Vegetation Length Research Articles

A study on the drag coefficient of emergent flexible vegetation under regular waves

The drag coefficient is a vital quantitative indicator within the field of wave attenuation by vegetation, thus receiving considerable critical attention. A systematic understanding of the drag coefficient under single flexible vegetation dynamic and emergent conditions is still insufficient. The present study aimed to quantitatively investigate the drag coefficient of emergent flexible vegetation based on a flume experiment and an emergent flexible vegetation dynamic model. Simulation results demonstrated the acceptability of constant skin friction coefficient and added mass coefficient in simulating the vegetation dynamics and determining the drag coefficient. Based on the calibration method, the obtained drag coefficients are more influenced by the Reynolds number, the Cauchy number, and the drag-to-stiffness ratio under the present investigation conditions. Vegetation flexibility can have evident influences on the drag coefficient of emergent flexible vegetation under waves. Then, a new empirical formula including the drag-to-stiffness ratio and relative vegetation length was proposed to estimate the drag coefficient. The effectiveness of the formula was demonstrated after evaluating the performance in both calculating the drag coefficient and simulating the emergent flexible vegetation dynamics. This study also provided evidence for the uncertainty in the formula establishment, and identified the uncertainty that different determination methods of characteristic wave velocity and utilizations of wave theory can lead to in the formula establishment. The findings can contribute to the understanding of the drag coefficient of emergent flexible vegetation, and highlight the potential usefulness of other parameters associated with vegetation flexibility in drag coefficient prediction.

Seasonal variations in drag coefficient of salt marsh vegetation

Understanding the seasonal variations of vegetation drag coefficients is crucial for improving wave attenuation predictions and adapting to climate impacts. This study explores the seasonal changes in drag coefficients within salt marsh vegetation, using data from a year-long series of field measurements at the Chongming Dongtan Wetland. It uncovers the complex seasonal variations of drag coefficients. Results demonstrate that incorporating a nonlinear equation for characteristic flow velocity and effective vegetation length significantly improves the precision of drag coefficient predictions, ensuring a closer match with field observations. Furthermore, it introduces a refined drag coefficient formula that incorporates adjustments for vegetation stiffness and relative submergence, offering a more accurate representation of the seasonal variability in drag forces exerted by salt marsh vegetation. This enhanced formula is crucial for accurately assessing vegetation's role in wave attenuation, providing critical insights for the design and implementation of coastal defense and wetland conservation initiatives.

Association Between Vegetation Size and Outcome in the Partial Oral Antibiotic Endocarditis Treatment Trial

Step-down oral antibiotic therapy is associated with a non-inferior long-term outcome compared with continued intravenous antibiotic therapy in the treatment of left-sided infective endocarditis. We aimed to analyze whether step-down oral therapy compared with continued intravenous antibiotic therapy is also associated with a non-inferior outcome in patients with large vegetations (vegetation length ≥ 10 mm) or among patients who underwent surgery before step-down oral therapy. We included patients without presence of aortic root abscess at diagnosis from the POET (Partial Oral Antibiotic Endocarditis Treatment) study. Multivariable Cox regression analyses were used to find associations between large vegetation, cardiac surgery, step-down oral therapy, and the primary end point (composite of all-cause mortality, unplanned cardiac surgery, embolic event, or relapse of positive blood cultures during follow-up). A total of 368 patients (age 68 ± 12, 77% men) were included. Patients with large vegetations (n = 124) were more likely to undergo surgery compared with patients with small vegetations (n = 244) (65% vs 20%, p <0.001). During a median 1,406 days of follow-up, 146 patients reached the primary end point. Large vegetations were not associated with the primary end point (hazard ratio 0.74, 95% confidence interval 0.47 to 1.18, p = 0.21). Step-down oral therapy was non-inferior to continued intravenous antibiotic in all subgroups when stratified by the presence of a large vegetation at baseline and early cardiac surgery. Step-down oral therapy is safe in the presence of a large vegetation at diagnosis and among patients who underwent early cardiac surgery.

Impact of Vegetation Length on Clinical Complications During Surgical Intervention and Long-Term Survival in Infective Endocarditis

We aimed to investigate the impact of vegetation length on clinical complications during surgical intervention and long-term survival in infective endocarditis. This was a retrospective study of patients with infective endocarditis who underwent cardiac surgery between January 2006 and November 2022 at our hospital. 896 patients were divided into 2 groups: group I (vegetation length <10mm, n=448) and group II (vegetation length≥10mm, n=448). There were 48 operative deaths (5.4%). Univariate and multivariate analyses showed that vegetation length is statistically significantly associated with destruction of the annulus (p<0.001), neurological complications before surgery (p<0.001), acute renal injury (p<0.001), prolonged intubation time (intubation time >24hours) (p<0.001), prolonged intensive care unit (ICU) retention time (ICU retention time >3days) (p<0.001), and in-hospital mortality (p<0.001), respectively. Our study showed that vegetation length is statistically significantly associated with destruction of the annulus, neurological complications before surgery, acute renal injury, prolonged intubation time, prolonged ICU retention time, in-hospital mortality, and 1-year mortality, respectively.

Natural convection due to surface cooling in sloping water bodies with vegetation

Natural convection induced by surface cooling in sloping water bodies with vegetation is investigated numerically. The sloping water body consists of a vegetated region with a bottom slope equal to 0.1 and a deep region with a horizontal bottom. The volume-averaged Navier–Stokes equations together with the volume-averaged energy equation are solved numerically in the vegetated region. Submerged vegetation has an equivalent porosity of 0.85. The vegetation length is either equal to the total or half the sloping region. A differential cooling is applied at the top free surface with a varying heat loss rate between the two regions. The non-vegetated sloping water body is also considered for validation purposes. The results indicate that, when cooling is reduced in the vegetated region (a) there is a time delay for the establishment of the quasi-steady regime and (b) the exchange flow rate and the gravity current's velocity decreases with increasing vegetation length. When cooling is completely blocked, different circulation patterns are developed.

Wave attenuation by flattened vegetation (Scirpus mariqueter)

With the capacity to reduce wave energy and trap sediment, Scirpus mariqueter has become an important native species of annual grass for ecology restoration at the Yangtze Estuary in eastern China. Due to seasonal variances of biophysical characteristics, S. mariqueter usually bends and breaks in winter, resulting in flattened stems that may reduce its wave attenuation capacity. To investigate the effects of vegetation flattening on wave attenuation, a set of flume experiments were conducted for flattened and standing vegetation under different wave conditions. The model vegetation was designed to represent the wilted S. mariqueter collected in winter with dynamic similarity. Results showed that the wave damping coefficient for flattened vegetation (βF) was 33.6%-72.4% of that for standing vegetation (βS) with the same vegetation length. Both βF and βS increased with wave height but decreased with water depth. A wave attenuation indicator (WAI) was defined to generate empirical formulas for βS and βF as well as their ratio βF/βS. The empirical formulas were then applied to modify the existing standing vegetation-based wave attenuation model for flattened vegetation and performed successfully. Understanding the wave attenuation characteristics of flattened vegetation is essential for the management of ecological restoration and coastal protection.

Correlations between the protein content in grain with economic characters in winter bread wheat breeding accessions of hybrid origin on irrigation

Purpose and Objectives. To evaluate the expression of the "protein content in grain" trait in winter bread wheat lines derived from late-ripening accessions of the Western European ecotype; to construct correlation-regression models for the relationships of the protein content in grain with the "anthesis - grain ripeness" interphase period length and grain yield in elite accessions grown in breeding nurseries.&#x0D; Material and Methods. The field studies were carried out at the Institute of Irrigated Agriculture of NAAS in 2019–2021. Modern winter wheat varieties bred at the Institute, collection specimens of the Western European ecotype, which had been introduced from France (registration numbers Kf1...16), and their hybrids were studied. Individual selections of elite plants from F2 were brought to the control nursery and evaluated for protein content in grain, yield, "anthesis - ripeness" period and other economic characteristics. Biometric measurements, biochemical analyses, and yield records were conducted by traditional methods. The study methods were field, laboratory, biochemical, breeding-genetic, and statistical. The studies were carried out under irrigation conditions at the pre-irrigation field moisture capacity (FMC) in the 0–50 cm soil layer of 75%.&#x0D; Results and Discussion. The expression of the "protein content in grain" trait in the breeding accessions selected from hybrid populations, which had been originated from Western European ecotypes of winter bread wheat, was analyzed; the correlation-regression models of the relationships between the protein content in grain, the grain yield and the "anthesis - ripeness" period were constructed. The “anthesis – ripeness” period in the best accessions lasted 45 - 52 days, and each original hybrid combination had its own optimum, which was associated with a high yield and protein content in grain. Extension of the "anthesis - ripeness" period slightly increased the grain yields of the breeding accessions from some hybrid populations; however, analogous effect on the protein content in grain was insignificant.&#x0D; Conclusions. A concurrent increase in the grain yield and protein content in grain through traditional selections is possible; however, such parallel enhancement of these traits is more suitable for heterogeneous hybrid populations with low protein contents grain and yields, or with low values of one of these traits (low protein content). For each hybrid population from parents contrasting in vegetation length, it is necessary to develop a specific plan of selections with due account for intra-population correlation-regression models of yield capacity, protein content in grain and “anthesis – ripeness” period length.

Prognostic impact of cerebral embolism in patients with active infective endocarditis and therapeutic strategies. A retrospective real world study in a surgical centre

Abstract Purpose Infective endocarditis still has high mortality and invalidating complications, such as cerebral embolism. The best strategies to prevent and to manage neurologic complications remain uncertain. This study aimed to identify predictors of septic cerebral embolism and to evaluate the role of surgery in these patients, in a real-world surgical center. Methods We retrospectively analyzed 551 consecutive patients admitted to our department with a definite diagnosis of non-device-related infective endocarditis; of these, 126 (23%) presented a neurologic complication. Results Cerebral embolism was significantly more frequent in patients with large vegetations (p=0.001), mitral valve infection (p=0.001), and Staphylococcus aureus infection (p=0.025). At multivariable analysis, only vegetation length was an independent predictor of cerebral embolism (HR 1.057, 95% CI 1.025–1.091, p 0.001), with a best predictive threshold of 10 mm at ROC curve analysis (AUC 0.54, p=0.001). Patients with neurologic complications were more often excluded from surgery despite an indication to it (16% vs 8%, p=0.001). If eligible, they were treated within two weeks from diagnosis in similar proportion as patients without cerebral embolism with similar survival rate. Predictors of mortality were hemorrhagic lesions (p=0.018), a GCS&amp;lt;14 (p=0.001) or a severe degree of disability (p=0.001) at presentation. The latter was the only independent predictor of mortality at multivariable analysis (HR 2.3, 95% CI 1.43–3.80, p=0.001). Conclusions The present study highlights the prognostic value of clinical functional presentation and the safety of cardiac surgery, when feasible, in patients with septic cerebral embolism. Funding Acknowledgement Type of funding sources: None.

Impact of septic cerebral embolism on prognosis and therapeutic strategies of infective endocarditis: a retrospective study in a surgical centre

BackgroundInfective endocarditis still has high mortality and invalidating complications, such as cerebral embolism. The best strategies to prevent and manage neurologic complications remain uncertain. This study aimed to identify predictors of cerebral septic embolism and evaluate the role of surgery in these patients in a real-world surgical centre.MethodsWe retrospectively analyzed 551 consecutive patients admitted to our department with a definite diagnosis of non-device-related infective endocarditis; of these, 126 (23%) presented a neurologic complication.ResultsCerebral embolism was significantly more frequent in patients with large vegetations (p = 0.004), mitral valve infection (p = 0.001), and Staphylococcus aureus infection (p = 0.025). At multivariable analysis, only vegetation length was an independent predictor of cerebral embolism (HR per unit 1.057, 95% CI 1.025–1.091, p 0.001), with a best predictive threshold of 10 mm at ROC curve analysis (AUC 0.54, p = 0.001). Patients with neurologic complications were more often excluded from surgery despite an indication to it (16% vs 8%, p = 0.001). If eligible, they were treated within two weeks from diagnosis in similar proportions as patients without cerebral embolism with a similar survival rate. Predictors of mortality were hemorrhagic lesions (p = 0.018), a GCS < 14 (p = 0.001) or a severe degree of disability (p = 0.001) at presentation. The latter was the only independent predictor of mortality at multivariable analysis (HR 2.3, 95% CI 1.43–3.80, p = 0.001).ConclusionsThe present study highlights the prognostic value of functional presentation and the safety of cardiac surgery, when feasible, in patients with cerebral septic embolism.

Inter-annual Changes in Runoff Quality from Green Roofs with Different Vegetation

As an important measure of the sponge city, green roofs have received extensive attention in recent years. To investigate the inter-annual changes in runoff quality of green roofs with different vegetation types, three green roofs with different vegetation cover (Sedum lineare, Portulaca grandiflora, and a non-vegetated control) were set up in Beijing. The influences of vegetation and monitoring period on runoff quality from the green roofs were evaluated using the plant growth characteristics and the quality of rainwater and runoff from the green roofs during the rainy season of 2017-2019. The results showed that all three green roofs were the sinks of NH4+-N, and the average mass concentration reduction rates were between 50.1% and 79.2%. However, all three green roofs were sources of PO43--P, DCr, DCu, and DNi. The green roofs covered with S. lineare and P. grandiflora were sinks of NO3--N in 2017, and the average mass concentration reduction rates were 71.4% and 99.5%, respectively, but they became sources of NO3--N in both 2018 and 2019. However, the non-vegetated control was the source of NO3--N in all three rainy seasons. Both vegetation type and length of monitoring period had significant effects on the mass concentrations of NO3--N, PO43--P, DNi, and DCu in runoff from the green roofs (P<0.05) but had no significant effects on the mass concentrations of NH4+-N and DCr in runoff from the green roofs (P>0.05). In 2017-2019, the mass concentrations of NO3--N in runoff from the non-vegetated control and the green roofs covered by S. lineare and the mass concentration of PO43--P in runoff from the green roof covered by P. grandiflora increased yearly. The mass concentrations of DNi and DCu in runoff from all three green roofs increased in 2018 but dropped in 2019. Among the green roofs with different vegetation types, the green roof covered by P. grandiflora showed better NO3--N retention capacity than that of the other green roofs but may have increased the concentrations of PO43--P, DNi, and DCu in the runoff.

Echocardiographic features of infective endocarditis in South Africa: A prospective cohort study

Background. Historically, infective endocarditis (IE) in South Africa (SA) was associated with the viridans group of streptococci affecting patients with underlying rheumatic heart disease (RHD). A changing IE bacteriological profile raises the question of whether the profile of underlying valvular abnormality has changed. Objectives. To investigate the prevalence of underlying structural valve abnormalities and their aetiologies associated with IE in SA, and describe the typical imaging findings. Methods. The Tygerberg Endocarditis Cohort study prospectively enrolled patients with IE between November 2019 and April 2021. Patients underwent detailed transthoracic and transoesophageal echocardiography to assess their underlying cardiac and valvular structure. Results. Among 71 patients included, a predisposing endocardial abnormality was detected in 49.3%, with RHD the most common single identifiable aetiology (16.9%). The in-hospital mortality rate was similar in patients with and without a predisposing endocardial abnormality (20% v. 16.7%; p=0.72), as was the rate of embolic events (20% v. 27.2%; p=0.58). Significantly more patients with a predisposing endocardial abnormality had an indication for surgery (94.3% v. 69.4%; p&lt;0.01). The viridans group of streptococci was more prevalent in patients with a predisposing endocardial abnormality (25.7% v. 2.7%; p&lt;0.01). Left-sided linear vegetation size &gt;10 mm was associated with an increased risk of in-hospital mortality (24% v. 5%; p=0.05). Conclusion. We observed a marked decrease in the prevalence of RHD in this cohort of patients with IE. The viridans group of streptococci was an uncommon cause of IE in patients with no predisposing endocardial abnormality detected. The presence of a predisposing endocardial abnormality was not associated with an increased risk of in-hospital mortality or embolic events. Linear vegetation length &gt;10 mm was associated with an increased risk of in-hospital mortality in patients with left-sided IE.

Infective endocarditis in octogenarians: a retrospective study in a single surgical center

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Infective endocarditis (IE) is a severe disease associated with high morbidity and mortality. The EURO-ENDO registry reported a mean age of 59.25 ± 18.03 years; 46.3% of patients were over 65 and 12.0% over 80 years. Little is known about the best management of elderly patients with IE. In these patients, surgery may be challenging. Purpose We aimed to determine the clinical and echographic characteristics, the therapeutic strategy, and the outcome of IE in octogenarians. Method We retrospectively included in the analysis 457 consecutive patients with definite active IE in a single surgical centre. Descriptive statistics are reported as mean ± standard deviation (SD) or median ± interquartile range (IQR) for continuous variables with normal and non-normal distribution and as frequencies and percentages for categorical variables. Between-groups comparisons were assessed by Student’s t-test, Mann-Whitney U test, Kruskal-Wallis, or chi-square test, as appropriate. Univariate long-term survival was analysed by the Kaplan-Meier method. Results In our cohort, octogenarians were 17% of the whole population (N = 77). In patients under the age of eighty, males were mostly involved with a sex ratio exceeding 2:1. This ratio was inverted in older people, where the female gender represented 57% of the total (0.001). Staphylococcus aureus (10.4 vs 20.5%, p =0.038) and Enterococci (29.9 vs 16.3%, p =0.008) were significantly less and more frequent than in younger people, respectively. Comorbidities were more frequent in elderly patients, such as hypertension (80.5 vs 53.2%, p = 0.001), dyslipidaemia (42.7 vs 27.3%, p = 0.008), and history of cancer (29.9 vs 19.2%, p = 0.036). Consequently, EUROSCORE II was higher (median ± IQR 19.18 ± 19.0 vs 11.9 ± 5.7, p = 0.001). In octogenarians, IE was more frequently left-sided (98.7 vs 89.2, p = 0.009) and complicated less often with peripheral embolism (31.2 vs 43.9%, p = 0.038). We found no differences between the two groups for the type of infected valve (native or prosthetic), the severity of valve dysfunction, paravalvular extension, and vegetation length. Octogenarians were more often excluded from surgery despite indication (19.5 vs 7.7%, p = 0.016) and had higher thirty-day (11.7 vs 7.9%, p = 0.001) and three-year (45 vs 30%, p = 0.001) mortality than younger patients. Conclusions Octogenarians represent a considerable proportion of overall cases of IE, with specific clinical and microbiological characteristics. Older patients are more often excluded from surgery, and the overall prognosis is poor. Abstract Figure.

Impact of early surgery in non-complicated left-sided native-valve infective endocarditis with large vegetations

The impact of early surgery for patients with left-sided native-valve infective endocarditis (LS-NV-IE) with a large vegetation (between 10 and 30 mm), free of embolic events and of other complication, has not yet been established. We aimed to describe the characteristics of these patients and to assess the impact of early surgery (≤ 7 days) in terms of 6-month outcomes. Among 1340 patients diagnosed with LS-NV-IE, 174 patients with a vegetation between 10 and 30 mm and without class I or IIa indication for surgery (according to European guidelines) were included. The primary endpoint combined death and endocarditis complications (recurrence of endocarditis, heart failure requiring hospitalization, or clinical embolic event) at 6-months. Patients( n = 42) who underwent early surgery were younger ( P = 0.019) and more likely to have a vegetation length > 15 mm (66.7%vs.47.7%) and highly mobile vegetations (59.5%vs.39.4%), than patients managed conservatively. The 6-month event-free survival was 98 ± 2% in the early surgery group and 86 ± 3% in the conservative group ( P = 0.037), even after propensity matching ( P = 0.003). On multivariable analysis, early surgery was associated with better outcome [Adjusted HR(95%CI) = 0.16(0.04–0.97); P = 0.046] ( Fig. 1 ). Early surgery for patients with LS-NV-IE and vegetation between 10 and 30 mm, free of embolic events and of other IE complication, is associated with a lower rate of events at 6 months.

Comparing the soybeans (Glycine max) vegetation length in the Polish official variety trials

AbstractOne of the best methods to achieve soybean cultivation success is to cultivate varieties with proper vegetation length. In the present work, vegetation length from a Polish soybean series of field trials conducted in years 2017–2020 was analysed using a generalized linear mixed model. It is shown that the tested varieties differ in terms of the vegetation length. In the analysed series of field trials variety, ‘Erica’ had the shortest vegetation length, whereas variety ‘Naya’ the longest. The difference in the vegetation length for these two varieties was 21 days. Moreover, by adopting two stability models to the generalized linear mixed model setting, stability of the vegetation length was studied. It is shown that variety ‘Aurelina’ was the most stable among tested varieties. Moreover, using mixed model factorial regression, it is shown that temperatures in May, June and September and total precipitation in June and August had significant influence on vegetation length in the analysed series of field trials.

Predictors of mortality in patients with right-side and cardiac device-related infective endocarditis, the esc-eorp euro-endo registry

Abstract Background/Introduction Mortality in right-sided infective endocarditis (RSIE) and cardiac device-related IE (CDRIE) rates have increased mainly due derived complications and heterogeneity of the disease. A better understanding of associated risk factors to mortality in these entities are required in order to develop an efficient therapy. Purpose The aim of this study was to assess 30-day mortality rate and variables associated in RSIE and CDRIE. Methods The ESC-EORP EURO-ENDO registry is a prospective multicenter observational study of patients presenting with definite or possible IE in Europe and ESC-affiliated/non-affiliated countries. Patients were included from January 2016 to 31 March 2018 in 156 centers from 40 countries. Clinical data, blood test analysis and multi-modality imaging tests (echocardiography, computed tomography, PET-CT, magnetic resonance) were collected. Primary endpoint was 30-day mortality. Univariable analysis was performed to assess variables associated with 30-day mortality. Results Among 269 patients with RSIE, 24 patients (9.8%) died during the first 30-day of IE diagnosis. Cut-off value for best vegetation size related to 30-day mortality was vegetation length &amp;gt;19mm, with a HR = 2.88 (95% CI 1.26–6.58, p=0.01) and a Harrell's Concordance of 0.632. Factors associated with 30-days mortality by univariable analysis were: vegetation size &amp;gt;19mm (OR = 2.99, 95% CI [1.31–6.84], p=0.009), previous stroke or transient ischemic attack (OR = 5.10, 95% CI [1.19–21.88], p=0.029), HIV infection (OR = 3.52, 95% CI [1.03–12.10], p=0.046), chronic renal failure (OR = 2.66, 95% CI [1.06–6.71], p=0.038), congestive heart failure at admission (OR = 2.34, 95% CI [1.00–5.47], p=0.050) and severe regurgitation (OR = 3.77, 95% CI [1.56–9.09], p=0.003). On the other side, among the 227 patients with CDRIE, 24 patients (8.8%) died during the first 30-day of IE diagnosis. Factors associated with an increase in 30-day mortality by univariate analysis were: age per 10 years (OR = 1.49, 95% CI [1.02–2.18], p=0.039), heart failure history (OR = 3.88, 95% CI [1.39–10.80], p=0.009), congestive heart failure on admission (OR = 5.80, 95% CI [2.31–14.55], p&amp;lt;0.001) and cardiogenic shock on admission (OR = 13.37, 95% CI [3.75–47.64], p&amp;lt;0.001). An increase in left ventricular ejection fraction (LVEF) per 10% was a protective factor (OR = 0.66, 95% CI [0.49–0.90], p=0.008). Conclusions Patients with RSIE and CDRIE had a not negligible 30-day mortality rate (9.8% and 8.8%, respectively). Factors associated with RSIE and CDRIE mortality are different; while in the right side location, the mortality was related with vegetation size and comorbidities, in the case of CDRIE, the mortality was mainly associated to the presence of heart failure. Funding Acknowledgement Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Euro-Endo registry by European Society of Cardiology

Predictors of mortality in patients with left-side infective endocarditis, the ESC-EORP EURO-ENDO registry

Abstract Background/Introduction Infective endocarditis (IE) is associated with high in-hospital mortality, ranging from 16% to 25%, despite improvement in diagnostic and therapeutic strategies, mainly due to complications and heterogeneity of the disease. Baseline risk stratification is essential, in order to focus an aggressive management toward high-risk patients. Purpose We sought to assess the association between surgery and 30-day mortality rate as related to vegetation size. Methods The ESC-EORP EURO-ENDO registry is a prospective multicentre observational study of patients presenting with definite or possible IE in Europe and ESC-affiliated/non-affiliated countries. Patients were included from January 2016 to 31 March 2018 in 156 centers from 40 countries. Clinical data, blood test analysis and multi-modality imaging tests (echocardiography, computed tomography, PET-CT, magnetic resonance) were collected. Primary endpoint was 30-day mortality. Multivariable logistic regression analysis was performed to assess variables associated with 30-day mortality. Besides, univariable analysis was performed to assess best vegetation size cut-off related to 30-day mortality. Results Among 2171 patients with left-side IE, 257 patients (11.8%) died during the first 30 days of IE diagnosis. Patient characteristics and univariable analysis are summarized in TABLE 1. Cut-off value for best vegetation size related to 30-day mortality was vegetation length &amp;gt;14mm, with a HR =2.00 (95% CI 1.59–2.51, p&amp;lt;0.0001) and a Harrell's Concordance of 0.58. After multivariable logistic regression analysis, factors associated with 30-day mortality risk were: vegetation size &amp;gt;14mm (OR =2.68, 95% CI [1.96–3.67], p&amp;lt;0.0001), previous stroke or transient ischemic attack (TIA) (OR =1.60, 95% CI [1.07–2.40], p=0.0235), creatinine &amp;gt;2mg/dL (OR =2.45, 95% CI [1.73–3.47], p&amp;lt;0.0001), presence of embolic events (OR =2.64, 95% CI [1.86–3.74], p&amp;lt;0.0001), hemorrhagic stroke (OR=3.71, 95% CI [1.80–7.64], p=0.0004), presence of heart failure or cardiogenic shock (OR =3.50, 95% CI [2.57–4.77], p&amp;lt;0.0001) and no cardiac surgery during the event (OR =4.07, 95% CI [2.93–5.67], p&amp;lt;0.0001). The C-statistic of the logistic model to predict 30-day mortality was 0.795. Conclusion Left-side infective endocarditis had a high 30-day mortality rate (11.8%). Presence of a large vegetation size (&amp;gt;14mm), embolic events, hemorrhagic stroke, renal failure, presence of heart failure or cardiogenic shock were associated with an increase in 30-day mortality. Performing cardiac surgery had a protective effect. Funding Acknowledgement Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): ESC-EORP EURO-ENDO project from the ESC society

Impact of early surgery in non-complicated left-sided native-valve infective endocarditis with large vegetations

The impact of early surgery for patients with left-sided native-valve infective endocarditis (LS-NV-IE) with a large vegetation (between 10 and 30 mm), free of embolic events and of other complication, has not yet been established. We aimed to describe the characteristics of these patients and to assess the impact of early surgery (≤ 7 days) in terms of 6-month outcomes. Among 1340 patients diagnosed with LS-NV-IE, 174 patients with a vegetation between 10 and 30 mm and without class I or IIa indication for surgery (according to European guidelines) were included. The primary endpoint combined death and endocarditis complications (recurrence of endocarditis, heart failure requiring hospitalization, or clinical embolic event) at 6-months Patients ( n = 42) who underwent early surgery were younger ( P = 0.019) and more likely to have a vegetation length > 15 mm (66.7%vs.47.7%) and highly mobile vegetations (59.5%vs.39.4%), than patients managed conservatively. The 6-month event-free survival was 98 ± 2% in the early surgery group and 86 ± 3% in the conservative group ( P = 0.037), even after propensity matching ( P = 0.003). On multivariable analysis, early surgery was associated with better outcome [Adjusted HR(95%CI) = 0.16(0.04–0.97); P = 0.046] ( Fig. 1 ). Early surgery for patients with LS-NV-IE and vegetation between 10 and 30 mm, free of embolic events and of other IE complication, is associated with a lower rate of events at 6 months.

Prognostic value of 18 F-fluorodeoxyglucose positron emission tomography/computed tomography in infective endocarditis

Abstract Funding Acknowledgements Type of funding sources: None. Background 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) is commonly used for the diagnosis of infective endocarditis (IE), but its prognostic value remains unknown. Objectives This study sought to assess the prognostic value of 18F-FDG PET/CT in prosthetic valve endocarditis (PVE) and native valve endocarditis (NVE). Methods This study prospectively included 173 consecutive patients (109 PVE and 64 NVE) with definite left-sided IE who had an 18F-FDG PET/CT and were followed-up for 1 year. The primary endpoint was a composite of major cardiac events: death, recurrence of IE, acute cardiac failure, nonscheduled hospitalization for cardiovascular indication, and new embolic event. Results 18F-FDG PET/CT was positive in 100 (58%) patients, 83% (n = 90 of 109) in the PVE, and 16% (n = 10 of 64) in the NVE group. At a mean follow-up of 225 days (interquartile range: 199 to 251 days), the primary endpoint occurred in 94 (54%) patients: 63 (58%) in the PVE group and 31 (48%) in the NVE group. In the PVE group, positive 18F-FDG PET/CT was significantly associated with a higher rate of primary endpoint (hazard ratio [HR]: 2.7; 95% confidence interval [CI]: 1.1 to 6.7; p = 0.04). Moderate to intense 18F-FDG valvular uptake was also associated with worse outcome (HR: 2.3; 95% CI: 1.3 to 4.5; p = 0.03) and to new embolic events in PVE (HR: 7.5; 95% CI: 1.24 to 45.2; p = 0.03) and in NVE (HR: 8.8; 95% CI: 1.1 to 69.5; p = 0.02). In the NVE group, 18F-FDG PET/CT was not associated with occurrence of the primary endpoint CONCLUSIONS: In addition to its good diagnostic performance, 18F-FDG PET/CT is predictive of major cardiac events in PVE and new embolic events within the first year following IE. Primary Endpoint Occurrence: Univariate and Multivariate Analysis in PVE Univariate HR (95% CI) p Value Multivariate HR (95% CI) p Value Renal insufficiency at admission 2.16 (1.00-4.68) 0.05 CRP &amp;gt;100 mg/l 2.46 (1.04-5.89) 0.02 1.90 (1.10-3.40) 0.03 Staphylococcus aureus 2.70 (1.10-6.55) 0.03 Severe valvular regurgitation 2.55 (1.01-6.41) 0.05 1.20 (0.70-2.10) 0.68 Echographic complications 1.15 (0.54-2.46) 0.72 Vegetation length &amp;gt;10 mm 2.53 (1.19-4.60) 0.03 Positive 18F-FDG PET/CT 3.74 (1.30-10.80) 0.02 2.70 (1.10-6.70) 0.04 Moderate to intense 18FDG valvular uptake 2.70 (1.20-6.30) 0.02 2.30 (1.30-4.50) 0.03 Abstract Figure.

Vegetation cover at the water surface best explains seed retention in open channels

AbstractHydrochorous dispersal through agricultural channels plays a role in structuring plant communities across agricultural landscapes. To date, research on seed retention in vegetated areas has mainly focused on vegetation types with simple architecture (often cylinders), which consequently do not represent real vegetation features. Here, we test the hypothesis that vegetation cover estimated at the water surface best explains floating seed retention in open channels. We therefore proposed an experiment to measure seed retention in a controlled environment across a large range of hydraulic conditions and vegetation architecture types. We used three types of artificial plants with contrasting morphotypes, and real seeds of Rumex crispus. Vegetation metrics were calculated on the basis of 3D plant models. We also tested the additivity of seed retention as a function of the length of vegetated area crossed by the seeds. We developed a semi‐empirical formula for predicting seed retention. The main results of the experiment show that (i) the seed retention rate reacts differently to changes in density according to species, (ii) vegetation cover at the free water surface, potentially in contact with seeds, is a generic predictor of floating seed retention whatever the nature of the vegetated cover, and (iii) 95% of seed retention was reached for a large range of surface vegetation ratios and length of vegetation cover. The proposed formula could be used by stakeholders (farmers and ecologists) to estimate the amount of vegetation needed in a channel to limit or enhance seed dispersal.

Qualification of Soybean Responses to Flooding Stress Using UAV-Based Imagery and Deep Learning.

Soybean is sensitive to flooding stress that may result in poor seed quality and significant yield reduction. Soybean production under flooding could be sustained by developing flood-tolerant cultivars through breeding programs. Conventionally, soybean tolerance to flooding in field conditions is evaluated by visually rating the shoot injury/damage due to flooding stress, which is labor-intensive and subjective to human error. Recent developments of field high-throughput phenotyping technology have shown great potential in measuring crop traits and detecting crop responses to abiotic and biotic stresses. The goal of this study was to investigate the potential in estimating flood-induced soybean injuries using UAV-based image features collected at different flight heights. The flooding injury score (FIS) of 724 soybean breeding plots was taken visually by breeders when soybean showed obvious injury symptoms. Aerial images were taken on the same day using a five-band multispectral and an infrared (IR) thermal camera at 20, 50, and 80 m above ground. Five image features, i.e., canopy temperature, normalized difference vegetation index, canopy area, width, and length, were extracted from the images at three flight heights. A deep learning model was used to classify the soybean breeding plots to five FIS ratings based on the extracted image features. Results show that the image features were significantly different at three flight heights. The best classification performance was obtained by the model developed using image features at 20 m with 0.9 for the five-level FIS. The results indicate that the proposed method is very promising in estimating FIS for soybean breeding.