Journal articles on the topic 'Shape factor b'
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Riddihough, G. "Transcription factor shape-shifts DNA." Science 349, no. 6250 (August 20, 2015): 838. http://dx.doi.org/10.1126/science.349.6250.838-b.
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MATSUDAIRA, Mitsuo, Tomoe MASUDA, Minami WADA, and Hiroko YOKURA. "Shape Factor of Flared Skirts Compared with That of Circular Fabrics ." Journal of Textile Engineering 61, no. 6 (2015): 69–73. http://dx.doi.org/10.4188/jte.61.69.
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Becher, Thomas, and Richard J. Hill. "Comment on form-factor shape and extraction of |Vub| from B→πlν." Physics Letters B 633, no. 1 (February 2006): 61–69. http://dx.doi.org/10.1016/j.physletb.2005.11.063.
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Croitoru, Dorin Cătălin, Aurelian Adrian Baciu, and Bianca Ionela Pătraşcu. "Results Regard Productivity Of Some Quince Varieties Cultivated In Northern Oltenia Area Depending Of The Arhitectural Elements Of The Trees Crown." ACTA Universitatis Cibiniensis 67, no. 1 (September 1, 2015): 162–67. http://dx.doi.org/10.1515/aucts-2015-0083.
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Abstract Experimental area is located on the third terrace of the Jiu River at the altitude of 383 m in the northern part of Targu-Jiu City on the experimental plantations established in 1987 at Targu-Jiu Fruit-Growing Research and Production Station. Considering the favourable area of the quince culture in Northern Oltenia an experience was placed under the conditions for intensive plantations for zoned varieties. The variety and crown shape are important factors in the intensive cultivation of quince. The experience was placed after the subdivided parcels method with two factors being the type 4 × 5 in three repetitions. The studied factors:- Factor - shaped crown with four graduations - late flat bowl, simple palm, shapeless hedge, bush trunk - Factor B - 5 varieties of quince graduations Aurii, Aromate, Moldoveneşti, De Constantinopol, De Portugalia Results obtained in the three years of study 2012 - 2014 emphasize the superiority of crown shape and variety Moldoveneşti vessel flattened late in terms of quantity and quality of fruit.
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Wei, Sheng-cai, Liang Xu, Wan-hu Li, Yun Li, Shou-fang Guo, Xiao-rong Sun, and Wen-wu Li. "Risk stratification in GIST: shape quantification with CT is a predictive factor." European Radiology 30, no. 4 (January 3, 2020): 1856–65. http://dx.doi.org/10.1007/s00330-019-06561-6.
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Abstract Background Tumor shape is strongly associated with some tumor’s genomic subtypes and patient outcomes. Our purpose is to find the relationship between risk stratification and the shape of GISTs. Methods A total of 101 patients with primary GISTs were confirmed by pathology and immunohistochemistry and underwent enhanced CT examination. All lesions’ pathologic sizes were 1 to 10 cm. Points A and B were the extremities of the longest diameter (LD) of the tumor and points C and D the extremities of the small axis, which was the longest diameter perpendicular to AB. The four angles of the quadrangle ABCD were measured and each angle named by its summit (A, B, C, D). For regular lesions, we took angles A and B as big angle (BiA) and small angle (SmA). For irregular lesions, we compared A/B ratio and D/C ratio and selected the larger ratio for analysis. The chi-square test, t test, ROC analysis, and hierarchical or binary logistic regression analysis were used to analyze the data. Results The BiA/SmA ratio was an independent predictor for risk level of GISTs (p = 0.019). With threshold of BiA at 90.5°, BiA/SmA ratio at 1.35 and LD at 6.15 cm, the sensitivities for high-risk GISTs were 82.4%, 85.3%, and 83.8%, respectively; the specificities were 87.1%, 71%, and 77.4%, respectively; and the AUCs were 0.852, 0.818, and 0.844, respectively. LD could not effectively distinguish between intermediate-risk and high-risk GISTs, but BiA could (p < 0.05). Shape and Ki-67 were independent predictors of the mitotic value (p = 0.036 and p < 0.001, respectively), and the accuracy was 87.8%. Conclusions Quantifying tumor shape has better predictive efficacy than LD in predicting the risk level and mitotic value of GISTs, especially for high-risk grading and mitotic value > 5/50HPF. Key Points • The BiA/SmA ratio was an independent predictor affecting the risk level of GISTs. LD could not effectively distinguish between intermediate-risk and high-risk GISTs, but BiA could. • Shape and Ki-67 were independent predictors of the mitotic value. • The method for quantifying the tumor shape has better predictive efficacy than LD in predicting the risk level and mitotic value of GISTs.
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Rand-Giovannetti, Devin, David C. Cicero, Jonathan M. Mond, and Janet D. Latner. "Psychometric Properties of the Eating Disorder Examination–Questionnaire (EDE-Q): A Confirmatory Factor Analysis and Assessment of Measurement Invariance by Sex." Assessment 27, no. 1 (November 2, 2017): 164–77. http://dx.doi.org/10.1177/1073191117738046.
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The original, theoretically derived factor structure of the Eating Disorder Examination–Questionnaire (EDE-Q) has received limited empirical support and there is no consensus on an appropriate alternative. Moreover, there is a paucity of data on the factor structure of the EDE-Q across sexes. The goals of the current study were to evaluate models of the EDE-Q factor structure and to assess the best-fitting model for differences by sex. Twelve models were compared using confirmatory factor analysis in a sample of 940 undergraduates. Confirmatory factor analysis did not support the original factor structure. A four-factor model fit the data reasonably well with factors corresponding to themes of (a) dietary restraint, (b) preoccupation and restriction, (c) weight and shape concern, and (d) eating shame. The EDE-Q was found to be invariant by sex across all factors except Factor 3. The implications of these findings are discussed.
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Libois, Q., G. Picard, J. L. France, L. Arnaud, M. Dumont, C. M. Carmagnola, and M. D. King. "Influence of grain shape on light penetration in snow." Cryosphere 7, no. 6 (November 26, 2013): 1803–18. http://dx.doi.org/10.5194/tc-7-1803-2013.
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Abstract. The energy budget and the photochemistry of a snowpack depend greatly on the penetration of solar radiation in snow. Below the snow surface, spectral irradiance decreases exponentially with depth with a decay constant called the asymptotic flux extinction coefficient. As with the albedo of the snowpack, the asymptotic flux extinction coefficient depends on snow grain shape. While representing snow by a collection of spherical particles has been successful in the numerical computation of albedo, such a description poorly explains the decrease of irradiance in snow with depth. Here we explore the limits of the spherical representation. Under the assumption of geometric optics and weak absorption by snow, the grain shape can be simply described by two parameters: the absorption enhancement parameter B and the geometric asymmetry factor gG. Theoretical calculations show that the albedo depends on the ratio B/(1-gG) and the asymptotic flux extinction coefficient depends on the product B(1-gG). To understand the influence of grain shape, the values of B and gG are calculated for a variety of simple geometric shapes using ray tracing simulations. The results show that B and (1-gG) generally covary so that the asymptotic flux extinction coefficient exhibits larger sensitivity to the grain shape than albedo. In particular it is found that spherical grains propagate light deeper than any other investigated shape. In a second step, we developed a method to estimate B from optical measurements in snow. A multi-layer, two-stream, radiative transfer model, with explicit grain shape dependence, is used to retrieve values of the B parameter of snow by comparing the model to joint measurements of reflectance and irradiance profiles. Such measurements were performed in Antarctica and in the Alps yielding estimates of B between 0.8 and 2.0. In addition, values of B were estimated from various measurements found in the literature, leading to a wider range of values (1.0–9.9) which may be partially explained by the limited accuracy of the data. This work highlights the large variety of snow microstructure and experimentally demonstrates that spherical grains, with B = 1.25, are inappropriate to model irradiance profiles in snow, an important result that should be considered in further studies dedicated to subsurface absorption of short-wave radiation and snow photochemistry.
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Wang, C. N., J. R. Chang, and W. C. Chang. "Influences of Diaphragm Materials on the Performance of a Microspeaker." Journal of Mechanics 31, no. 3 (April 10, 2015): 331–36. http://dx.doi.org/10.1017/jmech.2015.4.
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ABSTRACTThe purpose of this study was to investigate the influence of a diaphragm material on the performance of a microspeaker. The finite element method was adopted to analyze the mode shapes and the displacement of the diaphragm under a force load. The Rayleigh integral was then calculated to determine the radiated sound pressure and frequency response of a loudspeaker. The location of the voice coil was also investigated. Locating the voice coil at approximately 53% to 76% of coil-radius/diaphragm-radius ratio yielded a favorable mode shape distribution and performance for the loudspeaker. In addition, two loudspeaker designs, Models A and B, were analyzed to determine the effects of the diaphragm material. The numerical results of Models A and B, indicated that the mode shape is a crucial factor when considering the materials used in a loudspeaker diaphragm. The property of a material at the inflection point of a mode shape obviously affects the modal frequency. According to this observation, the most crucial first and second axial symmetric modes in a loudspeaker design can be adjusted and the performance can be improved.
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Mani, M. Radhika, and T. Srikanth. "An Innovative Vortex based Complex Potential Signature for Shape based Object Recognition." International Journal of Computational and Applied Mathematics & Computer Science 2 (June 4, 2022): 39–43. http://dx.doi.org/10.37394/232028.2022.2.8.
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An Innovative approach for representation and description of shape components for object recognition based on complex potential is proposed. In the complex plane, the flow of velocity is a crucial factor to discriminate different shapes. Hence, the present paper computes the potential flow by transforming the shape of the input object into complex plane. The present paper computes the Vortex based Complex Potential signature (VCP) by considering the radial lines as Equipotential lines and the circles as streamlines. The proposed VCP signature is described with the Fourier transformation for the generation of feature vector. The Chebyshev distance measure is used in the shape toning stage. The efficiency of the proposed descriptor is evaluated with the MPEG-CE-1 Set B database. The results prove the competency of the proposed descriptor than the benchmark descriptors
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Noutfia, Younés, and Ewa Ropelewska. "Comprehensive Characterization of Date Palm Fruit ‘Mejhoul’ (Phoenix dactylifera L.) Using Image Analysis and Quality Attribute Measurements." Agriculture 13, no. 1 (December 27, 2022): 74. http://dx.doi.org/10.3390/agriculture13010074.
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An in-depth determination of date fruit properties belonging to a given variety can have an impact on their consumption, processing, and storage. The objective of this study was to characterize date fruits of the ‘Mejhoul’ variety using (i) objective and non-destructive image-analysis features and (ii) measurements of physicochemical parameters. Based on images acquired using a digital camera, more than 1600 texture parameters from the individual color channels L, a, b, R, G, B, X, Y, and Z, and 40 geometric characteristics (including linear dimensions and shape factors for each fruit), were determined. Additionally, pomological features, water content, water activity, color parameters (L*, a*, b*), total soluble solids (TSS), reducing sugars, and total sugars were measured. As a main result, the application of machine vision allowed for the correct detection of ‘Mejhoul’ dates and the determination of the image features. The differences in the values of the histogram’s mean (HMean texture) for individual color channels were determined. The ‘Mejhoul’ date fruit images in color channel a (aHMean equal to 145.88) and color channel b (bHMean: 145.49) were the brightest, and in channel Z they were the darkest (ZHMean: 4.23). Due to the determination of the elliptic shape factor (W1) of 1.000 and the circular shape factor (W2) of 0.110, the elliptical shape of the fruit was confirmed. On the other hand, ‘Mejhoul’ dates were characterized by a length of 47.3 mm, a diameter of 26.4 mm, flesh thickness of 6.25 mm, total soluble solids of 62.1%, water content of 28.0%, water activity of 0.652, hardness of 694 g, reducing sugars of 13.8%, and total sugars of 58.8%. Due to the determination of many image features and other parameters, this paper presents the first comprehensive characterization of ‘Mejhoul’ date fruits using a non-destructive imaging technique linked to some physicochemical quality attributes.
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Betti, Michele, Luciano Galano, Michele Petracchi, and Andrea Vignoli. "Diagonal cracking shear strength of unreinforced masonry panels: a correction proposal of the b shape factor." Bulletin of Earthquake Engineering 13, no. 10 (April 21, 2015): 3151–86. http://dx.doi.org/10.1007/s10518-015-9756-8.
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Kim, K. S. "A Stress Intensity Factor Tracer." Journal of Applied Mechanics 52, no. 2 (June 1, 1985): 291–97. http://dx.doi.org/10.1115/1.3169043.
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A new optical method, Stress Intensity Factor Tracer (SIFT), has been developed. The device measures continuously the real-time stress intensity factor variation, K1(t), of a moving crack tip using a single, stationary photodetector. The method uses the fact that any variation in K1(t) leads to a change in the intensity of light, I(t), impinging on a fixed finite area, Γ, on the focal plane. The focal plane is defined as the plane on which initially parallel light rays transmitted through a transparent fracture specimen (or reflected from the surface of an opaque specimen) are focused by a converging lens. Provided that the light detecting area, Γ, excludes the focal point, a simple relation, I(t) =B[K1(t)]4/3, has been obtained for a K1-dominant field. The constant, B, is a product of several experimental parameters including a “shape factor” of the sampling area, Γ, where I(t) is measured. A significant feature of this method is that I(t) is independent of the location of the crack tip in the illuminated zone on the specimen plane. The technique may therefore be applied to dynamic fracture studies without using high-speed photography. Only the constant, B, becomes a function of crack velocity for the dynamic K1-field. This paper presents the theoretical development of the SIFT method, including the wave optics of the system. Experimental results supporting the theory are included.
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Wang, Aizeng, and Gang Zhao. "Curvature variation factor and its application." International Journal of Wavelets, Multiresolution and Information Processing 15, no. 02 (February 7, 2017): 1750013. http://dx.doi.org/10.1142/s0219691317500138.
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Evaluation on curvature variation is a significant problem in the field of curve fairing, and traditional evaluation is generally performed by observing curvature plots qualitatively. By using the theory of B-spline wavelet, the concept of curvature variation factor (CVF) is put forth in this paper to describe curvature variation quantitatively. It is verified that the quantitative evaluation results by the CVF method agree well with the traditional qualitative judgments. Based on CVF, a new curve-fairing algorithm is further put forward, whose validness is verified by an example. The advantage of the CVF-based algorithm is that it can realize different fairing effect to meet different requirements under diverse circumstances only by adjusting the shape error.
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Haq, Rois Syarif Qoidhul, Mohammad Imron, and Budi Hascaryo Iskandar. "PERBANDINGAN FAKTOR TEKNIS DESAIN KAPAL BANTUAN DENGAN KAPAL LOKAL ≤ 5GT DI KABUPATEN CILACAP JAWA TENGAH." Marine Fisheries : Journal of Marine Fisheries Technology and Management 11, no. 1 (August 10, 2020): 13–21. http://dx.doi.org/10.29244/jmf.v11i1.30180.
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Fiberglass aid vessels KM. Nelayan 2018 with a size of ≤5 gross tonnage not all can be directly used by local fishermen. Cilacap Regency received 7 aid vessel and it had to renovate. The renovation related to technical design factors, while it is still not yet be reviewed. This study aims to identify and compare differences in technical design factors between the aid vessel and the local vessel. Identification method by direct observation, including measurements of the main dimensions, shape of the hull and bow, general arrangement and working area. The identification data is compared to get the differences. Observation results show that the aid vessel have a ratio of L/D and L/B between local vessel values they are 8,96 from 7,72-9,20 and 13,33 from 12,92-14,11, but have the smallest value at B/D which is 1,49 from 1,51-1,71. The Hulls shape have same type, they are "u-bottom". The shape of the bow and the stern also have the same shape, they are raked bow and transom stern, but height of aid vessel bows is 1,9 m, it is higher than the average of local vessels which only 1,34 m. The height of the engine mount at the stern is also too high at 56 cm, while the average on the local vessel is 53 cm. The general arrangement and working area almost same. The vessel feature, safety and security factors of fishermen need to be improved in aid vessel.
Keywords: feature, fiberglass fishing vessel, technical factor design
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Li, You Tang, Bo Chen, and Rui Feng Wang. "Effect of Friction on the Stress Field Strength of Gear Cracks." Key Engineering Materials 452-453 (November 2010): 493–96. http://dx.doi.org/10.4028/www.scientific.net/kem.452-453.493.
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Based on elasticity theory, the stress field and stress intensity factor of gear crack are discussed. The effect of friction coefficient and crack shape on equivalent stress, displacement at crack tip and stress intensity factor were analyzed by using general finite element software ANSYS, and the formula of stress intensity factor of gear crack was revised. The results showed that the equivalent stress, displacement at crack tip and stress intensity factor increased with the friction coefficient for the same crack. For the same f and different a/c, the front friction surface played a major role when a/B﹤0.05, and the post friction surface played a major role when a/B﹥0.05. The stress intensity factor increase at first, and then decrease with the increase of a/c.
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Dantas Machado, Ana Carolina, Brendon H. Cooper, Xiao Lei, Rosa Di Felice, Lin Chen, and Remo Rohs. "Landscape of DNA binding signatures of myocyte enhancer factor-2B reveals a unique interplay of base and shape readout." Nucleic Acids Research 48, no. 15 (August 1, 2020): 8529–44. http://dx.doi.org/10.1093/nar/gkaa642.
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Abstract Myocyte enhancer factor-2B (MEF2B) has the unique capability of binding to its DNA target sites with a degenerate motif, while still functioning as a gene-specific transcriptional regulator. Identifying its DNA targets is crucial given regulatory roles exerted by members of the MEF2 family and MEF2B’s involvement in B-cell lymphoma. Analyzing structural data and SELEX-seq experimental results, we deduced the DNA sequence and shape determinants of MEF2B target sites on a high-throughput basis in vitro for wild-type and mutant proteins. Quantitative modeling of MEF2B binding affinities and computational simulations exposed the DNA readout mechanisms of MEF2B. The resulting binding signature of MEF2B revealed distinct intricacies of DNA recognition compared to other transcription factors. MEF2B uses base readout at its half-sites combined with shape readout at the center of its degenerate motif, where A-tract polarity dictates nuances of binding. The predominant role of shape readout at the center of the core motif, with most contacts formed in the minor groove, differs from previously observed protein–DNA readout modes. MEF2B, therefore, represents a unique protein for studies of the role of DNA shape in achieving binding specificity. MEF2B–DNA recognition mechanisms are likely representative for other members of the MEF2 family.
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Bassuet, Alban. "New Acoustical Parameters and Visualization Techniques to Analyze the Spatial Distribution of Sound in Music Spaces." Building Acoustics 18, no. 3-4 (December 2011): 329–47. http://dx.doi.org/10.1260/1351-010x.18.3-4.329.
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An important factor in our appreciation of music in a hall is the perception of the spatial distribution of sound, influenced by room shape and form. This paper investigates new techniques for visualizing 3D impulse responses and two new spatial indicators are proposed: LH (ratio of low lateral versus high lateral energy), FR (ratio of front lateral versus rear lateral energy). Different room shape characteristics are illustrated from B-format measurements conducted in a selection of famous music spaces such as old and new recital and concert halls, and sacred music spaces.
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Paraskevopoulou, Mary Th, and Marouan G. Khabbaz. "Influence of Taper of Root Canal Shape on the Intracanal Bacterial Reduction." Open Dentistry Journal 10, no. 1 (October 31, 2016): 568–74. http://dx.doi.org/10.2174/1874210601610010568.
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Objectives: Taper is a factor that determines final root canal dimensions and consequently, the space available for the cleaning action of irrigants. Therefore, the aim of this study was to investigate the influence of taper on intracanal bacterial reduction. Methods: Sterilized root canals of 25 mandibular incisors were inoculated with E. faecalis and then divided into two experimental groups and one control group (A= saline, B= NaOCl + EDTA and C= control, not prepared). Groups A and B were prepared to an apical size of #30/0.04, a culture was obtained and then prepared to #30/0.08 and cultured again. Final irrigation sequence was 30 ml of saline for group A and 10 ml of 17% EDTA followed by 10 ml of 2.5% NaOCl and 10 ml of saline for group B. The CFU ml-1 of the pre- and two post-operative samplings were recorded. Values were compared by performing ANOVA and FDR for multiple hypothesis testing. Results: No statistically significant difference between initial CFU ml-1 readings was recorded, whereas significant differences between group A and B at both 4% and 8% tapers were noted. Furthermore, a linear-dependent reduction of CFU ml-1 was recorded in each group from non-instrumented root canals to #30/0.04 and subsequently to #30/0.08. The positive control group shows the expected reduction of bacterial count. Conclusion: Chemomechanical instrumentation was more efficient at reducing E. faecalis when the taper of root canals increased from 4% to 8% and NaOCl plus EDTA led to a greater intracanal bacterial reduction than saline, regardless of the taper achieved.
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Gekas, Christos, Katrin E. Rhodes, Laurraine M. Gereige, Hildur Helgadottir, Roberto Ferrari, Siavash K. Kurdistani, Encarnación Montecino-Rodriguez, et al. "Mef2C is a lineage-restricted target of Scl/Tal1 and regulates megakaryopoiesis and B-cell homeostasis." Blood 113, no. 15 (April 9, 2009): 3461–71. http://dx.doi.org/10.1182/blood-2008-07-167577.
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Abstract The basic helix-loop-helix transcription factor stem cell leukemia gene (Scl) is a master regulator for hematopoiesis essential for hematopoietic specification and proper differentiation of the erythroid and megakaryocyte lineages. However, the critical downstream targets of Scl remain undefined. Here, we identified a novel Scl target gene, transcription factor myocyte enhancer factor 2 C (Mef2C) from Sclfl/fl fetal liver progenitor cell lines. Analysis of Mef2C−/− embryos showed that Mef2C, in contrast to Scl, is not essential for specification into primitive or definitive hematopoietic lineages. However, adult VavCre+Mef2Cfl/fl mice exhibited platelet defects similar to those observed in Scl-deficient mice. The platelet counts were reduced, whereas platelet size was increased and the platelet shape and granularity were altered. Furthermore, megakaryopoiesis was severely impaired in vitro. Chromatin immunoprecipitation microarray hybridization analysis revealed that Mef2C is directly regulated by Scl in megakaryocytic cells, but not in erythroid cells. In addition, an Scl-independent requirement for Mef2C in B-lymphoid homeostasis was observed in Mef2C-deficient mice, characterized as severe age-dependent reduction of specific B-cell progenitor populations reminiscent of premature aging. In summary, this work identifies Mef2C as an integral member of hematopoietic transcription factors with distinct upstream regulatory mechanisms and functional requirements in megakaryocyte and B-lymphoid lineages.
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Ren, Sheng Feng, Chang Qing Gao, and Ru Jian Ma. "Research on Grinding Characteristics of Ultrasonic Aided Grinding." Advanced Materials Research 197-198 (February 2011): 215–18. http://dx.doi.org/10.4028/www.scientific.net/amr.197-198.215.
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Experimental study of radial ultrasonic vibration aided grinding of sintered Nd-Fe-B permanent magnetic material was conducted contrasted with traditional grinding. The effect on normal grinding force of grinding parameters was analyzed respectively in the two grinding processes. Experimental results indicate that the discontinuous grinding mechanism caused by ultrasonic vibration is the main factor that reducing the normal grinding force. The process of radial ultrasonic vibration aided grinding is especially suitable for shape machining of sintered Nd-Fe-B permanent magnet.
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Zhuikova, Tatyana Valerievna, Anastasia Sergeevna Popova, and Eleonora Vasilievna Meling. "Morphological variability of Betula pendula Roth leaves under conditions of technogenic transformation of the environment." Samara Journal of Science 10, no. 1 (March 1, 2021): 65–73. http://dx.doi.org/10.17816/snv2021101109.
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The paper analyzes morphological characters variability of Betula pendula Roth leaves growing in the gradient of technogenic soil transformation. Biological material was collected in natural phytocoenoses and in the Pritagilskaya zone of the Middle Urals technogenically contaminated with heavy metals. In the gradient under study, a change in the shape of the leaf blade is observed: it is rounded, the base is straightened and the top is stretched. The sizes of leaf blades of Betula pendula are smaller under conditions of an average level of pollution than in the background and maximum polluted areas. The largest leaves are typical for B. pendula from the most polluted area. In the studied gradient of the technogenic transformation of the environment, four types of leaf blades forms were distinguished: 1) ovate with a rounded-wedge-shaped base and with a pointed apex; 2) triangular-broadly ovate with a rounded-wedge-shaped base and a pointed apex; 3) triangular-broadly ovate with a truncated base and a pointed apex; 4) triangular-broadly ovate with a truncated base and an elongated pointed apex. By the factor analysis the authors have identified the factors that explain 60% of the total variance of the leaf shape trait. The variables have large factor loads for the first factor (length and width of the leaf blade, length of the petiole, the distance from the tip of the leaf blade to the widest part) (42%) and smaller loads for the second one (leaf index) (18%). On the basis of these features, a discriminant analysis was carried out, the results of which indicate that the leaves of plants from the impact area differ from the rest. On the basis of the ratio of the general and consistent variability, morphological features were identified that are ecological indicators the distance between the bases of the first-second and second-third lateral veins of the first order, the distance from the widest part to the base of the leaf blade, IF (shape index sheet). The high overall and low consistent variability of these characteristics is determined to a greater extent by the influence of environmental factors. The analysis of changes patterns in the level of leaves morphological integration in the gradient of soils technogenic transformation showed that Betula pendula is characterized by a protective-stress developmental strategy.
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Travis, A., J. Hagman, L. Hwang, and R. Grosschedl. "Purification of early-B-cell factor and characterization of its DNA-binding specificity." Molecular and Cellular Biology 13, no. 6 (June 1993): 3392–400. http://dx.doi.org/10.1128/mcb.13.6.3392-3400.1993.
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Early-B-cell factor (EBF) is a nuclear protein that recognizes a functionally important sequence in the promoter of the mb-1 gene. Like the mb-1 gene, which encodes an immunoglobulin-associated protein, EBF is specifically expressed in the early stages of B-lymphocyte differentiation. We purified EBF by sequence-specific DNA affinity chromatography and examined its biochemical properties and DNA-binding specificity. Crude nuclear extract and affinity-purified EBF generated protein-DNA complexes with the mb-1 promoter that were indistinguishable in electrophoretic mobility shift and DNase I footprint assays. Fractionation of affinity-purified EBF by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and renaturation of isolated polypeptides indicated that EBF DNA-binding activity could be reconstituted from polypeptides with molecular masses of 62 to 65 kDa. Gel filtration chromatography suggested that native EBF has a molecular mass of 140 kDa, if a globular shape of the protein is assumed. Thus, EBF appears to be a dimer with subunits of 62 to 65 kDa. To characterize the DNA-binding specificity of purified EBF, we performed two sets of experiments. First, we examined various mutant EBF-binding sites for interaction with purified EBF in an electrophoretic mobility shift assay. Second, we used oligonucleotides containing pairs of randomized bases in a binding-site selection and amplification experiments to determine a preferred sequence for DNA binding by EBF. Taken together, the results of these experiments indicated that EBF recognizes variations on the palindromic sequence 5'-ATTCCCNNGGGAAT, with an optimal spacer of 2 bp between the half-sites.
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Travis, A., J. Hagman, L. Hwang, and R. Grosschedl. "Purification of early-B-cell factor and characterization of its DNA-binding specificity." Molecular and Cellular Biology 13, no. 6 (June 1993): 3392–400. http://dx.doi.org/10.1128/mcb.13.6.3392.
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Early-B-cell factor (EBF) is a nuclear protein that recognizes a functionally important sequence in the promoter of the mb-1 gene. Like the mb-1 gene, which encodes an immunoglobulin-associated protein, EBF is specifically expressed in the early stages of B-lymphocyte differentiation. We purified EBF by sequence-specific DNA affinity chromatography and examined its biochemical properties and DNA-binding specificity. Crude nuclear extract and affinity-purified EBF generated protein-DNA complexes with the mb-1 promoter that were indistinguishable in electrophoretic mobility shift and DNase I footprint assays. Fractionation of affinity-purified EBF by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and renaturation of isolated polypeptides indicated that EBF DNA-binding activity could be reconstituted from polypeptides with molecular masses of 62 to 65 kDa. Gel filtration chromatography suggested that native EBF has a molecular mass of 140 kDa, if a globular shape of the protein is assumed. Thus, EBF appears to be a dimer with subunits of 62 to 65 kDa. To characterize the DNA-binding specificity of purified EBF, we performed two sets of experiments. First, we examined various mutant EBF-binding sites for interaction with purified EBF in an electrophoretic mobility shift assay. Second, we used oligonucleotides containing pairs of randomized bases in a binding-site selection and amplification experiments to determine a preferred sequence for DNA binding by EBF. Taken together, the results of these experiments indicated that EBF recognizes variations on the palindromic sequence 5'-ATTCCCNNGGGAAT, with an optimal spacer of 2 bp between the half-sites.
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Ley, Klaus, Norbert Gerdes, and Holger Winkels. "ATVB Distinguished Scientist Award." Arteriosclerosis, Thrombosis, and Vascular Biology 37, no. 5 (May 2017): 764–77. http://dx.doi.org/10.1161/atvbaha.117.308611.
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Objective— Immune cells play a critical role in atherosclerosis. Costimulatory and coinhibitory molecules of the tumor necrosis factor receptor and CD28 immunoglobulin superfamilies not only shape T-cell and B-cell responses but also have a major effect on antigen-presenting cells and nonimmune cells. Approach and Results— Pharmacological inhibition or activation of costimulatory and coinhibitory molecules and genetic deletion demonstrated their involvement in atherosclerosis. This review highlights recent advances in understanding how costimulatory and coinhibitory pathways shape the immune response in atherosclerosis. Conclusions— Insights gained from costimulatory and coinhibitory molecule function in atherosclerosis may inform future therapeutic approaches.
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Belova, Irina V., and Graeme E. Murch. "Exploration of the Transition from Harrison Type-A Kinetics to Type-B Kinetics Regimes in Grain Boundary Diffusion." Defect and Diffusion Forum 273-276 (February 2008): 425–30. http://dx.doi.org/10.4028/www.scientific.net/ddf.273-276.425.
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We model the grain boundary tracer diffusion problem by constructing a 3D structure consisting of cubic grains each of equal volume. We build the structure in such a way that no four cubes have a common edge. It is shown that the transition point between Harrison Type-A and Type-B kinetics regimes occurs at a diffusant diffusion length roughly an order of magnitude smaller than for the extensively studied case of parallel grain boundary slabs. For two dimensional squares the transition point occurs at a diffusion length roughly a factor of five smaller than for parallel grain boundary slabs. Thus we can draw the conclusion that dimensionality and geometric shape are both important factors in the parametric analysis of the grain boundary diffusion problem.
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Feuerstein, Bernold, Nikolai Dotzek, and Jürgen Grieser. "Assessing a Tornado Climatology from Global Tornado Intensity Distributions." Journal of Climate 18, no. 4 (February 15, 2005): 585–96. http://dx.doi.org/10.1175/jcli-3285.1.
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Abstract Recent work demonstrated that the shape of tornado intensity distributions from various regions worldwide is well described by Weibull functions. This statistical modeling revealed a strong correlation between the fit parameters c for shape and b for scale regardless of the data source. In the present work it is shown that the quality of the Weibull fits is optimized if only tornado reports of F1 and higher intensity are used and that the c–b correlation does indeed reflect a universal feature of the observed tornado intensity distributions. For regions with likely supercell tornado dominance, this feature is the number ratio of F4 to F3 tornado reports R(F4/F3) = 0.238. The c–b diagram for the Weibull shape and scale parameters is used as a climatological chart, which allows different types of tornado climatology to be distinguished, presumably arising from supercell versus nonsupercell tornadogenesis. Assuming temporal invariance of the climatology and using a detection efficiency function for tornado observations, a stationary climatological probability distribution from large tornado records (U.S. decadal data 1950−99) is extracted. This can be used for risk assessment, comparative studies on tornado intensity distributions worldwide, and estimates of the degree of underreporting for areas with poor databases. For the 1990s U.S. data, a likely tornado underreporting of the weak events (F0, F1) by a factor of 2 can be diagnosed, as well as asymptotic climatological c,b values of c = 1.79 and b = 2.13, to which a convergence in the 1950–99 U.S. decadal data is verified.
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Huang, Cheng-Hung, and Chih-Yang Kuo. "A Nonlinear Inverse Design Problem for a Pipe Type Heat Exchanger Equipped with Internal Z-Shape Lateral Fins and Ribs." Energies 13, no. 23 (December 4, 2020): 6424. http://dx.doi.org/10.3390/en13236424.
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A non-linear three-dimensional inverse shape design problem was investigated for a pipe type heat exchanger to estimate the design variables of continuous lateral ribs on internal Z-shape lateral fins for maximum thermal performance factor η. The design variables were considered as the positions, heights, and number of ribs while the physical properties of air were considered as a polynomial function of temperature; this makes the problem non-linear. The direct problem was solved using software package CFD-ACE+, and the Levenberg–Marquardt method (LMM) was utilized as the optimization tool because it has been proven to be a powerful algorithm for solving inverse problems. Z-shape lateral fins were found to be the best thermal performance among Z-shape, S-shape, and V-shape lateral fins. The objective of this study was to include continuous lateral ribs to Z-shape lateral fins to further improve η. Firstly, the numerical solutions of direct problem were solved using both polynomial and constant air properties and then compared with the corrected solutions to verify the necessity for using polynomial air properties. Then, four design cases, A, B, C and D, based on various design variables were conducted numerically, and the resultant η values were computed and compared. The results revealed that considering continuous lateral ribs on the surface of Z-shape lateral fins can indeed improve η value at the design working condition Re = 5000. η values of designs A, B and C were approximately 13% higher than that for Z-shape lateral fins, however, when the rib numbers were increased, i.e., design D, the value of η became only 11.5 % higher. This implies that more ribs will not guarantee higher η value.
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Rosette, C., and M. Karin. "Cytoskeletal control of gene expression: depolymerization of microtubules activates NF-kappa B." Journal of Cell Biology 128, no. 6 (March 15, 1995): 1111–19. http://dx.doi.org/10.1083/jcb.128.6.1111.
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Cell shape changes exert specific effects on gene expression. It has been speculated that the cytoskeleton is responsible for converting changes in the cytoarchitecture to effects on gene transcription. However, the signal transduction pathways responsible for cytoskeletal-nuclear communication remained unknown. We now provide evidence that a variety of agents and conditions that depolymerize microtubules activate the sequence-specific transcription factor NF-kappa B and induce NF kappa B-dependent gene expression. These effects are caused by depolymerization of microtubule because they are blocked by the microtubule-stabilizing agent taxol. In nonstimulated cells, the majority of NF-kappa B resides in the cytosplasm as a complex with its inhibitor I kappa B. Upon cell stimulation, NF-kappa B translocates to the nucleus with concomitant degradation of I kappa B. We show that cold-induced depolymerization of microtubules also leads to I kappa B degradation and activation of NF-kappa B. However, the activated factor remains in the cytoplasm and translocates to the nucleus only upon warming to 37 degrees C, thus revealing two distinct steps in NF-kappa B activation. These findings establish a new role for NF-kappa B in sensing changes in the state of the cytoskeleton and converting them to changes in gene activity.
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Golubtsov, G. B., and R. S. Chalov. "COMPARATIVE HYDRO-MORPHOLOGICAL ANALYSIS OF THE ISLANDS OF DIFFERENTLY BRANCHED UPPER OB AND MIDDLE LENA RIVER CHANNELS." Bulletin of Udmurt University. Series Biology. Earth Sciences 30, no. 2 (July 30, 2020): 164–74. http://dx.doi.org/10.35634/2412-9518-2020-30-2-164-174.
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This article is devoted to the formation conditions and morphometric features of the river islands. Also it considers the rate of branching of the Upper Ob and Middle Lena river channels. They are the largest rivers, but the Middle Lena River is bigger than the Upper Ob River by 6.15 times of total runoff and 2.5 times of width. However, both of them have unstable or weakly stable channels, characterized by parallel-sleeve, alternating, one-sided and single branchings, formed by numerous islands. Their comparison makes it possible to establish the dependence of the conditions of islands formation, their parameters (length - L , width - B , shape - L / B ), types and number on the indicators of stability, total runoff, branching types and location in the channel (active or peripheral part). These correlations based on hydro-morphological analysis show that the shape of islands L / B and the branching rate of the channel - n / x depend on the degree of stability. It is a common feature of all branching types and stages of island evolution (elementary, small, large islands and island massifs). Uniform dependencies of island parameters on river bed stability for both rivers, despite their large-scale distortions, were obtained by taking into account the connection of channel width ( b ) with its runoff ( Q ) by introducing a correction factor of 2.5 for the river size. Also the formation conditions of elongated islands ( L / B > 5), were determined. Their shape does not correspond to the optimal ratio L / B = 3...4. The revealed patterns give an opportunity to clarify the previously proposed classification of the islands.
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Huang, Min, Xinyuan Gao, Jie Pan, Xiu Li, Caroline Hemingray, Kaida Xiao, and Manuel Melgosa. "Optimizing Color-Difference Formulas for 3D-Printed Objects." Sensors 22, no. 22 (November 16, 2022): 8869. http://dx.doi.org/10.3390/s22228869.
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Based on previous visual assessments of 440 color pairs of 3D-printed samples, we tested the performance of eight color-difference formulas (CIELAB, CIEDE2000, CAM02-LCD, CAM02-SCD, CAM02-UCS, CAM16-LCD, CAM16-SCD, and CAM16-UCS) using the standardized residual sum of squares (STRESS) index. For the whole set of 440 color pairs, the introduction of kL (lightness parametric factor), b (exponent in total color difference), and kL + b produced an average STRESS decrease of 2.6%, 26.9%, and 29.6%, respectively. In most cases, the CIELAB formula was significantly worse statistically than the remaining seven formulas, for which no statistically significant differences were found. Therefore, based on visual results using 3D-object colors with the specific shape, size, gloss, and magnitude of color differences considered here, we concluded that the CIEDE2000, CAM02-, and CAM16-based formulas were equivalent and thus cannot recommend only one of them. Disregarding CIELAB, the average STRESS decreases in the kL + b-optimized formulas from changes in each one of the four analyzed parametric factors were not statistically significant and had the following values: 6.2 units changing from color pairs with less to more than 5.0 CIELAB units; 2.9 units changing the shape of the samples (lowest STRESS values for cylinders); 0.7 units changing from nearly-matte to high-gloss samples; and 0.5 units changing from 4 cm to 2 cm samples.
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Dugina, V. B., A. Y. Alexandrova, K. Lane, E. Bulanova, and J. M. Vasiliev. "The role of the microtubular system in the cell response to HGF/SF." Journal of Cell Science 108, no. 4 (April 1, 1995): 1659–67. http://dx.doi.org/10.1242/jcs.108.4.1659.
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The effects of the microtubular drugs colcemid and taxol on the morphological changes induced by hepatocyte growth factor/scatter factor (HGF/SF) in MDCK cells were studied. Dynamic changes in the area and shape of individual cells were assessed by morphometric methods whereas alterations of the cytoskeleton were assessed by immunomorphological methods. The results suggest that there are two components in the response to HGF/SF: (a) activation of the extension of lamellae leading to cell spreading; and (b) reorganization of microtubules leading to polarization of cell shape. The latter response is highly sensitive to microtubular drugs, especially taxol. HGF/SF induced spreading in taxol-treated MDCK cells but these cells retained a non-polarized discoid shape and a pattern of actin microfilament bundles characteristic of the untreated cells. Colcemid and taxol did not prevent HGF/SF-induced migration of cells in Boyden chambers but completely inhibited the outgrowth of multicellular strands and tubules from cell aggregates in collagen gels. These results show that enhanced lamella formation in response to HGF/SF without polarization of cell shape is sufficient to induce cell motility. In contrast, microtubule-dependent polarization is essential for complex morphogenetic responses such as tubulogenesis in collagen gels.
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Yin, Xiangjie, Hang Lin, Yifan Chen, Yixian Wang, and Yanlin Zhao. "Precise evaluation method for the stability analysis of multi-scale slopes." SIMULATION 96, no. 10 (August 3, 2020): 841–48. http://dx.doi.org/10.1177/0037549720943274.
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Slope stability analysis is a multi-scale problem. Typically, owing to the distinctions of slope scales (e.g., slope height or slope angle) in practical engineering, the stability calculation results of slopes with various scales from numerical methods inevitably exhibit different computational precision levels in the case of identical computational grids, and therefore the stability results of different slopes cannot be compared. To achieve equal accuracy stability analysis for multi-scale slopes, this study establishes numerical models of slopes with various scales as well as different grid shapes and sizes to conduct stability analysis. The results show the following: (a) a positive correlation relationship exists between the safety factor of the slope and the scaling factor, which is defined as the ratio of the grid size to the slope height; (b) the definition of the refined safety factor is given, representing the safety factor that corresponds to the infinitesimal grid size and eliminating the computational error of slope stability analysis caused by grid size or shape; (c) on this basis, embarking on the composite influence of multiple scales of slope on stability analysis, the study proposes a simplified treatment method suitable for evaluating the refined safety factor of the multi-scale slopes, which is verified as valid and feasible by some examples.
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Sugahara, K., J. S. Rubin, R. J. Mason, E. L. Aronsen, and J. M. Shannon. "Keratinocyte growth factor increases mRNAs for SP-A and SP-B in adult rat alveolar type II cells in culture." American Journal of Physiology-Lung Cellular and Molecular Physiology 269, no. 3 (September 1, 1995): L344—L350. http://dx.doi.org/10.1152/ajplung.1995.269.3.l344.
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The production of pulmonary surfactant, a complex of phospholipids and lung-specific surfactant proteins, is a primary function of alveolar type II cells. Although previous studies have demonstrated a role for cell-extracellular matrix interactions and normal cell shape in the maintenance of differentiated function in primary cultures of adult rat type II cells, a positive role for growth factors in surfactant protein gene expression in isolated normal adult type II cells has not been reported. In the present study, we have examined the effects of a panel of hormones, growth factors, and cytokines on the expression of mRNAs for surfactant proteins A, B, and C (SP-A, SP-B, and SP-C). Our results show that keratinocyte growth factor (KGF) induced a two- to threefold increase in steady-state levels of mRNAs for SP-A and SP-B, but had no effect on or decreased SP-C mRNA. The increase in SP-A mRNA was accompanied by an increase in SP-A protein. The effects of KGF were both dose and time dependent, and they could be neutralized by a monoclonal antibody against KGF. The effects of KGF were mimicked by acidic fibroblast growth factor, which will bind the KGF receptor. We conclude that KGF can support differentiation of alveolar type II cells as well as act as a mitogen, thus suggesting an important role for KGF in maintenance of the alveolar epithelium.
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Psychountaki, Maria, Yannis Zervas, Konstantinos Karteroliotis, and Charles Spielberger. "Reliability and Validity of the Greek Version of the STAIC." European Journal of Psychological Assessment 19, no. 2 (April 2003): 124–30. http://dx.doi.org/10.1027//1015-5759.19.2.124.
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Summary: This study describes the adaptation of the State-Trait Anxiety Inventory for Children (STAIC; Spielberger, Edwards, Lushene, Montuori, & Platzek, 1973 ) to the Greek population. It was hypothesized that the STAIC would be able to measure children's state-trait anxiety levels. In the initial phase, a sample of 100 children, aged 9-12 years, was used in order to shape the final form of the inventory. In the final phase, two different samples (N = 875), aged 9-12 years, were used to test the validity and reliability of the inventory, using exploratory (Sample A; n = 425) and confirmatory (Sample B; n = 450) factor analyses. The results indicated that both scales possessed an acceptable internal consistency and reliability. The factor analysis in the total of the items indicated three factors, that is “absence of state anxiety,” “presence of state anxiety,” and “trait anxiety.” Also, confirmatory factor analysis (AMOS; Arbuckle, 1997 ) verified three factors. It is therefore concluded that the scales have a multifactorial structure and can be used among the Greek population to examine children's state and trait anxiety levels.
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Scharer, Christopher, Emily Blalock, Tian Mi, Benjamin Barwick, Scott Jenks, Bridget Neary, Dillon Patterson, et al. "Epigenetic programming underpins B cell dysfunction in human SLE." Journal of Immunology 202, no. 1_Supplement (May 1, 2019): 50.10. http://dx.doi.org/10.4049/jimmunol.202.supp.50.10.
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Abstract Systemic lupus erythematosus (SLE) is characterized by the expansion of extrafollicular pathogenic B cells derived from newly activated naïve cells. Although these cells have distinct markers and phenotypes, their epigenetic architecture and how it contributes to SLE remains poorly understood. To establish if epigenetic mechanisms contributed to pathogenic B cell programming in SLE, we systematically determined the DNA methylation, chromatin accessibility and transcriptome landscape of human B cell subsets from SLE and healthy subjects. To comprehensively cover the B cell lineage, we isolated resting naïve, activated subsets, class-switched memory, plasmabasts, and a newly defined effector B cell subset. These data define a differentiation hierarchy between the subsets and elucidate the epigenetic and transcriptional differences between effector and memory B cells. Intriguingly, an SLE epigenetic signature was already established in resting naïve cells and persisted in more differentiated subsets. DNA methylation profiling revealed a set of CpG surrounding IFN response genes whose methylation status were highly predictive of disease activity. The AP-1 and EGR transcription factor networks were highly enriched in the SLE accessible chromatin and dysregulated genes. Together, these transcription factors acted in synergy with TBET to shape the epigenome of expanded SLE effector B cell subsets. These results provide insights into the epigenetic programming of human B cell subsets, identify loci that correlate with the expansion of distinct pathogenic B cell subsets, and suggest that early alterations in the epigenome may predispose B cells towards a disease fate.
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Bayrón-Arcelay, Margarette, Kyara Rodríguez-Camacho, and Dimaris Acosta-Mercado. "Morphological Response of Bolivina Lowmani to Sediment Composition and Organic Matter: Applying Geometric Morphometrics for Potential Bio-Monitoring." Journal of Foraminiferal Research 50, no. 3 (July 1, 2020): 249–65. http://dx.doi.org/10.2113/gsjfr.50.3.249.
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ABSTRACT It is well established that sediment composition plays an important role in shaping the community of benthic foraminifera (e.g., species richness). To our knowledge, there is little information about morphometric variations in benthic foraminifera in relation to sediment composition and organic matter content. However, given their sensitivity to these environmental variables, variations in size (width and height of the test) and shape (form of the test) of the foraminifera could provide information about potential disturbances, serving as an index of anthropogenic pressure for coastal ecosystems. In this study, we used geometric morphometrics to compare the average size and shape of a common species, Bolivina lowmani, among islets in La Parguera, Puerto Rico. We hypothesized that the average size and shape of B. lowmani will be different among islets. We further hypothesize that there will be a concomitant morphometric gradient of B. lowmani with sediment particle size and organic matter content. After a random sampling approach, we found that size regressed as a function of mud content and shape variations regressed as a function of organic matter content. Therefore, sediment composition could be a factor affecting foraminiferal growth rates highlighting that the morphometrics of benthic foraminifera could be added to the list of potential indexes that could be used to track current environmental degradation in coastal habitats. Furthermore, our data validate the sensitivity of foraminifera and their usefulness as indicators of environmental hazards.
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Heldin, Carl-Henrik, and Bengt Westermark. "Mechanism of Action and In Vivo Role of Platelet-Derived Growth Factor." Physiological Reviews 79, no. 4 (January 10, 1999): 1283–316. http://dx.doi.org/10.1152/physrev.1999.79.4.1283.
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Platelet-derived growth factor (PDGF) is a major mitogen for connective tissue cells and certain other cell types. It is a dimeric molecule consisting of disulfide-bonded, structurally similar A- and B-polypeptide chains, which combine to homo- and heterodimers. The PDGF isoforms exert their cellular effects by binding to and activating two structurally related protein tyrosine kinase receptors, denoted the α-receptor and the β-receptor. Activation of PDGF receptors leads to stimulation of cell growth, but also to changes in cell shape and motility; PDGF induces reorganization of the actin filament system and stimulates chemotaxis, i.e., a directed cell movement toward a gradient of PDGF. In vivo, PDGF has important roles during the embryonic development as well as during wound healing. Moreover, overactivity of PDGF has been implicated in several pathological conditions. The sis oncogene of simian sarcoma virus (SSV) is related to the B-chain of PDGF, and SSV transformation involves autocrine stimulation by a PDGF-like molecule. Similarly, overproduction of PDGF may be involved in autocrine and paracrine growth stimulation of human tumors. Overactivity of PDGF has, in addition, been implicated in nonmalignant conditions characterized by an increased cell proliferation, such as atherosclerosis and fibrotic conditions. This review discusses structural and functional properties of PDGF and PDGF receptors, the mechanism whereby PDGF exerts its cellular effects, and the role of PDGF in normal and diseased tissues.
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Salauddin, Md, John O'Sullivan, Soroush Abolfathi, Shudhi Dong, and Jonathan Pearson. "DISTRIBUTION OF INDIVIDUAL WAVE OVERTOPPING VOLUMES ON A SLOPING STRUCTURE WITH A PERMEABLE FORESHORE." Coastal Engineering Proceedings, no. 36v (December 31, 2020): 54. http://dx.doi.org/10.9753/icce.v36v.papers.54.
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Maximum wave overtopping volumes on sea defences are an indicator for identifying risks to people and properties from wave hazards. The probability distribution of individual overtopping volumes can generally be described by a two-parameter Weibull distribution function (shape and scale parameters). Therefore, the reliable prediction of maximum individual wave overtopping volumes at coastal structures relies on an accurate estimation of the shape factor in the Weibull distribution. This study contributes to an improved understanding of the distribution of individual wave overtopping volumes at sloping structures by analysing the wave-by-wave overtopping volumes obtained from physical model experiments on a 1V:2H sloped impermeable structure with a permeable shingle foreshore of slope 1V:20H. Measurements of the permeable shingle foreshore were benchmarked against those from an identical experimental set-up with a smooth impermeable foreshore (1V:20H) of the same geometry. Results from both experimental set-ups were compared to commonly used empirical formulations, underpinned by the assumption that an impermeable foreshore exists in front of the sea structure. The effect on the shape factor in the Weibull distribution of incident wave steepness, relative crest freeboard, probability of overtopping waves and discharge are examined to determine the variation of individual overtopping volumes with respect to these key parameters. A key finding from the study is that no major differences in Weibull distribution shape parameter were observed for the tested impermeable and permeable sloped foreshores. Existing empirical formulae were also shown to predict reasonably well the Weibull distribution shape parameter, b, at sloping structures with both impermeable and permeable slopes.
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Jee, Soo-Chan, Yu Shin Lee, Joong Hee Lee, Sunghwan Park, Byungki Jin, and Myung Hwan Yun. "Anthropometric Classification of Human Hand Shapes in Korean Population." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 60, no. 1 (September 2016): 1200–1204. http://dx.doi.org/10.1177/1541931213601281.
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Hand tools designed without the anthropometric perspective lead to lower performance and safety. This study suggests a statistical hand shape classification with Korean anthropometric data. A total of 321 anthropometric data were used for this study. To investigate hand types, 27 anthropometric hand variables normalized by the stature of each participant and factor analysis and cluster analysis were conducted. As a result, three major factors were deduced: factors of hand breadth, palm length, and finger length. Additionally, four hand types were determined: (a) a spacious hand with short fingers, (b) a hand with short palm with above average fingers, (c) a long palm and fingers, and (d) a narrow hand and short fingers. In the male population, the spacious hand with short fingers type was dominant while the narrow hand and short fingers type was dominant in the female population. These results are expected to be preliminarily utilized in design for the Korean population.
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Park, Won Jo, Yong Bum Choi, Sun Chul Huh, and Han Ki Yoon. "Fatigue Crack Growth in Aluminum Borate Whisker Reinforced AC4CH Alloy Matrix Composite Fabricated by Squeeze Casing." International Journal of Modern Physics B 17, no. 08n09 (April 10, 2003): 1730–36. http://dx.doi.org/10.1142/s0217979203019587.
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Al 18 B 4 O 33 w / AC4CH composite was fabricated using squeeze-casting method in which the molten aluminum was infiltrated into the whisker preform mounted on the mould. The aluminum borate whisker is very effective in the improvement of the mechanical properties of the AC4CH alloy. This paper is focused on fatigue crack growth behavior of the composite under different stress ratios R = 0.1 and R = 0.05. The effects of stress ratio on fatigue crack growth behavior of Al 18 B 4 O 33 w / AC4CH have also been investigated. In addition, the fracture of the fatigue crack growth was also investigated using scanning electro microscopy (SEM). As the results of an investigation, the whisker reinforcement phases in the AC4CH alloy matrix are irregularly shaped and randomly dispersed. The fatigue crack growth behavior at equivalent stress intensity factor in Al 18 B 4 O 33 w / AC4CH was faster than that of AC4CH alloy and the curves are very steep compared to the traditional metallic alloy. The region of stable crack growth in AC4CH was shown that the characteristic of surface has rough shape. It was appeared a kind of dimple type on the surface. But in case of Al 18 B 4 O 33 w / AC4CH , the characteristic of surface was gross brittle failure.
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van Kuijk, K. S. R., M. Reijman, S. M. A. Bierma-Zeinstra, J. H. Waarsing, and D. E. Meuffels. "Posterior cruciate ligament injury is influenced by intercondylar shape and size of tibial eminence." Bone & Joint Journal 101-B, no. 9 (September 2019): 1058–62. http://dx.doi.org/10.1302/0301-620x.101b9.bjj-2018-1567.r1.
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Aims Little is known about the risk factors that predispose to a rupture of the posterior cruciate ligament (PCL). Identifying risk factors is the first step in trying to prevent a rupture of the PCL from occurring. The morphology of the knee in patients who rupture their PCL may differ from that of control patients. The purpose of this study was to identify any variations in bone morphology that are related to a PCL. Patients and Methods We compared the anteroposterior (AP), lateral, and Rosenberg view radiographs of 94 patients with a ruptured PCL to a control group of 168 patients matched by age, sex, and body mass index (BMI), but with an intact PCL after a knee injury. Statistical shape modelling software was used to assess the shape of the knee and determine any difference in anatomical landmarks. Results We found shape variants on the AP and Rosenberg view radiographs to be significantly different between patients who tore their PCL and those with an intact PCL after a knee injury. Overall, patients who ruptured their PCL have smaller intercondylar notches and smaller tibial eminences than control patients. Conclusion This study shows that differences in the shape of the knee are associated with the presence of a PCL rupture after injury. A smaller and more sharply angled intercondylar notch and a more flattened tibial eminence are related to PCL rupture. This suggests that the morphology of the knee is a risk factor for sustaining a PCL rupture. Cite this article: Bone Joint J 2019;101-B:1058–1062.
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Kreisberg, J. I., M. A. Venkatachalam, R. A. Radnik, and P. Y. Patel. "Role of myosin light-chain phosphorylation and microtubules in stress fiber morphology in cultured mesangial cells." American Journal of Physiology-Renal Physiology 249, no. 2 (August 1, 1985): F227—F235. http://dx.doi.org/10.1152/ajprenal.1985.249.2.f227.
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Induced elevations in intracellular cAMP caused remarkable shape changes in cultured mesangial cells that were prevented by prostaglandin E2 (PGE2). The purpose of this study was to determine the morphological and physiological basis for these alterations. Coincident with elevated levels of cAMP and shape change there was rapid dissolution of stress fibers. Cytochalasin B treatment also caused shape change and stress fiber dissolution. Stress fibers were visualized by fluorescence microscopy after appropriate staining. In such cells, microtubules were intact. PGE2 prevented stress fiber loss as well as shape change if it was included in the medium from the outset, or restored stress fibers and normal morphology within 30 min if it was added following shape change. Agents that depolymerize microtubules also prevented both stress fiber loss and shape change. Coincident with stress fiber loss and shape change induced by elevations of cAMP, there was a decrease in the rate of [32P]-orthophosphate incorporation into myosin light chain; this was also prevented or reversed by PGE2. Remarkably, PGE2 alone caused an increase in the rate of [32P]orthophosphate incorporation into myosin light chain in cells that were otherwise untreated. Phosphorylation of the light chain of myosin may be an important factor in the maintenance of stress fiber morphology. The results of this study point out complex interrelationships between microtubules, and stress fibers in the maintenance of cell shape needing further study. The model systems that are presented seem suited for such investigation.
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Jusmaldi, Jusmaldi, Ardana Reswari Dianingrum, and Nova Hariani. "The growth pattern and condition factors of three spot gourami Trichopodus trichopterus (Pallas, 1770) from the Lempake Dam, East Kalimantan." Jurnal Iktiologi Indonesia 21, no. 3 (October 1, 2021): 215–33. http://dx.doi.org/10.32491/jii.v21i3.588.
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The growth pattern and condition factors of three spots gourami Trichopodus trichopterus (Pallas, 1770) from Lempake Dam, East Kalimantan, are not yet informed. These studies aimed to investigate fishes' length and body weight, sex ratio, length-bodyweight relationships, growth patterns, and condition factors. The collection of fish sampling was carried out monthly from February to May 2020. A total of 912 individual samples of sepat rawa fish were caught by 15 fish traps using a purposive sampling method at three stations. This research showed that the total length of the fishes analyzed ranged from 31.68 to 103.53 mm, while body weight ranged from 1.12 to 7.22 g. The sex ratio in males and females was 1:1.19. The regression model of the length-body weight relationships calculated was W=3x10-5L2.861 for total samples, W=5x10-5L2.710 for males, and W=2x10-5L2.977 for females. The length-body weight was obtained strong relationships in all samples and sexes, with the regression coefficient (r) ranging from 0.965 to 0.977. An isometric growth pattern and the growth coefficient “b”=2.977 was observed in females, while a negative allometric growth pattern in males and both sexes, with the growth coefficient “b”= 2.710 and “b”=2.861. The values of relative condition factor (Kn) observed for females were ranged from 1.472 to 1.555 and for males ranged from 1.024 to 1.082. The growth pattern and relative condition factor of three spot gourami in the Lempake Dam were affected by the number of fishes in gonad mature condition and body shape.
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Žnidarič, Aleš, and Jan Kalin. "Using bridge weigh-in-motion systems to monitor single-span bridge influence lines." Journal of Civil Structural Health Monitoring 10, no. 5 (July 31, 2020): 743–56. http://dx.doi.org/10.1007/s13349-020-00407-2.
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Abstract Bridge weigh-in-motion systems use instrumented bridges or culverts to weigh vehicles as they pass over the structures. They also provide data to allow the calculation of several bridge performance indicators. The article starts with the basics of a bridge weigh-in-motion system and briefly describes two key bridge performance indicators, girder distribution factor and dynamic amplification factor, which are also derived from B-WIM measurements. The central part of the article focuses on monitoring of influence lines, the third key parameter that characterises the bridge performance under traffic loads. First, the method of calculating the bending moment influence lines from random heavy traffic is described. A coefficient of rotational stiffness is introduced, which defines the shape of influence lines around the supports as a linear combination of the ideal simply supported and fixed supported influence lines, to allow quantifying the influence line changes. Then the long-term monitoring of influence lines is investigated on four different single-span test bridges. The initial focus is given on the examination of the effect of temperature on the shape of influence lines. Finally, two sets of influence lines are compared on one test bridge, one from before and the other from after replacing the expansion joints and bearings. The work done so far confirms that calculating of influence lines from random vehicles with a B-WIM system is entirely feasible and that differences in their shape can be detected on single-span bridges. What remains to be investigated is the comparison of these differences to the actual damages and under which circumstances the proposed procedure can compete with or better the routine bridge inspection and the conventional monitoring techniques.
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Qin, Lang, Shiwen Ding, Zhilei Wang, Runzhou Jiang, and Zhen He. "Host Plants Shape the Codon Usage Pattern of Turnip Mosaic Virus." Viruses 14, no. 10 (October 15, 2022): 2267. http://dx.doi.org/10.3390/v14102267.
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Turnip mosaic virus (TuMV), an important pathogen that causes mosaic diseases in vegetable crops worldwide, belongs to the genus Potyvirus of the family Potyviridae. Previously, the areas of genetic variation, population structure, timescale, and migration of TuMV have been well studied. However, the codon usage pattern and host adaptation analysis of TuMV is unclear. Here, compositional bias and codon usage of TuMV were performed using 184 non-recombinant sequences. We found a relatively stable change existed in genomic composition and a slightly lower codon usage choice displayed in TuMV protein-coding sequences. Statistical analysis presented that the codon usage patterns of TuMV protein-coding sequences were mainly affected by natural selection and mutation pressure, and natural selection was the key influencing factor. The codon adaptation index (CAI) and relative codon deoptimization index (RCDI) revealed that TuMV genes were strongly adapted to Brassica oleracea from the present data. Similarity index (SiD) analysis also indicated that B. oleracea is potentially the preferred host of TuMV. Our study provides the first insights for assessing the codon usage bias of TuMV based on complete genomes and will provide better advice for future research on TuMV origins and evolution patterns.
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Setti, G. "Quasars: Their Evolution, Absorption Lines and the Intergalactic Gas." Transactions of the International Astronomical Union 20, no. 1 (1988): 666–70. http://dx.doi.org/10.1017/s0251107x00007537.
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For many years now it has been known that the number vs. magnitude counts of quasars is the prima facie evidence of a cosmological evolution of this class of objects. Down to an apparent magnitude B - 19 the number of quasars increases by almost a factor 8 per magnitude Interval, compared to a factor 4 obtained in an Euclidean universe filled with a uniform distribution of sources, and correspondingly less for the classical Friedmann models of Gen. Relativity due to the red-shift effects. This strong evolution has been recently questioned because of several biases which may artificially steepen the slope of the counts in the optical surveys. Deep surveys of quasars selected via multi-colour techniques down to B - 23 have confirmed the long standing inference that the number count relationship must flatten beyond B - 20. As a consequence, pure density evolution models, where only the number density of quasars increases with the redshift z, leaving unchanged the shape of the local luminosity function, are ruled out, since too many quasars are predicted at faint magnitudes compared to the dramatic flattening of the counts (see, e.g., ref. 4).
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Nguatem, W., M. Drauschke, and H. Mayer. "Localization of Windows and Doors in 3d Point Clouds of Facades." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences II-3 (August 7, 2014): 87–94. http://dx.doi.org/10.5194/isprsannals-ii-3-87-2014.
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In this paper, we present a fully automatic approach to localize the outlines of facade objects (windows and doors) in 3D point clouds of facades. We introduce an approach to search for the main facade wall and locate the facade objects within a probabilistic framework. Our search routine is based on Monte Carlo Simulation (MC-Simulation). Templates containing control points of curves are used to approximate the possible shapes of windows and doors. These are interpolated using parametric B-spline curves. These templates are scored in a sliding window style over the entire facade using a likelihood function in a probabilistic matching procedure. This produces many competing results for which a two layered model selection based on Bayes factor is applied. A major thrust in our work is the introduction of a 2D shape-space of similar shapes under affine transform in this architectural scene. This transforms the initial parametric B-splines curves representing the outlines of objects to curves of affine similarity in a strongly reduced dimensionality thus facilitating the generation of competing hypotheses within the search space. A further computational speedup is achieved through the clustering of the search space to disjoint regions, thus enabling a parallel implementation. We obtain state-of-the results on self-acquired data sets. The robustness of our algorithm is evaluated on 3D point clouds from image matching and LiDAR data of diverse quality.
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Bogaard, JM, SE Overbeek, AF Verbraak, C. Vons, HT Folgering, TW van der Mark, CM Roos, and PJ Sterk. "Pressure-volume analysis of the lung with an exponential and linear-exponential model in asthma and COPD. Dutch CNSLD Study Group." European Respiratory Journal 8, no. 9 (September 1, 1995): 1525–31. http://dx.doi.org/10.1183/09031936.95.08091525.
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The prevalence of abnormalities in lung elasticity in patients with asthma or chronic obstructive pulmonary disease (COPD) is still unclear. This might be due to uncertainties concerning the method of analysis of quasistatic deflation lung pressure-volume curves. Pressure-volume curves were obtained in 99 patients with moderately severe asthma or COPD. These patients were a subgroup from a Dutch multicentre trial; the entire group was selected on the basis of a moderately lowered % predicted forced expiratory volume in one second (FEV1), and a provocative concentration of histamine producing a 20% decrease in FEV1 (PC20) < 8 mg.mL-1 obtained with the 2 min tidal breathing technique. The curves were fitted with an exponential (E) model and an exponential model which took the linear appearance in the mid vital capacity range into account (linear-exponential (LE)). The linear-exponential model showed a markedly better fit ability, yielding additional parameters, such as the compliance at functional residual capacity (FRC) level as slope of the linear part (b), and the volume at which the linear part changed into the exponential part of the curve (transition volume (Vtr)). Vtr (mean value Vtr/total lung capacity (TLC) = 0.79 (SD 0.07)) showed a close positive linear correlation with obstruction and hyperinflation variables, which might be due to airway closure, already starting at elevated lung volumes. The exponential shape factor K was closely correlated with b and mean values (K = 1.32 (SD 0.05) kPa-1; b = 2.96 (SD 1.16) L,kPa-1) and the relationship with age was comparable with data reported in healthy individuals. The shape factor of the linear-exponential fit showed no correlation with any elasticity related variable. Neither the elastic recoil at 90% TLC, as obtained from the linear-exponential fit, nor its relationship with age were significantly different from healthy individuals. We conclude that, for a more accurate description of the lung pressure-volume curve, a linear-exponential fit is preferable to an exponential model. However, the physiological relevance of the shape parameter (KLE) is still unclear. These results indicate that patients with moderately severe asthma or COPD had, on average, no appreciable loss of elastic lung recoil as compared with healthy individuals.
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Vaudo, Anthony D., Harland M. Patch, David A. Mortensen, John F. Tooker, and Christina M. Grozinger. "Macronutrient ratios in pollen shape bumble bee (Bombus impatiens) foraging strategies and floral preferences." Proceedings of the National Academy of Sciences 113, no. 28 (June 28, 2016): E4035—E4042. http://dx.doi.org/10.1073/pnas.1606101113.
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To fuel their activities and rear their offspring, foraging bees must obtain a sufficient quality and quantity of nutritional resources from a diverse plant community. Pollen is the primary source of proteins and lipids for bees, and the concentrations of these nutrients in pollen can vary widely among host-plant species. Therefore we hypothesized that foraging decisions of bumble bees are driven by both the protein and lipid content of pollen. By successively reducing environmental and floral cues, we analyzed pollen-foraging preferences of Bombus impatiens in (i) host-plant species, (ii) pollen isolated from these host-plant species, and (iii) nutritionally modified single-source pollen diets encompassing a range of protein and lipid concentrations. In our semifield experiments, B. impatiens foragers exponentially increased their foraging rates of pollen from plant species with high protein:lipid (P:L) ratios; the most preferred plant species had the highest ratio (∼4.6:1). These preferences were confirmed in cage studies where, in pairwise comparisons in the absence of other floral cues, B. impatiens workers still preferred pollen with higher P:L ratios. Finally, when presented with nutritionally modified pollen, workers were most attracted to pollen with P:L ratios of 5:1 and 10:1, but increasing the protein or lipid concentration (while leaving ratios intact) reduced attraction. Thus, macronutritional ratios appear to be a primary factor driving bee pollen-foraging behavior and may explain observed patterns of host-plant visitation across the landscape. The nutritional quality of pollen resources should be taken into consideration when designing conservation habitats supporting bee populations.
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Kadyan, Sunil, Narinder Bhasin, and Vikas Madhukar. "Impact of claim settlement procedure of health insurance companies on customer satisfaction during the pandemic: A case of third-party administrators." Insurance Markets and Companies 13, no. 1 (November 14, 2022): 66–80. http://dx.doi.org/10.21511/ins.13(1).2022.06.
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The claim settlement process is one of the most critical aspects of health insurance. Many policyholder grievances often surface during claim settlement, which will likely shape the insurer’s reputation. Hence, this study aims to evaluate the relationships between hypothesized factors concerning the third-party administrator’s claim settlement process as perceived by policyholders. The paper used the data of policyholders from Delhi/NCR, India, who have availed the cashless claims in the last three years. In the process, a total of 790 questionnaires were sought to be. The methodology used was the extractive factor analysis comprising the KMO test, reliability assessment with Cronbach’s Alpha, and correlation assessment. The study attempted to evaluate all the contributing factors that shape the third-party administrator’s behavior during the claim settlement. Therefore, different factors were identified (themes A, B, C, and D). The study reported a significant relationship between insurance company perceptions (0.162), network hospital perceptions (0.182), product design (0.180), insurance agent (0.332), communications (0.114), disclosure (0.122), internal practices (0.143), and TPA claim settlement prospects across the Indian perspective. The contextual impacts on individual and group decision-making must be monitored and accommodated across effective public policy management concerning settlement of health insurance claims. The study findings could help insurers create business models leading to better customer satisfaction and congruence between agents, policyholders, TPAs, and health insurance companies.