DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, C. J.; Chathoth, S. M., E-mail: smavilac@cityu.edu.hk; Podlesnyak, A.
2015-09-28
Extensive efforts have been made to develop metallic-glasses with large casting diameter. Such efforts were hindered by the poor understanding of glass formation mechanisms and the origin of the glass-forming ability (GFA) in metallic glass-forming systems. In this work, we have investigated relaxation dynamics of a model bulk glass-forming alloy system that shows the enhanced at first and then diminished GFA on increasing the percentage of micro-alloying. The micro-alloying did not have any significant impact on the thermodynamic properties. The GFA increasing on micro-alloying in this system cannot be explained by the present theoretical knowledge. Our results indicate that atomicmore » caging is the primary factor that influences the GFA. The composition dependence of the atomic caging time or residence time is found to be well correlated with GFA of the system.« less
Chen, C. J.; Podlesnyak, A.; Mamontov, E.; ...
2015-09-28
We've made extensive efforts to develop metallic-glasses with large casting diameter. Such efforts were hindered by the poor understanding of glass formation mechanisms and the origin of the glass-forming ability (GFA) in metallic glass-forming systems. We have investigated relaxation dynamics of a model bulk glass-forming alloy system that shows the enhanced at first and then diminished GFA on increasing the percentage of micro-alloying. The micro-alloying did not have any significant impact on the thermodynamic properties. The GFA increasing on micro-alloying in this system cannot be explained by the present theoretical knowledge. Finally, our results indicate that atomic caging is themore » primary factor that influences the GFA. The composition dependence of the atomic caging time or residence time is found to be well correlated with GFA of the system.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sun, Y. T.; Cao, C. R.; Huang, K. Q.
2014-08-04
The glass-forming ability (GFA) of an alloy, closely related to its ability to resist crystallization, is a crucial issue in condensed matter physics. So far, the studies on GFA are mostly statistical and empirical guides. Benefiting from the ultrahigh thermal stability of ultrathin metallic glassy film and high resolution spherical aberration-corrected transmission electron microscope, the crystallization of atomically thin ZrCu and its microalloyed ZrCuAl glasses with markedly different GFA was investigated at the atomic scale. We find the Zr diffusivity estimated from the density of nuclei is dramatically decreased by adding of Al, which is the major reason for themore » much better GFA of the ZrCuAl metallic glass.« less
NASA Astrophysics Data System (ADS)
Xu, Xiao-Jin; Long, Zhi-Lin; Liu, Wei; Liao, Guang-Kai
2017-11-01
In this paper, based on the reduced glass transition temperature ({{T}rg} ) proposed by Turnbull and the relation between the glass-forming ability (GFA) and the short-range bond ordering of liquids demonstrated by Tanaka, a detailed analysis on the specific roles of {{T}rg} and fragility of the glass forming liquid (m) in characterizing the GFA has been conducted, and then a novel GFA parameter α [=2/3× (100{{T}rg}{)}-(16/100)× m=67{{T}rg}-0.16m] was put forward. This new GFA parameter α , which increases with a decrease in the critical cooling rate (R c) for glass formation, is a complex function of {{T}rg} and m. The relationship between R c and the parameter α was identified and verified using available literature data for broad range of amorphous alloys with widely varying GFA. The correlation coefficient (R 2) of 0.9 clearly shows an excellent correlation between GFA and the parameter α and that α is a more superior indicator compared to currently reported similar GFA parameters.
An important factor powerfully influencing the Al Ni-based alloys' glass-forming ability
NASA Astrophysics Data System (ADS)
Bo, Zhang; Xiufang, Bian; Chunxia, Fu; Na, Han; Jiankun, Zhou; Weimin, Wang
2005-12-01
In order to get better glass-forming abilities (GFAs), Ni atoms are partially replaced by Cu and Co atoms in Al84Ni12Zr4 alloys. Thermal analysis shows that the reduced crystallization temperature Trx has no direct correlation with the GFA of the alloys. However, it is notable that prepeaks have been found in the total structure factors of the amorphous Al84Ni(12-x)Zr4Cux and Al84Ni(12-x)Zr4Cox alloys. In addition, the results prove that the intensity of the prepeaks influences the GFA powerfully. The amorphous alloys with larger intensity of the prepeak show better GFA. The influence of prepeaks on the GFA can be explained by the atomic configuration difference among the liquid, crystal and glass states.
Electronic structure and glass forming ability in early and late transition metal alloys
NASA Astrophysics Data System (ADS)
Babić, E.; Ristić, R.; Figueroa, I. A.; Pajić, D.; Skoko, Ž.; Zadro, K.
2018-03-01
A correlation between the change in magnetic susceptibility (Δχexp) upon crystallisation of Cu-Zr and Hf metallic glasses (MG) with their glass forming ability (GFA) observed recently, is found to apply to Cu-Ti and Zr-Ni alloys, too. In particular, small Δχexp, which reflects similar electronic structures, ES, of glassy and corresponding crystalline alloys, corresponds to high GFA. Here, we studied Δχexp for five Cu-Ti and four Cu-Zr and Ni-Zr MGs. The fully crystalline final state of all alloys was verified from X-ray diffraction patterns. The variation of GFA with composition in Cu-Ti, Cu-Zr and Cu-Hf MGs was established from the variation of the corresponding critical casting thickness, dc. Due to the absence of data for dc in Ni-Zr MGs their GFA was described using empirical criteria, such as the reduced glass transition temperature. A very good correlation between Δχexp and dc (and/or other criteria for GFA) was observed for all alloys studied. The correlation between the ES and GFA showed up best for Cu-Zr and NiZr2 alloys where direct data for the change in ES (ΔES) upon crystallisation are available. The applicability of the Δχexp (ΔES) criterion for high GFA (which provides a simple way to select the compositions with high GFA) to other metal-metal MGs (including ternary and multicomponent bulk MGs) is briefly discussed.
Improvement of glass-forming ability and phase separation in Cu Ti-rich
DOE Office of Scientific and Technical Information (OSTI.GOV)
Park, E S; Chang, H J; Kim, D H
2010-01-01
Present study reports improvement of glass-forming ability (GFA) and phase separation in Cu Ti-rich Cu Ti Zr Ni Si bulk metallic glasses (BMGs) by tailoring the constituent elements. The MA of metalloid element, Sn having relatively large negative enthalpy of mixing can lead to improve GFA (up to 8mm in diameter) as well as thermal stability (up toTx = 48K) by optimizing the substitution element. And the addition of elements having relatively large positive enthalpy of mixing (partial substitution of Zr or Ti with Y) can lead to the liquid state phase separation in Cu Ti Sn Zr Ni Simore » BMG, although the addition lead to drastic deterioration of the GFA.« less
A slow atomic diffusion process in high-entropy glass-forming metallic melts
NASA Astrophysics Data System (ADS)
Chen, Changjiu; Wong, Kaikin; Krishnan, Rithin P.; Embs, Jan P.; Chathoth, Suresh M.
2018-04-01
Quasi-elastic neutron scattering has been used to study atomic relaxation processes in high-entropy glass-forming metallic melts with different glass-forming ability (GFA). The momentum transfer dependence of mean relaxation time shows a highly collective atomic transport process in the alloy melts with the highest and lowest GFA. However, a jump diffusion process is the long-range atomic transport process in the intermediate GFA alloy melt. Nevertheless, atomic mobility close to the melting temperature of these alloy melts is quite similar, and the temperature dependence of the diffusion coefficient exhibits a non-Arrhenius behavior. The atomic mobility in these high-entropy melts is much slower than that of the best glass-forming melts at their respective melting temperatures.
Correlation between the Arrhenius crossover and the glass forming ability in metallic glasses.
Wen, Tongqi; Yao, Wenjing; Wang, Nan
2017-10-13
The distinctive characteristic of the metallic glass-forming system is that the variation in viscosity with temperature obeys Vogel-Fulcher-Tammann (VFT) relationship in the undercooled state and Arrhenius relationship in the high temperature region. A dimensionless index has thus been proposed based on the Arrhenius-VFT crossover and the classical nucleation rate and growth rate theory to evaluate the glass-forming ability (GFA). The indicator G(a) is expressed with the combination of T g , the glass transition temperature, T x , the onset crystallization temperature, T l , the liquidus temperature, T 0 , the VFT temperature, and a a constant that could be determined according to the best correlation between G(a) and the critical cooling rate (R c ). Compared with other GFA indexes, G(a) shows the best fit with R c , with the square of the correlation coefficient (R 2 ) being 0.9238 when a = 0.15 for the 23 various alloy systems concerned about. Our results indicate the crossover in the viscosity variation has key effect on GFA and one can use the index G(a) to predict R c and GFA for different alloys effectively.
Structure-induced microalloying effect in multicomponent alloys
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guo, Gu -Qing; Yang, Liang; Wu, Shi -Yang
2016-04-28
In this study, the microalloying effect on glass-forming ability (GFA) has been investigated from the structural aspect, by performing synchrotron radiation x-ray diffraction and absorption measurements coupled with simulations in the NiNbZr ternary system. We propose a new parameter which counts the fraction of the fivefold symmetries in all clusters and find it is strongly associated with the GFA. In particular, this structural parameter has the highest value in a composition where the best GFA is achieved. The present work provides an in-depth understanding of microalloying-induced high GFAs in multicomponent alloys.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Kai; Fan, Meng; Liu, Yanhui
When a liquid is cooled well below its melting temperature at a rate that exceeds the critical cooling rate R{sub c}, the crystalline state is bypassed and a metastable, amorphous glassy state forms instead. R{sub c} (or the corresponding critical casting thickness d{sub c}) characterizes the glass-forming ability (GFA) of each material. While silica is an excellent glass-former with small R{sub c} < 10{sup −2} K/s, pure metals and most alloys are typically poor glass-formers with large R{sub c} > 10{sup 10} K/s. Only in the past thirty years have bulk metallic glasses (BMGs) been identified with R{sub c} approachingmore » that for silica. Recent simulations have shown that simple, hard-sphere models are able to identify the atomic size ratio and number fraction regime where BMGs exist with critical cooling rates more than 13 orders of magnitude smaller than those for pure metals. However, there are a number of other features of interatomic potentials beyond hard-core interactions. How do these other features affect the glass-forming ability of BMGs? In this manuscript, we perform molecular dynamics simulations to determine how variations in the softness and non-additivity of the repulsive core and form of the interatomic pair potential at intermediate distances affect the GFA of binary alloys. These variations in the interatomic pair potential allow us to introduce geometric frustration and change the crystal phases that compete with glass formation. We also investigate the effect of tuning the strength of the many-body interactions from zero to the full embedded atom model on the GFA for pure metals. We then employ the full embedded atom model for binary BMGs and show that hard-core interactions play the dominant role in setting the GFA of alloys, while other features of the interatomic potential only change the GFA by one to two orders of magnitude. Despite their perturbative effect, understanding the detailed form of the intermetallic potential is important for designing BMGs with cm or greater casting thickness.« less
Interfacial free energy controlling glass-forming ability of Cu-Zr alloys.
Kang, Dong-Hee; Zhang, Hao; Yoo, Hanbyeol; Lee, Hyun Hwi; Lee, Sooheyong; Lee, Geun Woo; Lou, Hongbo; Wang, Xiaodong; Cao, Qingping; Zhang, Dongxian; Jiang, Jianzhong
2014-06-04
Glass is a freezing phase of a deeply supercooled liquid. Despite its simple definition, the origin of glass forming ability (GFA) is still ambiguous, even for binary Cu-Zr alloys. Here, we directly study the stability of the supercooled Cu-Zr liquids where we find that Cu64Zr36 at a supercooled temperature shows deeper undercoolability and longer persistence than other neighbouring compositions with an equivalent driving Gibbs free energy. This observation implies that the GFA of the Cu-Zr alloys is significantly affected by crystal-liquid interfacial free energy. In particular, the crystal-liquid interfacial free energy of Cu64Zr36 in our measurement was higher than that of other neighbouring liquids and, coincidently a molecular dynamics simulation reveals a larger glass-glass interfacial energy value at this composition, which reflects more distinct configuration difference between liquid and crystal phase. The present results demonstrate that the higher crystal-liquid interfacial free energy is a prerequisite of good GFA of the Cu-Zr alloys.
U-based metallic glasses with superior glass forming ability
NASA Astrophysics Data System (ADS)
Xu, Hongyang; Ke, Haibo; Huang, Huogen; Zhang, Pengguo; Pu, Zhen; Zhang, Pei; Liu, Tianwei
2018-02-01
By using Al as the third and B as the fourth but minor alloying elements for the U66.7Co33.3 basic metallic glass, a series of U-Co-Al(-B) alloys were designed. The quaternary U-Co-Al-B alloys exhibit significantly improved glass-forming ability (GFA) than previously reported U-based metallic glasses. Low fragility (∼24) is found for these new U-based metallic glasses. The improvement in GFA would result from denser atomic packing in the undercooled liquids due to the presence of small B atoms. Some U-Co-Al(-B) glasses showed corrosion resistance comparable to that of U64Co34Al2 glass, known for premium anti-corrosive performance among the unveiled U-based glasses.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sedighi, Sina; Kirk, Donald Walter; Singh, Chandra Veer, E-mail: chandraveer.singh@utoronto.ca
2015-09-21
Bulk metallic glasses are a relatively new class of amorphous metal alloy which possess unique mechanical and magnetic properties. The specific concentrations and combinations of alloy elements needed to prevent crystallization during melt quenching remains poorly understood. A correlation between atomic properties that can explain some of the previously identified glass forming ability (GFA) anomalies of the NiAl and CuZr systems has been identified, with these findings likely extensible to other transition metal–transition metal and transition metal–metalloid (TM–M) alloy classes as a whole. In this work, molecular dynamics simulation methods are utilized to study thermodynamic, kinetic, and structural properties ofmore » equiatomic CuZr and NiAl metallic glasses in an attempt to further understand the underlying connections between glass forming ability, nature of atomic level bonding, short and medium range ordering, and the evolution of structure and relaxation properties in the disordered phase. The anomalous breakdown of the fragility parameter as a useful GFA indicator in TM–M alloy systems is addressed through an in-depth investigation of bulk stiffness properties and the evolution of (pseudo)Gruneisen parameters over the quench domain, with the efficacy of other common glass forming ability indicators similarly being analyzed through direct computation in respective CuZr and NiAl systems. Comparison of fractional liquid-crystal density differences in the two systems revealed 2-3 times higher values for the NiAl system, providing further support for its efficacy as a general purpose GFA indicator.« less
Atomic structure and glass forming ability of Cu46Zr46Al8 bulk metallic glass
NASA Astrophysics Data System (ADS)
Wang, X. D.; Jiang, Q. K.; Cao, Q. P.; Bednarcik, J.; Franz, H.; Jiang, J. Z.
2008-11-01
By using a combination of state-of-the-art experimental and computational methods, the high glass forming ability (GFA) of Cu46Zr46Al8 alloy is studied from the view of its atomic packing. Three-dimensional atomic configuration is well established. It is found that Al atoms almost homogeneously distribute around Cu and Zr atoms without segregation, causing the local environment around Cu and Zr atoms in Cu46Zr46Al8 bulk metallic glass different from that of the major competing phase of Cu10Zr7. Furthermore, the addition of Al not only increases the amount of icosahedronlike clusters but also makes them more homogeneous distribution, which can enhance the GFA by increasing the structural incompatibility with the competing crystalline phases.
On the origin of bulk glass forming ability in Cu-Hf, Zr alloys
NASA Astrophysics Data System (ADS)
Ristić, Ramir; Zadro, Krešo; Pajić, Damir; Figueroa, Ignacio A.; Babić, Emil
2016-04-01
Understanding the formation of bulk metallic glasses (BMG) in metallic systems and finding a reliable criterion for selection of BMG compositions are among the most important issues in condensed-matter physics and material science. Using the results of magnetic susceptibility measurements performed on both amorphous and crystallized Cu-Hf alloys (30-70 at% Cu) we find a correlation between the difference in magnetic susceptibilities of corresponding glassy and crystalline alloys and the variation in the glass forming ability (GFA) in these alloys. Since the same correlation can be inferred from data for the properties associated with the electronic structure of Cu-Zr alloys, it seems quite general and may apply to other glassy alloys based on early and late transition metals. This correlation is plausible from the free-energy considerations and provides a simple way to select the compositions with high GFA.
NASA Astrophysics Data System (ADS)
Lu, Z. P.; Liu, C. T.; Thompson, J. R.; Porter, W. D.
2004-06-01
Recent advancement in bulk metallic glasses, whose properties are usually superior to their crystalline counterparts, has stimulated great interest in fabricating bulk amorphous steels. While a great deal of effort has been devoted to this field, the fabrication of structural amorphous steels with large cross sections has remained an alchemist’s dream because of the limited glass-forming ability (GFA) of these materials. Here we report the discovery of structural amorphous steels that can be cast into glasses with large cross-section sizes using conventional drop-casting methods. These new steels showed interesting physical, magnetic, and mechanical properties, along with high thermal stability. The underlying mechanisms for the superior GFA of these materials are discussed.
NASA Astrophysics Data System (ADS)
Kumar, Mohit
The unique set of mechanical and magnetic properties possessed by metallic glasses has attracted a lot of recent scientific and technological interest. The development of new metallic glass alloys with improved manufacturability, enhanced properties and higher ductility relies on the fundamental understanding of the interconnections between their atomic structure, glass forming ability (GFA), transport properties, and elastic and plastic deformation mechanisms. This thesis is focused on finding these atomic structure-property relationships in Cu-Zr BMGs using molecular dynamics simulations. In the first study described herein, molecular dynamics simulations of the rapid solidification process over the Cu-Zr compositional domain were conducted to explore inter-dependencies of atomic transport and fragility, elasticity and structural ordering, and GFA. The second study investigated the atomic origins of serration events, which is the characteristic plastic deformation behaviour in BMGs. The combined results of this work suggest that GFA and ductility of metallic glasses could be compositionally tuned.
Crystal genes in a marginal glass-forming system of Ni 50Zr 50
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wen, T. Q.; Tang, L.; Sun, Y.
Glass-forming motifs with B2 traits are found. A perfect Ni-centered B33 motif deteriorates the glass-forming ability of Ni 50Zr 50. The marginal glass-forming ability (GFA) of binary Ni-Zr system is an issue to be explained considering the numerous bulk metallic glasses (BMGs) found in the Cu-Zr system. Using molecular dynamics, the structures and dynamics of Ni 50Zr 50 metallic liquid and glass are investigated at the atomistic level. To achieve a well-relaxed glassy sample, sub-T g annealing method is applied and the final sample is closer to the experiments than the models prepared by continuous cooling. With the state-of-the-art structuralmore » analysis tools such as cluster alignment and pair-wise alignment methods, two glass-forming motifs with some mixed traits of the metastable B2 crystalline phase and the crystalline Ni-centered B33 motif are found to be dominant in the undercooled liquid and glass samples. A new chemical order characterization on each short-range order (SRO) structure is accomplished based on the cluster alignment method. The significant amount of the crystalline motif and the few icosahedra in the glassy sample deteriorate the GFA.« less
Crystal genes in a marginal glass-forming system of Ni 50Zr 50
Wen, T. Q.; Tang, L.; Sun, Y.; ...
2017-10-17
Glass-forming motifs with B2 traits are found. A perfect Ni-centered B33 motif deteriorates the glass-forming ability of Ni 50Zr 50. The marginal glass-forming ability (GFA) of binary Ni-Zr system is an issue to be explained considering the numerous bulk metallic glasses (BMGs) found in the Cu-Zr system. Using molecular dynamics, the structures and dynamics of Ni 50Zr 50 metallic liquid and glass are investigated at the atomistic level. To achieve a well-relaxed glassy sample, sub-T g annealing method is applied and the final sample is closer to the experiments than the models prepared by continuous cooling. With the state-of-the-art structuralmore » analysis tools such as cluster alignment and pair-wise alignment methods, two glass-forming motifs with some mixed traits of the metastable B2 crystalline phase and the crystalline Ni-centered B33 motif are found to be dominant in the undercooled liquid and glass samples. A new chemical order characterization on each short-range order (SRO) structure is accomplished based on the cluster alignment method. The significant amount of the crystalline motif and the few icosahedra in the glassy sample deteriorate the GFA.« less
Structural origin underlying poor glass forming ability of Al metallic glass
NASA Astrophysics Data System (ADS)
Li, F.; Liu, X. J.; Hou, H. Y.; Chen, G.; Chen, G. L.
2011-07-01
We performed molecular dynamics simulations to study the glass formation and local atomic structure of rapidly quenched Al. Both potential energy and structural parameters indicate that the glass transition temperature of amorphous Al is as low as 300 K, which may lead to the poor thermal stability of the amorphous Al as it is prone to crystallize even at room temperature. Voronoi polyhedra analysis reveals that the most popular polyhedron is the deformed body-centered cubic (bcc) cluster characterized by the index < 0, 3, 6, 4 > in the amorphous Al, while the icosahedron with the index < 0, 0, 12, 0 > is always predominant in bulk metallic glass formers with excellent glass forming ability (GFA). Moreover, these deformed-bcc short-range orders can make up medium-range orders via the linkage of vertex-, edge-, face-, intercrossed-shared atoms, which are believed to more easily transform into face-centered cubic (fcc) Al nanocrystal compared with the icosahedral clusters in terms of the symmetrical similarity between bcc and fcc structures. This finding could unveil the structural origin of poor GFA of Al-based alloys.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shi, X. M.; Wang, X. D., E-mail: wangxd@zju.edu.cn, E-mail: jiangjz@zju.edu.cn; Yu, Q.
The atomic structures of Al{sub 89}Y{sub 11}, Al{sub 90}Y{sub 6.5}La{sub 3.5}, and Al{sub 82.8}Y{sub 6.07}Ni{sub 8}La{sub 3.13} metallic glasses have been studied by using high energy X-ray diffraction, X-ray absorption fine structure combined with the ab initio molecular dynamics and reverse Monte Carlo simulations. It is demonstrated that the partial replacement of Y atoms by La has limited improvement of the glass forming ability (GFA), although La atoms reduce the ordering around Y atoms and also the fractions of icosahedron-like polyhedra centered by Al atoms. In contrast, Ni atoms can significantly improve the GFA, which are inclined to locate inmore » the shell of polyhedra centered by Al, Y, and La atoms, mainly forming Ni-centered icosahedron-like polyhedra to enhance the spatial connectivity between clusters and suppress the crystallization.« less
NASA Astrophysics Data System (ADS)
Yazici, Ziya Ozgur; Hitit, Aytekin; Yalcin, Yilmaz; Ozgul, Metin
2016-01-01
Effect of Cu and Si substitutions for Co and B on the glass forming ability (GFA) of Co(43-x)CuxFe20Ta5.5B(31.5-x)Siy (x=0-1.5 and y=5-10) were systematically investigated by X-ray diffraction, optical microscopy, scanning electron microscopy, and differential scanning calorimetry. In order to evaluate the contribution of copper and silicon, appropriate amounts of copper and silicon were individually introduced to the base alloy composition. By using the effects of copper and silicon together, significant enhancement was obtained and the critical casting thickness (CCT) of the base alloy was increased three times from 2 mm to 6 mm. Moreover, mechanical properties of the alloys were examined by compression tests and Vickers hardness measurements. The compression test results revealed that the glassy alloys having enhanced GFA shows high strength of about 3500-4000 MPa. In addition, existence of (Co,Fe)2B and (Co,Fe)20.82Ta2.18B6 crystalline phases in glassy matrix influences the hardnesses of the alloys compared to monolitic glassy structure having hardness of about 1200 Hv.
NASA Astrophysics Data System (ADS)
He, MengKe; Zhang, Yi; Xia, Lei; Yu, Peng
2017-07-01
We studied thermal stability and its relationship to the glass-forming ability (GFA) of the Ni62Nb38- x Ta x ( x=5, 10, 15, 20, 25) bulk metallic glasses (BMG) from a kinetic point of view. By fitting the heating-rate dependence of glass transition temperature ( T g onset) and crystallization temperatures ( T x onset and T x peak) of the Ni62Nb38- x Ta x BMG using the Vogel-Fulcher-Tammann (VFT) equation, we obtained the ideal glass transition and crystallization temperatures ( T g 0 and T x 0) and the fragility parameter ( m), and also constructed continuous heating transition (CHT) diagrams for crystallization of the BMG. The CHT diagrams of the BMG indicate enhanced thermal stability by Ta addition; the T g 0 as well as the T x 0 also illustrates this improved stability limit. The compositional dependence of m, which agrees well with that of the reduced glass-transition temperature, indicates a strong correlation between liquid fragility and glass-forming ability in the present alloy system. These results provide new evidence for understanding thermal stability, liquid fragility, and GFA in BMG.
Baghel, Shrawan; Cathcart, Helen; Redington, Wynette; O'Reilly, Niall J
2016-07-01
Amorphous drug formulations have great potential to enhance solubility and thus bioavailability of BCS class II drugs. However, the higher free energy and molecular mobility of the amorphous form drive them towards the crystalline state which makes them unstable. Accurate determination of the crystallization tendency/kinetics is the key to the successful design and development of such systems. In this study, dipyridamole (DPM) and cinnarizine (CNZ) have been selected as model compounds. Thermodynamic fragility (mT) was measured from the heat capacity change at the glass transition temperature (Tg) whereas dynamic fragility (mD) was evaluated using methods based on extrapolation of configurational entropy to zero [Formula: see text] , and heating rate dependence of Tg [Formula: see text] . The mean relaxation time of amorphous drugs was calculated from the Vogel-Tammann-Fulcher (VTF) equation. Furthermore, the correlation between fragility and glass forming ability (GFA) of the model drugs has been established and the relevance of these parameters to crystallization of amorphous drugs is also assessed. Moreover, the crystallization kinetics of model drugs under isothermal conditions has been studied using Johnson-Mehl-Avrami (JMA) approach to determine the Avrami constant 'n' which provides an insight into the mechanism of crystallization. To further probe into the crystallization mechanism, the non-isothermal crystallization kinetics of model systems were also analysed by statistically fitting the crystallization data to 15 different kinetic models and the relevance of model-free kinetic approach has been established. The crystallization mechanism for DPM and CNZ at each extent of transformation has been predicted. The calculated fragility, glass forming ability (GFA) and crystallization kinetics are found to be in good correlation with the stability prediction of amorphous solid dispersions. Thus, this research work involves a multidisciplinary approach to establish fragility, GFA and crystallization kinetics as stability predictors for amorphous drug formulations. Copyright © 2016 Elsevier B.V. All rights reserved.
A novel parameter to describe the glass-forming ability of alloys
DOE Office of Scientific and Technical Information (OSTI.GOV)
Park, E. S.; Ryu, C. W.; Kim, W. T.
2015-08-14
In this paper, we propose a new parameter for glass-forming ability (GFA) based on the combination of thermodynamic (stability of stable and metastable liquids by ΔT{sub m} = T{sub m}{sup mix} − T{sub l} and ΔT{sub x} = T{sub x} − T{sub g}, respectively) and kinetic (resistance to crystallization by T{sub x}) aspects for glass formation. The parameter is defined as ε = (ΔT{sub m} + ΔT{sub x} + T{sub x})/T{sub m}{sup mix} without directly adding T{sub g} while considering the whole temperature range for glass formation up to T{sub m}{sup mix}, which reflects the relative position of crystallization curve in continuous cooling transformation diagram. The relationship between the εmore » parameter and critical cooling rate (R{sub c}) or maximum section thickness for glass formation (Z{sub max}) clearly confirms that the ε parameter exhibits a better correlation with GFA than other commonly used GFA parameters, such as ΔT{sub x} (=T{sub x} − T{sub g}), K (=[T{sub x} − T{sub g}]/[T{sub l} − T{sub x}]), ΔT*(=(T{sub m}{sup mix} − T{sub l})/T{sub m}{sup mix}), T{sub rg} (=T{sub g}/T{sub l}), and γ (=[T{sub x}]/[T{sub l} + T{sub g}]). The relationship between the ε parameter and R{sub c} or Z{sub max} is also formulated and evaluated in the study. The results suggest that the ε parameter can effectively predict R{sub c} and Z{sub max} for various glass-forming alloys, which would permit more widespread uses of these paradigm-shifting materials in a variety of industries.« less
Sun, Jianguo; Peng, Ying; Wu, Hui; Zhang, Xueyuan; Zhong, Yunxi; Xiao, Yanan; Zhang, Fengyi; Qi, Huanhuan; Shang, Lili; Zhu, Jianping; Sun, Yue; Liu, Ke; Liu, Jinghan; A, Jiye; Ho, Rodney J Y; Wang, Guangji
2015-05-01
Guanfu base A (GFA) is a novel heterocyclic antiarrhythmic drug isolated from Aconitum coreanum (Lèvl.) rapaics and is currently in a phase IV clinical trial in China. However, no study has investigated the influence of GFA on cytochrome P450 (P450) drug metabolism. We characterized the potency and specificity of GFA CYP2D inhibition based on dextromethorphan O-demethylation, a CYP2D6 probe substrate of activity in human, mouse, rat, dog, and monkey liver microsomes. In addition, (+)-bufuralol 1'-hydroxylation was used as a CYP2D6 probe for the recombinant form (rCYP2D6), 2D1 (rCYP2D1), and 2D2 (rCYP2D2) activities. Results show that GFA is a potent noncompetitive inhibitor of CYP2D6, with inhibition constant Ki = 1.20 ± 0.33 μM in human liver microsomes (HLMs) and Ki = 0.37 ± 0.16 μM for the human recombinant form (rCYP2D6). GFA is also a potent competitive inhibitor of CYP2D in monkey (Ki = 0.38 ± 0.12 μM) and dog (Ki = 2.4 ± 1.3 μM) microsomes. However, GFA has no inhibitory activity on mouse or rat CYP2Ds. GFA did not exhibit any inhibition activity on human recombinant CYP1A2, 2A6, 2C8, 2C19, 3A4, or 3A5, but showed slight inhibition of 2B6 and 2E1. Preincubation of HLMs and rCYP2D6 resulted in the inactivation of the enzyme, which was attenuated by GFA or quinidine. Beagle dogs treated intravenously with dextromethorphan (2 mg/ml) after pretreatment with GFA injection showed reduced CYP2D metabolic activity, with the Cmax of dextrorphan being one-third that of the saline-treated group and area under the plasma concentration-time curve half that of the saline-treated group. This study suggests that GFA is a specific CYP2D6 inhibitor that might play a role in CYP2D6 medicated drug-drug interaction. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.
GfaPy: a flexible and extensible software library for handling sequence graphs in Python.
Gonnella, Giorgio; Kurtz, Stefan
2017-10-01
GFA 1 and GFA 2 are recently defined formats for representing sequence graphs, such as assembly, variation or splicing graphs. The formats are adopted by several software tools. Here, we present GfaPy, a software package for creating, parsing and editing GFA graphs using the programming language Python. GfaPy supports GFA 1 and GFA 2, using the same interface and allows for interconversion between both formats. The software package provides a simple interface for custom record types, which is an important new feature of GFA 2 (compared to GFA 1). This enables new applications of the format. GfaPy is available open source at https://github.com/ggonnella/gfapy and installable via pip. gonnella@zbh.uni-hamburg.de. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com
Effects of Zr and Si on the Glass Forming Ability and Compressive Properties of Ti-Cu-Co-Sn Alloys
NASA Astrophysics Data System (ADS)
Wang, Tan; Wu, Yidong; Si, Jiajia; Hui, Xidong
2015-06-01
To succeed in finding novel Ti-based bulk metallic glasses, which are free from Be, Ni, and noble metallic elements, a comprehensive study was performed on the effects of Zr and Si on the microstructural evolution, glass-forming ability (GFA), and mechanical properties of Ti46Cu44- x Zr x Co7Sn3 ( x = 0, 5, 10, 12.5, and 16 at. pct) and Ti46Cu31.5Zr12.5- x Co7Sn3Si x ( x = 0.5, 1, and 1.5 at. pct) alloys. It is shown that with the increase of Zr, the sequence of phase formation is β-Ti + α-Ti + (Ti, Zr)3Cu4 ⇒ β-Ti + α-Ti + TiCu ⇒ β-Ti + Ti2Cu + glass ⇒ glass ⇒ β-Ti + Ti2Cu + TiCuSn. The quinary Ti-Zr-Cu-Co-Sn alloy with 12.5 pct Zr exhibits the best GFA. The addition of 1 pct Si results in the improvement of the critical size of glassy rods up to 3 mm in diameter. The yield stress and Young's modulus of Z-series alloys increases, and the plastic strain decreases with the addition of Zr. The yield stress and ultimate compression stress of Ti46Zr11.5Cu31.5Co7Sn3Si1 glassy alloy reach 2477.9 and 2623.3 MPa, respectively. It was found that the addition of Si promotes the generation and multiplication of shear bands, resulting in certain plasticity in these kinds of glassy alloys.
Shimoyama, Ami; Kido, Shoko; Kinekawa, Yoh-ichi; Doi, Yukio
2008-10-08
The water extract of guar meal ( Cyamopsis tetragonolobus) was examined for its foamability. Compared with egg white, the extract showed an extraordinary foam stability: no drainage after 3 h of standing in contrast to 65% drainage for egg white at the same protein concentration. The acid-precipitated protein from the extract was responsible for the high foamability and designated guar foaming albumin (GFA). The foaming activity of GFA was 20 times higher than that of egg white. GFA consisted of two subunits with molecular masses of 6 and 11 kDa linked to each other through disulfide bonds. The cleavage of disulfide bonds in GFA affected the foamability only slightly. GFA remarkably decreased the surface tension of water at low protein concentrations. Immunoblotting analysis demonstrated that GFA did not react to the antisera from allergic patients against plant food. These results suggest that GFA serves as an effective food additive in developing protein-stabilized foam.
Zhao, Bingge; Yang, Bin; Abyzov, Alexander S; Schmelzer, Jürn W P; Rodríguez-Viejo, Javier; Zhai, Qijie; Schick, Christoph; Gao, Yulai
2017-12-13
In this paper, the amorphous Ce 68 Al 10 Cu 20 Co 2 (atom %) alloy was in situ prepared by nanocalorimetry. The high cooling and heating rates accessible with this technique facilitate the suppression of crystallization on cooling and the identification of homogeneous nucleation. Different from the generally accepted notion that metallic glasses form just by avoiding crystallization, the role of nucleation and growth in the crystallization behavior of amorphous alloys is specified, allowing an access to the ideal metallic glass free of nuclei. Local atomic configurations are fundamentally significant to unravel the glass forming ability (GFA) and phase transitions in metallic glasses. For this reason, isothermal annealing near T g from 0.001 s to 25,000 s following quenching becomes the strategy to tune local atomic configurations and facilitate an amorphous alloy, a mixed glassy-nanocrystalline state, and a crystalline sample successively. On the basis of the evolution of crystallization enthalpy and overall latent heat on reheating, we quantify the underlying mechanism for the isothermal nucleation and crystallization of amorphous alloys. With Johnson-Mehl-Avrami method, it is demonstrated that the coexistence of homogeneous and heterogeneous nucleation contributes to the isothermal crystallization of glass. Heterogeneous rather than homogeneous nucleation dominates the isothermal crystallization of the undercooled liquid. For the mixed glassy-nanocrystalline structure, an extraordinary kinetic stability of the residual glass is validated, which is ascribed to the denser packed interface between amorphous phase and ordered nanocrystals. Tailoring the amorphous structure by nanocalorimetry permits new insights into unraveling GFA and the mechanism that correlates local atomic configurations and phase transitions in metallic glasses.
NASA Astrophysics Data System (ADS)
Gupta, Nupur; Khanna, Atul; Gonzàlez, Fernando; Iordanova, Reni
2017-05-01
Tellurite and borotellurite glasses containing Bi2O3 and TiO2 were prepared and structure-property correlations were carried out by density measurements, X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Raman and UV-visible spectroscopy. Titanium tellurite glasses require high melt-cooling rates and were fabricated by splat quenching. On adding B2O3, the glass forming ability (GFA) enhances, and glasses could be synthesized at lower quenching rates. The density of glasses shows a direct correlation with molecular mass of the constituents. UV-visible studies were used to determine the optical band gap and refractive index. Raman studies found that the co-ordination number of tellurium ions with oxygen (NTe-O) decreases with the increase in B2O3 as well as Bi2O3 content while, TiO2 produce only a small decrease in NTe-O, which explains the lower GFA of titanium tellurite glasses that do not contain Bi2O3 and B2O3. DSC studies show that the glass transition temperature (Tg) increases with B2O3 and TiO2 concentrations and that Tg correlates well with bond enthalpy of the metal oxides.
NASA Astrophysics Data System (ADS)
Zhou, Z.; Wang, L.; He, D. Y.; Wang, F. C.; Liu, Y. B.
2011-01-01
A Fe48Cr15Mo14C15B6Y2 alloy with high glass forming ability (GFA) was selected to prepare amorphous metallic coatings by atmospheric plasma spraying (APS). The as-deposited coatings present a dense layered structure and low porosity. Microstructural studies show that some nanocrystals and a fraction of yttrium oxides formed during spraying, which induced the amorphous fraction of the coatings decreasing to 69% compared with amorphous alloy ribbons of the same component. High thermal stability enables the amorphous coatings to work below 910 K without crystallization. The results of electrochemical measurement show that the coatings exhibit extremely wide passive region and relatively low passive current density in 3.5% NaCl and 1 mol/L HCl solutions, which illustrate their superior ability to resist localized corrosion. Moreover, the corrosion behavior of the amorphous coatings in 1 mol/L H2SO4 solution is similar to their performance under conditions containing chloride ions, which manifests their flexible and extensive ability to withstand aggressive environments.
Qi, Zhen-Lan; Wang, Zi; Li, Wei; Hou, Jin-Gang; Liu, Ying; Li, Xin-Dian; Li, Hui-Ping; Wang, Ying-Ping
2017-09-01
Cisplatin is an effective anticancer chemotherapeutic agent, but the use of cisplatin in the clinic is severely limited by side effects. Nephrotoxicity is a major factor that contributes to the side effects of cisplatin chemotherapy. The aim of this research was to survey the nephroprotective effects of anthocyanin from the fruits of Panax ginseng (GFA) in a murine model of cisplatin-induced acute kidney injury. We observed that pretreatment with GFA attenuated cisplatin-induced elevations in blood urea nitrogen and creatinine levels and histopathological injury induced by cisplatin. The formation of kidney malondialdehyde, heme oxygenase-1, cytochrome P450 E1 and 4-hydroxynonenal with a concomitant reduction in reduced glutathione was also inhibited by GFA, while the activities of kidney superoxide dismutase and catalase were all increased. GFA also inhibited the increase in serum tumour necrosis factor-α and interleukin-1β induced by cisplatin. In addition, the levels of induced nitric oxide synthase and cyclooxygenase-2 were suppressed by GFA. Furthermore, GFA supplementation inhibited the activation of apoptotic pathways by increasing B cell lymphoma 2 and decreasing Bcl2-associated X protein expression. In conclusion, the findings from the present investigation demonstrate that GFA pre-administration can significantly prevent cisplatin-induced nephrotoxicity, which may be related to its antioxidant, anti-apoptotic and antiinflammatory effects. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Calorimetric study of tellurium rich Se-Te-Sn glasses
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heera, Pawan, E-mail: pawanheera@yahoo.com; Govt. College Amb, Himachal Pradesh 177203; Kumar, Anup
2016-05-23
We report the calorimetric study of amorphous Se{sub 30}Te{sub 70-x} Sn{sub x} alloys for x= 0, 1.5, 2.5, 4.5 in terms of kinetic parameters. The DSC curves recorded at four different heating rates are analyzed to determine the transition temperatures, activation energy, thermal stability, glass forming ability. The crystallization process has been investigated using Kissinger, Matusita, Augis and Bennett, and Gao and Wang models. Various kinetic parameters have been calculated for a better understanding of the growth mechanism. The glass transition temperatures T{sub g}, onset crystallization T{sub c}, peak crystallization T{sub p}, and melting temperature T{sub m} are found tomore » increase with the increase in Sn content. The system under investigation is found to be thermally stable for at lower at% of Sn. The values of parameters H{sub R}, H{sub w}, and S indicate that Glass forming ability (GFA) decays with an increase in Sn content.« less
Improved Gravitation Field Algorithm and Its Application in Hierarchical Clustering
Zheng, Ming; Sun, Ying; Liu, Gui-xia; Zhou, You; Zhou, Chun-guang
2012-01-01
Background Gravitation field algorithm (GFA) is a new optimization algorithm which is based on an imitation of natural phenomena. GFA can do well both for searching global minimum and multi-minima in computational biology. But GFA needs to be improved for increasing efficiency, and modified for applying to some discrete data problems in system biology. Method An improved GFA called IGFA was proposed in this paper. Two parts were improved in IGFA. The first one is the rule of random division, which is a reasonable strategy and makes running time shorter. The other one is rotation factor, which can improve the accuracy of IGFA. And to apply IGFA to the hierarchical clustering, the initial part and the movement operator were modified. Results Two kinds of experiments were used to test IGFA. And IGFA was applied to hierarchical clustering. The global minimum experiment was used with IGFA, GFA, GA (genetic algorithm) and SA (simulated annealing). Multi-minima experiment was used with IGFA and GFA. The two experiments results were compared with each other and proved the efficiency of IGFA. IGFA is better than GFA both in accuracy and running time. For the hierarchical clustering, IGFA is used to optimize the smallest distance of genes pairs, and the results were compared with GA and SA, singular-linkage clustering, UPGMA. The efficiency of IGFA is proved. PMID:23173043
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lv, Peng; Wang, Zhong-min, E-mail: zmwang@guet.edu.cn; Zhang, Huai-gang
2013-12-15
Mg{sub 60}Ni{sub 30}La{sub 10−x}Co{sub x} (x = 0, 4) amorphous alloys were prepared by rapid solidification, using a melt-spinning technique. X-ray diffraction and differential scanning calorimetry analysis were employed to measure their microstructure, thermal stability and glass-forming ability, and hydrogen storage properties were studied by means of PCTPro2000. Based on differential scanning calorimetry results, their glass-forming ability and thermal stability were investigated by Kissinger method, Lasocka curves and atomic cluster model, respectively. The results indicate that glass-forming ability, thermal properties and hydrogen storage properties in the Mg-rich corner of Mg–Ni–La–Co system alloys were enhanced by Co substitution for La. Itmore » can be found that the smaller activation energy (ΔΕ) and frequency factor (υ{sub 0}), the bigger value of B (glass transition point in Lasocka curves), and higher glass-forming ability of Mg–Ni–La–Co alloys would be followed. In addition, atomic structure parameter (λ), deduced from atomic cluster model is valuable in the design of Mg–Ni–La–Co system alloys with good glass-forming ability. With an increase of Co content from 0 to 4, the hydrogen desorption capacity within 4000 s rises from 2.25 to 2.85 wt.% at 573 K. - Highlights: • Amorphous Mg{sub 60}Ni{sub 30}La{sub 10−x}Co{sub x} (x = 0 and 4) alloys were produced by melt spinning. • The GFA and hydrogen storage properties were enhanced by Co substitution for La. • With an increase of Co content, the hydrogen desorption capacity rises at 573 K.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xia, L., E-mail: xialei@shu.edu.cn; Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hom; Tang, M. B.
2014-06-14
Gd{sub 55}Al{sub 20}Co{sub 20}Ni{sub 5} bulk metallic glass (BMG) was synthesized by minor Ni substitution for Co in the Gd{sub 55}Al{sub 20}Co{sub 25} BMG in which excellent glass forming ability (GFA) and magneto-caloric effect were reported previously. The Gd{sub 55}Al{sub 20}Ni{sub 20}Co{sub 5} amorphous rod has a similar GFA to the Gd{sub 55}Al{sub 20}Co{sub 25} BMG but exhibits better magnetic properties. The peak value of magnetic entropy change (−ΔS{sub m}{sup peak}) of the Gd{sub 55}Al{sub 20}Co{sub 20}Ni{sub 5} BMG is 9.8 Jkg{sup −1} K{sup −1}. The field dependence of −ΔS{sub m}{sup peak} follows a −ΔS{sub m}{sup peak}∝H{sup 0.85} relationship. Themore » adiabatic temperature rise of the rod is 4.74 K under 5 T and is larger than of other BMGs previously reported. The improved magnetic properties were supposed to be induced by the enhanced interaction between 4f electron in the rare-earth and 3d electron in the transition metal elements by means of a minor Ni substitution for Co.« less
NASA Astrophysics Data System (ADS)
Tahiri, M.; Hasnaoui, A.; Sbiaai, K.
2018-03-01
In this work, we employed molecular dynamics (MD) simulations to study Ti-Al metallic glasses (MGs) using the embedded atom method (EAM) potential to model the atomic interaction with different compositions. The results showed evidence of the metallic glass formation induced by the split occurring in the second peak of the radial distribution function (RDF) curves implying both Ti and Al atoms. The common neighbor analysis (CNA) method confirmed the presence of the icosahedral clusters with a maximum amount observed for an alloy with 75 pct of Al. Analysis of coordination numbers (CNs) indicated that the total CNs are nearly unchanged in these systems. Finally, Voronoi tessellation analyses (VTA) showed a higher value of the number of icosahedral units at Ti25Al75 composition. This specific composition represents a nearby peritectic point localized at a low melting point in the Ti-Al binary phase diagram. The glass forming ability (GFA) becomes important when the fraction of Al increases by forming and connecting "icosahedral-like" clusters (12-coordinated <0, 0, 12, 0> and 13-coordinated <0, 1, 10, 2>) and by playing a main role in the structure stability of the Ti-Al MGs.
NASA Astrophysics Data System (ADS)
Tahiri, M.; Hasnaoui, A.; Sbiaai, K.
2018-06-01
In this work, we employed molecular dynamics (MD) simulations to study Ti-Al metallic glasses (MGs) using the embedded atom method (EAM) potential to model the atomic interaction with different compositions. The results showed evidence of the metallic glass formation induced by the split occurring in the second peak of the radial distribution function (RDF) curves implying both Ti and Al atoms. The common neighbor analysis (CNA) method confirmed the presence of the icosahedral clusters with a maximum amount observed for an alloy with 75 pct of Al. Analysis of coordination numbers (CNs) indicated that the total CNs are nearly unchanged in these systems. Finally, Voronoi tessellation analyses (VTA) showed a higher value of the number of icosahedral units at Ti25Al75 composition. This specific composition represents a nearby peritectic point localized at a low melting point in the Ti-Al binary phase diagram. The glass forming ability (GFA) becomes important when the fraction of Al increases by forming and connecting "icosahedral-like" clusters (12-coordinated <0, 0, 12, 0> and 13-coordinated <0, 1, 10, 2>) and by playing a main role in the structure stability of the Ti-Al MGs.
Alhalaweh, Amjad; Alzghoul, Ahmad; Mahlin, Denny; Bergström, Christel A S
2015-11-10
Amorphous materials are inherently unstable and tend to crystallize upon storage. In this study, we investigated the extent to which the physical stability and inherent crystallization tendency of drugs are related to their glass-forming ability (GFA), the glass transition temperature (Tg) and thermodynamic factors. Differential scanning calorimetry was used to produce the amorphous state of 52 drugs [18 compounds crystallized upon heating (Class II) and 34 remained in the amorphous state (Class III)] and to perform in situ storage for the amorphous material for 12h at temperatures 20°C above or below the Tg. A computational model based on the support vector machine (SVM) algorithm was developed to predict the structure-property relationships. All drugs maintained their Class when stored at 20°C below the Tg. Fourteen of the Class II compounds crystallized when stored above the Tg whereas all except one of the Class III compounds remained amorphous. These results were only related to the glass-forming ability and no relationship to e.g. thermodynamic factors was found. The experimental data were used for computational modeling and a classification model was developed that correctly predicted the physical stability above the Tg. The use of a large dataset revealed that molecular features related to aromaticity and π-π interactions reduce the inherent physical stability of amorphous drugs. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Cao, Hongbo
In this thesis, the application of the computational thermodynamics has been explored on two subjects, the study of magnesium alloys (Chapter 1-5) and bulk metallic glasses (BMGs) (Chapter 6-9). For the former case, a strategy of experiments coupled with the CALPHAD approach was employed to establish a thermodynamic description of the quaternary system Mg-Al-Ca-Sr focusing on the Mg-rich phase equilibria. Multicomponent Mg-rich alloys based on the MgAl-Ca-Sr system are one of the most promising candidates for the high temperature applications in the transportation industry. The Mg-Al-Ca-Sr quaternary consists of four ternaries and six binaries. Thermodynamic descriptions of all constituent binaries are available in the literature. Thermodynamic descriptions of the two key ternaries, Mg-Al-Sr and Mg-Al-Ca, were obtained by an efficient and reliable methodology, combining computational thermodynamics with key experiments. The obtained thermodynamic descriptions were validated by performing extensive comparisons between the calculations and experimental information. Thermodynamic descriptions of the other two ternaries, MgCa-Sr and Al-Ca-Sr, were obtained by extrapolation. For the later case, a computational thermodynamic strategy was formulated to obtain a minor but optimum amount of additional element into a base alloy to improve its glass forming ability (GFA). This was done through thermodynamically calculating the maximum liquidus depressions caused by various alloying addition (or replacement) schemes. The success of this approach has been examined in two multicomponent systems, Zr-based Zr-Cu-Ni-Al-Ti and Cu-rich Cu-Zr-Ti-Y. For both cases, experimental results showed conclusively that the GFA increases more than 100% from the base alloy to the one with minor but optimal elemental addition. Furthermore, a thermodynamic computational approach was employed to identify the compositions of Zr-Ti-Ni-Cu-Al alloys exhibiting low-lying liquidus surfaces, which tend to favor the BMG formation. Guided by these calculations, several series of new Zr-based alloys with excellent GFA were synthesized. The approach using the thermodynamically calculated liquidus temperatures was proved to be robust in locating BMGs and can be considered as a universal method to predict novel BMGs not only of scientific interest but also potential technological applications.
High thermal stability and sluggish crystallization kinetics of high-entropy bulk metallic glasses
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, M.; Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon; Liu, X. J.
2016-06-28
Metallic glasses are metastable and their thermal stability is critical for practical applications, particularly at elevated temperatures. The conventional bulk metallic glasses (BMGs), though exhibiting high glass-forming ability (GFA), crystallize quickly when being heated to a temperature higher than their glass transition temperature. This problem may potentially be alleviated due to the recent developments of high-entropy (or multi-principle-element) bulk metallic glasses (HE-BMGs). In this work, we demonstrate that typical HE-BMGs, i.e., ZrTiHfCuNiBe and ZrTiCuNiBe, have higher kinetic stability, as compared with the benchmark glass Vitreoy1 (Zr{sub 41.2}Ti{sub 13.8}Cu{sub 12.5}Ni{sub 10}Be{sub 22.5}) with a similar chemical composition. The measured activation energymore » for glass transition and crystallization of the HE-BMGs is nearly twice that of Vitreloy 1. Moreover, the sluggish crystallization region ΔT{sub pl-pf}, defined as the temperature span between the last exothermic crystallization peak temperature T{sub pl} and the first crystallization exothermic peak temperature T{sub pf}, of all the HE-BMGs is much wider than that of Vitreloy 1. In addition, high-resolution transmission electron microscopy characterization of the crystallized products at different temperatures and the continuous heating transformation diagram which is proposed to estimate the lifetime at any temperature below the melting point further confirm high thermal stability of the HE-BMGs. Surprisingly, all the HE-BMGs show a small fragility value, which contradicts with their low GFA, suggesting that the underlying diffusion mechanism in the liquid and the solid of HE-BMGs is different.« less
Structural and chemical orders in N i 64.5 Z r 35.5 metallic glass by molecular dynamics simulation
Tang, L.; Wen, T. Q.; Wang, N.; ...
2018-03-06
The atomic structure of Ni 64.5Zr 35.5 metallic glass has been investigated by molecular dynamics (MD) simulations. The calculated structure factors from the MD glassy sample at room temperature agree well with the X-ray diffraction (XRD) and neutron diffraction (ND) experimental data. Using the pairwise cluster alignment and clique analysis methods, we show that there are three types dominant short-range order (SRO) motifs around Ni atoms in the glass sample of Ni 64.5Zr 35.5, i.e., Mixed- Icosahedron(ICO)-Cube, Twined-Cube and icosahedron-like clusters. Furthermore, chemical order and medium-range order (MRO) analysis show that the Mixed-ICOCube and Twined-Cube clusters exhibit the characteristics ofmore » the crystalline B2 phase. In conclusion, our simulation results suggest that the weak glass-forming ability (GFA) of Ni 64.5Zr 35.5 can be attributed to the competition between the glass forming ICO SRO and the crystalline Mixed-ICO-Cube and Twined-Cube motifs.« less
Structural and chemical orders in N i 64.5 Z r 35.5 metallic glass by molecular dynamics simulation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tang, L.; Wen, T. Q.; Wang, N.
The atomic structure of Ni 64.5Zr 35.5 metallic glass has been investigated by molecular dynamics (MD) simulations. The calculated structure factors from the MD glassy sample at room temperature agree well with the X-ray diffraction (XRD) and neutron diffraction (ND) experimental data. Using the pairwise cluster alignment and clique analysis methods, we show that there are three types dominant short-range order (SRO) motifs around Ni atoms in the glass sample of Ni 64.5Zr 35.5, i.e., Mixed- Icosahedron(ICO)-Cube, Twined-Cube and icosahedron-like clusters. Furthermore, chemical order and medium-range order (MRO) analysis show that the Mixed-ICOCube and Twined-Cube clusters exhibit the characteristics ofmore » the crystalline B2 phase. In conclusion, our simulation results suggest that the weak glass-forming ability (GFA) of Ni 64.5Zr 35.5 can be attributed to the competition between the glass forming ICO SRO and the crystalline Mixed-ICO-Cube and Twined-Cube motifs.« less
Structural and chemical orders in N i64.5Z r35.5 metallic glass by molecular dynamics simulation
NASA Astrophysics Data System (ADS)
Tang, L.; Wen, T. Q.; Wang, N.; Sun, Y.; Zhang, F.; Yang, Z. J.; Ho, K. M.; Wang, C. Z.
2018-03-01
The atomic structure of N i64.5Z r35.5 metallic glass has been investigated by molecular dynamics (MD) simulations. The calculated structure factors from the MD glassy sample at room temperature agree well with the x-ray diffraction (XRD) and neutron diffraction (ND) experimental data. Using the pairwise cluster alignment and clique analysis methods, we show that there are three types of dominant short-range order (SRO) motifs around Ni atoms in the glass sample of N i64.5Z r35.5 , i.e., mixed-icosahedron(ICO)-cube, intertwined-cube, and icosahedronlike clusters. Furthermore, chemical order and medium-range order (MRO) analysis show that the mixed-ICO-cube and intertwined-cube clusters exhibit the characteristics of the crystalline B2 phase. Our simulation results suggest that the weak glass-forming ability (GFA) of N i64.5Z r35.5 can be attributed to the competition between the glass forming ICO SRO and the crystalline mixed-ICO-cube and intertwined-cube motifs.
Emi-Flective Display Device with Attribute of High Glare-Free-Ambient-Contrast-Ratio
NASA Astrophysics Data System (ADS)
Yang, Bo-Ru; Hsu, Chuan-Wei; Shieh, Han-Ping D.
2007-11-01
We have demonstrated the integration of an organic light emitting device (OLED) and a reflective liquid crystal display (R-LCD) which was termed an emi-flective display. The glare-free-ambient-contrast-ratio (GFA-CR) was used to evaluate the image quality of display devices under ambient light. Through integrating the OLED with R-LCD, the GFA-CR of the device achieved an improvement by a factor of 8 compared with that of the OLED alone. Moreover, the integrated R-LCD showed a GFA-CR of 100:1 within a viewing cone of 20° which can suppress the wash-out of OLED and is more power-saving in the sunlight. Therefore, an emi-flective display is a promising technique for mobile applications.
Chiang, Huey-Ling; Chen, Yu-Jen; Lin, Hsiang-Yuan; Tseng, Wen-Yih Isaac; Gau, Susan Shur-Fen
2017-01-01
Autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) are not only often comorbid but also overlapped in behavioral and cognitive abnormalities. Little is known about whether these shared phenotypes are based on common or different underlying neuropathologies. Therefore, this study aims to examine the disorder-specific alterations in white matter (WM) structural property. The three comparison groups included 23 male adults with ASD (21.4 ± 3.1 years), 32 male adults with ADHD (23.4 ± 3.3 years), and 29 age-matched healthy male controls (22.4 ± 3.3 years). After acquisition of the diffusion spectrum imaging (DSI), whole brain tractography was reconstructed by a tract-based automatic analysis. Generalized fractional anisotropy (GFA) values were computed to indicate tract-specific WM property with adjusted P value < 0.05 for false discovery rate correction. Post hoc analyses revealed that men with ASD exhibited significant lower GFA values than men with ADHD and male controls in six identified fiber tracts: the right arcuate fasciculus, right cingulum (hippocampal part), anterior commissure, and three callosal fibers (ventrolateral prefrontal cortex part, precentral part, superior temporal part). There was no significant difference in the GFA values of any of the fiber tracts between men with ADHD and controls. In men with ASD, the GFA values of the right arcuate fasciculus and right cingulum (hippocampal part) were negatively associated with autistic social-deficit symptoms, and the anterior commissure GFA value was positively correlated with intelligence. This study highlights the disorder-specific alteration of the microstructural property of WM tracts in male adults with ASD. Hum Brain Mapp 38:384-395, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Crystallization kinetics of Mg–Cu–Yb–Ca–Ag metallic glasses
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tsarkov, Andrey A., E-mail: tsarkov@misis.ru; WPI Advanced Institute for Materials Research, Tohoku University, Katahira 2-1-1, Aoba-Ku, Sendai 980-8577; Zanaeva, Erzhena N.
The paper presents research into a Mg–Cu–Yb system based metallic glassy alloys. Metallic glasses were prepared using induction melting and further injection on a spinning copper wheel. The effect of alloying by Ag and Ca on the glass forming ability and the kinetics of crystallization of Mg–Cu–Yb system based alloys were studied. The differential scanning calorimeter and X-ray diffractometer were used to investigate the kinetics of crystallization and the phase composition of the samples. An indicator of glass forming ability, effective activation energy of crystallization, and enthalpy of mixing were calculated. An increase of the Ca and Ag content hasmore » a positive effect on the glass forming ability, the effective activation energy of crystallization, and the enthalpy of mixing. The highest indicators of the glass forming ability and the thermal stability were found for alloys that contain both alloying elements. The Ag addition suppresses precipitation of the Mg{sub 2}Cu phase during crystallization. A dual-phase glassy-nanocrystalline Mg structure was obtained in Mg{sub 65}Cu{sub 25}Yb{sub 10} and Mg{sub 59.5}Cu{sub 22.9}Yb{sub 11}Ag{sub 6.6} alloys after annealing. Bulk samples with a composite glassy-crystalline structure were obtained in Mg{sub 59.5}Cu{sub 22.9}Yb{sub 11}Ag{sub 6.6} and Mg{sub 64}Cu{sub 21}Yb{sub 9.5}Ag{sub 5.5} alloys. A thermodynamic database for the Mg–Cu–Yb–Ca–Ag system was created to compare the process of crystallization of alloys with polythermal sections of the Mg–Cu–Yb–Ca–Ag phase diagram. - Highlights: • New alloy compositions based on Mg–Cu–Yb system were developed and investigated. • Increasing content of Ag and Ca leads to improving GFA. • Bulk samples with a composite glassy-crystalline structure were obtained. • Thermodynamic database for Mg–Cu–Yb–Ca–Ag system was created.« less
Carneiro, Joao A M; Canisso, Igor F; Bandeira, R S; Scheeren, V F C; Freitas-Dell'Aqua, Camila P; Alvarenga, Marco A; Papa, Frederico O; Dell'Aqua, Jose A
2018-05-01
This study aimed to evaluate the antioxidant properties of coenzyme Q10 (CoQ10) during cryopreservation of semen obtained from stallions having good and bad semen freezing ability (GFA vs. BFA, respectively). Forty ejaculates (n = 20 stallions) were split into five centrifugation and five freezing extenders containing different concentrations of CoQ10 (0, 25, 50, 75 and 100 μmols/L). If CoQ10 was added to the centrifugation extender, the freezing extender had no CoQ10 added; similarly, if CoQ10 was added to the freezing extender, the centrifugation extender had no CoQ10. Semen cryopreserved on extenders containing no CoQ10 served as the control. After post-thaw total sperm motility (TM) assessments, the stallions were classified as GFA (i.e., decrease of ≤25% in TM, n = 7) or BFA (i.e., decrease of ≥40% in TM, n = 5). Stallions not fitting (n = 8) this enrollment criteria had samples discarded. After that, two straws for each extender were thawed at 37 °C for 30 s; one straw was immediately used for evaluation of sperm kinetics, plasma membrane integrity, non-capacitated spermatozoa, reactive oxygen species production, mitochondrial activity and lipid peroxidation. The second straw was kept at 37 °C for 30 min and subjected to the same assessments. Expectedly, sperm motility parameters were significantly lower for stallions with BFA. There were no effects of CoQ10 concentration or time for all parameters evaluated in the group with GFA when compared with the control extender (p > 0.05), except lipid peroxidation (p < 0.05). However, stallions with BFA had improved sperm parameters for samples processed with extenders containing CoQ10 (particularly 75 μmols/L) (p < 0.05), except for the reactive oxygen species production and mitochondrial potential (T0) in which there were no differences between the groups (p > 0.05). In summary, 75 μmols/L appears to be the optimal dose of Co-Q10, particularly, when added to the centrifugation extender. Copyright © 2018 Elsevier B.V. All rights reserved.
Generalized five-dimensional dynamic and spectral factor analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
El Fakhri, Georges; Sitek, Arkadiusz; Zimmerman, Robert E.
2006-04-15
We have generalized the spectral factor analysis and the factor analysis of dynamic sequences (FADS) in SPECT imaging to a five-dimensional general factor analysis model (5D-GFA), where the five dimensions are the three spatial dimensions, photon energy, and time. The generalized model yields a significant advantage in terms of the ratio of the number of equations to that of unknowns in the factor analysis problem in dynamic SPECT studies. We solved the 5D model using a least-squares approach. In addition to the traditional non-negativity constraints, we constrained the solution using a priori knowledge of both time and energy, assuming thatmore » primary factors (spectra) are Gaussian-shaped with full-width at half-maximum equal to gamma camera energy resolution. 5D-GFA was validated in a simultaneous pre-/post-synaptic dual isotope dynamic phantom study where {sup 99m}Tc and {sup 123}I activities were used to model early Parkinson disease studies. 5D-GFA was also applied to simultaneous perfusion/dopamine transporter (DAT) dynamic SPECT in rhesus monkeys. In the striatal phantom, 5D-GFA yielded significantly more accurate and precise estimates of both primary {sup 99m}Tc (bias=6.4%{+-}4.3%) and {sup 123}I (-1.7%{+-}6.9%) time activity curves (TAC) compared to conventional FADS (biases=15.5%{+-}10.6% in {sup 99m}Tc and 8.3%{+-}12.7% in {sup 123}I, p<0.05). Our technique was also validated in two primate dynamic dual isotope perfusion/DAT transporter studies. Biases of {sup 99m}Tc-HMPAO and {sup 123}I-DAT activity estimates with respect to estimates obtained in the presence of only one radionuclide (sequential imaging) were significantly lower with 5D-GFA (9.4%{+-}4.3% for {sup 99m}Tc-HMPAO and 8.7%{+-}4.1% for {sup 123}I-DAT) compared to biases greater than 15% for volumes of interest (VOI) over the reconstructed volumes (p<0.05). 5D-GFA is a novel and promising approach in dynamic SPECT imaging that can also be used in other modalities. It allows accurate and precise dynamic analysis while compensating for Compton scatter and cross-talk.« less
Glass Transition Kinetics of 2714A amorphous alloy
NASA Astrophysics Data System (ADS)
Shanker Rao, T.; Lilly Shanker Rao, T.; Shaker, A. M.; Venkataraman, K.
2018-03-01
The present study is related to the kinetics of onset crystallization, Tx and peak crystallization Tp of cobalt based metallic glass 2714A (Co65Si15B14Fe4Ni2) using Differential Scanning Calorimetry (DSC). Non-isothermal measurements were performed at different heating rates (2, 4, 6, 8 and 10 K/min).The experimental results of the crystallization were studied by two most frequently used methods, i.e., Moynihan and Kissinger. The onset crystallization was also studied by VFT and Lasock’s approaches in addition to the above two methods. The activation energy of crystallization Ec was found to be 622.86 and 638.28 kJ/mol and Ex the activation energy of onset crystallization to be 676.34 and 688.93 kJ/mol respectively. Here Tx is used as a substitution of Tg to calculate the fragility index m of the cobalt based metallic glass in the absence of Tg. The fragility index, m which is a measure of glass forming ability (GFA) is also calculated and the value falls between 20 and 60. This indicates the studied metallic glass is an intermediate strong glass.
Fe-based bulk amorphous alloys with iron contents as high as 82 at%
NASA Astrophysics Data System (ADS)
Li, Jin-Feng; Liu, Xue; Zhao, Shao-Fan; Ding, Hong-Yu; Yao, Ke-Fu
2015-07-01
Fe-based bulk amorphous alloys (BAAs) with high Fe contents are advantageous due to their high saturation magnetization and low cost. However, preparing Fe-based BAAs with Fe contents higher than 80 at% is difficult due to their poor glass forming abilities (GFA). In this study, an Fe81P8.5C5.5B2Si3 BAA with a diameter of 1 mm and a saturation magnetization of 1.56 T was successfully prepared using the fluxing and copper mold casting methods. In addition, by introducing a small amount of elemental Mo to the alloy, an Fe82Mo1P6.5C5.5B2Si3 BAA rod with a diameter of 1 mm, a high saturation magnetization of 1.59 T, a high yield stress of 3265 MPa, and a clear plasticity of 1.3% was prepared in the same way. The cost effectiveness and good magnetic properties of these newly-developed Fe-based BAAs with Fe contents as high as 82 at% would be advantageous and promising for industrial applications.
Lin, Jun; Zhu, Jiajun; Gu, Xiaoxia; Wen, Wenjian; Li, Qingshan; Fischer-Brandies, Helge; Wang, Huiming; Mehl, Christian
2011-03-01
This study aimed to investigate the fluoride release properties and the effect on bond strength of two experimental adhesive cements. Synthesized particles of nano-fluorapatite (nano-FA) or nano-fluorohydroxyapatite (nano-FHA) were incorporated into a resin-modified glass ionomer cement (Fuji Ortho LC) and characterized using X-ray diffraction and scanning electron microscopy. Blocks with six different concentrations of nano-FA or nano-FHA were manufactured and their fluoride release properties evaluated by ultraviolet spectrophotometry. The unaltered glass ionomer cement Fuji Ortho LC (GC, control) and the two experimental cements with the highest fluoride release capacities (nano-FA+Fuji Ortho LC (GFA) and nano-FHA+Fuji Ortho LC (GFHA)) were used to bond composite blocks and orthodontic brackets to human enamel. After 24 h water storage all specimens were debonded, measuring the micro-tensile bond strength (μTBS) and the shear bond strength (SBS), respectively. The optimal concentration of added nano-FA and nano-FHA for maximum fluoride release was 25 wt.%, which nearly tripled fluoride release after 70 days compared with the control group. GC exhibited a significantly higher SBS than GFHA/GFA, with GFHA and GFA not differing significantly (P>0.05). The μTBS of GC and GFA were significantly higher than that of GFHA (P≤0.05). The results seem to indicate that the fluoride release properties of Fuji Ortho LC are improved by incorporating nano-FA or nano-FHA, simultaneously maintaining a clinically sufficient bond strength when nano-FA was added. Copyright © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Jenkins, Nathan T.; Thorne, Pamela K.; Martin, Jeffrey S.; Rector, R. Scott; Davis, J. Wade; Laughlin, M. Harold
2014-01-01
We employed next-generation RNA sequencing (RNA-Seq) technology to determine the extent to which exercise training alters global gene expression in skeletal muscle feed arteries and aortic endothelial cells of obese Otsuka Long-Evans Tokushima Fatty (OLETF) rats. Transcriptional profiles of the soleus and gastrocnemius muscle feed arteries (SFA and GFA, respectively) and aortic endothelial cell-enriched samples from rats that underwent an endurance exercise training program (EndEx; n = 12) or a interval sprint training program (IST; n = 12) or remained sedentary (Sed; n = 12) were examined. In response to EndEx, there were 39 upregulated (e.g., MANF) and 20 downregulated (e.g., ALOX15) genes in SFA and 1 upregulated (i.e., Wisp2) and 1 downregulated (i.e., Crem) gene in GFA [false discovery rate (FDR) < 10%]. In response to IST, there were 305 upregulated (e.g., MANF, HSPA12B) and 324 downregulated genes in SFA and 101 upregulated and 66 downregulated genes in GFA, with an overlap of 32 genes between arteries. Furthermore, in aortic endothelial cells, there were 183 upregulated (e.g., eNOS, SOD-3) and 141 downregulated (e.g., ATF3, Clec1b, npy, leptin) genes with EndEx and 71 upregulated and 69 downregulated genes with IST, with an overlap of 35 between exercise programs. Expression of only two genes (Tubb2b and Slc9a3r2) was altered (i.e., increased) by exercise in all three arteries. The finding that both EndEx and IST produced greater transcriptional changes in the SFA compared with the GFA is intriguing when considering the fact that treadmill bouts of exercise are associated with greater relative increases in blood flow to the gastrocnemius muscle compared with the soleus muscle. PMID:24408995
Chiang, Huey-Ling; Chen, Yu-Jen; Lo, Yu-Chun; Tseng, Wen-Yih Isaac; Gau, Susan Shur-Fen
2015-01-01
Background The neural substrate for clinical symptoms and neuropsychological performance in individuals with attention-deficit/hyperactivity disorder (ADHD) has rarely been studied and has yielded inconsistent results. We sought to compare the microstructural property of fibre tracts associated with the prefrontal cortex and its association with ADHD symptoms and a wide range of attention performance in youth with ADHD and healthy controls. Methods We assessed youths with ADHD and age-, sex-, handedness-, coil- and intelligence-matched controls using the Conners’ Continuous Performance Test (CCPT) for attention performance and MRI. The 10 target tracts, including the bilateral frontostriatal tracts (caudate to dorsolateral prefrontal cortex, ventrolateral prefrontal cortex and orbitofrontal cortex), superior longitudinal fasciculus (SLF) and cingulum bundle were reconstructed using diffusion spectrum imaging tractography. We computed generalized fractional anisotropy (GFA) values to indicate tract-specific microstructural property. Results We included 50 youths with ADHD and 50 healthy controls in our study. Youths with ADHD had lower GFA in the left frontostriatal tracts, bilateral SLF and right cingulum bundle and performed worse in the CCPT than controls. Furthermore, alteration of the right SLF GFA was most significantly associated with the clinical symptom of inattention in youths with ADHD. Finally, youths with ADHD had differential association patterns of the 10 fibre tract GFA values with attention performance compared with controls. Limitations Ten of the youths with ADHD were treated with methylphenidate, which may have long-term effects on microstructural property. Conclusion Our study highlights the importance of the SLF, cingulum bundle and frontostriatal tracts for clinical symptoms and attention performance in youths with ADHD and demonstrates the involvement of different fibre tracts in attention performance in these individuals. PMID:25871496
Chiang, Huey-Ling; Chen, Yu-Jen; Lo, Yu-Chun; Tseng, Wen-Yih I; Gau, Susan S
2015-09-01
The neural substrate for clinical symptoms and neuropsychological performance in individuals with attention-deficit/hyperactivity disorder (ADHD) has rarely been studied and has yielded inconsistent results. We sought to compare the microstructural property of fibre tracts associated with the prefrontal cortex and its association with ADHD symptoms and a wide range of attention performance in youth with ADHD and healthy controls. We assessed youths with ADHD and age-, sex-, handedness-, coil- and intelligence-matched controls using the Conners' Continuous Performance Test (CCPT) for attention performance and MRI. The 10 target tracts, including the bilateral frontostriatal tracts (caudate to dorsolateral prefrontal cortex, ventrolateral prefrontal cortex and orbitofrontal cortex), superior longitudinal fasciculus (SLF) and cingulum bundle were reconstructed using diffusion spectrum imaging tractography. We computed generalized fractional anisotropy (GFA) values to indicate tract-specific microstructural property. We included 50 youths with ADHD and 50 healthy controls in our study. Youths with ADHD had lower GFA in the left frontostriatal tracts, bilateral SLF and right cingulum bundle and performed worse in the CCPT than controls. Furthermore, alteration of the right SLF GFA was most significantly associated with the clinical symptom of inattention in youths with ADHD. Finally, youths with ADHD had differential association patterns of the 10 fibre tract GFA values with attention performance compared with controls. Ten of the youths with ADHD were treated with methylphenidate, which may have long-term effects on microstructural property. Our study highlights the importance of the SLF, cingulum bundle and frontostriatal tracts for clinical symptoms and attention performance in youths with ADHD and demonstrates the involvement of different fibre tracts in attention performance in these individuals.
Johnson, N F
1994-01-01
The dissolution rate of glass fibers has been shown to be pH sensitive using in vitro lung fluid simulant models. The current study investigated whether there is a difference in phagosomal pH (ppH) between rat alveolar macrophages (AM) and rat nasal epithelial cells (RNEC) and whether such a difference would influence the dissolution of glass fibers. The ppH was measured in cultured AM and RNEC using flow cytometric, fluorescence-emission rationing techniques with fluorescein-labeled, amorphous silica particles. Glass fiber dissolution was determined in AM and RNEC cultured for 3 weeks with fast dissolving glass fibers (GF-A) or slow dissolving ones (GF-B). The mean diameters of GF-A were 2.7 microns and of GF-B, 2.6 microns, the average length of both fibers was approximately 22 to 25 microns. Dissolution was monitored by measuring the length and diameter of intracellular fibers and estimating the volume, assuming a cylindrical morphology. The ppH of AM was 5.2 to 5.8, and the ppH of RNEC was 7.0 to 7.5. The GF-A dissolved more slowly in RNEC than in AM, and no dissolution was evident in either cell type with GF-B. The volume loss with GF-A after a 3-week culture with AM was 66% compared to 45% for cultured RNEC. These results are different from those obtained using in vitro lung fluid-simulant models where dissolution is faster at higher pH. This difference suggests that dissolution rates of glass fibers in AM should not be applied to the dissolution of fibers in epithelial cells. Images Figure 1. a Figure 1. b Figure 2. a Figure 2. b Figure 3. a Figure 3. b PMID:7882965
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sidorov, V., E-mail: vesidor@mail.ru; Rojkov, I.; Mikhailov, V.
2015-08-17
The influence of small additions of gallium on electric resistivity and magnetic susceptibility of the bulk glass forming Co{sub 47}Fe{sub 20.9}B{sub 21.2}Si{sub 4.6}Nb{sub 6.3} alloy was studied in a wide temperature range up to 1830 K. Gallium atoms were found to increase resistivity but decrease susceptibility of the alloy. The suppositions about clusters surrounding Ga atoms in the melt and new GFA criterion are given.
Riley, Elizabeth
2017-10-01
Background The Gender Feeling Amplitude (GFA) is a 68-item list of words and phrases with which to identify the feelings and severity of a young person's distress regarding their gender identity and gender diversity, and takes ~1min to administer. For this pilot study, 67 adolescents and youth who sought support, confirmation or intervention (either via themselves or their parents) regarding gender diversity or gender transition were given the GFA in a face-to-face meeting before the beginning of an assessment procedure for gender diversity. Forty-three assigned females and 24 assigned males aged between 10 and 20 years were analysed by frequency of item, age and assigned gender. Of the 68 items, those circled by close to 50% or more of the participants were 'self-conscious', 'awkward' and 'don't fit in'. One-third or more circled the words 'shy', 'supported', 'hopeful', 'discomfort', 'as if I'm not being seen properly', 'forced to be something I'm not', 'depressed' and 'stressed'. Comparisons showed some variations in responses by both assigned gender and age, and the discussion includes ways the GFA may be able to assist a health practitioner with explorations of gender diversity and interventions for counselling.
Experimental and QSAR study on the surface activities of alkyl imidazoline surfactants
NASA Astrophysics Data System (ADS)
Kong, Xiangjun; Qian, Chengduo; Fan, Weiyu; Liang, Zupei
2018-03-01
15 alkyl imidazoline surfactants with different structures were synthesized and their critical micelle concentration (CMC) and surface tension under the CMC (σcmc) in aqueous solution were measured at 298 K. 54 kinds of molecular structure descriptors were selected as independent variables and the quantitative structure-activity relationship (QSAR) between surface activities of alkyl imidazoline and molecular structure were built through the genetic function approximation (GFA) method. Experimental results showed that the maximum surface excess of alkyl imidazoline molecules at the gas-liquid interface increased and the area occupied by each surfactant molecule and the free energies of micellization ΔGm decreased with increasing carbon number (NC) of the hydrophobic chain or decreasing hydrophilicity of counterions, which resulted in a CMC and σcmc decrease, while the log CMC and NC had a linear relationship and a negative correlation. The GFA-QSAR model, which was generated by a training set composed of 13 kinds of alkyl imidazoline though GFA method regression analysis, was highly correlated with predicted values and experimental values of the CMC. The correlation coefficient R was 0.9991, which means high prediction accuracy. The prediction error of 2 kinds of alkyl imidazoline CMCs in the Validation Set that quantitatively analyzed the influence of the alkyl imidazoline molecular structure on the CMC was less than 4%.
Extracting quantitative measures from EAP: a small clinical study using BFOR.
Hosseinbor, A Pasha; Chung, Moo K; Wu, Yu-Chien; Fleming, John O; Field, Aaron S; Alexander, Andrew L
2012-01-01
The ensemble average propagator (EAP) describes the 3D average diffusion process of water molecules, capturing both its radial and angular contents, and hence providing rich information about complex tissue microstructure properties. Bessel Fourier orientation reconstruction (BFOR) is one of several analytical, non-Cartesian EAP reconstruction schemes employing multiple shell acquisitions that have recently been proposed. Such modeling bases have not yet been fully exploited in the extraction of rotationally invariant q-space indices that describe the degree of diffusion anisotropy/restrictivity. Such quantitative measures include the zero-displacement probability (P(o)), mean squared displacement (MSD), q-space inverse variance (QIV), and generalized fractional anisotropy (GFA), and all are simply scalar features of the EAP. In this study, a general relationship between MSD and q-space diffusion signal is derived and an EAP-based definition of GFA is introduced. A significant part of the paper is dedicated to utilizing BFOR in a clinical dataset, comprised of 5 multiple sclerosis (MS) patients and 4 healthy controls, to estimate P(o), MSD, QIV, and GFA of corpus callosum, and specifically, to see if such indices can detect changes between normal appearing white matter (NAWM) and healthy white matter (WM). Although the sample size is small, this study is a proof of concept that can be extended to larger sample sizes in the future.
Das, Sreeparna; Mitra, Indrani; Batuta, Shaikh; Niharul Alam, Md; Roy, Kunal; Begum, Naznin Ara
2014-11-01
A series of flavonoid analogues were synthesized and screened for the in vitro antioxidant activity through their ability to quench 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical. The activity of these compounds, measured in comparison to the well-known standard antioxidants (29-32), their precursors (38-42) and other bioactive moieties (38-42) resembling partially the flavone skeleton was analyzed further to develop Quantitative Structure-Activity Relationship (QSAR) models using the Genetic Function Approximation (GFA) technique. Based on the essential structural requirements predicted by the QSAR models, some analogues were designed, synthesized and tested for activity. The predicted and experimental activities of these compounds were well correlated. Flavone analogue 20 was found to be the most potent antioxidant. Copyright © 2014 Elsevier Ltd. All rights reserved.
Lin, Yi-Cheng; Shih, Yao-Chia; Tseng, Wen-Yih I; Chu, Yu-Hsiu; Wu, Meng-Tien; Chen, Ta-Fu; Tang, Pei-Fang; Chiu, Ming-Jang
2014-05-01
Diffusion spectrum imaging (DSI) of MRI can detect neural fiber tract changes. We investigated integrity of cingulum bundle (CB) in patients with mild cognitive impairment (MCI) and early Alzheimer's disease (EAD) using DSI tractography and explored its relationship with cognitive functions. We recruited 8 patients with MCI, 9 with EAD and 15 healthy controls (HC). All subjects received a battery of neuropsychological tests to access their executive, memory and language functions. We used a 3.0-tesla MRI scanner to obtain T1- and T2-weighted images for anatomy and used a pulsed gradient twice-refocused spin-echo diffusion echo-planar imaging sequence to acquire DSI. Patients with EAD performed significantly poorer than the HC on most tests in executive and memory functions. Significantly smaller general fractional anisotropy (GFA) values were found in the posterior and inferior segments of left CB and of the anterior segment of right CB of the EAD compared with those of the HC. Spearman's correlation on the patient groups showed that GFA values of the posterior segment of the left CB were significantly negatively associated with the time used to complete Color Trails Test Part II and positively correlated with performance of the logical memory and visual reproduction. GFA values of inferior segment of bilateral CB were positively associated with the performance of visual recognition. DSI tractography demonstrates significant preferential degeneration of the CB on the left side in patients with EAD. The location-specific degeneration is associated with corresponding declines in both executive and memory functions.
Koch, Paul L.
2017-01-01
Scat is frequently used to study animal diets because it is easy to find and collect, but one concern is that gross fecal analysis (GFA) techniques exaggerate the importance of small-bodied prey to mammalian mesopredator diets. To capitalize on the benefits of scat, we suggest the analysis of scat carbon and nitrogen isotope values (δ13C and δ15N). This technique offers researchers a non-invasive method to gather short-term dietary information. We conducted three interrelated studies to validate the use of isotopic values from coyote scat: 1) we determined tissue-to-tissue apparent C and N isotope enrichment factors (ε13* and ε15*) for coyotes from road kill animals (n = 4); 2) we derived diet-to-scat isotope discrimination factors for coyotes; and 3) we used field collected coyote scats (n = 12) to compare estimates of coyote dietary proportions from stable isotope mixing models with estimates from two GFA techniques. Scat consistently had the lowest δ13C and δ15N values among the tissues sampled. We derived a diet-to-scat Δ13C value of -1.5‰ ± 1.6‰ and Δ15N value of 2.3‰ ± 1.3‰ for coyotes. Coyote scat δ13C and δ15N values adjusted for discrimination consistently plot within the isotopic mixing space created by known dietary items. In comparison with GFA results, we found that mixing model estimates of coyote dietary proportions de-emphasize the importance of small-bodied prey. Coyote scat δ13C and δ15N values therefore offer a relatively quick and non-invasive way to gain accurate dietary information. PMID:28369133
Reid, Rachel E B; Koch, Paul L
2017-01-01
Scat is frequently used to study animal diets because it is easy to find and collect, but one concern is that gross fecal analysis (GFA) techniques exaggerate the importance of small-bodied prey to mammalian mesopredator diets. To capitalize on the benefits of scat, we suggest the analysis of scat carbon and nitrogen isotope values (δ13C and δ15N). This technique offers researchers a non-invasive method to gather short-term dietary information. We conducted three interrelated studies to validate the use of isotopic values from coyote scat: 1) we determined tissue-to-tissue apparent C and N isotope enrichment factors (ε13* and ε15*) for coyotes from road kill animals (n = 4); 2) we derived diet-to-scat isotope discrimination factors for coyotes; and 3) we used field collected coyote scats (n = 12) to compare estimates of coyote dietary proportions from stable isotope mixing models with estimates from two GFA techniques. Scat consistently had the lowest δ13C and δ15N values among the tissues sampled. We derived a diet-to-scat Δ13C value of -1.5‰ ± 1.6‰ and Δ15N value of 2.3‰ ± 1.3‰ for coyotes. Coyote scat δ13C and δ15N values adjusted for discrimination consistently plot within the isotopic mixing space created by known dietary items. In comparison with GFA results, we found that mixing model estimates of coyote dietary proportions de-emphasize the importance of small-bodied prey. Coyote scat δ13C and δ15N values therefore offer a relatively quick and non-invasive way to gain accurate dietary information.
Lo, Yu-Chun; Chen, Yu-Jen; Hsu, Yung-Chin; Tseng, Wen-Yih Isaac; Gau, Susan Shur-Fen
2017-05-01
Autism spectrum disorder (ASD) is a neurodevelopmental disorder with social communication deficits as one of the core symptoms. Recently, a five-level model for the social communication has been proposed in which white matter tracts corresponding to each level of the model are identified. Given that the model for social communication subserves social language functions, we hypothesized that the tract integrity of the model for social communication may be reduced in ASD, and the reduction may be related to social communication deficits. Sixty-two right-handed boys with ASD and 55 typically developing (TD) boys received clinical evaluations, intelligence tests, the Social Communication Questionnaire (SCQ), and MRI scans. Generalized fractional anisotropy (GFA) was measured by diffusion spectrum imaging to indicate the microstructural integrity of the tracts for each level of the social communication model. Group difference in the tract integrity and its relationship with the SCQ subscales of social communication and social interaction were investigated. We found that the GFA values of the superior longitudinal fasciculus III (SLF III, level 1) and the frontal aslant tracts (FAT, level 2) were decreased in ASD compared to TD. Moreover, the GFA values of the SLF III and the FAT were associated with the social interaction subscale in ASD. The tract integrity of the model for social communication is reduced in ASD, and the reduction is associated with impaired social interaction. Our results support that reduced tract integrity of the model for social communication might be a neural substrate of social communication deficits in ASD. © 2016 Association for Child and Adolescent Mental Health.
Wu, Chen-Hao; Hwang, Tzung-Jeng; Chen, Yu-Jen; Hsu, Yun-Chin; Lo, Yu-Chun; Liu, Chih-Min; Hwu, Hai-Gwo; Liu, Chen-Chung; Hsieh, Ming H; Chien, Yi Ling; Chen, Chung-Ming; Tseng, Wen-Yih Isaac
2015-03-01
Trait markers of schizophrenia aid the dissection of the heterogeneous phenotypes into distinct subtypes and facilitate the genetic underpinning of the disease. The microstructural integrity of the white matter tracts could serve as a trait marker of schizophrenia, and tractography-based analysis (TBA) is the current method of choice. Manual tractography is time-consuming and limits the analysis to preselected fiber tracts. Here, we sought to identify a trait marker of schizophrenia from among 74 fiber tracts across the whole brain using a novel automatic TBA method. Thirty-one patients with schizophrenia, 31 unaffected siblings and 31 healthy controls were recruited to undergo diffusion spectrum magnetic resonance imaging at 3T. Generalized fractional anisotropy (GFA), an index reflecting tract integrity, was computed for each tract and compared among the three groups. Ten tracts were found to exhibit significant differences between the groups with a linear, stepwise order from controls to siblings to patients; they included the right arcuate fasciculus, bilateral fornices, bilateral auditory tracts, left optic radiation, the genu of the corpus callosum, and the corpus callosum to the bilateral dorsolateral prefrontal cortices, bilateral temporal poles, and bilateral hippocampi. Posthoc between-group analyses revealed that the GFA of the right arcuate fasciculus was significantly decreased in both the patients and unaffected siblings compared to the controls. Furthermore, the GFA of the right arcuate fasciculus exhibited a trend toward positive symptom scores. In conclusion, the right arcuate fasciculus may be a candidate trait marker and deserves further study to verify any genetic association. © 2014 Wiley Periodicals, Inc.
Lin, H-Y; Gau, S S-F; Huang-Gu, S L; Shang, C-Y; Wu, Y-H; Tseng, W-Y I
2014-06-01
Increased intra-individual variability (IIV) in reaction time (RT) across various tasks is one ubiquitous neuropsychological finding in attention deficit hyperactivity disorder (ADHD). However, neurobiological underpinnings of IIV in individuals with ADHD have not yet been fully delineated. The ex-Gaussian distribution has been proved to capture IIV in RT. The authors explored the three parameters [μ (mu), σ (sigma), τ (tau)] of an ex-Gaussian RT distribution derived from the Conners' continuous performance test (CCPT) and their correlations with the microstructural integrity of the frontostriatal-caudate tracts and the cingulum bundles. We assessed 28 youths with ADHD (8-17 years; 25 males) and 28 age-, sex-, IQ- and handedness-matched typically developing (TD) youths using the CCPT, Wechsler Intelligence Scale for Children, 3rd edition and magnetic resonance imaging (MRI). Microstructural integrity, indexed by generalized fractional anisotropy (GFA), was measured by diffusion spectrum imaging tractrography on a 3-T MRI system. Youths with ADHD had larger σ (s.d. of Gaussian distribution) and τ (mean of exponential distribution) and reduced GFA in four bilateral frontostriatal tracts. With increased inter-stimulus intervals of CCPT, the magnitude of greater τ in ADHD than TD increased. In ADHD youths, the cingulum bundles and frontostriatal integrity were associated with three ex-Gaussian parameters and with μ (mean of Gaussian distribution) and τ, respectively; while only frontostriatal GFA was associated with μ and τ in TD youths. Our findings suggest the crucial role of the integrity of the cingulum bundles in accounting for IIV in ADHD. Involvement of different brain systems in mediating IIV may relate to a distinctive pathophysiological processing and/or adaptive compensatory mechanism.
On the Viability of Diffusion MRI-Based Microstructural Biomarkers in Ischemic Stroke
Boscolo Galazzo, Ilaria; Brusini, Lorenza; Obertino, Silvia; Zucchelli, Mauro; Granziera, Cristina; Menegaz, Gloria
2018-01-01
Recent tract-based analyses provided evidence for the exploitability of 3D-SHORE microstructural descriptors derived from diffusion MRI (dMRI) in revealing white matter (WM) plasticity. In this work, we focused on the main open issues left: (1) the comparative analysis with respect to classical tensor-derived indices, i.e., Fractional Anisotropy (FA) and Mean Diffusivity (MD); and (2) the ability to detect plasticity processes in gray matter (GM). Although signal modeling in GM is still largely unexplored, we investigated their sensibility to stroke-induced microstructural modifications occurring in the contralateral hemisphere. A more complete picture could provide hints for investigating the interplay of GM and WM modulations. Ten stroke patients and ten age/gender-matched healthy controls were enrolled in the study and underwent diffusion spectrum imaging (DSI). Acquisitions at three and two time points (tp) were performed on patients and controls, respectively. For all subjects and acquisitions, FA and MD were computed along with 3D-SHORE-based indices [Generalized Fractional Anisotropy (GFA), Propagator Anisotropy (PA), Return To the Axis Probability (RTAP), Return To the Plane Probability (RTPP), and Mean Square Displacement (MSD)]. Tract-based analysis involving the cortical, subcortical and transcallosal motor networks and region-based analysis in GM were successively performed, focusing on the contralateral hemisphere to the stroke. Reproducibility of all the indices on both WM and GM was quantitatively proved on controls. For tract-based, longitudinal group analyses revealed the highest significant differences across the subcortical and transcallosal networks for all the indices. The optimal regression model for predicting the clinical motor outcome at tp3 included GFA, PA, RTPP, and MSD in the subcortical network in combination with the main clinical information at baseline. Region-based analysis in the contralateral GM highlighted the ability of anisotropy indices in discriminating between groups mainly at tp1, while diffusivity indices appeared to be altered at tp2. 3D-SHORE indices proved to be suitable in probing plasticity in both WM and GM, further confirming their viability as a novel family of biomarkers in ischemic stroke in WM and revealing their potential exploitability in GM. Their combination with tensor-derived indices can provide more detailed insights of the different tissue modulations related to stroke pathology. PMID:29515362
Hierarchical Decentralized Control Strategy for Demand-Side Primary Frequency Response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lian, Jianming; Hansen, Jacob; Marinovici, Laurentiu D.
The Grid Friendlymore » $$^\\textrm{TM}$$ Appliance~(GFA) controller, developed at Pacific Northwest National Laboratory, was designed for the purpose of autonomously switching off appliances by detecting under-frequency events. In this paper, a new frequency responsive load~(FRL) controller is first proposed by extending the functionality of the original GFA controller. The proposed FRL controller can autonomously switch on (or off) end-use loads by detecting over-frequency (or under-frequency) events through local frequency measurement. Then, a hierarchical decentralized control framework is developed for engaging the end-use loads to provide primary frequency response with the proposed FRL controller. The developed framework has several important features that are desirable in terms of providing primary frequency control. It not only exclusively maintains the autonomous operation of the end-use loads, but also effectively overcomes the stability issue associated with high penetration of FRLs. The simulation results illustrate the effectiveness of the developed hierarchical control framework for providing primary frequency response with the proposed FRL controller.« less
[Significance of sex and gender studies for anthropology].
Kirchengast, Sylvia
2004-09-01
The formation of a special working group for gender studies within the German Anthropological Society (GfA) makes necessary a description of history as well as topics of gender studies within science and biological anthropology. In German speaking countries, gender studies are predominantly associated with social and cultural sciences, although very successful working groups belonging to natural sciences already exist. Unfortunately, up to now gender studies within natural sciences are often interpreted negatively and the existence of sex is denied. This may be due to the long and difficult history of gender studies in natural sciences. For a long time, pseudoscientific misinterpretations of results of gender studies were used to manifest the inferior social position of women. However, since more than thirty years respectable gender studies are integrated in social as well as natural sciences. Gender studies are integrative parts of nearly all subdisciplines of biological anthropology. The formation of a working group for gender studies within the GfA seems therefore to be useful.
Shen, Chao-Yu; Tyan, Yeu-Sheng; Kuo, Li-Wei; Wu, Changwei W; Weng, Jun-Cheng
2015-01-01
Radiation therapy is widely used for the treatment of brain tumors and may result in cellular, vascular and axonal injury and further behavioral deficits. The non-invasive longitudinal imaging assessment of brain injury caused by radiation therapy is important for determining patient prognoses. Several rodent studies have been performed using magnetic resonance imaging (MRI), but further studies in rabbits and large mammals with advanced magnetic resonance (MR) techniques are needed. Previously, we used diffusion tensor imaging (DTI) to evaluate radiation-induced rabbit brain injury. However, DTI is unable to resolve the complicated neural structure changes that are frequently observed during brain injury after radiation exposure. Generalized q-sampling imaging (GQI) is a more accurate and sophisticated diffusion MR approach that can extract additional information about the altered diffusion environments. Therefore, herein, a longitudinal study was performed that used GQI indices, including generalized fractional anisotropy (GFA), quantitative anisotropy (QA), and the isotropic value (ISO) of the orientation distribution function and DTI indices, including fractional anisotropy (FA) and mean diffusivity (MD) over a period of approximately half a year to observe long-term, radiation-induced changes in the different brain compartments of a rabbit model after a hemi-brain single dose (30 Gy) radiation exposure. We revealed that in the external capsule, the GFA right to left (R/L) ratio showed similar trends as the FA R/L ratio, but no clear trends in the remaining three brain compartments. Both the QA and ISO R/L ratios showed similar trends in the all four different compartments during the acute to early delayed post-irradiation phase, which could be explained and reflected the histopathological changes of the complicated dynamic interactions among astrogliosis, demyelination and vasogenic edema. We suggest that GQI is a promising non-invasive technique and as compared with DTI, it has better potential ability in detecting and monitoring the pathophysiological cascades in acute to early delayed radiation-induced brain injury by using clinical MR scanners.
76 FR 35000 - Agency Information Collection Activities; Proposed Collection; Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-15
... violence or trauma in any setting (including community or school violence; domestic violence; physical...--Trauma and Violence and Military Families. The new items will be added to the Transformation... families, experiences with trauma, and experiences with violence GFA, there is a proposed new data...
NASA Technical Reports Server (NTRS)
Shevade, A. V.; Ryan, M. A.; Homer, M. L.; Jewell, A. D.; Zhou, H.; Manatt, K.; Kisor, A. K.
2005-01-01
We report a Quantitative Structure-Activity Relationships (QSAR) study using Genetic Function Approximations (GFA) to describe the polymer-carbon composite sensor activities in the JPL Electronic Nose, when exposed to chemical vapors at parts-per-million concentration levels.
Testing the Construct Validity of the Gambling Functional Assessment-Revised
ERIC Educational Resources Information Center
Weatherly, Jeffrey N.; Miller, Joseph C.; Terrell, Heather K.
2011-01-01
An attempt was made to modify the Gambling Functional Assessment (GFA), which was proposed to identify four possible contingencies maintaining the respondent's gambling behavior. However, previous research found that it only identified two contingencies (i.e., positive vs. negative reinforcement), with some items cross-loading on both…
76 FR 53913 - Agency Information Collection Activities: Submission for OMB Review; Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-30
.... Have you ever experienced violence or trauma in any setting (including community or school violence... instrument will allow SAMHSA to collect information on two new strategic initiatives--Trauma and Violence and... questions regarding military families, experiences with trauma, and experiences with violence GFA, there is...
76 FR 53916 - Agency Information Collection Activities: Submission for OMB Review; Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-30
... violence or trauma in any setting (including community or school violence; domestic violence; physical...--Trauma and Violence and Military Families. The new items will be added to the Transformation... families, experiences with trauma, and experiences with violence GFA, there is a proposed new data...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lan, Xiaodong; Wu, Hong, E-mail: wuhong927@126.com
Metallic glass composite coatings Ti{sub 45}Cu{sub 41}Ni{sub 9}Zr{sub 5} and Ti{sub 45}Cu{sub 41}Ni{sub 6}Zr{sub 5}Sn{sub 3} (at.%) on a Ti-30Nb-5Ta-7Zr (wt.%) (TNTZ) alloy were prepared by laser cladding. The microstructures of the coatings were characterized by means of X-ray diffractometry (XRD), scanning electron microscopy (SEM) equipped with energy dispersive X-ray analyzer (EDXA), and transmission electron microscopy (TEM). Results indicated that the coatings have an amorphous structure embedded with a few nanocrystalline phases and dendrites. A partial substitution of Ni by Sn can improve the glass forming ability of Ti-base metallic glass system, and induce the formation of nano-sized Ni{sub 2}SnTimore » phase during the cyclic laser heating. The tribological behavior of both the substrate and the coatings was investigated in detail. A significant improvement in both the hardness and the wear resistance of the coatings was achieved with the addition of Sn. The relationship between the wear resistance and the microstructures of the coatings was discussed. - Highlights: •Ti-based metallic glass composite coatings were prepared by laser cladding. •The wear resistance is greatly improved by laser cladding of composite coatings. •Substitution of Ni by Sn increases GFA and wear resistance of the coatings. •A good balance of crystalline/amorphous phases improves the wear resistance. •Adhesive wear serves as the dominant wear mechanism of the composite coatings.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Valdes, Haydee; Spiwok, Vojtech; Rezac, Jan
2008-04-17
The free-energy surface (FES) of glycyl-phenylalanyl-alanine (GFA) tripeptide was explored by molecular dynamics (MD) simulations in combination with high-level correlated ab initio quantum chemical calculations and metadynamics. Both the MD and metadynamics employed the tightbinding DFT-D method instead of the AMBER force field, which yielded inaccurate results. We classified the minima localised in the FESs as follows: a) the backbone-conformational arrangement; and b) the existence of a COOH---OC intramolecular H-bond (families CO₂Hfree and CO₂Hbonded). Comparison with experimental results showed that the most stable minima in the FES correspond to the experimentally observed structures. Remarkably, however, we did not observe experimentallymore » the CO₂Hbonded family (also predicted by metadynamics), although its stability is comparable to that of the CO₂Hfree structures. This fact was explained by the former’s short excited state lifetime. We also carried out ab initio calculations using DFT-D and the M06-2X functional. The importance of the dispersion energy in stabilizing peptide conformers is well reflected by our pioneer analysis using the DFT-SAPT method to explore the nature of the backbone/side-chain interactions.« less
Geomorphic Flood Area (GFA): a QGIS tool for a cost-effective delineation of the floodplains
NASA Astrophysics Data System (ADS)
Samela, Caterina; Albano, Raffaele; Sole, Aurelia; Manfreda, Salvatore
2017-04-01
The importance of delineating flood hazard and risk areas at a global scale has been highlighted for many years. However, its complete achievement regularly encounters practical difficulties, above all the lack of data and implementation costs. In conditions of scarce data availability (e.g. ungauged basins, large-scale analyses), a fast and cost-effective floodplain delineation can be carried out using geomorphic methods (e.g., Manfreda et al., 2011; 2014). In particular, an automatic DEM-based procedure has been implemented in an open-source QGIS plugin named Geomorphic Flood Area - tool (GFA - tool). This tool performs a linear binary classification based on the recently proposed Geomorphic Flood Index (GFI), which exhibited high classification accuracy and reliability in several test sites located in Europe, United States and Africa (Manfreda et al., 2015; Samela et al., 2016, 2017; Samela, 2016). The GFA - tool is designed to make available to all users the proposed procedure, that includes a number of operations requiring good geomorphic and GIS competences. It allows computing the GFI through terrain analysis, turning it into a binary classifier, and training it on the base of a standard inundation map derived for a portion of the river basin (a minimum of 2% of the river basin's area is suggested) using detailed methods of analysis (e.g. flood hazard maps produced by emergency management agencies or river basin authorities). Finally, GFA - tool allows to extend the classification outside the calibration area to delineate the flood-prone areas across the entire river basin. The full analysis has been implemented in this plugin with a user-friendly interface that should make it easy to all user to apply the approach and produce the desired results. Keywords: flood susceptibility; data scarce environments; geomorphic flood index; linear binary classification; Digital elevation models (DEMs). References Manfreda, S., Di Leo, M., Sole, A., (2011). Detection of Flood Prone Areas using Digital Elevation Models, Journal of Hydrologic Engineering, 16(10), 781-790. Manfreda, S., Nardi, F., Samela, C., Grimaldi, S., Taramasso, A. C., Roth, G., & Sole, A. (2014). Investigation on the Use of Geomorphic Approaches for the Delineation of Flood Prone Areas, Journal of Hydrology, 517, 863-876. Manfreda, S., Samela, C., Gioia, A., Consoli, G., Iacobellis, V., Giuzio, L., & Sole, A. (2015). Flood-prone areas assessment using linear binary classifiers based on flood maps obtained from 1D and 2D hydraulic models. Natural Hazards, Vol. 79 (2), pp 735-754. Samela, C. (2016), 100-year flood susceptibility maps for the continental U.S. derived with a geomorphic method. University of Basilicata. Dataset. Samela, C., Manfreda, S., Paola, F. D., Giugni, M., Sole, A., & Fiorentino, M. (2016). DEM-Based Approaches for the Delineation of Flood-Prone Areas in an Ungauged Basin in Africa. Journal of Hydrologic Engineering, 21(2), 1-10. Samela, C., Troy, T.J., Manfreda, S. (2017). Geomorphic classifiers for flood-prone areas delineation for data-scarce environments, Advances in Water Resources (under review).
Maganti, Lakshmi; Das, Sanjit Kumar; Mascarenhas, Nahren Manuel; Ghoshal, Nanda
2011-10-01
The re-emergence of tuberculosis infections, which are resistant to conventional drug therapy, has steadily risen in the last decade. Inhibitors of aryl acid adenylating enzyme known as MbtA, involved in siderophore biosynthesis in Mycobacterium tuberculosis, are being explored as potential antitubercular agents. The ability to identify fragments that interact with a biological target is a key step in fragment based drug design (FBDD). To expand the boundaries of quantitative structure activity relationship (QSAR) paradigm, we have proposed a Fragment Based QSAR methodology, referred here in as FB-QSAR, for deciphering the structural requirements of a series of nucleoside bisubstrate analogs for inhibition of MbtA, a key enzyme involved in siderophore biosynthetic pathway. For the development of FB-QSAR models, statistical techniques such as stepwise multiple linear regression (SMLR), genetic function approximation (GFA) and GFAspline were used. The predictive ability of the generated models was validated using different statistical metrics, and similarity-based coverage estimation was carried out to define applicability boundaries. To aid the creation of novel antituberculosis compounds, a bioisosteric database was enumerated using the combichem approach endorsed mining in a lead-like chemical space. The generated library was screened using an integrated in-silico approach and potential hits identified. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Recent advances in bulk metallic glasses for biomedical applications.
Li, H F; Zheng, Y F
2016-05-01
With a continuously increasing aging population and the improvement of living standards, large demands of biomaterials are expected for a long time to come. Further development of novel biomaterials, that are much safer and of much higher quality, in terms of both biomedical and mechanical properties, are therefore of great interest for both the research scientists and clinical surgeons. Compared with the conventional crystalline metallic counterparts, bulk metallic glasses have unique amorphous structures, and thus exhibit higher strength, lower Young's modulus, improved wear resistance, good fatigue endurance, and excellent corrosion resistance. For this purpose, bulk metallic glasses (BMGs) have recently attracted much attention for biomedical applications. This review discusses and summarizes the recent developments and advances of bulk metallic glasses, including Ti-based, Zr-based, Fe-based, Mg-based, Zn-based, Ca-based and Sr-based alloying systems for biomedical applications. Future research directions will move towards overcoming the brittleness, increasing the glass forming ability (GFA) thus obtaining corresponding bulk metallic glasses with larger sizes, removing/reducing toxic elements, and surface modifications. Bulk metallic glasses (BMGs), also known as amorphous alloys or liquid metals, are relative newcomers in the field of biomaterials. They have gained increasing attention during the past decades, as they exhibit an excellent combination of properties and processing capabilities desired for versatile biomedical implant applications. The present work reviewed the recent developments and advances of biomedical BMGs, including Ti-based, Zr-based, Fe-based, Mg-based, Zn-based, Ca-based and Sr-based BMG alloying systems. Besides, the critical analysis and in-depth discussion on the current status, challenge and future development of biomedical BMGs are included. The possible solution to the BMG size limitation, the brittleness of BMGs has been proposed. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Geomorphic Flood Area (GFA): a DEM-based tool for flood susceptibility mapping at large scales
NASA Astrophysics Data System (ADS)
Manfreda, S.; Samela, C.; Albano, R.; Sole, A.
2017-12-01
Flood hazard and risk mapping over large areas is a critical issue. Recently, many researchers are trying to achieve a global scale mapping encountering several difficulties, above all the lack of data and implementation costs. In data scarce environments, a preliminary and cost-effective floodplain delineation can be performed using geomorphic methods (e.g., Manfreda et al., 2014). We carried out several years of research on this topic, proposing a morphologic descriptor named Geomorphic Flood Index (GFI) (Samela et al., 2017) and developing a Digital Elevation Model (DEM)-based procedure able to identify flood susceptible areas. The procedure exhibited high accuracy in several test sites in Europe, United States and Africa (Manfreda et al., 2015; Samela et al., 2016, 2017) and has been recently implemented in a QGIS plugin named Geomorphic Flood Area (GFA) - tool. The tool allows to automatically compute the GFI, and turn it into a linear binary classifier capable of detecting flood-prone areas. To train this classifier, an inundation map derived using hydraulic models for a small portion of the basin is required (the minimum is 2% of the river basin's area). In this way, the GFA-tool allows to extend the classification of the flood-prone areas across the entire basin. We are also defining a simplified procedure for the estimation of the river depth, which may be helpful for large-scale analyses to approximatively evaluate the expected flood damages in the surrounding areas. ReferencesManfreda, S., Nardi, F., Samela, C., Grimaldi, S., Taramasso, A. C., Roth, G., & Sole, A. (2014). Investigation on the use of geomorphic approaches for the delineation of flood prone areas. J. Hydrol., 517, 863-876. Manfreda, S., Samela, C., Gioia, A., Consoli, G., Iacobellis, V., Giuzio, L., & Sole, A. (2016). Flood-prone areas assessment using linear binary classifiers based on flood maps obtained from 1D and 2D hydraulic models. Nat. Hazards, Vol. 79 (2), pp 735-754. Samela, C., Manfreda, S., Paola, F. D., Giugni, M., Sole, A., & Fiorentino, M. (2016). DEM-Based Approaches for the Delineation of Flood-Prone Areas in an Ungauged Basin in Africa. J. Hydrol. Eng,, 06015010. Samela, C., Troy, T. J., & Manfreda, S. (2017a). Geomorphic classifiers for flood-prone areas delineation for data-scarce environments. Adv. Water Resour., 102, 13-28.
Resolving Kirkuk: Lessons Learned from Settlements of Earlier Ethno-Territorial Conflicts
2012-01-01
interests, the Federation feared that the loss of Brčko would be seen as rewarding Serb-inflicted ethnic cleansing . The status of Brčko was thus a...governance arrangements for Mostar began with institutionalization of the status quo, which reflected ethnic cleansing during the war. The starting point...both made significant commitments that made the GFA palatable to both Unionists and Republicans. In Brčko, the international supervisor was given
Alloza, Clara; Cox, Simon R; Duff, Barbara; Semple, Scott I; Bastin, Mark E; Whalley, Heather C; Lawrie, Stephen M
2016-08-30
Several authors have proposed that schizophrenia is the result of impaired connectivity between specific brain regions rather than differences in local brain activity. White matter abnormalities have been suggested as the anatomical substrate for this dysconnectivity hypothesis. Information processing speed may act as a key cognitive resource facilitating higher order cognition by allowing multiple cognitive processes to be simultaneously available. However, there is a lack of established associations between these variables in schizophrenia. We hypothesised that the relationship between white matter and general intelligence would be mediated by processing speed. White matter water diffusion parameters were studied using Tract-based Spatial Statistics and computed within 46 regions-of-interest (ROI). Principal component analysis was conducted on these white matter ROI for fractional anisotropy (FA) and mean diffusivity, and on neurocognitive subtests to extract general factors of white mater structure (gFA, gMD), general intelligence (g) and processing speed (gspeed). There was a positive correlation between g and gFA (r= 0.67, p =0.001) that was partially and significantly mediated by gspeed (56.22% CI: 0.10-0.62). These findings suggest a plausible model of structure-function relations in schizophrenia, whereby white matter structure may provide a neuroanatomical substrate for general intelligence, which is partly supported by speed of information processing. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Shevade, Abhijit V.; Ryan, Margaret A.; Homer, Margie L.; Zhou, Hanying; Manfreda, Allison M.; Lara, Liana M.; Yen, Shiao-Pin S.; Jewell, April D.; Manatt, Kenneth S.; Kisor, Adam K.
We have developed a Quantitative Structure-Activity Relationships (QSAR) based approach to correlate the response of chemical sensors in an array with molecular descriptors. A novel molecular descriptor set has been developed; this set combines descriptors of sensing film-analyte interactions, representing sensor response, with a basic analyte descriptor set commonly used in QSAR studies. The descriptors are obtained using a combination of molecular modeling tools and empirical and semi-empirical Quantitative Structure-Property Relationships (QSPR) methods. The sensors under investigation are polymer-carbon sensing films which have been exposed to analyte vapors at parts-per-million (ppm) concentrations; response is measured as change in film resistance. Statistically validated QSAR models have been developed using Genetic Function Approximations (GFA) for a sensor array for a given training data set. The applicability of the sensor response models has been tested by using it to predict the sensor activities for test analytes not considered in the training set for the model development. The validated QSAR sensor response models show good predictive ability. The QSAR approach is a promising computational tool for sensing materials evaluation and selection. It can also be used to predict response of an existing sensing film to new target analytes.
Multi-Shell Hybrid Diffusion Imaging (HYDI) at 7 Tesla in TgF344-AD Transgenic Alzheimer Rats.
Daianu, Madelaine; Jacobs, Russell E; Weitz, Tara M; Town, Terrence C; Thompson, Paul M
2015-01-01
Diffusion weighted imaging (DWI) is widely used to study microstructural characteristics of the brain. Diffusion tensor imaging (DTI) and high-angular resolution imaging (HARDI) are frequently used in radiology and neuroscience research but can be limited in describing the signal behavior in composite nerve fiber structures. Here, we developed and assessed the benefit of a comprehensive diffusion encoding scheme, known as hybrid diffusion imaging (HYDI), composed of 300 DWI volumes acquired at 7-Tesla with diffusion weightings at b = 1000, 3000, 4000, 8000 and 12000 s/mm2 and applied it in transgenic Alzheimer rats (line TgF344-AD) that model the full clinico-pathological spectrum of the human disease. We studied and visualized the effects of the multiple concentric "shells" when computing three distinct anisotropy maps-fractional anisotropy (FA), generalized fractional anisotropy (GFA) and normalized quantitative anisotropy (NQA). We tested the added value of the multi-shell q-space sampling scheme, when reconstructing neural pathways using mathematical frameworks from DTI and q-ball imaging (QBI). We show a range of properties of HYDI, including lower apparent anisotropy when using high b-value shells in DTI-based reconstructions, and increases in apparent anisotropy in QBI-based reconstructions. Regardless of the reconstruction scheme, HYDI improves FA-, GFA- and NQA-aided tractography. HYDI may be valuable in human connectome projects and clinical research, as well as magnetic resonance research in experimental animals.
Multi-Shell Hybrid Diffusion Imaging (HYDI) at 7 Tesla in TgF344-AD Transgenic Alzheimer Rats
Daianu, Madelaine; Jacobs, Russell E.; Weitz, Tara M.; Town, Terrence C.; Thompson, Paul M.
2015-01-01
Diffusion weighted imaging (DWI) is widely used to study microstructural characteristics of the brain. Diffusion tensor imaging (DTI) and high-angular resolution imaging (HARDI) are frequently used in radiology and neuroscience research but can be limited in describing the signal behavior in composite nerve fiber structures. Here, we developed and assessed the benefit of a comprehensive diffusion encoding scheme, known as hybrid diffusion imaging (HYDI), composed of 300 DWI volumes acquired at 7-Tesla with diffusion weightings at b = 1000, 3000, 4000, 8000 and 12000 s/mm2 and applied it in transgenic Alzheimer rats (line TgF344-AD) that model the full clinico-pathological spectrum of the human disease. We studied and visualized the effects of the multiple concentric “shells” when computing three distinct anisotropy maps–fractional anisotropy (FA), generalized fractional anisotropy (GFA) and normalized quantitative anisotropy (NQA). We tested the added value of the multi-shell q-space sampling scheme, when reconstructing neural pathways using mathematical frameworks from DTI and q-ball imaging (QBI). We show a range of properties of HYDI, including lower apparent anisotropy when using high b-value shells in DTI-based reconstructions, and increases in apparent anisotropy in QBI-based reconstructions. Regardless of the reconstruction scheme, HYDI improves FA-, GFA- and NQA-aided tractography. HYDI may be valuable in human connectome projects and clinical research, as well as magnetic resonance research in experimental animals. PMID:26683657
ATE/ICEPM Development Report and Function Demonstration Test.
1975-01-01
DTfC JANUARY 1975 S U gl CONTRACT NO. DAAE07-73-C-0268 F - - -- - - b,,-4, i .y TRW SYSTEMS GROUP D - PROPULSION SYSTEMS LABORATORY t 82 07 22 067 II i ...DEMONSTRATION TEST FINAL REPORT Contract No. DAAEO7-73--C-0268 XccessiOf Yor U~ ultis. GFA& I copy~ t e!A C3 PY;E lilannoQ*C~INSPECTED otIo - Prepared by Bye...program L o Improvement of system hardware I o Preparation of systems support material 2.1 Development of the Diagnostic Engineering Structure The
Deformation of Extruded Titanium Alloys Under Superplastic Conditions
1988-07-01
176mm wide with a flange wall 37mm high x 27mm wide and a central web 122mm wide x 18mm thick. Round-bar test pieces aligned parallel to the principal...directions L, T and ST were extrac- ted from the flange and web as shown in Fig 1; gauge length dimensions were 15mm x 5.5mm diameter for the FST test...ares. in the gauge length. Flange Web X 9 NTIS GFA&I v FL Distribut I oc / A es ’- n:ia or Fig I Position of test pieces in extruded section iste i
Sathishkumar, Yesupatham; Velmurugan, Natarajan; Lee, Hyun Mi; Rajagopal, Kalyanaraman; Im, Chan Ki; Lee, Yang Soo
2014-08-01
Phenotypic and genotypic changes in Aspergillus niger and Penicillium chrysogenum, spore forming filamentous fungi, with respect to central chitin metabolism were studied under low shear modeled microgravity, normal gravity and static conditions. Low shear modeled microgravity (LSMMG) response showed a similar spore germination rate with normal gravity and static conditions. Interestingly, high ratio of multiple germ tube formation of A. niger in LSMMG condition was observed. Confocal laser scanning microscopy images of calcofluor flurophore stained A. niger and P. chrysogenum showed no significant variations between different conditions tested. Transmission electron microscopy images revealed number of mitochondria increased in P. chrysogenum in low shear modeled microgravity condition but no stress related-woronin bodies in fungal hyphae were observed. To gain additional insight into the cell wall integrity under different conditions, transcription level of a key gene involved in cell wall integrity gfaA, encoding the glutamine: fructose-6-phosphate amidotransferase enzyme, was evaluated using qRT-PCR. The transcription level showed no variation among different conditions. Overall, the results collectively indicate that the LSMMG has shown no significant stress on spore germination, mycelial growth, cell wall integrity of potentially pathogenic fungi, A. niger and P. chrysogenum.
Mirkhani, Seyyed Alireza; Gharagheizi, Farhad; Sattari, Mehdi
2012-03-01
Evaluation of diffusion coefficients of pure compounds in air is of great interest for many diverse industrial and air quality control applications. In this communication, a QSPR method is applied to predict the molecular diffusivity of chemical compounds in air at 298.15K and atmospheric pressure. Four thousand five hundred and seventy nine organic compounds from broad spectrum of chemical families have been investigated to propose a comprehensive and predictive model. The final model is derived by Genetic Function Approximation (GFA) and contains five descriptors. Using this dedicated model, we obtain satisfactory results quantified by the following statistical results: Squared Correlation Coefficient=0.9723, Standard Deviation Error=0.003 and Average Absolute Relative Deviation=0.3% for the predicted properties from existing experimental values. Copyright © 2011 Elsevier Ltd. All rights reserved.
Wu, Wensheng; Zhang, Canyang; Lin, Wenjing; Chen, Quan; Guo, Xindong; Qian, Yu; Zhang, Lijuan
2015-01-01
Self-assembled nano-micelles of amphiphilic polymers represent a novel anticancer drug delivery system. However, their full clinical utilization remains challenging because the quantitative structure-property relationship (QSPR) between the polymer structure and the efficacy of micelles as a drug carrier is poorly understood. Here, we developed a series of QSPR models to account for the drug loading capacity of polymeric micelles using the genetic function approximation (GFA) algorithm. These models were further evaluated by internal and external validation and a Y-randomization test in terms of stability and generalization, yielding an optimization model that is applicable to an expanded materials regime. As confirmed by experimental data, the relationship between microstructure and drug loading capacity can be well-simulated, suggesting that our models are readily applicable to the quantitative evaluation of the drug-loading capacity of polymeric micelles. Our work may offer a pathway to the design of formulation experiments.
Lin, Wenjing; Chen, Quan; Guo, Xindong; Qian, Yu; Zhang, Lijuan
2015-01-01
Self-assembled nano-micelles of amphiphilic polymers represent a novel anticancer drug delivery system. However, their full clinical utilization remains challenging because the quantitative structure-property relationship (QSPR) between the polymer structure and the efficacy of micelles as a drug carrier is poorly understood. Here, we developed a series of QSPR models to account for the drug loading capacity of polymeric micelles using the genetic function approximation (GFA) algorithm. These models were further evaluated by internal and external validation and a Y-randomization test in terms of stability and generalization, yielding an optimization model that is applicable to an expanded materials regime. As confirmed by experimental data, the relationship between microstructure and drug loading capacity can be well-simulated, suggesting that our models are readily applicable to the quantitative evaluation of the drug-loading capacity of polymeric micelles. Our work may offer a pathway to the design of formulation experiments. PMID:25780923
[Aerobic methylobacteria as the basis for a biosensor for dichloromethane detection].
Plekhanova, Iu V; Firsova, Iu E; Doronina, N V; Trotsenko, Iu A; Reshetilov, A N
2013-01-01
Cells of dichloromethane (DChM) bacteria-destructors were immobilized by sorption on different types of membranes, which were fixed on the measuring surface of a pH-sensitive field transistor. The presence of DChM in the medium (0.6-8.8 mM) led to a change in the transistor's output signal, which was determined by the appearance of H+ ions in the medium due to DChM utilization by methylobateria. Among four strains of methylobacteria--Methylobacterium dichloromethanicum DM4, Methylobacterium extorquens DM 17, Methylopila helvetica DM6, and Ancylobacter dichloromethanicus DM 16--the highest and most stable activity toward DChM degradation was observed in the strain M. dichloromethanicum DM4. Among 11 types of membranes for cell immobilization, Millipore nitrocellulose membranes and chromatographic fiber paper GF/A, which allow one to obtain stable biosensor signals for 2 weeks without a bioreceptor change, were chosen as optimal carriers.
Improved Controller Design of Grid Friendly™ Appliances for Primary Frequency Response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lian, Jianming; Sun, Yannan; Marinovici, Laurentiu D.
2015-09-01
The Grid Friendlymore » $$^\\textrm{TM}$$ Appliance~(GFA) controller, developed at Pacific Northwest National Laboratory, can autonomously switch off the appliances by detecting the under-frequency events. In this paper, the impacts of curtailing frequency threshold on the performance of frequency responsive GFAs are carefully analyzed first. The current method of selecting curtailing frequency thresholds for GFAs is found to be insufficient to guarantee the desired performance especially when the frequency deviation is shallow. In addition, the power reduction of online GFAs could be so excessive that it can even impact the system response negatively. As a remedy to the deficiency of the current controller design, a different way of selecting curtailing frequency thresholds is proposed to ensure the effectiveness of GFAs in frequency protection. Moreover, it is also proposed to introduce a supervisor at each distribution feeder to monitor the curtailing frequency thresholds of online GFAs and take corrective actions if necessary.« less
Simmons, Teisha M; Novins, Douglas K; Allen, James
2004-08-12
Circles of Care grantees were provided the opportunity to develop a locally relevant definition of serious emotional disturbance that would be used to define what type of emotional, behavioral, and mental disability would be required to receive services. After conducting detailed assessments of the definition in the guidance for applicants GFA and the definitions used by others in their respective states, seven of the nine grantees developed their own local, project-specific definitions through the participation of community focus groups and Advisory Councils. The six definitions for SED developed by rural grantees all included American Indian and Alaska Native concepts specific to each tribal community's culture; the urban grantee's definition was purposely focused for reaching out to non-professional members of the community. This opportunity for the communities to redefine SED not only provided each community with a definition which would be more culturally specific, but also proved to be an extraordinarily exercise in empowerment and self-determination.
Wang, Zhengjian; Banks, Charles
2006-10-01
The research examines the potential for bio-clogging in filter packs containing fine sand of the type typically used in extraction wells for pumping leachates containing fine particulate matter, such as cement kiln dust (CKD). Three filter media with different particle sizes were used: 1.7-4.75, 0.35-1.0, and 0.235-0.45 mm. Each sand filter was tested using a leachate recirculating column reactor with a free drainage layer, on top of which was placed the filtration medium which was kept saturated and at a positive hydrostatic head by a 2-l reservoir of leachate. The leachate was collected from a landfill site that had been used for the co-disposal of municipal solid waste (MSW) and CKD. The leachate used was filtered by passing through a Whatman GFA filter paper before being added to the reactors in order to eliminate as far as possible the non-biological clogging which might have resulted from the introduction of particulate matter in the form of CKD. The filters and a control experiment were run under anaerobic conditions at 35 degrees C. The bio-clogging potential was observed by taking differential manometer readings from manometers located in the drainage and reservoir sections of the reactor. No clogging was detected using the coarser of the filter media, but there was some clogging when a finer filter medium was used. Head space gas analysis indicated that methanogenic activity was inhibited and analysis of the liquid phase indicated that the microbial process responsible for removal of chemical oxygen demand (COD) was principally one of sulphate reduction.
Glass Forming Ability in Systems with Competing Orderings
NASA Astrophysics Data System (ADS)
Russo, John; Romano, Flavio; Tanaka, Hajime
2018-04-01
Some liquids, if cooled rapidly enough to avoid crystallization, can be frozen into a nonergodic glassy state. The tendency for a material to form a glass when quenched is called "glass-forming ability," and it is of key significance both fundamentally and for materials science applications. Here, we consider liquids with competing orderings, where an increase in the glass-forming ability is signaled by a depression of the melting temperature towards its minimum at triple or eutectic points. With simulations of two model systems where glass-forming ability can be tuned by an external parameter, we are able to interpolate between crystal-forming and glass-forming behavior. We find that the enhancement of the glass-forming ability is caused by an increase in the structural difference between liquid and crystal: stronger competition in orderings towards the melting point minimum makes a liquid structure more disordered (more complex). This increase in the liquid-crystal structure difference can be described by a single adimensional parameter, i.e., the interface energy cost scaled by the thermal energy, which we call the "thermodynamic interface penalty." Our finding may provide a general physical principle for not only controlling the glass-forming ability but also the emergence of glassy behavior of various systems with competing orderings, including orderings of structural, magnetic, electronic, charge, and dipolar origin.
NASA Astrophysics Data System (ADS)
Bazlov, A. I.; Tsarkov, A. A.; Ketov, S. V.; Suryanarayana, C.; Louzguine-Luzgin, D. V.
2018-02-01
Effect of multiple alloying elements on the glass-forming ability, thermal stability, and crystallization behavior of Zr-based glass-forming alloys were studied in the present work. We investigated the effect of complete or partial substitution of Ti and Ni with similar early and late transition metals, respectively, on the glass-forming ability and crystallization behavior of the Zr50Ti10Cu20Ni10Al10 alloy. Poor correlation was observed between different parameters indicating the glass-forming ability and the critical size of the obtained glassy samples. Importance of the width of the crystallization interval is emphasized. The kinetics of primary crystallization, i.e., the rate of nucleation and rate of growth of the nuclei of primary crystals is very different from that of the eutectic alloys. Thus, it is difficult to estimate the glass-forming ability only on the basis of the empirical parameters not taking into account the crystallization behavior and the crystallization interval.
Blaabjerg, Lasse I; Lindenberg, Eleanor; Löbmann, Korbinian; Grohganz, Holger; Rades, Thomas
2016-09-06
The aim of this study was to investigate the glass forming ability of 12 different drugs by the determination of continuous cooling and isothermal transformation diagrams in order to elucidate if an inherent differentiation between the drugs with respect to their the glass forming ability can be made. Continuous-cooling-transformation (CCT) and time-temperature-transformation (TTT) diagrams of the drugs were developed in order to predict the critical cooling rate necessary to convert the drug from the melt into an amorphous form. While TTT diagrams overestimated the actual critical cooling rate, they allowed an inherent differentiation of glass forming ability for the investigated drugs into drugs that are extremely difficult to amorphize (>750 °C/min), drugs that require modest cooling rates (>10 °C/min), and drugs that can be made amorphous even at very slow cooling rates (>2 °C/min). Thus, the glass forming ability can be predicted by the use of TTT diagrams. In contrast to TTT diagrams, CCT diagrams may not be suitable for small organic molecules due to poor separation of exothermic events, which makes it difficult to determine the zone of recrystallization. In conclusion, this study shows that glass forming ability of drugs can be predicted by TTT diagrams.
ERIC Educational Resources Information Center
Giessman, Jacob A.; Gambrell, James L.; Stebbins, Molly S.
2013-01-01
The Naglieri Nonverbal Ability Test, Second Edition (NNAT2), is used widely to screen students for possible inclusion in talent development programs. The NNAT2 claims to provide a more culturally neutral evaluation of general ability than tests such as Form 6 of the Cognitive Abilities Test (CogAT6), which has Verbal and Quantitative batteries in…
The effect of rearing environment on memory formation.
Rothwell, Cailin M; Spencer, Gaynor E; Lukowiak, Ken
2018-05-22
Lymnaea stagnalis is a well-studied model system for determining how changes in the environment influence associative learning and memory formation. For example, some wild strains of L. stagnalis , collected from separate geographic locations, show superior memory-forming abilities compared with others. Here, we studied memory formation in two laboratory-bred L. stagnalis strains, derived from the same original population in The Netherlands. The two strains were reared in two different laboratories at the University of Calgary (C-strain) and at Brock University (B-strain) for many years and we found that they differed in their memory-forming ability. Specifically, the C-strain required only two training sessions to form long-term memory (LTM) whereas the B-strain required four sessions to form LTM. Additionally, the LTM formed by the B-strain persisted for a shorter amount of time than the memory formed by the C-strain. Thus, despite being derived from the same original population, the C- and B-strains have developed different memory-forming abilities. Next, we raised the two strains from embryos away from home (i.e. in the other laboratory) over two generations and assessed their memory-forming abilities. The B-strain reared and maintained at the University of Calgary demonstrated improved memory-forming ability within a single generation, while the C-strain reared at Brock University retained their normal LTM-forming ability across two subsequent generations. This suggests that local environmental factors may contribute to the behavioural divergence observed between these two laboratory-bred strains. © 2018. Published by The Company of Biologists Ltd.
Dincer, U Deniz
2016-05-30
Endothelium represents a defense barrier and responds and integrates neuro humoral stimulus which describes as a compensatory mechanism. Endothelium formed with endothelial cells (ECs) and their progenitors. Endothelial progenitor cells (EPCs) represent minor subpopulation of mononuclear cells in the blood. During acute hypoxia, larger amount of EPCs mobilize into the peripheral blood and they directly contribute revascularization process. One of the subtypes of EPC is termed endothelial colony forming cells (ECFCs) which they possess de novo vessel-forming ability. The present study aims to investigate the role of hypoxia in EPCs functional and vessel-forming ability. Furthermore, it was investigated whether fetal exposure to a diabetic intrauterine environment influence EPCs adaptation ability. Human umbilical cord blood (HUCB) derived ECFCs were selected in all experimental procedures obtained from normal and gestational diabetes mellitus (GDM) subjects via in vitro cell culture methods. Early passage (<5) HUCB ECFCs obtain from GDM (n; 5) and control (n; 5) subjects were cultured with plates pre-coated with collagen in vitro 72 h hypoxic as well as normoxic condition. Endothelial, angiogenic and hypoxia associated gene specific primers designed to perform Real-time PCR. Senescenes assay conducted onto HUCB ECFCs to investigate their functional clonogenic ability. To quantify their vessel forming ability matrigel assay was applied. These data demonstrates that moderate hypoxia results increased vessel-forming ability and VEGFA expression in HUCB ECFCs obtained from control subjects. However, GDM caused to impede compensatory defense reaction against hypoxia which observed in control subjects. Thus, it illuminates beneficial information related future therapeutic modalities.
NASA Astrophysics Data System (ADS)
Nirawati, R.
2018-04-01
This research was conducted to see whether the variation of the solution is acceptable and easy to understand by students with different level of ability so that it can be seen the difference of students ability in facilitating the quadratic form in the upper, middle and lower groups. This research used experimental method with factorial design. Based on the result of final test analysis, there were differences of students ability in upper group, medium group, and lower group in putting squared form based on the use certain variation of solution.
Conus, Philippe; Fournier, Margot; Xin, Lijing; Cleusix, Martine; Baumann, Philipp S; Ferrari, Carina; Cousins, Ann; Alameda, Luis; Gholam-Razaee, Mehdi; Golay, Philippe; Jenni, Raoul; Woo, Tsung-Ung Wilson; Keshavan, Matcheri; Eap, Chin B; Wojcik, Joanne; Cuenod, Michel; Buclin, Thierry; Gruetter, Rolf; Seidman, Larry; Do, Kim
2018-01-01
Abstract Background Oxidative stress, coupled with dysregulation of inflammation, NMDAR and dopamine, is involved in schizophrenia (SZ) pathophysiology. Earlier add-on clinical trials showed in chronic SZ patients that NAC, a precursor of glutathione (GSH), an important cerebral antioxidant, improved negative symptoms, mismatch negativity and local synchronization. We hypothesized that NAC at an earlier stage of illness would have a greater impact. Methods Early psychosis patients (EP, less than 5 years of illness, N=63; NAC=32, placebo=31) were supplemented with NAC (2.7g/day, 6 months) in a double-blind randomized placebo-controlled trial. Outcome measures: PANSS and neurocognition (MATRICS Consensus Cognitive Battery; n=36); quantification of medial prefronfal cortex glutathione (GSHmPFC) by 1H-magnetic-resonance-spectroscopy, of white matter diffusion properties estimated by generalized fractional anisotropy (gFA) computed from diffusion spectrum imaging (DSI), of blood cells GSH (GSHBC) and GSH peroxidase activity (GPxBC) at start and end of trial Results While PANSS negative and positive were not affected by NAC, NAC improved Processing Speed (NAC > Placebo; F(1, 30)=5.849, p=.022), favoring 2 of 3 processing speed tasks (Trail Making A, F(1, 30)=4.279, p=.048 & Verbal Fluency, F(1, 30)=5.749, p=.023). GSHmPFC (+23%, p=0.005) and GSHBC (+19%, p=0.05) were increased following NAC treatment. In patients with high-baseline GPxBC (>22.3U/gHb), subgroup explorations revealed an improvement of PANSS positive compared to placebo (p=0.02). The change of PANSS positive correlated negatively with that of GPxBC activity, showing that the improvement paralleled the restoration of redox status. NAC group showed 11% increase in fornix white matter integrity as measured by gFA, correlating with an increase in GSHmPFC over the 6-months period. Discussion This is the first clinical trial assessing the impact of NAC treatment in a sample of EP and the potential predictive role of peripheral biomarkers of redox dysregulation. The hypothesis that NAC would be beneficial to negative symptoms in EP was not confirmed in this small sample, most likely in reason of their very low level at baseline. The NAC induced GSHmPFC increase demonstrates its target engagement. NAC improved Processing Speed showing a therapeutic enhancement of cognitive functions. Most importantly, NAC improved fornix integrity, in association with brain GSH elevation, demonstrating for the first time that a redox regulator can enhance structural connectivity. Peripheral redox status allows identifying a subgroup of patients with improved positive symptoms. Future biomarker guided antioxidant interventions in larger EP samples should replicate these findings.
[Apatite-forming ability of pure titanium implant after micro-arc oxidation treatment].
Tian, Zhihui; Zhang, Yu; Wang, Lichao; Nan, Kaihui
2013-10-01
To investigate the apatite forming ability of pure titanium implant after micro-arc oxidation treatment in simulated body fluid (SBF) and obtain implants with calcium phosphate (Ca-P) layers. The implants were immersed in (SBF) after micro-arc oxidation treatment for different time lengths, and their apatite forming ability and the morphology and constituents of the Ca-P layers formed on the sample surface were analyzed using X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and energy dispersive electron probe. After immersion in SBF, large quantities of Ca-P layers were induced on the surface of the samples. The Ca-P layers were composed of octacalcium phosphate and carbonated hydroxyapatite, and the crystals showed a plate-like morphology with an oriented growth. The implants with micro-arc oxidation treatment show good apatite forming ability on the surface with rich calcium and phosphorus elements. The formed layers are composed of bone-like apatite including octacalcium phosphate and carbonated hydroxyapatite.
ERIC Educational Resources Information Center
van Vianen, Annelies E. M.; Klehe, Ute-Christine; Koen, Jessie; Dries, Nicky
2012-01-01
The Career Adapt-Abilities Scale (CAAS)--Netherlands Form consists of four scales, each with six items, which measure concern, control, curiosity, and confidence as psychosocial resources for managing occupational transitions, developmental tasks, and work traumas. Internal consistency estimates for the subscale and total scores ranged from…
ERIC Educational Resources Information Center
Soresi, Salvatore; Nota, Laura; Ferrari, Lea
2012-01-01
The Career Adapt-Abilities Scale (CAAS)-Italian Form consists of four 6-item scales, which measure concern, control, curiosity, and confidence as psychosocial resources for managing occupational transitions, developmental tasks, and work traumas. The 24-item CAAS-Italian Form is identical to the International Form 2.0. The factor structure was…
Bone regeneration performance of surface-treated porous titanium.
Amin Yavari, Saber; van der Stok, Johan; Chai, Yoke Chin; Wauthle, Ruben; Tahmasebi Birgani, Zeinab; Habibovic, Pamela; Mulier, Michiel; Schrooten, Jan; Weinans, Harrie; Zadpoor, Amir Abbas
2014-08-01
The large surface area of highly porous titanium structures produced by additive manufacturing can be modified using biofunctionalizing surface treatments to improve the bone regeneration performance of these otherwise bioinert biomaterials. In this longitudinal study, we applied and compared three types of biofunctionalizing surface treatments, namely acid-alkali (AcAl), alkali-acid-heat treatment (AlAcH), and anodizing-heat treatment (AnH). The effects of treatments on apatite forming ability, cell attachment, cell proliferation, osteogenic gene expression, bone regeneration, biomechanical stability, and bone-biomaterial contact were evaluated using apatite forming ability test, cell culture assays, and animal experiments. It was found that AcAl and AnH work through completely different routes. While AcAl improved the apatite forming ability of as-manufactured (AsM) specimens, it did not have any positive effect on cell attachment, cell proliferation, and osteogenic gene expression. In contrast, AnH did not improve the apatite forming ability of AsM specimens but showed significantly better cell attachment, cell proliferation, and expression of osteogenic markers. The performance of AlAcH in terms of apatite forming ability and cell response was in between both extremes of AnH and AsM. AcAl resulted in significantly larger volumes of newly formed bone within the pores of the scaffold as compared to AnH. Interestingly, larger volumes of regenerated bone did not translate into improved biomechanical stability as AnH exhibited significantly better biomechanical stability as compared to AcAl suggesting that the beneficial effects of cell-nanotopography modulations somehow surpassed the benefits of improved apatite forming ability. In conclusion, the applied surface treatments have considerable effects on apatite forming ability, cell attachment, cell proliferation, and bone ingrowth of the studied biomaterials. The relationship between these properties and the bone-implant biomechanics is, however, not trivial. Copyright © 2014 Elsevier Ltd. All rights reserved.
Career Adapt-Abilities Scale--China Form: Construction and Initial Validation
ERIC Educational Resources Information Center
Hou, Zhi-Jin; Leung, S. Alvin; Li, Xixi; Li, Xu; Xu, Hui
2012-01-01
The Career Adapt-Abilities Scale (CAAS)--China Form consists of four subscales, with six items each to measure Concern, Control, Curiosity, and Confidence as psychosocial resources for managing occupational transitions, developmental tasks, and work traumas. This study investigated the construction and validation of its Chinese Form. Results…
The Relationship between Form and Function Level Receptive Prosodic Abilities in Autism
ERIC Educational Resources Information Center
Jarvinen-Pasley, Anna; Peppe, Susan; King-Smith, Gavin; Heaton, Pamela
2008-01-01
Prosody can be conceived as having form (auditory-perceptual characteristics) and function (pragmatic/linguistic meaning). No known studies have examined the relationship between form- and function-level prosodic skills in relation to the effects of stimulus length and/or complexity upon such abilities in autism. Research in this area is both…
Career Adapt-Abilities Scale--Taiwan Form: Psychometric Properties and Construct Validity
ERIC Educational Resources Information Center
Tien, Hsiu-Lan Shelley; Wang, Yu-Chen; Chu, Hui-Chuang; Huang, Tsu-Lun
2012-01-01
The present study tested the reliability and validity of the Career Adapt-Ability Scale--Taiwan Form (CAAS-Taiwan Form). The CAAS consists of four scales, each with six items, which measure concern, control, curiosity, and confidence as psychosocial resources for managing occupational transitions, developmental tasks, and work traumas. Internal…
Cloze Listening Test (Form Lisbon and Form Waco).
ERIC Educational Resources Information Center
Bowdidge, John S.
Designed to measure recall of specific information, ability to grasp the thought of a passage as a whole, and ability to apply various contextual clues while listening to a passage of aural communication, each of the alternate forms of the cloze listening test consists of an audio tape recording of approximately twenty minutes duration and a…
ERIC Educational Resources Information Center
Swanson, Jennifer R.; Bradley-Johnson, Sharon; Johnson, C. Merle; O'Dell, Anna Rubenaker
2009-01-01
Three studies examine the validity of the Preschool Form of the Cognitive Abilities Scale--Second Edition (CAS-2). Significant high concurrent criterion-related validity correlations, corrected for restricted range, are found between the CAS-2 and the Detroit Test of Learning Ability--Primary: Third Edition for 26 three-year-olds (r[subscript c] =…
TEM and Gravity Data for Roosevelt Hot Springs, Utah FORGE Site
Hardwick, Christian; Nash, Greg
2018-02-05
This submission includes a gravity data in text format and as a GIS point shapefile and transient electromagnetic (TEM) raw data. Each text file additionally contains location data (UTM Zone 12, NAD83) and elevation (meters) data for that station. The gravity data shapefile was in part downloaded from PACES, University of Texas at El Paso, http://gis.utep.edu/subpages/GMData.html, and in part collected by the Utah Geological Survey (UGS) as part of the DOE GTO supported Utah FORGE geothermal energy project near Milford, Utah. The PACES data were examined and scrubbed to eliminate any questionable data. A 2.67 g/cm^3 reduction density was used for the Bouguer correction. The attribute table column headers for the gravity data shapefile are explained below. There is also metadata attached to the GIS shapefile. name: the individual gravity station name. HAE: height above ellipsoid [meter] NGVD29: vertical datum for geoid [meter] obs: observed gravity ERRG: gravity measurement error [mGal] IZTC: inner zone terrain correction [mGal] OZTC: outer zone terrain correction [mGal] Gfa: free air gravity gSBGA: Bouguer horizontal slab sCBGA: Complete Bouguer anomaly
Development of an automated energy audit protocol for office buildings
NASA Astrophysics Data System (ADS)
Deb, Chirag
This study aims to enhance the building energy audit process, and bring about reduction in time and cost requirements in the conduction of a full physical audit. For this, a total of 5 Energy Service Companies in Singapore have collaborated and provided energy audit reports for 62 office buildings. Several statistical techniques are adopted to analyse these reports. These techniques comprise cluster analysis and development of prediction models to predict energy savings for buildings. The cluster analysis shows that there are 3 clusters of buildings experiencing different levels of energy savings. To understand the effect of building variables on the change in EUI, a robust iterative process for selecting the appropriate variables is developed. The results show that the 4 variables of GFA, non-air-conditioning energy consumption, average chiller plant efficiency and installed capacity of chillers should be taken for clustering. This analysis is extended to the development of prediction models using linear regression and artificial neural networks (ANN). An exhaustive variable selection algorithm is developed to select the input variables for the two energy saving prediction models. The results show that the ANN prediction model can predict the energy saving potential of a given building with an accuracy of +/-14.8%.
Yang, Ran; Yu, Lanlan; Zeng, Huajin; Liang, Ruiling; Chen, Xiaolan; Qu, Lingbo
2012-11-01
In this work, the interactions of twelve structurally different flavonoids with Lysozyme (Lys) were studied by fluorescence quenching method. The interaction mechanism and binding properties were investigated. It was found that the binding capacities of flavonoids to Lys were highly depend on the number and position of hydrogen, the kind and position of glycosyl. To explore the selectivity of the bindings of flavonoids with Lys, the structure descriptors of the flavonoids were calculated under QSAR software package of Cerius2, the quantitative relationship between the structures of flavonoids and their binding activities to Lys (QSAR) was performed through genetic function approximation (GFA) regression analysis. The QSAR regression equation was K(A) = 37850.460 + 1630.01Dipole +3038.330HD-171.795MR. (r = 0.858, r(CV)(2) = 0.444, F((11,3)) = 7.48), where K(A) is binding constants, Dipole, HD and MR was dipole moment, number of hydrogen-bond donor and molecular refractivity, respectively. The obtained results make us understand better how the molecular structures influencing their binding to protein which may open up new avenues for the design of the most suitable flavonoids derivatives with structure variants.
Presson, Nora; Beers, Sue R; Morrow, Lisa; Wagener, Lauren M; Bird, William A; Van Eman, Gina; Krishnaswamy, Deepa; Penderville, Joshua; Borrasso, Allison J; Benso, Steven; Puccio, Ava; Fissell, Catherine; Okonkwo, David O; Schneider, Walter
2015-09-01
To realize the potential value of tractography in traumatic brain injury (TBI), we must identify metrics that provide meaningful information about functional outcomes. The current study explores quantitative metrics describing the spatial properties of tractography from advanced diffusion imaging (High Definition Fiber Tracking, HDFT). In a small number of right-handed males from military TBI (N = 7) and civilian control (N = 6) samples, both tract homologue symmetry and tract spread (proportion of brain mask voxels contacted) differed for several tracts among civilian controls and extreme groups in the TBI sample (high scorers and low scorers) for verbal recall, serial reaction time, processing speed index, and trail-making. Notably, proportion of voxels contacted in the arcuate fasciculus distinguished high and low performers on the CVLT-II and PSI, potentially reflecting linguistic task demands, and GFA in the left corticospinal tract distinguished high and low performers in PSI and Trail Making Test Part A, potentially reflecting right hand motor response demands. The results suggest that, for advanced diffusion imaging, spatial properties of tractography may add analytic value to measures of tract anisotropy.
[Formation of microbial biofilms in causative agents of acute and chronic pyelonephritis].
Lagun, L V; Atanasova, Iu V; Tapal'skiĭ, D V
2013-01-01
Study the intensity of formation of microbial biofilms by Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus strains isolated during various forms of pyelonephritis. 150 clinical isolates of microorganisms isolated from urine ofpatientswith acute and chronic pyelonephritiswere included into the study. Determination of intensity of film-formation was carried out by staining of the formed biofilms by crystal violet with consequent extraction of the dye and measurement of its concentration in washout solution. Among causative agents ofpyelonephritis P. aeruginosa isolates had the maximum film-forming ability. The intensity of biofilm formation of these isolates was 2-3 time higher than staphylococcus and enterobacteria strains. Strains isolated from patients with chronic pyelonephritis by ability to form biofilms significantly surpassed strains isolated from acute pyelonephritis patients. A higher ability to form microbial biofilms for microorganisms--causative agents of pyelonephritis progressing against the background ofurolithiasis was noted. The ability to form biofilms is determined by both causative agent species and character of the infectious process in which this microorganism participates. Intensive formation of biofilms by E. coli, P. aeruginosa, K. pneumoniae, S. aureus clinical isolates may be an important factor of chronization of urinary tract infections.
Ma, Jui-Shan; Chen, Sin-Yu; Lo, Hsueh-Hsia
2017-11-01
Biofilm formation has been well known as a determinant of bacterial virulence. Group G Streptococcus dysgalactiae subspecies equisimilis (SDSE), a relevant pathogen with increasing medical importance, was evaluated for the biofilm-forming potential. Microtiter plate assay was used to assess the most feasible medium for group G SDSE to form a biofilm. Among 246 SDSE isolates examined, 46.7%, 43.5%, 33.3%, and 26.4% of isolates showed moderate or strong biofilm-forming abilities using tryptic soy broth (TSB), brain heart infusion broth (BHI), Todd-Hewitt broth (THB), and C medium with 30 mM glucose (CMG), respectively. The addition of glucose significantly increased the biofilm-forming ability of group G SDSE. FCT (fibronectin-collagen-T-antigen) typing of SDSE was first undertaken and 11 FCT types were found. Positive associations of stG10.0 or negative associations of stG245.0, stG840.0, and stG6.1 with biofilm-forming ability of SDSE were, respectively, found. This was the first investigation demonstrating biofilm-forming potential in clinical group G SDSE isolates; also, some significant associations of biofilm-forming ability with certain emm types were presented. © 2017 APMIS. Published by John Wiley & Sons Ltd.
General George S. Patton was not an Operational Artist
2015-05-21
incompetent leaders, and form an effective staff. While these attributes evolved in his persona through his military training, Patton applied his...highlighted his ability to instill discipline, remove incompetent leaders, and form an effective staff. While these attributes evolved in his persona...His many biographers have highlighted his ability to instill discipline, remove incompetent leaders, and form an effective staff.4 While these
ERIC Educational Resources Information Center
Johnston, Claire S.; Broonen, Jean-Paul; Stauffer, Sarah D.; Hamtiaux, Armanda; Pouyaud, Jacques; Zecca, Gregory; Houssemand, Claude; Rossier, Jerome
2013-01-01
This study presents the validation of a French version of the Career Adapt-Abilities Scale in four Francophone countries. The aim was to re-analyze the item selection and then compare this newly developed French-language form with the international form 2.0. Exploratory factor analysis was used as a tool for item selection, and confirmatory factor…
Effect of modified atmosphere packaging for keeping gel-forming ability of lizardfish
NASA Astrophysics Data System (ADS)
Oka, Hiroyasu; Wang, Xi-Chang
In order to make clear the deterioration and its control for the gel-forming ability of lizardfish, formaldehyde (FA) and tyrosine (Tyr) accumulated in the fillets packaged with air, nitrogen (N2) and oxygen (O2) were determined during storage at 5°C. Amount of Tyr had no increase, however, th at of FA increased especially in the samples packed with N2 on the earlier periods of storage. It was presumed that an enzyme trimethylamine N-oxide demethylase (TMAOase) in the fillets acts sufficiently under oxygen-deficient storage, and the produced FA is rapidly combined with fish protein, causing the deterioration of the gel-forming ability, before protease of fillets act on the fish protein. These findings suggested that avoidance of oxygen deficiency during storage is eftective to keep gelforming ability of lizardfish.
Pareniuk, O Iu; Moshynets', O V; Tytova, L V; Levchuk, S Ie
2013-01-01
Qualitative composition of the dominating forms of microorganisms isolated from radionuclide contaminated soils has been studied. The ability to accumulate 137Cs by freshly isolated species and collection cultures that were not adapted to the presence of the radionuclide has been analyzed. It is shown that among the analyzed microorganisms the greatest ability to accumulate the radionuclide is inherent in the collection culture Bacillus megaterium UKMV-5724.
Children's Effort/Ability Reasoning: Individual Differences and Motivational Consequences.
ERIC Educational Resources Information Center
Leggett, Ellen L.; Dweck, Carol S.
Individual differences in same-aged children's reasoning about effort and ability, as well as the consequences of different forms of reasoning in actual achievement situations, were investigated. It was hypothesized that different forms of children's reasoning would be related to different (helpless versus mastery-oriented) motivational patterns.…
ERIC Educational Resources Information Center
Teixeira, Marco Antonio Pereira; Bardagi, Marucia Patta; Lassance, Maria Celia Pacheco; Magalhaes, Mauro de Oliveira; Duarte, Maria Eduarda
2012-01-01
The Career Adapt-Abilities Scale--Brazilian Form (CAASBrazil) consists of four scales which measure concern, control, curiosity, and confidence as psychosocial resources for managing occupational transitions, developmental tasks, and work traumas. Internal consistency estimates for the subscale and total scores ranged from good to excellent. The…
NASA Astrophysics Data System (ADS)
Wang, Cuicui; Wang, Feng; Han, Yong
2016-01-01
In this study, the tantalum oxide coatings were formed on pure tantalum (Ta) by micro-arc oxidation (MAO) in electrolytic solutions of calcium acetate and β-glycerophosphate disodium, and the effect of the applied voltage on the microstructure and bond strength of the MAO coatings was systematically investigated. The effect of annealing treatment on the microstructure, bond strength and apatite-inducing ability of the MAO coatings formed at 350 and 450 V was also studied. The study revealed that during the preparation of tantalum oxide coatings on Ta substrate by MAO, the applied voltage considerably affected the phase components, morphologies and bond strength of the coatings, but had little effect on surface chemical species. After annealing treatment, newly formed CaTa4O11 phase mainly contributed to the much more stronger apatite-inducing ability of the annealed tantalum oxide coatings than those that were not annealed. The better apatite-inducing ability of the MAO coatings formed at 450 V compared to those formed at 350 V was attributed to the less amorphous phase and more crystalline phase as well as more Ca and P contained in the MAO coatings with increasing the applied voltage.
ERIC Educational Resources Information Center
Akyuz, Halil Ibrahim; Keser, Hafize
2015-01-01
The aim of this study is to investigate the effect of an educational agent, used in online task based learning media, and its form characteristics on problem solving ability perceptions of students. 2x2 factorial design is used in this study. The first study factor is the role of the educational agent and the second factor is form characteristics…
Career Adapt-Abilities Scale-USA Form: Psychometric Properties and Relation to Vocational Identity
ERIC Educational Resources Information Center
Porfeli, Erik J.; Savickas, Mark L.
2012-01-01
This article reports construction and initial validation of the United States form of the Career Adapt-Abilities Scale (CAAS). The CAAS consists of four scales, each with six items, which measure concern, control, curiosity, and confidence as psychosocial resources for managing occupational transitions, developmental tasks, and work traumas.…
Role of Peers in Student Academic Achievement in Exogenously Formed University Groups
ERIC Educational Resources Information Center
Androushchak, Gregory; Poldin, Oleg; Yudkevich, Maria
2013-01-01
We estimate the influence of classmates' ability characteristics on student achievement in exogenously formed university student groups. The study uses administrative data on undergraduate students at a large selective university in Russia. The presence of high-ability classmates has a significant positive effect on individual grades in key…
Biofilm forming ability of bacteria isolated from necrotic roots canals of teeth
NASA Astrophysics Data System (ADS)
Alwan, Merriam Ghadhanfar; Usup, Gires; Heng, Lee Yook; Ahmad, Asmat
2018-04-01
The growth of microbes in biofilms are associated with repeated and chronic human infections and are extremely resistant to antimicrobial agents. The purpose of this study was to determine the diversity of bacteria from necrotic roots canals of teeth and to detect their biofilm formation ability. A total of 42 bacterial isolates were isolated and identified as belonging to 11 genera. These are Enterococcus sp. (21.4%) followed by Streptococcus sp. (16.8%), Bacillus sp. (11.9%), Peptostreptococcus sp. (9.5%), Staphylococcus sp. (9.5%), Bacteroides sp. (7.1%), Clostridium sp. (7.1%), Actinomyces sp. (7.1%), Fusobacterium sp. (4.76%), Provotella sp. (2.4%) and Chromobacterium sp. (2.4%). Three screening methods for biofilm forming ability were used. Congo Red Agar method (CRA), Tube method (TM) and Microtitre Plate (MTP). From the results, MTP method is a more reliable and quantitative method for the screening and detection of microorganism's ability to form biofilm. This method can be recommended and suggested as a general screening method for the detection of biofilm forming bacteria isolated from roots canals of teeth.
Vogeleer, Philippe; Tremblay, Yannick D. N.; Jubelin, Grégory; Jacques, Mario
2015-01-01
Forming biofilms may be a survival strategy of Shiga toxin-producing Escherichia coli to enable it to persist in the environment and the food industry. Here, we evaluate and characterize the biofilm-forming ability of 39 isolates of Shiga toxin-producing Escherichia coli isolates recovered from human infection and belonging to seropathotypes A, B, or C. The presence and/or production of biofilm factors such as curli, cellulose, autotransporter, and fimbriae were investigated. The polymeric matrix of these biofilms was analyzed by confocal microscopy and by enzymatic digestion. Cell viability and matrix integrity were examined after sanitizer treatments. Isolates of the seropathotype A (O157:H7 and O157:NM), which have the highest relative incidence of human infection, had a greater ability to form biofilms than isolates of seropathotype B or C. Seropathotype A isolates were unique in their ability to produce cellulose and poly-N-acetylglucosamine. The integrity of the biofilms was dependent on proteins. Two autotransporter genes, ehaB and espP, and two fimbrial genes, z1538 and lpf2, were identified as potential genetic determinants for biofilm formation. Interestingly, the ability of several isolates from seropathotype A to form biofilms was associated with their ability to agglutinate yeast in a mannose-independent manner. We consider this an unidentified biofilm-associated factor produced by those isolates. Treatment with sanitizers reduced the viability of Shiga toxin-producing Escherichia coli but did not completely remove the biofilm matrix. Overall, our data indicate that biofilm formation could contribute to the persistence of Shiga toxin-producing Escherichia coli and specifically seropathotype A isolates in the environment. PMID:26712549
Vogeleer, Philippe; Tremblay, Yannick D N; Jubelin, Grégory; Jacques, Mario; Harel, Josée
2015-12-28
Forming biofilms may be a survival strategy of Shiga toxin-producing Escherichia coli to enable it to persist in the environment and the food industry. Here, we evaluate and characterize the biofilm-forming ability of 39 isolates of Shiga toxin-producing Escherichia coli isolates recovered from human infection and belonging to seropathotypes A, B, or C. The presence and/or production of biofilm factors such as curli, cellulose, autotransporter, and fimbriae were investigated. The polymeric matrix of these biofilms was analyzed by confocal microscopy and by enzymatic digestion. Cell viability and matrix integrity were examined after sanitizer treatments. Isolates of the seropathotype A (O157:H7 and O157:NM), which have the highest relative incidence of human infection, had a greater ability to form biofilms than isolates of seropathotype B or C. Seropathotype A isolates were unique in their ability to produce cellulose and poly-N-acetylglucosamine. The integrity of the biofilms was dependent on proteins. Two autotransporter genes, ehaB and espP, and two fimbrial genes, z1538 and lpf2, were identified as potential genetic determinants for biofilm formation. Interestingly, the ability of several isolates from seropathotype A to form biofilms was associated with their ability to agglutinate yeast in a mannose-independent manner. We consider this an unidentified biofilm-associated factor produced by those isolates. Treatment with sanitizers reduced the viability of Shiga toxin-producing Escherichia coli but did not completely remove the biofilm matrix. Overall, our data indicate that biofilm formation could contribute to the persistence of Shiga toxin-producing Escherichia coli and specifically seropathotype A isolates in the environment. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
Density and glass forming ability in amorphous atomic alloys: The role of the particle softness
DOE Office of Scientific and Technical Information (OSTI.GOV)
Douglass, Ian; Hudson, Toby; Harrowell, Peter
A key property of glass forming alloys, the anomalously small volume difference with respect to the crystal, is shown to arise as a direct consequence of the soft repulsive potentials between metals. This feature of the inter-atomic potential is demonstrated to be responsible for a significant component of the glass forming ability of alloys due to the decrease in the enthalpy of fusion and the associated depression of the freezing point.
Thermodynamic behavior of glassy state of structurally related compounds.
Kaushal, Aditya Mohan; Bansal, Arvind Kumar
2008-08-01
Thermodynamic properties of amorphous pharmaceutical forms are responsible for enhanced solubility as well as poor physical stability. The present study was designed to investigate the differences in thermodynamic parameters arising out of disparate molecular structures and associations for four structurally related pharmaceutical compounds--celecoxib, valdecoxib, rofecoxib, and etoricoxib. Conventional and modulated temperature differential scanning calorimetry were employed to study glass forming ability and thermodynamic behavior of the glassy state of model compounds. Glass transition temperature of four glassy compounds was in a close range of 327.6-331.8 K, however, other thermodynamic parameters varied considerably. Kauzmann temperature, strength parameter and fragility parameter showed rofecoxib glass to be most fragile of the four compounds. Glass forming ability of the compounds fared similar in the critical cooling rate experiments, suggesting that different factors were determining the glass forming ability and subsequent behavior of the compounds in glassy state. A comprehensive understanding of such thermodynamic facets of amorphous form would help in rationalizing the approaches towards development of stable glassy pharmaceuticals.
O'Leary, Denis; Cabe, Evonne M Mc; McCusker, Matthew P; Martins, Marta; Fanning, Séamus; Duffy, Geraldine
2013-01-15
The purpose of this study was to characterise 172 Salmonella Typhimurium isolates taken from the pork chain for their biofilm forming abilities and to analyse their potential to survive on food processing surfaces. Many Salmonella have the ability to form biofilms. These natural structures, elaborated by bacteria are important in food production because their formation contributes to bacterial survival. Adherent bacterial cells are more resilient to displacement strategies including physical and chemical procedures as a consequence of their altered more resistant phenotype. By improving our understanding of the nature of biofilms, this data could positively contribute to the development and implementation of eradication strategies. In this study, Salmonella Typhimurium DT104 and DT104b were investigated for their ability to form biofilms on a range of different surfaces under defined environmental growth conditions. Phenotypic characterisation involved examining colony morphology on indicator agars, assessing their ability to survive chlorine-based challenges and investigating their ability to attach to stainless steel and to plastic surfaces. All bacterial isolates were investigated for the presence of Salmonella genomic island I (SGI1) which is thought to enhance efficient biofilm formation. It was found that the majority of strains possess biofilm forming capabilities but successful attachment is highly dependent on the surface on which the biofilm is forming. The strains readily attached to stainless steel and plastic surfaces and survived high chlorine concentrations. Molecular and phenotypic comparisons of strong and weak biofilm forming strains indicate that biofilm development is not solely dependent on the acquirement of SGI1. Copyright © 2012 Elsevier B.V. All rights reserved.
Linking Outcomes from Peabody Picture Vocabulary Test Forms Using Item Response Models
ERIC Educational Resources Information Center
Hoffman, Lesa; Templin, Jonathan; Rice, Mabel L.
2012-01-01
Purpose: The present work describes how vocabulary ability as assessed by 3 different forms of the Peabody Picture Vocabulary Test (PPVT; Dunn & Dunn, 1997) can be placed on a common latent metric through item response theory (IRT) modeling, by which valid comparisons of ability between samples or over time can then be made. Method: Responses…
Cognitive Abilities of Children With Neurological and Liver Forms of Wilson Disease.
Favre, Emilie; Lion-François, Laurence; Canton, Marie; Vanlemmens, Claire; Bonneton, Marjorie; Bouillet, Lise; Brunet, Anne-Sophie; Lachaux, Alain
2017-03-01
Cognitive impairment in adult patients experiencing Wilson disease is now more clearly described, even in liver forms of the disease. Although this condition can appear during childhood, the cognitive abilities of children have not yet been reported in a substantial case series. This retrospective study included 21 children with Wilson disease who had undergone general cognitive assessment. The results argue in favor of a poor working memory capacity in the liver form of the disease, and more extensive cognitive impairments in its neurological form. Extensive neuropsychological investigations on all children experiencing Wilson disease are thus required.
Paired-Associate Learning Ability Accounts for Unique Variance in Orthographic Learning
ERIC Educational Resources Information Center
Wang, Hua-Chen; Wass, Malin; Castles, Anne
2017-01-01
Paired-associate learning is a dynamic measure of the ability to form new links between two items. This study aimed to investigate whether paired-associate learning ability is associated with success in orthographic learning, and if so, whether it accounts for unique variance beyond phonological decoding ability and orthographic knowledge. A group…
NASA Astrophysics Data System (ADS)
Dixon, D.; Babu, D. J.; Langner, J.; Bruns, M.; Pfaffmann, L.; Bhaskar, A.; Schneider, J. J.; Scheiba, F.; Ehrenberg, H.
2016-11-01
Oxygen plasma treatment was applied on commercially available graphite felt electrodes based on rayon (GFA) and polyacrylonitrile (GFD). The formation of functional groups on the surface of the felt was confirmed by X-ray photoelectron spectroscopy measurements. The BET studies of the plasma treated electrodes showed no significant increase in surface area for both the rayon as well as the PAN based felts. Both plasma treated electrodes showed significantly enhanced V3+/V2+ redox activity compared to the pristine electrodes. Since an increase of the surface area has been ruled out for plasma treated electrode the enhanced activity could be attributed to surface functional groups. Interestingly, plasma treated GFD felts showed less electrochemical activity towards V5+/V4+ compared to the pristine electrode. Nevertheless, an overall increase of the single cell performance was still observed as the negative electrode is known to be the performance limiting electrode. Thus, to a great extent the present work helps to preferentially understand the importance of functional groups on the electrochemical activity of negative and positive redox reaction. The study emphasizes the need of highly active electrodes especially at the negative electrode side as inactive electrodes can still facilitate hydrogen evolution and degrade the electrolyte in VRFBs.
Dai, Yujie; Chen, Nan; Wang, Qiang; Zheng, Heng; Zhang, Xiuli; Jia, Shiru; Dong, Lilong; Feng, Dacheng
2012-01-01
The inhibitors of p53-HDM2 interaction are attractive molecules for the treatment of wild-type p53 tumors. In order to search more potent HDM2 inhibitors, docking operation with CDOCKER protocol in Discovery Studio 2.1 (DS2.1) and multidimensional hybrid quantitative structure-activity relationship (QSAR) studies through the physiochemical properties obtained from DS2.1 and E-Dragon 1.0 as descriptors, have been performed on 59 1,4-benzodiazepine- 2,5-diones which have p53-HDM2 interaction inhibitory activities. The docking results indicate that π-π interaction between the imidazole group in HIS96 and the aryl ring at 4-N of 1,4-benzodiazepine-2,5-dione may be one of the key factors for the combination of ligands with HDM2. Two QSAR models were obtained using genetic function approximation (GFA) and genetic partial least squares (G/PLS) based on the descriptors obtained from DS2.1 and E-dragon 1.0, respectively. The best model can explain 85.5% of the variance (R 2adj ) while it could predict 81.7% of the variance (R 2 cv ). With this model, the bioactivities of some new compounds were predicted. PMID:24250508
Dai, Yujie; Chen, Nan; Wang, Qiang; Zheng, Heng; Zhang, Xiuli; Jia, Shiru; Dong, Lilong; Feng, Dacheng
2012-01-01
The inhibitors of p53-HDM2 interaction are attractive molecules for the treatment of wild-type p53 tumors. In order to search more potent HDM2 inhibitors, docking operation with CDOCKER protocol in Discovery Studio 2.1 (DS2.1) and multidimensional hybrid quantitative structure-activity relationship (QSAR) studies through the physiochemical properties obtained from DS2.1 and E-Dragon 1.0 as descriptors, have been performed on 59 1,4-benzodiazepine- 2,5-diones which have p53-HDM2 interaction inhibitory activities. The docking results indicate that π-π interaction between the imidazole group in HIS96 and the aryl ring at 4-N of 1,4-benzodiazepine-2,5-dione may be one of the key factors for the combination of ligands with HDM2. Two QSAR models were obtained using genetic function approximation (GFA) and genetic partial least squares (G/PLS) based on the descriptors obtained from DS2.1 and E-dragon 1.0, respectively. The best model can explain 85.5% of the variance (R (2) adj ) while it could predict 81.7% of the variance (R (2) cv ). With this model, the bioactivities of some new compounds were predicted.
Suvilampi, J E; Rintala, J A
2004-01-01
Thermophilic aerobic treatment of settled pulp and paper mill effluent was studied under mill premises with two comparative pilot processes; suspended carrier biofilm process (SCBP) and activated sludge process (ASP). Full-scale mesophilic activated sludge process was a reference treatment. During the runs (61 days) hydraulic retention times (HRTs) were kept 13+/-5 h and 16+/-6 h for SCBP and ASP, respectively. Corresponding volumetric loadings rates (VLR) were 2.7+/-0.9 and 2.2+/-1.0 kg CODfilt m(-3)d(-1). Temperatures varied between 46 to 60 degrees C in both processes. Mesophilic ASP was operated with HRT of 36 h, corresponding VLR of 0.7 kg CODfilt m(-3)d(-1). Both SCBP and ASP achieved CODfilt (GF/A filtered) removals up to 85%, while the mesophilic ASP removal was 89+/-2%. NTU values were markedly higher (100-300) in thermophilic effluents than in mesophilic effluent (30). Effluent turbidity was highly dependent on temperature; in batch experiment mesophilic effluent sample had NTU values of 30 and 60 at 35 degrees C and 55 degrees C, respectively. As a conclusion, both thermophilic treatments gave high CODfilt removals, which were close to mesophilic process removal and were achieved with less than half of HRT.
Automated Rock Identification for Future Mars Exploration Missions
NASA Technical Reports Server (NTRS)
Gulick, V. C.; Morris, R. L.; Gazis, P.; Bishop, J. L.; Alena, R.; Hart, S. D.; Horton, A.
2003-01-01
A key task for human or robotic explorers on the surface of Mars is choosing which particular rock or mineral samples should be selected for more intensive study. The usual challenges of such a task are compounded by the lack of sensory input available to a suited astronaut or the limited downlink bandwidth available to a rover. Additional challenges facing a human mission include limited surface time and the similarities in appearance of important minerals (e.g. carbonates, silicates, salts). Yet the choice of which sample to collect is critical. To address this challenge we are developing science analysis algorithms to interface with a Geologist's Field Assistant (GFA) device that will allow robotic or human remote explorers to better sense and explore their surroundings during limited surface excursions. We aim for our algorithms to interpret spectral and imaging data obtained by various sensors. The algorithms, for example, will identify key minerals, rocks, and sediments from mid-IR, Raman, and visible/near-IR spectra as well as from high resolution and microscopic images to help interpret data and to provide high-level advice to the remote explorer. A top-level system will consider multiple inputs from raw sensor data output by imagers and spectrometers (visible/near-IR, mid-IR, and Raman) as well as human opinion to identify rock and mineral samples.
Hosseinbor, A. Pasha; Chung, Moo K.; Wu, Yu-Chien; Alexander, Andrew L.
2012-01-01
The ensemble average propagator (EAP) describes the 3D average diffusion process of water molecules, capturing both its radial and angular contents. The EAP can thus provide richer information about complex tissue microstructure properties than the orientation distribution function (ODF), an angular feature of the EAP. Recently, several analytical EAP reconstruction schemes for multiple q-shell acquisitions have been proposed, such as diffusion propagator imaging (DPI) and spherical polar Fourier imaging (SPFI). In this study, a new analytical EAP reconstruction method is proposed, called Bessel Fourier orientation reconstruction (BFOR), whose solution is based on heat equation estimation of the diffusion signal for each shell acquisition, and is validated on both synthetic and real datasets. A significant portion of the paper is dedicated to comparing BFOR, SPFI, and DPI using hybrid, non-Cartesian sampling for multiple b-value acquisitions. Ways to mitigate the effects of Gibbs ringing on EAP reconstruction are also explored. In addition to analytical EAP reconstruction, the aforementioned modeling bases can be used to obtain rotationally invariant q-space indices of potential clinical value, an avenue which has not yet been thoroughly explored. Three such measures are computed: zero-displacement probability (Po), mean squared displacement (MSD), and generalized fractional anisotropy (GFA). PMID:22963853
Vergara, Alberto; Normanno, Giovanni; Di Ciccio, Pierluigi; Pedonese, Francesca; Nuvoloni, Roberta; Parisi, Antonio; Santagada, Gianfranco; Colagiorgi, Angelo; Zanardi, Emanuela; Ghidini, Sergio; Ianieri, Adriana
2017-10-01
The capability to produce biofilm is an important persistence and dissemination mechanism of some foodborne bacteria. This paper investigates the relationship between some molecular characteristics (SCCmec, ST, spa-type, agr-type, cna, sarA, icaA, icaD, clfA, fnbA, fnbB, hla, hlb) of 22 food-related methicillin-resistant Staphylococcus aureus (MRSA) strains and their ability to form biofilm on stainless steel and polystyrene. Five (22.7%, 5/22) strains were able to synthesize biofilm on polystyrene, and one of these (4.5%, 1/22) strains was also able to synthesize biofilm on stainless steel. The largest amount of biofilm was formed on polystyrene by 2 MRSA strains isolated from cows' milk, thus raising concern about the dairy industry. The majority of MRSA biofilm producers carried SCCmec type IVa, suggesting that the presence of SCCmecIVa and/or agr type III could be related to the ability to form biofilm. In conclusion, in order to achieve an acceptable level of food safety, Good Hygiene Practices should be strictly implemented along the food chain to reduce the risk of colonization and dissemination of MRSA biofilm-producing strains in the food industry. In this study, some assayed isolates of food-related MRSA demonstrated the capacity to form biofilm. Biofilm formation differed according to surface characteristics and MRSA strains. A relationship was observed between some molecular characteristics and the ability to form biofilms. Few studies have investigated the ability of MRSA to form biofilms, and the majority of these studies have investigated clinical aspects. This work was performed to investigate whether or not there is a difference between MRSA food isolates and MRSA clinical isolates in their ability to form biofilm. These initial findings could provide information that will contribute to a better understanding of these aspects. © 2017 Institute of Food Technologists®.
Obaid, Najla A; Jacobson, Glenn A; Tristram, Stephen
2015-03-01
Nontypeable Haemophilus influenzae (NTHi) is an opportunistic pathogen associated with a range of infections, including various lower respiratory infections, otitis media, and conjunctivitis. There is some debate as to whether or not NTHi produces biofilms and, if so, whether or not this is relevant to pathogenesis. Although many studies have examined the association between in vitro biofilm formation and isolates from a specific infection type, few have made comparisons from isolates from a broad range of isolates grouped by clinical source. In our study 50 NTHi from different clinical sources, otitis media, conjunctivitis, lower respiratory tract infections in both cystic fibrosis and non-cystic fibrosis patients, and nasopharyngeal carriage, plus 10 nasopharyngeal isolates of the commensal Haemophilus haemolyticus were tested for the ability to form biofilm by using a static microtitre plate crystal violet assay. A high degree of variation in biofilm forming ability was observed across all isolates, with no statistically significant differences observed between the groups, with the exception of the isolates from conjunctivitis. These isolates had uniformly lower biofilm forming ability compared with isolates from the other groups (p < 0.005).
Zara, Giacomo; Zara, Severino; Pinna, Claudia; Marceddu, Salvatore; Budroni, Marilena
2009-12-01
In Saccharomyces cerevisiae, FLO11 encodes an adhesin that is associated with different phenotypes, such as adherence to solid surfaces, hydrophobicity, mat and air-liquid biofilm formation. In the present study, we analysed FLO11 allelic polymorphisms and FLO11-associated phenotypes of 20 flor strains. We identified 13 alleles of different lengths, varying from 3.0 to 6.1 kb, thus demonstrating that FLO11 is highly polymorphic. Two alleles of 3.1 and 5.0 kb were cloned into strain BY4742 to compare the FLO11-associated phenotypes in the same genetic background. We show that there is a significant correlation between biofilm-forming ability and FLO11 length both in different and in the same genetic backgrounds. Moreover, we propose a multiple regression model that allows prediction of air-liquid biofilm-forming ability on the basis of transcription levels and lengths of FLO11 alleles in a population of S. cerevisiae flor strains. Considering that transcriptional differences are only partially explained by the differences in the promoter sequences, our results are consistent with the hypothesis that FLO11 transcription levels are strongly influenced by genetic background and affect biofilm-forming ability.
Stress Management in Cyst-Forming Free-Living Protists: Programmed Cell Death and/or Encystment
Khan, Naveed Ahmed; Iqbal, Junaid
2015-01-01
In the face of harsh conditions and given a choice, a cell may (i) undergo programmed cell death, (ii) transform into a cancer cell, or (iii) enclose itself into a cyst form. In metazoans, the available evidence suggests that cellular machinery exists only to execute or avoid programmed cell death, while the ability to form a cyst was either lost or never developed. For cyst-forming free-living protists, here we pose the question whether the ability to encyst was gained at the expense of the programmed cell death or both functions coexist to counter unfavorable environmental conditions with mutually exclusive phenotypes. PMID:25648302
Cross-Modal Binding in Developmental Dyslexia
ERIC Educational Resources Information Center
Jones, Manon W.; Branigan, Holly P.; Parra, Mario A.; Logie, Robert H.
2013-01-01
The ability to learn visual-phonological associations is a unique predictor of word reading, and individuals with developmental dyslexia show impaired ability in learning these associations. In this study, we compared developmentally dyslexic and nondyslexic adults on their ability to form cross-modal associations (or "bindings") based…
Clayton, Francina J; Sears, Claire; Davis, Alice; Hulme, Charles
2018-07-01
Paired-associate learning (PAL) tasks measure the ability to form a novel association between a stimulus and a response. Performance on such tasks is strongly associated with reading ability, and there is increasing evidence that verbal task demands may be critical in explaining this relationship. The current study investigated the relationships between different forms of PAL and reading ability. A total of 97 children aged 8-10 years completed a battery of reading assessments and six different PAL tasks (phoneme-phoneme, visual-phoneme, nonverbal-nonverbal, visual-nonverbal, nonword-nonword, and visual-nonword) involving both familiar phonemes and unfamiliar nonwords. A latent variable path model showed that PAL ability is captured by two correlated latent variables: auditory-articulatory and visual-articulatory. The auditory-articulatory latent variable was the stronger predictor of reading ability, providing support for a verbal account of the PAL-reading relationship. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Noordzij, Matthijs L.; Zuidhoek, Sander; Postma, Albert
2006-01-01
The purpose of the present study is twofold: the first objective is to evaluate the importance of visual experience for the ability to form a spatial representation (spatial mental model) of fairly elaborate spatial descriptions. Secondly, we examine whether blind people exhibit the same preferences (i.e. level of performance on spatial tasks) as…
ERIC Educational Resources Information Center
Lentillon-Kaestner, Vanessa; Patelli, Gianpaolo
2016-01-01
The purpose of this study was to estimate the main and interaction effects of grouping forms, student gender and ability level on the pleasure experienced in physical education (PE). The participants included 178 secondary school students (M = 13.17, SD = 0.81), with 72 students enrolled in a basketball unit and 106 students enrolled in an…
Measuring intellectual ability in children with cerebral palsy: can we do better?
Sherwell, Sarah; Reid, Susan M; Reddihough, Dinah S; Wrennall, Jacquie; Ong, Ben; Stargatt, Robyn
2014-10-01
Standard intelligence tests such as the WPPSI-III have limitations when testing children with motor impairment. This study aimed to determine the proportion of children with cerebral palsy with sufficient verbal and motor skills to complete the WPPSI-III, to determine their comparative ability to complete tasks with and without a significant motor component, and to investigate short forms of the WPPSI-III as alternatives. Participants were 78 of 235 eligible 4-5 year old children with cerebral palsy resident in the Australian state of Victoria. Verbal IQ (VIQ), Performance IQ (PIQ), and Full-scale IQ (FSIQ) were determined using the WPPSI-III. Initial screening for pointing and verbal abilities determined which tests were attempted. The impact of speed was investigated by comparing scores on the Block Design subtest with and without an imposed time limit. FSIQ scores were calculated from two short forms of the WPPSI-III and compared to the full form. On screening, 16 children had inadequate pointing (14) and verbal abilities (2). FSIQ was obtained in 62 (82%) children. Strong associations were seen between completion of the entire test battery and topographical pattern, level of manual ability and level of gross motor function. Scores on subtests requiring manual ability were depressed relative to other scores. Children performed better using short forms of the WPPSI-III and, for a minority, when time limits were disregarded. In summary, children with cerebral palsy often lack the fine and gross motor skills necessary to complete the WPPSI-III, scoring relatively poorly on tasks requiring a fine motor response. Using short-form estimations of FSIQ comprised of subtests without a significant fine motor component has the potential to increase a child's FSIQ by approximately 5 points. These findings have important clinical implications when assessing a child with both motor and cognitive limitations. Copyright © 2014 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Yoon, So Yoon; Mann, Eric L.
2017-01-01
Spatial ability has been valued as a talent domain and as an assessment form that reduces cultural, linguistic, and socioeconomic status biases, yet little is known of the spatial ability of students in gifted programs compared with those in general education. Spatial ability is considered an important indicator of potential talent in the domains…
The Measurement of Translation Ability.
ERIC Educational Resources Information Center
Stansfield, Charles W.; And Others
1992-01-01
Variables that constitute translation ability are discussed, based on a two-year development and validation study of job-related tests of translation ability for the Federal Bureau of Investigation. The project involved the development of two parallel forms of the Spanish into English Verbatim Translation Exam (SEVTE). (five references) (LB)
Inheritance in a Diallel Crossing Experiment with Longleaf Pine
E. B. Snyder; Gene Namkoong
1978-01-01
Seven-year-old progeny from crosses among 13 randomly selected parent trees provided genetic information on 51 growth, form, foliage, branch, bud, and pest resistance traits. Presented are he&abilities, phenotypic and genotypic variances, covariances, General Combining Ability (GCA), Specific Combining Ability (SCA), and environmental. correlations for all measured...
Emotion Recognition Abilities and Empathy of Victims of Bullying
ERIC Educational Resources Information Center
Woods, Sarah; Wolke, Dieter; Nowicki, Stephen; Hall, Lynne
2009-01-01
Objectives: Bullying is a form of systematic abuse by peers with often serious consequences for victims. Few studies have considered the role of emotion recognition abilities and empathic behaviour for different bullying roles. This study investigated physical and relational bullying involvement in relation to basic emotion recognition abilities,…
ERIC Educational Resources Information Center
Ronnlund, Michael; Nilsson, Lars-Goran
2008-01-01
To estimate Flynn effects (FEs) on forms of declarative memory (episodic, semantic) and visuospatial ability (Block Design) time-sequential analyses of data for Swedish adult samples (35-80 years) assessed on either of four occasions (1989, 1994, 1999, 2004; n = 2995) were conducted. The results demonstrated cognitive gains across occasions,…
ERIC Educational Resources Information Center
Matlock, Ki Lynn
2013-01-01
When test forms that have equal total test difficulty and number of items vary in difficulty and length within sub-content areas, an examinee's estimated score may vary across equivalent forms, depending on how well his or her true ability in each sub-content area aligns with the difficulty of items and number of items within these areas.…
Maintaining Genome Stability: The Role of Helicases and Deaminases
2008-07-01
deaminases. The cells response to different forms of damage is fundamental to its ability to repair itself when challenged by environmental or...Page 4 of 12 INTRODUCTION Genomic DNA stores all the information for living organisms. The faithful duplication the maintanance of DNA are...maturation of the immune system by modifying enzymes called deaminases. The cells response to different forms of damage is fundamental to its ability to
Innexin-3 forms connexin-like intercellular channels.
Landesman, Y; White, T W; Starich, T A; Shaw, J E; Goodenough, D A; Paul, D L
1999-07-01
Innexins comprise a large family of genes that are believed to encode invertebrate gap junction channel-forming proteins. However, only two Drosophila innexins have been directly tested for the ability to form intercellular channels and only one of those was active. Here we tested the ability of Caenorhabditis elegans family members INX-3 and EAT-5 to form intercellular channels between paired Xenopus oocytes. We show that expression of INX-3 but not EAT-5, induces electrical coupling between the oocyte pairs. In addition, analysis of INX-3 voltage and pH gating reveals a striking degree of conservation in the functional properties of connexin and innnexin channels. These data strongly support the idea that innexin genes encode intercellular channels.
The relationship between form and function level receptive prosodic abilities in autism.
Järvinen-Pasley, Anna; Peppé, Susan; King-Smith, Gavin; Heaton, Pamela
2008-08-01
Prosody can be conceived as having form (auditory-perceptual characteristics) and function (pragmatic/linguistic meaning). No known studies have examined the relationship between form- and function-level prosodic skills in relation to the effects of stimulus length and/or complexity upon such abilities in autism. Research in this area is both insubstantial and inconclusive. Children with autism and controls completed the receptive tasks of the Profiling Elements of Prosodic Systems in Children (PEPS-C) test, which examines both form- and function-level skills, and a sentence-level task assessing the understanding of intonation. While children with autism were unimpaired in both form and function tasks at the single-word level, they showed significantly poorer performance in the corresponding sentence-level tasks than controls. Implications for future research are discussed.
Proteus mirabilis biofilm - qualitative and quantitative colorimetric methods-based evaluation.
Kwiecinska-Piróg, Joanna; Bogiel, Tomasz; Skowron, Krzysztof; Wieckowska, Ewa; Gospodarek, Eugenia
2014-01-01
Proteus mirabilis strains ability to form biofilm is a current topic of a number of research worldwide. In this study the biofilm formation of P. mirabilis strains derived from urine of the catheterized and non-catheterized patients has been investigated. A total number of 39 P. mirabilis strains isolated from the urine samples of the patients of dr Antoni Jurasz University Hospital No. 1 in Bydgoszcz clinics between 2011 and 2012 was used. Biofilm formation was evaluated using two independent quantitative and qualitative methods with TTC (2,3,5-triphenyl-tetrazolium chloride) and CV (crystal violet) application. The obtained results confirmed biofilm formation by all the examined strains, except quantitative method with TTC, in which 7.7% of the strains did not have this ability. It was shown that P. mirabilis rods have the ability to form biofilm on the surfaces of both biomaterials applied, polystyrene and polyvinyl chloride (Nelaton catheters). The differences in ability to form biofilm observed between P. mirabilis strains derived from the urine of the catheterized and non-catheterized patients were not statistically significant.
Cui, Xinyu; Kim, Hyun-Min; Kawashita, Masakazu; Wang, Longbao; Xiong, Tianying; Kokubo, Tadashi; Nakamura, Takashi
2008-04-01
Titanium and its alloys have been widely used for orthopedic implants because of their good biocompatibility. We have previously shown that the crystalline titania layers formed on the surface of titanium metal via anodic oxidation can induce apatite formation in simulated body fluid, whereas amorphous titania layers do not possess apatite-forming ability. In this study, hot water and heat treatments were applied to transform the titania layers from an amorphous structure into a crystalline structure after titanium metal had been anodized in acetic acid solution. The apatite-forming ability of titania layers subjected to the above treatments in simulated body fluid was investigated. The XRD and SEM results indicated hot water and/or heat treatment could greatly transform the crystal structure of titania layers from an amorphous structure into anatase, or a mixture of anatase and rutile. The abundance of Ti-OH groups formed by hot water treatment could contribute to apatite formation on the surface of titanium metals, and subsequent heat treatment would enhance the bond strength between the apatite layers and the titanium substrates. Thus, bioactive titanium metals could be prepared via anodic oxidation and subsequent hot water and heat treatment that would be suitable for applications under load-bearing conditions.
R-Ras Contributes to LTP and Contextual Discrimination
Darcy, Michael J.; Jin, Shan-Xue; Feig, Larry A.
2014-01-01
The ability to discriminate between closely related contexts is a specific form of hippocampal-dependent learning that may be impaired in certain neurodegenerative disorders such as Alzheimer's and Down Syndrome. However, signaling pathways regulating this form of learning are poorly understood. Previous studies have shown that the calcium-dependent exchange factor Ras-GRF1, an activator of Rac, Ras and R-Ras GTPases, is important for this form of learning and memory. Moreover, the ability to discriminate contexts was linked to the ability of Ras-GRF1 to promote high-frequency stimulation (HFS)-LTP via the activation of p38 Map kinase. Here, we show that R-Ras is involved in this form of learning by using virally-delivered miRNAs targeting R-Ras into the CA1 region of dorsal hippocampus and observing impaired contextual discrimination. Like the loss of GRF1, knockdown of R-Ras in the CA1 also impairs the induction of HFS-LTP and p38 Map kinase. Nevertheless, experiments indicate that this involvement of R-Ras in HFS-LTP that is required for contextual discrimination is independent of Ras-GRF1. Thus, R-Ras is a novel regulator of a form of hippocampal-dependent LTP as well as learning and memory that is affected in certain forms of neurodegenerative diseases. PMID:25043327
Effects of partitioned enthalpy of mixing on glass-forming ability
DOE Office of Scientific and Technical Information (OSTI.GOV)
Song, Wen-Xiong; Zhao, Shi-Jin, E-mail: shijin.zhao@shu.edu.cn
2015-04-14
We explore the inherent reason at atomic level for the glass-forming ability of alloys by molecular simulation, in which the effect of partitioned enthalpy of mixing is studied. Based on Morse potential, we divide the enthalpy of mixing into three parts: the chemical part (Δ E{sub nn}), strain part (Δ E{sub strain}), and non-bond part (Δ E{sub nnn}). We find that a large negative Δ E{sub nn} value represents strong AB chemical bonding in AB alloy and is the driving force to form a local ordered structure, meanwhile the transformed local ordered structure needs to satisfy the condition (Δ E{submore » nn}/2 + Δ E{sub strain}) < 0 to be stabilized. Understanding the chemical and strain parts of enthalpy of mixing is helpful to design a new metallic glass with a good glass forming ability. Moreover, two types of metallic glasses (i.e., “strain dominant” and “chemical dominant”) are classified according to the relative importance between chemical effect and strain effect, which enriches our knowledge of the forming mechanism of metallic glass. Finally, a soft sphere model is established, different from the common hard sphere model.« less
Bacterial Biofilms in Chronic Rhinosinusitis and Their Implications for Clinical Management.
Karunasagar, Abhilasha; Garag, Santosh S; Appannavar, Suma B; Kulkarni, Raghavendra D; Naik, Ashok S
2018-03-01
To study the microbiological profile in patients with chronic rhino-sinusitis. To correlate disease severity with the presence of biofilms and host risk factors. To assess outcome of Sinus Surgery 2 weeks post operatively in terms of presence of bacteria and their ability to form biofilm. Prospective study. 50 cases of chronic rhino-sinusitis requiring Functional Endoscopic Sinus Surgery admitted in SDM Hospital, Dharwad, Karnataka were studied using intra-operative mucosal samples for microbiological analysis. The organisms isolated were tested for biofilm forming ability using three in vitro tests. Severity of disease was assessed using SNOT 22 scoring system. Of 50 cases studied, 66% showed presence of chronic rhino-sinusitis with polyposis and had higher SNOT scores compared to those without polyps. Bacterial isolates were obtained from only 17 samples. Staphylococcus species was isolated from 16 samples and Klebsiella pneumoniae from one. 11 Staph spp. isolates showed biofilm forming ability in vitro. Postoperative events in 3 cases yielded biofilm-forming Staphylococcus. Staphylococcus was the most dominant organism isolated and 11 isolates were biofilm formers. Thus the detection of biofilm forming organisms can be considered as a negative prognostic indicator and should forewarn the surgeon about the risk of recurrence.
The presence of biofilm forming microorganisms on hydrotherapy equipment and facilities.
Jarząb, Natalia; Walczak, Maciej
2017-10-01
Hydrotherapy equipment provides a perfect environment for the formation and growth of microbial biofilms. Biofilms may reduce the microbiological cleanliness of hydrotherapy equipment and harbour opportunistic pathogens and pathogenic bacteria. The aims of this study were to investigate the ability of microorganisms that colonize hydrotherapy equipment to form biofilms, and to assess the influence of temperature and nutrients on the rate of biofilm formation. Surface swab samples were collected from the whirlpool baths, inhalation equipment and submerged surfaces of a brine pool at the spa center in Ciechocinek, Poland. We isolated and identified microorganisms from the swab samples and measured their ability to form biofilms. Biofilm formation was observed at a range of temperatures, in both nutrient-deficient and nutrient-rich environments. We isolated and identified microorganisms which are known to form biofilms on medical devices (e.g. Stenotrophomonas maltophilia). All isolates were classified as opportunistic pathogens, which can cause infections in humans with weakened immunity systems. All isolates showed the ability to form biofilms in the laboratory conditions. The potential for biofilm formation was higher in the presence of added nutrients. In addition, the hydrolytic activity of the biofilm was connected with the presence of nutrients.
Genetics Home Reference: Huntington disease
... in personality and a decline in thinking and reasoning abilities. Individuals with the adult-onset form of ... and drooling. School performance declines as thinking and reasoning abilities become impaired. Seizures occur in 30 percent ...
Adult Second Language Learners' Pragmatic Development in the Study-Abroad Context: A Review
ERIC Educational Resources Information Center
Xiao, Feng
2015-01-01
The ability to use language effectively in communication is regarded as important as knowledge of grammatical rules in the communicative competence models. Pragmatic competence, namely the ability to understand and use linguistic forms appropriately according to context, is thus accepted as a vital component of language ability. Recently,…
ERIC Educational Resources Information Center
Jose, Kshema
2016-01-01
Current workplace demands newer forms of literacies that go beyond the ability to decode print. These involve not only competence to operate digital tools, but also the ability to create, represent, and share meaning in different modes and formats; ability to interact, collaborate and communicate effectively using digital tools, and engage…
NASA Astrophysics Data System (ADS)
Nurlaila, L.; Sriyati, S.; Riandi
2017-02-01
The purpose of this research is to describe the profile of misconceptions and scientific argumentation ability using Diagnostic Question Cluster (DQCs) of molecular genetics concept. This research use descriptive research method and biology education students as a research subject. The Instrument that used in this research are DQCs, sheets interviews, observations, and field notes. The DQCs tested by writing and oral that used to analyze misconceptions and scientific argumentation ability. Sheets interviews, observations and field notes, are used to analyze the possible factors causing misconceptions and scientific argumentation ability. The results showed that misconception of molecular genetics are: DNA (23.75%), genes (18.75%) of chromosomes (15%) and protein synthesis (5.5%). The pattern of the highest misconceptions owned Misconception-Understand Partial. The average scientific argumentation ability is 55% and still categorized warrant (W). The pattern of the scientific argumentation abilities formed is level 2 to level 2 that consists of the arguments in the form of a claim with a counter claim that accompanied by data, collateral (warrant) or support (backing) but does not contain a disclaimer (rebutal).
Liefting, Maartje; Hoedjes, Katja M; Lann, Cécile Le; Smid, Hans M; Ellers, Jacintha
2018-05-16
We are only starting to understand how variation in cognitive ability can result from local adaptations to environmental conditions. A major question in this regard is to what extent selection on cognitive ability in a specific context affects that ability in general through correlated evolution. To address this question we performed artificial selection on visual associative learning in female Nasonia vitripennis wasps. Using appetitive conditioning in which a visual stimulus was offered in association with a host reward, the ability to learn visual associations was enhanced within 10 generations of selection. To test for correlated evolution affecting this form of learning, the ability to readily form learned associations in females was also tested using an olfactory instead of a visual stimulus in the appetitive conditioning. Additionally, we assessed whether the improved associative learning ability was expressed across sexes by colour-conditioning males with a mating reward. Both females and males from the selected lines consistently demonstrated an increased associative learning ability compared to the control lines, independent of learning context or conditioned stimulus. No difference in relative volume of brain neuropils was detected between the selected and control lines. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Non-periodic high-index contrast gratings reflector with large-angle beam forming ability
NASA Astrophysics Data System (ADS)
Fang, Wenjing; Huang, Yongqing; Duan, Xiaofeng; Fei, Jiarui; Ren, Xiaomin; Mao, Min
2016-05-01
A non-periodic high-index contrast gratings (HCGs) reflector on SOI wafer with large-angle beam forming ability has been proposed and fabricated. The proposed reflector was designed using rigorous coupled-wave analysis (RCWA) and finite-element-method (FEM). A deflection angle of 17.35° and high reflectivity of 92.31% are achieved under transverse magnetic (TM) polarized light in numerical simulation. Experimental results show that the reflected power peaked at 17.2° under a 1550 nm incident light, which is in good accordance with the simulation results. Moreover, the reflected power spectrum was also measured. Under different incident wavelengths around 1550 nm, reflected powers all peaked at 17.2°. The results show that the proposed non-periodic HCGs reflector has a good reflection and beam forming ability in a wavelength range as wide as 40 nm around 1550 nm.
Wass, Christopher; Denman-Brice, Alexander; Rios, Chris; Light, Kenneth R; Kolata, Stefan; Smith, Andrew M; Matzel, Louis D
2012-04-01
Contemporary descriptions of human intelligence hold that this trait influences a broad range of cognitive abilities, including learning, attention, and reasoning. Like humans, individual genetically heterogeneous mice express a "general" cognitive trait that influences performance across a diverse array of learning and attentional tasks, and it has been suggested that this trait is qualitatively and structurally analogous to general intelligence in humans. However, the hallmark of human intelligence is the ability to use various forms of "reasoning" to support solutions to novel problems. Here, we find that genetically heterogeneous mice are capable of solving problems that are nominally indicative of inductive and deductive forms of reasoning, and that individuals' capacity for reasoning covaries with more general learning abilities. Mice were characterized for their general learning ability as determined by their aggregate performance (derived from principal component analysis) across a battery of five diverse learning tasks. These animals were then assessed on prototypic tests indicative of deductive reasoning (inferring the meaning of a novel item by exclusion, i.e., "fast mapping") and inductive reasoning (execution of an efficient search strategy in a binary decision tree). The animals exhibited systematic abilities on each of these nominal reasoning tasks that were predicted by their aggregate performance on the battery of learning tasks. These results suggest that the coregulation of reasoning and general learning performance in genetically heterogeneous mice form a core cognitive trait that is analogous to human intelligence. (c) 2012 APA, all rights reserved.
Students’ conceptions and problem-solving ability on topic chemical thermodynamics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Diawati, Chansyanah, E-mail: chansyanahd@yahoo.com
The enthalpy concept and its change were introduced to describe the forms of internal energy transfer in chemical reactions. Likewise, the concepts of exothermic and endothermic reactions introduced as a consequence of heat transfer form. In the heat measurement process at constant pressure, work is often ignored. The exothermic or endothermic reactions, usually only based on the increase or decrease of the reaction temperature, without associated with the internal energy. Depictions of enthalpy and its change assumed closely related to students’ problem-solving ability. Therefore, the study to describe pre-service chemistry teacher student’s conceptions and problem-solving ability on topic chemical thermodynamicsmore » has been done. This research was a case study of chemical education course in Provinsi Lampung. The subjects of this study were 42 students who attend the chemical thermodynamics course. Questions about exothermic and endothermic reactions, enthalpy and its change, as well as internal energy and its change were given in the form of an essay exam questions. Answers related to conception qualitatively categorized, while problem solving answers were scored and assessed. The results showed that, in general, students were having problems in enthalpy and describe the changes in the form of heat and work. The highest value of problem solving ability obtained 26.67 from the maximum value of 100. The lowest value was 0, and the average value was 14.73. These results show that the problem-solving ability of pre-service chemistry teacher students was low. The results provide insight to researchers, and educators to develop learning or lab work on this concept.« less
ERIC Educational Resources Information Center
Daugirdiene, Ausra; Petrulyte, Aiste; Brandisauskiene, Agne
2018-01-01
The understanding and generalisation of causality are important thinking abilities, as they form the basis for a person's activity. Researchers exploring these abilities do not have a unified opinion regarding the age of children when they develop causative understanding and its determinant factors (e.g. age, prior knowledge, the content of a…
Correlates of the Ability to Use Context Clues in Reading.
ERIC Educational Resources Information Center
Dulin, Kenneth L.
Results of two studies of the ability to use specific context clues and possible academic correlates of this ability are reported. In the first study, a five-form data-gathering instrument, using categories of context clues derived from Artley, Betts, and McCullough, was administered to 315 tenth-grade students in Seattle, Washington. Simulated…
Information Processing from Infancy to 11 Years: Continuities and Prediction of IQ
ERIC Educational Resources Information Center
Rose, Susan A.; Feldman, Judith F.; Jankowski, Jeffery J.; Van Rossem, Ronan
2012-01-01
This study provides the first direct evidence of cognitive continuity for multiple specific information processing abilities from infancy and toddlerhood to pre-adolescence, and provides support for the view that infant abilities form the basis of later childhood abilities. Data from a large sample of children (N = 131) were obtained at five…
Comparing Creative Thinking Abilities and Reasoning Ability of Deaf and Hearing Children
ERIC Educational Resources Information Center
Ebrahim, Fawzy
2006-01-01
This study focuses on comparing the creative thinking and reasoning abilities of deaf and hearing children. Two groups of deaf (N = 210) and hearing children (N = 200) were chosen based on specific criteria. Two instruments were used in the study: the Torrance Tests of Creative Thinking-Figural, Form A and Matrix Analogies Test. Canonical…
The Tyranny of Setting (Ability Grouping): Challenges to Inclusion in Scottish Primary Schools
ERIC Educational Resources Information Center
Hamilton, Lorna; O'Hara, Paul
2011-01-01
Debate around the use of ability grouping in schools, resonates across national boundaries as concerns rise around the possible negative impact on young people, particularly those in already disadvantaged groups. In this paper, a survey focussing on primary schools in Scotland established the extent to which some form of ability grouping has…
A Note on the Reliability Coefficients for Item Response Model-Based Ability Estimates
ERIC Educational Resources Information Center
Kim, Seonghoon
2012-01-01
Assuming item parameters on a test are known constants, the reliability coefficient for item response theory (IRT) ability estimates is defined for a population of examinees in two different ways: as (a) the product-moment correlation between ability estimates on two parallel forms of a test and (b) the squared correlation between the true…
ERIC Educational Resources Information Center
Costa, H. M.; Nicholson, B.; Donlan, C.; Van Herwegen, J.
2018-01-01
Background: Different domain-specific and domain-general cognitive precursors play a key role in the development of mathematical abilities. The contribution of these domains to mathematical ability changes during development. Primary school-aged children who show mathematical difficulties form a heterogeneous group, but it is not clear whether…
Containerless synthesis of interesting glasses
NASA Technical Reports Server (NTRS)
Weinberg, Michael C.
1990-01-01
One aspect of containerless glass experimentation was thoroughly examined: glass forming ability. It is argued that although containerless processing will abet glass formation, other ground-based methods can do the job better. However, these methods have limitations, such as sample dimensions and concomitant ability to make property measurements. Most importantly, perhaps, is the observation that glass properties are a function of preparation procedure. Thus, it seems as though there still is an argument for use of containerless processing for glass forming.
R-Ras contributes to LTP and contextual discrimination.
Darcy, M J; Jin, S-X; Feig, L A
2014-09-26
The ability to discriminate between closely related contexts is a specific form of hippocampal-dependent learning that may be impaired in certain neurodegenerative disorders such as Alzheimer's and Down Syndrome. However, signaling pathways regulating this form of learning are poorly understood. Previous studies have shown that the calcium-dependent exchange factor Ras-GRF1, an activator of Rac, Ras and R-Ras GTPases, is important for this form of learning and memory. Moreover, the ability to discriminate contexts was linked to the ability of Ras-GRF1 to promote high-frequency stimulation long-term potentiation (HFS-LTP) via the activation of p38 Map kinase. Here, we show that R-Ras is involved in this form of learning by using virally-delivered miRNAs targeting R-Ras into the CA1 region of the dorsal hippocampus and observing impaired contextual discrimination. Like the loss of GRF1, knockdown of R-Ras in the CA1 also impairs the induction of HFS-LTP and p38 Map kinase. Nevertheless, experiments indicate that this involvement of R-Ras in HFS-LTP that is required for contextual discrimination is independent of Ras-GRF1. Thus, R-Ras is a novel regulator of a form of hippocampal-dependent LTP as well as learning and memory that is affected in certain forms of neurodegenerative diseases. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.
The savant syndrome and autistic disorder.
Treffert, D A
1999-12-01
Savant syndrome, characterized by remarkable islands of mental ability in otherwise mentally handicapped persons, may occur in autistic as well as nonautistic individuals. Overall, approximately 10% of autistic persons exhibit savant abilities; roughly 50% of those with savant syndrome have autism, and the remaining 50% have other forms of developmental disability. Most commonly, savant syndrome takes the form of extraordinary musical abilities, but may also include calendar-calculation, artistic, mathematical, spatial, mechanical, and memory skills. While savant syndrome was first described more than a century ago, only recently have researchers begun to employ a more uniform nomenclature and more standardized testing in an effort to compare the abilities of savants with those of normal persons. Males show signs of savant syndrome approximately four times more often than females. Along with imaging study findings, this fact suggests the presence of a developmental disorder involving left-brain damage with right-brain compensation.
Komagoe, Keiko; Katsu, Takashi
2006-02-01
A luminol chemiluminescence method was used to evaluate the porphyrin-induced photogeneration of hydrogen peroxide (H2O2). This method enabled us to detect H202 in the presence of a high concentration of porphyrin, which was not possible using conventional colorimetry. The limit of detection was about 1 microM. We compared the ability to generate H2O2, using uroporphyrin (UP), hexacarboxylporphyrin (HCP), coproporphyrin (CP), hematoporphyrin (HP), mesoporphyrin (MP), and protoporphyrin (PP). The amount of H2O2 photoproduced was strongly related to the state of the porphyrin in the aqueous solution. UP and HCP, which existed predominantly in a monomeric form, had a good ability to produce H2O2. HP and MP, existing as dimers, showed weak activity. CP, forming a mixture of monomer and dimer, had a moderate ability to produce H2O2. PP, which was highly aggregated, had a good ability. These results demonstrated that the efficiency of porphyrins to produce H2O2 was strongly dependent on their aggregated form, and the dimer suppressed the production of H2O2.
Aslantaş, Özkan; Demir, Cemil
2016-11-01
A total of 112 Staphylococcus aureus isolates obtained from subclinical bovine mastitis cases were examined for antibiotic susceptibility and biofilm-forming ability as well as genes responsible for antibiotic resistance, biofilm-forming ability, and adhesin. Antimicrobial susceptibility of the isolates were determined by disk diffusion method. Biofilm forming ability of the isolates were investigated by Congo red agar method, standard tube method, and microplate method. The genes responsible for antibiotic resistance, biofilm-forming ability, and adhesion were examined by PCR. Five isolates (4.5%) were identified as methicillin-resistant Staph. aureus by antibiotic susceptibility testing and confirmed by mecA detection. The resistance rates to penicillin, ampicillin, tetracycline, erythromycin, trimethoprim-sulfamethoxazole, enrofloxacin, and amoxicillin-clavulanic acid were 45.5, 39.3, 33, 26.8, 5.4, 0.9, and 0.9%, respectively. All isolates were susceptible against vancomycin and gentamicin. The blaZ (100%), tetK (67.6%), and ermA (70%) genes were the most common antibiotic-resistance genes. Using Congo red agar, microplate, and standard tube methods, 70.5, 67, and 62.5% of the isolates were found to be biofilm producers, respectively. The percentage rate of icaA, icaD, and bap genes in Staph. aureus isolates were 86.6, 86.6, and 13.4%, respectively. The adhesion molecules fnbA, can, and clfA were detected in 87 (77.7%), 98 (87.5%), and 75 (70%) isolates, respectively. The results indicated that Staph. aureus from sublinical bovine mastitis cases were mainly resistant to β-lactams and, to a lesser extent, to tetracycline and erythromycin. Also, biofilm- and adhesion-related genes, which are increasingly accepted as an important virulence factor in the pathogenesis of Staph. aureus infections, were detected at a high rate. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
... next day Learn information, get insight, and form memories Give your heart and vascular system a rest ... ability to think clearly, react quickly, and form memories. This may cause you to make bad decisions ...
ERIC Educational Resources Information Center
Ree, Malcolm James; And Others
A study investigated the roles of general ability and specific abilities as predictors of several job performance criteria for Air Force enlistees in eight jobs. Subjects were 1,545 Air Force enlistees entering from 1984 through 1988 who had tested with the Armed Services Vocational Aptitude Battery (ASVAB) parallel forms 11, 12, or 13. Subjects…
Medium-range structure and glass forming ability in Zr–Cu–Al bulk metallic glasses
Zhang, Pei; Maldonis, Jason J.; Besser, M. F.; ...
2016-03-05
Fluctuation electron microscopy experiments combined with hybrid reverse Monte Carlo modeling show a correlation between medium-range structure at the nanometer scale and glass forming ability in two Zr–Cu–Al bulk metallic glass (BMG) alloys. Both Zr 50Cu 35Al 15 and Zr 50Cu 45Al 5 exhibit two nanoscale structure types, one icosahedral and the other more crystal-like. In Zr 50Cu 35Al 15, the poorer glass former, the crystal-like structure is more stable under annealing below the glass transition temperature, T g, than in Zr 50Cu 45Al 5. Variable resolution fluctuation microscopy of the MRO clusters show that in Zr 50Cu 35Al 15more » on sub-Tg annealing, the crystal-like clusters shrink even as they grow more ordered, while icosahedral-like clusters grow. Furthermore, the results suggest that achieving better glass forming ability in this alloy system may depend more on destabilizing crystal-like structures than enhancing non-crystalline structures.« less
A comparison of methods for quantifying angiogenesis in the Matrigel assay in vitro.
Khoo, Cheen Peen; Micklem, Kingsley; Watt, Suzanne M
2011-09-01
Angiogenesis is of major interest because of its involvement in numerous pathologies or for promoting tissue repair. It is often assessed by the ability of endothelial cells to sprout, migrate, and form vascular tubules in Matrigel in vitro. Matrigel contains a mixture of basement membrane components, which stimulate endothelial cells to form capillary-like hexagonal structures, and is often preferred over other in vitro assays because of its ease of use, rapidity and the ability to measure key steps in angiogenesis, including migration, protease activity, and tubule formation. Various methods have been used to quantitate tubule formation, yet no consensus has been reached regarding the best quantification method for evaluating the efficacy of angiogenic stimulants or inhibitors in this Matrigel assay. Here, we have measured the ability of umbilical cord blood endothelial colony-forming cell-derived cells to form tubules in growth factor reduced Matrigel in the presence or absence of two angiogenic inhibitors, suramin and SU6668, to compare the benefits and limitations of two quantification methods-Angiosys and Wimasis. These comparative analyses revealed that both Angiosys and Wimasis are easy to use, accurately quantify angiogenesis, and will suit the needs of different types of users. © Mary Ann Liebert, Inc.
Muadcheingka, Thaniya; Tantivitayakul, Pornpen
2015-06-01
The purposes of this investigation were to study the prevalence of Candida albicans and non-albicans Candida (NAC) species from oral candidiasis patients and evaluate the cell surface hydrophobicity (CSH) and biofilm forming capacity of the clinical isolates Candida species from oral cavity. This study identified a total of 250 Candida strains isolated from 207 oral candidiasis patients with PCR-RFLP technique. CSH value, total biomass of biofilm and biofilm forming ability of 117 oral Candida isolates were evaluated. C. albicans (61.6%) was still the predominant species in oral candidiasis patients with and without denture wearer, respectively, followed by C. glabrata (15.2%), C. tropicalis (10.4%), C. parapsilosis (3.2%), C. kefyr (3.6%), C. dubliniensis (2%), C. lusitaniae (2%), C. krusei (1.6%), and C. guilliermondii (0.4%). The proportion of mixed colonization with more than one Candida species was 18% from total cases. The relative CSH value and biofilm biomass of NAC species were greater than C. albicans (p<0.001). Ninety-two percent of oral isolates NAC species had biofilm forming ability, whereas 78% of C. albicans were biofilm formers. Furthermore, the significant difference of relative CSH values between biofilm formers and non-biofilm formers was observed in the NAC species (p<0.005), whereas the difference was not statistically significant in C. albicans. The frequency of the NAC species colonization in oral cavity was gradually increasing. The possible contributing factors might be high cell surface hydrophobicity and biofilm forming ability. The relative CSH value could be a putative factor for determining biofilm formation ability of the non-albicans Candida species. Copyright © 2015 Elsevier Ltd. All rights reserved.
Wu, Rui-Xin; Bi, Chun-Sheng; Yu, Yang; Zhang, Lin-Lin; Chen, Fa-Ming
2015-08-01
In this study, periodontal ligament (PDL) stem cells (PDLSCs) derived from different-aged donors were used to evaluate the effect of aging on cell sheet formation. The activity of PDLSCs was first determined based on their colony-forming ability, surface markers, proliferative/differentiative potentials, senescence-associated β-galactosidase (SA-βG) staining, and expression of pluripotency-associated transcription factors. The ability of these cells to form sheets, based on their extracellular matrix (ECM) contents and their functional properties necessary for osteogenic differentiation, was evaluated to predict the age-related changes in the regenerative capacity of the cell sheets in their further application. It was found that human PDLSCs could be isolated from the PDL tissue of different-aged subjects. However, the ability of the PDLSCs to proliferate and to undergo osteogenic differentiation and their expression of pluripotency-associated transcription factors displayed age-related decreases. In addition, these cells exhibited an age-related increase in SA-βG expression. Aged cells showed an impaired ability to form functional cell sheets, as determined by morphological observations and Ki-67 immunohistochemistry staining. Based on the production of ECM proteins, such as fibronectin, integrin β1, and collagen type I; alkaline phosphatase (ALP) activity; and the expression of osteogenic genes, such as ALP, Runt-related transcription factor 2, and osteocalcin, cell sheets formed by PDLSCs derived from older donors demonstrated a less potent osteogenic capacity compared to those formed by PDLSCs from younger donors. Our data suggest that the age-associated decline in the matrix contents and osteogenic properties of PDLSC sheets should be taken into account in cell sheet engineering research and clinical periodontal regenerative therapy. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Learning about Academic Ability and the College Drop-Out Decision. NBER Working Paper No. 14810
ERIC Educational Resources Information Center
Stinebrickner, Todd R.; Stinebrickner, Ralph
2009-01-01
We use unique data to examine how college students from low income families form expectations about academic ability and to examine the role that learning about ability and a variety of other factors play in the college drop-out decision. From the standpoint of satisfying a central implication from the theory of drop-out, we find that…
Education of Gifted Students in Europe
ERIC Educational Resources Information Center
Sekowski, Andrzej E.; Lubianka, Beata
2015-01-01
The present article contains a review of the literature devoted to gifted education in Europe. Forms of supporting the development of gifted students provided in European schools are presented with reference to the problems of diagnosing exceptional abilities, the existence and forms of educational measures for gifted students and forms of…
Runway image shape as a cue for judgment of approach angle.
DOT National Transportation Integrated Search
1979-11-01
One cue for visual judgment of glidepath angle has been referred to as form ratio. Form ratio is defined as the ratio of vertical height of the runway to width of the far end in the runway retinal image. The ability of pilots to judge form ratios was...
Gutierrez, J Claudio; Chigerwe, Munashe; Ilkiw, Jan E; Youngblood, Patricia; Holladay, Steven D; Srivastava, Sakti
Spatial visualization ability refers to the human cognitive ability to form, retrieve, and manipulate mental models of spatial nature. Visual reasoning ability has been linked to spatial ability. There is currently limited information about how entry-level spatial and visual reasoning abilities may predict veterinary anatomy performance or may be enhanced with progression through the veterinary anatomy content in an integrated curriculum. The present study made use of two tests that measure spatial ability and one test that measures visual reasoning ability in veterinary students: Guay's Visualization of Views Test, adapted version (GVVT), the Mental Rotations Test (MRT), and Raven's Advanced Progressive Matrices Test, short form (RavenT). The tests were given to the entering class of veterinary students during their orientation week and at week 32 in the veterinary medical curriculum. Mean score on the MRT significantly increased from 15.2 to 20.1, and on the RavenT significantly increased from 7.5 to 8.8. When females only were evaluated, results were similar to the total class outcome; however, all three tests showed significant increases in mean scores. A positive correlation between the pre- and post-test scores was found for all three tests. The present results should be considered preliminary at best for associating anatomic learning in an integrated curriculum with spatial and visual reasoning abilities. Other components of the curriculum, for instance histology or physiology, could also influence the improved spatial visualization and visual reasoning test scores at week 32.
Zhang, Erlin; Wang, Xiaoyan; Chen, Mian; Hou, Bing
2016-12-01
Ti-Cu alloys have exhibited strong antibacterial ability, but Ti-Cu alloys prepared by different processes showed different antibacterial ability. In order to reveal the controlling mechanism, Ti-Cu alloys with different existing forms of Cu element were prepared in this paper. The effects of the Cu existing form on the microstructure, mechanical, corrosion and antibacterial properties of Ti-Cu alloys have been systematically investigated. Results have shown that the as-cast Ti-Cu alloys showed a higher hardness and mechanical strength as well as a higher antibacterial rate (51-64%) but a relatively lower corrosion resistance than pure titanium. Treatment at 900°C/2h (T4) significantly increased the hardness and the strength, improved the corrosion resistance but had little effect on the antibacterial property. Treatment at 900°C/2h+400°C/12h (T6) increased further the hardness and the mechanical strength, improved the corrosion resistance and but also enhanced the antibacterial rate (>90%) significantly. It was demonstrated that the Cu element in solid solution state showed high strengthening ability but low antibacterial property while Cu element in Ti2Cu phase exhibited strong strengthening ability and strong antibacterial property. Ti2Cu phase played a key role in the antibacterial mechanism. The antibacterial ability of Ti-Cu alloy was strongly proportional to the Cu content and the surface area of Ti2Cu phase. High Cu content and fine Ti2Cu phase would contribute to a high strength and a strong antibacterial ability. Copyright © 2016 Elsevier B.V. All rights reserved.
Muslim, Sahira Nsayef; Al-Kadmy, Israa M S; Hussein, Nadheema Hammood; Mohammed Ali, Alaa Naseer; Taha, Buthainah Mohammed; Aziz, Sarah Naji; Kheraif, Abdulaziz Abdullah Al; Divakar, Darshan Devang; Ramakrishnaiah, Ravikumar
2016-11-01
A number of bacterial species produces chitosanases which has variety of applications because of its high biodegradability, non-toxicity and antimicrobial assets. In the present study chitosanase is purified from new bacterial species Bacillus licheniformis from spoiled vegetable. This novel strain of Bacillus licheniformis isolated from spoilt cucumber and pepper samples has the ability to produce the chitosanase enzyme when grown on chitosan substrate. Study also examined its antibiofilm properties against diverse bacterial species with biofilm forming ability. The purified chitosanase inhibited the biofilm formation ability for all Gram-negative and Gram-positive biofilm-forming bacteria [biofilm producers] tested in this study in congo red agar and microtiter plate's methods. Highly antibiofilm activity of chitosanase was recorded against Pseudomonas aeruginosa followed by Klebsiella pneumoniae with reduction of biofilm formation upto 22 and 29%, respectively compared with [100] % of control. Biofilm formation has multiple role including ability to enhance resistance and self-protection from external stress. This chitosanase has promising benefit as antibiofilm agent against biofilm forming pathogenic bacteria and has promising application as alternative antibiofilm agents to combat the growing number of multidrug resistant pathogen-associated infections, especially in situation where biofilms are involved. Copyright © 2016 Elsevier Ltd. All rights reserved.
Mtimet, Narjes; Guégan, Stéphanie; Durand, Lucile; Mathot, Anne-Gabrielle; Venaille, Laurent; Leguérinel, Ivan; Coroller, Louis; Couvert, Olivier
2016-05-01
Thermophilic spore-forming bacteria are potential contaminants in several industrial sectors involving high temperatures (40-65 °C) in the manufacturing process. Among those thermophilic spore-forming bacteria, Thermoanaerobacterium thermosaccharolyticum, called "the swelling canned food spoiler", has generated interest over the last decade in the food sector. The aim of this study was to investigate and to model pH effect on growth, heat resistance and recovery abilities after a heat-treatment of T. thermosaccharolyticum DSM 571. Growth and sporulation were conducted on reinforced clostridium media and liver broth respectively. The highest spore heat resistances and the greatest recovery ability after a heat-treatment were obtained at pH condition allowing maximal growth rate. Growth and sporulation boundaries were estimated, then models using growth limits as main parameters were extended to describe and quantify the effect of pH on recovery of injured spores after a heat-treatment. So, cardinal values were used as a single set of parameters to describe growth, sporulation and recovery abilities. Besides, this work suggests that T. thermosaccharolyticum preserve its ability for germination and outgrowth after a heat-treatment at a low pH where other high resistant spore-forming bacteria like Geobacillus stearothermophilus are unable to grow. Copyright © 2015 Elsevier Ltd. All rights reserved.
Marshall, Chloe R; Ramus, Franck; van der Lely, Heather
2011-10-01
English speakers have to recognize, for example, that te[m] in te[m] pens is a form of ten, despite place assimilation of the nasal consonant. Children with dyslexia and specific language impairment (SLI) are commonly proposed to have a phonological deficit, and we investigate whether that deficit extends to place assimilation, as a way of probing phonological representations and phonological grammar. Children with SLI plus dyslexia, SLI only, and dyslexia only listened to sentences containing a target word in different assimilatory contexts-viable, unviable, and no change-and pressed a button to report hearing the target. The dyslexia-only group did not differ from age-matched controls, but the SLI groups showed more limited ability to accurately identify words within sentences. Once this factor was taken into account, the groups did not differ in their ability to compensate for assimilation. The results add to a growing body of evidence that phonological representations are not necessarily impaired in dyslexia. SLI children's results suggest that they too are sensitive to this aspect of phonological grammar, but are more liberal in their acceptance of alternative phonological forms of words. Furthermore, these children's ability to reject alternative phonological forms seems to be primarily limited by their vocabulary size and phonological awareness abilities.
Katsumata, Yuriko; Mathews, Melissa; Abner, Erin L.; Jicha, Gregory A.; Caban-Holt, Allison; Smith, Charles D.; Nelson, Peter T.; Kryscio, Richard J.; Schmitt, Frederick A.; Fardo, David W.
2015-01-01
Background The Boston Naming Test (BNT) is a commonly used neuropsychological test of confrontation naming that aids in determining the presence and severity of dysnomia. Many short versions of the original 60-item test have been developed and are routinely administered in clinical/research settings. Because of the common need to translate similar measures within and across studies, it is important to evaluate the operating characteristics and agreement of different BNT versions. Methods We analyzed longitudinal data of research volunteers (n = 681) from the University of Kentucky Alzheimer’s Disease Center longitudinal cohort. Conclusions With the notable exception of the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) 15-item BNT, short forms were internally consistent and highly correlated with the full version; these measures varied by diagnosis and generally improved from normal to mild cognitive impairment (MCI) to dementia. All short forms retained the ability to discriminate between normal subjects and those with dementia. The ability to discriminate between normal and MCI subjects was less strong for the short forms than the full BNT, but they exhibited similar patterns. These results have important implications for researchers designing longitudinal studies, who must consider that the statistical properties of even closely related test forms may be quite different. PMID:25613081
Role of Candida albicans polymorphism in interactions with oral epithelial cells.
Villar, C C; Kashleva, H; Dongari-Bagtzoglou, A
2004-08-01
Candida albicans is a polymorphic organism which undergoes morphologic transition between yeast, pseudohyphal and hyphal forms. The ability of C. albicans to change from yeast to filamentous types is a major virulence determinant of this organism. However, the exact role of hyphal transformation in establishing oral mucosal infection is still poorly understood. In this study we used mutants with defects in filamentation, as well as oral strains, which differ in their capacity to form true hyphae, to examine the role of hyphal transformation in the interactions of C. albicans with oral epithelial cells in vitro. These interactions included the ability of these strains to adhere to and injure epithelial cells, as well as their ability to trigger a proinflammatory cytokine response. We found that strains SC5314 and ATCC28366 formed true hyphae on epithelial cells, whereas strain ATCC32077 and the tup1/tup1 mutant formed only pseudohyphae. Double mutant efg1/efg1cph1/cph1 grew exclusively as blastospores. We also found that yeast and pseudohyphal strains showed reduced adherence capacity to oral keratinocytes and caused minimal cell damage. Moreover, we showed that both yeast and pseudohyphal forms have a strongly attenuated proinflammatory phenotype, since they failed to induce significant interleukin (IL)-1alpha and IL-8 responses by oral epithelial cells. Germination of C. albicans into true hyphae is particularly important in the interactions with oral epithelial cells in vitro.
Simultaneous and successive cognitive processes in the Mueller-Lyer illusion.
Jarman, R F
1979-03-01
Performance in the Mueller-Lyer Illusion was analyzed for whole and partial presentations of the figure. S s were 120 third grade boys and girls. Four experimental groups were formed with the use of the human abilities model of simultaneous and successive syntheses, and the two types of presentation were given to each group. Results indicated that illusory effects in both presentations of the figure were significantly reduced by ability in simultaneous synthesis. Performance in the two presentations was also affected by successive ability, but these effects were in opposite directions for the two forms of presentation. The results did not support Piaget's theory of perceptual development, although they were consistent with the theory of simultaneous and successive syntheses. Suggestions are made for the design of future research.
New Forming Technologies for Autobody at POSCO
NASA Astrophysics Data System (ADS)
Lee, Hong-Woo; Cha, Myung-Hwan; Choi, Byung-Keun; Kim, Gyo-Sung; Park, Sung-Ho
2011-08-01
As development of car body with light weight and enhanced safety became one of the hottest issues in the auto industry, the advanced high strength steels have been broadly applied to various automotive parts over the last few years. Corresponding to this trend, POSCO has developed various types of cold and hot rolled AHSSs such as DP, TRIP, CP and FB, and continues to develop new types of steel in order to satisfy the requirement of OEMs more extensively. To provide optimal technical supports to customers, POSCO has developed more advanced EVI concept, which includes the concept of CE/SE, VA/VE, VI and PP as well as the conventional EVI strategy. To realize this concept, POSCO not only supports customers with material data, process guideline, and evaluation of formability, weld-ability, paint-ability and performance but also provides parts or sub-assemblies which demand highly advanced technologies. Especially, to accelerate adoption of AHSS in autobody, POSCO has tried to come up with optimal solutions to AHSS forming. Application of conventional forming technologies has been restricted more and more by relatively low formability of AHSS with high tensile-strength. To overcome the limitation in the forming, POSCO has recently developed new forming technologies such as hydro-forming, hot press forming, roll forming and form forming. In this paper, tailored strength HPF, hydroformed torsion beam axle and multi-directional roll forming are introduced as examples of new forming technologies.
Gelling ability and crystal morphology of sunflower wax in soybean oil
USDA-ARS?s Scientific Manuscript database
Plant waxes can effectively form organogels with vegetable oils and these organogels have drawn considerable interests as alternatives to solid fats containing trans fats and saturated fats in margarines and spreads. Among them sunflower wax showed the most pronounced gelling ability. In an attempt ...
Selective Preservation of Syntax in Alzheimer's Dementia.
ERIC Educational Resources Information Center
Kempler, Daniel; Curtiss, Susan
A study investigating the independence of linguistic abilities from each other, specifically the separability of syntax and semantics and the autonomy of syntactic abilities, is described. In the study, 30 individuals with Alzheimer's disease produced spontaneous conversations, completed sentences eliciting 16 grammatical forms, and when possible,…
Effects of Scaffolds and Scientific Reasoning Ability on Web-Based Scientific Inquiry
ERIC Educational Resources Information Center
Wu, Hui-Ling; Weng, Hsiao-Lan; She, Hsiao-Ching
2016-01-01
This study examined how background knowledge, scientific reasoning ability, and various scaffolding forms influenced students' science knowledge and scientific inquiry achievements. The students participated in an online scientific inquiry program involving such activities as generating scientific questions and drawing evidence-based conclusions,…
Organic Reaction Mechanisms in the Sixth Form Part 2.
ERIC Educational Resources Information Center
Simpson, Peter
1989-01-01
Presents the mechanistic ideas underlying reactions between nucleophiles and carbonyl compounds as well as some popular misconceptions. Relates reactions of carboxylic acid derivatives to those of aldehydes and ketones. Discusses leaving group ability and the ability of carbonyl oxygen to accept a negative charge. (Author/MVL)
Focsan, A. Ligia; Polyakov, Nikolay E.; Kispert, Lowell D.
2017-01-01
The antioxidant astaxanthin is known to accumulate in Haematococcus pluvialis algae under unfavorable environmental conditions for normal cell growth. The accumulated astaxanthin functions as a protective agent against oxidative stress damage, and tolerance to excessive reactive oxygen species (ROS) is greater in astaxanthin-rich cells. The detailed mechanisms of protection have remained elusive, however, our Electron Paramagnetic Resonance (EPR), optical and electrochemical studies on carotenoids suggest that astaxanthin’s efficiency as a protective agent could be related to its ability to form chelate complexes with metals and to be esterified, its inability to aggregate in the ester form, its high oxidation potential and the ability to form proton loss neutral radicals under high illumination in the presence of metal ions. The neutral radical species formed by deprotonation of the radical cations can be very effective quenchers of the excited states of chlorophyll under high irradiation. PMID:29065482
Hamed, Saher; Brenner, Benjamin; Aharon, Anat; Daoud, Deeb; Roguin, Ariel
2009-10-30
The function of endothelial progenitor cells (EPCs), which are key cells in vascular repair, is impaired in diabetes mellitus. Nitric oxide (NO) and reactive oxygen species can regulate EPC functions. EPCs tolerate oxidative stress by upregulating superoxide dismutase (SOD), the enzyme that neutralizes superoxide anion (O2-). Therefore, we investigated the roles of NO and SOD in glucose-stressed EPCs. The functions of circulating EPCs from patients with type 2 diabetes were compared to those from healthy individuals. Healthy EPCs were glucose-stressed, and then treated with insulin and/or SOD. We assessed O2- generation, NO production, SOD activity, and their ability to form colonies. EPCs from diabetic patients generated more O2-, had higher NAD(P)H oxidase and SOD activity, but lower NO bioavailability, and expressed higher mRNA and protein levels of p22-phox, and manganese SOD and copper/zinc SOD than those from the healthy individuals. Plasma glucose and HbA1c levels in the diabetic patients were correlated negatively with the NO production from their EPCs. SOD treatment of glucose-stressed EPCs attenuated O2- generation, restored NO production, and partially restored their ability to form colonies. Insulin treatment of glucose-stressed EPCs increased NO production, but did not change O2- generation and their ability to form colonies. However, their ability to produce NO and to form colonies was fully restored after combined SOD and insulin treatment. Our data provide evidence that SOD may play an essential role in EPCs, and emphasize the important role of antioxidant therapy in type 2 diabetic patients.
Heinemann, Allen W; Kisala, Pamela A; Hahn, Elizabeth A; Tulsky, David S
2015-05-01
To develop a spinal cord injury (SCI)-focused version of PROMIS and Neuro-QOL social domain item banks; evaluate the psychometric properties of items developed for adults with SCI; and report information to facilitate clinical and research use. We used a mixed-methods design to develop and evaluate Ability to Participate in Social Roles and Activities and Satisfaction with Social Roles and Activities items. Focus groups helped define the constructs; cognitive interviews helped revise items; and confirmatory factor analysis and item response theory methods helped calibrate item banks and evaluate differential item functioning related to demographic and injury characteristics. Five SCI Model System sites and one Veterans Administration medical center. The calibration sample consisted of 641 individuals; a reliability sample consisted of 245 individuals residing in the community. A subset of 27 Ability to Participate and 35 Satisfaction items demonstrated good measurement properties and negligible differential item functioning related to demographic and injury characteristics. The SCI-specific measures correlate strongly with the PROMIS and Neuro-QOL versions. Ten item short forms correlate >0.96 with the full banks. Variable-length CATs with a minimum of 4 items, variable-length CATs with a minimum of 8 items, fixed-length CATs of 10 items, and the 10-item short forms demonstrate construct coverage and measurement error that is comparable to the full item bank. The Ability to Participate and Satisfaction with Social Roles and Activities CATs and short forms demonstrate excellent psychometric properties and are suitable for clinical and research applications.
Teaching Students to Form Effective Questions
ERIC Educational Resources Information Center
Stafford, Tish
2009-01-01
The ability to question lies at the heart of human curiosity and is a necessary component of cognition. The author stresses that forming questions is essential to human thought and communication. As such, forming questions is a foundational process that cuts across curricular areas and is embedded in content standards across the nation, including…
ERIC Educational Resources Information Center
Khaghaninezhad, Mohammad Saber; Jafarzadeh, Ghasem
2014-01-01
Listening comprehension is usually considered as one of the most difficult language skills to EFL learners due to the unavoidable presence of "reduced forms" in authentic speech. This study was an attempt to investigate the effect of explicit "reduced forms" instruction on Iranian EFL learners' overall listening comprehension…
ERIC Educational Resources Information Center
Hansen, Kathryn Strong
2012-01-01
In the 18th century, critics grumbled about a new literary form that supposedly threatened the abilities of youth to distinguish between reality and artificiality. This form was the novel, one of the literary forms that critics now hold dearest. Currently, the graphic novel receives a great deal of criticism. Yet many teachers have shown how…
NASA Astrophysics Data System (ADS)
Single, R.; Jerram, D.; Pearson, D.; Hobbs, R.
2003-04-01
Field investigations in Skye and Namibia have provided insight into structure and architecture of CFBs. The studies have been developed into lava sequence models in 3-D software GoCad. The understanding has been applied to interpretation of lavas in the Faeroe-Shetland trough. Volcanics hinder petroleum exploration in this play due to their complex internal geometries and velocity structure. Seismic resolution is poor beneath volcanics. Fieldwork has shown that lavas on Skye have developed from (olivine-phyric) compound basalts towards the base of the sequence, into more massive flows higher up the succession. Fieldwork in the Etendeka CFBs reveal a similar style of lava field development. The focus of the offshore study is through the area of the GFA-99 seismic data. Detailed 3-D interpretation over the central data area is 20x20km in dimensions. The lava sequence present may be sub-divided vertically and laterally into 4 zones between the following seismic picks: Base basalt/sub-basalt sills, top compound lava-dominated series, top Middle Series, top hyaloclastites, top massive basalt. Within the lava sequence, the surfaces have rugose topographies. Lower zone lavas are characterised by discontinuous, indistinct reflectors. These are interpreted to be sub-aerially effused basalts with compound-braided architecture. Middle Series basalts are considered to be a combination of compound lavas and more massive, tabular flows. Steeply dipping seismic reflectors also form part of the Middle Series and are interpreted as foreset-bedded hyaloclastites. The uppermost lavas have strong reflection characteristics and are laterally extensive. These are interpreted to be massive tabular lavas covering an area >8.4 x10^3 km^2. Such flows exist in upper parts of CFB sequences as evidenced from fieldwork. Complex stacking arrangements of lavas seen in the field, and the complexities observed in seismic, suggest that many factors need to be considered within CFBs for improved sub-volcanic imaging. Factors include understanding: The facies-zones present, changes in velocity structure and the geometries present within facies types. EU 5th Framework Project SIMBA is a collaborative research project combining industrial and academic partners in flood basalt research. SIMBA incorporates: TotalFinaElf GRC, ARK Geophysics, Norsk Hydro, Institut Français du Pétrole (IFP) and Universities of Durham, Cambridge, UC Dublin and Brest.
Student teachers’ mathematical questioning and courage in metaphorical thinking learning
NASA Astrophysics Data System (ADS)
Hendriana, H.; Hidayat, W.; Ristiana, M. G.
2018-01-01
This study was designed in the form of experiments with control group design and post-test only which aimed to examine the role of metaphorical thinking learning in the mathematical questioning ability of student teachers based on the level of mathematical courage. The population of this study was student teachers of mathematics education study program in West Java Province, while the sample of this study was 152 student teachers which were set purposively and then randomly to be included in the experimental class and control class. Based on the results and discussion, it was concluded that: (a) the mathematical questioning ability of student teachers who received Metaphorical Thinking learning was better than those who received conventional learning seen from mathematical courage level; (b) learning and mathematical courage level factors affected the achievement of student teachers’ mathematical questioning ability. In addition, there was no interaction effect between learning and mathematical courage level (high, medium, and low) simultaneously in developing student teachers’ mathematical questioning ability; (c) achievement of mastering mathematical questioning ability of student teacher was still not well achieved on indicator of problem posing in the form of non-routine question and open question.
NASA Astrophysics Data System (ADS)
Saini, Manoj K.; Jin, Xiao; Wu, Tao; Liu, Yingdan; Wang, Li-Min
2018-03-01
We have investigated the enthalpic and dielectric relaxations of four groups of quinoline analogs having similar structural properties (i.e., rigidity, stiffness, and bulkiness) but a different steric character and the nature of intermolecular interactions and flexibility. The dielectric fragility index (md) and the enthalpic one (mH), determined by the Tool-Narayanaswamy-Moynihan-Hodge formalism, are comparable. Generally, for the four sets of molecules of similar structures, both the interactions and flexibility are found to be critical in making the large span of fragility (i.e., from 59 to 131) and glass forming ability. By contrast, individual impacts of the interaction and flexibility can only explain fragility partly among each group of isomers. We found that the molecules with high fragility are of relatively low liquid density, reflecting the joint impact of the interactions and flexibility. An interesting result is observed among the isomers that the molecules which are fragile have enhanced glass forming ability. The results are unveiling the joint impacts of molecular structure (flexibility) and intermolecular interaction on the molecular dynamics.
Long-term musical training may improve different forms of visual attention ability.
Rodrigues, Ana Carolina; Loureiro, Maurício Alves; Caramelli, Paulo
2013-08-01
Many studies have suggested that structural and functional cerebral neuroplastic processes result from long-term musical training, which in turn may produce cognitive differences between musicians and non-musicians. We aimed to investigate whether intensive, long-term musical practice is associated with improvements in three different forms of visual attention ability: selective, divided and sustained attention. Musicians from symphony orchestras (n=38) and non-musicians (n=38), who were comparable in age, gender and education, were submitted to three neuropsychological tests, measuring reaction time and accuracy. Musicians showed better performance relative to non-musicians on four variables of the three visual attention tests, and such an advantage could not solely be explained by better sensorimotor integration. Moreover, in the group of musicians, significant correlations were observed between the age at the commencement of musical studies and reaction time in all visual attention tests. The results suggest that musicians present augmented ability in different forms of visual attention, thus illustrating the possible cognitive benefits of long-term musical training. Copyright © 2013 Elsevier Inc. All rights reserved.
Martin, Francis L; Semple, Kirk T
2004-09-01
Speakers: John Ashby (Syngenta CTL, UK), Peter A. Behnisch (Eurofins GfA, Germany), Paul L. Carmichael (Unilever Colworth, UK), Curtis C.Harris (National Cancer Institute, USA), Kevin C. Jones (Lancaster University, UK), Andreas Kortenkamp (School of Pharmacy, London, UK), Caroline J. Langdon (Reading University, UK), Anthony M. Lynch (GlaxoSmithKline, UK), Francis L. Martin (Lancaster University, UK), Trevor J. McMillan (Lancaster University, UK), David H. Phillips (Institute of Cancer Research, UK), Huw J. Ricketts (University of Cardiff, UK), Michael N. Routledge (University of Leeds, UK), J. Thomas Sanderson (Utrecht University, The Netherlands) and Kirk T. Semple (Lancaster University, UK) The effects of many environmental exposures to either single contaminants or to mixtures still remain to be properly assessed in ecotoxicological and human toxicological settings. Such assessments need to be carried out using relevant biological assays. On a mechanistic basis, future studies need to be able to extrapolate exposure to disease risk. It is envisaged that such an approach would lead to the development of appropriate strategies to either reduce exposures or to initiate preventative measures in susceptible individuals or populations. To mark the opening of a new Institute, the Lancaster Environmental Centre, an environmental health workshop was held over 2 days (9-10 September 2003) at Lancaster University, UK. The fate, behaviour and movement of chemicals in the environment, together with environmental exposures and human health, biomarkers of such exposures, hormone-like compounds and appropriate genetic toxicology methodologies, were discussed.
The Impact of Planned Preemptive Focus on Form on Iranian EFL Learners' Essay Writing Ability
ERIC Educational Resources Information Center
Gholami, Javad; Aliyari, Somayeh
2015-01-01
Focus on Form (FonF) instruction places dual emphasis on meaningful interaction and overt reference to problematic or more complex forms in L2 classes. One way to draw attention to such forms is through incidental preemptive FonF. As an attempt to expand the scope of teacher-initiated preemptive FonF, the present quasi-experimental study explored…
Miyata, Noboru; Fuke, Ken-ichi; Chen, Qi; Kawashita, Masakazu; Kokubo, Tadashi; Nakamura, Takashi
2004-01-01
Hydrolysis and polycondensation of triethoxysilane end-capped Poly (tetramethylene oxide) (Si-PTMO), tetraethoxysilane (TEOS), tetraisopropyltitanate (TiPT) and calcium nitrate (Ca(NO(3))(2)) gave transparent monolithics of PTMO-modified CaO-SiO(2)-TiO(2) hybrids. The samples with (TiPT)/(TEOS+TiPT) molar ratios from 0 to 0.20 under constant ratio of (Si-PTMO)/(TEOS+TiPT) of 2/3 in weight were prepared. It was found that the incorporation of TiO(2) component into a PTMO-CaO-SiO(2) hybrid results in an increase in the apatite-forming ability in a simulated body fluid: the hybrids with (TiPT)/(TEOS+TiPT) of 0.10 and 0.20 in mol formed an apatite on their surfaces within only 0.5 day. It seemed that, within the range of compositions studied, the TiO(2) content little affects the overall mechanical properties: Young's modulus were 52-55MPa, tensile strength, 7-9MPa, and strain at failure, about 30%. Thus, the organic-inorganic hybrids exhibiting both fairly high apatite-forming ability and high capability for deformation were obtained. These hybrid materials may be useful as new kind of bioactive bone-repairing materials.
Barber, Sarah J.
2017-01-01
“Stereotype threat” is often thought of as a singular construct, with moderators and mechanisms that are stable across groups and domains. However, this is not always true. To illustrate this, the current review focuses on the stereotype threat that older adults face about their cognitive abilities. Using Shapiro and Neuberg's (2007) Multi-Threat Framework, I first provide evidence that this is a self-concept threat, and not a group-reputation threat. Because this differs from the form(s) of threat experienced by other groups (e.g., the threat that minority students face about their intellectual abilities), the moderators of threat observed in other groups (i.e., group identification) do not always generalize to age-based stereotype threat about cognitive decline. Looking beyond the form(s) of threat elicited, this review also provides evidence that the mechanisms underlying stereotype threat effects may vary across the lifespan. Due to age-related improvements in emotion regulation abilities, stereotype threat does not seem to reduce older adults' executive control resources. Overall, this review highlights the need to approach the concept of stereotype threat with more granularity. This will allow us to design more effective stereotype threat interventions. It will also shed light on why certain effects “fail to replicate” across domains or groups. PMID:28073332
D'Urzo, Nunzia; Pezzicoli, Alfredo; De Cesare, Virginia; Pinto, Vittoria; Margarit, Immaculada; Telford, John Laird; Maione, Domenico
2014-01-01
Streptococcus agalactiae, also known as group B Streptococcus (GBS), is a primary colonizer of the anogenital mucosa of up to 40% of healthy women and an important cause of invasive neonatal infections worldwide. Among the 10 known capsular serotypes, GBS type III accounts for 30 to 76% of the cases of neonatal meningitis. In recent years, the ability of GBS to form biofilm attracted attention for its possible role in fitness and virulence. Here, a new in vitro biofilm formation protocol was developed to guarantee more stringent conditions, to better discriminate between strong-, low-, and non-biofilm-forming strains, and to facilitate interpretation of data. This protocol was used to screen the biofilm-forming abilities of 366 GBS clinical isolates from pregnant women and from neonatal infections of different serotypes in relation to medium composition and pH. The results identified a subset of isolates of serotypes III and V that formed strong biofilms under acidic conditions. Importantly, the best biofilm formers belonged to serotype III hypervirulent clone ST-17. Moreover, the abilities of proteinase K to strongly inhibit biofilm formation and to disaggregate mature biofilms suggested that proteins play an essential role in promoting GBS biofilm initiation and contribute to biofilm structural stability. PMID:24487536
Verbal Ability, Argument Order, and Attitude Formation
Mozuraitis, Mindaugas; Chambers, Craig G.; Daneman, Meredyth
2016-01-01
The current study explored the interaction of verbal ability and presentation order on readers’ attitude formation when presented with two-sided arguments. Participants read arguments for and against compulsory voting and genetic engineering, and attitudes were assessed before and after reading the passages. Participants’ verbal ability was measured, combining vocabulary knowledge and reading comprehension skill. Results suggested that low verbal-ability participants were more persuaded by the most recent set of arguments whereas high verbal-ability participants formed attitudes independent of presentation order. Contrary to previous literature, individual differences in the personality trait need for cognition did not interact with presentation order. The results suggest that verbal ability is an important moderator of the effect of presentation order when formulating opinions from complex prose. PMID:27703437
NASA Astrophysics Data System (ADS)
Dietz, Hansjörg; Steinlein, Thomas; Ullmann, Isolde
1998-02-01
The competitive abilities of six perennial ruderal plants of three different growth forms were compared via yield measures using an additive diallel experimental design with unbalanced mixtures (9:3 or 3:9 plants per pot, respectively). Thus, in a given mixture species A was grown in two configurations: three individuals in centre position of the pot together with nine plants of species B in border position and vice versa. Effect competitive abilities as well as response competitive abilities of the species were significantly related to canopy height and plant biomass. The species with lower rosette growth form and smaller biomasses were weaker competitors than the species possessing elevated canopies along with higher biomasses, whereas total leaf area was not significantly correlated with competitive ability between species. Species differences in competitive ability were stronger between the plants grown in the central position than between those grown in the border position. Furthermore, interactions between species-specific traits and configuration could be observed, indicating the importance of species proportions and arrangement patterns for evaluation of competitive outcome in the field. The degree of complete transitivity of the competitive network of the six ruderal species, which was significantly higher than expected under the null model in our experimental design, also seemed to depend on species proportions in mixture. Shifts in root:shoot ratio of the centre plants when faced with competition by the border plants were in the direction of higher shoot allocation for the weak competitors with rosette growth form irrespective of the neighbour species, except for Bunias orientalis, which showed a more plastic response. The stronger competitors showed higher root allocation ( Urtica dioica) or were hardly affected at all. Consistent with the results of our experiment, the weaker competitors occur at rather frequently disturbed and therefore transient field sites whereas the stronger competitors predominate at infrequently disturbed sites during several phases of succession.
Pedagogical Management of University Students' Communication Ability Development
ERIC Educational Resources Information Center
Anatolievna, Spirchagova Tatiana; Munirovna, Nasyrova Albina; Kasimovna, Vakhitova Dilyara; Mirzayanovna, Sadrieva Liliya; Anatolievna, Brodskaya Tatiana
2017-01-01
The development of social interaction forms emphasizes urgency and importance of the topic. The purpose of the study is to find out peculiarities of pedagogical management of university students' communication ability development. The leading approach to the research was the narrative approach which allows considering pedagogical management of…
A Longitudinal Study of Accounting Students' Ethical Judgement Making Ability
ERIC Educational Resources Information Center
Mohamed Saat, Maisarah; Porter, Stacey; Woodbine, Gordon
2012-01-01
This paper reports the effect of a moral education programme on the ethical judgement making ability of university students. The programme comprises two forms of intervention: a dedicated ethics course and subsequent practical training. A total of 113 accounting students from six Malaysian universities participated in a longitudinal study…
The Power of Stories: Facilitating Social Communication in Children with Limited Language Abilities
ERIC Educational Resources Information Center
Brinton, Bonnie; Fujiki, Martin
2017-01-01
Children with limited language expression and comprehension abilities are at risk for academic failure, particularly in literacy acquisition. In addition, these children often have poor social outcomes, including difficulty forming friendships, social exclusion, withdrawal, and victimization. The academic and social difficulties that these…
ERIC Educational Resources Information Center
Kiperman, Sarah; Black, Mary S.; McGill, Tia M.; Harrell-Williams, Leigh M.; Kamphaus, Randy W.
2014-01-01
This study assesses the ability of a brief screening form, the Behavioral and Emotional Screening System-Student Form (BESS-SF), to predict scores on the much longer form from which it was derived: the Behavior Assessment System for Children-Second Edition Self-Report of Personality-Child Form (BASC-2-SRP-C). The present study replicates a former…
Cultural Differences in Color/Form Preference and in Classificatory Behavior
ERIC Educational Resources Information Center
Schmidt, W. H. O.; Nzimande, A.
1970-01-01
Cross-cultural data was collected on color/form preference and the ability to classify among Zulu children and adults. Significant differences were found attributable to factors of Western-type schooling, literacy, and urban or rural life. (NH)
Lan, Si; Wei, Xiaoya; Zhou, Jie; ...
2014-11-18
In-situ transmission electron microcopy and time-resolved neutron diffraction were used to study crystallization kinetics of two ternary bulk metallic glasses during isothermal annealing in the supercooled liquid region. It is found that the crystallization of Zr 56Cu 36Al 8, an average glass former, follows continuous nucleation and growth, while that of Zr 46Cu 46Al 8, a better glass former, is characterized by site-saturated nucleation, followed by slow growth. Possible mechanisms for the observed differences and the relationship to the glass forming ability are discussed.
Variant forms of ataxia telangiectasia.
Taylor, A M; Flude, E; Laher, B; Stacey, M; McKay, E; Watt, J; Green, S H; Harding, A E
1987-01-01
Two ataxia telangiectasia patients with unusual clinical and cellular features are described. Cultured fibroblasts and PHA stimulated lymphocytes from these two patients showed a smaller increase of radiosensitivity than cells from other A-T patients, as measured by colony forming ability or induced chromosome damage respectively, after exposure to ionising radiation. The response of DNA synthesis to irradiation of these cells was, however, the same as for other A-T patients. Cells from a third patient with some clinical features of A-T but with a very protracted course also showed low levels of radiation induced chromosome damage, but colony forming ability and the response of DNA synthesis after irradiation were no different from cells of normal subjects. There was, however, an increased level of translocations and unstable chromosomal rearrangements in this patient's lymphocytes. Images PMID:3430541
Usability Testing of the Indiana University Education Faculty Web Forms.
ERIC Educational Resources Information Center
Tuzun, Hakan; Lee, Sun Myung; Graham, Charles; Sluder, Kirk Job
The usability test team examined design problems that limit the ability of instructors at the Indiana University to use data entry forms on the School of Education Web site. The forms permit instructors to publish information about themselves and about courses they teach on the School of Education Web site. Faculty and graduate student instructors…
A Comparison of Six MMPI Short Forms: Code Type Correspondence and Indices of Psychopathology.
ERIC Educational Resources Information Center
Willcockson, James C.; And Others
1983-01-01
Compared six Minnesota Multiphasic Personality Inventory (MMPI) short forms with the full-length MMPI for ability to identify code-types and indices of psychopathology in renal dialysis patients (N=53) and paranoid schizophrenics (N=58). Results suggested that the accuracy of the short forms fluctuates for different patient populations and…
ERIC Educational Resources Information Center
Blevins, Dean G.
2007-01-01
Storytellers know that stories are "formed" in their telling. Stories, whether oral or written, personal or mass communicated, ultimately express the boundaries of their medium (their "embodiment" through mediated forms). Religious Educators must always address the medium as well as the message in any theory of narrative accounting. Media often…
Gordon, Katherine R; McGregor, Karla K; Waldier, Brigitte; Curran, Maura K; Gomez, Rebecca L; Samuelson, Larissa K
2016-01-01
Research on word learning has focused on children's ability to identify a target object when given the word form after a minimal number of exposures to novel word-object pairings. However, relatively little research has focused on children's ability to retrieve the word form when given the target object. The exceptions involve asking children to recall and produce forms, and children typically perform near floor on these measures. In the current study, 3- to 5-year-old children were administered a novel test of word form that allowed for recognition memory and manual responses. Specifically, when asked to label a previously trained object, children were given three forms to choose from: the target, a minimally different form, and a maximally different form. Children demonstrated memory for word forms at three post-training delays: 10 mins (short-term), 2-3 days (long-term), and 6 months to 1 year (very long-term). However, children performed worse at the very long-term delay than the other time points, and the length of the very long-term delay was negatively related to performance. When in error, children were no more likely to select the minimally different form than the maximally different form at all time points. Overall, these results suggest that children remember word forms that are linked to objects over extended post-training intervals, but that their memory for the forms gradually decreases over time without further exposures. Furthermore, memory traces for word forms do not become less phonologically specific over time; rather children either identify the correct form, or they perform at chance.
Temporary Employment Contracts in Academia: A Real Option View
ERIC Educational Resources Information Center
Brady, Malcolm
2017-01-01
This paper examines the strategic use of temporary employment contracts in dealing with supply uncertainty in the form of employee ability that is slow to reveal itself, for example in academia where there exist significant time lags in demonstration of research ability. A temporary contract is modeled as a real option, specifically as a…
Demographic Factors, Personality, and Ability as Predictors of Learning Approaches
ERIC Educational Resources Information Center
Xie, Qiuzhi; Zhang, Li-fang
2015-01-01
This study investigated the extent to which learning approaches can be accounted for by personal factors (i.e., demographics, ability, and personality). The participants were 443 students in a university in mainland China. The Revised Two-factor Study Process Questionnaire, the NEO Five-Factor Inventory-3, and the short form of Raven's Advanced…
ERIC Educational Resources Information Center
Arendasy, Martin E.; Sommer, Markus
2013-01-01
Allowing respondents to retake a cognitive ability test has shown to increase their test scores. Several theoretical models have been proposed to explain this effect, which make distinct assumptions regarding the measurement invariance of psychometric tests across test administration sessions with regard to narrower cognitive abilities and general…
Instructional Efficacy of Portfolio for Assessing Iranian EFL Learners' Speaking Ability
ERIC Educational Resources Information Center
Safari, Mahshad; Koosha, Mansour
2016-01-01
Regarding the fundamental role of speaking in language skills, this study intended to investigate the effects of speaking portfolio as an alternative form of assessment for assessing Iranian EFL learners' speaking ability at the intermediate and advanced proficiency levels and also its impact on their attitudes. Accordingly, from the population of…
The Development of Future Technology Teachers' Artistic-Projective Abilities: Foreign Experience
ERIC Educational Resources Information Center
Kurach, Mykola
2016-01-01
The necessity to form and develop future technology teachers' creative abilities has been stressed in the article. The psychologic-pedagogical researches of the leading specialists from Europe, the USA and Japan in the field of creative work and creativity have been analyzed. The main problems of the creative artistic-projective abilities…
Naming Giftedness: Whiteness and Ability Discourse in US Schools
ERIC Educational Resources Information Center
Stark, Lauren
2014-01-01
This paper offers a conceptual analysis of ability discourse using the theoretical lens of critical whiteness studies and the methodological framework of critical discourse analysis. From its origins in the Progressive Era to contemporary debates on tracking, the concept of giftedness has been formed through racial projects throughout US history.…
Cortical Bases of Elementary Deductive Reasoning: Inference, Memory, and Metadeduction
ERIC Educational Resources Information Center
Reverberi, Carlo; Shallice, Tim; D'Agostini, Serena; Skrap, Miran; Bonatti, Luca L.
2009-01-01
Elementary deduction is the ability of unreflectively drawing conclusions from explicit or implicit premises, on the basis of their logical forms. This ability is involved in many aspects of human cognition and interactions. To date, limited evidence exists on its cortical bases. We propose a model of elementary deduction in which logical…
ERIC Educational Resources Information Center
Rasiman
2015-01-01
This research aims to determine the leveling of critical thinking abilities of students of mathematics education in mathematical problem solving. It includes qualitative-explorative study that was conducted at University of PGRI Semarang. The generated data in the form of information obtained problem solving question and interview guides. The…
Comparative Effects of Ability and Feedback Form in Computer-Assisted Instruction.
ERIC Educational Resources Information Center
Clariana, Roy B.; Smith, Lana J.
A study involving 50 experimental and 99 control subjects (graduate education majors) was undertaken to assess the interchangeability of knowledge of correct response feedback (KRC) and answer until correct feedback (AUC) in computer-assisted instruction. P. L. Smith's model (1988) suggests that AUC in better for high-ability students. W. Dick and…
Early College Entrance: How Will My Child Do?
ERIC Educational Resources Information Center
Chung, Rachel U.; Hertzog, Nancy B.
2014-01-01
Early college entrance is a form of acceleration, or the process of advancing students in academic programs faster than their same-aged peers. Many early entrants have demonstrated academic ability to achieve at high levels but they exhibit tremendous variety in their age, specific abilities, social and emotional maturity, family support, and…
Connoisseurship Evaluation in Digital Painting among Art Teachers in Malaysian Secondary School
ERIC Educational Resources Information Center
Samah, Azimah A.; Hussin, Zaharah; Putih, Abu Talib
2016-01-01
Connoisseurship evaluation is a form of evaluation and educational inquiry having qualitative characteristics. In this study, these skills are seen among Malaysian art teachers in secondary schools. Quality assessment depends on the evaluator who has the ability of some aspects. Among these are qualitative nuances experiences as well as ability to…
ERIC Educational Resources Information Center
Flowers, Arthur; Crandell, Edwin W.
Three auditory perceptual processes (resistance to distortion, selective listening in the form of auditory dedifferentiation, and binaural synthesis) were evaluated by five assessment techniques: (1) low pass filtered speech, (2) accelerated speech, (3) competing messages, (4) accelerated plus competing messages, and (5) binaural synthesis.…
Adaptation and Assessment of a Public Speaking Rating Scale
ERIC Educational Resources Information Center
Iberri-Shea, Gina
2017-01-01
Prominent spoken language assessments such as the Oral Proficiency Interview and the Test of Spoken English have been primarily concerned with speaking ability as it relates to conversation. This paper looks at an additional aspect of spoken language ability, namely public speaking. This study used an adapted form of a public speaking rating scale…
ERIC Educational Resources Information Center
Chantoem, Rewadee; Rattanavich, Saowalak
2016-01-01
This research compares the English language achievements of vocational students, their reading and writing abilities, and their attitudes towards learning English taught with just-in-time teaching techniques through web technologies and conventional methods. The experimental and control groups were formed, a randomized true control group…
Deficits in Social Attribution Ability in Prader-Willi Syndrome
ERIC Educational Resources Information Center
Koenig, Kathleen; Klin, Ami; Schultz, Robert
2004-01-01
Prader-Willi syndrome (PWS), a genetic form of mental retardation, involves a myriad of physical and behavioral problems. Poor social adjustment has been reported, but the origin of this difficulty is unknown. The Social Attribution Task, a measure of one's ability to make appropriate social attributions from an ambiguous visual display [Klin…
Pazos, Ileana M; Gai, Feng
2012-10-18
While the thermodynamic effects of trimethylamine oxide (TMAO), urea, and guanidine hydrochloride (GdnHCl) on protein stability are well understood, the underlying mechanisms of action are less well characterized and, in some cases, even under debate. Herein, we employ the stretching vibration of two infrared (IR) reporters, i.e., nitrile (C≡N) and carbonyl (C═O), to directly probe how these cosolvents mediate the ability of water to form hydrogen bonds with the solute of interest, e.g., a peptide. Our results show that these three agents, despite having different effects on protein stability, all act to decrease the strength of the hydrogen bonds formed between water and the infrared probe. While the behavior of TMAO appears to be consistent with its protein-protecting ability, those of urea and GdnHCl are inconsistent with their role as protein denaturants. The latter is of particular interest as it provides strong evidence indicating that although urea and GdnHCl can perturb the hydrogen-bonding property of water their protein-denaturing ability does not arise from a simple indirect mechanism.
Reciprocal Inhibitory Interactions Between the Reward-Related Effects of Leptin and Cocaine.
You, Zhi-Bing; Wang, Bin; Liu, Qing-Rong; Wu, Yan; Otvos, Laszlo; Wise, Roy A
2016-03-01
Cocaine is habit-forming because of its ability to enhance dopaminergic neurotransmission in the forebrain. In addition to neuronal inputs, forebrain dopamine circuits are modulated by hormonal influences; one of these is leptin, an adipose-derived hormone that attenuates the rewarding effects of food- and hunger-associated brain stimulation reward. Here we report reciprocal inhibition between the reward-related effects of leptin and the reward-related effects of cocaine in rats. First, we report that cocaine and the expectancy of cocaine each depresses plasma leptin levels. Second, we report that exogenous leptin, given systemically or directly into the ventral tegmental area, attenuates the ability of cocaine to elevate dopamine levels in the nucleus accumbens, the ability of cocaine to establish a conditioned place preference, and the ability of cocaine-predictive stimuli to prolong responding in extinction of cocaine-seeking. Thus, whereas leptin represents an endogenous antagonist of the habit-forming and habit-sustaining effects of cocaine, this antagonism is attenuated by cocaine and comes to be attenuated by the expectancy of cocaine.
Hamed, Saher; Brenner, Benjamin; Aharon, Anat; Daoud, Deeb; Roguin, Ariel
2009-01-01
Background The function of endothelial progenitor cells (EPCs), which are key cells in vascular repair, is impaired in diabetes mellitus. Nitric oxide (NO) and reactive oxygen species can regulate EPC functions. EPCs tolerate oxidative stress by upregulating superoxide dismutase (SOD), the enzyme that neutralizes superoxide anion (O2-). Therefore, we investigated the roles of NO and SOD in glucose-stressed EPCs. Methods The functions of circulating EPCs from patients with type 2 diabetes were compared to those from healthy individuals. Healthy EPCs were glucose-stressed, and then treated with insulin and/or SOD. We assessed O2- generation, NO production, SOD activity, and their ability to form colonies. Results EPCs from diabetic patients generated more O2-, had higher NAD(P)H oxidase and SOD activity, but lower NO bioavailability, and expressed higher mRNA and protein levels of p22-phox, and manganese SOD and copper/zinc SOD than those from the healthy individuals. Plasma glucose and HbA1c levels in the diabetic patients were correlated negatively with the NO production from their EPCs. SOD treatment of glucose-stressed EPCs attenuated O2- generation, restored NO production, and partially restored their ability to form colonies. Insulin treatment of glucose-stressed EPCs increased NO production, but did not change O2- generation and their ability to form colonies. However, their ability to produce NO and to form colonies was fully restored after combined SOD and insulin treatment. Conclusion Our data provide evidence that SOD may play an essential role in EPCs, and emphasize the important role of antioxidant therapy in type 2 diabetic patients. PMID:19878539
Ni, Siyu; Li, Xiaohong; Yang, Pengan; Ni, Shirong; Hong, Feng; Webster, Thomas J
2016-01-01
In this study, to provide porous anodic alumina (PAA) with bioactivity and anti-bacterial properties, sol-gel derived bioactive CaO-SiO2-Ag2O materials were loaded onto and into PAA nano-pores (termed CaO-SiO2-Ag2O/PAA) by a sol-dipping method and subsequent calcination of the gel-glasses. The in vitro apatite-forming ability of the CaO-SiO2-Ag2O/PAA specimens was evaluated by soaking them in simulated body fluid (SBF). The surface microstructure and chemical property before and after soaking in SBF were characterized. Release of ions into the SBF was also measured. In addition, the antibacterial properties of the samples were tested against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The results showed that CaO-SiO2-Ag2O bioactive materials were successfully decorated onto and into PAA nano-pores. In vitro SBF experiments revealed that the CaO-SiO2-Ag2O/PAA specimens dramatically enhanced the apatite-forming ability of PAA in SBF and Ca, Si and Ag ions were released from the samples in a sustained and slow manner. Importantly, E. coli and S. aureus were both killed on the CaO-SiO2-Ag2O/PAA (by 100%) samples compared to PAA controls after 3 days of culture. In summary, this study demonstrated that the CaO-SiO2-Ag2O/PAA samples possess good apatite-forming ability and high antibacterial activity causing it to be a promising bioactive coating candidate for implant materials for orthopedic applications. Copyright © 2015 Elsevier B.V. All rights reserved.
García-Linares, Sara; Rivera-de-Torre, Esperanza; Morante, Koldo; Tsumoto, Kouhei; Caaveiro, Jose M M; Gavilanes, José G; Slotte, J Peter; Martínez-Del-Pozo, Álvaro
2016-12-06
Sea anemone actinoporins constitute a protein family of multigene pore-forming toxins (PFT). Equinatoxin II (EqtII), fragaceatoxin C (FraC), and sticholysins I and II (StnI and StnII, respectively), produced by three different sea anemone species, are the only actinoporins whose molecular structures have been studied in depth. These four proteins show high sequence identities and practically coincident three-dimensional structures. However, their pore-forming activity can be quite different depending on the model lipid system employed, a feature that has not been systematically studied before. Therefore, the aim of this work was to evaluate and compare the influence of several distinct membrane conditions on their particular pore-forming behavior. Using a complex model membrane system, such as sheep erythrocytes, StnII showed hemolytic activity much higher than those of the other three actinoporins studied. In lipid model systems, pore-forming ability when assayed against 4:1 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)/sphingomyelin (SM) vesicles, with the membrane binding being the rate-limiting step, decreased in the following order: StnI > StnII > EqtII > FraC. When using 1:1:1 DOPC/SM/cholesterol LUVs, the presence of Chol not only enhanced membrane binding affinities by ∼2 orders of magnitude but also revealed how StnII was much faster than the other three actinoporins in producing calcein release. This ability agrees with the proposal that explains this behavior in terms of their high sequence variability along their first 30 N-terminal residues. The influence of interfacial hydrogen bonding in SM- or dihydro-SM-containing bilayers was also shown to be a generalized feature of the four actinoporins studied. It is finally hypothesized that this observed variable ability could be explained as a consequence of their distinct specificities and/or membrane binding affinities. Eventually, this behavior can be modulated by the nature of their natural target membranes or the interaction with not yet characterized isotoxin forms from the same sea anemone species.
Prosthetic Rasa: Dance on Wheels and Challenged Kinesthetics
ERIC Educational Resources Information Center
Vimal C., Akhila
2017-01-01
This paper analyses "Bharatanatyam on Wheels" by Ability Unlimited Foundation, Delhi. It interrogates the possibilities and challenges that disability performance presents to codifications in the form and grammar of "Bharatanatyam," a "classical" dance form of India. The Indian classical scriptures of performance…
Industrial grade versus scientific pure: Influence on melt properties
NASA Astrophysics Data System (ADS)
Jonas, I.; Hembree, W.; Yang, F.; Busch, R.; Meyer, A.
2018-04-01
Viscosity, density, and the undercooling ability of the Zr-based bulk glass forming melt, which was manufactured in two different degrees of purity, have been studied. Investigations have been carried out by means of Couette rheometry and electrostatic and electromagnetic levitation with the latter under microgravity conditions. We found that oxygen and impurities present in industrial grade metals do not significantly alter the melt viscosity and density, while they clearly affect the undercooling ability. Comparing container based and containerless results showed that Couette rheometry can be applied in the temperature range between 1150 K and 1375 K, where it provides reliable data, but only at a rather low oxygen content. Higher oxygen contents, as in the case of the industrial grade alloy, cause measurement artefacts. In the case of Zr59.3Cu28.8Al10.4Nb1.5 alloys, these findings allow a better localization of the key factors dominating the glass forming ability.
A structural model for surface-enhanced stabilization in some metallic glass formers
NASA Astrophysics Data System (ADS)
Levchenko, Elena V.; Evteev, Alexander V.; Yavari, Alain R.; Louzguine-Luzgin, Dmitri V.; Belova, Irina V.; Murch, Graeme E.
2013-01-01
A structural model for surface-enhanced stabilization in some metallic glass formers is proposed. In this model, the alloy surface structure is represented by five-layer Kagomé-net-based lateral ordering. Such surface structure has intrinsic abilities to stabilize icosahedral-like short-range order in the bulk, acting as 'a cloak of liquidity'. In particular, recent experimental observations of surface-induced lateral ordering and a very high glass forming ability of the liquid alloy Au49Ag5.5Pd2.3Cu26.9Si16.3 can be united using this structural model. This model may be useful for the interpretation of surface structure of other liquid alloys with a high glass forming ability. In addition, it suggests the possibility of guiding the design of the surface coating of solid containers for the stabilization of undercooled liquids.
Saarni, S I; Saarni, E S; Saarni, H
2008-02-01
Self employment is increasing but it is not yet known how its different forms affect health, quality of life, and work ability. We compared the work ability, subjective quality of life (QoL), and health-related quality of life (HRQoL) of entrepreneurs both with and without personnel, farmers, and salaried workers. We investigated which domains of HRQoL are associated with work status. A nationally representative general population sample comprising 5834 Finns aged between 30 and 64. Work ability was measured using the work ability index (WAI), HRQoL using 15D and EQ-5D, and QoL with self reported global quality of life. Entrepreneurs with personnel had better work ability than salary earners, but there were no differences in QoL or HRQoL between the entrepreneurs and salary earners. Farmers scored lowest on all measures; this finding remained even after adjusting for age, sex, marital status, education, and chronic conditions. The low WAI score of farmers was mainly explained by poor subjective work ability, while their low 15D score was mainly the result of poor functioning in the psychosocial domains of HRQoL. The low EQ-5D score of farmers was explained by problems with mobility, usual activities, and with pain or discomfort. Farmers have poorer work ability, QoL, and HRQoL than other working groups, but this does not appear to be caused by physical health problems. From a research point of view, farmers should be categorised separately from other forms of entrepreneurship. From a public health point of view, improving farmers' wellbeing may require psychosocial interventions exceeding traditional health promotion.
Fabrication of topical metered dose film forming sprays for pain management.
Ranade, Sneha; Bajaj, Amrita; Londhe, Vaishali; Babul, Najib; Kao, Danny
2017-03-30
Topical film-forming metered dose spray formulations were designed for management of pain. Ropivacaine, a local anesthetic is explored for its topical efficacy in alleviating pain. Metered dose spray containers, organic solvents, film forming polymers and permeation enhancers were utilized to fabricate the Metered Dose topical spray. Factors like viscosity, spray pattern, spray angle, volume of actuation, droplet size distribution of the metered dose spray formulation and drying time, flexibility and wash-ability of the film formed after spraying were assessed. Permeation of the drug into the porcine skin was observed based on ex-vivo diffusion studies and confocal microscopy. The results indicated a high level of drug concentration in the skin layers. Anti-nociceptive efficacy of the formulations was assessed on Wistar rats by hot plate and tail flick tests, based on the response to pain perception. The results were comparable to the conventional lidocaine gel. Topical film forming sprays have the ability to provide an accurate, long lasting and patient compliant delivery of drugs on the skin as compared to conventional gels. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Ghormade, Vandana; Deshpande, M. V.
The ability of dimorphism in fungi is conventionally regarded as a reversible change between the two vegetative forms, yeast and mycelium, in response to environmental change. A zygomycetous isolate, Benjaminiella poitrasii, exhibited yeast-mycelium transition in response to the change in temperature (37-28 °C) and decrease in glucose concentration. For the first time the presence of dimorphic response during asexual and sexual spore germination is reported under the dimorphism-triggering conditions in B. poitrasii. The zygospores germinated into budding yeast when subjected to yeast-form supporting conditions. The mycelium-form favoring conditions gave rise to true mycelium. Similarly, the asexual spores displayed a dimorphic response during germination. Our observations suggest that dimorphism is an intrinsic ability present in the vegetative, asexual, and sexual forms of the fungus. As dimorphic fungi are intermediate to the unicellular yeast and the filamentous forms, understanding of the dimorphic character could be useful to trace the evolutionary relationships among taxonomically different fungi. Moreover, the implications of spore germination during the onset of pathogenesis and in drug development for human health care are discussed.
Kalsum, Sadaf; Braian, Clara; Koeken, Valerie A C M; Raffetseder, Johanna; Lindroth, Margaretha; van Crevel, Reinout; Lerm, Maria
2017-01-01
The causative agent of tuberculosis, Mycobacterium tuberculosis , shares several characteristics with organisms that produce biofilms during infections. One of these is the ability to form tight bundles also known as cords. However, little is known of the physiological relevance of the cording phenotype. In this study, we investigated whether cord-forming M. tuberculosis induce the formation of macrophage extracellular traps (METs) in human monocyte-derived macrophages. Macrophages have previously been shown to produce extracellular traps in response to various stimuli. We optimized bacterial culturing conditions that favored the formation of the cord-forming phenotype as verified by scanning electron microscopy. Microscopy analysis of METs formation during experimental infection of macrophages with M. tuberculosis revealed that cord-forming M. tuberculosis induced significantly more METs compared to the non-cording phenotype. Deletion of early secreted antigenic target-6 which is an important virulence factor of M. tuberculosis , abrogated the ability of the bacteria to induce METs. The release of extracellular DNA from host cells during infection may represent a defense mechanism against pathogens that are difficult to internalize, including cord-forming M. tuberculosis .
[Susceptibility to antifungal agents of Candida sp. and biofilm formation].
Ciok-Pater, Emilia; Białucha, Agata; Gospodarek, Eugenia; Ostafin, Agnieszka
2011-01-01
In recent years the increase in frequency of fungal infections with Candida sp. was noticed. These infections are connected with ability of Candida sp. to form biofilm on surfaces of biomaterials used in medicine. Furthermore fungal infections make serious therapeutic problems because ofbiofilm resistance to antifungal agents actually. The aim of the study was to evaluate the susceptibility to antifungal agents of Candida sp. and their ability to form biofilm on different biomaterials. 50 strains of Candida sp. isolated from patients of University Hospital No. 1 of dr A. Jurasz in Bydgoszcz were examined. API Candida (bioMérieux) tests were used to identify Candida sp. strains. The susceptibility of the yeast strains to antifungal agents was evaluated by ATB FUNGUS 2 INT (bioMérieux) tests. The susceptibility of examined strains to voriconazole, posaconazole, caspofungin and anidulafungin was assessed by means ofEtests (AB BIODISK) method employing drug concentrations from 0,002 to 32 microg/ml. All analysed strains were susceptible to amphotericin B and caspofungin. Biofilm formation on different biomaterials (silicon, latex, polychloride vinyl, polypropylene, nylon) was measured after 72 hour incubation at 37 degrees C. All examined yeasts formed biofilm on all analysed biomaterials. The highest number of strains formed biofilm on surface of polychloride vinyl: 23 (92,0%) by C. albicans strains and 24 (96,0%) Candida non-albicans strains. The lowest number of the strains formed biofilm on the surface of nylon: 12 (48,0%) of C. albicans strains and 9 (36,0%) of Candida non-albicans strains. The studied strains resistant to azoles and anidulafungin display stronger ability to form biofilm on surfaces of all analysed biomaterials.
1984-07-01
practices to ensure the health and well-being of self and co- workers . NAF 15 22. [MANAGERIAL ABILITY] The employee demonstrates the ability to plan...ABILITY] 21. The employee uses safe work practices to ensure the health and "- well-being of self and co- workers . [SAFETY MINDEDNESS] 22. The employee ...5 Outstanding COL COL APPRAISAL ITEMS 2 19. The employee uses safe work practices to ensure the health and well-being of self and co- workers . [SAFETY
Comparison of WAIS-III Short Forms for Measuring Index and Full-Scale Scores
ERIC Educational Resources Information Center
Girard, Todd A.; Axelrod, Bradley N.; Wilkins, Leanne K.
2010-01-01
This investigation assessed the ability of the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) short forms to estimate both index and IQ scores in a large, mixed clinical sample (N = 809). More specifically, a commonly used modification of Ward's seven-subtest short form (SF7-A), a recently proposed index-based SF7-C and eight-subtest…
Refractory Ceramic Foams for Novel Applications
NASA Technical Reports Server (NTRS)
Stackpoole, M.
2008-01-01
Workers at NASA Ames Research center are endeavoring to develop durable, oxidation-resistant, foam thermal protection systems (TPSs) that would be suitable for covering large exterior spacecraft surfaces, would have low to moderate densities, and would have temperature capabilities comparable to those of carbon-based TPSs [reusable at 3,000 F (.1,650 C)] with application of suitable coatings. These foams may also be useful for repairing TPSs while in orbit. Moreover, on Earth as well as in outer space, these foams might be useful as catalyst supports and filters. Preceramic polymers are obvious candidates for use in making the foams in question. The use of these polymers offers advantages over processing routes followed in making conventional ceramics. Among the advantages are the ability to plastically form parts, the ability to form pyrolized ceramic materials at lower temperatures, and the ability to form high-purity microstructures having properties that can be tailored to satisfy requirements. Heretofore, preceramic polymers have been used mostly in the production of such low-dimensional products as fibers because the loss of volatiles during pyrolysis of the polymers leads to porosity and large shrinkage (in excess of 30 percent). In addition, efforts to form bulk structures from preceramic polymers have resulted in severe cracking during pyrolysis. However, because the foams in question would consist of networks of thin struts (in contradistinction to nonporous dense solids), these foams are ideal candidates for processing along a preceramic-polymer route.
DECREASED LEVEL OF CORD BLOOD CIRCULATING ENDOTHELIAL COLONY-FORMING CELLS IN PREECLAMPSIA
Muñoz-Hernandez, Rocio; Miranda, Maria L.; Stiefel, Pablo; Lin, Ruei-Zeng; Praena-Fernández, Juan M.; Dominguez-Simeon, Maria J.; Villar, Jose; Moreno-Luna, Rafael; Melero-Martin, Juan M.
2014-01-01
Preeclampsia is a pregnancy-related disorder associated with increased cardiovascular risk for the offspring. Endothelial colony-forming cells (ECFCs) are a subset of circulating endothelial progenitor cells that participate in the formation of vasculature during development. However, the effect of preeclampsia on fetal levels of ECFCs is largely unknown. In this study, we sought to determine whether cord blood ECFC abundance and function are altered in preeclampsia. We conducted a prospective cohort study that included women with normal (n=35) and preeclamptic (n=15) pregnancies. We measured ECFC levels in the umbilical cord blood of neonates and characterized ECFC phenotype, cloning-forming ability, proliferation and migration towards VEGF-A and FGF-2, in vitro formation of capillary-like structures, and in vivo vasculogenic ability in immunodeficient mice. We found that the level of cord blood ECFCs was statistically lower in preeclampsia than in control pregnancies (P = .04), a reduction that was independent of other obstetric factors. In addition, cord blood ECFCs from preeclamptic pregnancies required more time to emerge in culture than control ECFCs. However, once derived in culture, ECFC function was deemed normal and highly similar between preeclampsia and control, including the ability to form vascular networks in vivo. This study demonstrates that preeclampsia affects ECFC abundance in neonates. A reduced level of ECFCs during preeclamptic pregnancies may contribute to an increased risk of developing future cardiovascular events. PMID:24752434
Freeman, Spencer A; McLeod, Sarah J; Dukowski, Janet; Austin, Pamela; Lee, Crystal C Y; Millen-Martin, Brandie; Kubes, Paul; McCafferty, Donna-Marie; Gold, Michael R; Roskelley, Calvin D
2010-06-01
The Rap1 GTPase is a master regulator of cell adhesion, polarity, and migration. We show that both blocking Rap1 activation and expressing a constitutively active form of Rap1 reduced the ability of B16F1 melanoma cells to extravasate from the microvasculature and form metastatic lesions in the lungs. This correlated with a decreased ability of the tumor cells to undergo transendothelial migration (TEM) in vitro and form dynamic, F-actin-rich pseudopodia that penetrate capillary endothelial walls in vivo. Using multiple tumor cell lines, we show that the inability to form these membrane protrusions, which likely promote TEM and extravasation, can be explained by altered adhesion dynamics and impaired cell polarization that result when Rap1 activation or cycling is perturbed. Thus, targeting Rap1 could be a useful approach for reducing the metastatic dissemination of tumor cells that undergo active TEM. Copyright 2010 AACR.
Medial prefrontal cortex subserves diverse forms of self-reflection.
Jenkins, Adrianna C; Mitchell, Jason P
2011-01-01
The ability to think about oneself--to self--reflect--is one of the defining features of the human mind. Recent research has suggested that this ability may be subserved by a particular brain region: the medial prefrontal cortex (MPFC). However, although humans can contemplate a variety of different aspects of themselves, including their stable personality traits, current feelings, and physical attributes, no research has directly examined the extent to which these different forms of self-reflection are subserved by common mechanisms. To address this question, participants were scanned using functional magnetic resonance imaging (fMRI) while making judgments about their own personality traits, current mental states, and physical attributes as well as those of another person. Whereas some brain regions responded preferentially during only one form of self-reflection, a robust region of MPFC was engaged preferentially during self-reflection across all three types of judgment. These results suggest that--although dissociable--diverse forms of self-referential thought draw on a shared cognitive process subserved by MPFC.
The effect of different oxygen exchange layers on TaO x based RRAM devices
NASA Astrophysics Data System (ADS)
Alamgir, Zahiruddin; Holt, Joshua; Beckmann, Karsten; Cady, Nathaniel C.
2018-01-01
In this work, we investigated the effect of the oxygen exchange layer (OEL) on the resistive switching properties of TaO x based memory cells. It was found that the forming voltage, SET-RESET voltage, R off, R on and retention properties are strongly correlated with the oxygen scavenging ability of the OEL, and the resulting oxygen vacancy formation ability of this layer. Higher forming voltage was observed for OELs having lower electronegativity/lower Gibbs free energy for oxide formation, and devices fabricated with these OELs exhibited an increased memory window, when using similar SET-RESET voltage range.
Discontinuities of Plastic Deformation in Metallic Glasses with Different Glass Forming Ability
NASA Astrophysics Data System (ADS)
Hurakova, Maria; Csach, Kornel; Miskuf, Jozef; Jurikova, Alena; Demcak, Stefan; Ocelik, Vaclav; Hosson, Jeff Th. M. De
The metallic ribbons Fe40Ni40B20, Cu47Ti35Zr11Ni6Si1 and Zr65Cu17.5Ni10Al7.5 with different microhardness and glass forming ability were studied at different loading rates from 0.05 to 100 mN/s. We describe in details the differences in elemental discontinuities on the loading curves for the studied alloys. It was found that the discontinuities began at a certain local deformation independently on the macroscopic mechanical properties of a ribbon. More developed discontinuities at higher deformations are created for the materials with lower microhardness and so lower strength.
Polymerization initated at sidewalls of carbon nanotubes
NASA Technical Reports Server (NTRS)
Tour, James M. (Inventor); Hudson, Jared L. (Inventor); Krishnamoorti, Ramanan (Inventor); Yurekli, Koray (Inventor); Mitchell, Cynthia A. (Inventor)
2011-01-01
The present invention is directed to aryl halide (such as aryl bromide) functionalized carbon nanotubes that can be utilized in anionic polymerization processes to form polymer-carbon nanotube materials with improved dispersion ability in polymer matrices. In this process the aryl halide is reacted with an alkyllithium species or is reacted with a metal to replace the aryl-bromine bond with an aryl-lithium or aryl-metal bond, respectively. It has further been discovered that other functionalized carbon nanotubes, after deprotonation with a deprotonation agent, can similarly be utilized in anionic polymerization processes to form polymer-carbon nanotube materials. Additionally or alternatively, a ring opening polymerization process can be performed. The resultant materials can be used by themselves due to their enhanced strength and reinforcement ability when compared to their unbound polymer analogs. Additionally, these materials can also be blended with pre-formed polymers to establish compatibility and enhanced dispersion of nanotubes in otherwise hard to disperse matrices resulting in significantly improved material properties. The resultant polymer-carbon nanotube materials can also be used in drug delivery processes due to their improved dispersion ability and biodegradability, and can also be used for scaffolding to promote cellular growth of tissue.
Holt, C; Wahlgren, N M; Drakenberg, T
1996-01-01
The ability of casein in the form of colloidal-sized casein micelles to modulate the phase separation of calcium phosphate during milk secretion is adapted to produce nanometre-sized particles of calcium phosphate stabilized by a casein phosphopeptide (nanoclusters). The nanoclusters were prepared from an undersaturated solution of salts and the peptide by raising the pH homogeneously from about 5.5 to 6.7 with urea plus urease. Chemical analysis and IR spectroscopy showed that they comprise an amorphous dicalcium phosophate bound to the phosphopeptide. Multinuclear NMR spectroscopy of the cluster solutions showed that the small ions and free peptide in the solution were in a state of dynamic exchange with the nanoclusters. The peptide is linked to the calcium phosphate through its sequence of phosphorylated residues, but, in a proportion of adsorbed conformational states, the termini retain the conformational freedom of the unbound peptide. The ability of casein to form nanoclusters in milk suggests a more general mechanism for avoiding pathological calcification and regulating calcium flow in tissues and biological fluids exposed to or containing high concentrations of calcium. PMID:8615755
ERIC Educational Resources Information Center
Gastgeb, Holly Zajac; Dundas, Eva M.; Minshew, Nancy J.; Strauss, Mark S.
2012-01-01
There is a growing amount of evidence suggesting that individuals with autism have difficulty with categorization. One basic cognitive ability that may underlie this difficulty is the ability to abstract a prototype. The current study examined prototype and category formation with dot patterns in high-functioning adults with autism and matched…
Interference Control, Working Memory Capacity, and Cognitive Abilities: A Latent Variable Analysis
ERIC Educational Resources Information Center
Unsworth, Nash
2010-01-01
The present study examined whether various indices of interference control were related to one another and to other cognitive abilities. It was found that the interference control measures were weakly correlated and could form a single factor that was related to overall memory performance on the tasks as well as to measures of working memory…
Rapid Fast-Mapping Abilities in 2-Year-Olds
ERIC Educational Resources Information Center
Spiegel, Chad; Halberda, Justin
2011-01-01
Learning a new word consists of two primary tasks that have often been conflated into a single process: "referent selection", in which a child must determine the correct referent of a novel label, and "referent retention", which is the ability to store this newly formed label-object mapping in memory for later use. In addition, children must be…
ERIC Educational Resources Information Center
Kuntay, Aylin C.; Ozyurek, Asli
2006-01-01
Pragmatic development requires the ability to use linguistic forms, along with non-verbal cues, to focus an interlocutor's attention on a referent during conversation. We investigate the development of this ability by examining how the use of demonstratives is learned in Turkish, where a three-way demonstrative system ("bu,"…
ERIC Educational Resources Information Center
Ulrich, Catherine; Wilkins, Jesse L. M.
2017-01-01
Background: Students' ability to construct and coordinate units has been found to have far-reaching implications for their ability to develop sophisticated understandings of key middle-grade mathematical topics such as fractions, ratios, proportions, and algebra, topics that form the base of understanding for most STEM-related fields. Most of the…
Some Effects of Social Class and Race on Children's Language and Intellectual Abilities.
ERIC Educational Resources Information Center
Whiteman, Martin; And Others
A cross-sectional study of 292 first and fifth grade Negro and white children examined the relationship between environmental factors and performance test scores of verbal and cognitive ability. The socioeconomic status (SES) of each subject was determined and included in a deprivation index formed by obtaining a composite score for each subject…
ERIC Educational Resources Information Center
Lin, Pei-Yi; Schunn, Christian D.
2016-01-01
Learners encounter science in a wide variety of contexts beyond the science classroom which collectively could be quite influential on student attitudes and abilities. But relatively little is known about the relative influence of different forms of informal science experiences, especially for the kinds of experiences that students typically…
ERIC Educational Resources Information Center
Deacon, S. Helene; Benere, Jenna; Castles, Anne
2012-01-01
There is increasing evidence of a relationship between orthographic processing skill, or the ability to form, store and access word representations, and reading ability. Empirical research to date has not, however, clarified the direction of this relationship. We examined this question in a three-year longitudinal study of children from Grades 1…
ERIC Educational Resources Information Center
Gamino, Jacquelyn F.; Chapman, Sandra B.; Cook, Lori G.
2009-01-01
Little is known about strategic learning ability in preteens and adolescents with traumatic brain injury (TBI). Strategic learning is the ability to combine and synthesize details to form abstracted gist-based meanings, a higher-order cognitive skill associated with frontal lobe functions and higher classroom performance. Summarization tasks were…
Basic-level and superordinate-like categorical representations in early infancy.
Behl-Chadha, G
1996-08-01
A series of experiments using the paired-preference procedure examined 3- to 4-month-old infants' ability to form perceptually based categorical representations in the domains of natural kinds and artifacts and probed the underlying organizational structure of these representations. Experiments 1 and 2 found that infants could form categorical representations for chairs that excluded exemplars of couches, beds, and tables and also for couches that excluded exemplars of chairs, beds, and tables. Thus, the adult-like exclusivity shown by infants in the categorization of various animal pictures at the basic-level extends to the domain of artifacts as well--an ecologically significant ability given the numerous artifacts that populate the human environment. Experiments 3 and 4 examined infants' ability to form superordinate-like or global categorical representations for mammals and furniture. It was found that infants could form a global representation for mammals that included novel mammals and excluded other non-mammalian animals such as birds and fish as well as items from cross-ontological categories such as furniture. In addition, it was found that infants formed a representation for furniture that included novel categories of furniture and excluded exemplars from the cross-ontological category of mammals; however, it was less clear if infants' global representation for furniture also excluded other artifacts such as vehicles and thus the category of furniture may have been less exclusively represented. Overall, the present findings, by showing the availability of perceptually driven basic and superordinate-like representations in early infancy that closely correspond to adult conceptual categories, underscore the importance of these early representations for later conceptual representations.
Gordon, Katherine R.; McGregor, Karla K.; Waldier, Brigitte; Curran, Maura K.; Gomez, Rebecca L.; Samuelson, Larissa K.
2016-01-01
Research on word learning has focused on children’s ability to identify a target object when given the word form after a minimal number of exposures to novel word-object pairings. However, relatively little research has focused on children’s ability to retrieve the word form when given the target object. The exceptions involve asking children to recall and produce forms, and children typically perform near floor on these measures. In the current study, 3- to 5-year-old children were administered a novel test of word form that allowed for recognition memory and manual responses. Specifically, when asked to label a previously trained object, children were given three forms to choose from: the target, a minimally different form, and a maximally different form. Children demonstrated memory for word forms at three post-training delays: 10 mins (short-term), 2–3 days (long-term), and 6 months to 1 year (very long-term). However, children performed worse at the very long-term delay than the other time points, and the length of the very long-term delay was negatively related to performance. When in error, children were no more likely to select the minimally different form than the maximally different form at all time points. Overall, these results suggest that children remember word forms that are linked to objects over extended post-training intervals, but that their memory for the forms gradually decreases over time without further exposures. Furthermore, memory traces for word forms do not become less phonologically specific over time; rather children either identify the correct form, or they perform at chance. PMID:27729880
Measurement properties of the Spinal Cord Injury-Functional Index (SCI-FI) short forms.
Heinemann, Allen W; Dijkers, Marcel P; Ni, Pengsheng; Tulsky, David S; Jette, Alan
2014-07-01
To evaluate the psychometric properties of the Spinal Cord Injury-Functional Index (SCI-FI) short forms (basic mobility, self-care, fine motor, ambulation, manual wheelchair, and power wheelchair) based on internal consistency; correlations between short forms banks, full item bank forms, and a 10-item computer adaptive test version; magnitude of ceiling and floor effects; and test information functions. Cross-sectional cohort study. Six rehabilitation hospitals in the United States. Individuals with traumatic spinal cord injury (N=855) recruited from 6 national Spinal Cord Injury Model Systems facilities. Not applicable. SCI-FI full item bank, 10-item computer adaptive test, and parallel short form scores. The SCI-FI short forms (with separate versions for individuals with paraplegia and tetraplegia) demonstrate very good internal consistency, group-level reliability, excellent correlations between short forms and scores based on the total item bank, and minimal ceiling and floor effects (except ceiling effects for persons with paraplegia on self-care, fine motor, and power wheelchair ability and floor effects for persons with tetraplegia on self-care, fine motor, and manual wheelchair ability). The test information functions are acceptable across the range of scores where most persons in the sample performed. Clinicians and researchers should consider the SCI-FI short forms when computer adaptive testing is not feasible. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Smolík, Filip; Kríž, Adam
2015-01-01
Imageability is the ability of words to elicit mental sensory images of their referents. Recent research has suggested that imageability facilitates the processing and acquisition of inflected word forms. The present study examined whether inflected word forms are acquired earlier in highly imageable words in Czech children. Parents of 317…
Bello, Katrina D; Goharpey, Nahal; Crewther, Sheila G; Crewther, David P
2008-01-01
Background Assessment of 'potential intellectual ability' of children with severe intellectual disability (ID) is limited, as current tests designed for normal children do not maintain their interest. Thus a manual puzzle version of the Raven's Coloured Progressive Matrices (RCPM) was devised to appeal to the attentional and sensory preferences and language limitations of children with ID. It was hypothesized that performance on the book and manual puzzle forms would not differ for typically developing children but that children with ID would perform better on the puzzle form. Methods The first study assessed the validity of this puzzle form of the RCPM for 76 typically developing children in a test-retest crossover design, with a 3 week interval between tests. A second study tested performance and completion rate for the puzzle form compared to the book form in a sample of 164 children with ID. Results In the first study, no significant difference was found between performance on the puzzle and book forms in typically developing children, irrespective of the order of completion. The second study demonstrated a significantly higher performance and completion rate for the puzzle form compared to the book form in the ID population. Conclusion Similar performance on book and puzzle forms of the RCPM by typically developing children suggests that both forms measure the same construct. These findings suggest that the puzzle form does not require greater cognitive ability but demands sensory-motor attention and limits distraction in children with severe ID. Thus, we suggest the puzzle form of the RCPM is a more reliable measure of the non-verbal mentation of children with severe ID than the book form. PMID:18671882
Bello, Katrina D; Goharpey, Nahal; Crewther, Sheila G; Crewther, David P
2008-08-01
Assessment of 'potential intellectual ability' of children with severe intellectual disability (ID) is limited, as current tests designed for normal children do not maintain their interest. Thus a manual puzzle version of the Raven's Coloured Progressive Matrices (RCPM) was devised to appeal to the attentional and sensory preferences and language limitations of children with ID. It was hypothesized that performance on the book and manual puzzle forms would not differ for typically developing children but that children with ID would perform better on the puzzle form. The first study assessed the validity of this puzzle form of the RCPM for 76 typically developing children in a test-retest crossover design, with a 3 week interval between tests. A second study tested performance and completion rate for the puzzle form compared to the book form in a sample of 164 children with ID. In the first study, no significant difference was found between performance on the puzzle and book forms in typically developing children, irrespective of the order of completion. The second study demonstrated a significantly higher performance and completion rate for the puzzle form compared to the book form in the ID population. Similar performance on book and puzzle forms of the RCPM by typically developing children suggests that both forms measure the same construct. These findings suggest that the puzzle form does not require greater cognitive ability but demands sensory-motor attention and limits distraction in children with severe ID. Thus, we suggest the puzzle form of the RCPM is a more reliable measure of the non-verbal mentation of children with severe ID than the book form.
Compulsory "Foreign Language Activities" in Japanese Primary Schools
ERIC Educational Resources Information Center
Hashimoto, Kayoko
2011-01-01
From 2011, the new curriculum for introducing English to Japanese primary schools will be fully implemented in the form of "foreign language activities". This innovation forms part of the government's plan to cultivate "Japanese with English abilities", a development based on the awareness, particularly in the business sector,…
48 CFR 315.204-5 - Part IV-Representations and instructions.
Code of Federal Regulations, 2013 CFR
2013-10-01
... as using too few.) (3) Examples of topics that form a basis for evaluation factors. Typical examples of topics that form a basis for the development of evaluation factors are listed in the following... special research, test, and other equipment or facilities. (vii) Managerial capability (ability to achieve...
48 CFR 315.204-5 - Part IV-Representations and instructions.
Code of Federal Regulations, 2014 CFR
2014-10-01
... as using too few.) (3) Examples of topics that form a basis for evaluation factors. Typical examples of topics that form a basis for the development of evaluation factors are listed in the following... special research, test, and other equipment or facilities. (vii) Managerial capability (ability to achieve...
48 CFR 315.204-5 - Part IV-Representations and instructions.
Code of Federal Regulations, 2012 CFR
2012-10-01
... as using too few.) (3) Examples of topics that form a basis for evaluation factors. Typical examples of topics that form a basis for the development of evaluation factors are listed in the following... special research, test, and other equipment or facilities. (vii) Managerial capability (ability to achieve...
Comparative Economic Organization: The Analysis of Discrete Structural Alternatives.
ERIC Educational Resources Information Center
Williamson, Oliver E.
1991-01-01
Combines institutional economics with aspects of contract law and organization theory to identify and explicate the key differences distinguishing three generic forms of economic organization: market, hybrid, and hierarchy. These generic forms are distinguished by different coordinating and control mechanisms and by different abilities to adapt to…
New technologies for managing cotton modules
USDA-ARS?s Scientific Manuscript database
New cotton harvesters with the ability to form seed cotton modules have changed the way that cotton is stored and handled before ginning. Cylindrical or “round” modules formed by John Deere cotton pickers and strippers are wrapped in three layers of plastic material to protect the cotton and mainta...
Normal form from biological motion despite impaired ventral stream function.
Gilaie-Dotan, S; Bentin, S; Harel, M; Rees, G; Saygin, A P
2011-04-01
We explored the extent to which biological motion perception depends on ventral stream integration by studying LG, an unusual case of developmental visual agnosia. LG has significant ventral stream processing deficits but no discernable structural cortical abnormality. LG's intermediate visual areas and object-sensitive regions exhibit abnormal activation during visual object perception, in contrast to area V5/MT+ which responds normally to visual motion (Gilaie-Dotan, Perry, Bonneh, Malach, & Bentin, 2009). Here, in three studies we used point light displays, which require visual integration, in adaptive threshold experiments to examine LG's ability to detect form from biological and non-biological motion cues. LG's ability to detect and discriminate form from biological motion was similar to healthy controls. In contrast, he was significantly deficient in processing form from non-biological motion. Thus, LG can rely on biological motion cues to perceive human forms, but is considerably impaired in extracting form from non-biological motion. Finally, we found that while LG viewed biological motion, activity in a network of brain regions associated with processing biological motion was functionally correlated with his V5/MT+ activity, indicating that normal inputs from V5/MT+ might suffice to activate his action perception system. These results indicate that processing of biologically moving form can dissociate from other form processing in the ventral pathway. Furthermore, the present results indicate that integrative ventral stream processing is necessary for uncompromised processing of non-biological form from motion. Copyright © 2011 Elsevier Ltd. All rights reserved.
Thompson, J Mark; Tuch, Richard
Improving a patient's ability to form and maintain satisfactory interpersonal relations is an important goal in many therapies. A mentalization-based approach to treatment is ideally suited to achieve this end to the extent it's designed to help improve a patient's ability to form more nuanced guesses about why others act as they do, based on a more accurate "read" of that individual's beliefs and desires. Interpersonal difficulties often issue when patients remain insistent on their own interpretation of another's motives that fly in the face of that individual's understanding of what is "driving" them. Helping patients explore the basis upon which they'd formed their conclusions about others goes a ways toward opening their mind to the possibility that things are a bit more complicated than first imaged. This in turn leads to greater curiosity and willingness to explore their own narratives and perceptions.
Who Cares about Caring in Early Childhood Teacher Education Programs?
ERIC Educational Resources Information Center
McNamee, Abigail; Mercurio, Mia; Peloso, Jeanne M.
2007-01-01
The ability to care for oneself, near and distant others, animals, plants, human-made objects, and even ideas is an antidote for violence in its many forms as experienced in childhood as well as adulthood. This article makes a case for facilitating the development of the ability to care as children develop. The authors emphasize the importance of…
ERIC Educational Resources Information Center
Marote, Melissa A.
2011-01-01
This heuristic study involving seven coresearchers, which included the author, explores the experiences of women from mother-present/father-absent homes and their ability to form and maintain close female friendships. The heuristic research model was chosen to provide the opportunity to conduct research in a very personalized, collaborative way…
The Relation of Age and Reading Ability to Memory Processing.
ERIC Educational Resources Information Center
Marrach, Alexa; Fireman, Gary
This study examined the relation of reading ability, age, and familiarity to iconic and short-term memory processing and how the familiarity of the stimuli affects recall. A total of 10 children in grades 2 through 6 and 10 adults were shown novel abstract forms, words, and non-words varying in order of approximation to English, for 50 msec., 500…
USDA-ARS?s Scientific Manuscript database
Salmonella enterica serovar Heidelberg (American Type Culture Collection; ATCC 8326) was examined for the ability to adapt to the homologous stress of chlorine through exposure to increasing chlorine concentrations (25 ppm daily increments) in tryptic soy broth (TSB). The tested strain exhibited an ...
Synthetic Synchronisation: From Attention and Multi-Tasking to Negative Capability and Judgment
ERIC Educational Resources Information Center
Stables, Andrew
2013-01-01
Educational literature has tended to focus, explicitly and implicitly, on two kinds of task orientation: the ability either to focus on a single task, or to multi-task. A third form of orientation characterises many highly successful people. This is the ability to combine several tasks into one: to "kill two (or more) birds with one…
Distance Decay of Similarity in Neotropical Diatom Communities
Wetzel, Carlos E.; Bicudo, Denise de C.; Ector, Luc; Lobo, Eduardo A.; Soininen, Janne; Landeiro, Victor L.; Bini, Luis M.
2012-01-01
Background The regression of similarity against distance unites several ecological phenomena, and thus provides a highly useful approach for illustrating the spatial turnover across sites. Our aim was to test whether the rates of decay in community similarity differ between diatom growth forms suggested to show different dispersal ability. We hypothesized that the diatom group with lower dispersal ability (i.e. periphyton) would show higher distance decay rates than a group with higher dispersal ability (i.e. plankton). Methods/Principal findings Periphyton and phytoplankton samples were gathered at sites distributed over an area of approximately 800 km length in the Negro River, Amazon basin, Brazil, South America (3°08′00″S; 59°54′30″W). Distance decay relationships were then estimated using distance-based regressions, and the coefficients of these regressions were compared among the groups with different dispersal abilities to assess our predictions. We found evidence that different tributaries and reaches of the Negro River harbor different diatom communities. As expected, the rates of distance decay in community similarity were higher for periphyton than for phytoplankton indicating the lower dispersal ability of periphytic taxa. Conclusions/Significance Our study demonstrates that the comparison of distance decay relationships among taxa with similar ecological requirements, but with different growth form and thus dispersal ability provides a sound approach to evaluate the effects of dispersal ability on beta diversity patterns. Our results are also in line with the growing body of evidence indicating that microorganisms exhibit biogeographic patterns. Finally, we underscore that clumbing all microbial taxa into one group may be a flawed approach to test whether microbes exhibit biogeographic patterns. PMID:23028767
Ray, Siddharth; Miller, Meghan; Karalunas, Sarah; Robertson, C.J.; Grayson, David; Cary, Paul; Hawkey, Elizabeth; Painter, Julia G.; Kriz, Daniel; Fombonne, Eric; Nigg, Joel T.; Fair, Damien A.
2015-01-01
Attention deficit hyperactive disorder (ADHD) and Autism spectrum disorders (ASD) are two of the most common and vexing neurodevelopmental disorders among children. Although the two disorders share many behavioral and neuropsychological characteristics, most MRI studies examine only one of the disorders at a time. Using graph theory combined with structural and functional connectivity, we examined the large-scale network organization among three groups of children: a group with ADHD (8-12 years, n = 20), a group with ASD (7-13 years, n = 16), and typically developing controls (TD) (8-12 years, n = 20). We apply the concept of the rich-club organization, whereby central, highly connected hub regions are also highly connected to themselves. We examine the brain into two different network domains: (1) inside a rich-club network phenomena, and (2) outside a rich-club network phenomena. ASD and ADHD populations had markedly different patterns of rich club and non rich-club connections in both functional and structural data. The ASD group exhibited higher connectivity in structural and functional networks but only inside the rich-club networks. These findings were replicated using the autism brain imaging data exchange (ABIDE) dataset with ASD (n = 85) and TD (n = 101). The ADHD group exhibited a lower generalized fractional anisotropy (GFA) and functional connectivity inside the rich-club networks, but a higher number of axonal fibers and correlation coefficient values outside the rich-club. Despite some shared biological features and frequent comorbity, these data suggest ADHD and ASD exhibit distinct large-scale connectivity patterns in middle childhood. PMID:25116862
Li, Yu; Zhang, Linjun; Xia, Zhichao; Yang, Jie; Shu, Hua; Li, Ping
2017-01-01
Reading plays a key role in education and communication in modern society. Learning to read establishes the connections between the visual word form area (VWFA) and language areas responsible for speech processing. Using resting-state functional connectivity (RSFC) and Granger Causality Analysis (GCA) methods, the current developmental study aimed to identify the difference in the relationship between the connections of VWFA-language areas and reading performance in both adults and children. The results showed that: (1) the spontaneous connectivity between VWFA and the spoken language areas, i.e., the left inferior frontal gyrus/supramarginal gyrus (LIFG/LSMG), was stronger in adults compared with children; (2) the spontaneous functional patterns of connectivity between VWFA and language network were negatively correlated with reading ability in adults but not in children; (3) the causal influence from LIFG to VWFA was negatively correlated with reading ability only in adults but not in children; (4) the RSFCs between left posterior middle frontal gyrus (LpMFG) and VWFA/LIFG were positively correlated with reading ability in both adults and children; and (5) the causal influence from LIFG to LSMG was positively correlated with reading ability in both groups. These findings provide insights into the relationship between VWFA and the language network for reading, and the role of the unique features of Chinese in the neural circuits of reading. PMID:28690507
Li, Yu; Zhang, Linjun; Xia, Zhichao; Yang, Jie; Shu, Hua; Li, Ping
2017-01-01
Reading plays a key role in education and communication in modern society. Learning to read establishes the connections between the visual word form area (VWFA) and language areas responsible for speech processing. Using resting-state functional connectivity (RSFC) and Granger Causality Analysis (GCA) methods, the current developmental study aimed to identify the difference in the relationship between the connections of VWFA-language areas and reading performance in both adults and children. The results showed that: (1) the spontaneous connectivity between VWFA and the spoken language areas, i.e., the left inferior frontal gyrus/supramarginal gyrus (LIFG/LSMG), was stronger in adults compared with children; (2) the spontaneous functional patterns of connectivity between VWFA and language network were negatively correlated with reading ability in adults but not in children; (3) the causal influence from LIFG to VWFA was negatively correlated with reading ability only in adults but not in children; (4) the RSFCs between left posterior middle frontal gyrus (LpMFG) and VWFA/LIFG were positively correlated with reading ability in both adults and children; and (5) the causal influence from LIFG to LSMG was positively correlated with reading ability in both groups. These findings provide insights into the relationship between VWFA and the language network for reading, and the role of the unique features of Chinese in the neural circuits of reading.
Project Integration Architecture: A Practical Demonstration of Information Propagation
NASA Technical Reports Server (NTRS)
Jones, William Henry
2005-01-01
One of the goals of the Project Integration Architecture (PIA) effort is to provide the ability to propagate information between disparate applications. With this ability, applications may then be formed into an application graph constituting a super-application. Such a super-application would then provide all of the analysis appropriate to a given technical system. This paper reports on a small demonstration of this concept in which a Computer Aided Design (CAD) application was connected to an inlet analysis code and geometry information automatically propagated from one to the other. The majority of the work reported involved not the technology of information propagation, but rather the conversion of propagated information into a form usable by the receiving application.
Collaboration in young children.
Tomasello, Michael; Hamann, Katharina
2012-01-01
Humans accomplish much of what they do in collaboration with others. In ontogeny, children's earliest abilities to collaborate develop in two basic steps. First, 1- and 2-year-olds learn to form with others joint goals and joint attention--which include an understanding of the individual roles and perspectives involved. Second, as they approach their third birthdays, children's collaborative interactions with others take on a more normative dimension involving obligations to the partner. In addition, their cognitive abilities to conceptualize simultaneously both their own role and perspective along with those of the other develop considerably as well. This form of collaborative interaction is underlain by species-unique skills and motivations for shared intentionality that make possible, ultimately, such things as complex cultural institutions.
[Synthesis and monolayer behaviors of 4-methyl-5-hydroxy-ethyl isothiazole stearic ester].
Shen, Yu-hua; Kong, Lin; Yang, Jia-xiang; Xie, An-jian; Qian, Jia-sheng; Ouyang, Jian-ming; Xia, Bing
2002-12-01
4-methyl-5-hydroxy-ethyl isothiazole stearic ester (HISE) was synthesized and characterized by FTIR spectroscopy, 1H NMR and MS. The monolayer-forming ability of HISE was studied in subphases with different pH values using isotherms of surface pressure-area per molecule (pi-A). It was observed that the collapse pressure and the film-forming ability of the monolayers of HISE increased gradually as pH values ascended. Research of differentiated pi-A curves (d pi(/dA-A) indicated that there were one or two phase change points during the compressing process, and the incompressibility and the stability of HISE monolayers on alkalescent subphases were better than on acid subphases.
Lipopeptide surfactants: Production, recovery and pore forming capacity.
Inès, Mnif; Dhouha, Ghribi
2015-09-01
Lipopeptides are microbial surface active compounds produced by a wide variety of bacteria, fungi and yeast. They are characterized by highly structural diversity and have the ability to decrease the surface and interfacial tension at the surface and interface, respectively. Surfactin, iturin and fengycin of Bacillus subtilis are among the most studied lipopeptides. This review will present the main factors encountering lipopeptides production along with the techniques developed for their extraction and purification. Moreover, we will discuss their ability to form pores and destabilize biological membrane permitting their use as antimicrobial, hemolytic and antitumor agents. These open great potential applications in biomediacal, pharmaceutic and agriculture fields. Copyright © 2015 Elsevier Inc. All rights reserved.
Pathogenicity of exopolysaccharide-producing Actinomyces oris isolated from an apical abscess lesion
Yamane, K; Nambu, T; Yamanaka, T; Ishihara, K; Tatami, T; Mashimo, C; Walker, C B; Leung, K-P; Fukushima, H
2013-01-01
Aim To demonstrate a capacity for producing exopolysaccharides (EPSs) and an ability to form biofilm on abiotic materials of Actinomyces oris strain K20. Methodology The productivity of EPSs and the ability to form biofilm of strain K20 were evaluated by measuring viscosity of spent culture media and by scanning electron microscopy (SEM) and the biofilm assay on microtitre plates, respectively. High-performance liquid chromatography was used to determine the chemical composition of the viscous materials. To examine the role of the viscous materials attributable to the pathogenicity in this organism, the ability of strain K20 to induce abscess formation was compared in mice to that of ATCC 27044. Results The viscosity of the spent culture media of K20 was significantly higher than that of ATCC 27044. Strain K20 showed dense meshwork structures around the cells and formed biofilms on microtitre plates, whereas ATCC 27044 did not. Chemical analysis of the viscous materials revealed that they were mainly composed of neutral sugars with mannose constituting 77.5% of the polysaccharides. Strain K20 induced persistent abscesses in mice lasting at least 5 days at a concentration of 108 cells mL−1, whereas abscesses induced by ATCC 27044 healed and disappeared or decreased in size at day 5. Conclusions Strain K20 produced EPSs, mainly consisting of mannose, and formed biofilms. This phenotype might play an important role for A. oris to express virulence through the progression of apical periodontitis. PMID:22900599
Yamane, K; Nambu, T; Yamanaka, T; Ishihara, K; Tatami, T; Mashimo, C; Walker, C B; Leung, K-P; Fukushima, H
2013-02-01
To demonstrate a capacity for producing exopolysaccharides (EPSs) and an ability to form biofilm on abiotic materials of Actinomyces oris strain K20. The productivity of EPSs and the ability to form biofilm of strain K20 were evaluated by measuring viscosity of spent culture media and by scanning electron microscopy (SEM) and the biofilm assay on microtitre plates, respectively. High-performance liquid chromatography was used to determine the chemical composition of the viscous materials. To examine the role of the viscous materials attributable to the pathogenicity in this organism, the ability of strain K20 to induce abscess formation was compared in mice to that of ATCC 27044. The viscosity of the spent culture media of K20 was significantly higher than that of ATCC 27044. Strain K20 showed dense meshwork structures around the cells and formed biofilms on microtitre plates, whereas ATCC 27044 did not. Chemical analysis of the viscous materials revealed that they were mainly composed of neutral sugars with mannose constituting 77.5% of the polysaccharides. Strain K20 induced persistent abscesses in mice lasting at least 5 days at a concentration of 10(8) cells mL(-1), whereas abscesses induced by ATCC 27044 healed and disappeared or decreased in size at day 5. Strain K20 produced EPSs, mainly consisting of mannose, and formed biofilms. This phenotype might play an important role for A. oris to express virulence through the progression of apical periodontitis. © 2012 International Endodontic Journal.
Decreased level of cord blood circulating endothelial colony-forming cells in preeclampsia.
Muñoz-Hernandez, Rocio; Miranda, Maria L; Stiefel, Pablo; Lin, Ruei-Zeng; Praena-Fernández, Juan M; Dominguez-Simeon, Maria J; Villar, Jose; Moreno-Luna, Rafael; Melero-Martin, Juan M
2014-07-01
Preeclampsia is a pregnancy-related disorder associated with increased cardiovascular risk for the offspring. Endothelial colony-forming cells (ECFCs) are a subset of circulating endothelial progenitor cells that participate in the formation of vasculature during development. However, the effect of preeclampsia on fetal levels of ECFCs is largely unknown. In this study, we sought to determine whether cord blood ECFC abundance and function are altered in preeclampsia. We conducted a prospective cohort study that included women with normal (n=35) and preeclamptic (n=15) pregnancies. We measured ECFC levels in the umbilical cord blood of neonates and characterized ECFC phenotype, cloning-forming ability, proliferation, and migration toward vascular endothelial growth factor-A and fibroblast growth factor-2, in vitro formation of capillary-like structures, and in vivo vasculogenic ability in immunodeficient mice. We found that the level of cord blood ECFCs was statistically lower in preeclampsia than in control pregnancies (P=0.04), a reduction that was independent of other obstetric factors. In addition, cord blood ECFCs from preeclamptic pregnancies required more time to emerge in culture than control ECFCs. However, once derived in culture, ECFC function was deemed normal and highly similar between preeclampsia and control, including the ability to form vascular networks in vivo. This study demonstrates that preeclampsia affects ECFC abundance in neonates. A reduced level of ECFCs during preeclamptic pregnancies may contribute to an increased risk of developing future cardiovascular events. © 2014 American Heart Association, Inc.
Giaschi, D; Regan, D
1997-09-01
Three-month-old infants can discriminate motion-defined (MD) form, but we do not know the age at which this ability reaches adult levels. Previous psychophysical evidence suggests that different neural mechanisms are involved in the processing of luminance-defined (LD) and MD spatial form in adults. This difference may be reflected in the development of LD versus MD form identification in children. We measured speed threshold for identifying MD letters, letter-chart (i.e, Snellen) acuity for high-contrast LD letters and single-letter acuity for high- and low-contrast LD letters. Forty-seven children between 3 and 12 years of age and 20 adult subjects were tested. Development to the adult level was observed as follows: low-contrast single-letter acuity before 3 years; high-contrast single-letter acuity by 5 to 6 years; the ability to identify MD letters by 7 to 8 years; letter-chart acuity by 9 to 10 years. MD form identification continues to mature in preschool children. LD form identification also matures in this age group but with a different time course. MD letters are not equivalent to low-contrast letters developmentally. Our findings provide further support for the hypothesis that the spatial aspects of MD and LD form are processed separately to some extent.
The relationship of global form and motion detection to reading fluency.
Englund, Julia A; Palomares, Melanie
2012-08-15
Visual motion processing in typical and atypical readers has suggested aspects of reading and motion processing share a common cortical network rooted in dorsal visual areas. Few studies have examined the relationship between reading performance and visual form processing, which is mediated by ventral cortical areas. We investigated whether reading fluency correlates with coherent motion detection thresholds in typically developing children using random dot kinematograms. As a comparison, we also evaluated the correlation between reading fluency and static form detection thresholds. Results show that both dorsal and ventral visual functions correlated with components of reading fluency, but that they have different developmental characteristics. Motion coherence thresholds correlated with reading rate and accuracy, which both improved with chronological age. Interestingly, when controlling for non-verbal abilities and age, reading accuracy significantly correlated with thresholds for coherent form detection but not coherent motion detection in typically developing children. Dorsal visual functions that mediate motion coherence seem to be related maturation of broad cognitive functions including non-verbal abilities and reading fluency. However, ventral visual functions that mediate form coherence seem to be specifically related to accurate reading in typically developing children. Copyright © 2012 Elsevier Ltd. All rights reserved.
Szczuka, Ewa; Urbańska, Katarzyna; Pietryka, Marta; Kaznowski, Adam
2013-01-01
Many serious diseases caused by Staphylococcus aureus appear to be associated with biofilms. Therefore, we investigated the biofilm-forming ability of the methicillin-resistant S. aureus (MRSA) isolates collected from hospitalized patients. As many as 96 % strains had the ability to form biofilm in vitro. The majority of S. aureus strains formed biofilm in ica-dependent mechanism. However, 23 % of MRSA isolates formed biofilm in ica-independent mechanism. Half of these strains carried fnbB genes encoding surface proteins fibronectin-binding protein B involved in intercellular accumulation and biofilm development in S. aureus strains. The biofilm structures were examined via confocal laser scanning microscopy (CLSM) and three-dimensional structures were reconstructed. The images obtained in CLSM revealed that the biofilm created by ica-positive strains was different from biofilm formed by ica-negative strains. The MRSA population showed a large genetic diversity and we did not find a single clone that occurred preferentially in hospital environment. Our results demonstrated the variation in genes encoding adhesins for the host matrix proteins (elastin, laminin, collagen, fibronectin, and fibrinogen) and in the gene involved in biofilm formation (icaA) within the majority of S. aureus clones.
Isolation of sphere-forming stem cells from the mouse inner ear.
Oshima, Kazuo; Senn, Pascal; Heller, Stefan
2009-01-01
The mammalian inner ear has very limited ability to regenerate lost sensory hair cells. This deficiency becomes apparent when hair cell loss leads to hearing loss as a result of either ototoxic insult or the aging process. Coincidently, with this inability to regenerate lost hair cells, the adult cochlea does not appear to harbor cells with a proliferative capacity that could serve as progenitor cells for lost cells. In contrast, adult mammalian vestibular sensory epithelia display a limited ability for hair cell regeneration, and sphere-forming cells with stem cell features can be isolated from the adult murine vestibular system. The neonatal inner ear, however, does harbor sphere-forming stem cells residing in cochlear and vestibular tissues. Here, we provide protocols to isolate sphere-forming stem cells from neonatal vestibular and cochlear sensory epithelia as well as from the spiral ganglion. We further describe procedures for sphere propagation, cell differentiation, and characterization of inner ear cell types derived from spheres. Sphere-forming stem cells from the mouse inner ear are an important tool for the development of cellular replacement strategies of damaged inner ears and are a bona fide progenitor cell source for transplantation studies.
Predicting functional ability in mild cognitive impairment with the Dementia Rating Scale-2.
Greenaway, Melanie C; Duncan, Noah L; Hanna, Sherrie; Smith, Glenn E
2012-06-01
We examined the utility of cognitive evaluation to predict instrumental activities of daily living (IADLs) and decisional ability in Mild Cognitive Impairment (MCI). Sixty-seven individuals with single-domain amnestic MCI were administered the Dementia Rating Scale-2 (DRS-2) as well as the Everyday Cognition assessment form to assess functional ability. The DRS-2 Total Scores and Initiation/Perseveration and Memory subscales were found to be predictive of IADLs, with Total Scores accounting for 19% of the variance in IADL performance on average. In addition, the DRS-2 Initiation/Perseveration and Total Scores were predictive of ability to understand information, and the DRS-2 Conceptualization helped predict ability to communicate with others, both key variables in decision-making ability. These findings suggest that performance on the DRS-2, and specific subscales related to executive function and memory, is significantly related to IADLs in individuals with MCI. These cognitive measures are also associated with decision-making-related abilities in MCI.
Students’ Cognitive Abilities in Plant Anatomy Practical Work
NASA Astrophysics Data System (ADS)
Setiono, S.; Rustaman, N. Y.; Rahmat, A.; Anggraeni, S.
2017-09-01
Cognitive abilities is fundamental for the students, as it is closely related to higher thinking skills such as the ability to think critically, creatively, and problem solving. This descriptive study aims to investigate the cognitive abilities of biology prospective teachers in the course of Plant Anatomy Practicum based on the cognitive process dimension and dimensions of knowledge the using the framework of Revision of Bloom taxonomy. A number of biology prospective teachers was involved in this study (n=42). The instrument used to collect data for students’ cognitive process mastery in the form of multiple choice with 5 options. Research finding shows that the average student’s cognitive ability is 68.10. The acquisition of knowledge mastery of cognitive ability is still under the criterion of mastery in the course of the Plant Anatomy Practicum (75). Validity and reliability of the instrument (0,71) and (0,81). It is necessary to design lecture programs both in the class and laboratory to develop student’ cognitive abilities.
The Bicomponent Pore-Forming Leucocidins of Staphylococcus aureus
Alonzo, Francis
2014-01-01
SUMMARY The ability to produce water-soluble proteins with the capacity to oligomerize and form pores within cellular lipid bilayers is a trait conserved among nearly all forms of life, including humans, single-celled eukaryotes, and numerous bacterial species. In bacteria, some of the most notable pore-forming molecules are protein toxins that interact with mammalian cell membranes to promote lysis, deliver effectors, and modulate cellular homeostasis. Of the bacterial species capable of producing pore-forming toxic molecules, the Gram-positive pathogen Staphylococcus aureus is one of the most notorious. S. aureus can produce seven different pore-forming protein toxins, all of which are believed to play a unique role in promoting the ability of the organism to cause disease in humans and other mammals. The most diverse of these pore-forming toxins, in terms of both functional activity and global representation within S. aureus clinical isolates, are the bicomponent leucocidins. From the first description of their activity on host immune cells over 100 years ago to the detailed investigations of their biochemical function today, the leucocidins remain at the forefront of S. aureus pathogenesis research initiatives. Study of their mode of action is of immediate interest in the realm of therapeutic agent design as well as for studies of bacterial pathogenesis. This review provides an updated perspective on our understanding of the S. aureus leucocidins and their function, specificity, and potential as therapeutic targets. PMID:24847020
Smith, James; Yang, Yiwen; Levy, Shahar; Adelusi, Oluwatoyin Oluwayemi; Hahn, Michael G; O'Neill, Malcolm A; Bar-Peled, Maor
2016-10-07
Apiose is a branched monosaccharide that is present in the cell wall pectic polysaccharides rhamnogalacturonan II and apiogalacturonan and in numerous plant secondary metabolites. These apiose-containing glycans are synthesized using UDP-apiose as the donor. UDP-apiose (UDP-Api) together with UDP-xylose is formed from UDP-glucuronic acid (UDP-GlcA) by UDP-Api synthase (UAS). It was hypothesized that the ability to form Api distinguishes vascular plants from the avascular plants and green algae. UAS from several dicotyledonous plants has been characterized; however, it is not known if avascular plants or green algae produce this enzyme. Here we report the identification and functional characterization of UAS homologs from avascular plants (mosses, liverwort, and hornwort), from streptophyte green algae, and from a monocot (duckweed). The recombinant UAS homologs all form UDP-Api from UDP-glucuronic acid albeit in different amounts. Apiose was detected in aqueous methanolic extracts of these plants. Apiose was detected in duckweed cell walls but not in the walls of the avascular plants and algae. Overexpressing duckweed UAS in the moss Physcomitrella patens led to an increase in the amounts of aqueous methanol-acetonitrile-soluble apiose but did not result in discernible amounts of cell wall-associated apiose. Thus, bryophytes and algae likely lack the glycosyltransferase machinery required to synthesize apiose-containing cell wall glycans. Nevertheless, these plants may have the ability to form apiosylated secondary metabolites. Our data are the first to provide evidence that the ability to form apiose existed prior to the appearance of rhamnogalacturonan II and apiogalacturonan and provide new insights into the evolution of apiose-containing glycans. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
Smith, James; Yang, Yiwen; Levy, Shahar; Adelusi, Oluwatoyin Oluwayemi; Hahn, Michael G.; O'Neill, Malcolm A.; Bar-Peled, Maor
2016-01-01
Apiose is a branched monosaccharide that is present in the cell wall pectic polysaccharides rhamnogalacturonan II and apiogalacturonan and in numerous plant secondary metabolites. These apiose-containing glycans are synthesized using UDP-apiose as the donor. UDP-apiose (UDP-Api) together with UDP-xylose is formed from UDP-glucuronic acid (UDP-GlcA) by UDP-Api synthase (UAS). It was hypothesized that the ability to form Api distinguishes vascular plants from the avascular plants and green algae. UAS from several dicotyledonous plants has been characterized; however, it is not known if avascular plants or green algae produce this enzyme. Here we report the identification and functional characterization of UAS homologs from avascular plants (mosses, liverwort, and hornwort), from streptophyte green algae, and from a monocot (duckweed). The recombinant UAS homologs all form UDP-Api from UDP-glucuronic acid albeit in different amounts. Apiose was detected in aqueous methanolic extracts of these plants. Apiose was detected in duckweed cell walls but not in the walls of the avascular plants and algae. Overexpressing duckweed UAS in the moss Physcomitrella patens led to an increase in the amounts of aqueous methanol-acetonitrile-soluble apiose but did not result in discernible amounts of cell wall-associated apiose. Thus, bryophytes and algae likely lack the glycosyltransferase machinery required to synthesize apiose-containing cell wall glycans. Nevertheless, these plants may have the ability to form apiosylated secondary metabolites. Our data are the first to provide evidence that the ability to form apiose existed prior to the appearance of rhamnogalacturonan II and apiogalacturonan and provide new insights into the evolution of apiose-containing glycans. PMID:27551039
Snel, G G M; Malvisi, M; Pilla, R; Piccinini, R
2014-12-05
It was hypothesized that biofilm could play an important role in the establishment of chronic Staphylococcus aureus bovine mastitis. The in vitro evaluation of biofilm formation can be performed either in closed/static or in flow-based systems. Efforts have been made to characterize the biofilm-forming ability of S. aureus mastitis isolates, however most authors used static systems and matrices other than UHT milk. It is not clear whether such results could be extrapolated to the mammary gland environment. Therefore, the present study aimed to investigate the biofilm-forming ability of S. aureus strains from subclinical bovine mastitis using the static method and a flow-based one. One hundred and twelve strains were tested by the classic tissue culture plate assay (TCP) and 30 out of them were also tested by a dynamic semi-quantitative assay using commercial UHT milk as culture medium (Milk Flow Culture, MFC) or Tryptic Soy Broth as control medium (TS Flow Culture, TSFC). Only 6 (20%) strains formed biofilm in milk under flow conditions, while 36.6% were considered biofilm-producers in TCP, and 93.3% produced biofilm in TSFC. No agreement was found between TCP, MFC and TSFC results. The association between strain genetic profile, determined by microarray, and biofilm-forming ability in milk was evaluated. Biofilm formation in MFC was significantly associated with the presence of those genes commonly found in bovine-associated strains, assigned to clonal complexes typically detected in mastitis. Based on our results, biofilm-forming potential of bovine strains should be critically analysed and tested applying conditions similar to mammary environment. Copyright © 2014 Elsevier B.V. All rights reserved.
Sleep duration predicts behavioral and neural differences in adult speech sound learning.
Earle, F Sayako; Landi, Nicole; Myers, Emily B
2017-01-01
Sleep is important for memory consolidation and contributes to the formation of new perceptual categories. This study examined sleep as a source of variability in typical learners' ability to form new speech sound categories. We trained monolingual English speakers to identify a set of non-native speech sounds at 8PM, and assessed their ability to identify and discriminate between these sounds immediately after training, and at 8AM on the following day. We tracked sleep duration overnight, and found that light sleep duration predicted gains in identification performance, while total sleep duration predicted gains in discrimination ability. Participants obtained an average of less than 6h of sleep, pointing to the degree of sleep deprivation as a potential factor. Behavioral measures were associated with ERP indexes of neural sensitivity to the learned contrast. These results demonstrate that the relative success in forming new perceptual categories depends on the duration of post-training sleep. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Sleep duration predicts behavioral and neural differences in adult speech sound learning
Earle, F. Sayako; Landi, Nicole; Myers, Emily B.
2016-01-01
Sleep is important for memory consolidation and contributes to the formation of new perceptual categories. This study examined sleep as a source of variability in typical learners’ ability to form new speech sound categories. We trained monolingual English speakers to identify a set of non-native speech sounds at 8PM, and assessed their ability to identify and discriminate between these sounds immediately after training, and at 8AM on the following day. We tracked sleep duration overnight, and found that light sleep duration predicted gains in identification performance, while total sleep duration predicted gains in discrimination ability. Participants obtained an average of less than 6 hours of sleep, pointing to the degree of sleep deprivation as a potential factor. Behavioral measures were associated with ERP indexes of neural sensitivity to the learned contrast. These results demonstrate that the relative success in forming new perceptual categories depends on the duration of post-training sleep. PMID:27793703
Cortés-Ruiz, Juan A; Pacheco-Aguilar, Ramón; Elena Lugo-Sánchez, M; Gisela Carvallo-Ruiz, M; García-Sánchez, Guillermina
2008-09-15
A protein concentrate from giant squid (Dosidicus gigas) was produced under acidic conditions and its functional-technological capability evaluated in terms of its gel-forming ability, water holding capacity and colour attributes. Technological functionality of the concentrate was compared with that of squid muscle and a neutral concentrate. Protein-protein aggregates insoluble at high ionic strength (I=0.5M), were detected in the acidic concentrate as result of processing with no preclusion of its gel-forming ability during the sol-to-gel thermal transition. Even though washing under acidic condition promoted autolysis of the myosin heavy chain, the acidic concentrate displayed an outstanding ability to gel giving samples with a gel strength of 455 and 1160gcm at 75% and 90% compression respectively, and an AA folding test grade indicative of high gel strength, elasticity, and cohesiveness. The process proved to be a good alternative for obtaining a functional protein concentrate from giant squid muscle. Copyright © 2008. Published by Elsevier Ltd.
Tucker-Drob, Elliot M
2013-06-01
Children whose parents have higher education enjoy greater age-linked gains in cognitive abilities and academic achievement. Different researchers have typically focused on different outcomes, and the extent to which parental education relates to multiple child outcomes via a single developmental pathway has received little empirical attention. This issue was examined by applying common factor structural equation models to a large (N = 4,810) nationally representative sample of kindergarten through 12 th grade children, who were measured on 6 distinct cognitive abilities and 5 distinct forms of knowledge and academic achievement. Results indicated that a single pathway accounted for the relations between parental education and age differences in children's cognitive abilities. However, additional unique pathways were necessary to account for the relations between parental education and age differences in academic knowledge and mathematics. These results suggest that while socioeconomic differences are largely manifest in global aspects of cognitive development, they have incremental relations with some forms of academic achievement.
Hydroperoxides as Hydrogen Bond Donors
NASA Astrophysics Data System (ADS)
Møller, Kristian H.; Tram, Camilla M.; Hansen, Anne S.; Kjaergaard, Henrik G.
2016-06-01
Hydroperoxides are formed in the atmosphere following autooxidation of a wide variety of volatile organics emitted from both natural and anthropogenic sources. This raises the question of whether they can form hydrogen bonds that facilitate aerosol formation and growth. Using a combination of Fourier transform infrared spectroscopy, FT-IR, and ab initio calculations, we have compared the gas phase hydrogen bonding ability of tert-butylhydroperoxide (tBuOOH) to that of tert-butanol (tBuOH) for a series of bimolecular complexes with different acceptors. The hydrogen bond acceptor atoms studied are nitrogen, oxygen, phosphorus and sulphur. Both in terms of calculated redshifts and binding energies (BE), our results suggest that hydroperoxides are better hydrogen bond donors than the corresponding alcohols. In terms of hydrogen bond acceptor ability, we find that nitrogen is a significantly better acceptor than the other three atoms, which are of similar strength. We observe a similar trend in hydrogen bond acceptor ability with other hydrogen bond donors including methanol and dimethylamine.
Chien, Shih-Hsiang; Chowdhury, Indranil; Hsieh, Ming-Kai; Li, Heng; Dzombak, David A; Vidic, Radisav D
2012-12-01
Secondary-treated municipal wastewater, an abundant and widely distributed impaired water source, is a promising alternative water source for thermoelectric power plant cooling. However, excessive biological growth is a major challenge associated with wastewater reuse in cooling systems as it can interfere with normal system operation as well as enhance corrosion and scaling problems. Furthermore, possible emission of biological aerosols (e.g., Legionella pneumophila) with the cooling tower drift can lead to public health concerns within the zone of aerosol deposition. In this study, the effectiveness of pre-formed and in-situ-formed monochloramine was evaluated for its ability to control biological growth in recirculating cooling systems using secondary-treated municipal wastewater as the only makeup water source. Bench-scale studies were compared with pilot-scale studies for their ability to predict system behavior under realistic process conditions. Effectiveness of the continuous addition of pre-formed monochloramine and monochloramine formed in-situ through the reaction of free chlorine with ammonia in the incoming water was evaluated in terms of biocide residual and its ability to control both planktonic and sessile microbial populations. Results revealed that monochloramine can effectively control biofouling in cooling systems employing secondary-treated municipal wastewater and has advantages relative to use of free chlorine, but that bench-scale studies seriously underestimate biocide dose and residual requirements for proper control of biological growth in full-scale systems. Pre-formed monochloramine offered longer residence time and more reliable performance than in-situ-formed monochloramine due to highly variable ammonia concentration in the recirculating water caused by ammonia stripping in the cooling tower. Pilot-scale tests revealed that much lower dosing rate was required to maintain similar total chlorine residual when pre-formed monochloramine was used as compared to in-situ-formed monochloramine. Adjustment of biocide dose to maintain monochloramine residual above 3mg/L is needed to achieve successful biological growth control in recirculating cooling systems using secondary-treated municipal effluent as the only source of makeup water. Copyright © 2012 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Zheng, C. Y.; Nie, F. L.; Zheng, Y. F.; Cheng, Y.; Wei, S. C.; Valiev, R. Z.
2011-08-01
Bulk ultrafine-grained Ni 50.8Ti 49.2 alloy (UFG-NiTi) was successfully fabricated by equal-channel angular pressing (ECAP) technique in the present study, and to further improve its surface biocompatibility, surface modification techniques including sandblasting, acid etching and alkali treatment were employed to produce either irregularly roughened surface or microporous surface or hierarchical porous surface with bioactivity. The effect of the above surface treatments on the surface roughness, wettability, corrosion behavior, ion release, apatite forming ability and cytocompatibility of UFG-NiTi alloy were systematically investigated with the coarse-grained NiTi alloy as control. The pitting corrosion potential ( Epit) was increased from 393 mV (SCE) to 704 mV (SCE) with sandblasting and further increased to 1539 mV (SCE) with following acid etching in HF/HNO 3 solution. All the above surface treatment increased the apatite forming ability of UFG-NiTi in varying degrees when soaked them in simulated body fluid (SBF). Meanwhile, both sandblasting and acid etching could promote the cytocompatibility for osteoblasts: sandblasting enhanced cell attachment and acid etching increased cell proliferation. The different corrosion behavior, apatite forming ability and cellular response of UFG-NiTi after different surface modifications are attributed to the topography and wettability of the resulting surface oxide layer.
Honda, Yoshitomo; Takeda, Yoshihiro; Li, Peiqi; Huang, Anqi; Sasayama, Satoshi; Hara, Eiki; Uemura, Naoya; Ueda, Mamoru; Hashimoto, Masanori; Arita, Kenji; Matsumoto, Naoyuki; Hashimoto, Yoshiya; Baba, Shunsuke; Tanaka, Tomonari
2018-04-11
Chemical modification of gelatin using epigallocatechin gallate (EGCG) promotes bone formation in vivo. However, further improvements are required to increase the mechanical strength and bone-forming ability of fabricated EGCG-modified gelatin sponges (EGCG-GS) for practical applications in regenerative therapy. In the present study, we investigated whether vacuum heating-induced dehydrothermal cross-linking of EGCG-GS enhances bone formation in critical-sized rat calvarial defects. The bone-forming ability of vacuum-heated EGCG-GS (vhEGCG-GS) and other sponges was evaluated by micro-computed tomography and histological staining. The degradation of sponges was assessed using protein assays, and cell morphology and proliferation were verified by scanning electron microscopy and immunostaining using osteoblastic UMR106 cells in vitro. Four weeks after the implantation of sponges, greater bone formation was detected for vhEGCG-GS than for EGCG-GS or vacuum-heated gelatin sponges (dehydrothermal cross-linked sponges without EGCG). In vitro experiments revealed that the relatively low degradability of vhEGCG-GS supports cell attachment, proliferation, and cell-cell communication on the matrix. These findings suggest that vacuum heating enhanced the bone forming ability of EGCG-GS, possibly via the dehydrothermal cross-linking of EGCG-GS, which provides a scaffold for cells, and by maintaining the pharmacological effect of EGCG.
Brandelli, Clara Lia Costa; Ribeiro, Vanessa Bley; Zimmer, Karine Rigon; Barth, Afonso Luís; Tasca, Tiana; Macedo, Alexandre José
2015-11-01
The traditional use of medicinal plants for treatment of infectious diseases by an indigenous Mbyá-Guarani tribe from South Brazil was assessed by evaluating the antibiotic and antibiofilm activities against relevant bacterial pathogens. Aqueous extracts from 10 medicinal plants were prepared according to indigenous Mbyá-Guarani traditional uses. To evaluate antibiotic (OD600) and antibiofilm (crystal violet method) activities, Pseudomonas aeruginosa ATCC 27853, Staphylococcus epidermidis ATCC 35984 and seven multi-drug resistant Klebsiella pneumoniae carbapenemase (KPC)-producing bacterial clinical isolates were challenged with the extracts. Furthermore, the susceptibility profile of KPC-producing bacteria and the ability of these isolates to form biofilm were evaluated. The plants Campomanesia xanthocarpa, Maytenus ilicifolia, Bidens pilosa and Verbena sp. showed the best activity against bacterial growth and biofilm formation. The majority of KPC-producing isolates, which showed strong ability to form biofilm and a multidrug resistance profile, was inhibited by more than 50% by some extracts. The Enterobacter cloacae (KPC 05) clinical isolate was the only one resistant to all extracts. This study confirms the importance of indigenous traditional medicinal knowledge and describes for the first time the ability of these plants to inhibit biofilm formation and/or bacterial growth of multi-drug resistant KPC-producing isolates.
Targeting melanoma stem cells with the Vitamin E derivative δ-tocotrienol.
Marzagalli, Monica; Moretti, Roberta Manuela; Messi, Elio; Marelli, Marina Montagnani; Fontana, Fabrizio; Anastasia, Alessia; Bani, Maria Rosa; Beretta, Giangiacomo; Limonta, Patrizia
2018-01-12
The prognosis of metastatic melanoma is very poor, due to the development of drug resistance. Cancer stem cells (CSCs) may play a crucial role in this mechanism, contributing to disease relapse. We first characterized CSCs in melanoma cell lines. We observed that A375 (but not BLM) cells are able to form melanospheres and show CSCs traits: expression of the pluripotency markers SOX2 and KLF4, higher invasiveness and tumor formation capability in vivo with respect to parental adherent cells. We also showed that a subpopulation of autofluorescent cells expressing the ABCG2 stem cell marker is present in the A375 spheroid culture. Based on these data, we investigated whether δ-TT might target melanoma CSCs. We demonstrated that melanoma cells escaping the antitumor activity of δ-TT are completely devoid of the ability to form melanospheres. In contrast, cells that escaped vemurafenib treatment show a higher ability to form melanospheres than control cells. δ-TT also induced disaggregation of A375 melanospheres and reduced the spheroidogenic ability of sphere-derived cells, reducing the expression of the ABCG2 marker. These data demonstrate that δ-TT exerts its antitumor activity by targeting the CSC subpopulation of A375 melanoma cells and might represent a novel chemopreventive/therapeutic strategy against melanoma.
ERIC Educational Resources Information Center
Hollingsworth, Jan Carter
2007-01-01
Challenger Baseball, a Division of Little League International, was established in 1989 with the first team forming in Bristol, Connecticut. Today, over 35,000 children with disabilities who are between the ages of 5 and 18 participate. Teams are formed according to abilities, rather than chronological age, and can include as many as 15 to 20…
Factor Structure Consistency in the Bruininks-Oseretsky Test--Short Form.
ERIC Educational Resources Information Center
Broadhead, Geoffrey D.; Bruininks, Robert H.
1983-01-01
The underlying structure of the motor abilities represented by the "Short Form of the Bruininks-Oseretsky Test of Motor Proficiency," along with the consistency of the emerging factors by sex and two chronological age (CA) levels, were studied with 765 nondisabled children 4.6 to 14.6 years old. (Author/SEW)
Pedagogical Conditions of Multilevel Foreign Languages Teaching in Pedagogical Higher Education
ERIC Educational Resources Information Center
Kadakin, Vasily V.; Shukshina, Tatiana I.; Piskunova, Svetlana I.; Babushkina, Larisa E.; Falileev, Alexander E.
2016-01-01
This article is devoted to pedagogical conditions of multilevel foreign languages teaching in pedagogical higher education. The purpose of the study is to form the students' skills in foreign language mastering, to form the ability to operate independently and autonomously in this activity, both in the specific learning situation, and in the…
Problem Solving Ability of Disadvantaged Children Under Four Test Modes.
ERIC Educational Resources Information Center
Houtz, John C.; And Others
A study was conducted to test the hypothesis that Ss from disadvantaged homes have poorly developed "abstract" thinking skills and that their thought can be characterized as more "concrete" or relational. Four forms of a problem-solving inventory were developed which differed in mode of presentation. The original form consisted of real-life…
Form and Functions: Publishing the Canadian Government "Weekly Checklist" on the Internet.
ERIC Educational Resources Information Center
Davies, Ron; Chalk, Tanis
1996-01-01
When a Canadian government documents listing was distributed over the Internet, differences were revealed in the design and implementation of print, FTP, Gopher and World Wide Web versions. Publishing form was found to affect: ability to provide specific editions for target audiences, amount of information delivered at one time, presentation…
Cyclopentadiene-mediated hydride transfer from rhodium complexes.
Pitman, C L; Finster, O N L; Miller, A J M
2016-07-12
Attempts to generate a proposed rhodium hydride catalytic intermediate instead resulted in isolation of (Cp*H)Rh(bpy)Cl (1), a pentamethylcyclopentadiene complex, formed by C-H bond-forming reductive elimination from the fleeting rhodium hydride. The hydride transfer ability of diene 1 was explored through thermochemistry and hydride transfer reactions, including the reduction of NAD(+).
ERIC Educational Resources Information Center
Pouyaud, Jacques; Vignoli, Emmanuelle; Dosnon, Odile; Lallemand, Noelle
2012-01-01
The CAAS-France Form consists of four scales, each with six items, which measure concern, control, curiosity, and confidence as psychosocial resources for managing occupational transitions, developmental tasks, and work traumas. Internal consistency estimates for the subscale and total scores ranged from moderate to good. The factor structure was…
Plasticity of Ability to Form Cross-Modal Representations in Infant Japanese Macaques
ERIC Educational Resources Information Center
Adachi, Ikuma; Kuwahata, Hiroko; Fujita, Kazuo; Tomonaga, Masaki; Matsuzawa, Tetsuro
2009-01-01
In a previous study, Adachi, Kuwahata, Fujita, Tomonaga & Matsuzawa demonstrated that infant Japanese macaques (Macaca fuscata) form cross-modal representations of conspecifics but not of humans. However, because the subjects in the experiment were raised in a large social group and had considerably less exposure to humans than to…
ERIC Educational Resources Information Center
Duarte, M. Eduarda; Soares, M. C.; Fraga, S.; Rafael, M.; Lima, M. R.; Paredes, I.; Agostinho, R.; Djalo, A.
2012-01-01
The Career-Adaptabilities Scale (CAAS)--Portugal Form consists of four scales, each with seven items, which measure concern, control, curiosity, and confidence as psychosocial resources for managing occupational transitions, developmental tasks, and work traumas. Internal consistency estimates for the subscale and total scores ranged from good to…
78 FR 9432 - Agency Forms Submitted for OMB Review, Request for Comments
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-08
... techniques or other forms of information technology. Comments to the RRB or OIRA must contain the OMB control... Report, to obtain an applicant's work history. This information is used by the RRB to determine the... on an annuitant's ability to work, the RRB needs the applicant's work history. The collection obtains...
Johannesen, Jason K; Lurie, Jessica B; Fiszdon, Joanna M; Bell, Morris D
2013-01-01
The Social Attribution Task-Multiple Choice (SAT-MC) uses a 64-second video of geometric shapes set in motion to portray themes of social relatedness and intentions. Considered a test of "Theory of Mind," the SAT-MC assesses implicit social attribution formation while reducing verbal and basic cognitive demands required of other common measures. We present a comparability analysis of the SAT-MC and the new SAT-MC-II, an alternate form created for repeat testing, in a university sample (n = 92). Score distributions and patterns of association with external validation measures were nearly identical between the two forms, with convergent and discriminant validity supported by association with affect recognition ability and lack of association with basic visual reasoning. Internal consistency of the SAT-MC-II was superior (alpha = .81) to the SAT-MC (alpha = .56). Results support the use of SAT-MC and new SAT-MC-II as equivalent test forms. Demonstrating relatively higher association to social cognitive than basic cognitive abilities, the SAT-MC may provide enhanced sensitivity as an outcome measure of social cognitive intervention trials.
Biofilm Formation by Pseudallescheria/Scedosporium Species: A Comparative Study.
Rollin-Pinheiro, Rodrigo; de Meirelles, Jardel V; Vila, Taissa V M; Fonseca, Beatriz B; Alves, Vinicius; Frases, Susana; Rozental, Sonia; Barreto-Bergter, Eliana
2017-01-01
Pseudallescheria/Scedosporium species are medically important fungi that are present in soil and human impacted areas and capable of causing a wide spectrum of diseases in humans. Although little is known about their pathogenesis, their growth process and infection routes are very similar to those of Aspergillus species, which grow as biofilms in invasive infections. All nine strains tested here displayed the ability to grow as biofilms in vitro and to produce a dense network of interconnected hyphae on both polystyrene and the surfaces of central venous catheters, but with different characteristics. Scedosporium boydii and S. aurantiacum clinical isolates were able to form biofilms faster than the corresponding environmental strains, as evidenced in kinetic assays for S. boydii and CLSM for S. aurantiacum . Biofilms formed by Pseudallescheria/Scedosporium species had significantly higher resistance to the class of antifungal azole than was observed in planktonic cells, indicating a protective role for this structure. In addition, the clinical S. aurantiacum isolate that formed the most robust biofilms was also more virulent in a larvae Galleria mellonella infection model, suggesting that the ability to form biofilms enhances virulence in Pseudallescheria/Scedosporium species.
The Limits of Cyberspace Deterrence
2014-01-01
networks are secure, this protection would also take the form of deterring, preventing, detect- ing, and defending against cyber attacks . As a result...tar- get into inaction. In a nuclear scenario, all nations are aware of the American ability to attribute a nuclear attack to its source, U.S...through degraded environment and improving ability to attribute and defeat attacks on systems and infrastructure. Military must provide broad range of
ERIC Educational Resources Information Center
Haebara, Tomokazu
When several ability scales in item response models are separately derived from different test forms administered to different samples of examinees, these scales must be equated to a common scale because their units and origins are arbitrarily determined and generally different from scale to scale. A general method for equating logistic ability…
ERIC Educational Resources Information Center
Cacola, Priscila; Roberson, Jerroed; Gabbard, Carl
2013-01-01
Studies show that as we enter older adulthood (greater than 64 years), our ability to mentally represent action in the form of using motor imagery declines. Using a chronometry paradigm to compare the movement duration of imagined and executed movements, we tested young-, middle-aged, and older adults on their ability to perform sequential finger…
Evans, Heather M.; Simpson, Andrew; Shen, Shu; Stromberg, Arnold J.; Pickett, Carol L.
2017-01-01
ABSTRACT The life cycle of the opportunistic fungal pathogen Pneumocystis murina consists of a trophic stage and an ascus-like cystic stage. Infection with the cyst stage induces proinflammatory immune responses, while trophic forms suppress the cytokine response to multiple pathogen-associated molecular patterns (PAMPs), including β-glucan. A targeted gene expression assay was used to evaluate the dendritic cell response following stimulation with trophic forms alone, with a normal mixture of trophic forms and cysts, or with β-glucan. We demonstrate that stimulation with trophic forms downregulated the expression of multiple genes normally associated with the response to infection, including genes encoding transcription factors. Trophic forms also suppressed the expression of genes related to antigen processing and presentation, including the gene encoding the major histocompatibility complex (MHC) class II transactivator, CIITA. Stimulation of dendritic cells with trophic forms, but not a mixture of trophic forms and cysts, reduced the expression of MHC class II and the costimulatory molecule CD40 on the surface of the cells. These defects in the expression of MHC class II and costimulatory molecules corresponded with a reduced capacity for trophic form-loaded dendritic cells to stimulate CD4+ T cell proliferation and polarization. These data are consistent with the delayed innate and adaptive responses previously observed in immunocompetent mice inoculated with trophic forms compared to responses in mice inoculated with a mixture of trophic forms and cysts. We propose that trophic forms broadly inhibit the ability of dendritic cells to fulfill their role as antigen-presenting cells. PMID:28694293
Hot metal gas forming of titanium grade 2 bent tubes
NASA Astrophysics Data System (ADS)
Paul, Alexander; Werner, Markus; Trân, Ricardo; Landgrebe, Dirk
2017-10-01
Within the framework of investigations, an exhaust gas component made of Titanium Grade 2 was produced by means of Hot Metal Gas Forming (HMGF) at the Fraunhofer IWU in Chemnitz, Germany. The semi-finished products were two-fold bent, thermal joined, calibrated and pre-formed tubes. So far, a three-stage internal high-pressure forming process at room temperature plus two necessary intermediate heat treatments were used to produce the component. Due to its complexity as well as the limited forming ability of Titanium Grade 2 at room temperature an one step Hot Metal Gas Forming was developed to replace the former procedure.
COMPUTER SIMULATION STUDY OF AMYLOID FIBRIL FORMATION BY PALINDROMIC SEQUENCES IN PRION PEPTIDES
Wagoner, Victoria; Cheon, Mookyung; Chang, Iksoo; Hall, Carol
2011-01-01
We simulate the aggregation of large systems containing palindromic peptides from the Syrian hamster prion protein SHaPrP 113–120 (AGAAAAGA) and the mouse prion protein MoPrP 111–120 (VAGAAAAGAV) and eight sequence variations: GAAAAAAG, (AG)4, A8, GAAAGAAA, A10, V10, GAVAAAAVAG, and VAVAAAAVAV The first two peptides are thought to act as the Velcro that holds the parent prion proteins together in amyloid structures and can form fibrils themselves. Kinetic events along the fibrillization pathway influence the types of structures that occur and variations in the sequence affect aggregation kinetics and fibrillar structure. Discontinuous molecular dynamics simulations using the PRIME20 force field are performed on systems containing 48 peptides starting from a random coil configuration. Depending on the sequence, fibrillar structures form spontaneously over a range of temperatures, below which amorphous aggregates form and above which no aggregation occurs. AGAAAAGA forms well organized fibrillar structures whereas VAGAAAAGAV forms less well organized structures that are partially fibrillar and partially amorphous. The degree of order in the fibrillar structure stems in part from the types of kinetic events leading up to its formation, with AGAAAAGA forming less amorphous structures early in the simulation than VAGAAAAGAV. The ability to form fibrils increases as the chain length and the length of the stretch of hydrophobic residues increase. However as the hydrophobicity of the sequence increases, the ability to form well-ordered structures decreases. Thus, longer hydrophobic sequences form slightly disordered aggregates that are partially fibrillar and partially amorphous. Subtle changes in sequence result in slightly different fibril structures. PMID:21557317
[Keeping company in an emotional trip. Emotional intelligence applied to the help relationship].
Conangla Marín, M Mercè
2004-03-01
In order to be a good professional and caretaker, it is essential to work on one's capacity to manage one's own feelings and emotions in an adaptable, intelligent manner. This set of abilities form part of the concept known as Emotional Intelligence. One can only give to another what one is and one knows how to give to oneself. The five ability groups which make up affective or emotional intelligence are: self-knowledge, self-control, self-motivation, empathy and relationship abilities. All are necessary in order to carry out good management of our feelings and emotions.
Information Processing from Infancy to 11 Years: Continuities and Prediction of IQ
Rose, Susan A.; Feldman, Judith F.; Jankowski, Jeffery J.; Van Rossem, Ronan
2012-01-01
This study provides the first direct evidence of cognitive continuity for multiple specific information processing abilities from infancy and toddlerhood to pre-adolescence, and provides support for the view that infant abilities and form the basis of later childhood abilities. Data from a large sample of children (N = 131) were obtained at five different time points (7, 12, 24, 36 months, and 11 years) for a large battery of tasks representing four cognitive domains (attention, processing speed, memory, and representational competence). Structural equation models of continuity were assessed for each domain, in which it was assumed that infant abilities → toddler abilities → 11-year abilities. Abilities at each age were represented by latent variables, which minimize task-specific variance and measurement error. The model for each domain fit the data. Moreover, abilities from the three age periods predicted global outcome, with infant, toddler, and contemporaneous 11-year measures, respectively, accounting for 12.3%, 18.5%, and 45.2% of the variance in 11-year IQ. These findings strengthen contentions that specific cognitive abilities that can be identified in infancy show long-term continuity and contribute importantly to later cognitive competence. PMID:23162179
Mallik, Dhriti; Pal, Shilpa; Ghosh, Anindya S
2018-04-01
AmpG permease is implicated both in beta-lactamase induction and peptidoglycan recycling in enterobacterial isolates. Here, physiological studies using molecular genetics show that deletion of AmpG permease dramatically increases beta-lactam susceptibility even in the presence of AmpC, TEM-1 and OXA beta-lactamases. Also, there is an appreciable decrease in the biofilm-forming ability of strains lacking this protein. Expression of this permease in excess probably compromises the integrity of the bacterial cells, leading to cell lysis. Based on these results, we propose that AmpG permease may be used as a potential antibiotic target and its suppression could efficiently inhibit both beta-lactamase induction and biofilm formation.
Cisowska, Agnieszka; Bugla-Płoskońska, Gabriela
2014-01-01
We used SDS-polyacrylamide gel electrophoresis to investigate the outer membrane proteins (OMPs) band composition of 19 Escherichia coli K1 strains that have spontaneously lost the ability to form K1 polysaccharide capsule (E. coli K1-) and demonstrated different degrees of susceptibility to the bactericidal action of normal human serum. Presented results showed that there were differences between E. coli K1- strains in OMPs expressing capacity. The analysis performed on OMPs has not revealed a direct association between the different OMPs band composition and the susceptibility of these strains to the serum.
Selective attention in normal and impaired hearing.
Shinn-Cunningham, Barbara G; Best, Virginia
2008-12-01
A common complaint among listeners with hearing loss (HL) is that they have difficulty communicating in common social settings. This article reviews how normal-hearing listeners cope in such settings, especially how they focus attention on a source of interest. Results of experiments with normal-hearing listeners suggest that the ability to selectively attend depends on the ability to analyze the acoustic scene and to form perceptual auditory objects properly. Unfortunately, sound features important for auditory object formation may not be robustly encoded in the auditory periphery of HL listeners. In turn, impaired auditory object formation may interfere with the ability to filter out competing sound sources. Peripheral degradations are also likely to reduce the salience of higher-order auditory cues such as location, pitch, and timbre, which enable normal-hearing listeners to select a desired sound source out of a sound mixture. Degraded peripheral processing is also likely to increase the time required to form auditory objects and focus selective attention so that listeners with HL lose the ability to switch attention rapidly (a skill that is particularly important when trying to participate in a lively conversation). Finally, peripheral deficits may interfere with strategies that normal-hearing listeners employ in complex acoustic settings, including the use of memory to fill in bits of the conversation that are missed. Thus, peripheral hearing deficits are likely to cause a number of interrelated problems that challenge the ability of HL listeners to communicate in social settings requiring selective attention.
Selective Attention in Normal and Impaired Hearing
Shinn-Cunningham, Barbara G.; Best, Virginia
2008-01-01
A common complaint among listeners with hearing loss (HL) is that they have difficulty communicating in common social settings. This article reviews how normal-hearing listeners cope in such settings, especially how they focus attention on a source of interest. Results of experiments with normal-hearing listeners suggest that the ability to selectively attend depends on the ability to analyze the acoustic scene and to form perceptual auditory objects properly. Unfortunately, sound features important for auditory object formation may not be robustly encoded in the auditory periphery of HL listeners. In turn, impaired auditory object formation may interfere with the ability to filter out competing sound sources. Peripheral degradations are also likely to reduce the salience of higher-order auditory cues such as location, pitch, and timbre, which enable normal-hearing listeners to select a desired sound source out of a sound mixture. Degraded peripheral processing is also likely to increase the time required to form auditory objects and focus selective attention so that listeners with HL lose the ability to switch attention rapidly (a skill that is particularly important when trying to participate in a lively conversation). Finally, peripheral deficits may interfere with strategies that normal-hearing listeners employ in complex acoustic settings, including the use of memory to fill in bits of the conversation that are missed. Thus, peripheral hearing deficits are likely to cause a number of interrelated problems that challenge the ability of HL listeners to communicate in social settings requiring selective attention. PMID:18974202
Murray C. Richardson; Carl P. J. Mitchell; Brian A. Branfireun; Randall K. Kolka
2010-01-01
A new technique for quantifying the geomorphic form of northern forested wetlands from airborne LiDAR surveys is introduced, demonstrating the unprecedented ability to characterize the geomorphic form of northern forested wetlands using high-resolution digital topography. Two quantitative indices are presented, including the lagg width index (LWI) which objectively...
The Development of Cortical Sensitivity to Visual Word Forms
ERIC Educational Resources Information Center
Ben-Shachar, Michal; Dougherty, Robert F.; Deutsch, Gayle K.; Wandell, Brian A.
2011-01-01
The ability to extract visual word forms quickly and efficiently is essential for using reading as a tool for learning. We describe the first longitudinal fMRI study to chart individual changes in cortical sensitivity to written words as reading develops. We conducted four annual measurements of brain function and reading skills in a heterogeneous…
READING PERFORMANCE OF ELEMENTARY STUDENT TEACHERS IN A DEVELOPING INSTITUTION.
ERIC Educational Resources Information Center
ADAMS, EFFIE KAYE
A STUDY WAS CONDUCTED AT BISHOP COLLEGE, DALLAS, TEXAS, TO EXAMINE THE READING NEEDS OF PROSPECTIVE ELEMENTARY TEACHERS. SCORES ON THE NELSON DENNY READING TESTS, ADVANCED FORM A, ON THE OTIS QUICK SCORING TESTS OF MENTAL ABILITY, GAMMA FORM BM, AND GRADE POINT AVERAGES COVERING 4 YEARS OF COLLEGE WORK WERE ANALYZED FOR 29 NEGRO ELEMENTARY STUDENT…
ERIC Educational Resources Information Center
Adams, Susan A.
2008-01-01
Development of a shame-based identity, also known as "toxic shame," can significantly interfere with an adult's ability to form an intimate relationship with another. As adults find peace from their past using transactional analysis and mental imagery, they learn to empower themselves to form healthy, intimate relationships.
Human Capital and Its Development in Present-Day Russia
ERIC Educational Resources Information Center
Nureev, R. M.
2010-01-01
In the broad sense of the word human capital is a specific form of capital that is embodied in people themselves. It consists of the individual's reserve of health, knowledge, skills, abilities, and motivations that enable him to increase his labor productivity and give him an income in the form of wages, salaries, and other income. The structure…
ERIC Educational Resources Information Center
Saito, Kazuya
2013-01-01
The present study examines whether and to what degree providing explicit phonetic information (EI) at the beginning of form-focused instruction (FFI) on second language pronunciation can enhance the generalizability and magnitude of FFI effectiveness by increasing learners' ability to notice a new phone. Participants were 49 Japanese learners of…
1991-03-01
forms: ". ..application blanks, biographical inventories , interviews, work sample tests, and intelligence, aptitude, and personality tests" (1:11...the grouping method, 3) the task method, and 4) the knowledge , skills, abilities (KSA) method. The point method of measuring training/experience assigns... knowledge , skills, abilities, and other characteristics which relate specifically to each job element (3:131). Interview. According to N. Schmitt
ERIC Educational Resources Information Center
Köksal, Mustafa Serdar
2016-01-01
The purposes of this study were to develop a culture specific critical thinking ability test for 6, 7, and 8. grade students in Turkey and to use it as an assessment instrument for giftedness. For these purposes, item pool involving 22 items was formed by writing items focusing on the current and common events presented in (Turkish) media from…
Laser-Based Acousto-Optic Uplink Communications Technique
2003-08-18
An apparatus for enabling acousto - optic communication comprising an in-water platform comprising means for emitting an acoustic signal to an acousto ...portion of the first interrogation beam and a second laser beam formed from the reflection of the first interrogation beam off of the acousto - optic interaction... optic interaction zone, an in-air platform comprising the ability for transmitting a first optical interrogation beam, the ability for receiving a
ERIC Educational Resources Information Center
Puhan, Gautam
2010-01-01
This study used real data to construct testing conditions for comparing results of chained linear, Tucker, and Levine-observed score equatings. The comparisons were made under conditions where the new- and old-form samples were similar in ability and when they differed in ability. The length of the anchor test was also varied to enable examination…
Parafati, Lucia; Vitale, Alessandro; Restuccia, Cristina; Cirvilleri, Gabriella
2015-05-01
Strains belonging to the species Saccharomyces cerevisiae, Wickerhamomyces anomalus, Metschnikowia pulcherrima and Aureobasidium pullulans, isolated from different food sources, were tested in vitro as biocontrol agents (BCAs) against the post-harvest pathogenic mold Botrytis cinerea. All yeast strains demonstrated antifungal activity at different levels depending on species and medium. Killer strains of W. anomalus and S. cerevisiae showed the highest biocontrol in vitro activity, as demonstrated by largest inhibition halos. The competition for iron and the ability to form biofilm and to colonize fruit wounds were hypothesized as the main action mechanisms for M. pulcherrima. The production of hydrolytic enzymes and the ability to colonize the wounds were the most important mechanisms for biocontrol activity in A. pullulans and W. anomalus, which also showed high ability to form biofilm. The production of volatile organic compounds (VOCs) with in vitro and in vivo inhibitory effect on pathogen growth was observed for the species W. anomalus, S. cerevisiae and M. pulcherrima. Our study clearly indicates that multiple modes of action may explain as M. pulcherrima provide excellent control of postharvest botrytis bunch rot of grape. Copyright © 2014 Elsevier Ltd. All rights reserved.
Dual-species biofilm of Listeria monocytogenes and Escherichia coli on stainless steel surface.
de Grandi, Aline Zago; Pinto, Uelinton Manoel; Destro, Maria Teresa
2018-04-12
Listeria monocytogenes is a Gram-positive bacterium commonly associated with foodborne diseases. Due its ability to survive under adverse environmental conditions and to form biofilm, this bacterium is a major concern for the food industry, since it can compromise sanitation procedures and increase the risk of post-processing contamination. Little is known about the interaction between L. monocytogenes and Gram-negative bacteria on biofilm formation. Thus, in order to evaluate this interaction, Escherichia coli and L. monocytogenes were tested for their ability to form biofilms together or in monoculture. We also aimed to evaluate the ability of L. monocytogenes 1/2a and its isogenic mutant strain (ΔprfA ΔsigB) to form biofilm in the presence of E. coli. We assessed the importance of the virulence regulators, PrfA and σ B , in this process since they are involved in many aspects of L. monocytogenes pathogenicity. Biofilm formation was assessed using stainless steel AISI 304 #4 slides immersed into brain heart infusion broth, reconstituted powder milk and E. coli preconditioned medium at 25 °C. Our results indicated that a higher amount of biofilm was formed by the wild type strain of L. monocytogenes than by its isogenic mutant, indicating that prfA and sigB are important for biofilm development, especially maturation under our experimental conditions. The presence of E. coli or its metabolites in preconditioned medium did not influence biofilm formation by L. monocytogenes. Our results confirm the possibility of concomitant biofilm formation by L. monocytogenes and E. coli, two bacteria of major significance in the food industry.
Role of DNA secondary structures in fragile site breakage along human chromosome 10
Dillon, Laura W.; Pierce, Levi C. T.; Ng, Maggie C. Y.; Wang, Yuh-Hwa
2013-01-01
The formation of alternative DNA secondary structures can result in DNA breakage leading to cancer and other diseases. Chromosomal fragile sites, which are regions of the genome that exhibit chromosomal breakage under conditions of mild replication stress, are predicted to form stable DNA secondary structures. DNA breakage at fragile sites is associated with regions that are deleted, amplified or rearranged in cancer. Despite the correlation, unbiased examination of the ability to form secondary structures has not been evaluated in fragile sites. Here, using the Mfold program, we predict potential DNA secondary structure formation on the human chromosome 10 sequence, and utilize this analysis to compare fragile and non-fragile DNA. We found that aphidicolin (APH)-induced common fragile sites contain more sequence segments with potential high secondary structure-forming ability, and these segments clustered more densely than those in non-fragile DNA. Additionally, using a threshold of secondary structure-forming ability, we refined legitimate fragile sites within the cytogenetically defined boundaries, and identified potential fragile regions within non-fragile DNA. In vitro detection of alternative DNA structure formation and a DNA breakage cell assay were used to validate the computational predictions. Many of the regions identified by our analysis coincide with genes mutated in various diseases and regions of copy number alteration in cancer. This study supports the role of DNA secondary structures in common fragile site instability, provides a systematic method for their identification and suggests a mechanism by which DNA secondary structures can lead to human disease. PMID:23297364
Fukuda, Shinichi; Beheregaray, Simone; Hoshi, Sujin; Yamanari, Masahiro; Lim, Yiheng; Hiraoka, Takahiro; Yasuno, Yoshiaki; Oshika, Tetsuro
2013-12-01
To evaluate the ability of parameters measured by three-dimensional (3D) corneal and anterior segment optical coherence tomography (CAS-OCT) and a rotating Scheimpflug camera combined with a Placido topography system (Scheimpflug camera with topography) to discriminate between normal eyes and forme fruste keratoconus. Forty-eight eyes of 48 patients with keratoconus, 25 eyes of 25 patients with forme fruste keratoconus and 128 eyes of 128 normal subjects were evaluated. Anterior and posterior keratometric parameters (steep K, flat K, average K), elevation, topographic parameters, regular and irregular astigmatism (spherical, asymmetry, regular and higher-order astigmatism) and five pachymetric parameters (minimum, minimum-median, inferior-superior, inferotemporal-superonasal, vertical thinnest location of the cornea) were measured using 3D CAS-OCT and a Scheimpflug camera with topography. The area under the receiver operating curve (AUROC) was calculated to assess the discrimination ability. Compatibility and repeatability of both devices were evaluated. Posterior surface elevation showed higher AUROC values in discrimination analysis of forme fruste keratoconus using both devices. Both instruments showed significant linear correlations (p<0.05, Pearson's correlation coefficient) and good repeatability (ICCs: 0.885-0.999) for normal and forme fruste keratoconus. Posterior elevation was the best discrimination parameter for forme fruste keratoconus. Both instruments presented good correlation and repeatability for this condition.
Effect of edible sesame oil on growth of clinical isolates of Candida albicans.
Ogawa, Toshiko; Nishio, Junko; Okada, Shinobu
2014-07-01
Elderly individuals are at increased risk of oral thrush (oral candidiasis) due to decreased saliva secretion. Due to their antimicrobial properties, edible oils can be effective natural agents for oral care. The objective of the present study was to compare the effects of sesame oil, which is widely used for cooking in Asian countries, and two other edible oils on the growth of both mycelial and yeast forms of five clinical isolates of Candida albicans, a causative microorganism of oral thrush. We assessed the effect of each oil in concentrations of 0.078%, 0.156%, and 0.313% on growth of the mycelial forms of the clinical isolates over 24 hr using the crystal violet method. We also evaluated the effect of each oil on growth of the yeast forms by counting the number of viable yeast cells after culturing in the oils for 24 hr. Sesame oil inhibited the growth of both mycelial and yeast forms. Safflower and olive oil also inhibited the growth of both forms of C. albicans but to a lesser extent than sesame oil. The ability to inhibit the growth of the mycelial form correlated with sesame oil concentration. Roasting influenced growth inhibition ability and high-roasted sesame oil most effectively inhibited the yeast form. The growth inhibitory effect differed among the five isolates. We hypothesize that the sesamin and fatty acid components of sesame oil are involved in its antifungal activity. © The Author(s) 2013.
Analysis of students’ self-determination in learning mathematics
NASA Astrophysics Data System (ADS)
Wilujeng, H.
2018-01-01
Self-determination (SDT) is the ability in identifying and achieving the purpose based on knowledge and the assessment of the individual against himself. Three aspects in the SDT includes autonomy, competence and relationships become an important part for students to be able to understand the capabilities of themselves, having a positive competitiveness to other students and can interact well between friends. Therefore, teachers need to know the ability of students SDT after making the learning process. This research was conducted to improve the process of learning mathematics by knowing the ability of students SDT. The researcher gave the question form to 38 students and analyzed the ability of SDT. The Results of the study showed that the student SDT ability is still poor. Students were lack of confidence to solve math problems. In addition, the competitiveness of students was low that have made them looked lazy. This can be resolved by making learning more interesting for students so that it can increase the student SDT ability.
Reproductive efficiency and shade avoidance plasticity under simulated competition.
Fazlioglu, Fatih; Al-Namazi, Ali; Bonser, Stephen P
2016-07-01
Plant strategy and life-history theories make different predictions about reproductive efficiency under competition. While strategy theory suggests under intense competition iteroparous perennial plants delay reproduction and semelparous annuals reproduce quickly, life-history theory predicts both annual and perennial plants increase resource allocation to reproduction under intense competition. We tested (1) how simulated competition influences reproductive efficiency and competitive ability (CA) of different plant life histories and growth forms; (2) whether life history or growth form is associated with CA; (3) whether shade avoidance plasticity is connected to reproductive efficiency under simulated competition. We examined plastic responses of 11 herbaceous species representing different life histories and growth forms to simulated competition (spectral shade). We found that both annual and perennial plants invested more to reproduction under simulated competition in accordance with life-history theory predictions. There was no significant difference between competitive abilities of different life histories, but across growth forms, erect species expressed greater CA (in terms of leaf number) than other growth forms. We also found that shade avoidance plasticity can increase the reproductive efficiency by capitalizing on the early life resource acquisition and conversion of these resources into reproduction. Therefore, we suggest that a reassessment of the interpretation of shade avoidance plasticity is necessary by revealing its role in reproduction, not only in competition of plants.
Medaka embryonic stem cells are capable of generating entire organs and embryo-like miniatures.
Hong, Ni; He, Bei Ping; Schartl, Manfred; Hong, Yunhan
2013-03-01
Embryonic stem (ES) cells have the potency to produce many cell types of the embryo and adult body. Upon transplantation into early host embryos, ES cells are able to differentiate into various specialized cells and contribute to host tissues and organs of all germ layers. Here we present data in the fish medaka (Oryzias latipes) that ES cells have a novel ability to form extra organs and even embryo-like miniatures. Upon transplantation as individual cells according to the standard procedure, ES cells distributed widely to various organ systems of 3 germ layers. Upon transplantation as aggregates, ES cells were able to form extra organs, including the hematopoietic organ and contracting heart. We show that localized ES cell transplantation often led to the formation of extra axes that comprised essentially of either host cells or donor ES cells. These extra axes were associated with the head region of the embryo proper or formed at ectopic sites on the yolk sac. Surprisingly, certain ectopic axes were even capable of forming embryo-like miniatures. We conclude that ES cells have the ability to form entire organs and even embryo-like miniatures under proper environmental conditions. This finding points to a new possibility to generate ES cell-derived axes and organs.
The predictive value of aptitude assessment in laparoscopic surgery: a meta-analysis.
Kramp, Kelvin H; van Det, Marc J; Hoff, Christiaan; Veeger, Nic J G M; ten Cate Hoedemaker, Henk O; Pierie, Jean-Pierre E N
2016-04-01
Current methods of assessing candidates for medical specialties that involve laparoscopic skills suffer from a lack of instruments to assess the ability to work in a minimally invasive surgery environment. A meta-analysis was conducted to investigate whether aptitude assessment can be used to predict variability in the acquisition and performance of laparoscopic skills. PubMed, PsycINFO and Google Scholar were searched to November 2014 for published and unpublished studies reporting the measurement of a form of aptitude for laparoscopic skills. The quality of studies was assessed with QUADAS-2. Summary correlations were calculated using a random-effects model. Thirty-four studies were found to be eligible for inclusion; six of these studies used an operating room performance measurement. Laparoscopic skills correlated significantly with visual-spatial ability (r = 0.32, 95% confidence interval [CI] 0.25-0.39; p < 0.001), perceptual ability (r = 0.31, 95% CI 0.22-0.39; p < 0.001), psychomotor ability (r = 0.26, 95% CI 0.10-0.40; p = 0.003) and simulator-based assessment of aptitude (r = 0.64, 95% CI 0.52-0.73; p < 0.001). Three-dimensional dynamic visual-spatial ability showed a significantly higher correlation than intrinsic static visual-spatial ability (p = 0.024). In general, aptitude assessments are associated with laparoscopic skill level. Simulator-based assessment of aptitude appears to have the potential to represent a job sample and to enable the assessment of all forms of aptitude for laparoscopic surgery at once. A laparoscopy aptitude test can be a valuable additional tool in the assessment of candidates for medical specialties that require laparoscopic skills. © 2016 John Wiley & Sons Ltd.
Zimmerman, Scott D; Lester Short, Glenda F; Hendrix, E Michael
2011-01-01
It remains unclear which classroom experiences, if any, foster critical think ability. We measured the effectiveness of interdisciplinary, case-based learning on the critical-thinking ability of graduate students enrolled in allied health care programs. We designed a voluntary classroom experience to examine the effectiveness of case studies used in an interdisciplinary setting to increase critical-thinking ability. Two groups of students were measured for their critical thinking ability using an online assessment both before and after their respective classroom experiences. One group of 14 graduate students from 4 different allied health care programs (interdisciplinary, ID) discussed complex interdisciplinary case studies and answered multiple-choice type questions formed around the cases. The second group was composed of graduate students (n = 28) from a single disciple enrolled in a clinical anatomy course (discipline specific, DS). They discussed complex case studies specific to their discipline and answered multiple-choice questions formed around the cases. There was no overall change in critical-thinking scores from the pre- to post-test in either group (delta scores: ID 1.5 ± 5.3, DS -1.7 ± 5.7). However, ID students scoring below the median on the pretest improved significantly (paired t-test, pre 50.7 ± 3.8, post 54.2 ± 1.7, p = 0.02). The interdisciplinary learning experience improved critical-thinking ability in students with the least proficiency. As case studies have long been used to advance deeper learning, these data provide evidence for a broader impact of cases when used in an interdisciplinary setting, especially for those students coming in with the least ability.
Rodgers, Vivien; Neville, Stephen; La Grow, Steven
2017-06-01
Satisfaction with life is a complex interplay of older people's perspectives on life achievements. Satisfaction with life, alongside health and functional ability contribute to successful ageing. To explore the impact of increasing age on older people's perceptions of their health, functional ability and life satisfaction. A cross-sectional survey of non-institutionalised older people (65+) was conducted (n = 542). The Short Form-12 Health Survey measured perceived physical and mental health, the Groningen Activity Restriction Scale measured functional ability and the Satisfaction With Life Scale measured life satisfaction. Significant group differences were found; while participants' perceptions of health and function decreased with age, perceptions of life satisfaction increased. Unexpectedly, the youngest groups reported low levels of life satisfaction while the oldest reported very high levels. Further study should consider factors that might influence the perception of health, functional ability and particularly life satisfaction across older age groups.
Wathoni, Nasrul; Motoyama, Keiichi; Higashi, Taishi; Okajima, Maiko; Kaneko, Tatsuo; Arima, Hidetoshi
2017-05-01
Curcumin is one of promising agents to accelerate the wound-healing process. However, the efficacy of curcumin is limited due to its poor water solubility and stability. To enhance the properties of curcumin, 2-hydroxypropyl-γ-cyclodextrin (HP-γ-CyD) can be used through complexation. Recently, we revealed that sacran has the potential to form a hydrogel film (HGF) as a wound dressing material. Therefore, in the present study, we investigated the wound healing ability of curcumin/HP-γ-CyD (Cur/HP-γ-CyD) complex in sacran-based HGF (Sac-HGF). We prepared the Cur/HP-γ-CyD complex in Sac-HGF without surface roughness. Additionally, the amorphous form in the Cur/HP-γ-CyD complex in Sac-HGF were observed. In contrast, the curcumin in Sac-HGF and curcumin/HP-γ-CyD physical mixture in Sac-HGF formed inhomogeneous films due to crystallization of curcumin. Furthermore, HP-γ-CyD played an important role to increase the elastic modulus of the Sac-HGF with high re-swelling ability. The Cur/HP-γ-CyD complex in Sac-HGF maintained antioxidant properties of curcumin. Curcumin was gradually released from the HP-γ-CyD complex in Sac-HGF. Notably, the Cur/HP-γ-CyD complex in Sac-HGF provided the highest wound healing ability in hairless mice. These results suggest that the Cur/HP-γ-CyD complex in Sac-HGF has the potential for use as a new transdermal therapeutic system to promote the wound-healing process. Copyright © 2017 Elsevier B.V. All rights reserved.
Behavioural evidence for distinct mechanisms related to global and biological motion perception.
Miller, Louisa; Agnew, Hannah C; Pilz, Karin S
2018-01-01
The perception of human motion is a vital ability in our daily lives. Human movement recognition is often studied using point-light stimuli in which dots represent the joints of a moving person. Depending on task and stimulus, the local motion of the single dots, and the global form of the stimulus can be used to discriminate point-light stimuli. Previous studies often measured motion coherence for global motion perception and contrasted it with performance in biological motion perception to assess whether difficulties in biological motion processing are related to more general difficulties with motion processing. However, it is so far unknown as to how performance in global motion tasks relates to the ability to use local motion or global form to discriminate point-light stimuli. Here, we investigated this relationship in more detail. In Experiment 1, we measured participants' ability to discriminate the facing direction of point-light stimuli that contained primarily local motion, global form, or both. In Experiment 2, we embedded point-light stimuli in noise to assess whether previously found relationships in task performance are related to the ability to detect signal in noise. In both experiments, we also assessed motion coherence thresholds from random-dot kinematograms. We found relationships between performances for the different biological motion stimuli, but performance for global and biological motion perception was unrelated. These results are in accordance with previous neuroimaging studies that highlighted distinct areas for global and biological motion perception in the dorsal pathway, and indicate that results regarding the relationship between global motion perception and biological motion perception need to be interpreted with caution. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Velázquez-Guadarrama, Norma; Olivares-Cervantes, Alma L; Salinas, Eva; Martínez, Leticia; Escorcia, Magdalena; Oropeza, Ricardo; Rosas, Irma
Coagulase-positive staphylococci (CoPS) are opportunistic pathogens carrying various mechanisms of resistance that have a large number of virulence factors, and whose ability to induce illness is associated with the host. This study aimed to investigate the presence of environmental coagulase-positive staphylococci, their susceptibility profile, clonal relationship and ability to form biofilm. The 16S rRNA genes from CoPS isolates were analyzed, and their antibiotic susceptibility was evaluated using the agar dilution method in accordance with Clinical and Laboratory Standards Institute guidelines. The clonal profile was obtained by pulsed-field gel electrophoresis (PFGE) and biofilm formation was measured by a crystal violet retention assay. A total of 72 Staphylococcus spp. strains were isolated from air, metal surfaces, and nostrils from humans, dogs, cats, and birds. Three species were identified: Staphylococcus aureus (17%), Staphylococcus intermedius (63%), and Staphylococcus pseudintermedius (21%). Ninety three percent (93%) of the strains were resistant to at least one of 13 tested antibiotics. S. pseudintermedius strains were the only resistant ones to methicillin while most of these isolates were multidrug-resistant, had significantly higher ability to form biofilm and PFGE grouped into seven different patterns, without showing clonal dispersion among animals and environmental isolates. This study suggests that dogs, cat, and air are environmental sources potentially carrying multidrug-resistant S. pseudintermedius, which survives in different environments through biofilm formation and multidrug resistance, characteristics that can be transmitted horizontally to other bacteria and exacerbate the problem of antibiotic resistance in humans. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.
Funnell, Elaine; Wilding, John
2011-02-01
We report a longitudinal study of an exceptional child (S.R.) whose early-acquired visual agnosia, following encephalitis at 8 weeks of age, did not prevent her from learning to construct an increasing vocabulary of visual object forms (drawn from different categories), albeit slowly. S.R. had problems perceiving subtle differences in shape; she was unable to segment local letters within global displays; and she would bring complex scenes close to her eyes: a symptom suggestive of an attempt to reduce visual crowding. Investigations revealed a robust ability to use the gestalt grouping factors of proximity and collinearity to detect fragmented forms in noisy backgrounds, compared with a very weak ability to segment fragmented forms on the basis of contrasts of shape. When contrasts in spatial grouping and shape were pitted against each other, shape made little contribution, consistent with problems in perceiving complex scenes, but when shape contrast was varied, and spatial grouping was held constant, S.R. showed the same hierarchy of difficulty as the controls, although her responses were slowed. This is the first report of a child's visual-perceptual development following very early neurological impairments to the visual cortex. Her ability to learn to perceive visual shape following damage at a rudimentary stage of perceptual development contrasts starkly with the loss of such ability in childhood cases of acquired visual agnosia that follow damage to the established perceptual system. Clearly, there is a critical period during which neurological damage to the highly active, early developing visual-perceptual system does not prevent but only impairs further learning.
Characterisation of cellulose films regenerated from acetone/water coagulants.
Geng, Hongjuan; Yuan, Zaiwu; Fan, Qingrui; Dai, Xiaonan; Zhao, Yue; Wang, Zhaojiang; Qin, Menghua
2014-02-15
A precooled aqueous solution of 7 wt% NaOH/12 wt% urea was used to dissolve cellulose up to a concentration of 2 wt%, which was then coagulated in an acetone/water mixture to regenerate cellulose film. The volume ratio of acetone to water (φ) had a dominant influence on film dimensional stability, film-forming ability, micromorphology, and mechanical strength. The film regenerated at φ=2.0 showed excellent performance in both dimensional stability and film-forming ability. Compared to that from pure acetone, the cellulose film from the acetone/water mixture with φ=2.0 was more densely interwoven, since the cellulosic fibrils formed during regeneration had pores with smaller average diameter. The alkali capsulated in the film during film formation could be released at quite a slow rate into the surrounding aqueous solution. The regenerated cellulose film with adjustable structure and properties may have potential applications in drug release and ultra filtration. Copyright © 2013 Elsevier Ltd. All rights reserved.
Asymmetric cellular memory in bacteria exposed to antibiotics.
Mathis, Roland; Ackermann, Martin
2017-03-09
The ability to form a cellular memory and use it for cellular decision-making could help bacteria to cope with recurrent stress conditions. We analyzed whether bacteria would form a cellular memory specifically if past events are predictive of future conditions. We worked with the asymmetrically dividing bacterium Caulobacter crescentus where past events are expected to only be informative for one of the two cells emerging from division, the sessile cell that remains in the same microenvironment and does not migrate. Time-resolved analysis of individual cells revealed that past exposure to low levels of antibiotics increases tolerance to future exposure for the sessile but not for the motile cell. Using computer simulations, we found that such an asymmetry in cellular memory could be an evolutionary response to situations where the two cells emerging from division will experience different future conditions. Our results raise the question whether bacteria can evolve the ability to form and use cellular memory conditionally in situations where it is beneficial.
Self-care of patients with diabetes mellitus cared for at an emergency service in Mexico.
Baquedano, Irasema Romero; dos Santos, Manoel Antônio; Martins, Tatiane Aparecida; Zanetti, Maria Lúcia
2010-01-01
This study examines the self-care ability of type 2 diabetes mellitus patients and relates it to sociodemographic and clinical variables. The study included 251 patients who were cared for by an emergency service in Mexico, in 2007. Data were obtained through structured interviews held at participants' households, through a form, a questionnaire and the Self-Care Ability Scale. Descriptive and correlation statistics were used for data analysis. The results show that 83 (33.5%) individuals displayed good self-care ability and 168 (66.5%) individuals displayed regular ability. A directly proportional correlation was found between self-care ability and schooling (r=0.124; p<0.05), as well as a negative correlation for religion (rs=-0.435; p<0.05) and duration of disease evolution (r=-0.667; p<0.05). The conclusion is that most of the individuals with type 2 diabetes mellitus displayed regular ability for self-care. Self-care ability is related to multiple variables that should be taken into account by health professionals when suggesting educational programs.
Functional Biomaterials: Solution Electrospinning and Gelation of Whey Protein and Pullulan
NASA Astrophysics Data System (ADS)
Sullivan, Stephanie Tolstedt
Utilizing biomaterials that are biodegradable, biocompatible and edible serve well for food products as well as biomedical applications. Biomaterials whey protein and pullulan both have these characteristics. Whey proteins (WP) have been used in food products for many years and more recently in pharmaceutical products. They have the ability to form both gels and stable foams. Pullulan (PULL) has also been used in both food and pharmaceutical products, and is a highly water soluble, non-gelling polysaccharide and has been used primarily as a film former. Herein, we investigate the ability of whey protein and pullulan to form nanofibers and gels. Combining their distinct properties allows the ability to uniquely manipulate nanofiber and gel characteristics and behavior for a variety of applications, from food to even tissue scaffolding. First, we determined the electrospinnability of aqueous whey protein solutions. Both whey protein isolate (WPI) and one of its major components beta--lactoglobulin (BLG), either in native or denatured form, yielded interesting micro and nanostructures when electrosprayed; while nanofiber production required blending with a spinnable polymer, poly(ethylene oxide) (PEO). WP:PEO solutions were also successfully electrospun at acidic pH (2≤pH≤3), which could improve shelf life. Fourier Transform Infrared Reflectance (FTIR) analysis of WP:PEO fiber mat indicated some variation in WP secondary structure with varying WPI concentration (as WPI increased, % alpha-helix increased and beta-turn decreased) and pH (as pH decreased from neutral (7.5) to acidic (2), % beta-sheet decreased and alpha-helix increased). X-ray Photoelectron Spectroscopy (XPS) also confirmed the presence of WP on the surface of the blend fibers, augmenting the FTIR analysis. Interestingly, WP:PEO composite nanofibers maintained its fibrous morphology at temperatures as high as 100 °C, above the 60 °C PEO melting point. Further, we show that the blend mats retained a fibrous structure after the heat treatment. Our second goal was to evaluate the ability of aqueous blends of whey protein and pullulan to form gels. We first looked at WP-PULL blend solutions at room temperature, finding an increasing linear trend in low shear viscosity as the relative concentration of pullulan increased. Blend solution samples were then heated to determine the ability of the blend solutions to form a gelled network. Starting with a homogeneous WP gel, adding PULL, at native mix or alkaline pH, maintained a transparent homogeneous microstructure, but resulted in weaker gels based on its response to stress. At WP isoelectric point (IEP) pH, both protein and blend gels became opaque due to protein aggregation, forming a particulate gel. All gels at the IEP were weaker, yielding at much lower stress and corresponding strain, due to the protein aggregation. The addition of transglutaminase enzyme yielded a stronger network than the native samples, while the addition of sodium trimetaphosphate salt yielded weaker gels and also induced relevant particle and/or course stranded microstructure in both pH 8 and IEP cases. The third part of this study demonstrated the ability of pullulan to form nanofibers in the solution electrospinning process. Aqueous pullulan solutions were able to form defect-free nanofibers with a minimum concentration of 15 w/w%. Pullulan and PULL:hydroxypropyl-beta- cyclodextrin (HPBCD) blend fibers were chemically crosslinked to form insoluble fibers using ethylene glycol diglycidyl ether (EGDGE), a chemical used in food contact coating applications. Next, solution blends of pullulan with whey protein were prepared and also electrospun at varying pH and relative biomaterial concentrations at 17 total w/w%. PULL-WP blend nanofiber mats were crosslinked via heat treatment and found to be both swellable and insoluble. When dried, the mats did not return to their original fiber state and instead appear to be gelatinous fibers in nature after soaking, and thereby making them potentially useful for tissue scaffolding applications. A fourth accomplishment was to utilize Near Infrared Reflectance (NIR) Spectroscopy and Chemometrics techniques to analyze commercial whey protein powder characteristics such as protein, fat and moisture content as well as pH. NIR has been utilized in the food and pharmaceutical industries for quality control as a valuable compliment to or replacement for more expensive testing such as High Performance Liquid Chromatography. Analysis resulted in the development of quantitative, linear regression models to correlate whey protein powder characteristics to NIR data. Whey protein's ability to form gels and pullulan's electrospinnability to form nanofibers is combined herein to form blends of both that can be changed with varying concentration, pH, temperature and supplementation with food-safe additives. The study correlates mechanical properties and microstructure of blend gels and nanofibers and provides a foundation for further study of swellable network for tissue application specifically in the use of pullulan-whey protein heat treated nanofiber mats.
Intrinsic and Extrinsic Temperature-Dependency of Viscosity-Sensitive Fluorescent Molecular Rotors
Howell, Sarah; Dakanali, Marianna; Theodorakis, Emmanuel A.; Haidekker, Mark A.
2011-01-01
Molecular rotors are a group of environment-sensitive fluorescent probes whose quantum yield depends on the ability to form twisted intramolecular chargetransfer (TICT) states. TICT formation is dominantly governed by the solvent's microviscosity, but polarity and the ability of the solvent to form hydrogen bonds play an additional role. The relationship between quantum yield ϕF and viscosity η is widely accepted as a power-law, ϕF = C · ηx. In this study, we isolated the direct influence of the temperature on the TICT formation rate by examining several molecular rotors in protic and aprotic solvents over a range of temperatures. Each solvent's viscosity was determined as a function of temperature and used in the above power-law to determine how the proportionality constant C varies with temperature. We found that the power-law relationship fully explains the variations of the measured steady-state intensity by temperature-induced variations of the solvent viscosity, and C can be assumed to be temperature-independent. The exponent x, however, was found to be significantly higher in aprotic solvents than in protic solvents. We conclude that the ability of the solvent to form hydrogen bonds has a major influence on the relationship between viscosity and quantum yield. To use molecular rotors for the quantitative determination of viscosity or microviscosity, the exponent x needs to be determined for each dye-solvent combination. PMID:21947609
Oetting, Janna B.
2017-01-01
Purpose We compared copula and auxiliary verb BE use by African American English–speaking children with and without a creole heritage, using Gullah/Geechee as the creole criterion, to determine if differences exist, the nature of the differences, and the impact of the differences on interpretations of ability. Method Data came from 38 children, aged 5 to 6 years (19 with Gullah/Geechee and 19 without Gullah/Geechee heritage). All were developing language typically, with groups matched on gender, maternal education, and, when possible, test scores. The children's productions of BE were elicited using a screener, probes, and language samples. Results Although many similarities were documented, the 2 groups' BE systems differed in 3 ways: use of unique forms (i.e., də), unique use of shared forms (i.e., BEEN), and rates of use of shared forms (e.g., am, is, was/were, was for were). Although most noticeable in the language samples, differences surfaced across tasks and showed the potential to affect interpretations of ability. Conclusions Dialect variation that is tied to children's creole heritage exists, involves 3 types of variation, and potentially affects interpretations of ability. Effects of a heritage language and different types of variation should be considered in research and clinical endeavors with African American English–speaking children. PMID:28796859
Van, Khai; Hides, Julie A; Richardson, Carolyn A
2006-12-01
Randomized controlled trial. To determine if the provision of visual biofeedback using real-time ultrasound imaging enhances the ability to activate the multifidus muscle. Increasingly clinicians are using real-time ultrasound as a form of biofeedback when re-educating muscle activation. The effectiveness of this form of biofeedback for the multifidus muscle has not been reported. Healthy subjects were randomly divided into groups that received different forms of biofeedback. All subjects received clinical instruction on how to activate the multifidus muscle isometrically prior to testing and verbal feedback regarding the amount of multifidus contraction, which occurred during 10 repetitions (acquisition phase). In addition, 1 group received visual biofeedback (watched the multifidus muscle contract) using real-time ultrasound imaging. All subjects were reassessed a week later (retention phase). Subjects from both groups improved their voluntary contraction of the multifidus muscle in the acquisition phase (P<.001) and the ability to recruit the multifidus muscle differed between groups (P<.05), with subjects in the group that received visual ultrasound biofeedback achieving greater improvements. In addition, the group that received visual ultrasound biofeedback retained their improvement in performance from week 1 to week 2 (P>.90), whereas the performance of the other group decreased (P<.05). Real-time ultrasound imaging can be used to provide visual biofeedback and improve performance and retention in the ability to activate the multifidus muscle in healthy subjects.
Pseudomonas aeruginosa uses T3SS to inhibit diabetic wound healing
Goldufsky, Josef; Wood, Stephen J.; Jayaraman, Vijayakumar; Majdobeh, Omar; Chen, Lin; Qin, Shanshan; Zhang, Chunxiang; DiPietro, Luisa A.; Shafikhani, Sasha H.
2015-01-01
Diabetic foot ulcers are responsible for more hospitalizations than any other complication of diabetes. Bacterial infection is recognized as an important factor associated with impaired healing in diabetic ulcers. Pseudomonas aeruginosa is the most frequently detected Gram-negative pathogen in diabetic ulcers. P. aeruginosa infection has been shown to impair healing in diabetic wounds in a manner that correlates with its ability to form biofilm. While the majority of infections in diabetic ulcers are biofilm associated, 33% of infections are nonbiofilm in nature. P. aeruginosa is the most prevalent Gram-negative pathogen in all diabetic wound types, which suggests that the deleterious impact of P. aeruginosa on healing in diabetic wounds goes beyond its ability to form biofilm and likely involves other factors. The Type III Secretion System (T3SS) virulence structure is required for the pathogenesis of all P. aeruginosa clinical isolates, suggesting that it may also play a role in the inhibition of wound repair in diabetic skin ulcers. We evaluated the role of T3SS in mediating P. aeruginosa–induced tissue damage in the wounds of diabetic mice. Our data demonstrate that P. aeruginosa establishes a robust and persistent infection in diabetic wounds independent of its ability to form biofilm and causes severe wound damage in a manner that primarily depends on its T3SS. PMID:25912785
Pseudomonas aeruginosa uses T3SS to inhibit diabetic wound healing.
Goldufsky, Josef; Wood, Stephen J; Jayaraman, Vijayakumar; Majdobeh, Omar; Chen, Lin; Qin, Shanshan; Zhang, Chunxiang; DiPietro, Luisa A; Shafikhani, Sasha H
2015-01-01
Diabetic foot ulcers are responsible for more hospitalizations than any other complication of diabetes. Bacterial infection is recognized as an important factor associated with impaired healing in diabetic ulcers. Pseudomonas aeruginosa is the most frequently detected Gram-negative pathogen in diabetic ulcers. P. aeruginosa infection has been shown to impair healing in diabetic wounds in a manner that correlates with its ability to form biofilm. While the majority of infections in diabetic ulcers are biofilm associated, 33% of infections are nonbiofilm in nature. P. aeruginosa is the most prevalent Gram-negative pathogen in all diabetic wound types, which suggests that the deleterious impact of P. aeruginosa on healing in diabetic wounds goes beyond its ability to form biofilm and likely involves other factors. The Type III Secretion System (T3SS) virulence structure is required for the pathogenesis of all P. aeruginosa clinical isolates, suggesting that it may also play a role in the inhibition of wound repair in diabetic skin ulcers. We evaluated the role of T3SS in mediating P. aeruginosa-induced tissue damage in the wounds of diabetic mice. Our data demonstrate that P. aeruginosa establishes a robust and persistent infection in diabetic wounds independent of its ability to form biofilm and causes severe wound damage in a manner that primarily depends on its T3SS. © 2015 by the Wound Healing Society.
Wilson, Ryan; Urraca, Nora; Skobowiat, Cezary; Hope, Kevin A; Miravalle, Leticia; Chamberlin, Reed; Donaldson, Martin; Seagroves, Tiffany N; Reiter, Lawrence T
2015-08-01
Dental pulp stem cells (DPSCs) provide an exciting new avenue to study neurogenetic disorders. DPSCs are neural crest-derived cells with the ability to differentiate into numerous tissues including neurons. The therapeutic potential of stem cell-derived lines exposed to culturing ex vivo before reintroduction into patients could be limited if the cultured cells acquired tumorigenic potential. We tested whether DPSCs that spontaneously immortalized in culture acquired features of transformed cells. We analyzed immortalized DPSCs for anchorage-independent growth, genomic instability, and ability to differentiate into neurons. Finally, we tested both spontaneously immortalized and human telomerase reverse transcriptase (hTERT)-immortalized DPSC lines for the ability to form tumors in immunocompromised animals. Although we observed increased colony-forming potential in soft agar for the spontaneously immortalized and hTERT-immortalized DPSC lines relative to low-passage DPSC, no tumors were detected from any of the DPSC lines tested. We noticed some genomic instability in hTERT-immortalized DPSCs but not in the spontaneously immortalized lines tested. We determined that immortalized DPSC lines generated in our laboratory, whether spontaneously or induced, have not acquired the potential to form tumors in mice. These data suggest cultured DPSC lines that can be differentiated into neurons may be safe for future in vivo therapy for neurobiological diseases. ©AlphaMed Press.
Maxwell, Jon P; Capio, Catherine M; Masters, Rich S W
2017-05-01
The benefits of implicit and explicit motor learning approaches in young adults have been studied extensively, but much less in children. This study investigated the relationship between fundamental motor ability and implicit/explicit learning in children using the errorless learning paradigm. First, the motor ability of 261 children (142 boys, 119 girls) aged 9-12 years (M = 9.74, SD = 0.67) was measured. Second, children with motor ability scores in the upper and lower quartile learned a golf-putting skill in either an errorless (implicit) or errorful (explicit) learning condition. Four groups were formed: Errorless High-Ability (n = 13), Errorless Low-Ability (n = 11), Errorful High-Ability (n = 10), and Errorful Low-Ability (n = 11). Learning consisted of 300 practice trials, while testing included a 50-trial retention test, followed by a 50-trial secondary task transfer test, and another 50-trial retention test. The results showed that for high- and low-ability errorless learners, motor performance was unaffected by the secondary task, as was the case for high-ability errorful learners. Low-ability errorful learners performed worse with a secondary task and were significantly poorer than the corresponding high-ability group. These results suggest that implicit motor learning (errorless) may be beneficial for children with low motor ability. The findings also show a trend that children of high motor ability might benefit from learning explicitly (errorful). Further research is recommended to examine the compatibility of implicit and explicit approaches for children of different abilities.
Development of instrument for assessing students’ critical and creative thinking ability
NASA Astrophysics Data System (ADS)
Herpiana, R.; Rosidin, U.
2018-01-01
The purpose of this study was to develop instruments to measure critical thinking ability and creative students in the topics of physics simple harmonic motion. The research method used was research development with application of procedures including research and data collection, planning, and initial product development. The participants of the study were thirty-four tenth grade students and five physics teachers of physics who were selected randomly from schools in the province of Lampung. The data collected by using test and analyzed in quantitative descriptive. Initial data showed that students’ critical and creative thinking ability were still low and instruments to assess students’ critical thinking skills and creative students was not yet available. Most of assessment conducted focused on memorization. Thus, the researchers developed a draft of instrument in the form of the test description based on criteria that encouraged students’ activity in understanding the concepts, strategies and decision/solution in dealing with problems. The development of the instrument was conducted considering real-world phenomena in the form of pictures and stories, description of the situation, and verbal presentation.
Salim, Maryem; Brodin, Elisabeth; Spaals-Abrahamsson, Yvonne; Berntorp, Erik; Zetterberg, Eva
2016-06-01
Nordic Walking is an exercise form requiring significant energy consumption, but where the use of poles minimizes the risk of injury. The aim of this pilot study was to examine the effect of 3 months of Nordic Walking on males (>40 years of age) with haemophilia, regarding joint function (Haemophilia Joint Health Score), physical ability (Haemophilia Exercise Project - Test-Questionnaire), exercise capacity (6-min walking test), pain (visual analogue scale) and quality of life (the Swedish version of The Short Form Health Survey, SF-36). Pre-interventional and post-interventional scores of above-mentioned parameters were analysed, using Wilcoxon Signed Ranks Test. Eleven participants were recruited to the study. Statistically significant improvements were observed in physical ability (P value: 0.01) and body perception (P value: 0.02). The intervention did not increase number of bleedings or factor consumption. This is the first study ever evaluating Nordic Walking in persons with haemophilia. Our results suggest that Nordic Walking is safe and efficient, also in patients with haemophilic arthropathy.
NASA Technical Reports Server (NTRS)
Thompson, Peter M.; Jones, William R., Jr.; Jansen, Mark J.; Prahl, Joseph M.
2000-01-01
A unique tribometer is used to study film forming and pressure supporting abilities of point contacts at zero entrainment velocity (ZEV). Film thickness is determined using a capacitance technique, verified through comparisons of experimental results and theoretical elastohydrodynamic lubrication (EHL) predictions for rolling contacts. Experiments are conducted using through hardened AISI 52 100 steel balls, Polyalphaolefin (PAO) 182 and Pentaerythritol Tetraheptanoate (PT) lubricants, and sliding speeds between 2.0 to 12.0 m/s. PAO 182 and PT are found to support pressures up to 1. 1 GPa and 0.67 GPa respectively. Protective lubricant films ranging in thickness between 90 to 2 10 nm for PAO 182 and 220 to 340 nm for PT are formed. Lubricants experience shear stresses between 14 to 22 MPa for PAO 182 and 7 to 16 MPa for PT at shear rates of 10(exp 7)/sec. The lubricant's pressure supporting ability most likely results from the combination of immobile films and its transition to a glassy solid at high pressures.
Lou, Yuanmei; Preobrazhenska, Olena; auf dem Keller, Ulrich; Sutcliffe, Margaret; Barclay, Lorena; McDonald, Paul C; Roskelley, Calvin; Overall, Christopher M; Dedhar, Shoukat
2008-10-01
Epithelial-mesenchymal transition (EMT) has been linked to metastatic propensity. The 4T1 tumor is a clinically relevant model of spontaneous breast cancer metastasis. Here we characterize 4T1-derived cell lines for EMT, in vitro invasiveness and in vivo metastatic ability. Contrary to expectations, 67NR cells, which form primary tumors but fail to metastasize, express vimentin and N-cadherin, but not E-cadherin. 4T1 cells express E-cadherin and ZO-1, but are migratory, invasive, and metastasize to multiple sites. 66cl4 cells form lung metastases and display a mixed phenotype, but are not as migratory or invasive as 67NR cells. These findings demonstrate that the metastatic ability of breast cancer cells does not strictly correlate with genotypic and phenotypic properties of EMT per se, and suggest that other processes may govern metastatic capability. Gene expression analysis of primary tumors did not identify differences in EMT markers, but did reveal candidate genes that may influence metastatic ability. Copyright (c) 2008 Wiley-Liss, Inc.
The Roles of APOBEC3G Complexes in the Incorporation of APOBEC3G into HIV-1
Zhang, Quan; Liu, Zhenlong; Jia, Pingping; Zhou, Jinming; Guo, Fei; You, Xuefu; Yu, Liyan; Zhao, Lixun; Jiang, Jiandong; Cen, Shan
2013-01-01
Background The incorporation of human APOBEC3G (hA3G) into HIV is required for exerting its antiviral activity, therefore the mechanism underlying hA3G virion encapsidation has been investigated extensively. hA3G was shown to form low-molecular-mass (LMM) and high-molecular-mass (HMM) complexes. The function of different forms of hA3G in its viral incorporation remains unclear. Methodology/Principal Findings In this study, we investigated the subcellular distribution and lipid raft association of hA3G using subcellular fractionation, membrane floatation assay and pulse-chase radiolabeling experiments respectively, and studied the correlation between the ability of hA3G to form the different complex and its viral incorporation. Our work herein provides evidence that the majority of newly-synthesized hA3G interacts with membrane lipid raft domains to form Lipid raft-associated hA3G (RA hA3G), which serve as the precursor of mature HMM hA3G complex, while a minority of newly-synthesized hA3G remains in the cytoplasm as a soluble LMM form. The distribution of hA3G among the soluble LMM form, the RA LMM form and the mature forms of HMM is regulated by a mechanism involving the N-terminal part of the linker region and the C-terminus of hA3G. Mutagenesis studies reveal a direct correlation between the ability of hA3G to form the RA LMM complex and its viral incorporation. Conclusions/Significance Together these data suggest that the Lipid raft-associated LMM A3G complex functions as the cellular source of viral hA3G. PMID:24098356
2016-12-01
five lower-order factors representing verbal, math , spatial, perceptual speed, and aviation knowledge, and a hierarchical general factor showed the...Academic Aptitude Verbal Quant. Verbal Analogies 25 X X X Arithmetic Reasoning 25 X X Word Knowledge 25 X X X Math Knowledge 25 X X...Reasoning (AR) uses word problems to assess the ability to understand arithmetic relations. Math Knowledge (MK) assesses the ability to use
Study of the glass formation of high temperature superconductors
NASA Technical Reports Server (NTRS)
Ethridge, Edwin C.; Kaukler, William F.; Rolin, Terry
1992-01-01
A number of compositions of ceramic oxide high T(sub c) superconductors were elevated for their glass formation ability by means of rapid thermal analysis during quenching, optical, and electron microscopy of the quenched samples, and with subsequent DSC measurements. Correlations between experimental measurements and the methodical composition changes identified the formulations of superconductors that can easily form glass. The superconducting material was first formed as a glass; then, with subsequent devitrification, it was formed into a bulk crystalline superconductor by a series of processing methods.
1999-01-01
AFFF ( aqueous film - forming foam ), is widely used by the U.S. Navy in fire fighting water to improve the ability to control petroleum...Chan, D. B., (1978). " Disposal of Wastewater Containing Aqueous Film Forming Foam ." Technical Memorandum No. M-54-78-06, Civil Engineering...Inmand, R.C. (1975). "Biodegradability and Toxicity of ANSUL K74-100, Aqueous Film Forming Foam ." Report No. EHL(K) 75-3, USAF Environmental
López, Daniel; Vlamakis, Hera; Kolter, Roberto
2010-07-01
The ability to form biofilms is a universal attribute of bacteria. Biofilms are multicellular communities held together by a self-produced extracellular matrix. The mechanisms that different bacteria employ to form biofilms vary, frequently depending on environmental conditions and specific strain attributes. In this review, we emphasize four well-studied model systems to give an overview of how several organisms form biofilms: Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus. Using these bacteria as examples, we discuss the key features of biofilms as well as mechanisms by which extracellular signals trigger biofilm formation.
Self-assembly of block copolymers on topographically patterned polymeric substrates
Russell, Thomas P.; Park, Soojin; Lee, Dong Hyun; Xu, Ting
2016-05-10
Highly-ordered block copolymer films are prepared by a method that includes forming a polymeric replica of a topographically patterned crystalline surface, forming a block copolymer film on the topographically patterned surface of the polymeric replica, and annealing the block copolymer film. The resulting structures can be used in a variety of different applications, including the fabrication of high density data storage media. The ability to use flexible polymers to form the polymeric replica facilitates industrial-scale processes utilizing the highly-ordered block copolymer films.
ERIC Educational Resources Information Center
Khusainova, Guzel R.; Galeeva, Farida T.; Giniyatullina, Diana R.; Tarasova, Natalya M.; Tsareva, Ekaterina E.
2016-01-01
This article is focused on the development of the organizational forms of future managers training for the development of their key competencies, namely, creativity and the ability to work in a team. The analysis of works of the researchers in the field of management and pedagogics shows that small groups as an organizational form has great…
14-Month-Old Infants Form Novel Word-Spatial Relation Associations
ERIC Educational Resources Information Center
Casasola, Marianella; Wilbourn, Makeba Parramore
2004-01-01
This study explored 14-month-old infants' ability to form novel word-spatial relation associations. During habituation, infants heard 1 novel word (e.g., "teek") while viewing dynamic containment events (i.e., Big Bird placed in a box) and, on other habituation trials, a second novel word (e.g., "blick") while viewing dynamic support events (i.e.,…
Export chip prices as a proxy for nonsawtimber prices in the Pacific Northwest.
Gwenlyn M. Busby
2006-01-01
Forest-land managers use price data and market analysis to form expectations and make informed management decisions. There is an abundance of price data for sawtimber, but for nonsawtimber, the availability of price data is limited. This constrains the ability of forest-land managers to form reasonable price expectations for stands that contain both sawtimber and...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shi, Rong; Munger, Christine; Asinas, Abdalin
2010-10-22
The crystal structure of the urease maturation protein UreE from Helicobacter pylori has been determined in its apo form at 2.1 {angstrom} resolution, bound to Cu{sup 2+} at 2.7 {angstrom} resolution, and bound to Ni{sup 2+} at 3.1 {angstrom} resolution. Apo UreE forms dimers, while the metal-bound enzymes are arranged as tetramers that consist of a dimer of dimers associated around the metal ion through coordination by His102 residues from each subunit of the tetramer. Comparison of independent subunits from different crystal forms indicates changes in the relative arrangement of the N- and C-terminal domains in response to metal binding.more » The improved ability of engineered versions of UreE containing hexahistidine sequences at either the N-terminal or C-terminal end to provide Ni{sup 2+} for the final metal sink (urease) is eliminated in the H102A version. Therefore, the ability of the improved Ni{sup 2+}-binding versions to deliver more nickel is likely an effect of an increased local concentration of metal ions that can rapidly replenish transferred ions bound to His102.« less
Johannesen, Jason K.; Lurie, Jessica B.; Fiszdon, Joanna M.; Bell, Morris D.
2013-01-01
The Social Attribution Task-Multiple Choice (SAT-MC) uses a 64-second video of geometric shapes set in motion to portray themes of social relatedness and intentions. Considered a test of “Theory of Mind,” the SAT-MC assesses implicit social attribution formation while reducing verbal and basic cognitive demands required of other common measures. We present a comparability analysis of the SAT-MC and the new SAT-MC-II, an alternate form created for repeat testing, in a university sample (n = 92). Score distributions and patterns of association with external validation measures were nearly identical between the two forms, with convergent and discriminant validity supported by association with affect recognition ability and lack of association with basic visual reasoning. Internal consistency of the SAT-MC-II was superior (alpha = .81) to the SAT-MC (alpha = .56). Results support the use of SAT-MC and new SAT-MC-II as equivalent test forms. Demonstrating relatively higher association to social cognitive than basic cognitive abilities, the SAT-MC may provide enhanced sensitivity as an outcome measure of social cognitive intervention trials. PMID:23864984
Stappert, Kathrin; Unal, Derya; Spielberg, Eike T.; ...
2014-11-25
The influence of the counteranion on the ability of the mesogenic cation 1-methyl-3-dodecyl-triazolium to form mesophases is explored. To that avail, salts of the cation with anions of different size, shape, and hydrogen bonding capability such as Cl –, Br –, I –, I 3 –, PF 6 –, and Tf 2N – [bis(trifluorosulfonyl)amide] were synthesized and characterized. The crystal structures of the bromide, the iodide, and the triiodide reveal that the cations form bilayers with cations oriented in opposite directions featuring interdigitated alkyl tails. Within the layers, the cations are separated by anions. The rod-shaped triiodide anion forces themore » triazolium cation to align with it in this crystal structure but due to its space requirement reduces the alkyl chain interdigitation which prevents the formation of a mesophase. Rather the compound transforms directly from a crystalline solid to an (ionic) liquid like the analogous bis(trifluorosulfonyl)amide. In contrast, the simple halides and the hexafluorophosphate form liquid crystalline phases. As a result, their clearing points shift with increasing anion radius to lower temperatures.« less
Biofilm Formation by Pseudallescheria/Scedosporium Species: A Comparative Study
Rollin-Pinheiro, Rodrigo; de Meirelles, Jardel V.; Vila, Taissa V. M.; Fonseca, Beatriz B.; Alves, Vinicius; Frases, Susana; Rozental, Sonia; Barreto-Bergter, Eliana
2017-01-01
Pseudallescheria/Scedosporium species are medically important fungi that are present in soil and human impacted areas and capable of causing a wide spectrum of diseases in humans. Although little is known about their pathogenesis, their growth process and infection routes are very similar to those of Aspergillus species, which grow as biofilms in invasive infections. All nine strains tested here displayed the ability to grow as biofilms in vitro and to produce a dense network of interconnected hyphae on both polystyrene and the surfaces of central venous catheters, but with different characteristics. Scedosporium boydii and S. aurantiacum clinical isolates were able to form biofilms faster than the corresponding environmental strains, as evidenced in kinetic assays for S. boydii and CLSM for S. aurantiacum. Biofilms formed by Pseudallescheria/Scedosporium species had significantly higher resistance to the class of antifungal azole than was observed in planktonic cells, indicating a protective role for this structure. In addition, the clinical S. aurantiacum isolate that formed the most robust biofilms was also more virulent in a larvae Galleria mellonella infection model, suggesting that the ability to form biofilms enhances virulence in Pseudallescheria/Scedosporium species. PMID:28868050
Environmental Regulation of Yersinia Pathophysiology
Chen, Shiyun; Thompson, Karl M.; Francis, Matthew S.
2016-01-01
Hallmarks of Yersinia pathogenesis include the ability to form biofilms on surfaces, the ability to establish close contact with eukaryotic target cells and the ability to hijack eukaryotic cell signaling and take over control of strategic cellular processes. Many of these virulence traits are already well-described. However, of equal importance is knowledge of both confined and global regulatory networks that collaborate together to dictate spatial and temporal control of virulence gene expression. This review has the purpose to incorporate historical observations with new discoveries to provide molecular insight into how some of these regulatory mechanisms respond rapidly to environmental flux to govern tight control of virulence gene expression by pathogenic Yersinia. PMID:26973818
Physiopathology and diagnosis of nephrogenic diabetes insipidus.
Devuyst, Olivier
2012-04-01
Nephrogenic diabetes insipidus (NDI) is caused by an improper response of the kidney to the antidiuretic hormone arginine vasopressin (AVP), leading to a decreased ability to concentrate urine which results in polyuria and polydipsia. The clinical diagnosis of NDI relies on demonstration of subnormal ability to concentrate urine despite the presence of AVP. NDI is most commonly acquired, secondary to kidney disorders, electrolyte imbalance and various drugs. Congenital forms of NDI are rare, and most commonly inherited in a X-linked manner with mutations of the AVP receptor type 2 (AVPR2). Mutations of the water channel aquaporin-2 (AQP2) can be detected in autosomal recessive or dominant forms of NDI. Management of NDI should focus on free access to drinking water and reduction of polyuria. Copyright © 2012 Elsevier Masson SAS. All rights reserved.
NASA Technical Reports Server (NTRS)
Buecker, H.; Horneck, G.; Wollenhaupt, H.
1973-01-01
Bacillus subtilis spores are highly resistant to harsh environments. Therefore, in the Apollo 16 Microbial Response to Space Environment Experiment (M191), these spores were exposed to space vacuum or solar ultraviolet irradiation, or both, to estimate the change of survival for terrestrial organisms in space. The survival of the spores was determined in terms of colony-forming ability. Comparison of the flight results with results of simulation experiments on earth applying high vacuum or ultraviolet irradiation, or both, revealed no remarkable difference. Simultaneous exposure to both these space factors resulted in a synergistic effect (that is, an ultraviolet supersensitivity). Therefore, the change of survival in space is assumed to depend on the degree of protection against solar ultraviolet irradiation.
Lovesey, E J
1970-06-01
In just over a decade the hovercraft has progressed from first prototype to a successful commercial form of transport which also has the ability to penetrate many environments hitherto virtually inaccessible to manned vehicles. Comparison with rival short range vehicles such as the helicopter and hydrofoil show that the hovercraft has become one of the most versatile forms of transport available. This versatility and ability to operate in unusual or extreme environments has been accompanied by the problems of control and of protection of the occupants of the hovercraft from the hazards associated with these environments. Several of these problems are discussed, together with their possible solutions. This article is based on a paper given to the Nederlands Vereniging Voor Ergonomie/Ergonomics Research Society joint conference at Noordwijk in Holland, 11-13 June, 1969.
Kottom, Theodore J.; Hebrink, Deanne M.; Jenson, Paige E.; Ramirez-Prado, Jorge H.
2017-01-01
N-acetylglucosamine (GlcNAc) serves as an essential structural sugar on the cell surface of organisms. For example, GlcNAc is a major component of bacterial peptidoglycan, it is an important building block of fungal cell walls, including a major constituent of chitin and mannoproteins, and it is also required for extracellular matrix generation by animal cells. Herein, we provide evidence for a uridine diphospho (UDP)–GlcNAc pathway in Pneumocystis species. Using an in silico search of the Pneumocystis jirovecii and P. murina (Pm) genomic databases, we determined the presence of at least four proteins implicated in the Saccharomyces cerevisiae UDP-GlcNAc biosynthetic pathway. These genes, termed GFA1, GNA1, AGM1, and UDP-GlcNAc pyrophosphorylase (UAP1), were either confirmed to be present in the Pneumocystis genomes by PCR, or, in the case of Pm uap1 (Pmuap1), functionally confirmed by direct enzymatic activity assay. Expression analysis using quantitative PCR of Pneumocystis pneumonia in mice demonstrated abundant expression of the Pm uap1 transcript. A GlcNAc-binding recombinant protein and a novel GlcNAc-binding immune detection method both verified the presence of GlcNAc in P. carinii (Pc) lysates. Studies of Pc cell wall fractions using high-performance gas chromatography/mass spectrometry documented the presence of GlcNAc glycosyl residues. Pc was shown to synthesize GlcNAc in vitro. The competitive UDP-GlcNAc substrate synthetic inhibitor, nikkomycin Z, suppressed incorporation of GlcNAc by Pc preparations. Finally, treatment of rats with Pneumocystis pneumonia using nikkomycin Z significantly reduced organism burdens. Taken together, these data support an important role for GlcNAc generation in the cell surface of Pneumocystis organisms. PMID:27632412
NASA Astrophysics Data System (ADS)
Santos-Filho, Osvaldo A.; Mishra, Rama K.; Hopfinger, A. J.
2001-09-01
Free energy force field (FEFF) 3D-QSAR analysis was used to construct ligand-receptor binding models for a set of 18 structurally diverse antifolates including pyrimethamine, cycloguanil, methotrexate, aminopterin and trimethoprim, and 13 pyrrolo[2,3-d]pyrimidines. The molecular target (`receptor') used was a 3D-homology model of a specific mutant type of Plasmodium falciparum (Pf) dihydrofolate reductase (DHFR). The dependent variable of the 3D-QSAR models is the IC50 inhibition constant for the specific mutant type of PfDHFR. The independent variables of the 3D-QSAR models (the descriptors) are scaled energy terms of a modified first-generation AMBER force field combined with a hydration shell aqueous solvation model and a collection of 2D-QSAR descriptors often used in QSAR studies. Multiple temperature molecular dynamics simulation (MDS) and the genetic function approximation (GFA) were employed using partial least square (PLS) and multidimensional linear regressions as the fitting functions to develop FEFF 3D-QSAR models for the binding process. The significant FEFF energy terms in the best 3D-QSAR models include energy contributions of the direct ligand-receptor interaction. Some changes in conformational energy terms of the ligand due to binding to the enzyme are also found to be important descriptors. The FEFF 3D-QSAR models indicate some structural features perhaps relevant to the mechanism of resistance of the PfDHFR to current antimalarials. The FEFF 3D-QSAR models are also compared to receptor-independent (RI) 4D-QSAR models developed in an earlier study and subsequently refined using recently developed generalized alignment rules.
Code of Federal Regulations, 2010 CFR
2010-10-01
... process, established and documented by the operator, to determine an individual's ability to perform a...) Simulations; (e) Other forms of assessment. Qualified means that an individual has been evaluated and can: (a...
Valverde, Juan Manuel; Rodríguez, Karina; Herrera, María; Segura, Álvaro; Vargas, Mariángela; Villalta, Mauren; Montero, Mavis; Gutiérrez, Jose María; León, Guillermo
2017-03-01
Adjuvant emulsions are widely used to enhance the antibody response of the animals used as immunoglobulin source for producing antivenoms. Usually, the adjuvant activity of emulsions is attributed both to their ability to trigger "danger" signals from cells in which they induce death, and to form depots from which immunogens are slowly released. However, there is contradictory evidence suggesting that adjuvant activity of emulsions is independent of the dispersion type and the rate of immunogen release. In order to test how physical properties of emulsions, composed of mineral oil and water, affect their ability to enhance the antibody response towards snake venoms, we compared water-in-oil (W/O) emulsions prepared at volume ratios of 70/30, 50/50 or 30/70, a 50/50 oil-in-water (O/W) emulsion, and a water-in-oil-in-water (W/O/W) multiple emulsion. Comparison included their droplet-size, viscosity, rate of immunogen release and ability to enhance the antibody response of mice immunized with the venom of the African viperid snake Echis ocellatus. It was found that all emulsions released a low amount of venom, and that the 50/50 (W/O) and the multiple emulsion (W/O/W) were those that induced the higher anti-venom antibody response. Our results suggest that the ability of emulsions to enhance the anti-venom response is not associated to their ability to form depots from which the venom is slowly released. Copyright © 2017 Elsevier Ltd. All rights reserved.
Neri, Luca; Rocca Rey, Luisa A; Gallieni, Maurizio; Brancaccio, Diego; Cozzolino, Mario; Colombi, Antonio; Burroughs, Thomas E
2009-05-01
About 300,000 patients in the United States with Chronic Kidney Failure (CKF) are of working age, but up to 70% lose their job within the first year of renal replacement therapy .No study has examined how work ability and perceived health are influenced by the subjects' adjustment to their job. We assessed the association of occupational stress (Effort-Reward Imbalance, ERI),work ability (WAI) and health-related quality of life (QoL) in hemodialysis. 40 employed hemodialysis patients completed a self-administered questionnaire. Associations between ERI, short Form 12 (sF-12), short Form - 6 Dimensions (sF-6D), Kidney Disease QOL- 36 (KDQOL-36) and WAI were tested with partial Spearman's correlation adjusted for age, income, and comorbidity burden. Study subjects were mainly low-income (82%), african-american (73%), men (75%); 16 were manual laborers and 9 worked in the industrial sector. Study subjects reported low levels of Occupational Stress: ERI scores indicated an imbalance between Job Efforts and Rewards in only 3 subjects. Nevertheless, ERI scores were inversely and strongly associated with WAI (rho=-0.41, p<0.012) and all QoL scales even after adjustment for known confounders. Our study suggests that psychosocial workplace factors may play a substantial role in modulating patients' health perception and ability to continue working. The causal relationship between Occupational stress, perceived health, and work ability should be further investigated. Occupational Health professionals and nephrologists should closely collaborate to meet the needs of occupationally active hemodialysis patients.
Yamamoto, S; Han, L; Noiri, Y; Okiji, T
2017-12-01
To evaluate the Ca 2+ -releasing, alkalizing and apatite-like surface precipitate-forming abilities of a prototype tricalcium silicate cement, which was mainly composed of synthetically prepared tricalcium silicate and zirconium oxide radiopacifier. The prototype tricalcium silicate cement, white ProRoot MTA (WMTA) and TheraCal LC (a light-cured resin-modified calcium silicate-filled material) were examined. The chemical compositions were analysed with a wavelength-dispersive X-ray spectroscopy electron probe microanalyser with an image observation function (SEM-EPMA). The pH and Ca 2+ concentrations of water in which the set materials had been immersed were measured, and the latter was assessed with the EDTA titration method. The surface precipitates formed on the materials immersed in phosphate-buffered saline (PBS) were analysed with SEM-EPMA and X-ray diffraction (XRD). Kruskal-Wallis tests followed by Mann-Whitney U-test with Bonferroni correction were used for statistical analysis (α = 0.05). The prototype cement contained Ca, Si and Zr as major elemental constituents, whereas it did not contain some metal elements that were detected in the other materials. The Ca 2+ concentrations and pH of the immersion water samples exhibited the following order: WMTA = prototype cement > TheraCal LC (P < 0.05). All three materials produced Ca- and P-containing surface precipitates after PBS immersion, and the precipitates produced by TheraCal LC displayed lower Ca/P ratios than those formed by the other materials. XRD peaks corresponding to hydroxyapatite were detected in the precipitates produced by the prototype cement and WMTA. The prototype tricalcium silicate cement exhibited similar Ca 2+ -releasing, alkalizing and apatite-like precipitate-forming abilities to WMTA. The Ca 2+ -releasing, alkalizing and apatite-like precipitate-forming abilities of TheraCal LC were lower than those of the other materials. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.
Eskola, M; Bäckman, S; Möttönen, S; Kekomäki, R
2015-04-01
Total colony-forming cells from thawed cord blood units (CBUs) include megakaryocytic colony-forming units (CFU-Mks), which survive the freezing process. The aim of this study was to evaluate whether different megakaryocytic progenitors from unseparated CBUs survive the freezing process and a short-term liquid culture. Thawed samples of CBUs were cultured in liquid medium. During the cultures, serial samples were drawn to assess the growth of different megakaryocytic progenitors in a semisolid collagen medium with identical cytokines as in the liquid medium. Megakaryocytic cells were detected using immunohistochemistry and flow cytometry. In suspension culture, the megakaryocytic progenitors almost completely lost the ability to generate large (burst-forming unit-like, BFU-like) megakaryocytic colonies in semisolid cultures (large colonies, median count per chamber d0: 7.25 vs. d7: 1.5; P < 0.0001), whereas the number of small colonies (median count per chamber d0: 7.25 vs. d7: 16.0; P = 0.0505) peaked at day seven. Further 7-day culture in suspension resulted in the decline of small colonies as well (d7: 16.0 vs. d14: 5.75; P = 0.0088). Total CFU-Mk count declined from 23.3 (range 12.5-34.0) at d0 to 7.25 (range 1.0-13.5) at d14 (P < 0.0001). Immediately post-thaw, CBUs possess an ability to generate large BFU-like megakaryocytic colonies, whereas the colonies were not detectable in most CBUs in semisolid culture after a short suspension culture. Small CFU-Mks were observed throughout the cultures. It may be that the BFU-Mk colonies matured and acquired CFU-Mk behaviour. © 2014 International Society of Blood Transfusion.
Al Laham, Nahed; Rohde, Holger; Sander, Gunnar; Fischer, Andreas; Hussain, Muzaffar; Heilmann, Christine; Mack, Dietrich; Proctor, Richard; Peters, Georg; Becker, Karsten; von Eiff, Christof
2007-01-01
While coagulase-negative staphylococci (CoNS), with their ability to form a thick, multilayered biofilm on foreign bodies, have been identified as the major cause of implant-associated infections, no data are available about biofilm formation by staphylococcal small-colony variants (SCVs). In the past years, a number of device-associated infections due to staphylococcal SCVs were described, among them, several pacemaker infections due to SCVs of CoNS auxotrophic to hemin. To test the characteristics of SCVs of CoNS, in particular, to study the ability of SCVs to form a biofilm on foreign bodies, we generated a stable mutant in electron transport by interrupting one of the hemin biosynthetic genes, hemB, in Staphylococcus epidermidis. In fact, this mutant displayed a stable SCV phenotype with tiny colonies showing strong adhesion to the agar surface. When the incubation time was extended to 48 h or a higher inoculum concentration was used, the mutant produced biofilm amounts on polystyrene similar to those produced by the parent strain. When grown under planktonic conditions, the mutant formed markedly larger cell clusters than the parental strain which were completely disintegrated by the specific β-1,6-hexosaminidase dispersin B but were resistant to trypsin treatment. In a dot blot assay, the mutant expressed larger amounts of polysaccharide intercellular adhesin (PIA) than the parent strain. In conclusion, interrupting a hemin biosynthetic gene in S. epidermidis resulted in an SCV phenotype. Markedly larger cell clusters and the ability of the hemB mutant to form a biofilm are related to the augmented expression of PIA. PMID:17449620
Wilson, Ryan; Urraca, Nora; Skobowiat, Cezary; Hope, Kevin A.; Miravalle, Leticia; Chamberlin, Reed; Donaldson, Martin; Seagroves, Tiffany N.
2015-01-01
Dental pulp stem cells (DPSCs) provide an exciting new avenue to study neurogenetic disorders. DPSCs are neural crest-derived cells with the ability to differentiate into numerous tissues including neurons. The therapeutic potential of stem cell-derived lines exposed to culturing ex vivo before reintroduction into patients could be limited if the cultured cells acquired tumorigenic potential. We tested whether DPSCs that spontaneously immortalized in culture acquired features of transformed cells. We analyzed immortalized DPSCs for anchorage-independent growth, genomic instability, and ability to differentiate into neurons. Finally, we tested both spontaneously immortalized and human telomerase reverse transcriptase (hTERT)-immortalized DPSC lines for the ability to form tumors in immunocompromised animals. Although we observed increased colony-forming potential in soft agar for the spontaneously immortalized and hTERT-immortalized DPSC lines relative to low-passage DPSC, no tumors were detected from any of the DPSC lines tested. We noticed some genomic instability in hTERT-immortalized DPSCs but not in the spontaneously immortalized lines tested. We determined that immortalized DPSC lines generated in our laboratory, whether spontaneously or induced, have not acquired the potential to form tumors in mice. These data suggest cultured DPSC lines that can be differentiated into neurons may be safe for future in vivo therapy for neurobiological diseases. Significance This study demonstrated that immortalized dental pulp stem cells (DPSCs) do not form tumors in animals and that immortalized DPSCs can be differentiated into neurons in culture. These results lend support to the use of primary and immortalized DPSCs for future therapeutic approaches to treatment of neurobiological diseases. PMID:26032749
The Work of Dr. Ladislav Kosc on Dyscalculia.
ERIC Educational Resources Information Center
Sharma, Mahesh C., Ed.; Loveless, Eugene J., Ed.
1986-01-01
The work of Ladislav Kosc on dyscalculia is presented. His work on meanings, forms, terminology, diagnosis, correction principles, factors in mathematical ability, language dysfunctions, and publications are each included. (MNS)
Yeast Ivy1p Is a Putative I-BAR-domain Protein with pH-sensitive Filament Forming Ability in vitro.
Itoh, Yuzuru; Kida, Kazuki; Hanawa-Suetsugu, Kyoko; Suetsugu, Shiro
2016-01-01
Bin-Amphiphysin-Rvs161/167 (BAR) domains mold lipid bilayer membranes into tubules, by forming a spiral polymer on the membrane. Most BAR domains are thought to be involved in forming membrane invaginations through their concave membrane binding surfaces, whereas some members have convex membrane binding surfaces, and thereby mold membranes into protrusions. The BAR domains with a convex surface form a subtype called the inverse BAR (I-BAR) domain or IRSp53-MIM-homology domain (IMD). Although the mammalian I-BAR domains have been studied, those from other organisms remain elusive. Here, we found putative I-BAR domains in Fungi and animal-like unicellular organisms. The fungal protein containing the putative I-BAR-domain is known as Ivy1p in yeast, and is reportedly localized in the vacuole. The phylogenetic analysis of the I-BAR domains revealed that the fungal I-BAR-domain containing proteins comprise a distinct group from those containing IRSp53 or MIM. Importantly, Ivy1p formed a polymer with a diameter of approximately 20 nm in vitro, without a lipid membrane. The filaments were formed at neutral pH, but disassembled when pH was reverted to basic. Moreover, Ivy1p and the I-BAR domain expressed in mammalian HeLa cells was localized at a vacuole-like structure as filaments as revealed by super-resolved microscopy. These data indicate the pH-sensitive polymer forming ability and the functional conservation of Ivy1p in eukaryotic cells.
Molecular Design of Branched and Binary Molecules at Ordered Interfaces
DOE Office of Scientific and Technical Information (OSTI.GOV)
Genson, Kirsten Larson
2005-01-01
This study examined five different branched molecular architectures to discern the effect of design on the ability of molecules to form ordered structures at interfaces. Photochromic monodendrons formed kinked packing structures at the air-water interface due to the cross-sectional area mismatch created by varying number of alkyl tails and the hydrophilic polar head group. The lower generations formed orthorhombic unit cell with long range ordering despite the alkyl tails tilted to a large degree. Favorable interactions between liquid crystalline terminal groups and the underlying substrate were observed to compel a flexible carbosilane dendrimer core to form a compressed elliptical conformationmore » which packed stagger within lamellae domains with limited short range ordering. A twelve arm binary star polymer was observed to form two dimensional micelles at the air-water interface attributed to the higher polystyrene block composition. Linear rod-coil molecules formed a multitude of packing structures at the air-water interface due to the varying composition. Tree-like rod-coil molecules demonstrated the ability to form one-dimensional structures at the air-water interface and at the air-solvent interface caused by the preferential ordering of the rigid rod cores. The role of molecular architecture and composition was examined and the influence chemically competing fragments was shown to exert on the packing structure. The amphiphilic balance of the different molecular series exhibited control on the ordering behavior at the air-water interface and within bulk structures. The shell nature and tail type was determined to dictate the preferential ordering structure and molecular reorganization at interfaces with the core nature effect secondary.« less
Arunakul, Marut; Arunakul, Preeyaphan; Suesiritumrong, Chakhrist; Angthong, Chayanin; Chernchujit, Bancha
2015-06-01
Self-administered questionnaires have become an important aspect for clinical outcome assessment of foot and ankle-related problems. The Foot and Ankle Ability Measure (FAAM) subjective form is a region-specific questionnaire that is widely used and has sufficient validity and reliability from previous studies. Translate the original English version of FAAM into a Thai version and evaluate the validity and reliability of Thai FAAM in patients with foot and ankle-related problems. The FAAM subjective form was translated into Thai using forward-backward translation protocol. Afterward, reliability and validity were tested. Following responses from 60 consecutive patients on two questionnaires, the Thai FAAM subjective form and the short form (SF)-36, were used. The validity was tested by correlating the scores from both questionnaires. The reliability was adopted by measuring the test-retest reliability and internal consistency. Thai FAAM score including activity of daily life (ADL) and Sport subscale demonstrated the sufficient correlations with physical functioning (PF) and physical composite score (PCS) domains of the SF-36 (statistically significant with p < 0.001 level and ≥ 0.5 values). The result of reliability revealed highly intra-class correlation coefficient as 0.8 and 0.77, respectively from test-retest study. The internal consistency was strong (Cronbach alpha = 0.94 and 0.88, respectively). The Thai version of FAAM subjective form retained the characteristics of the original version and has proved a reliable evaluation instrument for patients with foot and ankle-related problems.
Bedore, Lisa M; Peña, Elizabeth D; Anaya, Jissel B; Nieto, Ricardo; Lugo-Neris, Mirza J; Baron, Alisa
2018-04-05
This study examines English performance on a set of 11 grammatical forms in Spanish-English bilingual, school-age children in order to understand how item difficulty of grammatical constructions helps correctly classify language impairment (LI) from expected variability in second language acquisition when taking into account linguistic experience and exposure. Three hundred seventy-eight children's scores on the Bilingual English-Spanish Assessment-Middle Extension (Peña, Bedore, Gutiérrez-Clellen, Iglesias, & Goldstein, 2008) morphosyntax cloze task were analyzed by bilingual experience groups (high Spanish experience, balanced English-Spanish experience, high English experience, ability (typically developing [TD] vs. LI), and grammatical form. Classification accuracy was calculated for the forms that best differentiated TD and LI groups. Children with LI scored lower than TD children across all bilingual experience groups. There were differences by grammatical form across bilingual experience and ability groups. Children from high English experience and balanced English-Spanish experience groups could be accurately classified on the basis of all the English grammatical forms tested except for prepositions. For bilinguals with high Spanish experience, it was possible to rule out LI on the basis of grammatical production but not rule in LI. It is possible to accurately identify LI in English language learners once they use English 40% of the time or more. However, for children with high Spanish experience, more information about development and patterns of impairment is needed to positively identify LI.
ERIC Educational Resources Information Center
Chen, Hanwei; Cui, Zhongmin; Zhu, Rongchun; Gao, Xiaohong
2010-01-01
The most critical feature of a common-item nonequivalent groups equating design is that the average score difference between the new and old groups can be accurately decomposed into a group ability difference and a form difficulty difference. Two widely used observed-score linear equating methods, the Tucker and the Levine observed-score methods,…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Burles, Kristin; Irwin, Chad R.; Burton, Robyn-Lee
Currently, little is known about the ankyrin/F-box protein B4. Here, we report that B4R-null viruses exhibited reduced plaque size in tissue culture, and decreased ability to spread, as assessed by multiple-step growth analysis. Electron microscopy indicated that B4R-null viruses still formed mature and extracellular virions; however, there was a slight decrease of virions released into the media following deletion of B4R. Deletion of B4R did not affect the ability of the virus to rearrange actin; however, VACV811, a large vaccinia virus deletion mutant missing 55 open reading frames, had decreased ability to produce actin tails. Using ectromelia virus, a naturalmore » mouse pathogen, we demonstrated that virus devoid of EVM154, the B4R homolog, showed decreased spread to organs and was attenuated during infection. This initial characterization suggests that B4 may play a role in virus spread, and that other unidentified mediators of actin tail formation may exist in vaccinia virus. - Highlights: • B4R-null viruses show reduced plaque size, and decreased ability to spread. • B4R-null viruses formed mature and extracellular virions; and rearranged actin. • Virus devoid of EVM154, the B4R homolog, was attenuated during infection. • Initial characterization suggests that B4 may play a role in virus spread. • Unidentified mediators of actin tail formation may exist in vaccinia virus.« less
Biofilm formation ability of Salmonella enterica serovar Typhimurium acrAB mutants.
Schlisselberg, Dov B; Kler, Edna; Kisluk, Guy; Shachar, Dina; Yaron, Sima
2015-10-01
Recent studies offer contradictory findings about the role of multidrug efflux pumps in bacterial biofilm development. Thus, the aim of this study was to investigate the involvement of the AcrAB efflux pump in biofilm formation by investigating the ability of AcrB and AcrAB null mutants of Salmonella enterica serovar Typhimurium to produce biofilms. Three models were used to compare the ability of S. Typhimurium wild-type and its mutants to form biofilms: formation of biofilm on polystyrene surfaces; production of biofilm (mat model) on the air/liquid interface; and expression of curli and cellulose on Congo red-supplemented agar plates. All three investigated genotypes formed biofilms with similar characteristics. However, upon exposure to chloramphenicol, formation of biofilms on solid surfaces as well as the production of curli were either reduced or were delayed more significantly in both mutants, whilst there was no visible effect on pellicle formation. It can be concluded that when no selective pressure is applied, S. Typhimurium is able to produce biofilms even when the AcrAB efflux pumps are inactivated, implying that the use of efflux pump inhibitors to prevent biofilm formation is not a general solution and that combined treatments might be more efficient. Other factors that affect the ability to produce biofilms depending on efflux pump activity are yet to be identified. Copyright © 2015 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.
[Influence of slime production and adhesion of Candida sp. on biofilm formation].
Ciok-Pater, Emilia; Smolak, Przemysław; Wróblewska, Joanna; Gospodarek, Eugenia
2011-01-01
The increase of fungal infections in recent years is connected with the progress in medicine. The vast usage of biomaterials is an inseparable element of contemporary medicine but it also leads to development of infections. Yeast-like fungi Candida albicans are still the main pathogen of candidiasis. The ability to slime production and adhesion to polystyrene of Candida sp. on different surfaces can cause to form biofilm on surfaces of biomaterials used in production of catheters, drains and prosthesis. The aim of the study was to evaluate the influence of slime production and adhesion to polystyrene, of Candida sp. on biofilm formation on different biomaterials. 50 strains of Candida sp. were examined. They isolated from ill to Clinics of Anesthesiology and Intensive Therapy University Hospital No 1 of dr. A. Jurasza in Bydgoszcz. The ability to slime production was evaluated by Christensen method in modification Davenport and Branchini methods. The adhesion to polystyrene was evaluated by Richards et el method. The ability to produce biofilm biomaterials by the studied fungi was measured after 72 hours of incubation at 37 degrees C on different biomaterials. Yeast-like fungi Candida sp. fabricating slime and adhesion forming frequently biofilm on surface researched of biomaterials. Influence of chosen biological specificity ascertain on the ability to produce biofilm on surfaces of siliconized latex and polyvinylchloride.
Using Form and Function Analogy Object Boxes to Teach Human Body Systems
ERIC Educational Resources Information Center
Rule, Audrey C.; Furletti, Charles
2004-01-01
This study compares the use of form and function analogy object boxes to more traditional lecture and worksheet instruction during a 10th-grade unit on human body systems. The study was conducted with two classes (N = 32) of mixed ability students at a high-needs rural high school in central New York State. The study used a pretest/posttest…
Clustering of Rac1: Selective Lipid Sorting Drives Signaling.
Maxwell, Kelsey N; Zhou, Yong; Hancock, John F
2018-02-01
The ability of lipid-anchored small GTPases to form nanometer-scale lipid domains on the cell plasma membrane (PM) is precipitating exciting new insights into membrane-anchored protein regulation. A recent article by Remorino et al. demonstrates that Rac1, similar to Ras, forms nanoclusters on the PM. The implications of these findings are discussed herein. Copyright © 2017. Published by Elsevier Ltd.
USDA-ARS?s Scientific Manuscript database
Biofilms formed by human enteric pathogens on plants are a great concern to the produce industry. Salmonella enterica has the ability to form biofilms and large aggregates on leaf surfaces, including on cilantro leaves. Aggregates that remained attached after rigorous washing of cilantro leaves and ...
ERIC Educational Resources Information Center
Andrews, Benjamin James
2011-01-01
The equity properties can be used to assess the quality of an equating. The degree to which expected scores conditional on ability are similar between test forms is referred to as first-order equity. Second-order equity is the degree to which conditional standard errors of measurement are similar between test forms after equating. The purpose of…
ERIC Educational Resources Information Center
DUENK, LESTER G.
THE PRIMARY OBJECTIVE OF THIS STUDY WAS TO ESTABLISH THE CONCURRENT VALIDITY OF THE MINNESOTA TESTS OF CREATIVE THINKING, ABBREVIATED FORM VII, (MTCT VII) BY DETERMINING THE RELATIONSHIP BETWEEN ITS SCORES AND CREATIVE ABILITY AS MEASURED BY ACCUMULATED TEACHER RATINGS OF INDUSTRIAL ARTS PROJECTS AND INVESTIGATOR-DEVELOPED TESTS OF CREATIVITY. THE…
Dissociations between Imagery and Language Processing.
1984-08-20
to form the image on the basis of information stored in memory . We wanted to eliminate such processing in order to assess image maintenance ability...of imagery described in Kosslyn (1980), three processing modules are used in generating an image from information stored in long-term memory . The...PICTURE processing module simply activates the stored information, forming an image in short-term memory . However, this processing module only activates
ERIC Educational Resources Information Center
So, Pety; Greaves-Lord, Kirstin; van der Ende, Jan; Verhulst, Frank C.; Rescorla, Leslie; de Nijs, Pieter F. A.
2013-01-01
This study evaluated the ability of the Child Behavior Checklist and the Teacher's Report Form to identify children with autism spectrum disorders (ASD), using a sample of children with ASD (n = 458), referred children without ASD (n = 1109) and children from the general population (n = 999). A ten items ASD scale was constructed using half of the…
ERIC Educational Resources Information Center
Enciso Bernal, Ana Maria
2014-01-01
This study investigated the effects of concurrent audio and equivalent onscreen text on the ability of learners of English as a foreign language (EFL) to form associations between textual and aural forms of target vocabulary words. The study also looked at the effects of learner control over an audio sequence on the association of textual and…
Greene, C; Wu, J; Rickard, A H; Xi, C
2016-10-01
The human opportunistic pathogen, Acinetobacter baumannii, has the propensity to form biofilms and frequently cause medical device-related infections in hospitals. However, the physio-chemical properties of medical surfaces, in addition to bacterial surface properties, will affect colonization and biofilm development. The objective of this study was to compare the ability of A. baumannii to form biofilms on six different materials common to the hospital environment: glass, porcelain, stainless steel, rubber, polycarbonate plastic and polypropylene plastic. Biofilms were developed on material coupons in a CDC biofilm reactor. Biofilms were visualized and quantified using fluorescent staining and imaged using confocal laser scanning microscopy (CLSM) and by direct viable cell counts. Image analysis of CLSM stacks indicated that the mean biomass values for biofilms grown on glass, rubber, porcelain, polypropylene, stainless steel and polycarbonate were 0·04, 0·26, 0·62, 1·00, 2·08 and 2·70 μm(3) /μm(2) respectively. Polycarbonate developed statistically more biofilm mass than glass, rubber, porcelain and polypropylene. Viable cell counts data were in agreement with the CLSM-derived data. In conclusion, polycarbonate was the most accommodating surface for A. baumannii ATCC 17978 to form biofilms while glass was least favourable. Alternatives to polycarbonate for use in medical and dental devices may need to be considered. In the hospital environment, Acinetobacter baumannii is one of the most persistent and difficult to control opportunistic pathogens. The persistence of A. baumannii is due, in part, to its ability to colonize surfaces and form biofilms. This study demonstrates that A. baumannii can form biofilms on a variety of different surfaces and develops substantial biofilms on polycarbonate - a thermoplastic material that is often used in the construction of medical devices. The findings highlight the need to further study the in vitro compatibility of medical materials that could be colonized by A. baumannii and allow it to persist in hospital settings. © 2016 The Society for Applied Microbiology.
[Impact of work place stresses on work ability index in patients with depressive disorders].
Lazarević, Sanja Brekalo; Pranjić, Nurka; Selmanović, Senada; Grbović, Mensur
2011-01-01
Depression seriously affects one's ability to perform work tasks and function at work. We studied the impact of both the individual and work factors on work ability index in patients suffering from depression. The prospective study, which was conducted by using questionnaires, included 210 patients with depression, who had been on sick leave from 60 to 360 days. The individual factors were evaluated by the standardized abridged form of Occupational Stress Questionnaire, while the work place factors in relation to work ability were evaluated by the work ability index. Poor work ability was observed in 151 (71%) of subjects suffering from depression. All workplace stresses, lack of support by colleagues and supervisors, ergonomically not adjusted work and huge work load are statistically associated with poor work ability index (P=0.001). More than 95% of variables of the evaluated work ability index are the result of varying in the group of stresses at work place (R2=0.95). Perception of bad health condition (Rsq=0.412, P=0.001), low level of life satisfaction (Rsq=0.309, P=0.001), low level of motivation and work knowledge (Rsq=0.309, P=0.001) are predictors for poor work ability. The work ability cannot be related with age and sex. The key activities for maintaining the work ability at the times when epidemic of depression emerges, as it is nowadays, are timely carrying out the psycho-treatments, mental and professional rehabilitation, occupational therapy and adapted work place.
... and ability to form and sustain friendships. Understanding Bullying Behavior Kids bully for many reasons. Some bully ... children they perceive as weak. Helping Kids Stop Bullying Let your child know that bullying is unacceptable ...
... forms of MD grow worse as the person's muscles get weaker. Most people with MD eventually lose the ability to walk. There is no cure for muscular dystrophy. Treatments can help with the symptoms and prevent complications. ...
Teaching Reform of Civil Engineering Materials Course Based on Project-Driven Pedagogy
NASA Astrophysics Data System (ADS)
Yidong, Xu; Wei, Chen; WeiguoJian, You; Jiansheng, Shen
2018-05-01
In view of the scattered experimental projects in practical courses of civil engineering materials, the poor practical ability of students and the disconnection between practical teaching and theoretical teaching, this paper proposes a practical teaching procedure. Firstly, the single experiment should be offered which emphasizes on improving the students’ basic experimental operating ability. Secondly, the compressive experiment is offered and the overall quality of students can be examined in the form of project team. In order to investigate the effect of teaching reform, the comparative analysis of the students of three grades (2014, 2015 and 2016) majored in civil engineering was conducted. The result shows that the students’ ability of experimental operation is obviously improved by using the project driven method-based teaching reform. Besides, the students’ ability to analyse and solve problems has also been improved.
NASA Astrophysics Data System (ADS)
Nasution, M. L.; Yerizon, Y.; Gusmiyanti, R.
2018-04-01
One of the purpose mathematic learning is to develop problem solving abilities. Problem solving is obtained through experience in questioning non-routine. Improving students’ mathematical problem-solving abilities required an appropriate strategy in learning activities one of them is models problem based learning (PBL). Thus, the purpose of this research is to determine whether the problem solving abilities of mathematical students’ who learn to use PBL better than on the ability of students’ mathematical problem solving by applying conventional learning. This research included quasi experiment with static group design and population is students class XI MIA SMAN 1 Lubuk Alung. Class experiment in the class XI MIA 5 and class control in the class XI MIA 6. The instrument of final test students’ mathematical problem solving used essay form. The result of data final test in analyzed with t-test. The result is students’ mathematical problem solving abilities with PBL better then on the ability of students’ mathematical problem solving by applying conventional learning. It’s seen from the high percentage achieved by the group of students who learn to use PBL for each indicator of students’ mathematical problem solving.
Predictors of chewing ability among community-residing older adults in Korea.
Park, Kyongok; Hong, Gwi-Ryung Son
2017-01-01
Decreased chewing ability in older adults can lead to poor nutritional and physical conditions, and eventually death. The present study examined the relationships between chewing ability and related characteristics (e.g. health promotion habits, health status and functional status), and identified predictors of chewing ability in community-residing older adults. Among the total of 11 542 participants in the 2011 National Survey on Older Adults in Korea, data from 10 543 participants were used for analysis. Chewing ability was evaluated using a self-report of chewing ability. Exercise ability was assessed by objective exercise ability and perceived exercise ability in both the upper and lower extremities. Depression and cognitive functions were measured using the Geriatric Depression Scale-Short Form and the Mini-Mental State Examination, respectively. A total of 56.9% of participants had poor chewing abilities. After adjusting for age and sex, logistic regression analysis showed that depression (OR 1.76, 95% CI 1.60-1.92), cognitive impairment (OR 1.28, 95% CI 1.17-1.40), objective exercise ability (OR 1.24, 95% CI 1.11-1.41), regular exercise habits (OR 1.23, 95% CI 1.13-1.34), medical check-up history (OR 1.17, 95% CI 1.05-1.32), number of chronic diseases (OR 1.12, 95% CI 1.09-1.15) and perceived exercise ability in the lower extremities (OR 1.08, 95% CI 1.05-1.10) were significant predictors of chewing ability. Chewing ability in older adults should be improved in consideration of mental and general health condition. Geriatr Gerontol Int 2017; 17: 78-84. © 2015 Japan Geriatrics Society.
Fundamental Aspects of the Financing of Information Centres
ERIC Educational Resources Information Center
Schwuchow, Werner
1973-01-01
Five aspects of financing information centers are discussed: source of funds (public or private), profit-making ability, tax revenues versus fee sources, fee calculation, and forms of tariff structures. (4 references) (SJ)
Design and Characterisation of Metallic Glassy Alloys of High Neutron Shielding Capability
NASA Astrophysics Data System (ADS)
Khong, J. C.; Daisenberger, D.; Burca, G.; Kockelmann, W.; Tremsin, A. S.; Mi, J.
2016-11-01
This paper reports the design, making and characterisation of a series of Fe-based bulk metallic glass alloys with the aim of achieving the combined properties of high neutron absorption capability and sufficient glass forming ability. Synchrotron X-ray diffraction and pair distribution function methods were used to characterise the crystalline or amorphous states of the samples. Neutron transmission and macroscopic attenuation coefficients of the designed alloys were measured using energy resolved neutron imaging method and the very recently developed microchannel plate detector. The study found that the newly designed alloy (Fe48Cr15Mo14C15B6Gd2 with a glass forming ability of Ø5.8 mm) has the highest neutron absorption capability among all Fe-based bulk metallic glasses so far reported. It is a promising material for neutron shielding applications.
NASA Technical Reports Server (NTRS)
Ethridge, E. C.; Kaukler, W. F.
1993-01-01
A number of promising glass forming compositions of high Tc superconducting Ba-Sr-Ca-Cu-O (BSCCO) materials were evaluated for their glass-ceramic crystallization ability. The BSCCO ceramics belonging to the class of superconductors in the Ba-Sr-Ca-Cu-O system were the focus of this study. By first forming the superconducting material as a glass, subsequent devitrification into the crystalline (glass-ceramic) superconductor can be performed by thermal processing of the glass preform body. Glass formability and phase formation were determined by a variety of methods in another related study. This study focused on the nucleation and crystallization of the materials. Thermal analysis during rapid cooling aids in the evaluation of nucleation and crystallization behavior. Melt viscosity is used to predict glass formation ability.
Design and Characterisation of Metallic Glassy Alloys of High Neutron Shielding Capability.
Khong, J C; Daisenberger, D; Burca, G; Kockelmann, W; Tremsin, A S; Mi, J
2016-11-16
This paper reports the design, making and characterisation of a series of Fe-based bulk metallic glass alloys with the aim of achieving the combined properties of high neutron absorption capability and sufficient glass forming ability. Synchrotron X-ray diffraction and pair distribution function methods were used to characterise the crystalline or amorphous states of the samples. Neutron transmission and macroscopic attenuation coefficients of the designed alloys were measured using energy resolved neutron imaging method and the very recently developed microchannel plate detector. The study found that the newly designed alloy (Fe 48 Cr 15 Mo 14 C 15 B 6 Gd 2 with a glass forming ability of Ø5.8 mm) has the highest neutron absorption capability among all Fe-based bulk metallic glasses so far reported. It is a promising material for neutron shielding applications.
Micro-elastometry on whole blood clots using actuated surface-attached posts (ASAPs).
Judith, Robert M; Fisher, Jay K; Spero, Richard Chasen; Fiser, Briana L; Turner, Adam; Oberhardt, Bruce; Taylor, R M; Falvo, Michael R; Superfine, Richard
2015-03-07
We present a novel technology for microfluidic elastometry and demonstrate its ability to measure stiffness of blood clots as they form. A disposable micro-capillary strip draws small volumes (20 μL) of whole blood into a chamber containing a surface-mounted micropost array. The posts are magnetically actuated, thereby applying a shear stress to the blood clot. The posts' response to magnetic field changes as the blood clot forms; this response is measured by optical transmission. We show that a quasi-static model correctly predicts the torque applied to the microposts. We experimentally validate the ability of the system to measure clot stiffness by correlating our system with a commercial thromboelastograph. We conclude that actuated surface-attached post (ASAP) technology addresses a clinical need for point-of-care and small-volume elastic haemostatic assays.
Two distinct forms of functional lateralization in the human brain
Gotts, Stephen J.; Jo, Hang Joon; Wallace, Gregory L.; Saad, Ziad S.; Cox, Robert W.; Martin, Alex
2013-01-01
The hemispheric lateralization of certain faculties in the human brain has long been held to be beneficial for functioning. However, quantitative relationships between the degree of lateralization in particular brain regions and the level of functioning have yet to be established. Here we demonstrate that two distinct forms of functional lateralization are present in the left vs. the right cerebral hemisphere, with the left hemisphere showing a preference to interact more exclusively with itself, particularly for cortical regions involved in language and fine motor coordination. In contrast, right-hemisphere cortical regions involved in visuospatial and attentional processing interact in a more integrative fashion with both hemispheres. The degree of lateralization present in these distinct systems selectively predicted behavioral measures of verbal and visuospatial ability, providing direct evidence that lateralization is associated with enhanced cognitive ability. PMID:23959883
Crawford, H J; Brown, A M; Moon, C E
1993-11-01
Relations between sustained attentional and disattentional abilities and hypnotic susceptibility (Harvard Group Scale of Hypnotic Susceptibility: Form A; Stanford Hypnotic Susceptibility Scale: Form C) were examined in 38 low (0-3) and 39 highly (10-12) hypnotizable college students. Highs showed greater sustained attention on Necker cube and autokinetic movement tasks and self-reported greater absorption (Tellegen Absorption Scale) and extremely focused attentional (Differential Attentional Processes Inventory) styles. Hypnotizability was unrelated to dichotic selective attention (A. Karlin, 1979) and random number generation (C. Graham & F. J. Evans, 1977) tasks. Discriminant analysis correctly classified 74% of the lows and 69% of the highs. Results support H. J. Crawford and J. H. Gruzelier's (1992) neuropsychophysiological model of hypnosis that proposes that highly hypnotizable persons have a more efficient far frontolimbic sustained attentional and disattentional system.
NASA Astrophysics Data System (ADS)
Tuchina, Elena S.; Permyakova, Natalia F.; Tuchin, Valery V.
2007-05-01
Photodynamic therapy (PDT) now is widespread for treatment of the various skin infections caused by Propionibacterium acnes or Staphylococcii spp. We used PDT for influence on opportunistic microflora of human skin presented by Staphylococcus hominis, S. warnery, S. epidermidis S. aureus 209 P, S. aureus 69. Species S. epidermidis, S. aureus 209 P, S. hominis to some extent reduced colonies forming ability under action of dual wavelength LED-light (442 nm and 597 nm). For species S. warnery, S. aureus 69 the increase in CFU number under action of light relative to control was characteristic. Our experiments have shown, that phototherapy can be used for treatment of diseases associated with S. aureus 209 P. The doze 8 J/cm2 caused reduction in CFU of this species on 40% relative to control.
Study on the ability of a new barrier to reduce airborne mite allergens.
Rigamonti, I E; Di Berardino, L; Lozzia, G C
1996-03-01
Environmental control, especially means for blocking the release into the air of mite allergens embedded in padded furniture (mattress, pillows), represents the first important step in the treatment of IgE-mediated allergic diseases. New to the market is a home hygiene spray that creates a protective barrier on padded furniture and is thereby able to contain the dispersion into the air of allergic particles. We tested the effectiveness of the spray in vitro. Since mites, especially D. Pteronyssinus, are considered the foremost allergens, we verified the ability of the invisible barrier to impede the diffusion of the allergen and the mobile forms of these mites (Der p 1, Der 2). The product under exam created a barrier that totally blocked the passage of mobile forms and almost totally prevented the passage of allergens (> 99%).
Lenz, Michael; Kard, Brad; Creffield, James W; Evans, Theodore A; Brown, Kenneth S; Freytag, Edward D; Zhong, Jun-Hong; Lee, Chow-Yang; Yeoh, Boon-Hoi; Yoshimura, Tsuyoshi; Tsunoda, Kunio; Vongkaluang, Charunee; Sornnuwat, Yupaporn; Roland, Ted A; de Santi, Marie Pommier
2013-06-01
A comparative field study was conducted to evaluate the ability of subterranean termites to damage a set of four different plastic materials (cable sheathings) exposed below- and above-ground. Eight pest species from six countries were included, viz., Coptotermes formosanus (Shiraki) in China, Japan, and the United States; Coptotermes gestroi (Wasmann) in Thailand and Malaysia; Coptotermes curvignathus (Holmgren) and Coptotermes kalshoveni (Kemner) in Malaysia; Coptotermes acinaciformis (Froggatt) with two forms of the species complex and Mastotermes darwiniensis (Froggatt) in Australia; and Reticulitermes flavipes (Kollar) in the United States. Termite species were separated into four tiers relative to decreasing ability to damage plastics. The first tier, most damaging, included C. acinaciformis, mound-building form, and M. darwiniensis, both from tropical Australia. The second tier included C. acinaciformis, tree-nesting form, from temperate Australia and C. kalshoveni from Southeast Asia. The third tier included C. curcignathus and C. gestroi from Southeast Asia and C. formosanus from China, Japan, and the United States, whereas the fourth tier included only R. flavipes, which caused no damage. A consequence of these results is that plastics considered resistant to termite damage in some locations will not be so in others because of differences in the termite fauna, for example, resistant plastics from the United States and Japan will require further testing in Southeast Asia and Australia. However, plastics considered resistant in Australia will be resistant in all other locations.
Lamas, A; Fernandez-No, I C; Miranda, J M; Vázquez, B; Cepeda, A; Franco, C M
2016-07-01
Salmonella serovars are responsible for foodborne diseases around the world. The ability to form biofilms allows microorganisms to survive in the environment. In this study, 73 Salmonella strains, belonging to four different subspecies, were isolated from poultry houses and foodstuffs and tested. Biofilm formation was measured at four different temperatures and two nutrient concentrations. Morphotypes and cellulose production were evaluated at three different temperatures. The presence of several genes related to biofilm production was also examined. All strains and subspecies of Salmonella had the ability to form biofilms, and 46.57% of strains produced biofilms under all conditions tested. Biofilm formation was strain dependent and varied according to the conditions. This is the first study to analyze biofilm formation in a wide number of Salmonella enterica subsp. arizonae strains, and no direct relationship between the high prevalence of Salmonella enterica subsp. arizonae strains and their ability to form biofilm was established. Morphotypes and cellulose production varied as the temperature changed, with 20°C being the optimum temperature for expression of the red, dry, and rough morphotype and cellulose. Salmonella enterica subsp. arizonae, whose morphotype is poorly studied, only showed a smooth and white morphotype and lacked the csgD and gcpA genes that are implicated in biofilm production. Thus, Salmonella biofilm formation under different environmental conditions is a public health problem because it can survive and advance through the food chain to reach the consumer.
NASA Technical Reports Server (NTRS)
Kaiser, Mary Kister; Remington, Roger
1988-01-01
Spatial cognition is the ability to reason about geometric relationships in the real (or a metaphorical) world based on one or more internal representations of those relationships. The study of spatial cognition is concerned with the representation of spatial knowledge, and our ability to manipulate these representations to solve spatial problems. Spatial cognition is utilized most critically when direct perceptual cues are absent or impoverished. Examples are provided of how human spatial cognitive abilities impact on three areas of space station operator performance: orientation, path planning, and data base management. A videotape provides demonstrations of relevant phenomena (e.g., the importance of orientation for recognition of complex, configural forms). The presentation is represented by abstract and overhead visuals only.
Hu, Jian; Feng, Xiangping; Yang, Zhongguo; Chen, Zhuoxin; Zhang, Wenqing
2014-07-01
A continuous cell line, SYSU-OfHe-C, from larval hemocytes of corn borer, Ostrinia furnacalis was established. With increasing passages, the cells grew increasingly faster, and approximately 45% of the cells were in division at passage 55. The culture was mainly composed of two types of cells, granulocytes and plasmatocytes, which showed different division and proliferation behaviors, but possessed similar phagocytic ability. Its spreading ability was significantly weaker than that of hemocytes from naïve larva; however, it could be promoted by larval plasma. Furthermore, its encapsulation ability was also promoted by larval plasma to form multilayer capsules on Sephadex A-25 beads. Finally, the expression of several immune-related genes was verified after provocation by microbes or Sephadex beads. These results indicated that the cell line possessed immune ability depending on the presence of plasma of naïve larvae and are beneficial to studies of insect cellular systems. Copyright © 2014 Elsevier Ltd. All rights reserved.
Glass formability of high T(sub c) Bi-Sr-Ca-Cu-O superconductors
NASA Technical Reports Server (NTRS)
Kaukler, William F.
1992-01-01
A number of compositions of ceramic oxide high T(sub c) superconductors were evaluated for their glass formation ability by means of rapid thermal analysis during quenching, optical and electron microscopy of the quenched samples, and with subsequent DSC measurements. Correlations between experimental measurements and the methodical composition changes identified the formulations of superconductors that can easily form glass. The superconducting material was first formed as a glass, then with subsequent devitrification it was formed into bulk crystalline superconductor by a series of processing methods.
NASA Technical Reports Server (NTRS)
Andrews, J. B.; Curreri, P. A.; Sandlin, A. C.
1988-01-01
Results on the nondirectional solidification of several hypermonotectic Cu-Pb-Al alloys were obtained aboard NASA's KC-135 zero-gravity aircraft in order to determine the influence of interfacial energies and gravity levels on dispersion-forming tendencies. The Al content was systematially varied in the alloys. The dispersion-forming ability is correlated with gravity level during solidification, the interfacial energy between the immiscible phases, and the tendency for the minority immiscible phase to wet the walls of the crucible.
Liu, Chen-Chi; Lin, Shih-Pei; Hsu, Han-Shui; Yang, Shung-Haur; Lin, Chiu-Hua; Yang, Muh-Hwa; Hung, Mien-Chie; Hung, Shih-Chieh
2016-01-01
Targeting tumour-initiating cells (TICs) would lead to new therapies to cure cancer. We previously demonstrated that TICs have the capacity to survive under suspension conditions, while other cells undergo anoikis. Here we show that TICs exhibit increased phosphorylation levels of S727STAT3 because of PP2A inactivation. Collagen 17 gene expression is upregulated in a STAT3-dependent manner, which also stabilizes laminin 5 and engages cells to form hemidesmosome-like junctions in response. Blocking the PP2A-S727STAT3-collagen 17 pathway inhibits the suspension survival of TICs and their ability to form tumours in mice, while activation of the same pathway increases the suspension survival and tumour-initiation capacities of bulk cancer cells. The S727STAT3 phosphorylation levels correlate with collagen 17 expression in colon tumour samples, and correlate inversely with survival. Finally, this signalling axis enhances the ability of TIC to form tumours in mouse models of malignant lung cancer pleural effusion and spontaneous colon cancer metastasis. PMID:27306323
Liu, Chen-Chi; Lin, Shih-Pei; Hsu, Han-Shui; Yang, Shung-Haur; Lin, Chiu-Hua; Yang, Muh-Hwa; Hung, Mien-Chie; Hung, Shih-Chieh
2016-06-16
Targeting tumour-initiating cells (TICs) would lead to new therapies to cure cancer. We previously demonstrated that TICs have the capacity to survive under suspension conditions, while other cells undergo anoikis. Here we show that TICs exhibit increased phosphorylation levels of S727STAT3 because of PP2A inactivation. Collagen 17 gene expression is upregulated in a STAT3-dependent manner, which also stabilizes laminin 5 and engages cells to form hemidesmosome-like junctions in response. Blocking the PP2A-S727STAT3-collagen 17 pathway inhibits the suspension survival of TICs and their ability to form tumours in mice, while activation of the same pathway increases the suspension survival and tumour-initiation capacities of bulk cancer cells. The S727STAT3 phosphorylation levels correlate with collagen 17 expression in colon tumour samples, and correlate inversely with survival. Finally, this signalling axis enhances the ability of TIC to form tumours in mouse models of malignant lung cancer pleural effusion and spontaneous colon cancer metastasis.
Zieg, J; Maples, V F; Kushner, S R
1978-01-01
Escherichia coli strains containing mutations in lexA, rep, uvrA, uvrD, uvrE, lig, polA, dam, or xthA were constructed and tested for conjugation and transduction proficiencies and ability to form Lac+ recombinants in an assay system utilizing a nontandem duplication of two partially deleted lactose operons (lacMS286phi80dIIlacBK1). lexA and rep mutants were as deficient (20% of wild type) as recB and recC strains in their ability to produce Lac+ progeny. All the other strains exhibited increased frequencies of Lac+ recombinant formation, compared with wild type, ranging from 2- to 13-fold. Some strains showed markedly increased conjugation proficiency (dam uvrD) compared to wild type, while others appeared deficient (polA107). Some differences in transduction proficiency were also observed. Analysis of the Lac+ recombinants formed by the various mutants indicated that they were identical to the recombinants formed by a wild-type strain. The results indicate that genetic recombination in E. coli is a highly regulated process involving multiple gene products. PMID:350859
NASA Astrophysics Data System (ADS)
Tang, Hui; Yu, Dezhen; Luo, Yan; Wang, Fuping
2013-01-01
Magnesium and its alloys are potential biodegradable implant materials due to their attractive biological properties. But the use of magnesium is still hampered by its poor corrosion resistance in physiological fluids. In this work, hydroxyapatite microflowers coating is fabricated by micro-arc oxidation and a solution treatment on AZ31 magnesium alloy. The microstructure and composition are analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). The potentiodynamic polarization and electrochemical impedance spectroscopy are studied in simulated body fluid (SBF) solution, and the apatite-forming ability is studied also. The results show that the corrosion resistance of the magnesium alloy has been enhanced by MAO coating. And the solution treatment can improve the corrosion resistance of the MAO sample, by forming a barrier layer on the surface of the MAO coating, and by penetrating into the outer layer of the MAO film, sealing the micropores and micro-cracks existed in the MAO coating. In addition, the MAO-ST coating also exhibits a high ability to form apatite.
Study of polymorphism using patterned self-assembled monolayers approach on metal substrates
NASA Astrophysics Data System (ADS)
Quiñones, Rosalynn; Brown, Ryanne T.; Searls, Noah; Richards-Waugh, Lauren
2018-01-01
Polymorphism is a molecule's ability to possess altered physical crystalline structures and has become an active interest in pharmaceuticals due to its ability to influence a drug's physical and chemical properties. Crystal stability and solubility are crucial in determining a drug's pharmacokinetics and pharmacodynamics. Changes in these properties due to polymorphisms have contributed to recalls and modifications in industrial production. For this study, the effects of surface interactions with pharmaceuticals were examined through surface modification methodology using organic phosphonic and sulfonic acid self-assembled monolayers (SAMs) developed on a nickel or zinc oxide metal substrate. Drugs analyzed included carbamazepine, cimetidine, tolfenamic acid, and flufenamic acid. All drugs were thermodynamically applied to the reformed surface to aid in recrystallization. It was hypothesized and confirmed that intermolecular bonds, especially hydrogen bonds between the SAMs and pharmaceutical drugs, were the force that assisted in polymorph development. The study was successful in revealing multiple forms for each drug, including their commercial form and at least one additional form using micro FT-IR, Raman spectroscopy, and PXRD. Visual comparisons of crystal polymorphisms were performed with IR microscopy.
Kapidzić-Basić, Nedima; Dzananović, Dzevad; Kapidzić-Duraković, Suada; Kikanović, Sahza; Mulić-Bacić, Suada; Hotić-Hadziefendić, Asja
2011-01-01
In the most severe form of structural changes on knee caused by osteoarthritis non-surgical treatment provide minimal results and a question of its purpose is being raised. Aim of the study was to examine the possibilities of physical treatment of patients with the most severe degree of structural changes caused by knee osteoarthritis. Examination was conducted on 60 patients that were on physical treatment because of the knee OA. Structural changes are evaluated by Kellgren-Lawrence scale, functional ability by Lequesne index, and pain by Visual analog scale. Physical treatment lasted for 4 weeks. After the physical treatment there was a significant improvement of functional ability (p = 1.78E-07), but the size of improvement was reduced by the level of structural changes. It was significantly lower in IV class in relation to III and II class (p < 0.05). Physical treatment has lower affect by patients with the most severe form of structural changes caused by knee osteoarthritis, but it still can help patients to ease the appearance of complete dependence on other people's help.
Vernier But Not Grating Acuity Contributes to an Early Stage of Visual Word Processing.
Tan, Yufei; Tong, Xiuhong; Chen, Wei; Weng, Xuchu; He, Sheng; Zhao, Jing
2018-03-28
The process of reading words depends heavily on efficient visual skills, including analyzing and decomposing basic visual features. Surprisingly, previous reading-related studies have almost exclusively focused on gross aspects of visual skills, while only very few have investigated the role of finer skills. The present study filled this gap and examined the relations of two finer visual skills measured by grating acuity (the ability to resolve periodic luminance variations across space) and Vernier acuity (the ability to detect/discriminate relative locations of features) to Chinese character-processing as measured by character form-matching and lexical decision tasks in skilled adult readers. The results showed that Vernier acuity was significantly correlated with performance in character form-matching but not visual symbol form-matching, while no correlation was found between grating acuity and character processing. Interestingly, we found no correlation of the two visual skills with lexical decision performance. These findings provide for the first time empirical evidence that the finer visual skills, particularly as reflected in Vernier acuity, may directly contribute to an early stage of hierarchical word processing.
Viscous flow of the Pd43Ni10Cu27P20 bulk metallic glass-forming liquid
NASA Astrophysics Data System (ADS)
Fan, G. J.; Fecht, H.-J.; Lavernia, E. J.
2004-01-01
The equilibrium viscosity of the Pd43Ni10Cu27P20 bulk metallic glass-forming liquid was measured over a wide temperature range from the equilibrium supercooled liquid state to the glass transition region using parallel-plate rheometry and three-point beam bending. Based on the measured viscosity data, the fragility of this liquid was quantitatively determined. The Pd43Ni10Cu27P20 alloy, despite exhibiting the best glass-forming ability reported thus far, is relatively fragile compared with other bulk glass-forming liquids, such as Vit 1 and Vit 4.
III-V Compounds and Alloys: An Update.
Woodall, J M
1980-05-23
The III-V compounds and alloys have been studied for three decades. Until recently, these materials have been commercialized for only a few specialized optoelectronic devices and microwave devices. Advances in thin-film epitaxy techniques, such as liquid phase epitaxy and chemical vapor deposition, are now providing the ability to form good quality lattice-matched heterojunctions with III-V materials. New optoelectronic devices, such as room-temperature continuous-wave injection lasers, have already resulted. This newfound ability may also affect the field of highspeed integrated circuits.
van den Berg, T I J; Alavinia, S M; Bredt, F J; Lindeboom, D; Elders, L A M; Burdorf, A
2008-08-01
The purpose of this article is to explore the associations of psychosocial factors at work, life style, and stressful life events on health and work ability among white-collar workers. A cross-sectional survey was conducted among workers in commercial services (n = 1141). The main outcome variables were work ability, measured by the work ability index (WAI), and mental and physical health, measured by the Short-Form Health Survey (SF-12). Individual characteristics, psychosocial factors at work, stressful life events, and lifestyle factors were determined by a questionnaire. Maximum oxygen uptake, weight, height, and biceps strength were measured during a physical examination. Work ability of white-collar workers in commercial services industry was strongly associated with psychosocial factors at work such as teamwork, stress handling, and self-development and, to a lesser extent, with stressful life events, lack of physical activity, and obesity. Determinants of mental health were very similar to those of work ability, whereas physical health was influenced primarily by life style factors. With respect to work ability, the influence of unhealthy life style seems more important for older workers, than for their younger colleagues. Among white-collar workers mental and physical health were of equal importance to work ability, but only mental health and work ability shared the same determinants. The strong associations between psychosocial factors at work and mental health and work ability suggest that in this study population health promotion should address working conditions rather than individual life style factors.
ERIC Educational Resources Information Center
Gallego, Muriel
2016-01-01
The present study investigates whether the implementation of a dictogloss task within a proactive Focus on Form approach (e.g., Long 1991; Long and Robinson 1998) has significant effects on the acquisition of Spanish present subjunctive. A total of sixty-six learners in a fifth-semester Spanish course participated in the study and were assigned to…
ERIC Educational Resources Information Center
Clayman, Deborah P. Goldweber
The ability of 100 second-grade boys and girls to self-correct oral reading errors was studied in relationship to visual-form perception, phonic skills, response speed, and reading level. Each child was tested individually with the Bender-Error Test, the Gray Oral Paragraphs, and the Roswell-Chall Diagnostic Reading Test and placed into a group of…
Basic-Level Category Discriminations by 7- and 9-Month-Olds in an Object Examination Task.
ERIC Educational Resources Information Center
Mareschal, Denis; Powell, Daisy; Volein, Agnes
2003-01-01
Examined 7- and 9-month-olds' ability to categorize cats and dogs as separate from one another. Found that both groups formed a cat category that included novel cats but excluded a dog and an eagle, and formed a dog category that included novel dogs and a novel cat but excluded an eagle. Results mirrored those of 3- to 4-month-olds with visual…
ERIC Educational Resources Information Center
Lindstrom, David R.; Shipman, Virginia C.
The Seguin Form Board Test is used to assess visual discrimination and matching and eye-hand coordination. Previous analysis has shown the vactor loadings for the same scale to differ among age levels, so the test may be measuring different abilities at different age levels. Test materials consist of ten differently shaped wooden blocks and a…
USDA-ARS?s Scientific Manuscript database
In a previous study we showed that an Escherichia coli O157:H7 strain that was unable to form biofilm could persist in large numbers in dual-strain biofilms formed with an E. coli O-:H4 companion strain. In this study we tested additional companion strains for their ability to retain serotype O157:H...
Matthew H. Gocke; Daniel J. Robinson
2010-01-01
The ability to root stem cuttings collected from hedged stump sprouts formed on recently felled trees was evaluated for 26 codominant northern red oak (Quercus rubra L.) trees growing in Durham County, NC. Sprouting occurred, the same year as felling, on 23 of the 26 tree stumps and sprout number was significantly and positively correlated with stump diameter. The...
Aircraft Hangar Fire Suppression System Evaluation-Intermediate- Scale Studies
1999-12-23
aqueous film forming foam ( AFFF ) extinguishing systems [1]. The overhead AFFF system typically consists of standard closed head sprinklers that...of Water Spray on Fire-Fighting Foam ," Fire Journal, 63 (6), November 1969. 5. MIL-F-24385F, "Fire Extinguishing Agent, Aqueous Film Forming Foam ...extinguishing capability of the foam and the ability of the blanket to resist burnback. When AFFF is applied over a flammable liquid spill
ERIC Educational Resources Information Center
Gale, Catharine R.; Hatch, Stephani L.; Batty, G. David; Deary, Ian J.
2009-01-01
Lower cognitive ability is a risk factor for some forms of severe psychiatric disorder, but it is unclear whether it influences risk of psychological distress due to anxiety or the milder forms of depression. The participants in the present study were members of two British birth national birth cohorts, the 1958 National Child Development Survey…
Individual language experience modulates rapid formation of cortical memory circuits for novel words
Kimppa, Lilli; Kujala, Teija; Shtyrov, Yury
2016-01-01
Mastering multiple languages is an increasingly important ability in the modern world; furthermore, multilingualism may affect human learning abilities. Here, we test how the brain’s capacity to rapidly form new representations for spoken words is affected by prior individual experience in non-native language acquisition. Formation of new word memory traces is reflected in a neurophysiological response increase during a short exposure to novel lexicon. Therefore, we recorded changes in electrophysiological responses to phonologically native and non-native novel word-forms during a perceptual learning session, in which novel stimuli were repetitively presented to healthy adults in either ignore or attend conditions. We found that larger number of previously acquired languages and earlier average age of acquisition (AoA) predicted greater response increase to novel non-native word-forms. This suggests that early and extensive language experience is associated with greater neural flexibility for acquiring novel words with unfamiliar phonology. Conversely, later AoA was associated with a stronger response increase for phonologically native novel word-forms, indicating better tuning of neural linguistic circuits to native phonology. The results suggest that individual language experience has a strong effect on the neural mechanisms of word learning, and that it interacts with the phonological familiarity of the novel lexicon. PMID:27444206
The theory of multiple stupidities: education, technology and organisation in Arabia.
Al Lily, Abdulrahman Essa; Alhazmi, Ahmed Ali; Alzahrani, Saleh
2017-11-01
Traditional perspectives have envisaged intelligence as one entity dominated by a single set of abilities (i.e. cognitive abilities), whereas modern perspectives have defined intelligence in various shapes (e.g. linguistic, musical and interpersonal intelligences). By the same token, traditional perspectives have examined stupidity as one set of inabilities (i.e. cognitive inabilities). However, it is not clear whether modern perspectives have discussed whether stupidity exists in various forms-in the same way as they have envisaged intelligence. To address this limitation, 257 university members were asked to share what they perceived as being stupid educational and technological practices in their institutions. Analysis of the data suggested three concepts were important to the members: moral, spatial and administrative stupidities. That is, stupidity is perceived to come in the form of failing to meet certain moral, spatial and administrative values. This implies that modern perspectives may conceptualise stupidity differently from traditional perspectives, seeing it as going beyond cognitive inabilities and viewing it as existing in various forms (e.g. moral, spatial and administrative stupidities). Thus, there are multiple stupidities as there are multiple forms of intelligence. A strength of this research is that it views stupidity through an organisational and qualitative lens, although some may traditionally expect such a topic to be examined quantitatively through psychometric and biological approaches.
Evidence for Multiple Rhythmic Skills
Tierney, Adam; Kraus, Nina
2015-01-01
Rhythms, or patterns in time, play a vital role in both speech and music. Proficiency in a number of rhythm skills has been linked to language ability, suggesting that certain rhythmic processes in music and language rely on overlapping resources. However, a lack of understanding about how rhythm skills relate to each other has impeded progress in understanding how language relies on rhythm processing. In particular, it is unknown whether all rhythm skills are linked together, forming a single broad rhythmic competence, or whether there are multiple dissociable rhythm skills. We hypothesized that beat tapping and rhythm memory/sequencing form two separate clusters of rhythm skills. This hypothesis was tested with a battery of two beat tapping and two rhythm memory tests. Here we show that tapping to a metronome and the ability to adjust to a changing tempo while tapping to a metronome are related skills. The ability to remember rhythms and to drum along to repeating rhythmic sequences are also related. However, we found no relationship between beat tapping skills and rhythm memory skills. Thus, beat tapping and rhythm memory are dissociable rhythmic aptitudes. This discovery may inform future research disambiguating how distinct rhythm competencies track with specific language functions. PMID:26376489
Complete genome sequence of Methanospirillum hungatei type strain JF1
Gunsalus, Robert; Cook, Lauren E.; Crable, Bryan R.; ...
2016-01-06
Methanospirillum hungatei strain JF1 (DSM 864) is a methane-producing archaeon and is the type species of the genus Methanospirillum, which belongs to the family Methanospirillaceae within the order Methanomicrobiales. Its genome was selected for sequencing due to its ability to utilize hydrogen and carbon dioxide and/or formate as a sole source of energy. Ecologically, M. hungatei functions as the hydrogen- and/or formate-using partner with many species of syntrophic bacteria. Its morphology is distinct from other methanogens with the ability to form long chains of cells (up to 100 m in length), which are enclosed within a sheath-like structure, and terminalmore » cells with polar flagella. The genome of M. hungatei strain JF1 is the first completely sequenced genome of the family Methanospirillaceae, and it has a circular genome of 3,544,738 bp containing 3,239 protein coding and 68 RNA genes. Furthermore, the large genome of M. hungatei JF1 suggests the presence of unrecognized biochemical/physiological properties that likely extend to the other Methanospirillaceae and include the ability to form the unusual sheath-like structure and to successfully interact with syntrophic bacteria.« less
Guennoc, Cora Miquel; Rose, Christophe; Labbé, Jessy; Deveau, Aurélie
2018-05-17
Ectomycorrhizal (ECM) fungi establish symbiosis with roots of most trees of boreal and temperate ecosystems and are major drivers of nutrient fluxes between trees and the soil. ECM fungi constantly interact with bacteria all along their life cycle and the extended networks of hyphae provide a habitat for complex bacterial communities. Despite the important effects these bacteria can have on the growth and activities of ECM fungi, little is known about the mechanisms by which these microorganisms interact. Here we investigated the ability of bacteria to form biofilm on the hyphae of the ECM fungus Laccaria bicolor. We showed that the ability to form biofilms on the hyphae of the ECM fungus is widely shared among soil bacteria. Conversely, some fungi, belonging to the Ascomycete class, did not allow for the formation of bacterial biofilms on their surfaces. The formation of biofilms was also modulated by the presence of tree roots and ectomycorrhizae, suggesting that biofilm formation does not occur randomly in soil but that it is regulated by several biotic factors. In addition, our study demonstrated that the formation of bacterial biofilm on fungal hyphae relies on the production of networks of filaments made of extracellular DNA.
Khurana, Atika; Romer, Daniel; Betancourt, Laura M.; Brodsky, Nancy L.; Giannetta, Joan M.; Hurt, Hallam
2013-01-01
Although deficits in working memory ability have been implicated in suboptimal decision making and risk taking among adolescents, its influence on early sexual initiation has so far not been examined. Analyzing 2 waves of panel data from a community sample of adolescents (N = 347; Mean age[baseline] = 13.4 years), assessed 1 year apart, the present study tested the hypothesis that weak working memory ability predicts early sexual initiation and explored whether this relationship is mediated by sensation seeking and 2 forms of impulsivity, namely acting-without-thinking and temporal discounting. The 2 forms of impulsivity were expected to be positively associated with early sexual initiation, whereas sensation seeking was hypothesized to be unrelated or to have a protective influence, due to its positive association with working memory. Results obtained from structural equation modeling procedures supported these predictions and in addition showed that the effects of 3 prominent risk factors (Black racial identity, low socioeconomic background, and early pubertal maturation) on early sexual initiation were entirely mediated by working memory and impulsivity. The findings are discussed in regard to their implications for preventing early sexual onset among adolescents. PMID:22369334
Dopaminergic influences on formation of a motor memory.
Flöel, Agnes; Breitenstein, Caterina; Hummel, Friedhelm; Celnik, Pablo; Gingert, Christian; Sawaki, Lumy; Knecht, Stefan; Cohen, Leonardo G
2005-07-01
The ability of the central nervous system to form motor memories, a process contributing to motor learning and skill acquisition, decreases with age. Dopaminergic activity, one of the mechanisms implicated in memory formation, experiences a similar decline with aging. It is possible that restoring dopaminergic function in elderly adults could lead to improved formation of motor memories with training. We studied the influence of a single oral dose of levodopa (100mg) administered preceding training on the ability to encode an elementary motor memory in the primary motor cortex of elderly and young healthy volunteers in a randomized, double-blind, placebo-controlled design. Attention to the task and motor training kinematics were comparable across age groups and sessions. In young subjects, encoding a motor memory under placebo was more prominent than in older subjects, and the encoding process was accelerated by intake of levodopa. In the elderly group, diminished motor memory encoding under placebo was enhanced by intake of levodopa to levels present in younger subjects. Therefore, upregulation of dopaminergic activity accelerated memory formation in young subjects and restored the ability to form a motor memory in elderly subjects; possible mechanisms underlying the beneficial effects of dopaminergic agents on motor learning in neurorehabilitation.
Cirlini, Martina; Generotti, Silvia; Dall'Erta, Andrea; Lancioni, Pietro; Ferrazzano, Gianluca; Massi, Andrea; Galaverna, Gianni; Dall'Asta, Chiara
2013-12-24
Deoxynivalenol (DON) is the most prevalent trichothecene in Europe and its occurrence is associated with infections of Fusarium graminearum and F. culmorum, causal agents of Fusarium head blight (FHB) on wheat. Resistance to FHB is a complex character and high variability occurs in the relationship between DON content and FHB incidence. DON conjugation to glucose (DON-3-glucoside, D3G) is the primary plant mechanism for resistance towards DON accumulation. Although this mechanism has been already described in bread wheat and barley, no data are reported so far about durum wheat, a key cereal in the pasta production chain. To address this issue, the ability of durum wheat to detoxify and convert deoxynivalenol into D3G was studied under greenhouse controlled conditions. Four durum wheat varieties (Svevo, Claudio, Kofa and Neodur) were assessed for DON-D3G conversion; Sumai 3, a bread wheat variety carrying a major QTL for FHB resistance (QFhs.ndsu-3B), was used as a positive control. Data reported hereby clearly demonstrate the ability of durum wheat to convert deoxynivalenol into its conjugated form, D3G.
2010-01-01
Background The Generalist Genes Hypothesis is based upon quantitative genetic findings which indicate that many of the same genes influence diverse cognitive abilities and disabilities across age. In a recent genome-wide association study of mathematical ability in 10-year-old children, 43 SNP associations were nominated from scans of pooled DNA, 10 of which were validated in an individually genotyped sample. The 4927 children in this genotyped sample have also been studied at 7, 9 and 12 years of age on measures of mathematical ability, as well as on other cognitive and learning abilities. Results Using these data we have explored the Generalist Genes Hypothesis by assessing the association of the available measures of ability at age 10 and other ages with two composite 'SNP-set' scores, formed from the full set of 43 nominated SNPs and the sub-set of 10 SNPs that were previously found to be associated with mathematical ability at age 10. Both SNP sets yielded significant associations with mathematical ability at ages 7, 9 and 12, as well as with reading and general cognitive ability at age 10. Conclusions Although effect sizes are small, our results correspond with those of quantitative genetic research in supporting the Generalist Genes Hypothesis. SNP sets identified on the basis of their associations with mathematical ability at age 10 show associations with mathematical ability at earlier and later ages and show associations of similar magnitude with reading and general cognitive ability. With small effect sizes expected in such complex traits, future studies may be able to capitalise on power by searching for 'generalist genes' using longitudinal and multivariate approaches. PMID:20602751
49 CFR 212.201 - General qualifications of State inspection personnel.
Code of Federal Regulations, 2011 CFR
2011-10-01
... acceptable; (3) The ability to record data on standard report forms with a high degree of accuracy; (4) The..., and terminology common to operating and maintenance functions; and (2) The scope and major...
49 CFR 212.201 - General qualifications of State inspection personnel.
Code of Federal Regulations, 2010 CFR
2010-10-01
... acceptable; (3) The ability to record data on standard report forms with a high degree of accuracy; (4) The..., and terminology common to operating and maintenance functions; and (2) The scope and major...
... inserted through the skin into the muscle. Each muscle fiber that contracts will produce an action potential. The presence, size, and shape of the wave form of the action potential ... the ability of the muscle to respond to nervous stimulation.
Endocytic vesicle rupture is a conserved mechanism of cellular invasion by amyloid proteins.
Flavin, William P; Bousset, Luc; Green, Zachary C; Chu, Yaping; Skarpathiotis, Stratos; Chaney, Michael J; Kordower, Jeffrey H; Melki, Ronald; Campbell, Edward M
2017-10-01
Numerous pathological amyloid proteins spread from cell to cell during neurodegenerative disease, facilitating the propagation of cellular pathology and disease progression. Understanding the mechanism by which disease-associated amyloid protein assemblies enter target cells and induce cellular dysfunction is, therefore, key to understanding the progressive nature of such neurodegenerative diseases. In this study, we utilized an imaging-based assay to monitor the ability of disease-associated amyloid assemblies to rupture intracellular vesicles following endocytosis. We observe that the ability to induce vesicle rupture is a common feature of α-synuclein (α-syn) assemblies, as assemblies derived from WT or familial disease-associated mutant α-syn all exhibited the ability to induce vesicle rupture. Similarly, different conformational strains of WT α-syn assemblies, but not monomeric or oligomeric forms, efficiently induced vesicle rupture following endocytosis. The ability to induce vesicle rupture was not specific to α-syn, as amyloid assemblies of tau and huntingtin Exon1 with pathologic polyglutamine repeats also exhibited the ability to induce vesicle rupture. We also observe that vesicles ruptured by α-syn are positive for the autophagic marker LC3 and can accumulate and fuse into large, intracellular structures resembling Lewy bodies in vitro. Finally, we show that the same markers of vesicle rupture surround Lewy bodies in brain sections from PD patients. These data underscore the importance of this conserved endocytic vesicle rupture event as a damaging mechanism of cellular invasion by amyloid assemblies of multiple neurodegenerative disease-associated proteins, and suggest that proteinaceous inclusions such as Lewy bodies form as a consequence of continued fusion of autophagic vesicles in cells unable to degrade ruptured vesicles and their amyloid contents.
The role of MMP-1 in breast cancer growth and metastasis to the brain in a xenograft model.
Liu, Hui; Kato, Yukinari; Erzinger, Stephanie A; Kiriakova, Galina M; Qian, Yongzhen; Palmieri, Diane; Steeg, Patricia S; Price, Janet E
2012-12-07
Brain metastasis is an increasingly common complication for breast cancer patients; approximately 15- 30% of breast cancer patients develop brain metastasis. However, relatively little is known about how these metastases form, and what phenotypes are characteristic of cells with brain metastasizing potential. In this study, we show that the targeted knockdown of MMP-1 in breast cancer cells with enhanced brain metastatic ability not only reduced primary tumor growth, but also significantly inhibited brain metastasis. Two variants of the MDA-MB-231 human breast cancer cell line selected for enhanced ability to form brain metastases in nude mice (231-BR and 231-BR3 cells) were found to express high levels of matrix metalloproteinase-1 (MMP-1). Short hairpin RNA-mediated stable knockdown of MMP-1 in 231-BR and 231-BR3 cells were established to analyze tumorigenic ability and metastatic ability. Short hairpin RNA-mediated stable knockdown of MMP-1 inhibited the invasive ability of MDA-MB 231 variant cells in vitro, and inhibited breast cancer growth when the cells were injected into the mammary fat pad of nude mice. Reduction of MMP-1 expression significantly attenuated brain metastasis and lung metastasis formation following injection of cells into the left ventricle of the heart and tail vein, respectively. There were significantly fewer proliferating cells in brain metastases of cells with reduced MMP-1 expression. Furthermore, reduced MMP-1 expression was associated with decreased TGFα release and phospho-EGFR expression in 231-BR and BR3 cells. Our results show that elevated expression of MMP-1 can promote the local growth and the formation of brain metastases by breast cancer cells.
Brunne, Viviane
2009-09-01
In the face of the extreme challenges posed by the South African HIV/AIDS epidemic, collaboration between public and private partners is often called for in an attempt to mobilise additional resources and generate synergies. This paper shows that the ability to successfully use public-private partnerships to address complex challenges, such as an HIV/AIDS epidemic, is influenced by the fabric of society, one important aspect being historical legacies. The first part of the article shows how South Africa's apartheid past affects the ability of public and private partners to collaborate in a response to HIV and AIDS today. It also takes into account how reconciliation and nation-building policies in the immediate post-transformation period have affected the ability to form and sustain partnerships concerning HIV/AIDS issues. The second part of the article analyses more recent developments regarding the information that these hold as to the feasibility of public-private partnerships and whether these continue to be affected by the legacies of the past. Two events with symbolic political value in South Africa, namely the 2010 FIFA World Cup soccer event and the recent changes in government, are systematically examined on the basis of three analytical queries, regarding: the impact of the event on nation-building and transcending cleavages in society; the event's impact on the ability to form public-private partnerships in general; and the role of HIV/AIDS in connection with the event. Conclusions are drawn a propos the influence of historic factors on the ability of South African society to effectively use public-private partnerships in the response to HIV and AIDS, and the continued dynamics and likely future directions of these partnerships.