Changes In Shapes Research Articles

Dynamic cellular finite-element method for modelling large-scale cell migration and proliferation under the control of mechanical and biochemical cues: a study of re-epithelialization.

Computational modelling of cells can reveal insight into the mechanisms of the important processes of tissue development. However, current cell models have limitations and are challenged to model detailed changes in cellular shapes and physical mechanics when thousands of migrating and interacting cells need to be modelled. Here we describe a novel dynamic cellular finite-element model (DyCelFEM), which accounts for changes in cellular shapes and mechanics. It also models the full range of cell motion, from movements of individual cells to collective cell migrations. The transmission of mechanical forces regulated by intercellular adhesions and their ruptures are also accounted for. Intra-cellular protein signalling networks controlling cell behaviours are embedded in individual cells. We employ DyCelFEM to examine specific effects of biochemical and mechanical cues in regulating cell migration and proliferation, and in controlling tissue patterning using a simplified re-epithelialization model of wound tissue. Our results suggest that biochemical cues are better at guiding cell migration with improved directionality and persistence, while mechanical cues are better at coordinating collective cell migration. Overall, DyCelFEM can be used to study developmental processes when a large population of migrating cells under mechanical and biochemical controls experience complex changes in cell shapes and mechanics.

Study on Structural and Fatigue Analysis according to Shape change of Automatic Press

In the present study, the structural and fatigue analysis on the shape change of an automatic press are investigated for prediction of operation safety and reliability of the automatic press along the thickness(t) and length(L) of head, and corner shapes(case 1, 2, 3). The equivalent stress and deformation characteristics of the automatic press were studied by computerized analysis method for the bushing production of the seat frame. An external stress of 14.0 MPa was applied to predict the operation stability and the fatigue limit of the structure. As the thickness of the header increased and the length of the header decreased, the load stability applied by the piston improved and the maximum stress and deformation were reduced. In addition, due to the change in shape of the corners, the load applied at the cross-sectional area of the corners decreases, and then the maximum stress and deformation appearing in the header are reduced. That is, the change of corner shapes affects the equivalent stress and deformation. That is the change of corner shapes affects the equivalent stress and deformation. From the fatigue and vibration analysis, fatigue failure does not occur even when the number of alternating operation of the automatic press increases, and the natural frequency is predicted for dynamic characteristics.

Tomelleri, Vittorio Springfield and Kempgen, Sebastian (eds) Slavic Alphabets in Contact (review)

Slavonic and East European Review, 95, 2, 2017 Reviews Tomelleri, Vittorio Springfield and Kempgen, Sebastian (eds). Slavic Alphabets in Contact. Bamberger Beiträger zur Linguistik, 7. University of Bamberg Press, Bamberg, 2015. xv + 305 pp. Maps. Illustrations. Figures. Tables. Bibliographies. Notes. €20.00 (paperback). This collection of articles arose from a panel devoted to Slavic alphabets in contact situations at the 11th Meeting of German Slavicists, held in October 2012 at the Dresden University of Technology. Subsequently, the organizers invited other colleagues to contribute to the volume which here consists of twelve articles written in German, English, French, Russian, Ukrainian and Belarusian. With the number of topics covered being exceptionally broad and important for furthering our knowledge about orthographic systems in general, the articles deal with both the contemporary and historical vicissitudes of Slavic alphabets used across continental Europe and on its periphery. Daniel Bunčić, who had been one of the organizers of the aforementioned panel, could not contribute to the volume due to academic obligations and his work on a project elaborating on the sociolinguistic typology of biscriptality (Winter Verlag, 2016). By outlining different aspects of contact situations for Slavic alphabets in their introduction, the editors remind us, and rightly so, that we still tend to consider Cyrillic as intrinsically a product of Slavic heritage, while the Latin script does not enjoy the status of a native Slavic system (p. viii). Taking this remark as a guideline, Vladimir Alpatov examines the vagaries of the creation of new Latin-based scripts in the 1920s–30s for most of the minority languages spoken in the Soviet Union (pp. 1–11). He focuses on the 1930 experiment of introducing a Latin-based writing system for Russian by a group of linguists headed by Nikolai Iakovlev, which was ultimately rejected due to changes in the political and ideological situation in the country and abroad. Today, the author surmises, the introduction of Latin script in Russia is totally impossible because of ‘the century-old habits and traditions of many million speakers of Russian’, although Iakovlev’s forgotten script still can be employed as an auxiliary (p. 10). Another fragment of Soviet language building in the 1920s–30s is presented by Elena Simonato, who addresses the creation of a Latin-based script by Dmitrii Bubrikh for Karelian (pp. 13–32). According to the author, claiming today that the choice of either Cyrillic or Latin-based script for a minority language in Soviet times was not ideological but contingent, is open to doubt. For instance, working on a script for Karelian, Bubrikh deemed it necessary to determine whether Karelian was a dialect of Finnish or a separate language. Also, since Karelian was spoken in Karelia itself and in the Tver´ region, Bubrikh had to decide which of the two languages required an orthographic system (p. 20). SEER, 95, 2, APRIL 2017 342 Sebastian Kempgen offers an overview of recent changes in Cyrillic as employed in public spheres in Bulgaria, Macedonia and Russia (pp. 33–58). Being descriptive, even ‘graphic’ at its core, with twenty-four colourful illustrations, his study is primarily concerned with ‘visual’ transformations in the ‘script morphology’, encompassing changes in letter shapes and even the use of Latin characters instead of Cyrillic ones (pp. 42–45). However, the author’s conclusion that these changes were engendered earlier in the periphery (Bulgaria and Macedonia) (p. 47) lacks grounding; his research does not furnish any data on the eventual changes that took place in the ‘script morphology’ of Ukrainian and Belarusian. The next article, by Bernhard Brehmer, looks into script-switching as practised by Slavic-German bilinguals participating in multilingual discussion groups in the social network studivz (pp. 59–94). Having researched postings generated by Bulgarians, Russians and Ukrainians living in the German-speaking milieu, the author draws a rather obvious conclusion that Cyrillic is used to signal their ‘linguistic-cultural belonging’ to the Slavic community (p. 88). Elena Surkova’s study focuses on the history of orthographic systems as used in the Belarusian lands from the inception of literacy among the East Slavs to the publication of the Belarusian grammar by Bronislav Tarashkevich in 1918 (pp. 95–130). Offering a sweeping survey of the...

Surfactant concentration dependent metachromasy of an anionic cyanine dye in adsorbed and deposited Langmuir films

This communication reports the metachromasy or the changes in shapes and positions of the absorption spectra of an anionic cyanine dye merocyanine 540 abbreviated as MC540, in aqueous solutions and in LB films when electrostatically interacted with a well-known cationic surfactant cetyltrimethylammonium bromide abbreviated as CTAB. Critical Micellar Concentration of CTAB affected largely on the dissociation of MC540 molecular aggregates in the CTAB-MC540 complex LB films. Spectroscopic studies of these LB films showed only monomeric absorption band and intense fluorescence band. This complex LB film can act as efficient fluorescence probe for several biological systems.

Study of optical absorbance and MR relaxation of Fricke xylenol orange gel dosimeters

Studies on the optical absorbance spectra of Fricke xylenol orange gel dosimeters were performed, in the wavelength range from 300 nm to 800 nm, in order to highlight some particular characteristics that can affect the achievable precision. The spectra are different mainly due to the different types of xylenol orange that was used and to a lower extent due to the different gelling agents (agarose or gelatine). The characteristic of variation of absorbance spectra versus dose, however, are similar in the various cases and can explain some peculiarities, as apparent effects of dose threshold. Changes of spectral shapes appear over the time after irradiation. Magnetic resonance measurements performed at various times after irradiation only reveal the slow changes due to the auto-oxidation effect, proving therefore that the modality of chelation of ferric ions by xylenol orange can affect the observed changes in the optical absorbance spectra.

Optical properties of plasmonic silver nanoparticles exposed to organic solvents

The influence of ethanol and acetic acid on the structure and optical properties of silver granular films formed by physical vapor deposition in a high vacuum on sapphire substrates was studied via optical spectroscopy and scanning electron microscopy. It was found that irregularly shaped oblate silver grains transforms into almost spherical nanoparticles. Simultaneously, optical extinction spectra shift in the short wavelength range and become narrower. The same effect was observed when liquid crystal was poured on such film. It was noticed, that nanoparticle shapes change under the action of these fluids in the same way as in the process of thermal annealing. This analogy suggests that the observed effects could be explained by acceleration of atomic diffusion over the islet surfaces. It was noticed also that the resistance of thick granular films changes abruptly several minutes after pouring such film with ethanol. This jump of resistance is also very similar to the resistance jump observed previously in the case of annealing.

Wind pressures on different roof shapes of a finite height circular cylinder

The effects of finite cylinder free end shape on the mean and fluctuating wind pressures were investigated experimentally and numerically by using three different roof shapes: flat, conical and hemispherical. The pressure distributions on the roofs and the side walls of the finite cylinders partially immersed in a simulated atmospheric boundary layer have been obtained for three different roof shapes. Realizable <TEX>$k-{\varepsilon}$</TEX> turbulence model was used for numerical simulations. Change in roof shapes has caused significant differences on the pressure distributions. When compared the pressure distributions on the different roofs, it is seen from the results that hemispherical roof has the most critical pressure field among the others. It is found a good agreement between numerical and experimental results.

A Combinatorial Reasoning Mechanism with Topological and Metric Relations for Change Detection in River Planforms: An Application to GlobeLand30’s Water Bodies

Changes in river plane shapes are called river planform changes (RPCs). Such changes can impact sustainable human development (e.g., human habitations, industrial and agricultural development, and national border security). RPCs can be identified through field surveys—a method that is highly precise but time-consuming, or through remote sensing (RS) and geographic information system (GIS), which are less precise but more efficient. Previous studies that have addressed RPCs often used RS, GIS, or digital elevation models (DEMs) and focused on only one or a few rivers in specific areas with the goal of identifying the reasons underlying these changes. In contrast, in this paper, we developed a combinatorial reasoning mechanism based on topological and metric relations that can be used to classify RPCs. This approach does not require DEMs and can eliminate most false-change information caused by varying river water levels. First, we present GIS models of river planforms based on their natural properties and, then, modify these models into simple GIS river planform models (SGRPMs) using straight lines rather than common lines to facilitate computational and human understanding. Second, we used double straight line 4-intersection models (DSL4IMs) and intersection and difference models (IDMs) of the regions to represent the topological relations between the SGRPMs and used double-start-point 8-distance models (DS8DMs) to express the metric relations between the SGRPMs. Then, we combined topological and metric relations to analyse the changes in the SGRPMs. Finally, to compensate for the complexity of common river planforms in nature, we proposed three segmentation rules to turn common river planforms into SGRPMs and used combinatorial reasoning mechanism tables (CRMTs) to describe the spatial relations among different river planforms. Based on our method, users can describe common river planforms and their changes in detail and confidently reject false changes. Future work should develop a method to automatically or semi-automatically adjust the segmentation rules and the combinatorial reasoning mechanism.

Memory formation orchestrates the wiring of adult-born hippocampal neurons into brain circuits.

During memory formation, structural rearrangements of dendritic spines provide a mean to durably modulate synaptic connectivity within neuronal networks. New neurons generated throughout the adult life in the dentate gyrus of the hippocampus contribute to learning and memory. As these neurons become incorporated into the network, they generate huge numbers of new connections that modify hippocampal circuitry and functioning. However, it is yet unclear as to how the dynamic process of memory formation influences their synaptic integration into neuronal circuits. New memories are established according to a multistep process during which new information is first acquired and then consolidated to form a stable memory trace. Upon recall, memory is transiently destabilized and vulnerable to modification. Using contextual fear conditioning, we found that learning was associated with an acceleration of dendritic spines formation of adult-born neurons, and that spine connectivity becomes strengthened after memory consolidation. Moreover, we observed that afferent connectivity onto adult-born neurons is enhanced after memory retrieval, while extinction training induces a change of spine shapes. Together, these findings reveal that the neuronal activity supporting memory processes strongly influences the structural dendritic integration of adult-born neurons into pre-existing neuronal circuits. Such change of afferent connectivity is likely to impact the overall wiring of hippocampal network, and consequently, to regulate hippocampal function.

From carbon dots to multipods — The role of nickel particle shape and size

In an attempt to synthesize carbon tripod structures in high yield, we have observed that a wide range of carbon structures are formed as the Ni particle size and shape varied. In using trichloroethylene (TCE), acetylene and their mixtures as a carbon source to make carbon materials over Ni nanoparticle catalysts in a chemical vapor deposition (CVD) process, we have observed that the Ni particle size and shape impacts dramatically on the carbon structure formed. The synthesis of the Ni catalyst was achieved by reduction of Ni(acetate)2 with hydrazine (35%). Ex-situ TEM analysis of the reduced NiO particles revealed that the Ni particles underwent a morphological change in the presence of TCE (and H2) with change in (i) temperature (350–750°C) and (ii) H2 flow rate (20–150mL/min) and that this affected the shape of the carbon material that formed. In the absence of TCE only particle sintering occurred. At T=350°C the Ni particles are covered by carbon to form carbon dots. With an increase in T the carbon shapes changed to a bimodal (400°C) and then to a tripod-like structure (450°C) and eventually multipod-like structures (500°C). Carbon fibers were mainly observed for T>500°C. Similar shape changes were observed at 450°C as a function of reaction time and H2 flow rate. It was also found that when acetylene or an acetylene/trichloroethylene mixture was used at T=450°C, helical and linear fibers were produced. The TEM data reveal that the fragmentation and sintering of the Ni (by the carbon source and other factors) to give differently sized Ni particles, especially as it is affected by H2, determines the morphology of the carbon materials grown from the Ni. The TCE has the ability to restructure the Ni particles and this leads to the unusual carbon shapes observed. Thus the carbon and the catalyst influence each other during the growth of the carbon materials.

MPM with Frictional Contact for Application to Soft Particulate Materials

Soft particle materials are composed of discrete particles that can undergo large deformations without rupture. Most food products, many powders, colloidal pastes, vesicles and biological cells are soft particle systems. In order to model such materials, we present an efficient numerical approach combining an implicit formulation of the Material Point Method (MPM) and Contact Dynamics (CD) method. The MPM deals with bulk variables of an individual particle by discretizing it as a collection of material points, whereas the CD allows for the treatment of frictional contacts between particles. This model is applied for the simulation of the uniaxial compression of 2D soft-particle packings. The compaction is a nonlinear process in which new contacts are formed between particles and the contact areas increase. The change of particle shapes allows these materials to reach high packing fraction. We find that the contact specific surface, the orientation anisotropy and the aspect ratio of particles increase as a function of the packing fraction but at different rates. We also evidence the effect of friction, which favors strong stress chains and thus the elongation of particles, leading to larger values of the orientation anisotropy and the aspect ratio at a given level of packing fraction as compared to a frictionless particle packing.

Modal strain identification using sub-microstrain FBG data from a pre-stressed concrete beam during progressive damage testing

Vibration-based damage identification can constitute a successful approach for Structural Health Monitoring (SHM) of civil structures. It is a non-destructive condition assessment method, dependent on the identification of changes in the modal characteristics of a structure that are related to damage. However, the damage identification from the modal characteristics of existing structures currently suffers from a low sensitivity of eigenfrequencies and mode shapes to certain types of damage. Furthermore, the sensitivity of eigenfrequencies to environmental influences may be sufficiently high to completely mask the effect even of severe damage. Modal strains and curvatures are more sensitive to local damage, but the direct monitoring of these quantities is challenging when the strain level is very low. In the present work, the identification of the modal strains of a pre-stressed concrete beam, subjected to a progressive damage test, is performed. Dynamic measurements are conducted on the beam at the beginning of each cycle and its response is recorded with multiplexed Fiber-optic Bragg Grating (FBG) strain sensors. Bending, lateral and torsional modes are accurately identified from dynamic strains with a typical measured root mean square (RMS) strain value of about 0.35 micro-strains. The evolution of the modal characteristics of the beam after each loading cycle is investigated. Changes of the eigenfrequency values, the amplitude and the curvature of the strain mode shapes are observed. The changes in the strain mode shapes appear at the locations where the damage is induced, and are already identified from an early damaged state.

Free vibration analysis of smart composite beam

The integration of composite beam with piezoelectric materials has been under a considerable attention to obtain active lightweight material. Smart materials will control the system in terms of reducing the vibrations amplitude and frequency so as to improve the efficiency of the system. Piezoelectric materials are often used to design smart structures in industrial, medical, military and scientific areas. The aim of the present study is to study the free vibration behaviour of a smart composite beam structure. Smart beam consists of composite beam modelled in cantilever configuration with PZT patches. The modal analysis of the smart cantilever beam was performed using the ANSYS software to reveal the fundamental modal frequencies and modal shapes. It can be inferred that the Modal analysis performed is usefull for applications in structural health monitoring of the smart composite structures. The changes in the mode shapes are used as an indicator to ascertain the damage to the smart composte beam structure.

Hierarchical organization in visual working memory: From global ensemble to individual object structure

When remembering a natural scene, both detailed information about specific objects and summary representations such as the gist of a scene are encoded. However, formal models of change detection that are used to estimate working memory capacity, typically assume observers simply encode and maintain memory representations that are treated independently from one another without considering the (hierarchical) object or scene structure. To overcome this limitation, we present a hierarchical variant of the change detection task that attempts to formalize the role of object structure, thus, allowing for richer, more graded memory representations. We demonstrate that detection of a global-object change precedes local-object changes of hierarchical shapes to a large extent. Moreover, when systematically varying object repetitions between individual items at a global or a local level, memory performance declines mainly for repeated global objects, but not for repeated local objects, which suggests that ensemble (i.e., summary) representations are likewise biased toward a global level. In addition, this global memory precedence effect is shown to be independent from encoding durations, and mostly cannot be attributed to differences in saliency or shape discriminability at global/local object levels. This pattern of results is suggestive of a global/local difference occurring primarily during memory maintenance. Altogether, these findings challenge visual-working-memory (vWM) models that propose that a fixed number of objects can be remembered regardless of the individual object structure. Instead, our results support a hierarchical model that emphasizes the role for structured representations among objects in vWM.

Numerical investigation of the effect of boundary conditions on hydroelastic stability of two parallel plates interacting with a layer of ideal flowing fluid

The paper studies the hydroelastic stability of two parallel identical rectangular plates interacting with a flowing fluid confined between them. General equations describing the behavior of ideal compressible liquid in the case of small perturbations are written in terms of the perturbation velocity potential and transformed using the Bubnov–Galerkin method. The small deformations of elastic plates are defined using the first-order shear deformation plate theory. A mathematical formulation of the dynamic problem for elastic structures is developed using the variational principle of virtual displacements, which takes into account the work done by the inertial forces and hydrodynamic pressure. The numerical solution of the problem is carried out in three-dimensional formulation by means of the finite element method. A stability criterion is based on the analysis of complex eigenvalues of the coupled system of equations obtained for different values of flow velocity. The existence of different types of instability has been shown depending on the combinations of the kinematic boundary conditions defined at the edges of both plates. We considered both the symmetric and asymmetric types of clamping. It has been found that the dependence of the lowest eigenfrequency of two parallel plates on the height of quiescent fluid is nonmonotonic with a pronounced peak. At the same time, critical velocities of instability change insignificantly if the distance between plates is greater than half of the maximum linear dimensions of the structure. It should be noted that the critical velocities of divergence increase monotonically with growth of the height of the fluid layer, but critical velocities for the onset of flutter instability have sharp jumps. The cause of these jumps is a change in the mode shapes at which the system loses stability.

Crack-tip shape in the crack-growth rate transition of filled elastomers

The velocity transition in crack-growth dynamics and the accompanying changes in crack tip shapes are investigated for the elastomers composed of styrene-butadiene rubber and silica filler (SBR/SI). The concentrations of filler and cross-link (ϕf and cx, respectively), and temperature (T) are extensively varied in order to change the degree of nonlinearity in elasticity of the elastomers. The shapes of the crack tip are characterized by three parameters, i.e., the deviation δ from the parabolic one expected by the linear elastic fracture mechanics (LEFM), the parabolic curvature a, and the non-dimensional quantity aδ. The dependence of these parameters on the input tearing energy Γ is successfully explained by the weakly nonlinear theory of dynamic fracture (WNLT), which considers the contribution of the second-order shear modulus μ(2) to the strain field in addition to that of the first-order shear modulus μ(1), independently of ϕf, cx and T, unless δ exceeds a limit value (δC). SBR/SI shows an appreciably larger value of δC than the carbon-black filled acrylonitrile butadiene (NBR/CB) elastomers. The smaller value of δC for NBR/CB is attributed to that the contribution of the third-order nonlinear modulus μ(3)/μ(1), which is not considered in WNLT, is appreciably higher than that in SBR/SI. The magnitude of the threshold tearing energy Γc for the onset of the velocity transition shows a good correlation with the fracture toughness Wc normalized by the nonlinear elastic constant μ(1)3/μ(2)2 in WNLT. This result indicates that the magnitude is governed by the combined effect of the degree of nonlinearity in elasticity and the fracture toughness.

Experimental investigation on the mechanism of pressure oscillation for steam jet in stable condensation region

The pressure oscillations for steam jet in stable condensation region are investigated experimentally. Steam at pressure 0.2–0.6MPa is injected into subcooled water at one atmosphere pressure with steam mass flux ranging from 298 to 865kg/(m2s), with water subcooling from 70 to 40K. The steam plume shapes have been recorded and are compared with the pressure oscillation. The pressure oscillation for steam jet in stable condensation region is caused by the oscillation of steam plume length. When the steam plume length is the longest, the pressure oscillation has negative peak value and vice versa. Based on the experimental data and the change of steam plume shapes, a new phenomenological model of pressure oscillation is developed. The model also provides a method to obtain the steam plume length using the pressure oscillation. The prediction errors of the peak pressure oscillation are within ±30% of experimental values.

Influence of Icing on the Modal Behavior of Wind Turbine Blades

Wind turbines installed in cold climate sites accumulate ice on their structures. Icing of the rotor blades reduces turbine power output and increases loads, vibrations, noise, and safety risks due to the potential ice throw. Ice accumulation increases the mass distribution of the blade, while changes in the aerofoil shapes affect its aerodynamic behavior. Thus, the structural and aerodynamic changes due to icing affect the modal behavior of wind turbine blades. In this study, aeroelastic equations of the wind turbine blade vibrations are derived to analyze modal behavior of the Tjaereborg 2 MW wind turbine blade with ice. Structural vibrations of the blade are coupled with a Beddoes-Leishman unsteady attached flow aerodynamics model and the resulting aeroelastic equations are analyzed using the finite element method (FEM). A linearly increasing ice mass distribution is considered from the blade root to half-length and thereafter constant ice mass distribution to the blade tip, as defined by Germanischer Lloyd (GL) for the certification of wind turbines. Both structural and aerodynamic properties of the iced blades are evaluated and used to determine their influence on aeroelastic natural frequencies and damping factors. Blade natural frequencies reduce with ice mass and the amount of reduction in frequencies depends on how the ice mass is distributed along the blade length; but the reduction in damping factors depends on the ice shape. The variations in the natural frequencies of the iced blades with wind velocities are negligible; however, the damping factors change with wind velocity and become negative at some wind velocities. This study shows that the aerodynamic changes in the iced blade can cause violent vibrations within the operating wind velocity range of this turbine.

Characterization of stressing conditions in mills – A comprehensive research strategy based on well-characterized model particles

Despite the abundant industrial use of various wet mills a detailed understanding of the mechanisms involved is far from being complete. During comminution stress distributions are applied to the individual particles of a processed suspension. In fact, the type of stressing and the acting stress energies are distributed. The distributions of acting stress energy and number of stress events per product particle are governed by the used mill and its operational conditions. Mill functions link the stress energy and stress number distributions to the operating parameters and are so far unknown. We introduce a new methodology to directly characterize the effective stress energy and effective stress number distributions within stirred media mills: Mechanically fully characterized spherical particles are used as particulate probes. The underlying finite element model for the energetic behavior of the probes during uniaxial compression is supported by manipulation experiments on the single particle level. The deformation behavior of individual particles and the respective changes of the particles' shapes are used to determine the stressing history of the particles and hence the stress energy and stress number distributions in the mill. Experimental limitations and prospects of the proposed methodology are outlined in detail. The new approach is comprehensively discussed for a lab-scale stirred media mill operated at exemplary process conditions. The transfer to other mills or unit operations, however, is straightforward.

Deformation and shape changes inW167

Lifetime measurements of yrast levels in $^{167}\mathrm{W}$ were measured using the recoil-distance Doppler-shift method. The differential decay-curve method was applied for a lifetime determination. Excited states of the nucleus $^{167}\mathrm{W}$ were populated by the reaction $^{142}\mathrm{Nd}$ ($^{28}\mathrm{Si}, 3n$) at a beam energy of 144 MeV. The energy spectra and measured transition quadrupole moments inferred from the lifetimes of $^{167}\mathrm{W}$ are compared with the predictions of the cranked Nilsson-Strutinsky-Bogoliubov calculations. The changes of deformations and shapes with increasing spin due to the $\ensuremath{\gamma}$-polarization effect of aligned particles are discussed. The signature inversion visible in the negative parity yrast band is explained to be related to the triaxial shapes.