Presence Of Attraction Research Articles

Pengembangan Cagar Budaya Wisata Religi Asta Tinggi Dalam Meningkatkan Potensi Pariwisata Di Kabupaten Sumenep

Asta Tinggi as one of the heritage of the cultural heritage in Sumenep, is one of the popular religious tourism in the eyes of the local community. Asta Tinggi is the tomb building of the kings of Sumenep and his descendants. The problem in Asta Tinggi is the problem of facilities that are still inadequate to support the needs of tourists, so it takes the development of Asta Tinggi for the success of a tourist destination. This research uses qualitative descriptive methods. The results of this study refer to the focus of research with 3 indicators of success of tourism development according to Yoeti (2008: 96) namely (1) The presence of Attractions and Attractions, this has been done with the existence of tourist attractions carried out by Disparbudpora Kab Sumenep in attracting outside tourists to visit Asta Tinggi. (2) Accessibility, tourists who visit alone can take advantage of gojek to go to Asta Tinggi, and the Sumenep government has also provided 145 guides that are licensed. (3) The existence of facilities, building improvements and fulfillment of facilities that are still felt lacking. Therefore, the conclusion that the Development of Religious Tourism Cultural Heritage asta Tinggi with the promotion of tourism that can be through the Internet media to introduce tourist products, Accessibility is important to be developed as an ease of access for tourists. The advice that can be given is expected to be cooperation between the Sumenep Regency government and the management of Asta Tinggi.

Drag and lift forces acting on linear and irregular agglomerates formed by spherical particles

Nano- and micrometer particles tend to stick together to form agglomerates in the presence of attractions. An accurate calculation of the drag and lift forces on an agglomerate is a key step for predicting the sedimentation rate, the coagulation rate, the diffusion coefficient, and the mobility of the agglomerate. In this work, particle-resolved direct numerical simulation is used to calculate the drag and lift forces acting on linear and irregular agglomerates formed by spherical particles. For linear agglomerates, the drag coefficient CD follows the sine squared function of the incident angle. The ratio between CD of a linear agglomerate and that for a sphere increases with the agglomerate size, and the increasing rate is a function of the Reynolds number and the incident angle. Based on this observation, explicit expressions are proposed for CD of linear agglomerates at two reference incident angles, 60° and 90°, from which CD at any incident angle can be predicted. A new correlation is also proposed to predict the lift coefficient CL for linear agglomerates. The relative errors for the drag and lift correlations are ∼2.3% and ∼4.3%, respectively. The drag coefficient for irregular agglomerates of arbitrary shape is then formulated based on the sphericity and the crosswise sphericity of agglomerates with a relative error of ∼4.0%. Finally, the distribution of the lift coefficient for irregular agglomerates is presented, which is non-Gaussian and strongly depends on the structure. The mean values and the standard deviations of CL can be well correlated with the Reynolds number.

Reflexiones sobre Calentamiento Global y Turismo. Principales riesgos ambientales y regiones turísticas afectadas

The environmental effects related to global warming jeopardize tourism activity and the economic stability of several countries with a marked dependence on activity. Concepts from Social Theory of Risk and the Climate-Tourism Binomial are used, and an analysis is made of the environmental effects of Global Warming, such as the melting of the eternal snows, the rise in sea level, the changes in marine currents and the extreme weather events (hurricanes, floods, rainfall, drought, heat waves) that affect tourism directly and indirectly. Taking into account the World Tourism Organization (UNWTO) regions, emblematic cases were identified whose selection responds to the role of tourism in the economic development of the place or its wealth in terms of tourist attractions. The results allow to account for the modification of climatic situations that contribute tourism, the greater occurrence of natural disasters, the presence of attractions at risk, the destruction of basic infrastructure, among other issues. Therefore, it is important to plan the tourism activity taking into account the threats and risks arising from an increase in atmospheric temperature.

Two-Scale Scenario of Rigidity Percolation of Sticky Particles

In the presence of attraction, the jamming transition of packings of frictionless particles corresponds to the rigidity percolation. When the range of attraction is long, the distribution of the size of rigid clusters, P(s), is continuous and shows a power-law decay. For systems with short-range attractions, however, P(s) appears discontinuous. There is a power-law decay for small cluster sizes, followed by a low probability gap and a peak near the system size. We find that this appearing "discontinuity" does not mean that the transition is discontinuous. In fact, it signifies the coexistence of two distinct length scales, associated with the largest cluster and smaller ones, respectively. The comparison between the largest and second largest clusters indicates that their growth rates with system size are rather different. However, both cluster sizes tend to diverge in the large system size limit, suggesting that the jamming transition of systems with short-range attractions is still continuous. In the framework of the two-scale scenario, we also derive a generalized hyperscaling relation. With robust evidence, our work challenges the former single-scale view of the rigidity percolation.

Motility and chemotaxis of Escherichia coli in medium with attractant and repellent

This study was conducted in order to satisfy the following objectives: (1) To compare the migration bands of Escherichia coli, Bacillus megaterium and Staphylococcus aureus in Sugar, Indole and Motility (SIM) medium + chemotaxis medium (CM), SIM + attractant (glucose), SIM + repellent (alcohol) and SIM only; (2) To observe and compare the swimming behaviour of E. coli under the microscope in the presence of attractant and repellent; and (3) To compare chemotaxis of E. coli in the presence of attractant and repellent by capillary assay. Motility bands were observed in tubes with SIM + CM, SIM + attractant, SIM + repellent and SIM only that were inoculated with E. coli and B. megaterium. However, the motility band in SIM + repellent travelled less far as compared to SIM + CM and SIM + attractant. No motility bands were observed in tubes inoculated with S. aureus. Highest number of colonies (CFU/mL) were observed in capillary tubes dipped in attractant (3.7 x 108), followed by CM (5.2 x 107) and least in repellent (7.6 x 106). Analysis of data showed that log CFU/mL in capillary tubes dipped in attractant (8.55±0.14) was significantly higher as compared to capillary tubes dipped in CM (7.64±0.29) and repellent (6.87±0.14). 
 Keywords: Escherichia coli, motility, chemotaxis, attractant, repellent

An effective method for ecosystem-scale manipulation of bird abundance and species richness.

Manipulation experiments are a cornerstone of ecological research, but can be logistically challenging to execute—particularly when they are intended to isolate the ecological role of large, vagile species, like birds. Despite indirect evidence that birds are influential in many ecosystems, large‐scale, multi‐year bird manipulation experiments are rare. When these studies are conducted, they are typically realized with caged or netted exclosures, an approach that can be expensive, risky for wildlife, and difficult to maintain. In cases where caged exclosures are not appropriate, alternate approaches are needed to allow rigorous empirical studies on the ecological role of birds. Here, we present and validate a method for experimentally increasing the abundance and richness of birds at the scale of entire aquatic ecosystems. Unlike bird exclusion, this approach is experimentally tractable, appealing to land managers, and possible to deploy over large spatial scales. We tested the efficacy of our approach for increasing bird abundance and species richness at 16 central California ponds. Based on bird visitation data obtained by summer camera trapping, our approach significantly increased bird species richness and abundance at manipulated ponds compared to control ponds. Attractant treatments mitigated the negative effects of a major drought on bird species richness and generated a near doubling of bird abundance in the presence of attractants. Treatments had no effect on most mammal species, with the exception of ground squirrels, which increased in abundance in the presence of attractants. These results suggest that attractants are effective in increasing bird abundance and richness. We encourage researchers to consider this approach for experimentally isolating the ecological role of birds in aquatic and open terrestrial ecosystems, especially in cases where cost or logistical constraints preclude the use of caged or netted exclosures.

Lane formation in a driven attractive fluid.

We investigate nonequilibrium lane formation in a generic model of a fluid with attractive interactions, that is, a two-dimensional Lennard-Jones fluid composed of two particle species driven in opposite directions. Performing Brownian dynamics simulations for a wide range of parameters, supplemented by a stability analysis based on dynamical density functional theory, we identify generic features of lane formation in the presence of attraction, including structural properties. In fact, we find a variety of states (as compared to purely repulsive systems), as well as a close relation between laning and long-wavelength instabilities of the homogeneous phase such as demixing and condensation.

Escherichia coli modulates its motor speed on sensing an attractant.

It is well known that Escherichia coli achieves chemotaxis by modulating the bias of the flagellar motor. Recent experiments have shown that the bacteria vary their swimming speeds as well in presence of attractants. However, this increase in the swimming speed in response to the attractants has not been correlated with the increase in the flagellar motor speed. Using flickering dark-field microscopy, we measure the head-rotation speed of a large population of cells to correlate it with the flagellar motor speed. Experiments performed with wild-type and trg-deletion mutant strains suggest that the cells are capable of modulating the flagellar motor speed via mere sensing of a ligand. The motor speed can be further correlated with the swimming speed of the cells and was found to be linear. These results suggest the existence of a hitherto unknown intra-cellular pathway that modulates the flagellar motor speed in response to sensing of chemicals, thereby making chemotaxis more efficient than previously known.

Variation in swimming speed of Escherichia coli in response to attractant.

It is well known that Escherichia coli executes chemotactic motion in response to chemical cues by modulating the flagellar motor bias alone. However, previous studies have reported the possibility of variation in run speed in the presence of attractants although it is unclear whether bacteria can deliberately modulate their swimming speeds in response to environmental cues or if the motor speeds are hardwired. By studying the detailed motion of cells in a uniform concentration of glucose and its non-metabolizable analogue, we show that changing concentrations may be accompanied by variation in the swimming speed. For a fixed run duration, cells exposed to the attractants achieved a higher peak-swimming speed after a tumble compared with that in plain motility buffer. Our experiments using the mutant strain lacking the Trg sensor show no change in swimming speed with varying concentrations of the non-metabolizable analogue, suggesting that sensing may play a role in the observed variation of swimming speed.

Directional Locomotion of C. elegans in the Absence of External Stimuli

Many organisms respond to food deprivation by altering their pattern of movement, often in ways that appear to facilitate dispersal. While the behavior of the nematode C. elegans in the presence of attractants has been characterized, long-range movement in the absence of external stimuli has not been examined in this animal. Here we investigate the movement pattern of individual C. elegans over times of ∼1 hour after removal from food, using two custom imaging set-ups that allow us to track animals on large agar surfaces of 22 cm×22 cm. We find that a sizeable fraction of the observed trajectories display directed motion over tens of minutes. Remarkably, this directional persistence is achieved despite a local orientation memory that decays on the scale of about one minute. Furthermore, we find that such trajectories cannot be accounted for by simple random, isotropic models of animal locomotion. This directional behavior requires sensory neurons, but appears to be independent of known sensory signal-transduction pathways. Our results suggest that long-range directional behavior of C. elegans may not be driven by sensory cues.

Generalizing the Keller–Segel Model: Lyapunov Functionals, Steady State Analysis, and Blow-Up Results for Multi-species Chemotaxis Models in the Presence of Attraction and Repulsion Between Competitive Interacting Species

In this paper we extend the famous Keller–Segel model for the chemotactic movement of motile species to some multi-species chemotaxis equations. The presented multi-species chemotaxis models are more general than those introduced so far and also include some interaction effects that have not been studied before. For example, we consider multi-species chemotaxis models with attraction and repulsion between interacting motile species. For some of the presented new models we give sufficient conditions for the existence of Lyapunov functionals. These new results are related to those of Wolansky (Scent and sensitivity: equilibria and stability of chemotactic systems in the absence of conflicts, preprint, 1998; Eur. J. Appl. Math. 13:641–661, 2002). Furthermore, a linear stability analysis is performed for uniform steady states, and results for the corresponding steady state problems are established. These include existence and nonexistence results for non-constant steady state solutions in some special cases.

On mean coordination and structural heterogeneity in model amorphous solids

We propose a simple route to analytically evaluate the average coordination of model disordered solids with maximally homogeneous distribution of the particles in space. The model yields the average number of contacts (z) as a function of volume fraction (phi) of a hard-sphere connected system and recovers the critical jamming point of hard spheres (z=6 at phi=0.64). Numerical simulations of Lennard-Jones glasses with a varying attraction range are used to investigate the volume fraction dependence of the average coordination in the presence of attraction. It is observed that upon decreasing phi below 0.6, structural heterogeneity is reflected in values of the coordination number which are higher than those predicted by the model for a statistically homogeneous distribution of particles in space due to the attraction-induced local aggregation. Thus the model can be usefully employed as a quantitative reference to assess the degree of structural heterogeneity in glasses in terms of a directly accessible structural parameter such as the mean number of contacts.

Stable topological superconductivity in a family of two-dimensional fermion models

We show that a large class of two-dimensional spinless fermion models exhibit topological superconducting phases characterized by a non-zero Chern number. More specifically, we consider a generic one-band Hamiltonian of spinless fermions that is invariant under both time-reversal, $\mathbb{T}$, and a group of rotations and reflections, $\mathbb{G}$, which is either the dihedral point-symmetry group of an underlying lattice, $\mathbb{G}=D_n$, or the orthogonal group of rotations in continuum, $\mathbb{G}={\rm O}(2)$. Pairing symmetries are classified according to the irreducible representations of $ \mathbb{T} \otimes \mathbb{G}$. We prove a theorem that for any two-dimensional representation of this group, a time-reversal symmetry breaking paired state is energetically favorable. This implies that the ground state of any spinless fermion Hamiltonian in continuum or on a square lattice with a singly-connected Fermi surface is always a topological superconductor in the presence of attraction in at least one channel. Motivated by this discovery, we examine phase diagrams of two specific lattice models with nearest-neighbor hopping and attraction on a square lattice and a triangular lattice. In accordance with the general theorem, the former model exhibits only a topological $(p + ip)$-wave state, while the latter shows a doping-tuned quantum phase transition from such state to a non-topological, but still exotic $f$-wave superconductor.

Effects of shadowing and steering in oblique-incidence metal (100) epitaxial growth

The effects of attraction in oblique-incidence metal (100) epitaxial growth are studied by comparing the results of simulations which include the effects of short-range (SR) and long-range (LR) attraction with results obtained in the absence of attraction. In general, we find that the qualitative dependence of the surface morphology on deposition angle and film thickness, including the existence of a transition from mounds to asymmetric ripples oriented perpendicular to the beam at large deposition angles, as well as a second transition from ripples to rods with (111) facets oriented parallel to the beam at larger deposition angles and film thicknesses, is not altered by the presence of attraction. However, we find that attraction can have two important effects. The first effect, which is a result of steering due to LR attraction and leads to decreased shadowing, leads to decreased anisotropy in the submonolayer regime and can also lead to decreased surface roughness for high-deposition angles and intermediate film thicknesses. The second effect, due to flux focusing, leads to an increase in the surface roughness and feature size and also reduces the critical thickness for ripple and rod formations. This effect also tends to limit the anisotropy in the rod phase for high-deposition angles and film thicknesses. Surprisingly, we also find excellent scaling for the surface roughness as a function of deposition angle and film thickness in the presence of attraction. We also present extensive results for the dependence of the surface morphology on a variety of other parameters including azimuthal angle, growth temperature, deposition flux, and crystal geometry. A comparison between our simulation results and recent experimental results for grazing incidence Cu/Cu(100) growth is also presented.

A free-energy-based stochastic simulation of the tar receptor complex

We recently developed a stochastic-based program that allows individual molecules in a cell signalling pathway to be simulated. This program has now been used to model the Tar complex, a multimeric signalling complex employed by coliform bacteria. This complex acts as a solid-state computational cassette, integrating and disseminating information on the presence of attractants and repellents in the environment of the bacterium. In our model, the Tar complex exists in one of two conformations which differ in the rate at which they generate labile phosphate groups and hence signal to the flagellar motor. Individual inputs to the complex (aspartate binding, methylation at different sites, binding of CheB, CheR and CheY) are represented as binary flags, and each combination of flags confers a different free energy to the two conformations. Binding and catalysis by the complex are performed stochastically according to the complete set of known reactions allowing the swimming performance of the bacterium to be predicted.The assumption of two conformational states together with the use of free energy values allows us to bring together seemingly unrelated experimental parameters. Because of thermodynamic constraints, we find that the binding affinity for aspartate is linked to changes in phosphorylation activity. We estimate the pattern of Tar methylation and effective affinity constant of receptors over a range of aspartate levels. We also obtain evidence that both the methylating and demethylating enzymes must operate exclusively on one or other of the two conformations, and that sites of methylation of the complex are occupied in sequential order rather than independently. Detailed analysis of the response to aspartate reveals several quantitative discrepancies between simulated and experimental data which indicate areas for future research.

"The Fashionable World Displayed": Alcott and Social Power

Fashion, though in strange way, represents all manly virtues. It is virtue gone to seed: it is kind of posthumous honor. It does not often caress great, but children of great: it is hall of Past. --Emerson Self-presentation was source of both pleasure and anxiety for nineteenth-century American women. Louisa May Alcott often felt awkward about how she appeared, especially as she became an increasingly public figure. She knew that she needed to project an image that was bright and comely, but she also knew that, after years of ill health and over-work, such an image would be deceptive. At same time, she was reluctant to risk portrait that would disappoint children.(1) When she and her publisher, Thomas Niles, were searching for suitable images for promotional purposes, Alcott expressed dissatisfaction with all photographs of herself. She eventually sent Niles one (describing it as a sample of pensive invalid) that had been taken at Conly's in Boston in early 1880s (see fig. 1). It is grand and formal portrait of writer, seated with an open volume in hand. She is attired in high Victorian style, in very draped and elaborate afternoon dress. A professionally made garment, it is mainly of silk, with contrasting velvet basque, bustle with tasselled bow, layers of flounces, and an apron-front with frills. effect is very much one of opulence and expense, although dress does not fit very well. And for all that it proclaims its costliness, dress is not actually very stylish. Alcott had chosen to present herself to her public in bustle at precisely wrong moment. By this time bustle had passed height of fashion, and there is no sign of narrower, straighter line that would define mode of 1880s. How appropriate that woman who made career extolling virtues of home sewing should look uncomfortable, should get it slightly wrong, when she tried to conform to image of Boston grande dame of letters.(2) [Figure 1 ILLUSTRATION OMITTED] Alcott had to sell herself to her audience, in that she had to achieve an authoritative and attractive presence. One obvious way of doing this was to avail herself of dress codes of day. But as her diffidence would suggest, she embodied contradictions that did not make such projections comfortable or accurate. In her life and work, she managed several important cultural transformations, notably from rural to metropolitan, from making to buying. She grew up with ideals of genteel modesty, but lived with emergence of conspicuous consumption. Even as she acquired social authority of fame and wealth, she was deeply troubled by what Henry James would call the air of unmitigated publicity.(3) In her most important writing for girls, she used idiom of fashion to express concern over loss of an older sense of intrinsic moral worth. This essay investigates her treatment of power in relation to female self-presentation. I begin with cultural influence of her background, before turning more specifically to her fiction, and to her management of her own professional and social identity. theme throughout is that of class definition, as defined and regulated through women's fashions. In her journal for September 1, 1843, ten-year-old Louisa May Alcott recorded that she had risen at five, taken bath--I love cold water--and spent rest of day in lessons, chores, and exercise. She also mentions being read story called The Judicious Father, which she then summarizes: How rich girl told poor girl not to look over fence at flowers, and was cross to her because she was unhappy. father heard her do it, and made girls change clothes. poor one was glad to do it, and he told her to keep them. But rich one was very sad; for she had to wear old ones week, and after that she was good to shabby girls. …

Free-volume fraction in hard-sphere mixtures and the osmotic spinodal curve.

The sensitivity of the theoretical spinodal curve deduced from the osmotic equilibrium equation for asymmetric hard-sphere mixtures is examined by evaluating the free-volume fraction from three expressions of the excess chemical potential. The conditions for predicting a reduction of the stability domain with increasing asymmetry are discussed. The necessity of modifying this approach in the presence of attractions between the smaller species is underlined. \textcopyright{} 1996 The American Physical Society.

A Model for Transmembrane Signalling by the Aspartate Receptor Based on Random-cassette Mutagenesis and Site-directed Disulphide Cross-linking

Extracellular information is transduced by transmembrane receptors into the inside of the cell across a membrane barrier. To understand the molecular basis of transmembrane signalling, we replaced the transmembrane segment 2 (TM2) of the Escherichia coliaspartate receptor, Tar, with random sequences that are 21 amino acid residues in length and consist of Arg, Gly, Ser, Cys, Val, Leu, Ile and Phe at each position. From this ensemble for recombinant molecules, functional receptors were recovered as clones that could bind aspartate and transmit a signal to the intracellular domain.Restricted average hydrophobicity values were observed for functional transmembrane domains, and support the observation that transmembrane segments typically havehydrophobicity values greater than 1.6. However, non-functional transmembrane domains with greater hydrophobicity than 1.6 indicate that hydrophobicity is not a sole determinant for its function. Fourier transform analysis of the functional TM2 sequences suggest that the transmembrane segment has an α-helical structure with three distinct faces. Cross-linking of the faces to transmembrane segment 1 (TM1) mimics the “locked” signalling phenotypes of the wild-type receptor. The results are consistent with a model in which TM2 rotates in the plane of the lipid bilayer, and the rotation becomes locked at one face of the α-helix in the presence of attractant and at another face in the presence of repellent. This dynamic movement of the transmembrane domain may be a common signalling mechanism of homologous membrane receptor molecule such as the insulin receptor. Random-cassette mutagenesis and disulphde cross-linking provide powerful strategies for examining the structure and function of transmembrane segments.

Olfactory responses of tsetse flies to phenols from buffalo urine

Abstract A comparison was made of the EAG responses of males and females of Glossina morsitans morsitans Westwood, G.austeni Newstead and G.tachinoides, Westwood to various doses of compounds known to be components of ox and buffalo urine fractions which are attractive to tsetse in the field (phenol, 3‐ and 4‐methylphenol, 3‐ and 4‐ethylphenol, 4‐n‐propylphenol, dimethylsulfone). All three species did not respond to dimethylsulfone. The overall responses to the phenolic substances were higher in females than in males in G.m.morsitans and higher in males than in females in G.austeni and G.tachinoides. Response spectra of the species for the phenolic substances suggested that G.m.morsitans and G. austeni were most responsive to 3‐ and 4‐methylphenol and 3‐ethylphenol, whereas G. tachinoides was most sensitive to 3‐ethylphenol and 3‐methylphenol, and only moderately sensitive to 4‐methylphenol.Cross‐adaptation experiments, in which l‐octen‐3‐ol, acetone, 4‐heptanone and 3‐nonanone were also included, revealed that all phenolic compounds stimulated one and the same class of receptors, which differed from the class of receptors activated by l‐octen‐3‐ol. The ketones also had their own receptors. Hence, the flies can obtain information about the presence of attractants by at least three different receptor classes. It was concluded that phenol and any individual alkylphenol found in ox and buffalo urine should be attractive to tsetse flies, provided that stimulus intensity is above threshold and not beyond optimum. One class of receptors may respond more strongly in males than in females, whereas another class is more responsive in females than in males. This may result in a change in sex ratios in catches depending on the odour bait used.

Mutual diffusion of interacting membrane proteins

The generalized Stokes-Einstein equation is used, together with the two-dimensional pressure equation, to analyze mutual diffusion in concentrated membrane systems. These equations can be used to investigate the role that both direct and hydrodynamic interactions play in determining diffusive behavior. Here only direct interactions are explicitly incorporated into the theory at high densities; however, both direct and hydrodynamic interactions are analyzed for some dilute solutions. We look at diffusion in the presence of weak attractions, soft repulsions, and hard-core repulsions. It is found that, at low densities, attractions retard mutual diffusion while repulsions enhance it. Mechanistically, attractions tend to tether particles together and oppose the dissipation of gradients or fluctuations in concentration, while repulsions provide a driving force that pushes particles apart. At higher concentrations, changes in the structure of the fluid enhance mutual diffusion even in the presence of attractions. It is shown that the theoretical description of postelectrophoresis relaxation and fluorescence correlation spectroscopy experiments must be modified if interacting systems are studied. The effects of interactions on mutual diffusion coefficients have probably already been seen in postelectrophoresis relaxation experiments.