Appearance Of Collapse Research Articles

Quantum scheme of dissipative two qubits in a squeezed field: Entanglement and Fisher information

A clear relationship between the quantum version of Fisher information and the bipartite system entanglement has been explored recently. Known existing results for some quantum systems having strongly nonlocal correlations are still limited. In this paper, based on the interaction between a two-qubit and squeezed field, we investigate the correlation between the dynamical behavior of qubit-qubit entanglement and the quantum Fisher information (QFI). We focus on the effect of a number of photon multiplicity, low and high squeezing regime of the field on the dynamics of the QFI and entanglement quantifier. We show how the QFI and entanglement quantifier can be affected by the number of photon multiplicity and squeeze parameter during the time evolution of cases of absence and presence of dissipation effect. Our results exhibit the correlation between the entanglement quantifiers and the QFI with respect to the appearance of collapse and revival phenomena of the atomic inversion.

Stability criterion for solitons of the Zakharov–Kuznetsov-type equations

Early results concerning the linear stability of the solitons in equation of the KDV-type [1] are generalized to solitons describing by the Zakharov–Kuznetsov-type equation. The linear stability criterion for ground solitons in the Vakhitov–Kolokolov form is derived for such equations with arbitrary nonlinearity. For the power nonlinearity the instability criterion coincides with the condition of the Hamiltonian unboundedness from below. The latter represents the main feature for appearance of collapse in such systems.

Deciphering the Enigma of Wave-Particle Duality

<p>A satisfactory explanation of the confounding wave-particle duality of matter is presented in terms of the reality of the wave nature of a particle. In this view, a quantum particle is an objectively real wave packet consisting of irregular disturbances of underlying quantum fields. It travels holistically as a unit and thereby acts as a particle. Only the totality of the entire wave packet at any instance embodies all the conserved quantities, for example the energy-momentum, rest mass, and charge of the particle, and as such must be acquired all at once during detection. On this basis, many of the bizarre behaviors observed in the quantum domain, such as wave function collapse, the limitation of prediction to only a probability rather than an actuality, the apparent simultaneous existence of a particle in more than one place, and the inherent uncertainty can be reasonably comprehended. The necessity of acquiring the wave function in its entirety for detection, as evinced by the appearance of collapse of the wave function, supports the paradigm of reality of the wave function described here.</p><p>Quanta 2016; 5: 93–100.</p>

Electromagnetic envelope solitary waves with transverse perturbation in a plasma

The system of fluid-Maxwell equations governing the two-dimensional dynamics of electromagnetic waves in a plasma is analyzed by means of multiple scale perturbation method. It is shown that the evolution of the amplitude of wave field is governed by a two-dimensional nonlinear Schrödinger equation. The stability of bright envelope solitons is studied using the variational method. It is found that the development of transverse periodic perturbations on bright solitons is faster for a plasma with near critical density. Dynamics of electromagnetic bright solitons is investigated in the long-wave approximation. Our model predicts the appearance of collapse of electromagnetic waves in plasmas and describes the collapse dynamics at initial stages.

Phases 1–3 Clinical Trials Using Adult Stem Cells in Osteonecrosis and Nonunion Fractures

Nonunion fractures and aseptic bone necrosis are two pathological conditions having some impairment of the cellular part of the repair: a reduction of MSC and of the osteoblastic activation. Both are good candidates for cell-based therapies using stem cells. We made a review of the published human trials. Only autologous bone marrow aspirate implantation was until now used. In Nonunion, a direct injection—15 to 150 ml—was made in 4 case series studies. In another, the bone marrow aspirate was concentrated before injection. The results were good. In bone necrosis, only one level 1 study was published. The results at 24 months were positive in terms of reduction of the necrosis and appearance of collapse. In 3 case series studies, a treatment with concentrated bone marrow aspirates was deemed useful with good results in 76 to 96%. These results are interesting but need confirmation by controlled studies.

Freeze-Dry Microscopy of Protein/Sugar Mixtures: Drying Behavior, Interpretation of Collapse Temperatures and a Comparison to Corresponding Glass Transition Data

The purpose of this study is to investigate the change in collapse appearance and temperature of protein/sugar mixtures as a function of nucleation temperature (T(n)), sublimation velocity (V(sub)) and the sugar/protein mole ratio when performing freeze-dry microscopy experiments. BSA and HSA were used as sample proteins and mixed with either sucrose or trehalose. Differential scanning calorimetry was used to determine the corresponding glass transition temperatures (T'g). To allow a more representative comparison between these analytical methods, a collapse midpoint temperature (T(c-50)) was introduced. While there was no distinct correlation between T(n) and the onset of collapse (T(oc)) for either mixture, V(sub) was found to correlate with the measured collapse temperature which is important for comparability of experiments. Furthermore, V(sub) could be used to qualitatively investigate the product resistance to water vapor flow. A dramatic change in the appearance of collapse was found for high sugar/protein mole ratios (> or =362:1) which needs to be considered to avoid a misinterpretation of T(oc) data. At low protein concentrations midpoint T'g data showed good agreement with T(oc) values but were found significantly lower at higher protein concentrations. Application of the Gordon-Taylor equation failed to predict the critical temperature for any of the protein/sugar mixtures studied.

Revivals of quantum wave packets in graphene

We investigate the propagation of wave packets on graphene in a perpendicular magnetic field and the appearance of collapses and revivals in the time evolution of an initially localized wave packet. The wave-packet evolution in graphene differs drastically from the one in an electron gas and shows a rich revival structure similar to the dynamics of highly excited Rydberg states. We present a novel numerical wave-packet propagation scheme in order to solve the effective single-particle Dirac–Hamiltonian of graphene and show how the collapse and revival dynamics is affected by the presence of disorder. Our effective numerical method is of general interest for the solution of the Dirac equation in the presence of potentials and magnetic fields.

Influência do envelhecimento acelerado na anatomia da testa de sementes de soja, cv. Monsoy 8400

Durante o processo de envelhecimento, as sementes sofrem alterações degenerativas que influenciam o seu potencial fisiológico. Entre estas alterações podem estar as modificações anatômicas nas camadas celulares da testa da semente. Objetivou-se, com este trabalho, verificar a relação entre a anatomia da testa de sementes de soja, cultivar Monsoy 8400 e a germinação, após o envelhecimento acelerado, pelo fato da testa apresentar um papel fundamental na conservação do potencial fisiológico das sementes. As sementes foram envelhecidas a 42ºC e 100% UR do ar por períodos de zero, 24, 48, 72 e 96 horas. Avaliaram-se os teores de água e a germinação, posteriormente à secagem, seções transversais da testa de 10 sementes de cada tratamento foram eletromicrografadas, com microscópio eletrônico de varredura,,observando-se as camadas das células paliçádicas, ampulhetas e parenquimáticas A germinação declinou com o aumento dos períodos de envelhecimento. Houve redução da espessura das camadas da testa nos períodos de 48, 72 e 96 horas deste processo. Observou-se que, principalmente, para os períodos de envelhecimento de 72 e 96 horas, que as células da camada hipodérmica apresentaram um aspecto de colapso, sendo este acentuado para o período de 96 horas. A redução da espessura das camadas sugere a ocorrência de um colapso das células que compõem tais camadas, sendo um fator causador da redução do potencial germinativo.

Radiographic appearance of lobar collapse

The changes to the chest radiograph that may be expected in lobar collapse are described: changes in density; changes in position; and alterations in the appearances of borders. Pure lobar collapse is rare and the features described only represent a guide. The appearances of collapse of each lobe are described in detail. Examples of radiographs and line drawings describing the movements of the fissures are included. There is a brief comment on subsegmental collapse.

Collapses and revivals of exciton emission in a semiconductor microcavity: Detuning and phase-space filling effects

We investigate exciton emission of quantum well embedded in a semiconductor microcavity. The analytical expressions of the light intensity for the cases of excitonic number state and coherent state are presented by using secular approximation. Our results show that the effective exciton-exciton interaction leads to the appearance of collapse and revival of the light intensity. The revival time is twice compared the coherent state case with that of the number state. The dissipation of the exciton-polariton lowers the revival amplitude but does not alter the revival time. The influences of the detuning and the phase-space filling are studied. We find that the effect of the higher-order exciton-photon interaction may be removed by adjusting the detuning.

Interpolation from number states to chaotic states of the electromagnetic field

We introduce new two-parameter states of the quantized radiation field interpolating from number states to chaotic states. Instead of dealing with pure states, we consider truncated mixtures of number states - number-chaotic states (NCS) - which reduce to number and chaotic (thermal) states in two well-defined limits. We study the statistical and squeezing properties of such states and show that there is a value of the chaoticity parameter at which a transition from sub- to super-Poissonian characteristics occurs. Analysing the atomic population inversion in the Jaynes-Cummings model for these NCSs, we demonstrate the appearance of collapses and revivals as is increased. Their phase space representations are studied emphasizing the changes as the parameters are varied and we discuss the nonclassical depth.

高度骨欠損を伴った人工股関節臼蓋再置換術の経験

We experienced two cases of revision total hip arthoplasty (THA) with severe acetablar deficiencies, which we categorized as Type III according to the classification of the American Academy of Orthopaedic Surgeons (A. A. O. S). In the both cases, we reconstructed the acetablar defects with auto and allograft, using the KT-plate. The pallet of the KT-plate could not reach the host bone directly because of extensive bone loss of the acetablum. Accordingly, we grafted the autogenous tri-cortical iliac bone in the gap between the host bone and pallet of the KT-plate, and also morselized allograft in the remaining cavitary defects. At final examination 10 and 11 months after operation, both patients were relieved from hip joint pain and their walking ability had improved. There was no appearance of collapse of the grafted bone nor evidence of loosening up to the present.

Collapse-revival Phenomenon in the Process ofk-photon Down Conversion with Superpositions of Number States

Abstract We calculate numerically the time evolution of the mean photon number in the process of k-photon down conversion process with quantized pump. The pump mode was supposed to be initially in a superposition of number states and the down converted mode in a number state. We analysed in some detail the influence of the initial field statistics of the pump mode as well as the presence of non-vacuum number states in the down converted mode on the appearance of collapses and revivals.

Quantum properties of field modes in trilinear optical processes.

We consider a trilinear Hamiltonian in boson operators describing various physical processes such as frequency conversion, Raman or Brillouin scattering, or the interaction of N two-level atoms with a single-mode radiation field. Due to the fact that two independent integrals of motion can be found, the solution of the dynamics of the system is reduced to the diagonalization of a finite matrix (as was already shown by Walls and Barakat [Phys. Rev. A 1, 446 (1970)]). Performing a numerical diagonalization, we analyze the statistical properties of the field modes (sub-Poissonian statistics, anticorrelation, squeezing). We also pay attention to the appearance of collapses and revivals in the mean photon number of the modes. The relation of this model to the model of two coupled modes with an intensity-dependent coupling constant is pointed out.

Computed tomography of lobar collapse: 1. Endobronchial obstruction.

The computed tomographic (CT) appearance of lobar collapse has yet to be defined. In an attempt to determine the characteristic appearance of collapse 95 cases were reviewed retrospectively in a wide variety of clinical settings over a 3 year period ending January 1983. In this report 38 cases of lobar collapse secondary to endobronchial occlusion are analyzed; the appearance of collapse without endobronchial obstruction forms the basis of a subsequent report. Computed tomography was accurate in determining the site of bronchial occlusion in all cases. In 36 of 38 cases collapse was caused by endobronchial tumors, including bronchogenic carcinoma, bronchial carcinoids, endobronchial metastases, and lymphoma. Differentiation between these tumors was not feasible with CT. Most cases of collapse were caused by central tumor. In those cases in which a bolus of contrast material was used differentiation between tumor mass and collapsed pulmonary parenchyma was possible. Two of 38 cases were found to have benign bronchial occlusion. In one case a mucous plug obstructing the left lower lobe bronchus was accurately defined. In another case a bronchial stricture occluded the right lower lobe bronchus. This represented the only false positive case in this series. It is concluded that CT is an accurate means for establishing the diagnosis of endobronchial obstruction. In most cases the diagnosis of neoplasia was possible, provided a bolus of contrast material was used to define tumor mass. The potential role of CT in evaluating patients with lobar collapse is discussed.

Computed tomography of lobar collapse: 2. Collapse in the absence of endobronchial obstruction.

The computed tomographic appearance of collapse without endobronchial obstruction is reviewed. These 57 cases were classified by the etiology of collapse. The largest group consisted of 29 patients with passive atelectasis, i.e., collapse secondary to fluid, air, or both in the pleural space. Twenty-three of 29 proved secondary to malignant pleural disease. Computed tomography accurately predicted a malignant etiology in 22 of 23 cases. The second largest group of patients had lobar collapse secondary to cicatrization from chronic inflammation. In all cases the underlying etiology was tuberculosis. Radiation caused adhesive atelectasis in six patients secondary to a lack of production of surfactant. In each case a sharp line of demarcation could be defined between normal and abnormal collapsed pulmonary parenchyma. Three cases of unchecked tumor growth caused a peripheral form of collapse (replacement atelectasis). This form of collapse was characterized by an absence of endobronchial obstruction and extensive tumor not delineated by the normal boundaries of the pulmonary lobes.

The nature of reaction wood. IV. Variations in cell wall organization of tension wood fibres

The cell wall organization, the cell wall texture, and the degree of lignification of tension wood fibres have been investigated in a wide variety of temperate and tropical species. Following earlier work describing the cell wall structure of tension wood fibres, two additional types of cell wall organization have been observed. In one of these, the inner thick "gelatinous" layer which is typical of tension wood fibres exists in addition to the normal three-layered structure of the secondary wall; in the other only the outer layer of the secondary wall and the thick gelatinous layer are present. In all the tension wood examined the micellar orientation in the inner gelatinous layer has been shown to be nearly axial and the cellulose of this layer found to be in a highly crystalline state. A general argument is presented as to the meaning of differences in the degree, of crystallinity of cellulose. The high degree of crystallinity of cellulose in tension wood as compared with normal wood is attributed to a greater degree of lateral order in the crystalline regions of tension wood, whereas the paracrystalline phase is similar in both cases. The degree of lignification in tension wood fibres has been shown to be extremely variable. However, where the degree of tension wood development is marked as revealed by the thickness of the gelatinous layer the lack of lignification is also most marked. Severity of tension wood formation and lack of lignification have also been correlated with the incidence of irreversible collapse in tension wood. Such collapse can occur even when no whole fibres are present, e.g. in thin cross sections. Microscopic examination of collapsed samples of tension wood has led to the conclusion that the appearance of collapse in specimens containing tendon wood can often be attributed in part to excessive shrinkage associated with the development of fissures between cells, although true collapse does also occur. Possible explanations of the irreversible shrinkage and collapse of tension wood fibres are advanced.

Patterns of lobar collapse as observed radiographically.

THE RECOGNITION of lobar collapse is the responsibility of the radiologist, but his obligations do not cease with the diagnosis. He must convince the referring physician of its presence, a frequently difficult task. To do this, he must be able to simplify the intricacies and analyze the pitfalls of the diagnosis for the benefit of his colleagues. Robbins and Hale in a very important series of papers have presented a careful and thoughtful analysis of the radiologic findings in lobar and segmental collapse of the lungs. We have accepted their views on the subject as valid and highly significant, but we frequently have felt the need for further elaboration and more detail, especially from a teaching standpoint. For this purpose, we have reviewed our available material, selections from which will illustrate the typical appearance of lobar collapse, as well as variations from the usual pattern. As a result of this study, we will present in diagrammatic form (Figs. 1, 6, 11, 16) the probable sequence of events which occur in a lobe undergoing collapse. This study also will reveal the underlying unity of what seems to be a varied roentgen picture and will explain the reasons for the typical and atypical roentgen findings. The terms “collapse,” “atelectasis,” and “septum” are employed according to the definitions of Robbins and Hale. “Collapse” indicates loss of volume, while “atelectasis” signifies airlessness in addition. In this study we have been particularly interested in the roentgen appearance of the lobe in various stages of collapse and the concurrent changes in the position of the associated interlobar septa as seen in the lateral view, so that greatest emphasis has been placed on these aspects of the problem. Other roentgen findings seen in collapse of a lobe, such as change in position and size of the pulmonary root, the groupings of the pulmonary markings, the size of the hemithorax and position of the diaphragm, while extremely important, have been well described and will not primarily concern us in this report. General Considerations In order to understand the mechanism of lobar collapse and the consequent roentgen appearance, it is of primary importance to consider the lung and its major subdivisions as semi-rigid rather than purely elastic structures. Except for the alveoli, collapsed pulmonary tissue cannot be likened to a deflated balloon, although this comparison is frequently made. A number of factors account for this. The cartilaginous content of the bronchial walls causes them to resist distortion. The angle at which the bronchus leaves its parent structure, its length, and the amount of cartilage in its wall in part determine the magnitude and direction of movement, and hence the eventual radiographic appearance of a collapsed lobe.

Miliary carcinomatosis of the lungs: Report of a case simulating miliary tuberculosis

Summary 1. The subject of miliary carcinomatosis of the lungs is briefly reviewed with notes on the pathology and clinical features of the cases reported in the literature. 2. It is stressed that diagnosis is frequently difficult and often made only late or on the autopsy table. 3. A case is described in a male patient aged 25 years which so closely simulated miliary tuberculosis that it was diagnosed as such and treated with streptomycin. 4. The site of the primary growth appeared to be the right lung. 5. It is stressed that the signs and X-ray appearance of collapse of the lung should make bronchoscopy an essential step in the establishment of a diagnosis, but in this particular case the investigation would probably have failed to reveal any abnormality. 6. It is suggested that miliary carcinomatosis of the lungs may so closely resemble miliary tuberculosis that differentiation on clinical grounds can be virtually impossible.

The Roentgen Appearance of Lobar and Segmental Collapse of the Lung

Collapse of a single lobe of the lung is most frequently misinterpreted when it occurs in one of the upper lobes. It is confused with a localized area of consolidation, a mediastinal tumor, or an aortic aneurysm, and in some instances, especially in the presence of a long standing fibrotic process without apparent atelectasis, it may be completely overlooked. Its occurrence is relatively infrequent as compared with collapse in the lower lobes or the middle lobe, but it is common enough to warrant greater emphasis than has been given it in the literature. In the group of 600 cases forming the basis of this study,2 the upper lobes were involved in 95, or 16 per cent. Certain roentgenologic signs which characterize collapse of an upper lobe and which, if recognized, will lessen some of the confusion regarding its diagnosis will be described. It has been noted in earlier papers of this series that in the majority of instances it is possible with satisfactory technic to demonstrate the septa which bound the individual lobes of the lung. These lines, which roentgenologically can be thought of as partitions between the various lobes, are seen to best advantage on the lateral roentgenogram. The routine postero-anterior view is depended upon to show any abnormal shadow of increased density, the presence and degree of emphysema in the adjoining lobes, the position of the trachea and upper mediastinum, the relative planes in which the hili are located, and usually the minor septum. The upper lobes lie superiorly and anteriorly in the chest; that is, the left upper lobe is anterior to the major septum along its entire course, while the right upper lobe lies above the minor septum and anterior to that portion of the major septum above its junction with the minor septum. The location of a normal lobe in relation to the septa is stressed repeatedly because of its diagnostic significance. By the recognition of the individual lobes and the septa which bound them, it becomes more nearly possible to demonstrate on a roentgenogram the precise unit of a lung that is projected on a given area. In this way, it is possible roentgenologically to recognize the presence of a pulmonary unit which is not assuming its full share in aeration even before an abnormal shadow of increased density, indicating the nature of the disease process (or in some instances its result) can be detected. The significance of this concept is similar to that of a break in the peristaltic wave in the stomach pointing to a neoplasm or ulcer crater which otherwise might be overlooked. With a few exceptions, the roentgen appearance of collapse of an upper lobe or of its segments is essentially the same regardless of the side involved. On the left, the lingula of the upper lobe occupies a position in the chest similar to that of the middle lobe on the right, but it derives its bronchial supply from the left upper lobe bronchus and is not separated from the remainder of the upper lobe by a fissure.