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Purpose: To develop and validate a deep-learning-based algorithm (DLA) that is designed to segment and classify metallic objects in topograms of abdominal and spinal CT., Methods: DLA training for implant segmentation and classification was based on a U-net-like architecture with 263 annotated hip implant topograms and 2127 annotated spine implant topograms. The trained DLA was validated with internal and external datasets. Two radiologists independently reviewed the external dataset consisting of 2178 abdomen anteroposterior (AP) topograms and 515 spine AP and lateral topograms, all collected in a consecutive manner. Sensitivity and specificity were calculated per pixel row and per patient. Pairwise intersection over union (IoU) was also calculated between the DLA and the two radiologists., Results: The performance parameters of the DLA were consistently >95% in internal validation per pixel row and per patient. DLA can save 27.4% of reconstruction time on average in patients with metallic implants compared to the existing iMAR. The sensitivity and specificity of the DLA during external validation were greater than 90% for the detection of spine implants on three different topograms and for the detection of hip implants on abdominal AP and spinal AP topograms. The IoU was greater than 0.9 between the DLA and the radiologists. However, the DLA training could not be performed for hip implants on spine lateral topograms., Conclusions: A prototype DLA to detect metallic implants of the spine and hip on abdominal and spinal CT topograms improves the scan workflow with good performance for both spine and hip implants.

Environmental policymakers are concerned that environmental regulations reduce employment. A microeconomic analysis illustrates that environmental regulations have an uncertain effect on employment, making this an empirical question. A standard cost function model, used in the literature, requires a lot of data such as pollution abatement cost data to examine effects of environmental regulations on employment, but such survey data is not always available. In this paper, we develop a nonparametric cost function which alleviates the need for pollution abatement cost data. Our cost function, therefore, allows researchers and policy analysts to estimate employment changes associated with pollution abatement as well as measure the relative importance of other factors related to changes in employment with no pollution abatement cost data. Moreover, this is the first model using a cost function that incorporates the effect of structural change among industries within the economy on employment, which allows researchers to the examine how environmental regulations change the structure of the economy via a structural decomposition component. We illustrate how to operationalize our model using a balanced panel of industry-level data for 26 industries from 17 OECD countries (1995-2006). Our findings suggest that the change in employment due to regulatory induced increases in input costs exhibits both substantial variation among countries and substantial intra-country heterogeneity among industries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

In this study we use poly( N -isopropylacrylamide) (PNIPAM) based copolymer microgels to create free-standing, transferable, thermoresponsive membranes. The microgels are synthesized by copolymerization of NIPAM with 2-hydroxy-4-(methacryloyloxy)-benzophenone (HMABP) and spin-coated on Si wafers. After subsequent cross-linking by UV-irradiation, the formed layers easily detach from the supporting material. We obtain free standing microgel membranes with lateral extensions of several millimetres and an average layer thickness of a few hundred nanometres. They can be transferred to other substrates. As one example for potential applications we investigate the temperature dependent ion transport through the membranes via resistance measurements revealing a sharp reversible increase in resistance when the lower critical solution temperature of the copolymer microgels is reached. In addition, prior to cross-linking, the microgels can be decorated with silver nanoparticles and cross-linked afterwards. Such free-standing nanoparticle hybrid membranes are then used as catalytic systems for the reduction of 4-nitrophenol, which is monitored by UV/Vis spectroscopy., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Network models provide a general representation of inter-connected system dynamics. This ability to connect systems has led to a proliferation of network models for economic productivity analysis, primarily estimated non-parametrically using Data Envelopment Analysis (DEA). While network DEA models can be used to measure system performance, they lack a statistical framework for inference, due in part to the complex structure of network processes. We fill this gap by developing a general framework to infer the network structure in a Bayesian sense, in order to better understand the underlying relationships driving system performance. Our approach draws on recent advances in information science, machine learning and statistical inference from the physics of complex systems to estimate unobserved network linkages. To illustrate, we apply our framework to analyze the production of knowledge, via own and cross-disciplinary research, for a world-country panel of bibliometric data. We find significant interactions between related disciplinary research output, both in terms of quantity and quality. In the context of research productivity, our results on cross-disciplinary linkages could be used to better target research funding across disciplines and institutions. More generally, our framework for inferring the underlying network production technology could be applied to both public and private settings which entail spillovers, including intra- and inter-firm managerial decisions and public agency coordination. This framework also provides a systematic approach to model selection when the underlying network structure is unknown.

We study the complex mixture of a polyethylene oxide- b -polypropylene oxide- b -polyethylene oxide triblock copolymer (Pluronic F127) with ionic liquid (IL) and Li-salt, which is potentially interesting as an electrolyte system with decoupled mechanical and ion-transport properties. Small-angle X-ray scattering (SAXS) and differential scanning calorimetry (DSC) are employed to scrutinize the phase structures and elucidate the ternary phase diagram. These data are combined with the ion diffusivities obtained by pulsed field gradient (PFG) nuclear magnetic resonance (NMR). Analyzing the partial ternary phase diagram of F127/LiTFSI/Pyr 14 TFSI, hexagonal, lamellar, and micellar mesophases are identified, including two-phase coexistence regions. While the PPO block is immiscible with the liquid, and forms the backbone of the mesostructured aggregates, the PEO blocks are not well miscible with the IL. Poorly solvated, the latter may still crystallize. At a higher IL content, PEO is further solvated, but a major solvation effect occurs due to addition of Li-salt. Li ions promote solubilization of the PEO chains in the IL, since they coordinate to the PEO chains. This was identified as the mechanism of a transition of the mesostructures, with increasing Li-salt content changing from a hexagonal to a lamellar and further to a micellar phase. In summary, both, the amount of IL and its compatibility with the PEO block, the latter being controlled by the Li-salt amount, influence the compositions of the formed mesophases and the ion diffusion in their liquid regions.

In our present work we present an approach which allows one to confine proteins in structurally nearly identical bicontinuous microemulsions with systematically decreasing water domain size. It is shown that sub-diffusive behaviour occurs already at water domain sizes below 13 nm. However, above 13 nm normal diffusion is seen. Moreover, we compare protein diffusion in microemulsions to the transport of a much smaller fluorescent dye.

In the present work, we study the shear-induced transformation of polymer-rich lamellar phases into vesicles. The evolution of vesicle size is studied by different scattering techniques, rheology, and microscopy methods. The lamellar phase found in the system D 2 O/ o-xylene/ Pluronic PE9400/C 8 TAB can be fully transformed to multilamellar vesicles (MLVs) by applying shear. The size of the MLVs is proportional to the inverse square root of the shear rate. Hence, the polymer-based quaternary system behaves similar to lamellar phases based on small surfactant molecules. Additionally, we found a growth effect leading to a size increase of the vesicles after shearing was stopped.

Morgenstern et al. (2002) is well-known for its investigation of the employment effects of environmental regulations. However, the cost function specified in that paper is handicapped by its reliance on survey data of the costs of inputs assigned to pollution abatement. In this paper, we specify an input distance function that models the joint production of good and bad outputs. This allows us to measure the relative importance of factors associated with changes in employment without pollution abatement cost data. We operationalize our model using a sample of 80 coal-fired electric power plants from 1995-2005.

In this study, we have used techniques from cell biology, biochemistry, and genetics to investigate the role of the tyrosine phosphatase Shp2 in tumor cells of MMTV-PyMT mouse mammary glands. Genetic ablation or pharmacological inhibition of Shp2 induces senescence, as determined by the activation of senescence-associated β-gal (SA-β-gal), cyclin-dependent kinase inhibitor 1B (p27), p53, and histone 3 trimethylated lysine 9 (H3K9me3). Senescence induction leads to the inhibition of self-renewal of tumor cells and blockage of tumor formation and growth. A signaling cascade was identified that acts downstream of Shp2 to counter senescence: Src, focal adhesion kinase, and Map kinase inhibit senescence by activating the expression of S-phase kinase-associated protein 2 (Skp2), Aurora kinase A (Aurka), and the Notch ligand Delta-like 1 (Dll1), which block p27 and p53. Remarkably, the expression of Shp2 and of selected target genes predicts human breast cancer outcome. We conclude that therapies, which rely on senescence induction by inhibiting Shp2 or controlling its target gene products, may be useful in blocking breast cancer., (© 2015 The Authors.)

Selective inhibitors of the protein tyrosine phosphatase SHP2 (src homology region 2 domain phosphatase; PTPN11), an enzyme that is deregulated in numerous human tumors, were generated through a combination of chemical synthesis and structure-based rational design. Seventy pyridazolon-4-ylidenehydrazinyl benzenesulfonates were prepared and evaluated in enzyme assays. The binding modes of active inhibitors were simulated in silico using a newly generated crystal structure of SHP2. The most powerful compound, GS-493 (4-{(2Z)-2-[1,3-bis(4-nitrophenyl)-5-oxo-1,5-dihydro-4H-pyrazol-4-yliden]hydrazino}benzenesulfonic acid; 25) inhibited SHP2 with an IC50 value of 71±15 nM in the enzyme assay and was 29- and 45-fold more active toward SHP2 than against related SHP1 and PTP1B. In cell culture experiments compound 25 was found to block hepatocyte growth factor (HGF)-stimulated epithelial-mesenchymal transition of human pancreatic adenocarcinoma (HPAF) cells, as indicated by a decrease in the minimum neighbor distances of cells. Moreover, 25 inhibited cell colony formation in the non-small-cell lung cancer cell line LXFA 526L in soft agar. Finally, 25 was observed to inhibit tumor growth in a murine xenograft model. Therefore, the novel specific compound 25 strengthens the hypothesis that SHP2 is a relevant protein target for the inhibition of mobility and invasiveness of cancer cells., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this work, we present modeling and visualization techniques for virtual stenting of aneurysms and stenoses. In particular, contributions to support the computer-aided treatment of artery diseases - artery enlargement (aneurysm) and artery contraction (stenosis) - are made. If an intervention takes place, there are two different treatment alternatives for this kind of artery diseases: open surgery and minimally invasive (endovascular) treatment. Computer-assisted optimization of endovascular treatments is the main focus of our work. In addition to stent simulation techniques, we also present a computer-aided simulation of endoluminal catheters to support the therapy-planning phase. The stent simulation is based on a three-dimensional Active Contour Method and is applicable to both non-bifurcated (I-stents) and bifurcated stents (Y-stents). All methods are introduced in detail and are evaluated with phantom datasets as well as with real patient data from the clinical routine. Additionally, the clinical prototype that is based upon these methods is described., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Although economists have analyzed earnings, unemployment, and labor force participation for those with bipolar illness, occupational choice has yet to be explored. Psychological and medical studies often suggest an association between bipolar illness and creative achievement, but they tend to focus on eminent figures, case studies, or small samples. We seek to examine occupational creativity of non-eminent individuals with bipolar disorder. We use Epidemiologic Catchment Area data to estimate a multinomial logit model matched to an index of occupational creativity. Those with bipolar illness appear to be disproportionately concentrated in the most creative occupational category. Nonparametric kernel density estimates reveal that the densities of the occupational creativity variable for the bipolar and non-bipolar individuals significantly differ in the ECA data, and suggest that the probability of engaging in creative activities on the job is higher for bipolar than non-bipolar workers., (2010 Elsevier B.V. All rights reserved.)

The protein tyrosine phosphatase Shp2 is a positive regulator of growth factor signaling. Gain-of-function mutations in several types of leukemia define Shp2 as a bona fide oncogene. We performed a high-throughput in silico screen for small-molecular-weight compounds that bind the catalytic site of Shp2. We have identified the phenylhydrazonopyrazolone sulfonate PHPS1 as a potent and cell-permeable inhibitor, which is specific for Shp2 over the closely related tyrosine phosphatases Shp1 and PTP1B. PHPS1 inhibits Shp2-dependent cellular events such as hepatocyte growth factor/scatter factor (HGF/SF)-induced epithelial cell scattering and branching morphogenesis. PHPS1 also blocks Shp2-dependent downstream signaling, namely HGF/SF-induced sustained phosphorylation of the Erk1/2 MAP kinases and dephosphorylation of paxillin. Furthermore, PHPS1 efficiently inhibits activation of Erk1/2 by the leukemia-associated Shp2 mutant, Shp2-E76K, and blocks the anchorage-independent growth of a variety of human tumor cell lines. The PHPS compound class is therefore suitable for further development of therapeutics for the treatment of Shp2-dependent diseases.

In this chapter we propose a three-pronged approach to assessing efficiency of health care, including financial performance, performance in the production of (intermediate) medical outcomes and performance relating medical outcomes to patient health outcomes. Throughout we use frontier models which can be estimated in a number of ways, including DEA, stochastic frontiers and index numbers. We illustrate the health outcomes model with an application to cataract surgery patients in Sweden and use DEA as our estimator. Again, other frontier estimation methods as well as index numbers could be employed to explore other procedures' effectiveness and overall performance of services and/or hospitals and clinics.

In this paper, we present a fast and robust collision detection algorithm for bifurcated stent graft simulation. The algorithm is designed for simulating bifurcations of Y-stents in blood vessels in CT-data. For stent simulation, we use the active contours method (ACM) which realizes internal and external forces acting on the stent. The internal forces are for the elastic and smoothing behavior of the stent surface. The external forces (balloon force and resistance of the vessel wall) pull and push the stent towards the artery wall. In addition to these two forces, another force interacts in the bifurcated part of the stent. For this purpose, the algorithm uses axis aligned bounding boxes (AABB) that are placed along these bifurcated parts. Our simulation and collision detection algorithm is evaluated on computed tomography angiography (CTA) data with variations in anatomy and location of pathology.

In this paper, we present a novel technique of improving volume rendering quality and speed by integrating original volume data and global model information attained by segmentation. The segmentation information prevents object occlusions that may appear when volume rendering is based on local image features only. Thus the presented visualization technique provides meaningful visual results that enable a clear understanding of complex anatomical structures. In the first part, we describe a segmentation technique for extracting the region of interest based on an active contour model. In the second part, we propose a volume rendering method for visualizing the selected portions of fuzzy surfaces extracted by local image processing methods. We show the results of selective volume rendering of left and right ventricle based on cardiac datasets from clinical routines. Our method offers an accelerated technique to accurately visualize the surfaces of segmented objects.

This paper compares teaching and non-teaching hospitals in terms of their provision of patient services. We proceed by comparing the frontiers of the teaching and non-teaching hospitals using a data envelopment (DEA) type approach, which we apply to a sample of 236 teaching hospitals and 556 non-teaching hospitals operating in the US in 1994. Our results suggest that only about 10% of the teaching hospitals can effectively "compete" with non-teaching hospitals based on the provision of patient services.

Due to the development new of imaging devices which produce a large number of tomographic slices, advanced techniques for the evaluation of the large amount of data are required. Computer supported extraction of dynamic 3D-models of the patients anatomy from temporal series thus is highly desirable. Since the diagnostician should be able to quickly make sensible decisions based on the models, high accuracy is required within a minimum of time. We present modeling and visualization techniques that are realized within the Cardiac Station. Results for the application of these techniques to cardiac image data demonstrate their usability. Besides giving information about the patients morphology functional parameters can be derived from the data and visualized together with the model. In order to verify the model with the original image data and for the planning of real intervention interaction techniques are presented.

Objectives: The authors compute and compare productivity growth in the health-care sectors for a sample of Organization for Economic Cooperation and Development countries over the period from 1974 to 1989. The authors compute Malmquist productivity indexes, which allow productivity growth to be decomposed into efficiency changes and technical change. These indexes also allow the use of primary quantity data (recently available from the Organization for Economic Cooperation and Development), rather than expenditure data, which the authors argue reduces bias resulting from distorted prices., Methods: The authors specify two models. The first model focuses on the hospital sector; inputs include physicians and medical care beds, whereas outputs are the "intermediate" type used in hospital efficiency studies, namely, inpatient days and discharges., Results: For the 19 countries with complete data, the authors found little productivity growth based on this model (with the exception of Denmark, with 15.4% cumulated growth, and the United States, with about 5% from 1974 to 1989). The authors did find, however, that the highest productivity levels are found in the United States (Italy and Finland were also on the frontier of technology in the base period, 1974). The second model uses the same inputs as the first (but in per capita terms), but it specifies simple proxies of health outcomes as outputs: life expectancy of women at age 40 and the reciprocal of the infant mortality rate., Conclusions: For the 10 countries with complete data for this model, the authors found evidence of much more widespread and rapid productivity growth: Denmark's cumulated growth was close to 33%, with the United States close behind. In both these countries, this growth was due solely to technical change over this period.

In cooperation with the Max-Delbrück-Centrum/Robert-Rössle-Klinik (MDC/RRK) in Berlin, the Fraunhofer Institute for Computer Graphics is currently designing and developing a scenario for the operating room of the future. The goal of this project is to integrate new analysis, visualization and interaction tools in order to optimize and refine tumor diagnostics and therapy in combination with laser technology and remote stereoscopic video transfer. Hence, a human 3-D reference model is reconstructed using CT, MR, and anatomical cryosection images from the National Library of Medicine's Visible Human Project. Applying segmentation algorithms and surface-polygonization methods a 3-D representation is obtained. In addition, a "fly-through" the virtual patient is realized using 3-D input devices (data glove, tracking system, 6-DOF mouse). In this way, the surgeon can experience really new perspectives of the human anatomy. Moreover, using a virtual cutting plane any cut of the CT volume can be interactively placed and visualized in realtime. In conclusion, this project delivers visions for the application of effective visualization and VR systems. Commonly known as Virtual Prototyping and applied by the automotive industry long ago, this project shows, that the use of VR techniques can also prototype an operating room. After evaluating design and functionality of the virtual operating room, MDC plans to build real ORs in the near future. The use of VR techniques provides a more natural interface for the surgeon in the OR (e.g., controlling interactions by voice input). Besides preoperative planning future work will focus on supporting the surgeon in performing surgical interventions. An optimal synthesis of real and synthetic data, and the inclusion of visual, aural, and tactile senses in virtual environments can meet these requirements. This Augmented Reality could represent the environment for the surgeons of tomorrow.

In this article, we compared hospital efficiency using a multiple input-output approach in two ways: one way used a straightforward count of inpatient days and outpatient services as outputs; and the second used a case mix-adjusted count of inpatient services and outpatient care as outputs. Our results show that there was no difference when we incorporated the case-mix index, either as a weighting device or as a separate output. However, this result may be due to our having a relatively homogeneous sample, (i.e., large metropolitan hospitals). Variations using this approach may occur when using a more heterogeneous sample, such as comparing hospitals of all sizes or rural versus urban hospitals.

The association between certain lifestyle and personality characteristics and blood pressure in the elderly was assessed in a cross-sectional study of 843 independent living 60-87 year old volunteers. They comprised 338 women and 505 men of whom 35 and 30% respectively were being treated with antihypertensive drugs. Among untreated volunteers, 28% of women and 28% of men had systolic blood pressure greater than 160 or diastolic blood pressure greater than 95. Isolated systolic hypertension was found in 20% of untreated women and 14% of untreated men. Lifestyle factors and personality characteristics associated with blood pressure were similar to those described in younger adult populations, although there were some differences related to gender and whether subjects were being treated for hypertension. Stepwise multiple regression showed that higher blood pressure was associated with greater body mass index (BMI), alcohol intake and coffee drinking and measures of irritability. Increased physical activity, and high values for measures of suspicion and extraversion were negatively related to blood pressure. Age was positively related to systolic, but not to diastolic blood pressure. The presence of hypertension was significantly associated with self-reports of raised cholesterol, diabetes or angina, as well as past history of heart failure, heart attack or stroke. Thus, in this elderly free-living population blood pressures are still significantly associated with behavioural characteristics which could be further investigated as an alternative or adjunct to antihypertensive therapy.

In a study of 843 independent-living men and women aged between 60 and 87 in Perth, Western Australia, stepwise multiple regression, after correction for initial levels of systolic blood pressure, showed that postural fall in systolic blood pressure was positively related to alcohol intake of more than 20 ml/day, the use of sleeping tablets and higher levels of anxiety on the Spielberger state-trait scale, and negatively related to body mass index. Postural fall in blood pressure was not significantly related to treatment for hypertension, age, sex, patterns of usual physical activity, tea or coffee drinking, or the diagnosis of diabetes mellitus. This analysis is the first to examine the relationship between lifestyle factors and the magnitude of the fall in systolic blood pressure on standing after adjustment for the association between the change in a variable and its initial level. Our analysis suggests the need for further study of the possible role of lifestyle factors such as the use of sleeping tablets and alcohol in postural hypotension in the elderly.

In this paper a technique for assessing the relative performance of firms is introduced and applied to a sample of hospitals in California. Hospitals are compared on the basis of their relative technical efficiency. The reference technology is constructed from observed outputs and inputs (including physicians) using programming techniques, and efficiency is assessed relative to the frontier of the technology using measures similar to those suggested by Farrell. The technique used here imposes no prespecified functional form, allows for multiple outputs and inputs (allowing for differences in case mix), and yields information on the productive performance of individual hospitals. This technique can also be used to determine whether different types of hospitals use different technologies. Our results, although illustrative rather than definitive, suggest that ownership affects 'efficiency' as measured here: public and NFP hospitals have 'different' best practice frontiers, and public hospitals appear to use relatively fewer resources. These results could reflect differences in quality of care by ownership.

To assess the suitability of therapy with an angiotensin-converting enzyme inhibitor for older hypertensives, a randomised double blind two group comparison of enalapril (10 to 40 mg daily) with hydrochlorothiazide (25 to 100 mg daily) was carried out in 32 untreated and independently living subjects aged 63 to 82 years with pressures on screening greater than 100 mmHg diastolic or greater than 180 mmHg systolic and after two weeks on placebo greater than 90 mmHg diastolic or greater than 160 mmHg systolic. Twenty-five subjects completed the ten weeks of active treatment with the majority in both groups reaching target blood pressures. Four subjects on enalapril and three on hydrochlorothiazide withdrew because of side effects. Eighteen of the 32 patients volunteered troublesome symptoms they attributed to therapy, which in some instances were alleviated by reductions in drug dosage. Small but significant falls in plasma potassium and sodium and increases in plasma urea and uric acid were seen on hydrochlorothiazide only. It was concluded that although in most cases good blood pressure control can be achieved by enalapril with some advantages over other drugs in the elderly, the potential for adverse effects remains significant. Halving usual starting doses of this and other antihypertensives may help to minimise problems in older subjects.