Finite-size effects in addition and chipping processes.

We investigate analytically and numerically a system of clusters evolving via collisions with clusters of minimal mass (monomers). Each collision either leads to the addition of the monomer to the cluster or the chipping of a monomer from the cluster, and emerging behaviors depend on which of the two processes is more probable. If addition prevails, monomers disappear in a time that scales as lnN with the total mass N≫1, and the system reaches a jammed state. When chipping prevails, the system remains in a quasistationary state for a time that scales exponentially with N, but eventually, a giant fluctuation leads to the disappearance of monomers. In the marginal case, monomers disappear in a time that scales linearly with N, and the final supercluster state is a peculiar jammed state; i.e., it is not extensive.

Hopf bifurcation in addition-shattering kinetics.

In aggregation-fragmentation processes, a steady state is usually reached. This indicates the existence of an attractive fixed point in the underlying infinite system of coupled ordinary differential equations. The next simplest possibility is an asymptotically periodic motion. Never-ending oscillations have not been rigorously established so far, although oscillations have been recently numerically detected in a few systems. For a class of addition-shattering processes, we provide convincing numerical evidence for never-ending oscillations in a certain region U of the parameter space. The processes which we investigate admit a fixed point that becomes unstable when parameters belong to U and never-ending oscillations effectively emerge through a Hopf bifurcation.

Steady oscillations in aggregation-fragmentation processes.

We report surprising steady oscillations in aggregation-fragmentation processes. Oscillating solutions are observed for the class of aggregation kernels K_{i,j}=i^{ν}j^{µ}+j^{ν}i^{µ} homogeneous in masses i and j of merging clusters and fragmentation kernels, F_{ij}=λK_{ij}, with parameter λ quantifying the intensity of the disruptive impacts. We assume a complete decomposition (shattering) of colliding partners into monomers. We show that an assumption of a steady-state distribution of cluster sizes, compatible with governing equations, yields a power law with an exponential cutoff. This prediction agrees with simulation results when θ≡ν-µ<1. For θ=ν-µ>1, however, the densities exhibit an oscillatory behavior. While these oscillations decay for not very small λ, they become steady if θ is close to 2 and λ is very small. Simulation results lead to a conjecture that for θ<1 the system has a stable fixed point, corresponding to the steady-state density distribution, while for any θ>1 there exists a critical value λ_{c}, such that for λ<λ_{c}, the system has an attracting limit cycle. This is rather striking for a closed system of Smoluchowski-like equations, lacking any sinks and sources of mass.

Oscillations in Aggregation-Shattering Processes.

We observe never-ending oscillations in systems undergoing collision-controlled aggregation and shattering. Specifically, we investigate aggregation-shattering processes with aggregation kernels K_{i,j}=(i/j)^{a}+(j/i)^{a} and shattering kernels F_{i,j}=λK_{i,j}, where i and j are cluster sizes, and parameter λ quantifies the strength of shattering. When 0≤a<1/2, there are no oscillations, and the system monotonically approaches a steady state for all values of λ; in this region, we obtain an analytical solution for the stationary cluster size distribution. Numerical solutions of the rate equations show that oscillations emerge in the 1/2

Diffusion mechanism of exchange bias formation in permalloy-manganese nanostructures at thermo-magnetic treatment.

A mechanism of unidirectional exchange anisotropy formation at thermo-magnetic treatment of permalloy-manganese bilayers has been studied. A shift of hysteresis loops appears at annealing beginning from 230 degrees C. The maximal exchange field of 155 Oe is reached after the 250 degrees C annealing for 2 h. As demonstrated by transmission electron microscopy, the exchange bias and the coercivity growth result from an ordered anti-ferromagnetic NiFeMn phase formation due to the diffusion interaction of permalloy and manganese at annealing.

[Treatment of patients with purulent diseases of the hand, the typical mistakes and complications].

In a review of the literature addresses the causes, characteristics of the purulent process of the hand, the questions of treatment of purulent diseases of the hand, methods of anesthesia and rehabilitation of the patients with this pathology. The typical mistakes in the delivery of health care of this category of patients.

[Independent medical processing enterprises as innovative organizational model for market of medical services].

In Russia, current stage of health care development is characterized by occurrence of various problems. Most of them are related to cooperation between participators of market of medical services. Different options are proposed to resolve cooperation problems embedded into medical services market with emphasis on development of ultimately different medical processing enterprise with brand-new organizational and functional structure. Its functioning is based on process management logistics. The company broad professional experience allows to implement above-mentioned managerial structure and make it function as well as claims positive perspectives of described option.

[Infectious endocarditis as a surgical problem in Russia]. / Infektsionnyi éndokardit kak khirurgicheskaia problema v Rossii.

Infectious endocarditis (IE) is mainly a surgical problem and requires an integration of efforts of specialists of different fields for its treatment. Successful treatment of this severe disease is to be based on the early diagnosis and early operation. So IE should be estimated as a surgical pathology and this nosological form must be included in all manuals on general surgery and studying infectious endocarditis must be included in the programs of training doctors at surgical series of lectures. Such interpretation of this question will change doctors' mentality and will lead to the earliest admission of the patient with this pathology to specialized cardiosurgical hospital and will allow to avoid severe disabling complications of IE, to increase the number of valve-saving operations and to improve prognosis in the treatment of this disease.

[Prevention of prosthetic heart valve infection]. / Profilaktika infitsirovaniia iskusstvennykh klapanov, implantirovannykh v serdtse.

Fourty patients with primary and secondary infective endocarditis of the native heart valves as well as patients with rheumatic heart diseases not complicated by infective endocarditis were operated upon in the clinic from 1996 till 1998. The prosthetic heart valves in which the tissue cuff was sutures by blanket suture along the perimeter with a silver thread were implanted to 25 patients. In the other 15 patients (a control group) prosthetics were made using unchanged construction of the prosthesis (without the silver thread). Patients with valve prostheses sutured with the silver thread had smooth postoperative period. They had no prosthetic endocarditis either at the early or at late postoperative periods. In 3 patients of the control group infective endocarditis of the valve prosthesis developed at different periods after operation. All of them were reoperated. The authors consider that defense of the tissue cuff of the prosthetic valve with the silver thread allows risk of the development of prosthetic endocarditis to be substantially reduced. In the cases described it was completely avoided.

[The early diagnosis of postoperative infectious complications in heart surgery patients]. / Ranniaia diagnostika posleoperatsionnykh infekstionnykh oslozhnenii u kardiokhirurgicheskikh bol'nykh.

Great surgical aggression in operations on the heart and resulting immunodeficiency create prerequisites for the appearance and grave course of infectious complications. The authors have analyzed results of operative treatment of 100 patients with acquired valvular diseases. It has been established that low parameters of the resistance index of organism (RIO) before operation can be estimated as an unfavourable prognostic sign of the development of infectious complications. The RIO dynamics at the postoperative period in many aspects reflects the character of its course. RIO and the indices of the adaptation reaction show the degree of intoxication, make the clinical estimation objective, allow the assessment of efficiency of therapy and correction of medical prescriptions.

[Hospital infection and some aspects of its immunoprophylaxis]. / Gospital'naia infektsiia i nekotorye aspekty ee immunoprofilaktiki.

The review deals with the causes and main agents of the hospital infection occurring in surgical units. Special attention is given to the formation of the hospital isolate of the agent. A method of prevention of postoperative infective complications by vaccines prepared of these particular isolated has been proposed.

[The organization of the donation of autologous blood and its components in cardiac surgery]. / Organizatsiia autodonorstva krovi i ee komponentov v kardiokhirurgii.

The article analyzes an experience with the organization of autodonation of blood and its components in surgical treatment of 305 patients with congenital and acquired defects and ischemic heart disease. Methods of plasmacytapheresis and cryopreservation used at the terms from 3 days to 12 months before operation allowed storage of the autologous components of blood in 41.2% of the patients having indications for autodonation. In 29.1% of the observations the autotransfusion media were reserved under the outpatient clinic conditions which resulted in shorter terms of treatment at the hospital. The number of unfavorable reactions during the donation in patients did not exceed analogous parameters in regular donors. Autohemotransfusions 3-5 times reduced the volume of transfusions of the allogenic blood components and they were completely avoided in 20.1% of the patients.

[Calcinosis and its meaning in heart surgery]. / Kal'tsinoz i ego znachenie v kardiokhirurgii.

The paper presents the analysis of calcinosis frequency and expressivity of calcinosis revealed during surgical treatment of 598 patients with acquired heart defect. In operative interventions under EKG conditions calcinosis was observed in 25% cases, and in performance of closed mitral commissurotomy in 36.7%. Retrospective analysis of special features of the illness course in 346 patients with rheumatic mitral defect accompanied by predominant stenosis in dependence on presence and degree of stenosis expessivity. The role of calcinous conglomerates as chronic intracardiac infection reservoirs is noted.

[The surgery of functional myocardial incompetence: the status of the problem and the outlook for its development]. / Khirurgiia funktsional'noi nesostoiatel'nosti miokarda: sostoianie problemy i perspektivy ee razvitiia.

The literature data are analyzed concerned with the correction of disturbances of the myocardium contraction function by a transplantation of the donor's heart, implantation of an artificial heart and cardiomyoplasty. The implantation of cardiomyocytes is considered to be a promising method.