Single-layer spherical geodesic domes interacting with a network of inflatable beams

In this paper we propose an example of a thin geodesic spherical dome composed by a lattice of inflatable interacting beams. The geometry of the lattice is determined by searching for the minimum variation of the characteristic dimensions of the elements that make up the dome (length of the bars and area of the panels). A first illustration of the mechanical response of the structure is given, with reference to the loads that usually are assumed to act on this type of shell

Experimental investigation of in-plane loaded timber-framed rammed earth panels. Part I: Monotonic shear-compression tests

Rammed earth walls show comparatively good performances with respect to vertical loads, while their stiffness and strength against horizontal loads are often unsatisfactory. Preliminary indications about the timber-framed rammed earth panel (TREP) stiffness and load bearing capacity have been obtained from a first experimental study that has been expressively set up and performed to investigate the TREP in-plane static behavior. The present part I, together with the subsequent part II (companion paper), illustrates and discusses the key experimental results obtained from the compression-shear loading tests performed on rammed earth panels reinforced by a contouring timber frame. In the present part I of the paper, the monotonic loading tests are carefully analyzed, the results are discussed, and the detected damage modes are explained. The results seem to show that the reinforcing timber frame provides a substantial benefit enabling the development of an effective “strut-and-tie” resisting mechanism that effectively exploits the compressive strength of the rammed earth panel and promotes a ductile failure mode

Experimental investigation of in-plane loaded timber-framed rammed earth panels. Part II: cyclic shear-compression tests

Preliminary indications about the timber-framed rammed earth panel (TREP) stiffness and load bearing capacity have been obtained from a first experimental study that has been expressively set up and performed to investigate the TREP in-plane static behavior. The present part II, together with the foregoing part I (companion paper), illustrates and discusses the key experimental results obtained from the compression-shear loading tests performed on rammed earth panels reinforced by a contouring timber frame. In the present part II of the paper, the cyclic loading tests on two TREP elements and one bare timber frame are carefully analyzed, the results are discussed, in terms of load capacity and ductility, and the detected damage modes are explained. The results seem to show that the reinforcing timber frame provides a substantial benefit enabling the development of an effective “strut-and-tie” resisting mechanism that effectively exploits the compressive strength of the rammed earth panel and promotes a ductile failure mode.(undefined

Primary Corneal Squamous Cell Carcinoma in a Dog: Clinical and Histopathological Evaluation

An 8-year-old male pug with a 12-month history of a progressive nonpainful mass on the left cornea was evaluated. Ocular examination showed a severe bilateral keratoconjunctivitis sicca, pigmentary keratitis, and an exophytic irregular pink mass occupying approximately 75% of the total corneal surface of the left eye. A squamous cell carcinoma (SCC) was suspected on cytology, and clinical investigations showed no evidence of metastases. A transpalpebral enucleation was therefore performed, and the diagnosis of SCC was confirmed on histopathology. Immunohistochemical investigations showed that the neoplastic cells were pan-cytokeratin positive and vimentin negative. Additionally, nuclei immunoreactive to Ki-67 antigen were detected. Tumor cells were also negative to p53. Immunoreactivity to COX-2 was found in less than 10% of the neoplastic cells. No adjuvant therapies were instituted, and no evidence of local recurrence or distance metastasis was identified during the 24-month follow-up period

Covid-19 And Rheumatic Autoimmune Systemic Diseases: Role of Pre-Existing Lung Involvement and Ongoing Treatments

The Covid-19 pandemic may have a deleterious impact on patients with autoimmune systemic diseases (ASD) due to their deep immune-system alterations

A Cryogenic Silicon Interferometer for Gravitational-wave Detection

The detection of gravitational waves from compact binary mergers by LIGO has opened the era of gravitational wave astronomy, revealing a previously hidden side of the cosmos. To maximize the reach of the existing LIGO observatory facilities, we have designed a new instrument able to detect gravitational waves at distances 5 times further away than possible with Advanced LIGO, or at greater than 100 times the event rate. Observations with this new instrument will make possible dramatic steps toward understanding the physics of the nearby Universe, as well as observing the Universe out to cosmological distances by the detection of binary black hole coalescences. This article presents the instrument design and a quantitative analysis of the anticipated noise floor

A Cryogenic Silicon Interferometer for Gravitational-wave Detection

The detection of gravitational waves from compact binary mergers by LIGO has opened the era of gravitational wave astronomy, revealing a previously hidden side of the cosmos. To maximize the reach of the existing LIGO observatory facilities, we have designed a new instrument that will have 5 times the range of Advanced LIGO, or greater than 100 times the event rate. Observations with this new instrument will make possible dramatic steps toward understanding the physics of the nearby universe, as well as observing the universe out to cosmological distances by the detection of binary black hole coalescences. This article presents the instrument design and a quantitative analysis of the anticipated noise floor

The population of merging compact binaries inferred using gravitational waves through GWTC-3

We report on the population properties of 76 compact binary mergers detected with gravitational waves below a false alarm rate of 1 per year through GWTC-3. The catalog contains three classes of binary mergers: BBH, BNS, and NSBH mergers. We infer the BNS merger rate to be between 10 $\rm{Gpc^{-3} yr^{-1}}$ and 1700 $\rm{Gpc^{-3} yr^{-1}}$ and the NSBH merger rate to be between 7.8 $\rm{Gpc^{-3}\, yr^{-1}}$ and 140 $\rm{Gpc^{-3} yr^{-1}}$ , assuming a constant rate density versus comoving volume and taking the union of 90% credible intervals for methods used in this work. Accounting for the BBH merger rate to evolve with redshift, we find the BBH merger rate to be between 17.9 $\rm{Gpc^{-3}\, yr^{-1}}$ and 44 $\rm{Gpc^{-3}\, yr^{-1}}$ at a fiducial redshift (z=0.2). We obtain a broad neutron star mass distribution extending from $1.2^{+0.1}_{-0.2} M_\odot$ to $2.0^{+0.3}_{-0.3} M_\odot$. We can confidently identify a rapid decrease in merger rate versus component mass between neutron star-like masses and black-hole-like masses, but there is no evidence that the merger rate increases again before 10 $M_\odot$. We also find the BBH mass distribution has localized over- and under-densities relative to a power law distribution. While we continue to find the mass distribution of a binary's more massive component strongly decreases as a function of primary mass, we observe no evidence of a strongly suppressed merger rate above $\sim 60 M_\odot$. The rate of BBH mergers is observed to increase with redshift at a rate proportional to $(1+z)^{\kappa}$ with $\kappa = 2.9^{+1.7}_{-1.8}$ for $z\lesssim 1$. Observed black hole spins are small, with half of spin magnitudes below $\chi_i \simeq 0.25$. We observe evidence of negative aligned spins in the population, and an increase in spin magnitude for systems with more unequal mass ratio

Approximated Solutions for Axisymmetric Wrinkled Inflated Membranes

The axisymmetric inflation problem for a wrinkled membrane is solved by means of a sim- ple nonlinear ordinary differential equation. The solution is illustrated in full details. Both the free and constrained cases are addressed, in the limit case where the membrane is fully wrinkled. In the constrained inflation problem, no slippage is allowed between the membrane and the constraining surfaces. It is shown that an actual membrane can in no way reach the fully wrinkled configuration during free inflation, regardless of the membrane’s initial configuration and constituent material. The fully wrinkled solution is compared to some FE results obtained by means of an expressly developed iterative–incremental procedure. When the values of the inflating pressure and length of the meridian lie within a suitable applicability range, the fully wrinkled solution may rep- resent a reasonable approximation of the actual solution. A comparison with some numerical and experimental results available in the literature is illustrated