•A method is described to assess the imperfection for structures sensitive to lateral buckling.•A simplified method for geometric nonlinear analysis of imperfect structures is described.•The ...imperfection suggested by the EN 1993-1-1 is compared with the proposal.
The purpose of this paper is to present a proposal for the design of steel structures sensitive to lateral torsional buckling due to bending moment in order to fill the gaps in the current Standard EN 1993-1-1, guidelines for obtaining the magnitude of the imperfection. The proposal generalizes the approach provided in clause 5.3.2(11) of EN 1993-1-1 for steel structures sensitive to flexural buckling under compression.
Residual venous obstruction (RVO) after deep vein thrombosis (DVT) is considered a risk factor of recurrent venous thromboembolism (VTE), arterial events and post-thrombotic syndrome (PTS). We ...hypothesized thrombo-inflammatory markers might be associated with RVO and clinical outcomes.
In a DVT cohort with routine RVO-assessment and 5-year follow-up, patients were invited for blood withdrawal after stopping anticoagulants. Thrombin generation potential, coagulation enzyme:inhibitor complexes, soluble platelet markers and clinical markers were measured in platelet-poor plasma. Associations were represented as odds ratio (OR) or hazard ratio (HR) per standard deviation.
Patients with RVO (102/306, 33 %) had higher rates of PTS (24 vs. 12 %, p = 0.008), but similar rates of recurrence (16 vs. 15 %, p = 0.91) and arterial events (7 vs. 4 %, p = 0.26). RVO was associated with thrombin peak height (OR 1.40 1.04–1.88), endogenous thrombin potential (ETP, OR 1.35 1.02–1.79), and CRP (OR 1.74 1.10–2.75). Recurrent VTE was associated with ETP (HR 1.36 1.03–1.81), FXIa:C1-inhibitor (HR 1.34 1.04–1.72), thrombin:antithrombin (HR 1.36 1.16–1.59), soluble P-selectin (HR 2.30 1.69–3.11), soluble glycoprotein VI (sGPVI, HR 1.30 1.01–1.69), D-dimer (HR 1.56 1.31–1.86), and factor VIII (HR 1.44 1.15–1.82). Arterial events were associated with sGPVI (HR 1.80 1.25–2.59). PTS was not associated with any marker.
Our findings indicate RVO was associated with thrombo-inflammation, but this did not predict clinical outcomes in this setting. Importantly, we found recurrent VTE was associated with ongoing coagulation and platelet activation in patients well beyond the acute phase of DVT. Furthermore, sGPVI indicated an increased risk of arterial events, highlighting the role of platelets in arterial thrombosis following DVT.
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•RVO was associated with TG and CRP, but not with active thrombo-inflammation.•Activated factor XI and P-selectin levels were predictive of recurrent VTE.•GPVI levels were predictive of both venous and arterial thrombotic events.
Deep vein thrombosis (DVT) is a multifactorial disease with several outcomes, but current classifications solely stratify it based on recurrence risk.
We aimed to identify DVT phenotypes and assess ...their relation to recurrent venous thromboembolism (VTE), postthrombotic syndrome, arterial events, and cancer.
Hierarchical clustering was performed on a DVT cohort with a follow-up of up to 5 years using 23 baseline characteristics. Phenotypes were summarized by discriminative characteristics. Hazard ratios (HRs) were calculated using Cox regression; the recurrence risk was adjusted for the anticoagulant therapy duration. The study was carried out in accordance with the Declaration of Helsinki and approved by the medical ethics committee.
In total, 825 patients were clustered into 4 phenotypes: 1. women using estrogen therapy (n = 112); 2. patients with a cardiovascular risk profile (n = 268); 3. patients with previous VTE (n = 128); and 4. patients without discriminant characteristics (n = 317). Overall, the risks of recurrence, postthrombotic syndrome, arterial events, and cancer were low in phenotype 1 (reference), intermediate in phenotype 4 (HR: 4.6, 1.2, 2.2, 1.8), and high in phenotypes 2 (HR: 6.1, 1.6, 4.5, 2.9) and 3 (HR: 5.7, 2.5, 2.3, 3.7).
This study identified 4 distinct phenotypes among patients with DVT that are not only associated with the increasing recurrence risk but also with outcomes beyond recurrence. Our results thereby highlight the limitations of current risk stratifications that stratify based on the predictors of the recurrence risk only. Overall, risks were lowest in women using estrogen therapy and highest in patients with a cardiovascular risk profile. These findings might inform a more personalized approach to clinical management.
•Deep vein thrombosis (DVT) is a multifactorial disease with several clinical outcomes.•Four distinct phenotypes were identified among patients with DVT using hierarchical clustering.•Distinct phenotypes were associated with different risks of clinical outcomes.•Phenotyping could inform personalized clinical management of DVT beyond recurrence.
•A procedure is described to assess the imperfection for structures.•An energy method is proposed to estimate the worst direction of the imperfection.•A simplified method for nonlinear analysis of ...imperfect structures is described.
The purpose of this paper is to present a proposal for the design of steel structures sensitive to buckling due to compression in order to fill in the gaps in the current Standard EN 1993-1-1 guidelines for obtaining the magnitude of the geometric equivalent imperfection. The proposal generalizes the approach provided in Clause 5.3.2(11) of EN 1993-1-1 (EC-3) for cases in which a torsional or flexural–torsional buckling mode may occur. The extension of the procedure also allows designers to obtain the magnitude and shape of the imperfection as well as the worst direction of the imperfection due to the external loads applied. It also identifies the cases in which it is necessary to consider the shape of the imperfection given by higher buckling modes.
•This study compared ultrasonographic to histologic small intestinal wall measurements in cats.•There was good agreement for the total wall thickness and for most layers of small intestinal ...segments.•The agreement for submucosa and muscularis measurements between both methods was poor.•Ultrasonographic intestinal wall thickness measurements may serve as reference to detect pathologies in cats.
The relationship between histological and ultrasonographic thickness of the intestinal wall and its layers in cats is unknown so far. The aims of this study were to establish the relationship between ultrasonographic measurements in the transverse and longitudinal planes of the small intestine and to establish the agreement between ultrasonographic and histologic thickness of the overall intestinal wall and layers in cat cadavers. Seventeen adult cats were euthanased for reasons unrelated to gastrointestinal tract disease and ultrasonography was performed immediately after death using a high-frequency linear transducer. Ultrasound images of the duodenum, jejunum, ileum, and distal ileum were acquired in both the longitudinal and transverse planes. Small intestinal samples were collected close to where ultrasonographic images were obtained, fixed in formalin, and histological sections were obtained. Measurements of the intestinal layers and the overall wall thickness were performed on the ultrasonographic images and histological sections.
No statistical differences were found between the ultrasonographic measurements of thickness obtained in the transverse and longitudinal planes except for the distal ileum (P<0.05). There was good agreement between the ultrasonographic and histologic measurements of the overall wall thickness and the layers of the different intestinal segments except at the submucosa and muscularis of the duodenum. Immediate postmortem ultrasonographic and histological thickness measurements of the different layers of the small intestine obtained in this study could serve as a reference for ultrasonographic scans and histological samples in cats.
Purpose
The effectiveness of exercise to lower blood pressure may depend on the type and intensity of exercise. We study the short-term (i.e., 14-h) effects of a bout of high-intensity aerobic ...interval training (HIIT) on blood pressure in metabolic syndrome (MetS) patients.
Methods
Nineteen MetS patients (55.2 ± 7.3 years, 6 women) entered the study. Eight of them were normotensive and eleven hypertensive according to MetS threshold (≥130 mmHg for SBP and/or ≥85 mmHg for DBP). In the morning of 3 separated days, they underwent a cycling exercise bout of HIIT (>90% of maximal heart rate, ~85%
V
O
2max
), or a bout of isocaloric moderate-intensity continuous training (MICT; ~70% of maximal heart rate, ~60%
V
O
2max
), or a control no-exercise trial (REST). After exercise, ambulatory blood pressure (ABP; 14 h) was monitored, while subjects continued their habitual daily activities wearing a wrist-band activity monitor.
Results
No ABP differences were found for normotensive subjects. In hypertensive subjects, systolic ABP was reduced by 6.1 ± 2.2 mmHg after HIIT compared to MICT and REST (130.8 ± 3.9 vs. 137.4 ± 5.1 and 136.4 ± 3.8 mmHg, respectively;
p
< 0.05). However, diastolic ABP was similar in all three trials (77.2 ± 2.6 vs. 78.0 ± 2.6 and 78.9 ± 2.8 mmHg, respectively). Motion analysis revealed no differences among trials during the 14-h.
Conclusion
This study suggests that the blood pressure reducing effect of a bout of exercise is influence by the intensity of exercise. A HIIT exercise bout is superior to an equivalent bout of continuous exercise when used as a non-pharmacological aid in the treatment of hypertension in MetS.
•Twenty experimental tests carried out on full-scale interior beam-column joints.•Five strengthening techniques tested to retrofit existing beam-column joints underdesigned to seismic actions.•Steel ...jacketing technique is studied as a seismic strengthening.•Test set up defined to apply both gravity and cyclic loads combination on beams.•Results are shown about ductility and strength enhancement achieved in the specimens.
This paper presents an experimental program designed to determine the behaviour of steel jacketing used as a seismic strengthening system for reinforced concrete frame structures. Tests were carried out on a total of 20 full scale interior beam-column joints. Geometry and reinforcements were selected according to existing buildings, designed solely to gravity loads under strong beam-weak column concept. Column strengthening was performed in all specimens, and four different types of column-joint connection strengthening have been tested. Two types of beam reinforcement have been included in the experimental program. Tests were carried out by subjecting specimens to gravity and cyclic loads. The paper shows general results and conclusions, describing the failure modes of the specimens. Results show that the strengthening techniques and the axial loads applied on columns can have significant influence on the seismic behaviour of the joints.
Purpose
The aim of this study was to determine the effects of high-intensity aerobic interval training (AIT) on exercise hemodynamics in metabolic syndrome (MetS) volunteers.
Methods
Thirty-eight, ...MetS participants were randomly assigned to a training (TRAIN) or to a non-training control (CONT) group. TRAIN consisted of stationary interval cycling alternating bouts at 70–90% of maximal heart rate during 45 min day
−1
for 6 months.
Results
CONT maintained baseline physical activity and no changes in cardiovascular function or MetS factors were detected. In contrast, TRAIN increased cardiorespiratory fitness (14% in
V
O
2PEAK
; 95% CI 9–18%) and improved metabolic syndrome (−42% in
Z
score; 95% CI 83–1%). After TRAIN, the workload that elicited a
V
O
2
of 1500 ml min
−1
increased 15% (95% CI 5–25%;
P
< 0.001). After TRAIN when subjects pedaled at an identical submaximal rate of oxygen consumption, cardiac output increased by 8% (95% CI 4–11%;
P
< 0.01) and stroke volume by 10% (95% CI, 6–14%;
P
< 0.005) being above the CONT group values at that time point. TRAIN reduced submaximal exercise heart rate (109 ± 15–106 ± 13 beats min
−1
;
P
< 0.05), diastolic blood pressure (83 ± 8–75 ± 8 mmHg;
P
< 0.001) and systemic vascular resistances (
P
< 0.01) below CONT values. Double product was reduced only after TRAIN (18.2 ± 3.2–17.4 ± 2.4 bt min
−1
mmHg 10
−3
;
P
< 0.05).
Conclusions
The data suggest that intense aerobic interval training improves hemodynamics during submaximal exercise in MetS patients. Specifically, it reduces diastolic blood pressure, systemic vascular resistances, and the double product. The reduction in double product, suggests decreased myocardial oxygen demands which could prevent the occurrence of adverse cardiovascular events during exercise in this population.
Clinicaltrials.gov identifier
NCT03019796.
•New test setup for headed studs installed in steel frames with reinforced concrete infill walls.•Four experimental test results under monotonic and cyclic shear loads are presented.•Experimental ...results are compared to provisions (EC-4, ACI318, AISC360) and other authors’ findings.•A reduction factor is provided for cyclic shear loads versus monotonic shear loads.
Headed studs are often used to facilitate composite actions between steel and concrete structures. In steel building structures, reinforced concrete walls are commonly used to ensure composite action to stiffen steel frames as a lateral resistance system against horizontal loads, such as earthquakes or wind. Such walls need to be anchored to the steel frame by headed studs, and these must be able to withstand shear and tension forces, as well as the interaction between these two. To design such anchors in concrete walls, it is necessary to describe experimentally their behaviour under monotonic and cyclic shear forces given that edge conditions and reinforcing details influence stud stiffness and strength.
As very few experimental studies have examined headed studs subjected to monotonic or cyclic shear with usual boundary effects in steel frames with reinforced infill walls, a new experimental test setup and test results are presented herein. Four tests on headed studs were carried out to describe the behaviour of headed studs under monotonic and cyclic shear loading, as well as to validate the new test setup.
This research shows that the behaviour of studs installed in infill walls without group effects are conservatively predicted by EC-4 and Makino’s formula under monotonic shear loading. Furthermore, a reduction factor of 0.70 is recommended to design studs subjected to cyclic shear forces.
The jigsaw of PRRSV virulence Ruedas-Torres, I.; Rodríguez-Gómez, I.M.; Sánchez-Carvajal, J.M. ...
Veterinary microbiology,
September 2021, 2021-09-00, 20210901, Letnik:
260
Journal Article
Recenzirano
Odprti dostop
•High mortality, severe clinical signs and lesions are associated with selected PRRSV strains.•Terminology used during the description of “virulent” PRRSV outbreaks is revised.•Immunopathological ...characteristics of “virulent” and classical PRRSV strains are reviewed.•An approximation to the criteria to define a “virulent” PRRSV strain is proposed.
Porcine reproductive and respiratory syndrome virus (PRRSV) is the causative agent of the, probably, most economically important disease for the pig industry worldwide. This disease, characterised by producing reproductive failure in sows and respiratory problems in growing pigs, appeared in the late 1980s in the United States and Canada. Since its appearance, strains capable of producing higher mortality rates as well as greater severity in clinical signs and lesions than classical strains have been identified. However, since the first reports of these “virulent” PRRSV outbreaks, no homogeneity and consensus in their description have been established. Moreover, to the authors’ knowledge, there is no published information related to the criteria that a PRRSV strain should fulfil to be considered as a “virulent” strain. In this review, we revise the terminology used and gather the information related to the main characteristics and differences in clinical signs, lesions, viral replication and tropism as well as immunological parameters between virulent and classical PRRSV strains and propose a first approximation to the criteria to define a virulent PRRSV strain.
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