Lattice Simulation of Nuclear Multifragmentation

Motivated by the decade-long debate over the issue of criticality supposedly observed in nuclear multifragmentation, we propose a dynamical lattice model to simulate the phenomenon. Its Ising Hamiltonian mimics a short range attractive interaction which competes with a thermal-like dissipative process. The results here presented, generated through an event-by-event analysis, are in agreement with both experiment and those produced by a percolative (non-dynamical) model.Comment: 8 pages, 3 figure

Earthen construction: structural vulnerabilities and retrofit solutions for seismic actions

Earthen structures present very appealing characteristics regarding a more sustainable practice with the preservation of our natural resources. However, when subjected to earthquake ground motions, this type of construction may present a deficient performance, which may cause significant human losses and important structural damage. The seismic response of earthen structures is typically characterized by fragile failures. There are several examples of recent earthquakes that affected earthen buildings in a severe way, evidencing the vulnerability of this type of construction, like the El Salvador earthquake, in 2001, the Bam, Iran earthquake, in 2003, the Pisco, Peru earthquake, in 2007 and the Maule, Chile earthquake, in 2010. The construction of earth structures on earthquake-prone areas must be carefully studied and should include seismic reinforcement solutions in order to improve their seismic performance. In this paper, the performance of earthen structures in recent earthquakes will be examined, analyzing failure modes inherent to these particular construction materials and associated construction techniques. Also, seismic reinforcement approaches and techniques will be presented in a comprehensive manner. Examples of tests conducted for the assessment of retrofitting solutions efficiency will be presented, and the results obtained will be discussed

Lactobacillus crispatus as the etiological agent in cytolytic vaginosis

Introduction: Lactobacillus spp. dominate the vaginal niche but can also be involved in other vaginal dysbiosis, such as cytolytic vaginosis (CV), which remains poorly studied. It is characterized by a cryptic symptomatology, that often confounds the clinic. Goals: The aim of this work was to search for the etiological agent of CV, by studying the vaginal microbiome and metabolomics of women afflicted with this disease and compare it with women with other clinical diagnostic. Methods: Twenty-one vaginal washes have been collected from women attending a gynaecology consultation of a private clinic. The samples were categorized according with clinical diagnosis at the time of sampling (CV, 11; vulvovaginal candidosis, 8; Healthy, 2). The distribution of bacterial species, and their prevalence was assessed by next-generation sequencing of the 16S V4 region. In addition, total lactate D-lactic acid and L-lactic acid was quantified in all washes by a commercial kit, as well as lactate dehydrogenase (LDH) activity. Results: L. crispatus was dominant (>70%) in all CV samples. Lactate was increased in CV in comparison with other cases. The presence of D-lactic acid isomer was associated with presence of L. crispatus. LDH activity was increased in vaginal washes that tested positive for the presence of L. crispatus, however no direct association was found with CV cases. Discussion/Conclusions: The microbiome of women afflicted with CV was dominated in all cases by L. crispatus, contrarily with the results obtained for women diagnosed with other clinical symptomatology. In addition, the finding that an increase in D-lactic acid is associated with CV patients can be related to the role of L. crispatus in CV. The determination of LDH activity did not correlate exclusively with CV cases. On the other hand, D-lactic acid and total lactate quantification could be used as a valuable biomarker to diagnose this cryptic vaginal infection.info:eu-repo/semantics/publishedVersio

Assessment of Lactobacillus crispatus´ role in vaginal infections: friend or foe?

Lactobacillus spp. are the most prevalent microorganisms in the vaginal milleu. Several probiotic mechanisms have been associated with Lactobacillus, but the most relevant one is lactate production – resulting in a low pH value, typical of the healthy vagina. However, its pathogenic state is still unknown. We aim to elucidate the role of a commensal vaginal microorganism, Lactobacillus crispatus, in vaginal infections. Twenty-four vaginal washes have been collected from women attending a gynaecology consultation of a private clinic. The samples were categorized according with clinical diagnosis at the time of sampling. The distribution of bacterial species, and their prevalence was assessed by Next-Generation Sequencing of the 16S rRNA V4 region. In addition, L- and D-lactate concentration, and LDH enzymatic activity was quantified in all washes by a commercial kit. Detection of Candida spp. was performed by PCR. L. crispatus was dominant (>70%) in 11 out of 24 samples – diagnosed for vaginal atrophy (VA, 3), cytolytic vaginosis (CV, 2) and lactobacillosis (LB, 2). Lactate was increased in CV, LB and VA cases only. The remaining samples, diagnosed for vulvovaginal candidosis in its majority, had lower prevalence of L. crispatus; and lower to moderate lactate metabolite. There was not a direct relationship between LDH enzymatic activity and clinical diagnosis. L. crispatus dominance, associated with increased lactate production, was observed in CV, LB and VA cases. These results indicate that this microorganism might have a role in dysbiosis of the vagina associated with these specific pathologies.info:eu-repo/semantics/publishedVersio

Role of Lactobacillus crispatus in vaginal infections: insights from metagenomics and metabolomics studies

Objective: Lactobacillus spp. constitute the most prevalent bacterial microorganism in the vaginal milleu. Several probiotic mechanisms have been associated with Lactobacillus, but the most relevant one is lactate production – resulting in a low pH value, typical of the healthy vagina. We aim to elucidate the role of a native vaginal microorganism, Lactobacillus crispatus, in vaginal infections. Methods: Twenty-four vaginal washes have been collected from women (mean 38±14 years of age) attending a gynecology consultation of a private clinic. The samples were categorized according with clinical diagnosis at the time of sampling. The distribution of bacterial species, and their prevalence was assessed by next-generation sequencing of the 16S V4 region. In addition, lactate was quantified in all washes by a commercial kit. Results: L. crispatus was dominant (>70%) in 11 out of 24 samples – diagnosed for vaginal atrophy (VA, 3), cytolytic vaginosis (CV, 2), lactobacillosis (LB, 2) and vulvovaginal candidosis (VVC, 1). For three samples, diagnostic was inconclusive. Lactate was increased in CV, LB and VA cases only. One sample, diagnosed with VVC had 23% dominance of L. crispatus; and lower lactate metabolite. L. crispatus was not detected in the remaining 12 cases (6 VVC, 4 VA, 1 healthy and 1 inconclusive). Of these, only 5 samples had moderate lactate metabolite. Conclusions: L. crispatus dominance, associated with increased lactate production, was observed in CV, LB and VA cases. These results indicate that this microorganism might have a role in dysbiosis of the vagina associated with these specific pathologies.info:eu-repo/semantics/publishedVersio