A Time-Decomposition Algorithm for the Solution of Multiple-Target Problems

An algorithm for solving the nonlinear optimal control problem whose system equation contains discontinuities is proposed. The boundary conditions are specified at several corner times as well as at the initial and the final times. Assuming that the corner times are known, by using the variational principle, the problem is reduced to a nonlinear multipoint boundary-value problem (MPBVP), which is further reduced to a linear one by use of an interaction-coordination algorithm. The linear MPBVP is solved by a discontinuous version of a time-decomposition algorithm, which decomposes the problem into a number of subinterval TPBVP's. The exact boundary conditions of these TPBVP's are determined by an algebraic method which utilizes the solution obtained with arbitrarily chosen boundary conditions. After solving the nonlinear MPBVP, the assumed corner times are corrected by a gradient method. Correction is iterated until the optimum is attained. The solution in each iteration satisfies the boundary conditions exactly. In order to verify the effectiveness of the present algorithm, a linear and a non-linear problem are solved numerically and the solution to the linear problem is compared with the analytical one

Inefficiency and Self-Determination: Simulation-Based Evidence from Meiji Japan

Does the exercise of the right of self-determination lead to inefficiency? This paper considers a set of centrally planned municipal mergers during the Meiji period, with data from Gifu prefecture. The observed merger pattern can be explained as a social optimum based on a very simple indiidual utility function. If individual villages had been allowed to choose their merger partners, counterfactual simulations show that the core is always non-empty, but core partitions contain about 80% more (post-merger) municipalities than the social optimum. Simulations are possible because core partitions can be calculated using repeated application of a mixed integer program

An Interaction-Coordination Algorithm with Time- and State-Decompositions for Nonlinear Optimal Control Problems

This paper proposes a computational algorithm for the multilevel control of a composite nonlinear dynamical system with the performance index of a quadratic type. First, for the solution of a linear two-point boundary-value problem (TPBVP), a computational technique, termed time-decomposition, is proposed. The time-decomposition implies decomposition of the system equations along the subintervals of the independent variable. The boundary conditions of each subinterval are determined algebraically in such a way that the continuity condition of the variables at the boundary points is satisfied. This technique plays an important role in the subsequent discussions. Second, a nonlinear optimal control problem is considered. The objective is to minimize the performance index of a quadratic type. For this problem, the authors have previously presented ‘the interaction-coordination algorithm with modified performance index.’ The basic idea of this algorithm is to decompose the overall nonlinear problem into a number of smaller linear subproblems. Here this kind of decomposition is termed state-decomposition. In the present paper, a computational algorithm by use of both the time- and the state-decomposition is proposed. The algorithm essentially constructs a three-level computational structure, and results in a fast convergence even for problems with strong nonlinearities and/or a long control interval

Experience of Cadaver Donor Nephrectomy with Cadaver Surgical Training

As cadaver donor nephrectomy in kidney transplantation is performed in only a limited number of cases, few physicians are skilled in the surgical technique. We performed two cadaver donor nephrectomy sessions during cadaver surgical training. The first session was performed by a lecturer who was skilled in the technique, with physicians and nurses participating in order to learn the methodology. The second session was conducted only for physicians. The procedures undertaken were as follows: cannulation of the femoral artery and vein, skin incision and bowel ligation, cross-clamping of the aorta, diaphragmatic incision and inferior vena cava incision, dissection of the aorta and inferior vena cava, and nephrectomy. Although there were some differences from that normally observed in actual patient surgery, such as no bleeding and formalin fixation, some of the procedures were very useful in helping to better understand cadaver donor nephrectomy

TGF-β type II receptor expression in thymic epithelial cells inhibits the development of Hassall's corpuscles in mice

TGF-βRII signaling prevents the development of Hassall's corpuscle

Utility of the HYBRID Method Incorporating the Advantages of Both Extracorporeal and Intracorporeal Urinary Diversion in Robotic-Assisted Radical Cystectomy

Background: Robotic-assisted radical cystectomy (RARC) is a well-known standard procedure for muscle-invasive bladder cancer. However, it remains controversial whether extracorporeal urinary diversion (ECUD) or intracorporeal urinary diversion (ICUD) is superior in this technique. We have developed a HYBRID method that combines ECUD and ICUD to retain the advantages of each. The purpose of this study was to compare perioperative outcomes between HYBRID and ECUD in RARC and to evaluate the usefulness of the HYBRID method. Methods: We retrospectively analyzed the perioperative outcomes of 36 consecutive bladder cancer patients who underwent RARC with ileal conduit at our institution between March 2013 and December 2021. Propensity-score matching was used to align patient backgrounds between the HYBRID and ECUD groups. Results: After matching, 12 cases were selected for each group. There was no significant difference in patient demographics between the groups except for the rate of neoadjuvant chemotherapy. Mean console time was significantly longer in the HYBRID group due to intracorporeal manipulation; however, a relatively favorable trend of mean blood loss was observed in this group. There was no significant difference between the groups in terms of positive surgical margin, mean number of lymph node removed, or positive lymph node. The incidences of complications associated and non-associated with the urinary tract and grade ≥III complications at postoperative day (POD) 0–30 and 31–90 were similar between the groups. In the HYBRID group, no complications non-associated with the urinary tract or grade ≥III complications were observed at POD 31–90. Conclusion: The HYBRID method takes advantage of the benefits of both ICUD and ECUD and is a highly applicable technique that can be used in a variety of patient backgrounds

Optimal Number of Systematic Biopsy Cores Used in Magnetic Resonance Imaging/Transrectal Ultrasound Fusion Targeted Prostate Biopsy

[Background] In recent years, the effectiveness of magnetic resonance imaging (MRI)-ultrasound fusion targeted biopsy (MRF-TB) has been widely reported. In this study, we assessed the effect of reduction of the number of systematic biopsy (SB) cores on the cancer detection rate (CDR). [Methods] Patients with a high prostate-specific antigen (PSA) level underwent prostate MRI. The Prostate Imaging-Reporting and Data System version 2 (PI-RADS) was then used to rate the lesions. The inclusion criteria were as follows: (1) PSA level between 4.0 and 30.0 ng/mL and (2) patients with one or more lesions on MRI and a PI-RADS score of 3 or more. All enrolled patients were SB naïve or had a history of one or more prior negative SBs. A total of 104 Japanese met this selection criterion. We have traditionally performed 14-core SB following the MRF-TB. In this study, the CDRs of 10-core SB methods, excluding biopsy results at the center of the base and mid-level on both sides, were compared with those of the conventional biopsy method. [Results] We compared CDRs of the 14-core and 10-core SBs used in combination. The overall CDR was 55.8% for the former and 55.8% for the latter, thereby indicating that there was no significant difference (P = 1.00) between the two. In addition, the CDRs of csPCa were 51.9% for the former and 51.1% for the latter, which indicated that there was no significant difference (P = 0.317). [Conclusion] There was no significant difference in the CDR when the number of SB cores to be used in combination was 14 and 10

CD59 protects rat kidney from complement mediated injury in collaboration with Crry

CD59 protects rat kidney from complement mediated injury in collaboration with Crry.BackgroundAs previously reported, the membrane-bound complement regulator at the C3 level (Crry/p65) is important in maintaining normal integrity of the kidney in rats. However, the role of a complement regulator at the C8/9 level (CD59) is not clear, especially when activation of complement occurs at the C3 level. The aim of this work was to elucidate the in vivo role of CD59 under C3 activating conditions.MethodsTwo monoclonal antibodies, 5I2 and 6D1, were used to suppress the function of Crry and CD59, respectively. In order to activate alternative the pathway of complement, the left kidney was perfused with 5I2 and/or 6D1 and was recirculated.ResultsIn the kidneys perfused with 5I2 alone, deposition of C3 and membrane attack complex (MAC) was observed in the peritubular capillaries, vasa recta, and tubular basement membranes. Cast formation, tubular dilation and degeneration, and cellular infiltration were observed at days 1 and 4, and they recovered by day 7. Further suppression of CD59 by 6D1 significantly enhanced the deposition of MAC and worsened the already exacerbated tubulointerstitial injury. These effects of 6D1 were dose dependent. Perfusion with 6D1 alone did not induce histologic damage or MAC deposition in the tubulointerstitium.ConclusionsIn rats, CD59 maintains normal integrity of the kidney in collaboration with Crry in rats against complement-mediated damage in vivo

Cancer activity and bleeding events post-PCI

Purpose : Limited data exist about clinically relevant bleeding events related to antiplatelet therapy after percutaneous coronary intervention (PCI) in cancer patients. We investigated the risk factors for clinically relevant bleeding events in patients with cancer after PCI with stent implantation. Patients and Methods : Patients with solid cancer subjected to first PCI were divided into active (n = 45) and non-active cancer groups (n = 44). The active group included non-operable patients on treatment or with metastasis ; the non-active included those already subjected to or for whom radical surgery was planned within 3 months after the index PCI. Results : During a median follow-up of 2.2 years, 11 bleeding events occurred, with only one occurring in the non-active cancer group. Half of them occurred during the dual-antiplatelet therapy (DAPT) period, and the rest occurred during single-antiplatelet therapy (SAPT) period. Kaplan-Meier analysis showed significantly more bleeding events in the active cancer group (p = 0.010). Multivariate Cox regression hazard analysis revealed cancer activity as a significant independent risk factor for bleeding (p = 0.023) ; but not for three-point major adverse cardiovascular events. Conclusion : Clinically relevant bleeding risk after PCI was significantly lower in non-active cancer. Active cancer group had clinically relevant bleeding during both DAPT and SAPT periods