Durability and variability of the acoustical performance of rubberized road surfaces

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A new in situ test for the assessment of the rock-burst alarm threshold during tunnelling

Rock-burst is one of the most serious risks associated with hard rock tunnelling and mining at high depths. Monitoring of acoustic emissions emitted by the rock-mass during excavation and their interpretation now permits the early assessment of failure events and makes the safe management of the construction works possible. A reliable set-up of the alarm threshold is thus fundamental for the correct implementation of the procedures planned to minimise rock-burst related risk. This paper focuses on a novel in situ test specifically developed to provide an experimental basis for a more accurate assessment of the alarm threshold during tunnelling, representative of the local geomechanical conditions. The test, thanks to the compression induced by two flat jacks at the tunnel side wall, produces an artificial failure process during which acoustic emissions are measured and correlated to the mechanical response of the rock-mass, without the typical limitations of scale that characterised the laboratory experiments. The new methodology, named the Mules method, was successfully tested during the excavation of some stretches of the Brenner Base Tunnel in the Brixner granite, affected by mild spalling episodes. The case-history is fully described in the paper to illustrate the practical application of the proposed approach

A wireless crackmeters network for the analysis of rock falls at the Pietra di Bismantova natural heritage site (Northern Apennines, Italy)

The Pietra di Bismantova (Northern Apennines, Italy) is a large calcareous sandstone rock slab which is distinctively bordered by sub-vertical cliffs that are affected by rock falls, a risk for people visiting the area and for key assets located at the foot of this natural heritage site. A wireless sensor network based on wireless nodes, crack meters and thermometers has been made operative in January 2015 in order to study the response of fractures to changing environmental conditions and support the spatial and temporal zonation of rock fall hazard in this natural heritage site. Results from the first eight months of monitoring show that intense snowfall and low temperatures can determine short-term pulses of fracture opening while the increase of temperature throughout summer determines long-term fracture closing trends. Moreover, as soon as February 2015 one of the crack meters monitored the rapid trend of crack opening that occurred prior to the failure of a large rock slab of about 200 cubic meters

Optimal simple rules and the lower bound on the nominal interest rate in the Christiano–Eichenbaum–Evans model of the US business cycle

Schmitt-Grohé and Uribe (NBER wp 10724, 2004b) analyzes the optimal, simple and implementable monetary policy rules in a medium-scale macromodel, as the one proposed by Christiano et al. (J Polit Econ 113:1–45, 2005). In doing so, they use a sensible, but somewhat arbitrary constraint to account for the lower bound condition on the nominal interest rate. In this work, we check the robustness of their main results to such a criteria. We find that the optimal policies are actually absolutely robust to the easing of this criterion for all the diff erent cases considered.info:eu-repo/semantics/publishedVersio

Mutational screening of splicing factor genes in cases with autosomal dominant retinitis pigmentosa

Purpose Mutations in genes encoding proteins from the tri-snRNP complex of the spliceosome account for more than 12% of cases of autosomal dominant retinitis pigmentosa (adRP). Although the exact mechanism by which splicing factor defects trigger photoreceptor death is not completely clear, their role in retinitis pigmentosa has been demonstrated by several genetic and functional studies. To test for possible novel associations between splicing factors and adRP, we screened four tri-snRNP splicing factor genes (EFTUD2, PRPF4, NHP2L1, and AAR2) as candidate disease genes. Methods: We screened up to 303 patients with adRP from Europe and North America who did not carry known RP mutations. Exon-PCR and Sanger methods were used to sequence the NHP2L1 and AAR2 genes, while the sequences of EFTUD2 and PRPF4 were obtained by using long-range PCRs spanning coding and non-coding regions followed by next-generation sequencing. Results: We detected novel missense changes in individual patients in the sequence of the genes PRPF4 and EFTUD2, but the role of these changes in relationship to disease could not be verified. In one other patient we identified a novel nucleotide substitution in the 5′ untranslated region (UTR) of NHP2L1, which did not segregate with the disease in the family. Conclusions: The absence of clearly pathogenic mutations in the candidate genes screened in our cohort suggests that EFTUD2, PRPF4, NHP2L1, and AAR2 are either not involved in adRP or are associated with the disease in rare instances, at least as observed in this study in patients of European and North American origin

Vinblastine, bleomycin, and methotrexate chemotherapy plus irradiation for patients with early-stage, favorable Hodgkin lymphoma - The experience of the gruppo italiano studio linfomi

BACKGROUND. The acknowledged effectiveness of vinblastine, bleomycin, and methotrexate (VBM) chemotherapy in patients with early-stage Hodgkin lymphoma has been associated with conflicting toxicity reports. METHODS. One hundred forty-three patients were evaluated clinically and had favorable Stage IA or IIA Hodgkin lymphoma. Ninety-three patients were treated with the standard VBM schedule combined with extended-field radiotherapy (EFRT), leaving the choice of the therapeutic sequence free. Fifty subsequent patients were treated with a slightly modified VBM schedule (VbMp) combined with RT limited to involved fields (IF-RT) and delivered only after the end of chemotherapy. In the VbMp schedule, intervals between cycles were 21 days instead of 28 days, bleomycin doses were reduced, small doses of prednisone were given orally, and the interval before RT was prolonged. RESULTS. Clinical response was complete in 96% of patients who were treated with VBM plus EF-RT and in 94% of patients who were treated with VbMp plus IF-RT. Recurrence rates were nearly identical (12% and 11%, respectively) over necessarily different follow-up (91 months and 33 months, respectively). Hematologic toxicity was tolerable in both trials, and pulmonary side effects were moderate in the first trial and negligible in the second. On the whole, treatment was tolerated better when RT followed chemotherapy. CONCLUSIONS. The VBM regimen was confirmed to be effective in patients with early-stage Hodgkin lymphoma. Administration of all cycles before RT improved tolerance; pulmonary toxicity probably is mitigated further by reduced bleomycin doses, mild prednisone therapy, and a more prolonged resting interval before RT. A slightly higher recurrence rate was expectable in the VBM plus IF-RT trial despite the actual intensification of vinblastine and methotrexate

Long-term survival of stage I multiple myeloma given chemotherapy just after diagnosis or at progression of the disease: a multicentre randomized study

We conducted a randomized trial to evaluate whether melphalan-prednisone (MPH-P) treatment administered just after diagnosis improves survival of stage I multiple myeloma (MM). Between January 1987 and March 1993, 145 consecutive previously untreated patients with stage I MM were randomized between treatment with MPH-P (administered for 4 days every 6 weeks) just after diagnosis and treatment only at disease progression. Survival was not influenced by MPH-P treatment either administered just after diagnosis or at disease progression (64 vs 71 months respectively). Comparing the first with the second group the odds ratio of death is 1.17 (95% confidence interval 0.57–2.42;P = 0.64). Disease progression occurred within a year in about 50% of patients who were initially untreated. Response rate was similar in both groups, but duration of response was shorter in patients who were treated at disease progression (48 vs 79 months, P = 0.044). Patients actually treated at disease progression (34/70) survived shorter than those who had neither disease progression nor treatment (56 vs > 92 months;P = 0.005). Starting MPH-P just after diagnosis does not improve survival and response rate in stage I MM, with respect to deferring therapy until disease progression. However, patients with stage I MM randomized to have treatment delayed and who actually progressed and were treated had shorter survival than those with stable disease and no treatment. Biologic or other disease features could identify these subgroups of patients. © 2000 Cancer Research Campaig