Penalties and Optimality in Financial Contracts: Taking Stock

A popular view of limited liability in financial contracting is that it is the result of societal preferences against excessive penalties. The view of most financial economists is instead that limited liability emerged as an optimal institution when, in the absence of a clear limit on economic agents liability, the development of some economic activities might have been thwarted. Viewing the institution from the perspective of optimal legal system design allows us to better understand the current debate on it. We present a broad history of penalties in financial contracts to highlight the interactions between technology, legal environments, purpose of the financial relationship, and contractual provisions. We show that harsh monetary and non-pecuniary penalties are not mere relics from a bygone era and, at the same time, that limited liability is far from a recent institution. We then discuss trade-offs associated with legal mandates of either unlimited or limited liability, both for the contracting parties and for the rest of Society. We identify two broad patterns. First, the toughness of liability rules and bankruptcy laws decreases as exogenous sources of uncertainty become relatively more important, and increases with the opportunity for moral hazard (related to diligence, risk taking, or deception). Second, bankruptcy laws become more lenient as the scope for labor specialization and the returns to human capital or entrepreneurship increase.Limited Liability, Bankruptcy, Debt Bondage, Debtors' Prison, History

Serial FEM/XFEM-Based Update of Preoperative Brain Images Using Intraoperative MRI

Current neuronavigation systems cannot adapt to changing intraoperative conditions over time. To overcome this limitation, we present an experimental end-to-end system capable of updating 3D preoperative images in the presence of brain shift and successive resections. The heart of our system is a nonrigid registration technique using a biomechanical model, driven by the deformations of key surfaces tracked in successive intraoperative images. The biomechanical model is deformed using FEM or XFEM, depending on the type of deformation under consideration, namely, brain shift or resection. We describe the operation of our system on two patient cases, each comprising five intraoperative MR images, and we demonstrate that our approach significantly improves the alignment of nonrigidly registered images

Preserving the ability to discriminate between left and right; A case study

Left-right orientation, a function related to the parietal lobe, is important for many daily activities. Here, we describe a left-handed patient with a right parietal brain tumour. During awake surgery, electric stimulation of the right inferior parietal lobe resulted in mistakes in his left-right orientation. Postoperatively our patient had no problems in discriminating left right. This case report shows that monitoring of left-right orientation during awake brain tumour surgery is feasible so that this function can be preserved

Preserving the ability to discriminate between left and right; A case study

Left-right orientation, a function related to the parietal lobe, is important for many daily activities. Here, we describe a left-handed patient with a right parietal brain tumour. During awake surgery, electric stimulation of the right inferior parietal lobe resulted in mistakes in his left-right orientation. Postoperatively our patient had no problems in discriminating left right. This case report shows that monitoring of left-right orientation during awake brain tumour surgery is feasible so that this function can be preserved

Cosmetic satisfaction and patient-reported outcome measures following cranioplasty after craniectomy - A prospective cohort study

INTRODUCTION: Evaluating patient-reported outcomes (PROMs) helps optimize preoperative counseling and psychosocial care for patients who underwent cranioplasty. RESEARCH QUESTION: This study aimed to evaluate cosmetic satisfaction, level of self-esteem, and fear of negative evaluation (FNE) of patients who underwent cranioplasty. MATERIAL AND METHODS: Patients who underwent cranioplasty from 1 January 2014 to 31 December 2020 ​at University Medical Center Utrecht and a control group consisting of our center' employees were invited to fill out the Craniofacial Surgery Outcomes Questionnaire (CSO-Q), consisting of an assessment of cosmetic satisfaction, the Rosenberg Self-Esteem Scale (RSES), and the FNE scale. To test for differences in results, chi-square tests and T-tests were performed. Logistic regression was used to study the effect of cranioplasty-related variables on cosmetic satisfaction. RESULTS: Cosmetic satisfaction was seen in 44/80 patients (55.0%) and 52/70 controls (74.3%) (p ​= ​0.247). Thirteen patients (16.3%) and 8 controls (11.4%) had high self-esteem (p ​= ​0.362), 51 patients (63.8%) and 59 controls (84.3%) had normal self-esteem (p ​= ​0.114), and 7 patients (8.8%) and 3 controls (4.3%) had low self-esteem (p ​= ​0.337). Forty-nine patients (61.3%) and 39 controls (55.7%) had low FNE (p ​= ​0.012), 8 patients (10.0%) and 18 controls (25.7%) had average FNE (p ​= ​0.095), and 6 patients (7.5%) and 13 controls (18.6%) had high FNE (p ​= ​0.215). Cosmetic satisfaction was associated with glass fiber-reinforced composite implants (OR 8.20, p-value ​= ​0.04). DISCUSSION AND CONCLUSION: This study prospectively evaluated PROMs following cranioplasty, for which we found favorable results

Development of a Prediction Model for Cranioplasty Implant Survival Following Craniectomy

BACKGROUND: Cranioplasty after craniectomy can result in high rates of postoperative complications. Although determinants of postoperative outcomes have been identified, a prediction model for predicting cranioplasty implant survival does not exist. Thus, we sought to develop a prediction model for cranioplasty implant survival after craniectomy. METHODS: We performed a retrospective cohort study of patients who underwent cranioplasty following craniectomy between 2014 and 2020. Missing data were imputed using multiple imputation. For model development, multivariable Cox proportional hazards regression analysis was performed. To test whether candidate determinants contributed to the model, we performed backward selection using the Akaike information criterion. We corrected for overfitting using bootstrapping techniques. The performance of the model was assessed using discrimination and calibration. RESULTS: A total of 182 patients were included (mean age, 43.0 ± 19.7 years). Independent determinants of cranioplasty implant survival included the indication for craniectomy (compared with trauma-vascular disease: hazard ratio [HR], 0.65 [95% confidence interval (CI), 0.36-1.17]; infection: HR, 0.76 [95% CI, 0.32-1.80]; tumor: HR, 1.40 [95% CI, 0.29-6.79]), cranial defect size (HR, 1.01 per cm 2 [95% CI, 0.73-1.38]), use of an autologous bone flap (HR, 1.63 [95% CI, 0.82-3.24]), and skin closure using staples (HR, 1.42 [95% CI, 0.79-2.56]). The concordance index of the model was 0.60 (95% CI, 0.47-0.73). CONCLUSIONS: We have developed the first prediction model for cranioplasty implant survival after craniectomy. The findings from our study require external validation and deserve further exploration in future studies

GFAP Alternative Splicing and the Relevance for Disease - A Focus on Diffuse Gliomas

Glial fibrillary acidic protein (GFAP) is an intermediate filament protein that is characteristic for astrocytes and neural stem cells, and their malignant analogues in glioma. Since the discovery of the protein 50 years ago, multiple alternative splice variants of the GFAP gene have been discovered, leading to different GFAP isoforms. In this review, we will describe GFAP isoform expression from gene to protein to network, taking the canonical isoforms GFAPα and the main alternative variant GFAPδ as the starting point. We will discuss the relevance of studying GFAP and its isoforms in disease, with a specific focus on diffuse gliomas

A STAT3 Gene Expression Signature in Gliomas is Associated with a Poor Prognosis

Gliomas frequently display constitutive activation of the transcription factor STAT3, a protein that is known to be able to mediate neoplastic transformation. STAT3 regulates genes that play a central role in cellular survival, proliferation, self-renewal, and invasion, and a cohort of STAT3 target genes have been found that are commonly coexpressed in human cancers. Thus, these genes likely subserve the transforming ability of constitutively activated STAT3. To determine whether the coordinated expression of STAT3 target genes is present in a subset of human gliomas, and whether this changes the biology of these tumors in patients, gene expression analysis was performed in four distinct human glioma data sets for which patient survival information was available. Coordinate expression of STAT3 targets was significantly associated with poor patient outcome in each data set. Specifically, patients with tumors displaying high expression of STAT3 targets had a shorter median survival time compared to patients whose tumors had low expression of STAT3 targets. These data suggest that constitutively activated STAT3 in gliomas can alter the biology of these tumors, and that development of targeted STAT3 inhibitors would likely be of particular benefit in treatment of this disease

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23 февраля 2011 года исполнилось 75 лет со дня рождения главного инженера Днепродзержинской ГЭС — Кучерявого Владислава Семеновича.15 июня 2011 г. исполняется 70 лет ученому — гидроэнергетику, доктору технических наук, начальнику отдела расчетного обоснования ПАО "Укргидропроект", профессору, заведующему кафедрой гидротехнического строительства Харьковского государственного технического университета строительства и архитектуры Александру Исааковичу Вайнбергу

New GFAP splice isoform (GFAPµ) differentially expressed in glioma translates into 21 kDa N-terminal GFAP protein

The glial fibrillary acidic protein (GFAP) is a type III intermediate filament (IF) protein that is highly expressed in astrocytes, neural stem cells, and in gliomas. Gliomas are a heterogeneous group of primary brain tumors that arise from glia cells or neural stem cells and rely on accurate diagnosis for prognosis and treatment strategies. GFAP is differentially expressed between glioma subtypes and, therefore, often used as a diagnostic marker. However, GFAP is highly regulated by the process of alternative splicing; many different isoforms have been identified. Differential expression of GFAP isoforms between glioma subtypes suggests that GFAP isoform-specific analyses could benefit diagnostics. In this study we report on the differential expression of a new GFAP isoform between glioma subtypes, GFAPµ. A short GFAP transcript resulting from GFAP exon 2 skipping was detected by RNA sequencing of human glioma. We show that GFAPµ mRNA is expressed in healthy brain tissue, glioma cell lines, and primary glioma cells and that it translates into a ~21 kDa GFAP protein. 21 kDa GFAP protein was detected in the IF protein fraction isolated from human spinal cord as well. We further show that induced GFAPµ expression disrupts the GFAP IF network. The characterization of this new GFAP isoform adds on to the numerous previously identified GFAP splice isoforms. It emphasizes the importance of studying the contribution of IF splice variants to specialized functions of the IF network and to glioma research