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We investigate spatially inhomogeneous solutions in a top-down holographic model: the D3/D7 model which provides a holographic description of the chiral phase transition for a finite external magnetic field, chemical potential, and temperature. We numerically find a domain wall (or kink) solution in the three dimensional space, which incorporates between the chiral symmetry broken phase at the spatial infinity, under the homogeneous sources. Along with the inhomogeneity of the chiral condensate, the charge density is also spatially modulated. The modulated charge density and finite magnetic field lead to the chiral edge current close to the domain wall. We explore the dependences of those profiles on the chemical potential and temperature near the first and second order phase transition points. Our results indicate that the inhomogeneous solutions we found are in good agreement with those obtained by the Ginzburg-Landau theory in the vicinity of the transition points. [ABSTRACT FROM AUTHOR]

We study critical phenomena at a tricritical point associated with a chiral phase transition which emerges in the D3/D7 model in the presence of a finite baryon number density and an external magnetic field. We numerically determine critical exponents related to the thermodynamic quantities and correlation functions. We find that the values of the critical exponents agree with the mean-field values. The scaling relations between the critical exponents are satisfied, implying that the scaling hypothesis for the free energy and the correlation functions hold. Our results indicate that the critical phenomena at the tricritical point in the D3/D7 model are well described by the conventional Landau theory. [ABSTRACT FROM AUTHOR]

We study the meson spectrum of the N = 4 supersymmetric Yang-Mills theory with N = 2 fundamental hypermultiplets for a finite electric field by using the D3/D7 model. The spectrum for scalar and vector mesons is computed by analyzing the (quasi-)normal modes for the fluctuations of the D7-brane embedding and gauge fields. In the presence of an electric field, two different phases in the background are realized: the meson and dissociation phases. In this paper, we analyze the meson spectrum of scalar and vector mesons for all ranges of the electric field and explore the effect of the electric field on the meson spectrum, that is, the Stark effect. In the meson spectrum, we observe the avoided crossing between different levels due to the coupling of fluctuations via the electric field. [ABSTRACT FROM AUTHOR]

We study phase transitions and critical phenomena in nonequilibrium steady states controlled by an electric field. We employ the D3/D7 model in the presence of a charge density and electric field at finite temperatures. The system undergoes the first-order and the second-order phase transitions under the variation of the electric field in the presence of dissipation. We numerically find that the critical exponents which we define for the nonequilibrium phase transition in this model take the mean-field values. [ABSTRACT FROM AUTHOR]

We study phase transitions and critical phenomena in nonequilibrium steady states controlled by an electric field. We employ the D3/D7 model in the presence of a charge density and electric field at finite temperatures. The system undergoes the first-order and the second-order phase transitions under the variation of the electric field in the presence of dissipation. We numerically find that the critical exponents which we define for the nonequilibrium phase transition in this model take the mean-field values. [ABSTRACT FROM AUTHOR]

Purpose: Although reports suggest that the pancreatic volume decreases after gastrectomy for gastric cancer, the relationship between the pancreatic volume and secretory function after gastrectomy remains unclear. In this study, we examined the relationship between the pancreatic volume and exocrine and endocrine functions after total gastrectomy. Methods: The pancreatic volumes of 18 distal gastrectomy and 15 total gastrectomy patients were retrospectively measured using computed tomography volumetry up to 5 years postoperatively. Ten low anterior resection patients were selected as controls. In addition, the pancreatic volume and exocrine function evaluated by fecal elastase and the insulin secretory function evaluated by glucagon tolerance testing were prospectively examined before and one year after surgery in nine cases of total gastrectomy. Results: After low anterior resection, the pancreatic volume did not change, but after distal and total gastrectomy, the pancreatic volume decreased continuously until the fifth year. After total gastrectomy, fecal elastase decreased significantly from 865.8 μg/g to 603.2 μg/g in the first year (p = 0.0316), and the insulin secretion capacity also decreased significantly from 3.83 ng/mL to 2.26 ng/mL (p = 0.0019). Conclusions: The pancreatic volume decreases continuously after gastrectomy for gastric cancer, and the pancreatic exocrine and endocrine functions decrease along with pancreatic atrophy after total gastrectomy. [ABSTRACT FROM AUTHOR]

Backgrounds: Liver resection for hepatocellular carcinoma (HCC) in patients with Child–Pugh class (CPC) B increases the incidence of postoperative complication and in-hospital death and decreases the disease-free survival (DFS) and overall survival (OS) compared with those with CPC A. Conversely, some selected patients possibly gained benefits for liver resection. Methods: Clinical records of 114 patients with CPC B who underwent liver resection for HCC were retrospectively reviewed. The risk of postoperative complications (Clavien–Dindo classification grade of ≥ II), postoperative recurrence, and death was analyzed. Results: Postoperative complications occurred in 36 patients (31.6%), and 2 died within 90 days postoperatively due to the liver and respiratory failure, respectively. Multivariate analysis indicated that albumin-bilirubin (ALB) grade III and extended operation time were found as independent risk factors for postoperative complications. The DFS and OS rates at 3/5 years after liver resection were 30.8%/25.3% and 68.4%/48.9%, respectively. Multivariate analysis indicated that the extended blood loss, high α-fetoprotein (AFP) level (≥ 200 ng/mL), and Barcelona Clinic Liver Cancer stage C were found to be independent risk factors for postoperative recurrence. The high AFP level was also an independent prognostic factor for OS. Patients with high AFP levels had postoperative recurrence within 2 years and a higher number of extrahepatic recurrences than those with low AFP levels (< 200 ng/mL). Conclusion: For patients with HCC with CPC B who were scheduled for liver resection, ALBI grade III and high AFP level should be considered as unfavorable outcomes after liver resection. [ABSTRACT FROM AUTHOR]

Background: This study aimed to determine the risk factors for severe postoperative complications in patients undergoing pure laparoscopic liver resection (LLR) for tumors in the right posterosuperior (PS) segments. Methods: The study included 289 patients who underwent parenchyma‐sparing pure LLR for tumors in the right PS segments at eight treatment centers between January 2009 and December 2019. Results: Multivariate analysis revealed tumor size ≥3 cm (P =.016), segmentectomy (P =.044), and liver cirrhosis (P =.029) as independent risk factors for severe postoperative complications. The severe complication rates (2.7% vs 12.1%, P =.0025), median intraoperative blood loss (100 mL vs 150 mL, P =.001), and median operation time (248 minutes vs 299.5 minutes, P =.0013) were lower in the patients without all these three risk factors than those with at least one risk factor. The median length of postoperative hospital stay was shorter in patients with no risk factors than those with at least one risk factor (9 days vs. 10 days, P =.001). Conclusions: Tumor size ≥3 cm, segmentectomy, and liver cirrhosis were the risk factors for severe postoperative complications after parenchyma‐sparing pure LLR for tumors in the right PS segments. Patients without these three risk factors would be appropriate candidates for safely performing parenchyma‐sparing pure LLR in the right PS segments at the outset. [ABSTRACT FROM AUTHOR]

Purpose: Postoperative pancreatic fistula (POPF) remains the most clinically relevant complication of laparoscopic distal pancreatectomy (LDP). The present study evaluated the efficacy of the "slow firing method" using a reinforced triple-row stapler (Covidien, Tokyo, Japan) during LDP. Methods: This retrospective single-center study included 73 consecutive patients who underwent LDP using the slow firing method. A black cartridge was used in all patients. The primary endpoint was the rate of clinically relevant POPF (CR-POPF) after LDP. Secondary endpoints included perioperative outcomes and factors associated with CR-POPF as well as the correlation between the transection time and thickness of the pancreas. Results: Four patients (5.5%) developed CR-POPF (grade B). Overall morbidity rates, defined as grade ≥ II and ≥ III according to the Clavien-Dindo classification, were 21 and 11%, respectively. The median postoperative hospital stay was 10 days. Preoperative diabetes (13.6 vs. 0.2%, P = 0.044) and thickness of the pancreas ≥ 15 mm (13.8% vs. 0%, P = 0.006) were identified as independent risk factors for CR-POPF. The median transection time was 16 (8–29) min. Conclusion: The slow firing method using a reinforced triple-row stapler for pancreatic transection is simple, safe, and effective for preventing CR-POPF after LDP. [ABSTRACT FROM AUTHOR]