87 research outputs found
Growth curves of sorghum roots via quantile regression with P-splines
Plant roots are a major pool of total carbon in the planet and their dynamics
are directly relevant to greenhouse gas balance. Composted wastes are increasingly
used in agriculture for environmental and economic reasons and their role as a substitute for traditional fertilizers needs to be tested on all plant components. Here we
propose a regression quantile approach based on P-splines to assess, quantify and compare the root growth patterns in two treatment groups respectively undergoing compost and traditional fertilization
Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: An international, multicenter, comparative cohort study
PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks
Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.
PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks
Smoking, diabetes, blood hypertension: Possible etiologic role for Peyronie's disease? Analysis in 279 patients with a control group in Sicily
Objective: To assess the proportion of patients with Peyronie's Disease (PD) and the possible association with its potential risk factors in the general population of the central and western Sicily in our weekly andrological outpatient clinic. Materials and methods: We recruited a sample of 279 consecutive patients consulting our andrological outpatient clinic. Two arms were created: the first one composed by PD patients (men with symptoms suggestive for PD), the second one composed by patients with other andrological diseases (control arm). For each patient we evaluated the age, cigarette smoking, diabetes, blood hypertension and erectile function. In the PD arm we administered validated questionnaires to determine the erectile function status by the International Index of Erectile Function 5 (IIEF-5) and the pain status during erection by the Visual Analogue Scale (VAS). A univariate analysis was conducted using R software. Results: We enrolled 279 consecutive patients. The number of PD patients was 97 (34,7%). The univariate analysis showed a correlation between PD and cigarette smoking (p = 0.0242), blood hypertension (p < 0.001), erectile dysfunction (p < 0.001). No significant association was observed between diabetes and PD (p = 0.358). The median age of PD arm was 60 years and the median age of the control arm was 63,5 years; therefore the median age of PD arm resulted lower than the median age of the control arm (p = 0,031). Conclusions: Peyronie's disease is more common than we might think; furthermore it can be diagnosed among young patients. According to our results, cigarette smoking and blood hypertension may be considered statically significant risk factors for developing PD. On the contrary diabetes seems not to be a risk factor for PD. According to our results PD should be sought also in young patients. Further studies are necessary to confirm that removing the indicated risk factors may reduce the incidence of PD
Smoking, diabetes, blood hypertension: possible etiologic role for Peyronie’s disease? Analysis in 279 patients with a control group in Sicily
Objective: To assess the proportion of patients with Peyronie’s Disease (PD) and the possible association with its potential risk factors in the general population of the central and western Sicily in our weekly andrological outpatient clinic. Materials and methods: We recruited a sample of 279 consecutive patients consulting our andrological outpatient clinic. Two arms were created: the first one composed by PD patients (men with symptoms suggestive for PD), the second one composed by patients with other andrological diseases (control arm). For each patient we evaluated the age, cigarette smoking, diabetes, blood hypertension and erectile function. In the PD arm we administered validated questionnaires to determine the erectile function status by the International Index of Erectile Function 5 (IIEF-5) and the pain status during erection by the Visual Analogue Scale (VAS). A univariate analysis was conducted using R software. Results: We enrolled 279 consecutive patients. The number of PD patients was 97 (34,7%). The univariate analysis showed a correlation between PD and cigarette smoking (p = 0.0242), blood hypertension (p < 0.001), erectile dysfunction (p < 0.001). No significant association was observed between diabetes and PD (p = 0.358). The median age of PD arm was 60 years and the median age of the control arm was 63,5 years; therefore the median age of PD arm resulted lower than the median age of the control arm (p = 0,031). Conclusions: Peyronie’s disease is more common than we might think; furthermore it can be diagnosed among young patients. According to our results, cigarette smoking and blood hypertension may be considered statically significant risk factors for developing PD. On the contrary diabetes seems not to be a risk factor for PD. According to our results PD should be sought also in young patients. Further studies are necessary to confirm that removing the indicated risk factors may reduce the incidence of PD
Combining ensemble models and connectivity analyses to predict wolf expected dispersal routes through a lowland corridor.
The Italian wolf (Canis lupus italicus) population has remained isolated South of the Alps for the last few thousand years. After a strong decline, the species has recolonized the Apennines and the Western Alps, while it is currently struggling to colonize the Eastern Alps. Recently, the species was detected in a lowland park connecting the Northern Apennines to the Central Alps. If the park was able to sustain a net wolf dispersal flow, this could significantly boost the connection with the Eastern Alps and the Dinaric-Balkan population. We investigated the suitability of the park as a functional ecological corridor for the wolf through the unhospitable lowland of Northern Italy. We collected wolf occurrence data in two study areas. We modeled species distribution running a separate ensemble model for each study area and then merging the output of the models to obtain an integrated suitability map. We used this map to identify corridors for the wolf adopting a factorial least-cost path and a cumulative resistant kernel approach. The connectivity models showed that only two corridors exist in the lowland areas between the Northern Apennines and the Central Alps. The Western corridor is a blind route, while the eastern corridor passes through the park and has a continuous course. However, the models also revealed a scarce resilience of corridor connectivity in the passageways between the park and the Apennines and the Prealps, which suggests that urgent management actions are necessary to ensure the future functionality of this important corridor
Multiple smoothing parameters selection in additive regression quantiles
We propose an iterative algorithm to select the smoothing parameters in additive quantile regression, wherein the functional forms of the covariate effects are unspecified and expressed via B-spline bases with difference penalties on the spline coefficients. The proposed algorithm relies on viewing the penalized coefficients as random effects from the symmetric Laplace distribution, and it turns out to be very efficient and particularly attractive with multiple smooth terms. Through simulations we compare our proposal with some alternative approaches, including the traditional ones based on minimization of the Schwarz Information Criterion. A real-data analysis is presented to illustrate the method in practice
Multiple smoothing parameters selection in additive regression quantiles
We propose an iterative algorithm to select the smoothing parameters in
additive quantile regression, wherein the functional forms of the covariate effects are
unspecified and expressed via B-spline bases with difference penalties on the spline
coefficients. The proposed algorithm relies on viewing the penalized coeffcients as
random effects from the symmetric Laplace distribution and it turns out to be very
ecient and particularly attractive with multiple smooth terms. Through simulations
we compare our proposal with some alternative approaches, including the traditional
ones based on minimization of the Schwarz Information Criterion. A real-data analysis
is presented to illustrate the method in practice
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