SUMMARY
Rock joints are often filled with weak medium, for example, saturated clay or sand, of viscoelastic nature. Their effects on wave propagation can be modelled as displacement and stress ...discontinuity conditions. The viscoelastic behaviour of the filled joint can be described by either the Kelvin or the Maxwell models. The analytical solutions for wave propagation across a single joint are derived in this paper by accounting for the incident angle, the non‐dimensional joint stiffness, the non‐dimensional joint viscosity and the acoustic impedance ratio of the filled joint. It is shown that the viscoelastic behaviour results in dissipation of wave energy and frequency dependence of the reflection and transmission coefficients. Based on curve fitting of the experimental data of P‐wave propagation across a single joint filled with saturated sand, both the Kelvin and Maxwell models are found to reproduce the behaviour of the filled joint, in terms of the amplitude and frequency contents. Then, wave transmission across a filled joint set is studied with the virtual wave source method and the scattering matrix method, where multiple wave reflections among joints are taken into account. It is shown that the non‐dimensional joint spacing and the number of joints have significant effects on the transmission coefficients.
Human papillomavirus (HPV) is the agent of the most common sexually transmitted diseases causing a variety of clinical manifestations ranging from warts to cancer. Oncogenic HPV infection is the ...major cause of cervical cancer and less frequently of penile cancers. Its presence in semen is widely known, but the effects on fertility are still controversial. We developed a new approach to evaluate virus localisation in the different semen components. We analysed also the specific genotype localisation and viral DNA quantity by qPCR. Results show that HPV DNA can be identified in every fraction of semen: spermatozoa, somatic cells and seminal plasma. Different samples can contain the HPV DNA in different fractions and several HPV genotypes can be found in the same fraction. Additionally, different fractions may contain multiple HPV genotypes in different relative quantity. We analysed the wholeness of HPV DNA in sperm cells by qPCR. In one sample more than half of viral genomes were defective, suggesting a possible recombination event. The new method allows to easily distinguish different sperm infections and to observe the possible effects on semen. The data support the proposed role of HPV in decreased fertility and prompt new possible consequences of the infection in semen.
The determination of rock mass dynamic parameters including the influence of joints/discontinuities on wave propagation is of interest for solving problems in geophysics, rock protective engineering, ...rock dynamics and earthquake engineering. This topic is covered in this paper by means of laboratory tests on intact and jointed rock specimens performed with the resonant column apparatus (RCA). Attention is dedicated to the determination, with this equipment, generally used for testing soils, of the shear modulus at small strain and the damping ratio of intact and jointed rock specimens. A correction procedure based on the RCA tests performed on aluminium specimens is described. The results of the tests performed are analysed in detail. Three-dimensional distinct element method modelling is used to evaluate the applicability of the RCA and the correctness of the laboratory tests performed. A comparison with the results obtained using the scattering matrix method is also presented.
Every year, fee awards enable millions of people to obtain access to justice and strengthen the deterrent effect of the law by motivating lawyers to handle class actions. But little research exists ...on why judges award the amounts they do or whether they size fee awards correctly. The process remains a black box. Through a detailed study of 431 secunties class actions that settled in federal district courts from 2007 through 2012, this Article presents the first empirical study to peer inside that black box. In contrast to prior analyses, this study relies on the actual court filings in each case to create an original, comprehensive data set on all points at which federal judges are likely to consider issues relating to fees. These data enable us to paint a picture of the fee-setting process that is unusually detailed and nuanced—and that falsifies many common beliefs. Among this Article's major findings are that: (1) federal judges often deviate from the path Congress laid out in the Private Securities Litigation Reform Act of 1995 (PSLRA), which requires lead plaintiffs to set the terms of class counsel's retention and federal judges to serve as bacfotops against abuses; (2) fees are generally lower infederai districts that see a high volume of securities class actions than in districts that handle lower volumes; (3) judges in high-volume districts are significantly more likely to cut fees than low-volume judges; (4) the "decrease-increase" rule, according to which fee percentages decline as settlements become larger, operates mainly in high-volume districts; and (5) judges appear to cut fees randomly, typically with very little explanation for why they did so. Finally, this Article finds that so-called lodestar crosschecks," which are supposed to help judges moderate fee awards, have unintended effects. All else equal, fee awards are significantly higher when fee requests include cross-checks than when lawyers use only the percentage method. A plausible explanation is that lawyers are anticipating judges' reactions to fee requests and acting strategically. They include lodestar information when their requests may appear excessive and they omit it either when they expect judges to grant their requests or they think that the lodestar data will not help their cause. In sum, there is little evidence that courts' current actions in securities class actions move class counsel's fees closer to the "right price. "This Article therefore proposes a set of procedural reforms, which courts could easily adopt, to make fee-setting in securities class actions more transparent, more compatible with the PSLRA's normative goals, and more predictable. The reforms would encourage lawyers to invest in class actions at more appropriate levels, with salutary effects for plaintiffs and the integrity of the financial markets.
To evaluate the role of vaginal fractional CO2 laser treatment in the relief of Overactive Bladder (OAB) symptoms in post-menopausal women.
Post-menopausal women who complained of one or more ...symptoms related to vulvo-vaginal atrophy (VVA), who experienced symptoms of OAB and who underwent vaginal treatment with fractional CO2 laser were enrolled in the study. At baseline (T0) and 30 days post-treatment T1), vaginal status (using Vaginal Health Index - VHI), subjective intensity of VVA symptoms (using a visual analog scale - VAS) and micturition diary were evaluated. OAB symptoms were also assessed using a validated questionnaire.
Thirty patients were enrolled. A statistically significant improvement in VVA symptoms was observed and in VHI at T1 (p < 0.0001). A significant improvement was also identified in the micturition diary, in number of urge episodes and OAB-q (p < 0.0001). Nine of the 30 patients suffered from incontinence episodes and had improved at T1.
We showed that fractionated CO2 laser vaginal treatment has proved to be effective in improving OAB symptoms in post-menopausal women. Moreover, it is a safe and efficacious measure for the relief of VVA related conditions. Further long-term studies are needed to confirm these preliminary results.
Menopausal transition entails a progressive decrease in hormone production by the ovaries that lead to important physical and psychological changes that could significantly affect quality of life. ...Hormone replacement therapy (HRT) administered from the onset of menopausal symptoms usually improves quality of life and life expectancy. Nevertheless, it is not risk-free. Ovarian tissue cryopreservation (OTC) has been investigated as a potential new strategy for delaying menopause and/or to avoid HRT. This review analyzes the critical points of HRT to assess whether OTC and subsequent reimplantation can affect postmenopausal management. We assessed available randomized clinical trials in PubMed, Cochrane Library, ISI web of science, and Scopus from August 2021 to November 2022, including studies and trials evaluating the efficacy of OTC in both cancer and menopausal patients, the efficacy of freezing techniques and the possible clinical scenarios that OTC can open, even from the standpoint of legal and ethical issues arising as such innovative techniques become mainstream. Lower duration of the graft and efficacy on estrogen secretions at a physiological and safer concentration of estrogen than conventional HRT based on hormonal supplements. OTC can reportedly trigger estrogen secretions at a lower and safer physiological concentration than conventional HRT. OTC and subsequent reimplantation remain a valid fertility-sparing approach in patients undergoing gonadotoxic treatments. Further studies are needed to better evaluate its safety and efficacy within postmenopausal therapy management and in order to lay out widely shared and evidence-based guidelines and best practices and perform such novel and innovative techniques in a legally and ethically safe fashion, in the best interest of patients and healthcare professionals.
Propagation of elastic waves in discontinuous media is studied in this paper by the scattering matrix method (SMM). An electromagnetic transmission line analogy is also used to set up the ...mathematical model. The SMM operates in the frequency domain and allows for all wave polarizations (P, SV and SH). Rock masses are examples of discontinuous media in which the discontinuities (fractures or joints) influence wave propagation. Both elastic and viscoelastic joints are considered and the latter are described by Kelvin–Voigt, Maxwell and Burgers models. Rock joints with Coulomb slip behavior are also analyzed, by applying the averaging principle of Caughy (J Appl Mech 27:640–643,
1960
). The evaluation of the effects of periodic discontinuities in a homogeneous medium is presented by introducing the concept of Bloch waves. The dispersion curves of these waves are useful to explain the existence of frequency bands of strong attenuation, also in the case of lossless (perfectly elastic) structures. Simple expressions of transmission and reflection coefficients are obtained. Finally, the SMM results are compared with those computed via the distinct element method (DEM). The comparisons are performed on a medium with joints with Coulomb slip behavior and the agreement is satisfactory, although the SMM must be applied in conjunction with the equivalent linearization technique. Even if the DEM is much more general, the SMM in these simple cases is extremely faster and provides a higher physical insight.
Human PapillomaVirus (HPV) vaccination has been introduced in recent years in clinical practice as the most effective primary prevention strategy for cervical cancer and HPV-induced lesions, either ...pre-malignant or benign. Since its introduction, HPV vaccination has been progressively demonstrated as extremely effective in preventing extra-genital and male diseases also; furthermore, non only adolescents but adult subjects have been investigated and reported as positively responding to vaccine immunostimulation. More recently, effectiveness of post-treatment vaccine administration has been preliminarily investigated with very promising results in terms of decreased recurrences. On this basis, we report an Italian-focused picture of the state of the art and take a position in favour of the extension of HPV vaccination to male adolescents, to older age groups and to already treated subjects.
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