Modelling the economic efficiency of using different strategies to control Porcine Reproductive & Respiratory Syndrome at herd level

PRRS is among the diseases with the highest economic impact in pig production worldwide. Different strategies have been developed and applied to combat PRRS at farm level. The broad variety of available intervention strategies makes it difficult to decide on the most cost-efficient strategy for a given farm situation, as it depends on many farm-individual factors like disease severity, prices or farm structure. Aim of this study was to create a simulation tool to estimate the cost-efficiency of different control strategies at individual farm level. Baseline is a model that estimates the costs of PRRS, based on changes in health and productivity, in a specific farm setting (e.g. farm type, herd size, type of batch farrowing). The model evaluates different intervention scenarios: depopulation/repopulation (D/R), close & roll-over (C&R), mass vaccination of sows (MS), mass vaccination of sows and vaccination of piglets (MS + piglets), improvements in internal biosecurity (BSM), and combinations of vaccinations with BSM. Data on improvement in health and productivity parameters for each intervention were obtained through literature review and from expert opinions. The economic efficiency of the different strategies was assessed over 5 years through investment appraisals: the resulting expected value (EV) indicated the most cost-effective strategy. Calculations were performed for 5 example scenarios with varying farm type (farrow-to-finish – breeding herd), disease severity (slightly – moderately – severely affected) and PRRSV detection (yes – no). The assumed herd size was 1000 sows with farm and price structure as commonly found in Germany. In a moderately affected (moderate deviations in health and productivity parameters from what could be expected in an average negative herd), unstable farrow-to-finish herd, the most cost-efficient strategies according to their median EV were C&R (€1′126′807) and MS + piglets (€ 1′114′649). In a slightly affected farrow-to-finish herd, no virus detected, the highest median EV was for MS + piglets (€ 721′745) and MS (€ 664′111). Results indicate that the expected benefits of interventions and the most efficient strategy depend on the individual farm situation, e.g. disease severity. The model provides new insights regarding the cost-efficiency of various PRRSV intervention strategies at farm level. It is a valuable tool for farmers and veterinarians to estimate expected economic consequences of an intervention for a specific farm setting and thus enables a better informed decision

Cost of porcine reproductive and respiratory syndrome virus at individual farm level – An economic disease model

Porcine reproductive and respiratory syndrome (PRRS) is reported to be among the diseases with the highest economic impact in modern pig production worldwide. Yet, the economic impact of the disease at farm level is not well understood as, especially in endemically infected pig herds, losses are often not obvious. It is therefore difficult for farmers and veterinarians to appraise whether control measures such as virus elimination or vaccination will be economically beneficial for their farm. Thus, aim of this study was to develop an epidemiological and economic model to determine the costs of PRRS for an individual pig farm. In a production model that simulates farm outputs, depending on farm type, farrowing rhythm or length of suckling period, an epidemiological model was integrated. In this, the impact of PRRS infection on health and productivity was estimated. Financial losses were calculated in a gross margin analysis and a partial budget analysis based on the changes in health and production parameters assumed for different PRRS disease severities. Data on the effects of endemic infection on reproductive performance, morbidity and mortality, daily weight gain, feed efficiency and treatment costs were obtained from literature and expert opinion. Nine different disease scenarios were calculated, in which a farrow-to-finish farm (1000 sows) was slightly, moderately or severely affected by PRRS, based on changes in health and production parameters, and either in breeding, in nursery and fattening or in all three stages together. Annual losses ranged from a median of € 75′724 (90% confidence interval (C.I.): € 78′885–€ 122′946), if the farm was slightly affected in nursery and fattening, to a median of € 650′090 (90% C.I. € 603′585–€ 698′379), if the farm was severely affected in all stages. Overall losses were slightly higher if breeding was affected than if nursery and fattening were affected. In a herd moderately affected in all stages, median losses in breeding were € 46′021 and € 422′387 in fattening, whereas costs were € 25′435 lower in nursery, compared with a PRRSV-negative farm. The model is a valuable decision-support tool for farmers and veterinarians if a farm is proven to be affected by PRRS (confirmed by laboratory diagnosis). The output can help to understand the need for interventions in case of significant impact on the profitability of their enterprise. The model can support veterinarians in their communication to farmers in cases where costly disease control measures are justified

Eslicarbazepine acetate as monotherapy in clinical practice: Outcomes from Euro-Esli

OBJECTIVES: To assess the effectiveness and safety/tolerability of eslicarbazepine acetate (ESL) monotherapy in clinical practice in Europe. MATERIALS AND METHODS: Euro-Esli was a pooled analysis of 14 European clinical practice studies. Responder rate (≥50% seizure frequency reduction) and seizure freedom rate (seizure freedom at least since prior visit) were assessed after 3, 6 and 12 months of ESL treatment and at last visit. Adverse events (AEs) and AEs leading to ESL discontinuation were assessed throughout follow-up. A subanalysis was conducted to assess outcomes for patients treated initially with ESL monotherapy and for patients treated at the last visit with ESL monotherapy. RESULTS: ESL was used as monotherapy in 88/2045 (4.3%) patients initially and in 229/1340 (17.1%) patients at the last visit. At 12 months, responder and seizure freedom rates were 94.1% and 88.2%, respectively, in patients treated initially with ESL monotherapy, and 93.2% and 77.4%, respectively, in patients treated at the last visit with ESL monotherapy. Corresponding values for patients treated initially with ESL adjunctive therapy were 74.8% and 39.0%, respectively; and for patients treated at the last visit with ESL adjunctive therapy, corresponding values were 70.4% and 25.9%, respectively. Safety and tolerability were generally comparable in patients treated with ESL as monotherapy or adjunctive therapy. The most commonly reported AEs (≥5% of patients in any group) were dizziness, somnolence, instability/ataxia, and fatigue. CONCLUSIONS: These clinical practice data support the use of ESL as monotherapy, as well as adjunctive therapy, for focal-onset seizures, complementing evidence from clinical trials.info:eu-repo/semantics/publishedVersio

Hypofractionated or Conventionally Fractionated Adjuvant Radiotherapy After Regional Lymph Node Dissection for High-Risk Stage III Melanoma

Aims: Adjuvant radiotherapy can be beneficial after regional lymph node dissection for high-risk stage III melanoma, as it has been shown to reduce the risk of recurrence in the node field. However, the optimal fractionation schedule is unknown and both hypofractionated and conventionally fractionated adjuvant radiotherapy are used. The present study examined the oncological outcomes of these two approaches in patients treated in an era before effective systemic immunotherapy became available. Materials and methods: This retrospective cohort study involved 335 patients with stage III melanoma who received adjuvant radiotherapy after therapeutic regional lymph node dissection for metastatic melanoma between 1990 and 2011. Information on tumour characteristics, radiotherapy doses and fractionation schedules and patient outcomes was retrieved from the institution's database and patients' medical records. Results: Hypofractionated radiotherapy (median dose 33 Gy in six fractions over 3 weeks) was given to 95 patients (28%) and conventionally fractionated radiotherapy (median dose 48 Gy in 20 fractions over 4 weeks) to 240 patients (72%). Five-year lymph node field control rates were 86.0% (95% confidence interval 78.4–94.4%) for the hypofractionated group and 85.5% (95% confidence interval 80.5–90.7%) for the conventional fractionation group (P = 0.87). There were no significant differences in recurrence-free survival (RFS) (41.7%, 95% confidence interval 32.5–53.5 versus 31.9%, 95% confidence interval 26.1–38.9; P = 0.18) or overall survival (41.2%, 95% confidence interval 32.1–52.8 versus 45.0%, 95% confidence interval 38.7–52.4; P = 0.77). On multivariate analysis, extranodal spread was associated with decreased RFS (P = 0.04) and the number of resected lymph nodes containing metastatic melanoma was associated with decreased RFS (P = 0.0006) and overall survival (P = 0.01). Conclusion: Lymph node field control rates, RFS and overall survival were similar after hypofractionated and conventionally fractionated adjuvant radiotherapy. The presence of extranodal spread and an increasing number of positive lymph nodes were predictive of an unfavourable outcome

Проблемы процесса управления в техносферной безопасности

В статье будет рассмотрены проблемы техносферной безопасности через интеграционный подход, как самый эффективный в сфере управления природопользования. Самые важные проблемы будут обобщены в вопросах государственного регулирования, также будут выявлены факторы влияния на эффективность управления данного процесса

On the complexity of computing the kk-restricted edge-connectivity of a graph

The \emph{$k$-restricted edge-connectivity} of a graph $G$, denoted by $\lambda_k(G)$, is defined as the minimum size of an edge set whose removal leaves exactly two connected components each containing at least $k$ vertices. This graph invariant, which can be seen as a generalization of a minimum edge-cut, has been extensively studied from a combinatorial point of view. However, very little is known about the complexity of computing $\lambda_k(G)$. Very recently, in the parameterized complexity community the notion of \emph{good edge separation} of a graph has been defined, which happens to be essentially the same as the $k$-restricted edge-connectivity. Motivated by the relevance of this invariant from both combinatorial and algorithmic points of view, in this article we initiate a systematic study of its computational complexity, with special emphasis on its parameterized complexity for several choices of the parameters. We provide a number of NP-hardness and W[1]-hardness results, as well as FPT-algorithms.Comment: 16 pages, 4 figure

Lipid profile with eslicarbazepine acetate and carbamazepine monotherapy in adult patients with newly diagnosed focal seizures: post hoc analysis of a phase III trial and open-label extension study

BACKGROUND: Antiseizure medications can have negative effects on plasma lipid levels. OBJECTIVES: To evaluate plasma lipid changes in patients with newly diagnosed focal epilepsy treated with eslicarbazepine acetate (ESL) or controlled-release carbamazepine (CBZ-CR) monotherapy during a phase III, randomized, double-blind (DB) trial and 2 years of ESL treatment in an open-label extension (OLE). DESIGN: Post hoc analysis of a phase III trial and OLE study. METHODS": Proportions of patients with elevated levels of total cholesterol and low-density lipoprotein (LDL) cholesterol were assessed at DB baseline, OLE baseline (last visit of DB trial), and end of OLE. RESULTS: A total of 184 patients received ESL monotherapy during the OLE: 96 received ESL monotherapy in the DB trial and 88 patients received CBZ-CR monotherapy. The proportions of patients with elevated total cholesterol and LDL cholesterol increased significantly during the DB trial in those treated with CBZ-CR monotherapy [total cholesterol, +14.9% (p < 0.001); LDL cholesterol, +11.5% (p = 0.012)] but decreased significantly after switching to ESL monotherapy in the OLE [total cholesterol, −15.3% (p = 0.008); LDL cholesterol, −11.1% (p = 0.021)]. No significant changes were observed in those treated with ESL monotherapy during the DB trial and OLE. At the end of the DB trial, between-group differences (ESL–CBZ-CR) in the proportions of patients with elevated total and LDL cholesterol were −13.6% (p = 0.037) and −12.3% (p = 0.061), respectively; at the end of the OLE, these between-group differences were −6.0% (p = 0.360) and −0.6% (p = 1.000), respectively. CONCLUSION:A lower proportion of patients with newly diagnosed focal epilepsy had increased levels of total and LDL cholesterol, compared to baseline, following monotherapy with ESL versus CBZ-CR; after switching from CBZ-CR to ESL, the proportions of patients with increased levels decreased significantly. REGISTRATION: ClinicalTrials.gov NCT01162460/NCT02484001; EudraCT 2009-011135-13/2015-001243-36

Free Rota-Baxter algebras and rooted trees

A Rota-Baxter algebra, also known as a Baxter algebra, is an algebra with a linear operator satisfying a relation, called the Rota-Baxter relation, that generalizes the integration by parts formula. Most of the studies on Rota-Baxter algebras have been for commutative algebras. Two constructions of free commutative Rota-Baxter algebras were obtained by Rota and Cartier in the 1970s and a third one by Keigher and one of the authors in the 1990s in terms of mixable shuffles. Recently, noncommutative Rota-Baxter algebras have appeared both in physics in connection with the work of Connes and Kreimer on renormalization in perturbative quantum field theory, and in mathematics related to the work of Loday and Ronco on dendriform dialgebras and trialgebras. This paper uses rooted trees and forests to give explicit constructions of free noncommutative Rota--Baxter algebras on modules and sets. This highlights the combinatorial nature of Rota--Baxter algebras and facilitates their further study. As an application, we obtain the unitarization of Rota-Baxter algebras.Comment: 23 page