What's the signification of nuclear vacuoles in human sperm?

The aim of this study was to determine the extent of DNA fragmentation and the presence of single/denatured or double stranded of DNA in sperm with large nuclear vacuoles (LNV) selected by high-magnification. A total of 30 patients had fresh semen samples prepared by discontinuous concentration gradient. Sperm with normal nucleus (NN) and LNV were selected at 8400x magnification and placed in different slides. DNA fragmentation was determined by TUNEL assay. Denatured and double stranded DNA was identified by acridine orange fluorescence method. The percentage of DNA fragmentation in LNV sperm (29%) was significantly higher (P<0.001) than NN sperm (15.8%). Therefore, cleavage of genomic DNA in low molecular weight DNA fragments (mono and oligonucleosomes), and single strand breaks (nicks) in high molecular weight DNA occur more frequently in LNV. Identically, the percentage denatured stranded DNA in sperm with LNV (67.9%) was significantly higher (P <0.0001) than NN sperm (33%). The high level of denatured DNA in sperm with LNV suggests precocious decondensation and disaggregation of sperm chromatin fibers. Our results support an association between LNV sperm and DNA damage, and the routine selection and injection of morphological motile sperm at high magnification for ICSI. The adverse effect (DNA fragmentation or denaturation) leads to concern particularly about the possibility of iatrogenic transmission of genetic abnormalities. Copyright - SBRA - Sociedade Brasileira de Reprodução Assistida.

Nuclear data for proton beam radiotherapy

The need for a program of work focused on the nuclear data evaluation of chargedparticle reactions has arisen recently due to their increasing use in cancer therapy. This project, as part of that program, has as its main goal the selection and comparison of nuclear data for nuclear reactions induced by protons at low to intermediate energies (E < 250 MeV). The methodology of selection was based on the data base EXFOR and the compilations of radionuclide production cross sections of N. Sobolevsky. For the purpose of comparison and evaluation, theoretical calculations with the reaction model code EMPIRE-II are being used. © 2009 American Institute of Physics.

Cytoplasmic and nuclear morphometric parameters in cytologic preparations of canine cutaneous mast cell tumors

Thirty fine-needle biopsy (FNB) samples from 28 dogs subjected to surgical resection of cutaneous mast cell tumors (MCTs) were stained with Giemsa. At least 100 neoplastic cells from each cytology slide were evaluated by morphometric analysis. The parameters were: area, perimeter of the cell, cytoplasm, nucleus and circumference factor. MCTs of grade III had a mean cellular area of 231.70 μm2 ± 57.1, and grade II had a mean of 252.30 μm2 ± 55.0. Cellular perimeter was 61.20 ± 7.1 in grade II and 59.1 ± 8.6 in grade III. Cellular parameters were not statistically different between grades (p>.05). Mean nuclear area was 88.90 μm2 ± 19 in grade III and 72.30 μm2 ± 13.9 in grade II, with statistical difference between grades (P =.011). Mean nuclear perimeter was 32.40 ìm ± 3.0 in grade II and 35.70 ìm ± 4.0 in grade III, with statistical difference between grades (P =.018). Mean nuclear circumference factor was 1.0 ± 0.33 in grade II and 1.1 ± 0.28 in grade III, with no statistical difference between grades (P = 0.78). Nuclear-tocytoplasmic ratio in grade II was 0.29 ±.07 and 0.39 ±.08 in grade III, with statistical difference (P =.02). The number of binucleated and multinucleated cells and mitotic figures was significantly increased in grade III MCTs (P <.001). In conclusion, the number of mitotic figures, presence of binucleation and multinucleation, and nuclear-to-cytoplasmic ratio can help to guide a profile of MCT aggressiveness in cytologic preparations.

Preparedness for rain during sunny weather: Caribbean environmental sustainability in a nuclear age

Includes bibliography

Waves generated by two or more ships in a channel

The numerical model FUNWAVE+Ship simulates the generation and propagation of ship waves to shore, including phenomena such as refraction, diffraction, currents and breaking of waves. The interaction of two wave trains, generated by ships moving either in the same direction at different speeds or in opposite directions, is studied. Focus is given to the wave orbital velocities and to the free surface pattern.

J/Ψ mass shift and J/Ψ-nuclear bound state

We calculate mass shift of the J/Ψ meson in nuclear matter arising from the modification of DD, DD* and D*D* meson loop contributions to the J/Ψ self-energy. The estimate includes the in-medium D and D* meson masses consistently. The J/Ψ mass shift (scalar potential) calculated is negative (attractive), and is complementary to the attractive potential obtained from the QCD color van der Waals forces. Some results for the J/Ψ -nuclear bound state energies are also presented. © 2011 American Institute of Physics.

La familia nuclear y extendida en áreas urbanas de la Argentina, el Brasil y Chile

Incluye Bibliografía

Energía nuclear: proyecto de resolución aprobado por el Comité II el 25 de mayo de 1957

Incluye Bibliografía

Nuclear energy: draft resolution approved by Committee II on 25 May 1957

Incluye Bibliografía

J/Ψ in nuclear matter

We report on recent estimates of the J/Ψ mass shift in infinite nuclear matter and finite nuclei arising from in-medium D and D* meson loops. The density dependence of the J/Ψ mass shift is evaluated employing medium-modified D and D* meson masses derived within the quark-meson coupling model. Using a local density approximation, J/Ψ-nuclear bound state energies are calculated for a range of nuclei. We predict that J/Ψ-nuclear bound states should be observed with a clear signal in experiments, provided the J/Ψ meson is produced in recoilless kinematics. © Published under licence by IOP Publishing Ltd.