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Short Length (short + length)
Selected AbstractsAssociation between ovocalyxin-32 gene haplotypes and eggshell quality traits in an F2 intercross between two chicken lines divergently selected for eggshell strengthANIMAL GENETICS, Issue 5 2010H. Takahashi Summary Broken and cracked eggshells contribute significantly to economic losses in the egg production industry. We previously identified ovocalyxin-32 as a potential gene influencing eggshell traits, by analysing an intercross between two parent lines developed from the same founder population by a two-way selection for eggshell strength with non-destructive deformation (DEF) conducted over 14 generations. We determined the nucleotide sequences of six ovocalyxin-32 exons in the parent individuals and analysed the association between ovocalyxin-32 and eggshell traits in the F2 individuals. We identified three haplotypes (W, M and S) of ovocalyxin-32 in the parent individuals. A mismatch amplification mutation assay was performed to distinguish six diplotype individuals (WW, MM, SS, WM, MS and WS) in the F2 population. The egg weight (EW) of SS-diplotype individuals was significantly higher than that of WW-, WM- and WS-diplotypes. Short length of the egg (SLE) of SS-diplotype individuals was significantly higher than that of WW-, WM- and MS-diplotypes. Long length of the egg (LLE) of SS-diplotype individuals was significantly higher than that of WM- and WS-diplotypes. DEF of WW-diplotype individuals was significantly higher than that of SS-, WM, MS and WM-diplotypes. Haplotypic effect analyses showed significant differences between the W-haplotype and the S-haplotypes in the EW, SLE, LLE and DEF. The DEF of M-haplotype was significantly lower than that of W- and S-haplotypes. These results suggest that S- and M-haplotypes are critical for high quality of eggshells in the F2 population. In conclusion, ovocalyxin-32 is a useful marker of eggshell traits and can be used to develop strategies for improving eggshell traits in commercial layer houses. [source] Symbolic dynamics for identifying similarity between rhythms of ecological time seriesECOLOGY LETTERS, Issue 9 2004Bernard Cazelles Abstract Explaining the associations between animal populations or between population and environmental signals is an important challenge. The time series that quantify animal populations are often complex, nonlinear, noisy and non-stationary. These characteristics may make it inappropriate to use traditional techniques when analysing these time series and their mutual dependencies. Here I propose to use symbolic dynamics and techniques from Information Theory to evaluate the degree of dynamic cohesion between time series fluctuations. The main idea is to check whether two (or more) signals tend to oscillate simultaneously, rising and falling together with the same rhythm. Based on synthetic and real time series, I demonstrate that this method is robust to the presence of noise and to the short length of the analysed time series and gives relevant information about the weak relationships between different series. Furthermore, this method appears as simple as classical cross-correlation and outperforms it in the analysed examples. [source] A parylene-based dual channel micro-electrophoresis system for rapid mutation detection via heteroduplex analysis,ELECTROPHORESIS, Issue 18 2008Sertan Sukas Abstract A new dual channel micro-electrophoresis system for rapid mutation detection based on heteroduplex analysis was designed and implemented. Mutation detection was successfully achieved in a total separation length of 250,,m in less than 3,min for a 590,bp DNA sample harboring a 3,bp mutation causing an amino acid change. Parylene-C was used as the structural material for fabricating the micro-channels as it provides conformal deposition, transparency, biocompatibility, and low background fluorescence without any surface treatment. A new dual channel architecture was derived from the traditional cross-channel layout by forming two identical channels with independent sample loading and waste reservoirs. The control of injected sample volume was accomplished by a new u-turn injection technique with pull-back method. The use of heteroduplex analysis as a mutation detection method on a cross-linked polyacrylamide medium provided accurate mutation detection in an extremely short length and time. The presence of two channels on the microchip offers the opportunity of comparing the sample to be tested with a desired control sample rapidly, which is very critical for the accuracy and reliability of the mutation analyses, especially for clinical and research purposes. [source] Improved resolution with microchip-based enhanced field inversion electrophoresisELECTROPHORESIS, Issue 11 2003Christopher J. Backhouse Abstract We present an improvement of the field inversion electrophoresis (FIE) method in which the passage of sample such as DNA back and forth within a short length of a microchannel can provide a similar resolution to that of a significantly longer microchannel. In constant field FIE the application of an alternating potential (e.g., +/, V) over short periods of time (e.g., several Hz) can provide enhanced separations of DNA fragments. In contrast, the present method consists of a series of separations, each of much longer duration, under high and low fields in such a way that the resolution is enhanced. This method is readily modeled and allows improved resolution to be obtained from extremely short microchannels (e.g., 8 mm) while requiring relatively low applied voltages (e.g., less than 600 V). An additional advantage is that this method can allow for the same equipment to be used in a rapid, low-resolution mode or in a slower, high-resolution mode through what might be referred to as an automated "zoom" capability. We believe that this method may facilitate the integration of microfluidic devices and microelectronic devices by allowing these devices to be of a similar small scale (< 1 cm). [source] Selection for birth date in North Sea haddock and its relation to maternal ageJOURNAL OF ANIMAL ECOLOGY, Issue 2 2005PETER J. WRIGHT Summary 1Birth date can be important to lifetime reproductive success. However, selection for birth date has rarely been addressed in fish, despite the opportunity provided by otolith microstructure. 2This study examined the relationship between maternal age, spawning time and early survivorship in the North Sea haddock stock. Temporal changes in egg production were compared with the birth date distribution of progeny surviving to the demersal phase in 1994, 1996 and 1999, when the age structure of the spawning stock differed. 3Estimates of intra-annual variation in stock egg production indicated that first-time spawning 2-year-olds began spawning much later than older age-classes. 4The form and magnitude of selection on birth date varied between years, indicating that the production of multiple batches of eggs over an extended period has some adaptive significance to progeny survival. 5Survivorship was consistently poor from the late spawning period when age 2 females contributed most to stock egg production. This persistent selection against late hatched offspring could reflect either low parental investment, as age 2 females produce smaller eggs, or the short length of the growing season prior to settlement. 6Variability in birth date selection, particularly with respect to first vs. subsequent years of spawning, implies a strong selection pressure for a long reproductive lifespan. As such, reproductive potential in this and other exploited fish species with a similar reproductive trait may have been affected adversely by the general decline in repeat spawning females in recent years. [source] Modelling cellular senescence as a result of telomere stateAGING CELL, Issue 3 2003Carole J. Proctor Summary Telomeres in mammalian cells end in large duplex T loops. These loops protect the single-strand overhangs from degradation and/or interactions with signalling proteins. This protection is sometimes referred to as capping. At each cell division, telomeres shorten and there is a general consensus that telomere shortening triggers cell cycle exit. However, the exact mechanism by which telomere shortening causes cell cycle arrest is not known. Mathematical models of telomere shortening have been developed to help us understand the processes involved. Until now most models have assumed that the trigger for cell cycle arrest is the first telomere or a group of telomeres reaching a critically short length. However, there is evidence that cells stop cycling over a wide range of telomere lengths. This suggests that telomere length per se may not in fact be the trigger for cellular senescence. In this paper we develop a model which examines the hypothesis that uncapping of a telomere is the main trigger. By letting the probability of uncapping depend upon telomere length, we show that the hypothesized model provides a good fit to experimental data. [source] Different mechanisms of action of antimicrobial peptides: insights from fluorescence spectroscopy experiments and molecular dynamics simulations,JOURNAL OF PEPTIDE SCIENCE, Issue 9 2009Gianfranco Bocchinfuso Abstract Most antimicrobial peptides exert their activity by interacting with bacterial membranes, thus perturbing their permeability. They are investigated as a possible solution to the insurgence of bacteria resistant to the presently available antibiotic drugs. However, several different models have been proposed for their mechanism of membrane perturbation, and the molecular details of this process are still debated. Here, we compare fluorescence spectroscopy experiments and molecular dynamics (MD) simulations regarding the association with lipid bilayers and lipid perturbation for two different amphiphilic helical antimicrobial peptides, PMAP-23 and trichogin GA IV. PMAP-23, a cationic peptide member of the cathelicidin family, is considered to induce membrane permeability according to the Shai-Matsuzaki-Huang "carpet" model, while trichogin GA IV is a neutral peptide, member of the peptaibol family. Although several lines of evidence suggest a "barrel-stave" mechanism of pore formation for the latter peptide, its length is only half the normal thickness of a lipid bilayer. Both fluorescence spectroscopy experiments and MD simulations indicated that PMAP-23 associates with membranes close to their surface and parallel to it, and in this arrangement it causes a severe perturbation to the bilayer, both regarding its surface tension and lipid order. By contrast, trichogin GA IV can undergo a transition from a surface-bound state to a transmembrane orientation. In the first arrangement, it does not cause any strong membrane perturbation, while in the second orientation it might be able to span the bilayer from one side to the other, despite its relatively short length, by causing a significant thinning of the membrane. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd. [source] A CANDID ASSESSMENT OF SYSTEMATICS IN THE LAMINARIALES: MUDDLED MORPHOLOGIES AND SKETCHY SEQUENCESJOURNAL OF PHYCOLOGY, Issue 2000G.W. Saunders Algae of the Alariaceae, Laminariaceae and Lessoniaceae are the largest, most complex, and, arguably, most fascinating of the seaweeds. It is, therefore, a profound paradox that these species remain in taxonomic chaos despite the contemporary emphases on systematics. Setchell and Gardner established the classification system in 1925, recognizing these families on the basis of clear morphological features. At that time, however, they acknowledged that some species had features consistent with placement in two families, or that obscured logical placement in any of the families. Ironically, the problems noted by Setchell and Gardner have been ignored and the system has become entrenched in kelp literature. Initial molecular studies highlighted the shortcomings noted by Setchell and Gardner, and further indicated that little of the morphology-based system was natural. It was obvious that the diagnostic morphological features, presence or absence of sporophylls and ontogenetic splitting, were ,noisy' being gained and lost independently many times in kelp evolution. Despite the insights of the initial molecular studies, they had limitations and key relationships remained unresolved. The investigations used the Internal Transcribed Spacers (ITS) of the ribosomal cistron that have phylogenetic limitations owing to their short length, which is exacerbated by the many variable regions that can't be aligned confidently and must be removed prior to phylogenetic analyses. Many molecular publications have appeared subsequent to the first ITS results, and their contribution towards elucidating kelp phylogeny will be assessed. Current investigations using the Large Subunit ribosomal DNA (LSU) for kelp systematics will also be discussed. [source] Composite paraganglioma,ganglioneuroma of the urinary bladderPATHOLOGY INTERNATIONAL, Issue 9 2005Hiroyuki Usuda Presented herein is the case of a 73-year-old man, complaining of dysuria, who had a composite paraganglioma,ganglioneuroma of the urinary bladder (CPGUB). At cystoscopy a submucosal tumor was found in the urinary bladder and resected after transurethral biopsy. The levels of serum catecholamine and 24 h urinary excretion of catecholamine and vanillylmandelic acid were elevated. Grossly, the resected tumor, measuring 4 × 3 × 2.5 cm, had a brownish cut surface with no necrosis and hemorrhage. Histologically, the tumor had alternating cellular and fibrous areas. The cellular areas consisted of polygonal cells, arranged in well-defined nests (Zellballen) and positive for Grimelius staining, with abundant amphophilic to acidophilic cytoplasm, occasionally containing eosinophilic hyaline globules and brown pigments. Although the nuclei of several polygonal cells were bizarre, mitoses and vascular invasion were not found. Fibrous areas consisted of spindle cells, resembling Schwann cell, admixed with ganglionic cells. To the authors' knowledge, only four cases of CPGUB have been reported in the English-language literature. Detailed reported cases and the present case showed no malignant features, such as extra-bladder infiltration and metastasis, and no recurrence in the short length of follow up. Accumulation of long-term follow-up cases may provide valuable prognostic information on this composite tumor. [source] Extraction and characterization of natural cellulose fibers from common milkweed stemsPOLYMER ENGINEERING & SCIENCE, Issue 11 2009Narendra Reddy Natural cellulose fibers with cellulose content, strength, and elongation higher than that of milkweed floss and between that of cotton and linen have been obtained from the stems of common milkweed plants. Although milkweed floss is a unique natural cellulose fiber with low density, the short length and low elongation make milkweed floss unsuitable as a textile fiber. The possibility of using the stems of milkweed plant as a source for natural cellulose fibers was explored in this research. Natural cellulose fibers extracted from milkweed stems have been characterized for their composition, structure, and properties. Fibers obtained from milkweed stems have about 75% cellulose, higher than the cellulose in milkweed floss but lower than that in cotton and linen. Milkweed stem fibers have low % crystallinity when compared with cotton and linen but the strength of the fibers is similar to cotton and elongation is higher than that of linen fibers. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers [source] Mapping of quantitative trait loci affecting eggshell quality on chromosome 9 in an F2 intercross between two chicken lines divergently selected for eggshell strengthANIMAL GENETICS, Issue 5 2009H. Takahashi Summary Broken and cracked eggshells are major causes of significant economic losses to the egg production industry. The quantitative trait loci (QTL) on chromosome 9 influencing the quality of eggshells were identified by analysing an intercross between two parent lines developed from the same founder population by a two-way selection for eggshell strength with non-destructive deformation conducted over 14 generations. Chromosome-wide highly significant (P < 0.01) QTL associated with egg weight (EW), short length of egg (SLE), long length of egg (LLE) and eggshell weight were mapped to the distal region of chromosome 9. Among the QTL affecting EW, SLE and LLE, ovocalyxin-32 was identified as a potential candidate gene influencing eggshell traits. Marker-assisted selection based on these QTL could be used to develop strategies for reducing the breakage and cracking of eggs in commercial layer houses. [source] Serum levels of IGF1 are a useful predictor of retinopathy of prematurityACTA PAEDIATRICA, Issue 4 2010A Pérez-Muñuzuri Abstract Objective:, To ascertain whether insulin-like growth factor 1 (IGF1) is associated with retinopathy of prematurity (ROP) and is a useful predictor of the disease. Although its aetiopathogenesis is multifactorial, development of the disease appears to be related to a deficiency in IGF1, a hormone that acts together with vascular endothelial growth factor in the normal angiogenesis in the retina. Design:, Prospective study for a 30-month period. Participants:, A total of 74 premature newborn babies, of less than 1500 g and/or 32 weeks' gestational age or less. Testing:, To determine the development and severity of ROP. Main outcome measures:, Serum levels of IGF1 were measured once a week from birth until 40 weeks corrected gestational age in each subject. Results:, Of our subjects, 32.4% developed some form of ROP, and all those ROP patients had the following characteristics at birth (median ± standard deviation scores): low weight (1098 ± 188 vs. 1393 ± 285 g), short length (36.74 ± 1.77 vs. 38.89 ± 3.08 cm), small cranial perimeter (26.03 ± 1.74 vs. 27.93 ± 1.81 cm) and young gestational age (29.7 ± 1.78 vs. 31.3 ± 1.79 weeks) (p < 0.05). Other factors previously associated with ROP that were also observed with statistically significant frequency in our ROP patients were bronchopulmonary dysplasia, intracranial haemorrhage, the need for erythrocyte transfusion or treatment with erythropoietin and sepsis (all p < 0.05). Levels of IGF1 at the 3rd week post-partum, independent of gestational age at birth, were clearly lower in the group who developed ROP (29.13 vs. 43.16 ng/mL, p < 0.05). A value of 30 ng/mL of IGF1 in the third week post-partum was found to have a 90% sensitivity in the diagnosis of ROP. A rapid rise in IGF1 levels between the 3rd and 5th weeks appeared to be related to the development of a higher stage of ROP. Conclusion: Determination of IGF1 serum levels in the 3rd week post-partum, independent of gestational age at birth, provides a sufficient and reliable prognostic tool and allows the identification of a group of patients at high risk of developing the disease. [source] Five-Year Survival Distributions of Short-Length (10 mm or less) Machined-Surfaced and Osseotite® ImplantsCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2004Sylvan Feldman DDS ABSTRACT Background: In cases of reduced alveolar bone height, implants of short length (10 mm or less) may be employed although there is a perceived risk that because of their small stature they will be unable to tolerate occlusal loads and will fail to osseointegrate. Purpose: This report describes an analysis of prospective multicenter clinical studies evaluating the risk for failure of short-length implants, comparing dual acid-etched (DAE) Osseotite® implants (Implant Innovations, Inc., Palm Beach Gardens, FL, USA) to machined-surfaced implants. Materials and Methods: Admission criteria were the same for both data sets. Baseline variables of demographics including age, gender and smoking status, bone quality, location, implant dimensions, and types of prostheses were compared to ensure balance among groups. Cumulative survival rates (CSRs) were calculated with the Kaplan-Meier estimator. Results: The implant data included 2,294 implants for the DAE series and 2,597 implants for the machined-surfaced series. Patient demographics showed similar percentages of occurrence for all variables. The distributions of implants between short- and standard-length data sets for baseline variables including width, location, and restorative type were similar, qualifying these data sets for comparison of the independent variable of length. Overall, there was a 2.2% difference in 5-year CSRs between the machined-surfaced short- and the standard-length implants. For these implants a 7.1% difference was observed in the posterior maxilla and an 8.5% difference in the anterior maxilla. For DAE implants the overall difference between "standards" and "shorts" was 0.7%, which is not statistically significant. Conclusion: In this analysis the difference in CSRs between short- and standard-length implants was greater for machined-surfaced implants than for DAE implants. [source] Exploring therapeutic alliance in brief inpatient psychotherapy: a preliminary studyCLINICAL PSYCHOLOGY AND PSYCHOTHERAPY (AN INTERNATIONAL JOURNAL OF THEORY & PRACTICE), Issue 5 2010Mark A. Blais Abstract Background: Therapeutic alliance is one of the most widely investigated variables in psychotherapy research but few studies have explored its role in inpatient psychotherapy. Many factors likely contribute to the lack of inpatient alliance research including the short length of hospital stays, complexity of patient psychopathology and the burdensome quality of most alliance scales. This paper reports on the development and initial application of two comparable brief scales designed to capture patient and therapist alliance ratings. Method: Participants were 20 patients receiving supportive,expressive inpatient psychotherapy. The patients were predominantly depressed women. Baseline measures of distress, symptom severity and functioning were obtained at the first and third sessions. Measures of alliance were obtained at the second session. Results: The brief alliance scales demonstrated adequate internal consistency and the individual items had good adjusted item-to-scale correlations. Consistent with the broad alliance literature, we found that patients rated alliance higher than therapists, patient and therapist alliance ratings were not significantly correlated, and level of functioning was significantly associated with both patients and therapists' alliance ratings. The perceived depth of psychotherapy was also significantly associated with alliance. Unexpectedly, alliance ratings were also negatively associated with improvement during hospitalization. Conclusions: Overall, the study demonstrates both the feasibility and potential benefit of conducting inpatient psychotherapy research.,Copyright © 2009 John Wiley & Sons, Ltd. Key Practitioner Message: This paper shows that inpatient psychotherapy can be studied and potentially improved through the application of brief targeted instruments. [source] Force,frequency and force,length properties in skeletal muscle following unilateral focal ischaemic insult in a rat modelACTA PHYSIOLOGICA, Issue 3 2009G. N. Dormer Abstract Aim:, Our purpose was to quantify skeletal muscle properties following unilateral focal ischaemic insult (stroke) in a rat model. Methods:, Male rats were divided into two groups: stroke and 2 weeks recovery (n = 8) and control group (n = 7). Stroke was induced in the area of the motor neocortex containing hind limb corticospinal neurones. Contractile properties of the medial gastrocnemius muscle were measured in situ in both limbs. Force,length and force,frequency properties were measured before and 35 min after 5 min fatiguing stimulation. Results:, Stroke resulted in bilateral tetanic fade during 200 Hz stimulation. When normalized to 100 Hz contractions, force at 200 Hz was 95.4 ± 0.9% for the paretic muscles, 96.7 ± 1.7% for non-paretic muscles and 102.2 ± 1.0% for muscles of control rats (P = 0.006). Prior to fatiguing contractions, there was no difference in the length dependence of force. During repetitive contractions, active force fell significantly to 19 ± 4 and 25 ± 5% of initial force in paretic and non-paretic muscles of animals with a stroke respectively. In control animals active force fell to 37 ± 5%. During repetitive contractions, fusion index increased in muscles of stroke animals to 1.0 ± 0 but in control animals it was 0.95 ± 0.02. There was selective force depression at short lengths for fatigued paretic muscle (significant difference at muscle lengths less than reference length ,2 mm). Conclusion:, The tetanic fade at high stimulation frequencies indicates that there may be activation failure following focal ischaemic insult. The greater magnitude of fatigue and selective depression at short lengths following repetitive contractions should be investigated further. [source] Diversity in conducting cells in early land plants and comparisons with extant bryophytesBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 3 2003D. EDWARDS Anatomical screening using scanning electron microscopy (SEM) of short lengths of smooth coalified axes (mesofossils) from a Lochkovian (Lower Devonian) locality in the Welsh Borderland, Shropshire has revealed extensive diversity in the architecture of centrally aggregated, elongate cells. At least 14 types have been discovered, each distinguished by variation in wall architecture and combination of the cells in the central strand. End walls have not been seen. These elongate cells may have smooth, uniformly thick or thin walls, walls with smooth projections either traversing or lining the lumen, or bilayered walls, the innermost perforated by pores of plasmodesmata dimensions. The latter type may be further divided on presence or absence of projections which may line the lumen, but usually cross it and are highly disorganized. Indeed, none of the cells shows the regularity associated with the secondary thickenings of tracheids, but the imperforate/pitted forms with projections superficially resemble the S-type tracheids of the Rhyniopsida in basic construction. Simply pitted types show greater similarity with the water-conducting cells (WCCs) of liverworts and Takakia. To facilitate direct comparison with bryophyte conducting elements, SEM studies were undertaken on the WCCs of a number of mosses and liverworts and on the leptoids of mosses, in conjunction with a range of degradation experiments designed to assess the fossilization potential of these cells. With the exception of polytrichaceous hydroids, the latter demonstrated the resilience of hydroids and leptoids to the chemical treatments. In addition, dehydration of the leptoids produced globular residues similar to those seen in some of the fossils. This combination of techniques raises the possibility that food-conducting cells might well be preserved in coalified fossils, and hence extends the interpretation of the functions of the elongate cells. Broadly speaking, imperforate bilayered examples may have been involved in water conduction, cells with globular residues with or without pitting involved in metabolite movement, and smooth walled examples with or without projections involved in support. The wider affinities of the plants which produced the axes remain equivocal and in the absence of sporangia it is impossible to assign them to a genus. However, this anatomical diversity in vegetative remains of extreme simplicity demonstrates far greater diversity in early land vegetation than is apparent from perusal of species lists. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 141, 297,347. [source] | |||||||||||||