Qujing of East Yunnan and Zoige of Sichuan, South China. The two sections, Xishancun and Putonggou sections in South China, reveal positive δ13Corg shifts happening in the Upper Pridoli and Lower Devonian and reaching peak values as heavy as –25.2%‰ (Xishancun) and –19.9%‰ (Putonggou) in the lowermost Lochkovian following the first occurrence of the thelodont Parathelodus and the conodont Icriodus woschmidti woschmidti (only in Putonggou Section and together with Protathyris‐Lanceomyonia brachiopod fauna). These results replicate a globally known positive shift in δ13Corg from the uppermost Silurian to the lowermost Devonian. The δ13Corg variations across the Silurian/Devonian Boundary (SDB) at the two sections in South China exhibit a shift in carbon isotopic composition similar to the detailed SDB curves from the borehole Klonk‐1 drilled at top of the Klonk Global Standard Stratotype‐Section and Point (GSSP) in the Prague Basin, Czech Republic. In addition, four microvertebrate assemblages, including the Liaojiaoshan, Xishancun, Yanglugou and Xiaputonggou assemblages, are recognized from the Silurian/Devonian transition exposed in the Xishancun and Putonggou sections, respectively. The results from both carbon isotope stratigraphy and microvertebrate assemblage sequences suggest that the SDB in South China is located at the base of the Xishancun Formation (between sample QX‐20 and sample QX‐21) in the Xishancun Section and the lower part of the Xiaputonggou Formation (between sample ZP‐09 and sample ZP‐10) in the Putonggou Section. The isotopic trend for organic carbon together with the changes of microvertebrate remains across the SDB can offer an approach to a potential correlation of the SDB from different sedimentary facies, which help to correlate the marine with non‐marine deposits.
Correlation of the Tournaisian‐Visean Boundary Beds
Authors: HOU Hongfei , WU Xianghe , YIN Bao'an
Published: April 2011

With the definition and adoption of the Global Stratotype Section and Point (GSSP) for base of the Visean in China, the newly synthesized zonations and correlation of some significant fossil groups: foraminifera, conodont, coral and brachiopoda near the Tournaisian‐Visean boundary beds are reviewed, which help in the recognition of the boundary in various sedimentary facies. The occurrence of two physical events, one pre‐ and one post‐ the Tournaisian‐Visean boundary is emphasized, which allows for recognition of the position close to the Tournaisian‐Visean boundary in the field. The regional correlation in southern China and international correlation throughout Eurasia around the Tournaisian‐Visean boundary beds with the GSSP is proposed.
Lithologic Boundaries in Permian Post‐glacial Sediments of the Gondwana‐affinity Regions of China: Typical Sections, Age Range and Correlation
Authors: JIN Xiaochi , HUANG Hao , SHI Yukun , ZHAN Lipei
Published: April 2011

In Southwest China, Gondwana‐affinity Permo‐Carboniferous deposits are known to occur in the Northern Himalayas, the Lhasa Block and the South Qiangtang Block, the Baoshan Block and the Tengchong Bock. The three‐fold clastic successions, namely diamictite–pebbly mudstone–dark mudstone and shale are commonly interpreted as representing deposits of glacial–deglacial–post‐glacial periods in marine environments. Deposits, for example, the Dingjiazhai Formation in the Baoshan Block, the Kongshuhe Formation in the Tengchong Block, the Yongzhu Group and the Poindo Group in the Lhasa Block, are all succeeded by carbonate deposits. This marks a significant change from post‐glacial clastic environment to a carbonate environment. Available paleontological data show that the change from post‐glacial clastic environment to carbonate environment took place in the Baoshan, Tengchong and Lhasa Block at the beginning of the Artinskian. The carbonate environment in the Baoshan Block was spoiled by the eruption of the Woniusi Basalts, and in the Xainza area of the Lhasa Block was shortly replaced by clastic environment until the Kungurian. In the northern Himalayas limestones began to occur in the Late Permian in a fluctuating manner.
Progress, Problems and Prospects on the Stratigraphy and Correlation of the Kungurian Stage, Early Permian (Cisuralian) Series
Authors: WANG Yue , WANG Jing , CHEN Jun , WANG Weijie , SHEN Shuzhong , HENDERSON Charles M.
Published: April 2011

The Kungurian Stage is one of the three remaining stages of the Permian that is not yet defined at the base by a Global Stratotype Section and Point (GSSP). The candidate section at the Yuryuzan' River in the Urals yields few conodonts, and contains non‐marine sediments near the boundary. The search for a suitable, continuous marine succession is a principal task for the Subcommission on Permian Stratigraphy. The Leonardian, with its type area in the southwest United States, and in objective stratigraphic succession directly beneath the basal Guadalupian Roadian Stage, has priority to serve as a subseries of the Lower Permian. However, distinct provincialism limits the correlation of Leonardian fossil zones with the fusuline‐based Tethyan timescale. Conodonts can be correlated in many important regions on opposite sides of Pangea, yet contradictions arise when relating conodont zones with fusuline and ammonoid zones. The different taxonomic philosophies are highly suspected for the cause of the conflicts, but also there are different conodonts from the type Roadian in West Texas. Given that the Pamir and Darvaz in central Asia are difficult to access, further investigations should focus on South China, where abundant fusulines and ammonoids facilitate correlation throughout the Tethyan region, and where conodonts permit correlation with North America.
Terrestrial Mio‐Pliocene Boundary in the Linxia Basin, Gansu, China
Authors: DENG Tao , HOU Sukuan , SHI Qinqin , CHEN Shaokun , HE Wen , CHEN Shanqin
Published: April 2011

The Lower Pliocene of the Linxia Basin in Gansu Province is one of only a few representative sections for the Early Pliocene sedimentary records in northern China, and even in East Asia. Recently, abundant mammalian fossils were found from the base of red clays of the Lower Pliocene Hewangjia Formation at Duikang in Guanghe County within this basin. Previously, the Pliocene mammals were sparsely found in China, and most were collected from fluvial and lacustrine deposits in the eastern Loess Plateau. Mammals from the widely distributed Pliocene Hipparion Red Clay are less in number. The known fossils from Duikang include 20 species and belong to the Shilidun Fauna. Their faunal components are similar to the Early Pliocene Gaozhuang Fauna from Yushe, Shanxi. On the other hand, some taxa from Duikang have not been found in the Gaozhuang Fauna, are slightly more primitive in evolutionary level, and appeared mainly in the Late Miocene. As a result, the age of the Duikang fossils may be slightly earlier than that of the Gaozhuang Fauna and closer to the lower boundary of the Pliocene. The Duikang fossiliferous bed is 0.8 m above the top of the Late Miocene Liushu Formation, and the first occurrence of the three‐toed horse Hipparion pater can be regarded as a biostratigraphical marker of the Miocene/Pliocene boundary. In conclusion, Duikang is an ideal candidate locality to establish as the stratotype of the lower boundary of the Chinese terrestrial Pliocene.
A New Species of the Extinct Genus Schizolepis from the Jurassic Daohugou Flora, Inner Mongolia, China with Special Reference to the Fossil Diversity and Evolutionary Implications
Authors: ZHANG Jianwei , D'ROZARIO Ashalata , YAO Jianxin , WU Zhenjie , WANG Lijun
Published: April 2011

Schizolepis daohugouensis sp. nov. is described from the Jurassic sediments of Daohugou flora, from Ningcheng County, Inner Mongolia Autonomous Region, China. The female cone is slender, cylindrical in shape, seed scale complexes are loosely and helically arranged on the cone axis at intervals of 3–5 mm. The seed scales are bilobed and divided almost from the base; the scales have no evident petiole but an articulation at the region of attachment to the cone axis. Each lobe of the seed scales is oval in shape, widest at the lower middle part; lobes are obtusely pointed with entire margins. Bract scale is fan shaped. Based on the records of Schizolepis, this is the first report of the occurrence of female cone of Schizolepis with the seed scales, the winged seeds and vegetative branches preserved together in the Jurassic deposits. The new discovery provides evidence that confirms the phylogenetic position of Schizolepis to the extant Pinaceae.
Two New Fossil Lacewing Species from the Middle Jurassic of Inner Mongolia, China (Neuroptera: Grammolingiidae)
Authors: SHI Chaofan , YANG Qiang , REN Dong
Published: April 2011

Two new species of lacewings are described and illustrated from the Jiulongshan Formation (Middle Jurassic) of Inner Mongolia, China: Leptolingia calonervis sp. nov. and Litholingia ptesa sp. nov. (Grammolingiidae). The species can be distinguished by the following features: the outermost branch of MP2 on the hind wing did not reach the margin of wing in Leptolingia calonervis sp. nov.; the second branch of Rs forked deeply while other branches of Rs forked much later in Litholingia ptesa sp. nov.
What of guidelines for osteoarthritis?
Authors: LIM Anita Y. N. , DOHERTY Michael
Published: April 2011

Osteoarthritis (OA) is by far the most common joint disease and a major cause of pain and disability. The prevalence and impact of OA will increase in the next decades in the Asia‐Pacific region due to increased longevity, increasing urbanization and a parallel increase in obesity. The three main types of evidence to inform evidence‐based practice are research evidence, expert experience and patient opinion – all three of these are equally weighted. Guideline development groups vary in terms of process and structure of guideline production and in how much integration there is between research, expert and patient evidence. Nevertheless, guidelines on OA concur in recommending: holistic assessment of the patient and individualizing the management plan; patient information access; weight loss if overweight or obese, and prescription of exercise. Additional adjunctive non‐pharmacological and pharmacological interventions, including surgery, may be added to this core set as required. However, when audited, it appears that management of OA is often suboptimal, with a major focus on oral analgesics, especially non‐steroidal anti‐inflammatory drugs. A number of barriers to implementation are evident and appropriate audit of care is necessary to improve delivery of service and to plan healthcare resources. For OA, the effect size of placebo in clinical trials is usually far greater than the additional specific effect of individual treatments, emphasizing the importance of contextual (‘meaning’) response in this chronic painful condition. This has important implications for clinical care in that optimization of the contextual response can lead to improvements in patient outcomes even in the absence of very effective treatments.
Inhibition of P‐glycoprotein facilitated glycosaminoglycan accumulation during chondrogenesis of human bone marrow mesenchymal stem cells
Authors: KIM Sang‐Gyung , LEE A‐Jin , LEE Seung Jin , SUH Hun Suk , SHIN Im‐Hee
Published: April 2011

Aim:  P‐glycoprotein (P‐gp) is an adenosine‐5‐triphosphate Binding Cassettes B 1 (ABCB1) transporter that exports various substrates on cellular membrane. Surface expression of P‐gp was decreased during chondrogenesis of human bone marrow mesenchymal stem cells (BM‐MSCs). We examined the role of P‐gp in extracellular matrix deposition during chondrogenesis of human BM‐MSCs.

Method:  BM‐MSCs were isolated from 16 volunteers after informed consent and incubated for 28 days using three‐dimensional culture methods in chondrogenic medium with and without P‐gp inhibitor (verapamil, 10 μmol/L).

Results:  Hematoxylin and eosin staining revealed a cartilaginous structure with chondrogenic cells in the lacunae after 2 weeks of culture. Total glycosaminoglycan (GAG) content was increased and rose during pellet culture. Hyaluronan (HA) content of the culture medium decreased with P‐gp inhibitor. Type II collagen deposition decreased with P‐gp inhibitor.

Conclusion:  Inhibition of P‐gp facilitated GAG accumulation via HA export inhibition during chondrogenic differentiation of human BM‐MSCs. Modulation of P‐gp expression during chondrogenesis would be a possible therapeutic approach for articular cartilage regeneration.
Who should have knee joint replacement surgery for osteoarthritis?
Authors: DIEPPE Paul , LIM Keith , LOHMANDER Stefan
Published: April 2011

Knee joint replacement is an effective and cost‐effective intervention for severe symptomatic osteoarthritis of the knee joint. However, utilisation rates vary hugely, there are no indications, it is difficult to know when (in the course of arthritis) it is best to operate, and some 10–20% of people who have this surgery are unhappy with the outcome, and have persistent pain. In this article we briefly discuss the variations in utilization of knee joint replacement, and then outline four different approaches to the selection and prioritisation of patients for this procedure. Consensus criteria, including appropriateness criteria are available, but if produced by professionals alone, they may conflict with the views of patients and the public. Databases and cohort studies can be used to attempt relating outcomes to baseline characteristics, but at present we can only account for a small percentage of the variance with this technique. Finally, we propose use of the ‘capacity to benefit framework’ to attempt providing guidance to both patients and healthcare professionals.
Physiotherapy management of knee osteoarthritis
Authors: PAGE Carolyn J. , HINMAN Rana S. , BENNELL Kim L.
Published: April 2011

Knee osteoarthritis (OA) is a prevalent chronic joint disease causing pain and disability. Physiotherapy, which encompasses a number of modalities, is a non‐invasive treatment option in the management of OA. This review summarizes the evidence for commonly used physiotherapy interventions. There is strong evidence to show short‐term beneficial effects of exercise on pain and function, although the type of exercise does not seem to influence treatment outcome. Delivery modes, including individual, group or home exercise are all effective, although therapist contact may improve benefits. Attention to improving adherence to exercise is needed to maximize outcomes in the longer‐term. Knee taping applied with the aim of realigning the patella and unloading soft tissues can reduce pain. There is also evidence to support the use of knee braces in people with knee OA. Biomechanical studies show that lateral wedge shoe insoles reduce knee load but clinical trials do not support symptomatic benefits. Recent studies suggest individual shoe characteristics also affect knee load and there is current interest in the effect of modified shoe designs. Manual therapy, while not to be used as a stand‐alone treatment, may be beneficial. In summary, although the research is not equivocal, there is sufficient evidence to indicate that physiotherapy interventions can reduce pain and improve function in those with knee OA.
Osteoarthritis of the knees in the COPCORD world
Authors: HAQ Syed A. , DAVATCHI Fereydoun
Published: April 2011

This paper examines and summarizes data on knee osteoarthritis (AO) in Community Oriented Program For Control Of Rheumatic Disorders (COPCORD) publications. A literature search was made through PubMed, Google, Proceedings of Asia‐Pacific League of Associations for Rheumatology (APLAR) congresses, and Abstracts from APLAR congresses. Data were compiled to examine the prevalence of knee OA and knee pain, sex ratio, urban/rural differences and other risk factors. Data on knee pain and OA were available in a total of 36 COPCORD publications. The pooled prevalence of knee OA was 7.9% in adults above the age of 15 years. It was more common in women. Overweight, squatting and cycling appeared to be modifiable risk factors for knee OA. OA of the knee is the commonest rheumatic disease in studied communities. Further research is needed for identification of its modifiable risk factors and development of strategies for reduction of the community burden of this malady.
Chondrocyte apoptosis: a cause or consequence of osteoarthritis?
Authors: ZAMLI Zaitunnatakhin , SHARIF Mohammed
Published: April 2011

Osteoarthritis (OA) is a degenerative joint disease characterized by articular cartilage degradation and changes in the subchondral bone. Over the last two decades, there has been increasing evidence showing association between cartilage degradation and chondrocyte death, and different types of cell death in cartilage have been reported, including apoptosis and chondroptosis as well as necrosis, but which of these types of cell death predominate in OA is debatable. There are also some methodological difficulties in detecting the specific form of cell death in articular cartilage. Current ‘gold standard’ for detecting chondrocyte death is electron microscopy which suggests that the morphological changes of chondrocytes in OA cartilage are attributed to apoptosis and/or chondroptosis. However, the current literature appears to suggest that classic apoptosis plays an important role in OA; but whether chondrocyte apoptosis is a cause or a result of cartilage degeneration in OA is hotly contested. Studies of suitable animal models, especially longitudinal studies, are needed to address the cause‐and‐effect relationship.
Rb‐Sr and Sm‐Nd isotopic systematics of the lherzolitic shergottite GRV 99027
Authors: LIU Tao , LI Chaofeng , LIN Yangting
Published: April 2011

Abstract– Rb‐Sr and Sm‐Nd isotopic analyses of the lherzolitic shergottite Grove Mountains (GRV) 99027 are reported. GRV 99027 yields a Rb‐Sr mineral isochron age of 177 ± 5 (2σ) Ma and an initial 87Sr/86Sr ratio (ISr) of 0.710364 ± 11 (2σ). Due to larger uncertainties of the Sm‐Nd isotopic data, no Sm‐Nd isochron age was obtained for GRV 99027. The ε143Nd value is estimated approximately +12.2, assuming an age of 177 Ma. The ISr of GRV 99027 is distinguishable from other lherzolitic shergottites, confirming our previous conclusion that it is not paired with them (Lin et al. 2005). The new data of GRV 99027 support the same age of approximately 180 Ma for most lherzolitic shergottites, and fill the small gap of ISr between Allan Hills A77005 and Lewis Cliff 88516 (Borg et al. 2002). All available data are consistent with a single igneous source for the intermediate subgroup of lherzolitic shergottites.
Shock experiments in support of the Lithopanspermia theory: The influence of host rock composition, temperature, and shock pressure on the survival rate of endolithic and epilithic microorganisms
Authors: MEYER Cornelia , FRITZ Jörg , MISGAISKI Martin , STÖFFLER Dieter , ARTEMIEVA Natalia A. , HORNEMANN Ulrich , MOELLER Ralf , De VERA Jean‐Pierre , COCKELL Charles , HORNECK Gerda , OTT Sieglinde , RABBOW Elke
Published: April 2011

Abstract–Shock recovery experiments were performed with an explosive set‐up in which three types of microorganisms embedded in various types of host rocks were exposed to strong shock waves with pressure pulse lengths of lower than 0.5 μs: spores of the bacteriumBacillus subtilis,Xanthoria eleganslichens, and cells of the cyanobacteriumChroococcidiopsissp. 029.In these experiments, three fundamental parameters were systematically varied (1) shock pressures ranging from 5 to 50 GPa, (2) preshock ambient temperature of 293, 233 and 193 K, and (3) the type of host rock, including nonporous igneous rocks (gabbro and dunite as analogs for the Martian shergottites and chassignites, respectively), porous sandstone, rock salt (halite), and a clay‐rich mineral mixture as porous analogs for dry and water‐saturated Martian regolith. The results show that the three parameters have a strong influence on the survival rates of the microorganisms. The most favorable conditions for the impact ejection from Mars for microorganisms would be (1) low porosity host rocks, (2) pressures <10–20 GPa, and (3) low ambient temperature of target rocks during impact. All tested microorganisms were capable of surviving to a certain extent impact ejection in different geological materials under distinct conditions.
Al‐Mg systematics of hibonite‐bearing Ca,Al‐rich inclusions from Ningqiang
Authors: HSU Weibiao , GUAN Yunbin , WANG Ying
Published: April 2011

Abstract– Hibonite‐bearing Ca,Al‐rich inclusions (CAIs) usually occur in CM and CH chondrites and possess petrographic and isotopic characteristics distinctive from other typical CAIs. Despite their highly refractory nature, most hibonite‐bearing CAIs have little or no 26Mg excess (the decay product of 26Al), but do show wide variations of Ca and Ti isotopic anomalies. A few spinel‐hibonite spherules preserve evidence of live 26Al with an inferred 26Al/27Al close to the canonical value. The bimodal distribution of 26Al abundances in hibonite‐bearing CAIs has inspired several interpretations regarding the origin of short‐lived nuclides and the evolution of the solar nebula. Herein we show that hibonite‐bearing CAIs from Ningqiang, an ungrouped carbonaceous chondrite, also provide evidence for a bimodal distribution of 26Al. Two hibonite aggregates and two hibonite‐pyroxene spherules show no 26Mg excesses, corresponding to inferred 26Al/27Al < 8 × 10−6. Two hibonite‐melilite spherules are indistinguishable from each other in terms of chemistry and mineralogy but have different Mg isotopic compositions. Hibonite and melilite in one of them display positive 26Mg excesses (up to 25‰) that are correlated with Al/Mg with an inferred 26Al/27Al of (5.5 ± 0.6) × 10−5. The other one contains normal Mg isotopes with an inferred 26Al/27Al < 3.4 × 10−6. Hibonite in a hibonite‐spinel fragment displays large 26Mg excesses (up to 38‰) that correlate with Al/Mg, with an inferred 26Al/27Al of (4.5 ± 0.8) × 10−5. Prolonged formation duration and thermal alteration of hibonite‐bearing CAIs seem to be inconsistent with petrological and isotopic observations of Ningqiang. Our results support the theory of formation of 26Al‐free/poor hibonite‐bearing CAIs prior to the injection of 26Al into the solar nebula from a nearby stellar source.
Nanoindentation of Soda Lime–Silica Glass: Effect of Loading Rate
Authors: Dey Arjun , Chakraborty Riya , Mukhopadhyay Anoop Kumar
Published: April 2011

Structural and mechanical reliability of glass for both conventional and advanced applications is determined by the rate at which it can deform and sustain externally applied static or dynamic strain at the microstructural length scale. Hence, a large number of nanoindentation experiments were conducted on a thin (∼300 μm) commercial soda lime–silica glass with a 150 nm radius Berkovich tip at a constant load of 10,000 μN as a function of variations in the loading rates in the range of 10–20,000 μN/s. The results showed that the nanohardness of the soda lime–silica glass increased by as much as 74% as the loading rate was increased from 10 to 20,000 μN/s. Further, the presence of serrations in load–depth plots and deformation band formations inside the nanoindentaion cavities were more vividly observed in the nanoindentation experiments conducted at lower loading rates rather than those conducted at higher loading rates. These results are explained in terms of shear stress acting underneath the indenter as well as the time scale of interaction between the nanoindenter and the weak links at local microstructural length scale, which owe their origin to the subtle variations in the composition of the given glass.
Tip Clearance Effect on the Flow Pattern of a Radial Impulse Turbine for Wave Energy Conversion
Authors: Pereiras Bruno , Castro Francisco , el Marjani Abdelatif , Rodríguez Miguel A.
Published: April 2011

Turbines for wave energy conversion have a special feature to be taken into account in the study of the tip leakage flow: These turbines are self-rectifying, which work inside a cyclically bidirectional flow alternatively as an inflow/outflow turbine. The phenomena at the blade tip will be different in these two situations. Moreover, it is necessary to take into account the tip clearance of the guide vanes because it has a significant influence on the rotor performance. A previously developed numerical model has been used for this study. The geometry proposed by Setoguchi et al. (2002, “A Performance Study of a Radial Impulse Turbine for Wave Energy Conversion,” Journal of Power and Energy, 216, pp. 15–22) is used in the model. Three different tip clearance sizes have been simulated to compare the influence of the tip clearance size on the performance. Results show that changing the size of the tip clearance from 0% to 4% of the blade span reduces the turbine maximum efficiency by up to 8%. However, the efficiency reduction is more pronounced when the turbine works as an inflow turbine because the tip clearance effect is more important in the inner part of the rotor, since flow velocities are higher and the relative casing motion is lower. This study achieves its main aim, which is to improve knowledge about the phenomena related to the tip clearance and its influence on the performance of radial impulse turbines.
An Investigation of Turbine Wheelspace Cooling Flow Interactions With a Transonic Hot Gas Path—Part II: CFD Simulations
Authors: Laskowski G. M. , Bunker R. S. , Bailey J. C. , Ledezma G. , Kapetanovic S. , Itzel G. M. , Sullivan M. A. , Farrell T. R.
Published: April 2011

A computational model has been developed to study the mechanisms responsible for hot gas ingestion into the wheel-space cavity of a stationary high pressure turbine (HPT) cascade rig. Simulations were undertaken for the stationary rig described by Bunker et al. (2009, “An Investigation of Turbine Wheelspace Cooling Flow Interactions With a Transonic Hot Gas Path—Part I: Experimental Measurements,” ASME Paper No. GT2009-59237) in a companion paper. The rig consists of five vanes, a wheel-space cavity, and five cylinders that represent the blockage due to the leading edge of the rotor airfoils. The experimental program investigated two cylinder diameters and three clocking positions for a nominal coolant flow rate. Comparisons are made between the computed and measured flow-fields for the smaller of the two cylinders. It is demonstrated that the circumferential variation of pressure established by the vane wake and leading edge bow wave results in an unstable shear layer over the rim seal axial gap (trench) that causes hot gases to ingest for a nominal coolant flow. Steady-state computational fluid dynamics (CFD) simulations did not capture this effect and it was determined that an unsteady analysis was required in order to match the experimental data. Favorable agreement is noted between the time-averaged computed and measured pressure distributions in the circumferential direction both upstream and downstream of the trench, as well as within the trench itself. Furthermore, it is noted that time-averaged buffer cavity effectiveness agrees to within 5% of the experimental data for the cases studied. The validated CFD model is then used to simulate the effect of rotation by rotating the cylinders and disk at rotational rate that scales with a typical engine. A sliding mesh interface is utilized to communicate data between the stator and rotor domains. The stationary cases tend to ingest past the first angel-wing for a nominal coolant flow condition, whereas the effect of rotation helps pressurize the cavity and is responsible for preventing hot gas from entering the buffer cavity.
Exploration of NDE Properties of AMB Supported Rotors for Structural Damage Detection
Authors: Sawicki Jerzy T. , Storozhev Dmitry L. , Lekki John D.
Published: April 2011

This paper addresses self-diagnostic properties of active magnetic bearing (AMB) supported rotors for online detection of the transverse crack on a rotating shaft. In addition to pure levitation, the rotor supporting bearing also serves as an actuator that transforms current signals additionally injected into the control loop into the superimposed specially selected excitation forces into the suspended rotor. These additional excitations induce combination frequencies in the rotor response, providing unique signatures for the presence of crack. The background of theoretical modeling, experimental, and computer simulation results for the AMB supported cracked rotor with self-diagnostic excitation forces are presented and discussed.
An Experimental Investigation of the Nonlinear Response of an Atmospheric Swirl-Stabilized Premixed Flame
Authors: Schimek Sebastian , Moeck Jonas P. , Paschereit Christian Oliver
Published: April 2011

Due to stringent emission restrictions, modern gas turbines mostly rely on lean premixed combustion. Since this combustion mode is susceptible to thermoacoustic instabilities, there is a need for modeling tools with predictive capabilities. Linear network models are able to predict the occurrence of thermoacoustic instabilities but yield no information on the oscillation amplitude. The prediction of the pulsation levels and hence an estimation whether a certain operating condition has to be avoided is only possible if information on the nonlinear flame response is available. Typically, the flame response shows saturation at high forcing amplitudes. A newly constructed atmospheric test rig, specifically designed for the realization of high excitation amplitudes over a broad frequency range, is used to generate extremely high acoustic forcing power with velocity fluctuations of up to 100% of the mean flow. The test rig consists of a generic combustor with a premixed swirl-stabilized natural gas flame, where the upstream part has a variable length to generate adaptive resonances of the acoustic field. The OH∗ chemiluminescence response, with respect to velocity fluctuations at the burner, is measured for various excitation frequencies and amplitudes. From these measurements, an amplitude dependent flame transfer function is obtained. Phase-averaged OH∗ pictures are used to identify changes in the flame shape related to saturation mechanisms. For different frequency regimes, different saturation mechanisms are identified.