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The Bat optimizing algorithm (BOA) is one of the metaheuristic algorithms and applied here to interpret self-potential (SP) data. The BOA is depending upon a bat echolocation behavior for global optimization, which the global optimum solution reached at the suggested minimum value of the objective function. The best interpretive source parameters for the subsurface structures occurred at the minimal the objective function value (global best solution). The BOA is applied to 2D SP anomaly data to estimate the characteristic source parameters (i.e., the depth to center, amplitude coefficient, origin location, geometric shape factor, and polarization and inclination angle of the causative buried structure). The BOA can be applied to single and multiple source structures in the restricted class of simple geometric shapes, which these bodies help in the validation of the subsurface ore and mineral targets. The stability and efficiency of the proposed BOA have been examined by several synthetic examples. In addition, three different real field examples from Germany and Indonesia have been successfully applied to ore and mineral investigation and geological structure studies. In general, the achieved results are in good agreement with the available borehole data and results mentioned in the literature. [ABSTRACT FROM AUTHOR]

Background: Retained rectal foreign bodies (RFBs) are uncommon clinical findings. Although the management of RFBs is rarely reported in the literature, clinicians regularly face this issue. To date, there is no standardized management of RFBs. The aim of the present study was to evaluate our own data and subsequently develop a treatment algorithm. Methods: All consecutive patients who presented between January 2006 and December 2019 with rectally inserted RFBs at the emergency department of the Klinikum Stuttgart, Germany, were retrospectively identified. Clinicopathologic features, management, complications, and outcomes were assessed. Based on this experience, a treatment algorithm was developed. Results: A total of 69 presentations with rectally inserted RFBs were documented in 57 patients. In 23/69 cases (33.3%), the RFB was removed transanally by the emergency physician either digitally (n = 14) or with the help of a rigid rectoscope (n = 8) or a colonoscope (n = 1). In 46/69 cases (66.7%), the RFB was removed in the operation theater under general anesthesia with muscle relaxation. Among these, 11/46 patients (23.9%) underwent abdominal surgery, either for manual extraction of the RFB (n = 9) or to exclude a bowel perforation (n = 2). Surgical complications occurred in 3/11 patients. One patient with rectal perforation developed pelvic sepsis and underwent abdominoperineal extirpation in the further clinical course. Conclusion: The management of RFBs can be challenging and includes a wide range of options from removal without further intervention to abdominoperineal extirpation in cases of pelvic sepsis. Whenever possible, RFBs should obligatorily be managed in specialized colorectal centers following a clear treatment algorithm. [ABSTRACT FROM AUTHOR]

Background: Early recognition and management of trauma related coagulopathy improves the outcome. Trauma facilities should implement an algorithm to identify the bleeding trauma patient with coagulopathy. Objective: The scope of the paper is to identify the indicators of early coagulopathy and to optimize the indications for thromboelastometry and coagulation support. Design: Cohort study based on data from trauma registry. Setting: Data of 493 major trauma patients treated in GH Celje from 2006 to 2014 were included into The TraumaRegister DGU (TR-DGU). Patients: Patients were selected for inclusion into TR-DGU according to the following criteria: polytraumatized patients with Injury severity score (ISS) ≥ 18, patients with injuries to single region with AIS 5, patients with major injuries to a single region and abnormal vital signs. All patients that were dead on arrival to hospital, patients presented to hospital >24 h after the injury, and head injuries that occurred with a low energy mechanism in patients on anticoagulation drugs were excluded. Measurements: Two groups were formed (with or without coagulopathy). Mortality, morbidity, length of mechanical ventilation, ICU and hospital stay were used as outcome and compared between the groups. A coagulopathy prediction model (CPM) was developed to identify the patients who were at high risk of coagulopathy. Results: Coagulopathy was present in 51 % of patients. Severe injuries to the torso and limbs, infusion of >1000 ml of fluids in the prehospital settings, and hypotension were included into CPM. If all three criteria were present, the sensitivity of the model to predict coagulopathy was 93 %. By adding the blood gas analysis (BE ≤ −5), the specificity increased to 81.7 %. Limitations: Shortcomings of our analysis are mainly related to the quality of data in the registry that may not be comparable to a clinical trial where data are collected specifically to address a given issue. Conclusions: The Criteria for activation of coagulation support treatment remain centre dependent. In our settings the CPM is the tool to select patients for ROTEM analysis. By adding data from blood gas analysis, treatment of coagulopathy is justifiable before complete test results are available. [ABSTRACT FROM AUTHOR]

This paper introduces an approach for generating scenarios of sea port container terminals. The scenarios can be used as input data for simulation models. Furthermore, they can be employed as test data for algorithms to solve optimization problems in container terminal logistics such as berth planning and crane scheduling. A scenario consists of arrivals of deep sea vessels, feeder ships, trains, and trucks together with lists of containers to be loaded and unloaded. Moreover, container attributes such as size, empty, reefer, weight. and destination are included. The generator is based on a large number of parameters that allow the user to produce realistic scenarios of any size. The purpose of this paper is to outline the parameters that are important to produce realistic scenarios of high practical relevance and to propose an algorithm that computes scenarios on the basis of these parameters. The generator discussed here has been developed within the simulation project at the HHLA Container-Terminal Altenwerder in Hamburg, Germany. Nevertheless, its structure is general enough to be applied to any other terminal as well. [ABSTRACT FROM AUTHOR]

Objectives: Treatment switching adjustment methods are often used to adjust for switching in oncology randomized controlled trials (RCTs). In this exploratory analysis, we apply these methods to adjust for treatment changes in the setting of an RCT followed by an extension study in relapsing-remitting multiple sclerosis.Methods: The CLARITY trial evaluated cladribine tablets versus placebo over 96 weeks. In the 96-week CLARITY Extension, patients who received placebo in CLARITY received cladribine tablets; patients who received cladribine tablets in CLARITY were re-randomized to placebo or cladribine tablets. End points were time to first qualifying relapse (FQR) and time to 3- and 6-month confirmed disability progression (3mCDP, 6mCDP). We aimed to compare the effectiveness of cladribine tablets with placebo over CLARITY and the extension. The rank-preserving structural failure time model (RPSFTM) and iterative parameter estimation (IPE) were used to estimate what would have happened if patients had received placebo in CLARITY and the extension versus patients that received cladribine tablets and switched to placebo. To gauge whether treatment effect waned after the 96 weeks of CLARITY, we compared hazard ratios (HRs) from the adjustment analysis with HRs from CLARITY.Results: The RPSFTM resulted in an HR of 0.48 [95% confidence interval (CI) 0.36-0.62] for FQR, 0.62 (95% CI 0.46-0.84) for 3mCDP and 0.62 (95% CI 0.44-0.88) for 6mCDP. IPE algorithm results were similar. CLARITY HRs were 0.44 (95% CI 0.34-0.58), 0.60 (95% CI 0.41-0.87) and 0.58 (95% CI 0.40-0.83) for FQR, 3mCDP and 6mCDP, respectively.Conclusions: Treatment switching adjustment methods are applicable in non-oncology settings. Adjusted CLARITY plus CLARITY Extension HRs were similar to the CLARITY HRs, demonstrating significant treatment benefits associated with cladribine tablets versus placebo.Funding: EMD Serono, Inc. (a business of Merck KGaA, Darmstadt, Germany). [ABSTRACT FROM AUTHOR]

In this paper we investigate a vehicle routing problem motivated by a real-world application in cooperation with the German Automobile Association (ADAC). The general task is to assign service requests to service units and to plan tours for the units such as to minimize the overall cost. The characteristics of this large-scale problem due to the data volume involve strict real-time requirements. We show that the problem of finding a feasible dispatch for service units starting at their current position and serving at most k requests is NP-complete for each fixed k ≥ 2. We also present a polynomial time (2 k − 1)-approximation algorithm, where again k denotes the maximal number of requests served by a single service unit. For the boundary case when k equals the total number | E| of requests (and thus there are no limitations on the tour length), we provide a $${\left(2-\frac{1}{|E|} \right)}$$ -approximation. Finally, we extend our approximation results to include linear and quadratic lateness costs. [ABSTRACT FROM AUTHOR]

This paper illustrates a method based on local likelihood (LL) for detecting disease clusters. The approach is based on estimating a lasso distance for each region: within which regions are considered to be clustered. An important advantage in implementing this approach is that it does not require any special Monte Carlo Markov Chain (MCMC) algorithm, e.g., reversible jump MCMC, which is essential in hidden Markov model approach. Another advantage is that extending the model to incorporate covariates is straightforward. We illustrate three ways of doing this by using Eastern Germany lip cancer data. By using simulated data, we have made a comparison with the BYM model [Besag et al. (1991) Annals of the Institute of Statistical Mathematics, 43, 1–59] and the mixture model [Lawson and Clark (2002) Disease Mapping and Risk Assessment for Public Health, Chapman and Hall]. We also did a limited examination of the ability of the LL model to recover true relative risk under different priors for lasso parameter. In order to check the edge effects, which has been overlooked in many spatial clustering models for disease mapping but deserves special attention as it lacks observable neighbors, we have adapted here a simple approach to observe the changes in relative risks when the edge regions are omitted. [ABSTRACT FROM AUTHOR]

The management of moving objects has been intensively studied in recent years. A wide and increasing range of database applications has to deal with spatial objects whose position changes continuously over time, called moving objects. The main interest of these applications is to efficiently store and query the positions of these continuously moving objects. To achieve this goal, index structures are required. The main proposals of index structures for moving objects deal with unconstrained 2-dimensional movement. Constrained movement is a special and a very important case of object movement. For example, cars move in roads and trains in railroads. In this paper we propose a new index structure for moving objects on networks, the MON-Tree. We describe two network models that can be indexed by the MON-Tree. The first model is edge oriented, i.e., the network consists of nodes and edges and there is a polyline associated to each edge. The second one is more suitable for transportation networks and is route oriented, i.e., the network consists of routes and junctions. In this model, a polyline also serves as a representation of the routes. We propose the index in terms of the basic algorithms for insertion and querying. We test our proposal in an extensive experimental evaluation with generated data sets using as underlying networks the roads of Germany. In our tests, the MON-Tree shows good scalabiliy and outperforms the competing index structures in updating (index creation) as well as in querying. [ABSTRACT FROM AUTHOR]

Objective: Our aim was to determine the prevalence of tuberculosis (TB), the number needed to screen (NNS), and the diagnostic accuracy of chest X-ray (CXR) screening to detect active pulmonary TB during the 2015 European refugee crisis.Materials and Methods: We evaluated data of all refugees who underwent CXR screening in a single-centre of one German metropolitan area in 2015. We determined the prevalence of TB, NNS, and accuracy of CXR to detect active pulmonary TB. Reference method for active TB was the database of all definite TB cases registered at the Department of Public Health.Results: A total of 17,487 immigrants underwent single-centre CXR screening in 2015; prevalence of definite pulmonary TB was 0.103%. The NNS for detecting one case of active pulmonary TB was 1749. CXR had a sensitivity of 55.6% [95% confidence interval (CI) 30.8-78.5%) and a specificity 98.3% (CI 98.1-98.5%) to reveal one case of active TB.Conclusion: Our single-centre study indicates that chest X-ray screening for TB during the 2015 European refugee crisis was of low yield due the low prevalence of TB and high number needed to screen, thus implicating the need for improved screening algorithms adapted to the overwhelming number of refugees.Key Points: • Prevalence of pulmonary tuberculosis (TB) among refugees in 2015 was low (0.103%). • The number needed to screen to detect one case of active pulmonary TB was 1749. • Tuberculosis X-ray screening resulted in a low sensitivity and high specificity. • Tuberculosis X-ray screening during the European refugee crisis is of low yield. • Improved screening algorithms are needed due to the overwhelming the number of refugees. [ABSTRACT FROM AUTHOR]

The article focuses on a study which examines large-scale observational evidence of cross-cultural differences in facial behavior using advanced in computer science. Topics discussed include the automated facial coding used, the reliability of the facial action unit detection algorithms across different testing subsets, multilevel regression estimates predicting each facial action's base rate percentage.

Introduction: The prevalence of osteoporosis in female patients over 75 years of age is 59.2 %. In Germany ~6.3-7.8 million patients are affected by osteoporosis. In 77 % of german patients osteoporosis is not treated adequately. Even after fragility fractures only 16-21 % of female patients and 3 % of male patients are supplied with a specific osteoporosis therapy. Establishing a Fracture Liaison Services (FLS) is a possible addition to co-management for an efficient treatment of osteoporosis in orthogeriatric patients. Materials and methods: According to a treatment algorithm adapted to the DVO guideline 2014, data of 251 (77 male, 173 female) patients were collected over 3 months. For the assessment specific and standardized questionnaires were used. There was also a basic laboratory testing for osteoporosis done. Results: The average age of female patients was 76.1 years, in male patients 76.6 years. Thirty-seven patients had vertebral fractures, 25 patients proximal humerus fractures, 18 distal radius fractures and a total of 78 proximal femur fractures were recorded. Eighteen percent of the 251 patients have already been treated with a basic and 11 % with a specific osteoporosis medication. Approximately 40 % of the orthogeriatric patients were diagnosed with osteoporosis for the first time in our clinic. Less than 1 % of the patients had a vitamin D level over 40 ng/ml and 32 % had a vitamin D level under 10 ng/ml. Sixty-five percent of the discharged patients received a basic osteoporosis therapy and 25 % an additional specific therapy. Discussion: Due to the demographic development osteoporosis-associated fractures steadily increase. In addition to the surgical treatment of fractures, osteological diagnosis and treatment are essential components of successful treatment and critical to the prevention of further fractures. A combination of orthogeriatric center and fracture liaison service allows a more efficient treatment of osteoporosis by close supervision of orthogeriatric patients by the physicians involved. [ABSTRACT FROM AUTHOR]

To reduce phenotypic heterogeneity of Autism spectrum disorders (ASD) and add to the current diagnostic discussion this study aimed at identifying clinically meaningful ASD subgroups. Cluster analyses were used to describe empirically derived groups based on the Autism Diagnostic Interview-revised (ADI-R) in a large sample of n = 463 individuals with ASD aged 3-21. Three clusters were observed. Most severely affected individuals regarding all core symptoms were allocated to cluster 2. Cluster 3 comprised moderate symptom severity of social communication impairments (SCI) and less stereotyped repetitive behavior (RRB). Minor SCI and relatively more RRB characterized cluster 1. This study offers support for both, a symptom profile, and a gradient model of ASD within the spectrum due to the sample included. [ABSTRACT FROM AUTHOR]

A widely discussed shortcoming of long-term care in nursing homes for the elderly is the inappropriate or suboptimal drug utilization, particularly of psychotropic drugs. Using administrative data from the largest sickness fund in Germany, this study was designed to estimate the effect of institutionalization on the drug intake of the frail elderly. Difference-in-differences propensity score matching techniques were used to compare drug prescriptions for the frail elderly who entered a nursing home with those who remained in the outpatient care system; findings suggest that nursing home residents receive more doses of antipsychotics, antidepressants, and analgesics. The potential overprescription correlates with estimated drug costs of about €87 million per year. [ABSTRACT FROM AUTHOR]

The article discusses a study whose objectives include establishing an electronic transfer of radiological images (DICOM) between hospitals with heterogeneous software and hardware equipment, examining the speed and volume of typical transfers and analyzing how the transfer volume can be decreased by various compression algorithms. It notes that the typical bandwidth of a normal DSL-connection is enough to transmit typical volume of a trauma patient within an acceptable time.

Purpose: This comparative study examines the categorisation of patients undergoing surgical repair of inguinal hernia in the diagnosis-related group (DRG) systems of 11 European countries (Austria, England, Estonia, Finland, France, Germany, Ireland, the Netherlands, Poland, Spain and Sweden). Understanding the design and operation of DRG systems for this common surgical procedure is important, given their increasing use internationally for hospital reimbursement and performance measurement. Methods: A common definition was used to identify inguinal hernia patients and the corresponding data were extracted from national databases. The analysis compared the variables and algorithms for classifying these patients to DRGs across the participating countries, as well as the number, composition and relative resource intensity of groups. An index case and six standardised vignettes were grouped using each country's DRG system and the associated quasi-prices were calculated. Results: The number of groups to which inguinal hernia patients are assigned is typically three or four, but ranges from two in Poland to ten in France. In most systems, categorising patients is contingent on procedure, principal and secondary diagnoses, and age, with treatment setting (day case/inpatient) being less common. Added to these, the French system also incorporates length of stay and whether the patient died. More resource intensive DRGs generally contained patients who were older, treated as inpatients, did not die, had (more severe) complications and/or co-morbidities, and/or underwent laparoscopic repair. There are cross-country disparities in day case rates and the use of laparoscopic repairs. Conclusions: The categorisation of inguinal hernia patients varies across the 11 European DRG systems under study. By highlighting the main differences across these systems, this comparative analysis allows the relevant decision makers to assess the adequacy and specificity of their own DRG systems. [ABSTRACT FROM AUTHOR]

This prospective observational study evaluates the validity of an algorithm for assigning patients to a multidisciplinary modularized managed care headache treatment program. N = 545 chronic headache sufferers [migraine (53.8 %), migraine + tension type (30.1 %), tension type (8.3 %) or medication overuse headache (6.2 %), other primary headaches (1.5 %)] were assigned to one of four treatment modules differing with regard to the number and types of interventions entailed (e.g., medication, psychological intervention, physical therapy, etc.). A rather simple assignment algorithm based on headache frequency, medication use and psychiatric comorbidity was used. Patients in the different modules were compared with regard to the experienced burden of disease. 1-year follow-up outcome data are reported ( N = 160). Headache frequency and analgesic consumption differed significantly among patients in the modules. Headache-related disability was highest in patients with high headache frequency with/without medication overuse or psychiatric comorbidity (modules 2/3) compared to patients with low headache frequency and medication (module 0). Physical functioning was lowest in patients with chronic headache regardless of additional problems (modules 1/2/3). Psychological functioning was lowest in patients with severe chronicity with/without additional problems (module 2/3) compared to headache suffers with no/moderate chronicity (module 0/1). Anxiety or depression was highest in patients with severe chronicity. In 1-year follow-up, headache frequency (minus 45.3 %), consumption of attack-aborting drugs (minus 71.4 %) and headache-related disability decreased (minus 35.9 %). Our results demonstrate the clinical effectiveness and the criterion validity of the treatment assignment algorithm based on headache frequency, medication use and psychiatric comorbidity. [ABSTRACT FROM AUTHOR]

Existing simple but theoretically based clear-sky models for longwave down-welling radiation (LDR) and cloud impact algorithms transforming them to all-sky radiation (LDR) are checked against locally calibrated empirical algorithms. They are evaluated for daylight hours based on measurements in regionally differing climates of Germany. The Prata clear-sky scheme is additionally tested with adjusted coefficients so that LDR converges against a realistic emissivity for a completely dry atmosphere. This version is characterised by an improved modelled variance. Compared with locally calibrated schemes, bias and root mean square error (RMSE) of the more theoretical clear-sky schemes do not differ significantly and yield even better results at a mountain site. In contrast, the locally calibrated algorithms yield biases up to 9% and an increase in RMSE between 6% and 67%, if applied for other sites. For daylight hours, the cloud impact on LDR can be calculated via the ratio of observed to clear-sky global irradiation (CMF). With CMF, the Crawford and Duchon scheme reveals the lowest bias and a decrease in RMSE by 22% against the next best performing algorithms. Compared with synoptic cloud observations as input, the bias is reduced by 9 to 28 W m and the scattering of the residuals decreases by 20% to 30%. Based on published results for also non-European sites, it is inferred that the more theoretically based LDR schemes and cloud impact evaluated via CMF are universally applicable and perform at least in the order of magnitude of locally calibrated empirical algorithms. [ABSTRACT FROM AUTHOR]

We discuss the clustering of 234 environmental samples resulting from an extensive monitoring program concerning soil lead content, plant lead content, traffic density, and distance from the road at different sampling locations in former East Germany. Considering the structure of data and the unsatisfactory results obtained applying classical clustering and principal component analysis, it appeared evident that fuzzy clustering could be one of the best solutions. In the following order we used different fuzzy clustering algorithms, namely, the fuzzy c-means (FCM) algorithm, the Gustafson–Kessel (GK) algorithm, which may detect clusters of ellipsoidal shapes in data by introducing an adaptive distance norm for each cluster, and the fuzzy c-varieties (FCV) algorithm, which was developed for recognition of r-dimensional linear varieties in high-dimensional data (lines, planes or hyperplanes). Fuzzy clustering with convex combination of point prototypes and different multidimensional linear prototypes is also discussed and applied for the first time in analytical chemistry (environmetrics). The results obtained in this study show the advantages of the FCV and GK algorithms over the FCM algorithm. The performance of each algorithm is illustrated by graphs and evaluated by the values of some conventional cluster validity indices. The values of the validity indices are in very good agreement with the quality of the clustering results. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The article discusses the highlights of the 5th Cologne-Twente Workshop on Graphs and Combinatorial Optimization (CTW 2006) held in Lambrecht, Germany on June 5-9, 2006. Partners involved in the annual CTW event include the Politechnico di Milano, the University of Duisberg-Essen and the Universit&aagrave; degli Studi di Milano. Some of the topics discussed at the workshop were graph theory, discrete algorithms, and combinatorial optimization. It also addressed the Hamiltonian circuit problem.