Robust Deviations from Signaling Equilibria

In Sender-Receiver games with costly signaling, some equilibria are vulnerable to deviations which could be "unambiguously" interpreted by the Receiver as coming from a unique set of possible Sender-types. The vulnerability occurs when the types in this set are the ones who gain from the deviation, regardless of the posterior beliefs the Receiver forms over that set. We formalize this idea and use it to characterize a unique equilibrium outcome in two classes of games. First, in mono- tonic signaling games, only the Riley outcome is immune to this sort of deviation. Our result therefore provides a plausible story behind the selection made by Cho and Kreps' (1987) D1 criterion on this class of games. Second, we examine a version of Crawford and Sobel's (1982) model but with costly signaling and finite type sets, where standard refinements have no effect. We show that only a Riley-like separating equilibrium is immune to these deviations.Signaling games, Sender-Receiver, robust equilibrium, re¯nements.

The Price of Advice

We develop a model of consulting (advising) where the role of the consultant is that she can reveal signals to her client which refine the client’s original private estimate of the profitability of a project. Importantly, only the client can observe or evaluate these signals, the consultant cannot. We characterize the optimal contract between the consultant and her client. It is a menu consisting of pairs of transfers specifying payments between the two parties (from the client to the consultant or vice versa) in case the project is undertaken by the client and in case it is not. The main result of the paper is that in the optimal mechanism, the consultant obtains the same profit as if she could evaluate the impact of the signals (whose release she controls) on the client’s profit estimate.Mechanism Design, Information Disclosure, Consulting, Advising

Identifikasi Antropogenik Pencemaran Tanah oleh Sampah Domestik

Abstrak :Telah dilakukan penelitian tentang antropogenik pencemaran tanah dengan menganalisis kandungan logam berat tanah pada tumpukan sampah  di sekitar pemukiman tepatnya di jalan Chairil Anwar, Kecamatan Wua-Wua, Kota Kendari. Sampel tanah di gali menggunakan bor tanah dengan kedalaman 0 sampai 90 cm  yang seterusnya dihaluskan dan diayak dengan ayakan 200 mess. Sampel tanah dianalisis dengan metode XRF (X-Ray Fluorescence) untuk mengidentifikasi kandungan logam berat di dalam tanah. Sementara itu, suseptibilitas magnetik tanah dianalisis dengan menggunakan susceptibilitiy meter Bartington MS2B untuk mengetahui sifat magnetiknya.   Hasil pengukuran menunjukkan bahwa tanah tersebut telah tercemar  unsur logam berat seperti  Besi, Mangan, Seng,  dan Chromium dengan persentase  yang jauh melebihi ambang batas yang seharusnya ada dalam tanah, sementara itu  kandungan unsur logam berat Pb (Timbal),  As (Arsenik) dan Cu (Tembaga) belum melampaui ambang batasnya. Berdasarkan hasil analisis sifat magnetik tanah sumber pencemaran tanah berasal dari antropogenik aktivitas manusia.Keywords: Antropogenik, pencemaran tanah, suseptibilitas magneti

Doctor of Philosophy

dissertationCongenital heart defects are classes of birth defects that affect the structure and function of the heart. These defects are attributed to the abnormal or incomplete development of a fetal heart during the first few weeks following conception. The overall detection rate of congenital heart defects during routine prenatal examination is low. This is attributed to the insufficient number of trained personnel in many local health centers where many cases of congenital heart defects go undetected. This dissertation presents a system to identify congenital heart defects to improve pregnancy outcomes and increase their detection rates. The system was developed and its performance assessed in identifying the presence of ventricular defects (congenital heart defects that affect the size of the ventricles) using four-dimensional fetal chocardiographic images. The designed system consists of three components: 1) a fetal heart location estimation component, 2) a fetal heart chamber segmentation component, and 3) a detection component that detects congenital heart defects from the segmented chambers. The location estimation component is used to isolate a fetal heart in any four-dimensional fetal echocardiographic image. It uses a hybrid region of interest extraction method that is robust to speckle noise degradation inherent in all ultrasound images. The location estimation method's performance was analyzed on 130 four-dimensional fetal echocardiographic images by comparison with manually identified fetal heart region of interest. The location estimation method showed good agreement with the manually identified standard using four quantitative indexes: Jaccard index, Sørenson-Dice index, Sensitivity index and Specificity index. The average values of these indexes were measured at 80.70%, 89.19%, 91.04%, and 99.17%, respectively. The fetal heart chamber segmentation component uses velocity vector field estimates computed on frames contained in a four-dimensional image to identify the fetal heart chambers. The velocity vector fields are computed using a histogram-based optical flow technique which is formulated on local image characteristics to reduces the effect of speckle noise and nonuniform echogenicity on the velocity vector field estimates. Features based on the velocity vector field estimates, voxel brightness/intensity values, and voxel Cartesian coordinate positions were extracted and used with kernel k-means algorithm to identify the individual chambers. The segmentation method's performance was evaluated on 130 images from 31 patients by comparing the segmentation results with manually identified fetal heart chambers. Evaluation was based on the Sørenson-Dice index, the absolute volume difference and the Hausdorff distance, with each resulting in per patient average values of 69.92%, 22.08%, and 2.82 mm, respectively. The detection component uses the volumes of the identified fetal heart chambers to flag the possible occurrence of hypoplastic left heart syndrome, a type of congenital heart defect. An empirical volume threshold defined on the relative ratio of adjacent fetal heart chamber volumes obtained manually is used in the detection process. The performance of the detection procedure was assessed by comparison with a set of images with confirmed diagnosis of hypoplastic left heart syndrome and a control group of normal fetal hearts. Of the 130 images considered 18 of 20 (90%) fetal hearts were correctly detected as having hypoplastic left heart syndrome and 84 of 110 (76.36%) fetal hearts were correctly detected as normal in the control group. The results show that the detection system performs better than the overall detection rate for congenital heart defect which is reported to be between 30% and 60%

Current status of treatment with immune checkpoint inhibitors for gastrointestinal, hepatobiliary, and pancreatic cancers

The development of immune checkpoint inhibitors (ICIs) targeting cytotoxic T lymphocyte antigen 4 (CTLA-4), programmed cell death protein 1 (PD-1), or programmed cell death protein ligand 1 (PD-L1) has revolutionized the treatment strategy in various types of cancers. In addition, recent studies have revealed that tumor microsatellite instability (MSI) status and tumor mutation burden (TMB) contribute significantly to the therapeutic response to anti-PD-1 monoclonal antibody (mAb), which led to an accelerated approval to pembrolizumab for the treatment of MSI-high or mismatch-repair-deficient solid tumors after conventional chemotherapies in 2017 and for the treatment of TMB-high solid tumors in 2020 by the United States Food and Drug Administration (FDA). In the field of gastrointestinal cancers, many clinical trials evaluating the safety and efficacy of various regimens such as ICI monotherapy, the combination of anti-CTLA-4 mAb and anti-PD-1/PD-L1 mAb, and combination of ICI and conventional chemotherapy or tyrosine kinase inhibitor have been reported or are in progress. This review summarizes MSI status and TMB in gastrointestinal, hepatobiliary, and pancreatic cancers, and provides the results of most relevant clinical trials evaluating ICIs. We also discuss the development of biomarkers required for improving the selection of patients with a high probability of benefiting from treatment with ICIs, and potential therapeutic strategies that could help to enhance anticancer responses of ICIs