Visualization of sliding and deformation of orbital fat during eye rotation

PURPOSE: Little is known about the way orbital fat slides and/or deforms during eye movements. We compared two deformation algorithms from a sequence of MRI volumes to visualize this complex behavior. METHODS: Time-dependent deformation data were derived from motion-MRI volumes using Lucas and Kanade Optical Flow (LK3D) and nonrigid registration (B-splines) deformation algorithms. We compared how these two algorithms performed regarding sliding and deformation in three critical areas: the sclera-fat interface, how the optic nerve moves through the fat, and how the fat is squeezed out under the tendon of a relaxing rectus muscle. The efficacy was validated using identified tissue markers such as the lens and blood vessels in the fat. RESULTS: Fat immediately behind the eye followed eye rotation by approximately one-half. This was best visualized using the B-splines technique as it showed less ripping of tissue and less distortion. Orbital fat flowed around the optic nerve during eye rotation. In this case, LK3D provided better visualization as it allowed orbital fat tissue to split. The resolution was insufficient to visualize fat being squeezed out between tendon and sclera. CONCLUSION: B-splines performs better in tracking structures such as the lens, while LK3D allows fat tissue to split as should happen as the optic nerve slides through the fat. Orbital fat follows eye rotation by one-half and flows around the optic nerve during eye rotation. TRANSLATIONAL RELEVANCE: Visualizing orbital fat deformation and sliding offers the opportunity to accurately locate a region of cicatrization and permit an individualized surgical plan

Intracranial actinomycosis of odontogenic origin masquerading as auto-immune orbital myositis: a fatal case and review of the literature

Background: Actinomycetes can rarely cause intracranial infection and may cause a variety of complications. We describe a fatal case of intracranial and intra-orbital actinomycosis of odontogenic origin with a unique presentation and route of dissemination. Also, we provide a review of the current literature. Case presentation: A 58-year-old man presented with diplopia and progressive pain behind his left eye. Six weeks earlier he had undergone a dental extraction, followed by clindamycin treatment for a presumed maxillary infection. The diplopia responded to steroids but recurred after cessation. The diplopia was thought to result from myositis of the left medial rectus muscle, possibly related to a defect in the lamina papyracea. During exploration there was no abnormal tissue for biopsy. The medial wall was reconstructed and the myositis responded again to steroids. Within weeks a myositis on the right side occurred, with CT evidence of muscle swelling. Several months later he presented with right hemiparesis and dysarthria. Despite treatment the patient deteriorated, developed extensive intracranial hemorrhage, and died. Autopsy showed bacterial aggregates suggestive of actinomycotic meningoencephalitis with septic thromboembolism. Retrospectively, imaging studies showed abnormalities in the left infratemporal fossa and skull base and bilateral cavernous sinus. Conclusions: In conclusion, intracranial actinomycosis is difficult to diagnose, with potentially fatal outcome. An accurate diagnosis can often only be established by means of histology and biopsy should be performed whenever feasible. This is the first report of actinomycotic orbital involvement of odontogenic origin, presenting initially as bilateral orbital myositis rather than as orbital abscess. Infection from the upper left jaw extended to the left infratemporal fossa, skull base and meninges and subsequently to the cavernous sinus and the orbits

A Review of Agent-Based Modeling of Climate-Energy Policy

Agent-based models (ABMs) have recently seen much application to the field of climate mitigation policies. They offer a more realistic description of micro behavior than traditional climate policy models by allowing for agent heterogeneity, bounded rationality and nonmarket interactions over social networks. This enables the analysis of a broader spectrum of policies. Here, we review 61 ABM studies addressing climate-energy policy aimed at emissions reduction, product and technology diffusion, and energy conservation. This covers a broad set of instruments of climate policy, ranging from carbon taxation, and emissions trading through adoption subsidies to information provision tools such as smart meters and eco-labels. Our treatment pays specific attention to behavioral assumptions and the structure of social networks. We offer suggestions for future research with ABMs to answer neglected policy questions. This article is categorized under: Climate Economics > Economics of Mitigation. © 2020 Wiley Periodicals, Inc.This study has received funding through an ERC Advanced Grant from the European Research Council (ERC) under the European Union's Horizon 2020 Research and Innovation Programme (grant agreement no. 741087). I.S. acknowledges financial support from the Russian Science Foundation [RSF grant number 19-18-00262]

Prognostic Value of Body Mass Index on Short-Term and Long-Term Outcome after Resection of Esophageal Cancer

Introduction: Cachexia and obesity have been suggested to be risk factors for postoperative complications. However, high body mass index (BMI) might result in a higher R0-resection rate because of the presence of more fatty tissue surrounding the tumor. The purpose of this study was to investigate whether BMI is of prognostic value with regard to short-term and long-term outcome in patients who undergo esophagectomy for cancer. Methods: In 556 patients who underwent esophagectomy (1991-2007), clinical and pathological outcome were compared between different BMI classes (underweight, normal weight, overweight, obesity). Results: Overall morbidity, mortality, and reoperation rate did not differ in underweight and obese patients. However, severe complications seemed to occur more often in obese patients (p = 0.06), and the risk for anastomotic leakage increased with higher BMI (12.5% in underweight patients compared with 27.6% in obese patients, p = 0.04). Histopathological assessment showed comparable pTNM stages, although an advanced pT stage was seen more often in patients with low/normal BMI (p = 0.02). A linear association between BMI and R0-resection rate was detected (p = 0.02): 60% in underweight patients compared with 81% in obese patients. However, unlike pT-stage (p < 0.001), BMI was not an independent predictor for R0 resection (p = 0.12). There was no significant difference in overall or disease-free 5-year survival between the BMI classes (p = 0.25 and p = 0.6, respectively). Conclusions: BMI is not of prognostic value with regard to short-term and long-term outcome in patients who undergo esophagectomy for cancer and is not an independent predictor for radical R0 resection. Patients oncologically eligible for esophagectomy should not be denied surgery on the basis of their BMI class

The rise of science in low-carbon energy technologies

Successfully combating climate change will require substantial technological improvements in Low-Carbon Energy Technologies (LCETs), but designing efficient allocation of R&D budgets requires a better understanding of how LCETs rely on scientific knowledge. Using data covering almost all US patents and scientific articles that are cited by them over the past two centuries, we describe the evolution of knowledge bases of ten key LCETs and show how technological interdependencies have changed over time. The composition of low-carbon energy innovations shifted over time, from Hydro and Wind energy in the 19th and early 20th century, to Nuclear fission after World War II, and more recently to Solar PV and back to Wind. In recent years, Solar PV, Nuclear fusion and Biofuels (including energy from waste) have 35–65% of their citations directed toward scientific papers, while this ratio is less than 10% for Wind, Solar thermal, Hydro, Geothermal, and Nuclear fission. Over time, the share of patents citing science and the share of citations that are to scientific papers has been increasing for all technology types. The analysis of the scientific knowledge base of each LCET reveals three fairly separate clusters, with nuclear energy technologies, Biofuels and Waste, and all the other LCETs. Our detailed description of knowledge requirements for each LCET helps to design of targeted innovation policies

Visualization of Sliding and Deformation of Orbital Fat During Eye Rotation

Citation: Hötte GJ, Schaafsma PJ, Botha CP, Wielopolski PA, Simonsz HJ. Visualization of sliding and deformation of orbital fat during eye rotation. Trans Vis Sci Tech. 2016; 5(4):9, doi:1167/tvst.5.4.9. Purpose: Little is known about the way orbital fat slides and/or deforms during eye movements. We compared two deformation algorithms from a sequence of MRI volumes to visualize this complex behavior. Methods: Time-dependent deformation data were derived from motion-MRI volumes using Lucas and Kanade Optical Flow (LK3D) and nonrigid registration (B-splines) deformation algorithms. We compared how these two algorithms performed regarding sliding and deformation in three critical areas: the sclera-fat interface, how the optic nerve moves through the fat, and how the fat is squeezed out under the tendon of a relaxing rectus muscle. The efficacy was validated using identified tissue markers such as the lens and blood vessels in the fat. Results: Fat immediately behind the eye followed eye rotation by approximately onehalf. This was best visualized using the B-splines technique as it showed less ripping of tissue and less distortion. Orbital fat flowed around the optic nerve during eye rotation. In this case, LK3D provided better visualization as it allowed orbital fat tissue to split. The resolution was insufficient to visualize fat being squeezed out between tendon and sclera. Conclusion: B-splines performs better in tracking structures such as the lens, while LK3D allows fat tissue to split as should happen as the optic nerve slides through the fat. Orbital fat follows eye rotation by one-half and flows around the optic nerve during eye rotation. Translational Relevance: Visualizing orbital fat deformation and sliding offers the opportunity to accurately locate a region of cicatrization and permit an individualized surgical plan