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The causal role of human papillomavirus infections in cervical cancer has been documented beyond reasonable doubt. The association is present in virtually all cervical cancer cases worldwide. It is the [...]

Several different techniques are employed to explain the magnetization and the electron behavior exhibited by the different [R.sub.2][Ru.sub.3][Ga.sub.9] (R = Ce and U) compounds. The resistivity is shown to be inversely proportional to the temperature of the system.

Abstract: We report the synthesis of the new compounds R15Si9C with R=Sm, Gd–Er, Y and R15Ge9C with R=Ce, Pr and Nd. These compounds crystallize in the hexagonal La15Ge9Fe structure type (hP50, P63mc, Z =2) which is an ordered superstructure of La5Ge3 (Mn5Si3-type, hP16, P63/mcm, Z =2). The superstructure is absent in a single-phase R5Ge3C0.33 alloy with R=Sm and Gd. The addition of interstitial carbon modifies the magnetic properties significantly as regards the magnetic transition temperature and the nature of the magnetic ordering. Carbon doping induces mostly a ferromagnetic or ferrimagnetic configuration. The preponderance of ferromagnetic interactions in the superstructure compounds, with respect to the parent phases, can tentatively be attributed to a change in the sign of the RKKY interactions. The dense Kondo lattice state of Ce in ferrimagnetic Ce5Ge3 is preserved in Ce15Ge9C. Large coercive fields (∼4–5kOe) at low temperatures are observed in most compounds, which exceed ∼50kOe in the two Sm based compound. [Copyright &y& Elsevier]

Abstract: We report the effect of replacing Cu by Pd in RCu5 (R=Pr, Nd, Sm and Eu). The parent RCu5 compounds crystallize in the hexagonal CaCu5-type structure. The hexagonal symmetry is retained in PrCu4Pd and EuCu5− x Pd x (x=1 and 2) but the crystal structure changes to cubic AuBe5-type in PrCu3Pd2, NdCu5− x Pd x (x=1 and 2) and SmCu4Pd. Substitution with Pd leads to lattice expansion and modifies the magnetic behavior. While PrCu5 is known to be a van-Vleck paramagnet with a singlet ground state, PrCu4Pd and PrCu3Pd2 show ferromagnetic-like behavior at low temperatures. SmCu4Pd orders ferromagnetically near 28K in contrast to the antiferromagnetic nature of the parent SmCu5. The divalent nature of the Eu ions in EuCu5 is retained in the ternary alloys, but the Curie temperature is reduced from 57 to 24.5 and 14.5K in EuCu4Pd and EuCu3Pd2, respectively, inferred from the location of peak in the heat capacity of these two compounds. The magnetic hyperfine field at the Eu nucleus measured with 151Eu Mössbauer spectroscopy in the ternary Eu-alloys is comparable to that in EuCu5. The magnetic behavior of NdCu4Pd is similar to that reported in NdCu5. The zero-field-cooled, low-field magnetization of NdCu3Pd2 shows a region of diamagnetic behavior roughly between 21 and 4K, but the field-cooled response is positive. [Copyright &y& Elsevier]

Abstract: The binary compound CeCu5 has the hexagonal, CaCu5 type structure and orders antiferromagnetically near 4 K. We find that Cu can be replaced by Pd up to at least CeCu3Pd2. While CeCu4Pd retains the hexagonal symmetry of the parent CeCu5, interestingly CeCu3Pd2 crystallizes in the cubic AuBe5 type structure. On the other hand, in the La analogs the hexagonal structure is retained up to at least LaCu3Pd2. Magnetization data reveal that Ce ions remain trivalent in both compounds. Heat capacity data indicate that CeCu4Pd and CeCu3Pd2 order magnetically below 1.8 K. While the resistivity of CeCu4Pd shows normal metallic behavior, the data show that CeCu3Pd2 is a dense Kondo lattice. [Copyright &y& Elsevier]

Abstract: We have identified a new compound of composition U2Fe3Ge, which crystallises in the hexagonal, C14 Laves phase MgZn2 type structure. Fe and Ge occupy randomly the sites of the Zn sublattice. The lattice volume increases by about 4.3% compared to the parent cubic Laves phase compound UFe2. The magnetic properties of U2Fe3Ge have been probed by using magnetization, resistivity, heat capacity and 57Fe Mössbauer spectroscopy. The compound orders ferromagnetically near 55 K in a state which is magnetically weaker than in UFe2. The latter is inferred from a lower saturated magnetic moment and hyperfine field at the Fe site. Resistivity shows a behaviour at low temperatures. Both the coefficient of the term in the resistivity and the Sommerfeld coefficient, , in U2Fe3Ge are slightly higher compared to that in UFe2. [Copyright &y& Elsevier]

Four-hundred-forty-five husbands of women with invasive cervical carcinoma, 165 of women with in situ cervical cancer, and 717 of control women (age range 19-82 years) were interviewed and a sample of exfoliated cells from the penis obtained in seven case-control studies conducted by the International Agency for Research on Cancer. The characteristics of human papillomavirus-positive and human papillomavirus-negative husbands were compared using odds ratios and 95% confidence intervals. Thirteen per cent of the husbands of control women, 18% of the husbands of women with invasive cervical carcinoma, and 21% of the husbands of in situ cervical carcinoma women were positive for penile human papillomavirus DNA. Human papillomavirus 16 was detected in 45 husbands, human papillomavirus 18, 31 or 33 in 19, and human papillomavirus 6/11 in 6, but the majority of human papillomavirus infection (158) was with other or unspecified human papillomavirus types. The same human papillomavirus type was seldom identified in both husband and wife. The strongest variation in penile human papillomavirus infection was by country, with percentages among the husbands of control women ranging between 3% in Spain and 39% in Brazil. Having had over 50 lifetime sexual partners, compared with only one, was associated with an odds ratio of 2.3. [ABSTRACT FROM AUTHOR]

Studies the interaction of human immunodeficiency virus type 1 and human herpesvirus type 8 infections on the incidence of Kaposi's sarcoma (KS). Descriptive statistics; Univariate and multivariate analysis; Characteristics of the KS cases.