A Bayesian approach to constrained single- and multi-objective optimization

This article addresses the problem of derivative-free (single- or multi-objective) optimization subject to multiple inequality constraints. Both the objective and constraint functions are assumed to be smooth, non-linear and expensive to evaluate. As a consequence, the number of evaluations that can be used to carry out the optimization is very limited, as in complex industrial design optimization problems. The method we propose to overcome this difficulty has its roots in both the Bayesian and the multi-objective optimization literatures. More specifically, an extended domination rule is used to handle objectives and constraints in a unified way, and a corresponding expected hyper-volume improvement sampling criterion is proposed. This new criterion is naturally adapted to the search of a feasible point when none is available, and reduces to existing Bayesian sampling criteria---the classical Expected Improvement (EI) criterion and some of its constrained/multi-objective extensions---as soon as at least one feasible point is available. The calculation and optimization of the criterion are performed using Sequential Monte Carlo techniques. In particular, an algorithm similar to the subset simulation method, which is well known in the field of structural reliability, is used to estimate the criterion. The method, which we call BMOO (for Bayesian Multi-Objective Optimization), is compared to state-of-the-art algorithms for single- and multi-objective constrained optimization

Reframing Kurtz’s Painting: Colonial Legacies and Minority Rights in Ethnically Divided Societies

Minority rights constitute some of the most normatively and economically important human rights. Although the political science and legal literatures have proffered a number of constitutional and institutional design solutions to address the protection of minority rights, these solutions are characterized by a noticeable neglect of, and lack of sensitivity to, historical processes. This Article addresses that gap in the literature by developing a causal argument that explains diverging practices of minority rights protections as functions of colonial governments’ variegated institutional practices with respect to particular ethnic groups. Specifically, this Article argues that in instances where colonial governments politicize and institutionalize ethnic hegemony in the pre-independence period, an institutional legacy is created that leads to lower levels of minority rights protections. Conversely, a uniform treatment and depoliticization of ethnicity prior to independence ultimately minimizes ethnic cleavages post-independence and consequently causes higher levels of minority rights protections. Through a highly structured comparative historical analysis of Botswana and Ghana, this Article builds on a new and exciting research agenda that focuses on the role of long-term historio-structural and institutional influences on human rights performance and makes important empirical contributions by eschewing traditional methodologies that focus on single case studies that are largely descriptive in their analyses. Ultimately, this Article highlights both the strength of a historical approach to understanding current variations in minority rights protections and the varied institutional responses within a specific colonial government

Lacrimal Gland Involvement in Lymphomatoid Granulomatosis and Review of the Literature

Objective. To describe the clinicoradiological and histopathological findings in a case of lacrimal gland enlargement secondary to lymphomatoid granulomatosis (LG) and to review the literature. Design. Case report and systematic literature review. Methods. A 75-year-old woman presented with right ptosis. Computerised tomography showed lacrimal gland enlargement, and biopsy done was inconclusive. She subsequently developed pulmonary symptoms and underwent transbronchial biopsy that was diagnosed as LG. Pub Med and OVID databases were searched using the term “orbit/eye involvement in lymphomatoid granulomatosis”. Articles that predated the databases were gathered from current references. Results. The patient underwent lacrimal gland biopsy which revealed necrotic and inflamed tissue with no further categorisation but transbronchial biopsy helped in establishing the diagnosis of LG. On initiation of prednisolone and cyclophosphamide, her orbital lesion resolved but the patient died following massive pulmonary hemorrhage within a month of diagnosis. Conclusion. Ophthalmic involvement in LG is very rare. Varied presentations are due to central nervous system involvement, vasculitis, or infiltration of ocular or orbital structures. LG is an angiocentric and angiodestructive granulomatous disorder and can involve any tissue, thus accounting for the variable presentations reported in literature

Laparoscopic Retrieval of a Peritoneal Mouse

A 67-year-old Caucasian male was referred by the urology service with a history of incomplete bowel emptying. He complained of tenesmus. MRI scan suggested a leiomyoma lying anterior to the rectum. He underwent examination under anaesthesia and attempted endorectal ultrasound and biopsy. However, the lesion seemed to migrate cranially and was impalpable. At laparoscopy, a mobile, unattached, 5.5 × 5 × 3.5, cream-coloured ‘egg was retrieved from the retrovesical space. Histology confirmed a hyalinised fibrocollagenous lesion lined with mesothelium. A comprehensive review of the literature is presented

Large Intra-Articular Anterior Cruciate Ligament Ganglion Cyst, Presenting with Inability to Flex the Knee

A 41-year-old female presented with a 3-month history of gradually worsening anterior knee pain, swelling and inability to flex the knee. Magnetic resonance imaging (MRI) revealed a large intra-articular cystic swelling anterior to the anterior cruciate ligament (ACL), extending into the Hoffa's infrapatellar fat pad. Following manipulation under anaesthesia and arthroscopic debridement of the cyst, the patient's symptoms were relieved with restoration of normal knee motion. ACL ganglion cysts are uncommon intra-articular pathological entities, which are usually asymptomatic and diagnosed incidentally by MRI. This is the first reported case of an ACL cyst being so large as to cause a mechanical block to knee flexion

A Unique Case of Autoimmune Retinopathy Associated with Anti-Alpha-Enolase Antibodies

Background. We report a case of autoimmune retinopathy associated with anti-alpha-enolase antibodies with unique manifestations. Methods. A case report. Results. A 30-year-old male experienced recurrent, primarily peripheral visual field disturbances and minimal photopsia, with interval symptom resolution. Fundus changes subsequently developed in areas corresponding to the previous visual field symptoms. Electroretinogram showed bilaterally symmetric abnormalities of light-adapted responses and suggested loss of photoreceptor function. Only anti-alpha-enolase antibodies were detected on Western blot. Our patient noted cutaneous symptoms at the time of both episodes of visual symptoms, but not in the interim. Biomicroscopy revealed subtle small reddish spots in areas of the peripheral retina corresponding to the areas of the patient's visual field where he noted symptoms. To our knowledge these reddish spots have not been reported in autoimmune retinopathy and may clinically support in vitro and in vivo evidence that anti-alpha-enolase antibodies may target photoreceptors. Conclusions. Our patient demonstrates some unique features adding to the known characteristics of autoimmune retinopathy associated with anti-alpha-enolase antibodies. As more cases are reported, further understanding of the features and pathophysiology of this rare condition will hopefully be elucidated