The role of the orbitofrontal cortex in human adaptive learning under strategic environments

This paper proposes an augmented learning model from a neuroscience perspective. This model contains brain activity data of the orbitofrontal cortex as a predictive variable of human strategic behavior. A Bayesian 3-layer perceptron, which shows the complex relationship between decision factors, was adopted to describe the learning behavior. However, the model's complexity creates the possibility of overtting. To avoid this problem, we adopt the Bayesian estimation and Akaike's Bayesian information criteria, which provide the statistical basis of the model selection, to select the model. Our experience shows that this model can better predict human strategic behavior than do existing behavioral learning models.neuroeconomics, learning model, orbitofrontal cortex, neural network,

Near-Infrared search for C IV absorption counterparts along the line-of-sights to pair quasars

We carried out a Subaru and UKIRT near infrared imaging survey for H-alpha emitting galaxies around two pair quasar systems (Q0301-005/Q0302-003 and Q2343+125/Q2344+125), and a triple quasar system (KP76/KP77/KP78). Narrow band near infrared filters covering the H-alpha emission expected for galaxies at the confirmed C IV absorption redshift toward the quasar systems were used for this survey. These quasar pairs or triplet are separated at most by 17 arcmins (~5 h^-1 Mpc in proper distance) from each other on the sky, and have common C IV absorption lines at almost identical redshifts at z=2.24-2.43, which suggests there could be a Mpc-scale absorbing systems such as a cluster, or a group, of galaxies that cover all the line-of-sights to the pair/triple quasars. Using narrow-band deep images, we detected five candidates for H-alpha emitting galaxies around two of the six fields, Q2343+125 and Q2344+125, whose apparent star formation rates are, extremely high, 20-466 M_solar/year. However, all or most of them are not likely to be galaxies at the absorption redshift but galaxies at lower redshift, because of their extreme brightness. In the fields of the other quasars, we detected no star-forming galaxies, nor did we find any number excess of galaxy counts around them. This no-detection results could be because the luminosities and star formation rates of galaxies are lower than the detection limits of our observations (K' > 21 and SFR < 1.8-240 h^-2 M_solar/year). They could be located outside of the observed fields by chance. Otherwise, most C IV absorption lines could be ascribed not to cluster of galaxies, but to isolated star forming pockets far from bright galaxies and could be analogous objects to weak Mg II absorbers.Comment: 9 pages, including 5 figures; accepted for publication in the Astronomical Journa

How many times can patients tolerate reoperation?

The frequency of resection for the recurrence of colorectal cancer has not been investigated in previous studies. Likewise, the related postoperative complications and the limit for indicating surgical resection has not been reported. Herein, we reported the complications of a highly frequent surgical approach for rectal cancer recurrence, i.e., exceeding three reoperations, based on our clinical experience. We included 15 cases exceeding two operations for the local recurrence of colorectal cancer from 2014 to 2019. We examined the postoperative complications classified as Clavien–Dindo IIIb. The positive rates of the complications were 0 (0.0%), 0 (0.0%), 2 (13.3%), 3 (37.5%), and 0 (0.0%) for the primary, 1st recurrent, 2nd recurrent, 3rd recurrent, and 4th recurrent operation group (p = 0.027), respectively. It is important to exercise caution in handling cases exceeding two reoperations (exceeding three reoperations including the primary operation)

Solitary distant peritoneal metastasis of cecal cancer after laparoscopic colectomy : a case report

A 77-year-old Japanese female underwent laparoscopic ileocecal resection and lymph node dissection for cecal cancer by a previous doctor. Two years and 9 months after previous operation, contrast-enhanced computed tomography and magnetic resonance imaging with gadolinium ethoxybenzyl-L-diethylenetriamine pentaacetic acid revealed an intraperitoneal tumor at the right subphrenic fossa. 18F-fluorodeoxyglucose position emission tomography showed fluorodeoxyglucose accumulation in the tumor, and we suspected the tumor to be solitary distant peritoneal metastasis of the previous cecal cancer to the right diaphragm. We performed partial diaphragmectomy and direct closure, and pathological examination revealed moderately differentiated tubular adenocarcinoma resembling the previous cecal cancer, which seemed to be disseminated metastasis in the pathological features. Based on the intraoperative findings, we assumed the tumor to be solitary distant peritoneal metastasis caused by procedures during the previous laparoscopic operation. The present report suggests the importance of paying close attention to procedures during laparoscopic colorectal resection to prevent peritoneal seeding

Coincident Port-site and Functional End-to-end Anastomotic Recurrences after Laparoscopic Surgery for Colon Cancer : A case report and literature review

Herein, we report coincident recurrences at the port site and functional end-to-end anastomosis after laparoscopic right hemicolectomy for cancer of the ascending colon. The patient was an 83-year-old man who had undergone the aforementioned procedure (Stage IIA) in the referral hospital. At the 10-month follow-up, computed tomography showed two tumours around 3 cm in diameter : one on the right-flank abdominal wall-the surgical port-site-and the other at the functional end-to-end anastomosis. Likewise, a positron emission tomography scan was positive for two tumours. Endoscopic examination showed an ulcerated tumour with a clear margin, and a biopsy confirmed moderately differentiated tubular adenocarcinoma. The patient was diagnosed with coincident recurrences at the port site and functional end-to-end anastomosis after laparoscopic right hemicolectomy for cancer of the ascending colon. We re-operated inMarch 2016. The tumours at the functional end-to-end anastomosisand functional end-to-end anastomosiswere resected. After 7 months, no recurrence was detected

Peritoneal cecal cancer metastasis to a mesh-plug prosthesis : A case report

We report the case of a 77-year-old man who presented to our hospital with cecal cancer, lung metastasis, and liver metastasis in January 2013. After four courses of modified infusional intravenous fluorouracil and levofolinate with oxaliplatin (mFOLFOX 6) + bevacizumab, there was no new metastatic lesion and lung metastasis reduction was observed. Ileocecal resection was performed in May, left lower lung lobectomy in August, and extended right posterior segmentectomy + S8 partial liver resection was performed in December. The tumor marker declined initially ; thereafter, it gradually increased. Computed tomography (CT) performed in April 2014 revealed right inguinal mass around the mesh-plug prosthesis. A positron emission tomography-CT (PET-CT) also revealed a high 2-fluoro-2-deoxy-D-glucose (FDG) uptake at the same site. Right inguinal tumor resection was performed in July. Cancer tissues were confirmed by performing intraoperative rapid pathological diagnosis, and R0 resection could be achieved. Previous studies have reported malignant tumor metastases to the mesh-plug prosthesis, and this was believed to one of the sites that cancer cells can easily engraft. In particular, in patients with a history of advanced malignant tumors, if mass formation around the artifact insertion site is observed, the possibility of peritoneal metastasis should be considered

Combined resection of re-recurrent lateral lymph nodes and external iliac vein : Case Report and Literature

Herein, we describe the operative procedure for combined resection of re-recurrent lateral lymph nodes and the external iliac vein. There is no consensus on the clinical implications of resection of locally re-recurrent colorectal tumors, as the operative procedure is extremely difficult. We present the case of a 52- year-old woman who underwent abdominoperineal resection. About one year later, we excised a recurrent lymph node in the left lateral obturator area through an extraperitoneal approach. About 18 months later, lymph node re-recurrence in the left external iliac area was observed. Re-recurrent lymph nodes directly invade the left external iliac vein.We removed the re-recurrent lymph node with combined, radical segmental resection of the left external iliac vein, left obturator artery and vein, and left obturator nerve