In treating cases of malignancy, the use of chemotherapy carries a high risk of lower respiratory tract infections, especially fungal pneumonopathy. This complication is a major cause of mortality and is often difficult to diagnose because of non-specific clinical or radiological changes, but the early recognition of invasive fungal disease is imperative. CT is an important non-invasive method for the detection and evaluation of opportunistic fungal infections. In these patients an improved survival rate can be achieved when early detection by CT leads to the prompt institution of high-dose antifungal therapy. We illustrate the spectrum of CT findings of invasive pulmonary aspergillosis encountered in children with cancer. These patients had previously been treated with high-dose chemotherapy with or without bone marrow rescue, and underwent radiological examinations because of clinical evidence of pneumonopathy. Representative cases demonstrate the clinical applications of CT in the evaluation and management of invasive fungal disease.

Cranial CT and/or MRI imaging of 8 patients with mucopolysaccharidosis (MPS) was retrospectively evaluated. Two patients had MPS IH, 1 had MPS IS, 1 had MPS IVA and 4 had MPS IV. CT and MRI showed thickening of dura mater at the cranio-cervical junction, causing narrowing of the subarachnoid space, in all the patients examined. Spinal cord compression was detected in 4 patients. Other findings were: white matter alterations, mild to severe hydrocephalus, skull dysplasia and odontoid dysplasia. White matter alterations were evident as large areas and as multiple dispersed spots of prolonged T1 and T2 value. Reduced gray/white matter contrast was demonstrated on T2-weighted MRI images. It is important to examine the cranio-cervical junction carefully for thickening of dura mater in all patients with mucopolysaccharidosis examined by CT or MRI, because of the generally progressive clinical course of MPS. In patients with symptomatic cord compression, surgical intervention should be considered.

The experimental fission times are analyzed for excited nuclei produced in the 28Si + natPt reaction. Experimental lifetimes obtained by the crystal-blocking technique range between 10−17 and 10−18 s at bombarding energies between 140 and 170 MeV, respectively. Experimental data are analyzed within the statistical theory of nuclear reactions and the double-humped-fission-barrier model with allowance for preequilibrium processes and the nuclear-dissipation phenomenon. It is shown that fission barriers retain their double-humped structure for nuclear temperatures up to about 1.7–1.8 MeV and that the lifetimes of excited strongly deformed states in the second potential well contribute substantially to the observed delay times in the fission decay channel.

The role of the entrance channel in fusion-fission reactions was studied by the theoretical analysis of the experimental evaporation residue excitation functions for reactions leading to the same compound nucleus. The evaporation residues cross sections for xn-channels were calculated in the frame of the combined dinuclear system concept and advanced statistical model. The revealed differences between experimental data on the evaporation residues in the ^{40}Ar+^{176}Hf, ^{86}Kr + ^{130}Xe and ^{124}Sn + ^{92}Zr reactions leading to the ^{216}Th^* compound nucleus are explained by the different spin distributions of compound nuclei which are formed. It is shown that the intrinsic fusion barrier B^*_{fus} and size of potential well are different for every entrance channel.

The experimental fission times are analyzed for excited nuclei produced in the Si-28 + Pt-nat reaction. Experimental lifetimes obtained by the crystal-blocking technique range between 10(-17) and 10(-18) s at bombarding energies between 140 and 170 MeV, respectively. Experimental data are analyzed within the statistical theory of nuclear reactions and the double-humped-fission-barrier model with allowance for preequilibrium processes and the nuclear-dissipation phenomenon. It is shown that fission barriers retain their double-humped structure for nuclear temperatures up to about 1.7-1.8 MeV and that the lifetimes of excited strongly deformed states in the second potential well contribute substantially to the observed delay times in the fission decay channel. (C) 2002 MAIK "Nauka/Interperiodica".

The crystal blocking technique has been used to measure delay times in the fission channel for excited nuclei produced in the 28 Si+ n a t Pt reaction. Experimental results range from 10 -17 to 10 -18 s at bombarding energies from 140 to 170 MeV. It is shown that fission barriers keep their double-humped structure for nuclear temperature up to 1.7–1.8 MeV, and that the lifetimes of excited states in the second potential well contribute essentially to the observed delay times in the fission channel.

We consider the Ca-48+ U-238 and Ca-48+ Pu-242,Pu-244 reactions that lead to the Z=112 and 114 superheavy elements respectively. The fusion-fission reaction mechanism leading to the massive nucleus formation is studied. By using the dinuclear system-concept of the two interacting nuclei, we calculate the quasifission-fusion competition in entrance channel and the fission-evaporation competition along the de-excitation cascade of the compound nucleus. For the Z=112 production it is possible to compare the result obtained by the Zn-70+ Pb-208 cold fusion reaction (asymmetric reaction) with the result obtained by the Ca-48+ U-238 hot fusion reaction (more asymmetric reaction). We calculate the Gamma (n)/Gamma (tot) ratio at each step of the de-excitation cascade and we show a systematics of this ratio fat first step of the cascade) for many reactions that lead to nuclei with Z=102 - 114. We also find that the ratio between the evaporation residue cross section and the fusion cross section is mainly dependent on the E*/B-fis ratio for the studied reactions.

Nuclear-rainbow effects in elastic and inelastic scattering and transfer reactions by the He-3 + C-12 interaction at E(He-3) = 98 MeV are observed, analyzing the angular distributions of the He-3, H-2 and He-4 particles. The data are analyzed by a near/far-side formalism using Fuller's model. We also observe the different characteristics of the rainbow effects and of the shape of the angular distributions for various reaction mechanisms.

Nuclear-rainbow effects in elastic and inelastic scattering and transfer reactions by the3He+12C interaction atE(3He)=98 MeV are observed, analyzing the angular distributions of the3He,2H and4He particles. The data are analyzed by a near/far-side formalism using Fuller's model. We also observe the different characteristics of the rainbow effects and of the shape of the angular distributions for various reaction mechanisms.

We retrospectively reviewed T1-weighted MR images of 381 patients aged from 7 days to 24 years to evaluate the bone marrow change in thoracic wall and shoulder, pelvis and proximal femur and upper and lower extremities. The patients included in the study were without history of bone marrow disease, A grade of from 1 to 4 was assigned to the marrow signal intensity of the examined anatomic segments, The signal intensity of all anatomic segments was as low as or lower than that of muscle in all patients younger than 2 months, reflecting underlying hematopoietic marrow, The first segments to become hyperintense were the epiphyseal/round bone ossification centers, followed by the phalanges, diaphysis, flat bones and metaphysis. Marrow signal intensity increased in all regions with age, While in the epiphyseal/round bones and diaphysis bone marrow shows a diffuse and homogeneous increased signal intensity with age, in the sternum, ribs, scapulae, posterior ilium and metaphysis varying percentages of intermediate signal intensity are maintained. An orderly progression of red to yellow marrow was established.

In the present paper a new experimental method to measure nuclear reaction time in the 10−15–10−10 s region is presented. Measurements of the lifetimes of low-lying and long-lived states of 19F and 20Ne decaying via α-channel were carried out with the aim of checking the feasibility of the method. The results obtained in this way are compared with the lifetimes known from different techniques.