•Validation of a new simplified rational tying force method for the robustness/progressive collapse assessment of reinforced concrete systems.•Simplified tying method to reproduce catenary/membrane ...phase of reinforced concrete systems explicitly considering rotational ductility.•Comparison between experimental results and simplified tying force to establish the representative level of rotational ductility.•Suitability of the simplified tying force method as a robustness assessment framework for reinforced concrete structures for the next generation of Eurocodes.
The robustness of reinforced concrete (RC) structures is an important ongoing research topic in the civil engineering community. Especially in the last decades, the need for structural robustness assessment methods has become urgent, and several design methods have been proposed in codes and guidelines to mitigate the progressive collapse risk of reinforced concrete structures. The most used approaches are the Tying Force and Alternate Load Path methods. The first is typically applied as an indirect and prescriptive method where the building is considered mechanically tied together and able to enhance continuity and the resistance to progressive collapse. The second is a direct method, where the capacity of the structure to sustain the applied loads is evaluated after the loss of a load-bearing element, most effectively using advanced nonlinear structural analysis methods. In the context of the Tying Force method, the Eurocode is recognised to underestimate the tie force demands required by building structures subject to the loss of a load bearing member, which are better reflected in the USA UFC Guidelines. A new Tying Force method has been proposed by Izzuddin & Sio (2021) for the next generation of the Eurocodes, which addresses the shortcomings of the present Eurocode guidance, and provides a more comprehensive treatment than considered in the UFC code. The present paper is aimed specifically at the validation of the new Simplified Tying Force method (Izzuddin & Sio, 2021) for reinforced concrete structures, considering grillage and combined beam/slab floor systems, and considering the rotational ductility of such structures, which is explicitly considered in the new method.
Gain of 20q11.21 is one of the most common recurrent genomic aberrations in human pluripotent stem cells. Although it is known that overexpression of the antiapoptotic gene Bcl-xL confers a survival ...advantage to the abnormal cells, their differentiation capacity has not been fully investigated. RNA sequencing of mutant and control hESC lines, and a line transgenically overexpressing Bcl-xL, shows that overexpression of Bcl-xL is sufficient to cause most transcriptional changes induced by the gain of 20q11.21. Moreover, the differentially expressed genes in mutant and Bcl-xL overexpressing lines are enriched for genes involved in TGF-β- and SMAD-mediated signaling, and neuron differentiation. Finally, we show that this altered signaling has a dramatic negative effect on neuroectodermal differentiation, while the cells maintain their ability to differentiate to mesendoderm derivatives. These findings stress the importance of thorough genetic testing of the lines before their use in research or the clinic.
•Bcl-xL overexpression drives the transcriptomic profile of 20q11.21 mutant lines•20q11.21 mutant lines downregulate CHCHD2, a known TGF-β pathway modulator•Mutant lines differentially express genes involved in TGF-β and SMAD signaling•Mutant lines show impaired ectoderm commitment due to TGF-β signaling deregulation
In this article Spits and colleagues show that Bcl-xL overexpression is the main driver of the distinct transcriptomic profile of human embryonic stem cells with a gain of 20q11.21. The cells have an abnormal TGF-β- and SMAD-mediated signaling, which impairs commitment to neuroectoderm while differentiation to the other lineages remains unaffected.
Stability of Floating Wind Turbine Wakes Kleine, V G; Franceschini, L; Carmo, B S ...
Journal of physics. Conference series,
05/2021, Letnik:
1934, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Abstract
Floating offshore wind turbines (FOWTs) are the next frontier in offshore wind energy, allowing exploration of deep-water regions previously unavailable to fixed-foundation turbines. Since ...offshore turbines operate in lower turbulence levels, the intrinsic hydrodynamic unstable modes of the tip vortices can have even more relevance than in onshore turbines. For floating turbines, platform motion induced by wind and wave loads can trigger vortex instabilities, modifying the wake structure, possibly influencing the flow reaching downstream wind turbines. In the present paper, we study those effects by the means of numerical simulations and their comparison with analytical studies. In our simulations, the wind turbine blades are modeled as actuator lines in the incompressible Navier–Stokes equations. Heave motion with different amplitudes and frequencies are studied. The effect of increasing amplitude is to advance the onset of vortex interaction. For the lower frequency of heave motion, several vortices coalesce to form a large flow structure. High amplitude of oscillations in the streamwise velocity were observed due to these flow structures, which may increase fatigue or induce high amplitude motion on downstream turbines. The number of vortices that interact, as other qualitative phenomena of the numerical simulation, were well predicted by a simple stability model of two-dimensional row of vortices. The disturbances imposed by the heave motion were also compared to the eigenvectors resulting from linear stability theory for helical vortices and the predicted growth rates for the wavenumbers resulting from this comparison were consistent with the model of a row of vortices. These results motivate further studies to understand the impact of the larger flow structures on downstream turbines.
Summary
The association between serum uric acid (SUA) levels and bone mineral density (BMD) is controversial. Fat accumulation is linked to SUA and BMD, thus possibly explaining the mixed results. We ...found that adiposity drives part of the association between SUA and BMD in women with postmenopausal osteoporosis.
Introduction
Both positive and negative associations between SUA and BMD have been reported. SUA levels and BMD increase with higher body weight and other indices of adiposity; hence, the association between SUA and BMD might be a consequence of the confounding effect of adiposity. We investigated in this cross-sectional study whether the association between SUA and BMD is independent of measures of fat accumulation and other potential confounders.
Methods
SUA levels, femur BMD, markers of bone metabolism, body mass index (BMI), fat mass (FM), waist circumference (WC), and abdominal visceral fat area were measured in 180 treatment-naive postmenopausal osteoporotic women (mean age 66.3 ± 8.5 years, age range 48–81 years).
Results
Women with higher SUA levels (third tertile) had significantly higher femur BMD and lower cross-linked C-terminal telopeptide of type I collagen (CTX) and bone alkaline phosphatase (bALP) levels. SUA levels were positively associated with all indices of adiposity. In multivariable analysis with femur BMD as dependent variable, the association between logarithmic (LG)-transformed SUA levels and BMD (beta = 0.42,
p
< 0.001) was lessened progressively by the different indices of adiposity, like LG-BMI (beta = 0.22,
p
= 0.007), LG-WC (beta = 0.21,
p
= 0.01), LG-FM (beta = 0.18,
p
= 0.01), and LG-abdominal visceral fat area (beta = 0.12,
p
= 0.05). The association between SUA levels and markers of bone metabolism was dependent on the effect of confounders.
Conclusion
In postmenopausal osteoporotic women, the strong univariable association between SUA levels and femur BMD is partly explained by the confounding effect of indices of adiposity.
•Plasma ALP could be used as a discriminating marker in presence of bone lesions in solid tumor or MM.•Multiple Myeloma, ALP values were mainly in the range of normality than those observed in ...patients with solid cancers and bone lesions.•Lower or normal values, should suggest further investigations such as urinary and serum electrophoresis.
Bone involvement in Multiple Myeloma results from increased osteoclast formation and activity that occurs in proximity to myeloma cells. The role of Alkaline Phosphatse (ALP) in this process and the diagnostic significance of plasma levels in patients with MM are unclear.
To compare plasma ALP levels in patients with MM and solid cancers and metastatic lesions to the bone.
In this observational retrospective study we enrolled 901 patients were enrolled: 440 patients (49%) with Multiple Myeloma, 461 (51%) with solid cancers. All 901 patients had bone lesions. Among patients with Multiple Myeloma, ALP values were mainly in the range of normality than those observed in patients with solid cancers and bone lesions. This difference is independent of stage, number and type of bone lesions.
This study suggests that plasma ALP has a different clinical significance in MM than in other neoplasms and could be used as a discriminating marker in presence of bone lesions. In particular, lower or normal values, should suggest further investigations such as urinary and serum electrophoresis, associated with bone marrow aspirate in case of the presence of a monoclonal component, in order to confirm or exclude a MM diagnosis.
The present study describes Demidospermus spirophallus n. sp. and Demidospermus prolixus n. sp. (Monogenea, Dactylogyridae) from the siluriform catfish Loricaria prolixa Isbrücker & Nijssen, 1978 ...(Siluriformes, Loricariidae) from the state of São Paulo, Brazil, supported by morphological and molecular data. In addition, notes on the circumscription of the genus with a redescription of Demisdospermus anus are presented. Demidospermus spirophallus n. sp. differed from other congeners mainly because of the morphology of the male copulatory organ (MCO), which exhibited 2½ counterclockwise rings, a tubular accessory piece with one bifurcated end and a weakly sclerotized vagina with sinistral opening. Demidospermus prolixus n. sp. presents a counterclockwise-coiled MCO with 1½ rings, an ovate base, a non-articulated groove-like accessory piece serving as an MCO guide, two different hook shapes, inconspicuous tegumental annulations, a non-sclerotized vagina with sinistral opening and the absence of eyes or accessory eyespots. The present study provides, for the first time, molecular characterization data using the partial ribosomal gene (28S) of two new species of Demidospermus from Brazil (D. spirophallus n. sp. and D. prolixus n. sp.), and Demidospermus anus from Loricariichthys platymetopon Isbrücker & Nijssen, 1979 collected in the Upper Paraná River floodplain, Brazil. Additionally, a revision of the species composition of this genus and others that occur in catfish is proposed to elucidate problems with their circumscription. The Brazilian species of Demidospermus clustered together as sister taxa among Neotropical dactylogyrids from siluriforms. The morphological characterization of D. spirophallus n. sp. and D. prolixus n. sp., and the molecular data of the three species in the present study will extend knowledge about this monogenean genus from the Neotropical region, and provide new information for future phylogeny studies.
Coenzyme Q10 (CoQ10) deficiency has been associated with various clinical phenotypes, including an infantile multisystem disorder. The authors report a 33-month-old boy who presented with ...corticosteroid-resistant nephrotic syndrome in whom progressive encephalomyopathy later developed. CoQ10 was decreased both in muscle and in fibroblasts. Oral CoQ10 improved the neurologic picture but not the renal dysfunction.
Drug resistance is a major limitation for the long‐term efficacy of antiviral therapy with nucleos(t)ide analogues (NAs) in chronic hepatitis B (CHB). Antiviral resistance mutations may pre‐exist in ...the overall viral population of untreated patients. We aimed to assess the prevalence of such hepatitis B virus (HBV) variants in a large cohort of NAs‐naïve patients with CHB and to explore possible association with viral and host variables. Serum samples from 286 NAs‐naïve consecutive patients with CHB were tested for serum HBV‐DNA, and 255 of them having HBV‐DNA > 1000 IU/mL were further analysed for drug resistance mutations by INNO‐LiPA HBV DRv2/v3. NAs‐naïve patients analysed were mainly men (73%), Caucasians (85%), hepatitis B e Antigen (HBeAg) negative (79%) and genotype D (69%), with a mean age of 43.2 ± 13.4 years. HBV mutations associated with antiviral drug resistance were detected in 13 (5%) patients: three patients infected with HBV genotype C had the rtM204V + rtL180M mutations associated with lamivudine (LMV) resistance. Four patients had the rtI233V mutation that may reduce sensitivity to adefovir, and three patients had the rtM250L/V mutation typical of entecavir resistance. LMV compensatory mutations rtL80V and rtV173L were seen in two and one patients, respectively. No relationship was seen between presence of resistant or compensatory mutations and HBV‐DNA levels, HBeAg/anti‐HBe status or previous IFN therapy. These results confirm that HBV mutations, which confer resistance against currently available anti‐HBV NAs, may already exist in patients who have never received the drug.
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