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Near-limit characteristics of chain-branching premixed flames is investigated numerically and asymptotically by employing the Zel'dovich–Liñán two-step mechanism with linear and (sufficiently) fast recombination, for which both chain-branching and -recombination steps take place in a thin reactive layer of O (β − 1) , with β being the chain-branching Zel'dovich number. The numerical and asymptotic results reveal that the rate-ratio eigenvalue r between the chain branching and recombination steps approaches a minimum critical value of r m i n → e as the chain-recombination step becomes infinitely fast. The existence of the finite asymptotic value of r = e indicates that no steadily propagating flame solution can be found for fuel concentrations lower than its critical value, corresponding to the criticality of r = e , thereby explaining the (lean) flammability limit. This intrinsic flammability characteristics with linear recombination is the most outstanding contrast to the quadratic recombination counterpart, for which flammability is achieved only with external heat loss added to the model. Novelty and significance statement Near-limit combustion characteristics of chain-branching flames is investigated numerically and asymptotically by employing the Zel'dovich–Linan two-step chemical kinetics with linear and fast recombination. This work demonstrates that the rate-ratio eigenvalue between the chain-branching and -recombination steps asymptotically approaches a critical minimum value, corresponding to the flammability limit. The existence of flammability limit with the linear recombination is found to be the most significant contrast to the quadratic recombination model, which is incapable of predicting flammability limit. By this study, a formal asymptotic procedure, by which the crossover temperature and lean flammability limit condition can be determined without assuming a steady-state approximation of intermediate species, is established and can be applied to analyze flame structures with multi-step reduced mechanisms. [ABSTRACT FROM AUTHOR]

A semiconductor manufacturing process problem is presented. The problem is specifically one that involves work-in-process projection of processing lines having multiple levels. The solution involves finding a way to converting the work-in-process inventory into a systematic schedule of finished product to estimate net demand and net resource capacities. A heuristic formulation and an LP approach are subsequently recommended.

Abstract Concerns about environmentally sustainable supply chain management have increased widely in recent years. As a consequence, supply chain members have cooperated with one another to make efficient contracts, frequently called green supply-chain management contracts. The purpose of this paper is to investigate one such contract between a single manufacturer and multiple retailers with limited resources for several types of products under greenhouse-gas emission regulations. Each retailer orders the products regularly within a limited budget and warehouse capacity. In response to orders, the manufacturer produces products and ships them after inspections. Demand for the products can be either known or have some uncertainty, which can best be represented using fuzzy number demand. To reflect demand properties, this paper introduces two nonlinear integer programming models, a crisp model and a fuzzy model. A genetic algorithm (GA) and hybrid genetic algorithm-pattern search (HGAS) are developed to solve the models. Numerical experiments evaluating the efficiency of the algorithms showed that the HGAS method performed better than the GA. Also observed is that the crisp model's average total costs were lower than those of the fuzzy model. The results as a whole indicate that the models can evaluate the performance of contracts and optimize cooperative green supply chain management. Highlights • We formulate two NIP models for GSCM with GHG emissions constraints, assuming constant and fuzzy demand, respectively. • The extension principle is used to apply the fuzzy set theory to the fuzzy model. • GA and HGAS methods are proposed. • HGAS performs better than GA in accuracy. • The total cost of GSCM is changing in accordance with the upper limit of GHG emissions. [ABSTRACT FROM AUTHOR]

Abstract: It is common practice in many industries to use a replenishment contract with a mechanism of capacity reservation. In this paper, we focus on a multi-period capacity reservation contract practiced between a buyer, who buys a single type of product and sells it to end-customers, and two or more heterogeneous suppliers, who produce and replenish the product as agreed upon contractually. In this paper, a mathematical model including several key features of a real contract is developed for a single supplier situation from the buyer’s perspective. It is then extended to a multiple supplier model for a system in which there are several heterogeneous suppliers with different capacities and prices. A rolling-horizon implementation strategy is suggested for the efficient application of the models. Extensive computational experiments demonstrate that the model and strategy can produce cost effective contractual terms for the buyer within a few seconds. [Copyright &y& Elsevier]

Abstract: Endovascular embolization has been regarded as the primary treatment for dural arteriovenous fistula (dAVF). The aim of this study was to describe our experience with treatment and outcomes for patients with dural AVF, and to determine optimal treatment modalities. Between November 2007 and March 2011, 43 patients with dAVF (14 cavernous sinus, 20 transverse-sigmoid sinus, and nine patients with other types) were admitted to our Institute for treatment. For cavernous sinus dAVF, transvenous embolization was attempted as the first-line treatment with residual AVF obliterated by transarterial embolization (TAE), except for three patients who were treated conservatively. For transverse-sigmoid sinus dAVF, TAE was the primary treatment method. Nine of 14 (64.3%) patients with cavernous sinus dAVF had complete angiographic resolution. For transverse-sigmoid sinus dAVF, 14 of 17 (82.4%) patients were treated by TAE using Onyx Liquid Embolic System (eV3 Neurovascular, Irvine, CA, USA). Nine of these patients (64.3%) were angiographically cured or improved clinically with no serious complications, and the other five (35.7%) patients showed significant reductions in arteriovenous shunt. The other nine dAVF were treated by TAE or surgical disconnection depending upon the accessibility of the lesion and risk of complications. Six of nine (66.7%) patients had complete angiographic obliteration or clinical improvement. With developments in diagnostic tools and endovascular interventions, dAVF have become an important neurovascular issue. The results of this study suggest that a new approach to treatment of dAVF is needed. [Copyright &y& Elsevier]

Abstract: We analyzed the outcome of posterior fossa decompression accompanied by widening of the cisterna magna, without disturbing the arachnoid, in patients with Chiari I malformation (CMI) associated with syringomyelia. Twenty-five adult patients with CMI and syringomyelia, who underwent surgery between October 2000 and December 2008, were enrolled in this study. All patients underwent foramen magnum decompression with C1 decompression, with or without C2 decompression. Three surgeons performed a dura opening with duraplasty in 20 patients, and another surgeon excised the outer layer of the dura without duraplasty in five patients. Clinical and radiological assessments were performed preoperatively and during the follow-up period. After surgery, 20 (80%) patients achieved a significant improvement in their clinical symptoms. However, four patients (16%) achieved only a stable state, and one patient’s symptoms worsened. Radiological analysis showed that 17 patients (68%) had a favorable result; that is, a total collapse, or a marked reduction, of the syrinx. Seven patients (28%) were stable in terms of syrinx size. However, the syrinx enlarged in one patient who had undergone excision of the outer dura. Twenty-four patients achieved a widened cisterna magna with ascent of the cerebellar tonsils into the posterior fossa and acquisition of a more rounded shape. Postoperative complications included a transient headache and vomiting in three patients and transient motor weakness in one patient. Two patients developed a superficial wound infection. This study shows that arachnoid-preserving posterior fossa decompression is a safe and effective treatment for patients with CMI with associated syringomyelia. [Copyright &y& Elsevier]

Objective: To monitor hemodynamic changes using transcranial Doppler (TCD) in patients with an arteriovenous malformation (AVM) after Gamma Knife surgery (GKS). Methods: The study comprised 22 patients (17 men and 6 women, mean age 42 years, range 18–69 years) with an unruptured AVM fed by only the middle cerebral artery (MCA) or its branches. Serial TCD profiles from proximal MCAs were analyzed and correlated with treatment outcome. Results: Baseline TCD measurements (presented as means ± standard deviations) revealed significantly higher mean blood flow velocity (Vm) and lower mean pulsatility index (PI) in MCAs ipsilateral to AVMs than in contralateral MCAs (Vm 102 cm/s ± 29 vs 66 cm/s ± 16, P < 0.05; PI 0.63 ± 0.10 vs 0.84 ± 0.10, P < .05). No correlation was found between AVM volumes and hemodynamic indices. Vm values in ipsilateral MCAs were lower at 6 months (88 cm/s ± 26) after GKS than at baseline (P < 0.05). At 2 years after GKS, a further decrease in mean Vm and an increase in mean PI were observed in ipsilateral MCAs, which then approximated the values of contralateral MCAs (Vm 71 cm/s ± 30 vs 61 cm/s ± 11, P = 0.16; PI 0.76 ± 0.17 vs 0.83 ± 0.14, P = 0.15). Cerebral angiography (CAG) at the same time revealed total obliteration of AVMs in 11 patients. Changes in Vm and PI values were found to be correlated with the completeness of obliteration. However, no correlation was found between baseline TCD measurements and level of obliteration. Conclusions: Normalization of hemodynamic indices measured by TCD was found to be correlated with AVM obliteration after GKS. However, significant hemodynamic improvements may develop after GKS before obvious obliteration by anatomic imaging. [Copyright &y& Elsevier]

Abstract: Despite studies on the use of human embryonic stem cell (hESC) derivatives to treat ischemic diseases, there are technical safety issues that have yet to be resolved. Herein, we sought to develop a method for using secreted angiogenic factors from hESC-derived endothelial cell derivatives (hESC-ECs), while avoiding direct cell incorporation, to reduce tumorigenesis or unidentified side effects of injected cells in vivo. Multicellular aggregation of hESC-ECs (MA-hESC-ECs) increases survivability, and encapsulation in Matrigel (EnMA-hESC-ECs) blocks the cells’ in vivo migration. To examine the therapeutic effects of EnMA-hESC-ECs, we implanted both forms of hESC-ECs in a mouse model of hindlimb ischemia. Treatment with EnMA-hESC-ECs suppressed limb loss and tissue damage with no noticeable side effects, such as tumorigenesis or teratoma formation, and the Matrigel implant could be easily removed after the procedure. Thus, MA and the encapsulation system are effective techniques for utilizing humoral factors secreted by hESC derivatives that aid in the survivability and safety. We expect these results to contribute to the thriving stem cell field by improving the bioavailability of hESC derivatives for regenerative medicine. [Copyright &y& Elsevier]

Abstract: The low frequency current ripple in grid-connected fuel cell systems is generated from dc–ac inverter operation, which generates 60 Hz fundamental component, and gives harmful effects on fuel cell stack itself, such as making cathode surface responses slower, causing an increase of more than 10% in the fuel consumption, creating oxygen starvation, causing a reduction in the operating lifetime, and incurring a nuisance tripping such as overload situation. With these reasons, low frequency current ripple makes fuel cell system unstable and lifetime of fuel cell stack itself short. This paper presents a fast and robust control algorithm to eliminate low frequency current ripple in grid-connected fuel cell systems. Compared with the conventional methods, in the proposed control algorithm, dc link voltage controller is shifted from dc–dc converter to dc–ac inverter, resulting that dc–ac inverter handles dc link voltage control and output current control simultaneously with help of power balancing technique. The results indicate that the proposed algorithm can not only completely eliminate current ripple but also significantly reduce the overshoot or undershoot during transient states without any extra hardware. The validity of the proposed algorithm is verified by computer simulations and also by experiments with a 1 kW laboratory prototype. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to examine the clinical characteristics and angiographic findings of spontaneous idiopathic subarachnoid hemorrhage (ISAH) and to compare these with those of aneurysmal SAH (ASAH). We retrospectively reviewed the clinical characteristics and venograms of 118 consecutive patients with ISAH during the past 10years for possible abnormalities in venous structures. Also, 57 patients with ASAH during the past 4years were examined. Patients with ISAH showed low frequency of hypertension and no patient suffered from an episode of re-bleeding, or delayed ischemic deficits. Physical actions, including varieties of the Valsalva maneuver, were the causes of ISAH in 17 (29.8%) patients. Compared with patients with ASAH, patients with ISAH showed a significant difference in the drainage patterns of the basal vein of Rosenthal (BVR) (p =0.001). In addition, whereas a linearly decreasing trend toward the primitive type was evident in ASAH, each drainage pattern was distributed evenly in ISAH (linear by linear association, p =0.000). In this study, the primitive drainage pattern of BVR has a relationship with ISAH compared to ASAH. The way in which this venous configuration might influence bleeding remains unknown. [ABSTRACT FROM AUTHOR]

Abstract: We investigated surgical results based on craniotomy sidedness in patients with superiorly projecting anterior communicating artery (ACoA) aneurysms to evaluate decision-making on the surgical approach based on the anatomical planes of both A2 vessels. Among 99 patients treated surgically, 19 (19.2%) ACoA aneurysms projected superiorly. We analyzed the associations between surgical outcomes and the planes containing both A2 vessels (anterior or posterior displacement of A2 in relation to the aneurysm). Surgery in nine patients was approached from the side of the A2 posterior displacement, while surgery for ten patients was approached from the side of anterior displacement. A higher requirement for gyrus rectus aspiration was found in patients approached from the plane of A2 anterior displacement (p =0.041). All aneurysms were successfully secured without any surgery-related complications, except in two patients. Approaches from the side of posterior displacement of A2 in patients with superiorly projecting ACoA aneurysm allowed the aneurysmal necks to be secured safely and prevented postoperative complications. [Copyright &y& Elsevier]

Abstract: In Part 1 of this study, an advanced numerical simulation method was proposed to investigate the impact characteristics of the KN-18 spent nuclear fuel (SNF) transport cask recently developed in Korea and verified against the experimental results. In this study, sensitivity analyses are carried out using the proposed numerical simulation method to investigate the effects of the various modeling and design parameters, such as material model assumption, modeling methodology, analytical assumptions, and design variables that can affect the impact characteristics of a cask and the accuracy of the numerical results. These parametric analyses were also performed to provide a basis for correlations with test results that is closer to reality than merely conservative as a means of benchmarking the numerical models. In addition, the parametric analysis results are compared against the experimental results, and the sensitivities of each parameter are summarized to provide references for the future design and analysis of SNF transport casks. [Copyright &y& Elsevier]

Abstract: Domestic and international regulations for the transportation of radioactive materials strictly prescribe the design requirements for spent nuclear fuel (SNF) transport casks. According to the applicable codes, a transport cask must withstand a free-drop impact of 9m onto an unyielding surface and a free-drop impact of 1m onto a mild steel bar. However, the structural performance of a transport cask is not easy to evaluate precisely because the dynamic impact characteristics of the cask, which includes impact limiters to absorb the impact energy, are so complex. In this study, a more advanced and applicable numerical simulation method using the finite element (FE) method via the commercial FE code LS-DYNA is proposed and verified against the experimental results for a 1/3-scale model of the KN-18 SNF transport cask, recently developed in Korea. In addition, the detailed dynamic impact characteristics of the transport cask under free-drop conditions are investigated via the proposed numerical simulation method and actual drop tests to improve the accuracy and optimization of the SNF transport cask design. [Copyright &y& Elsevier]

Summary: The aim of this study is to determine surgical outcomes and factors affecting seizure outcomes in patients who harbor supratentorial cavernous angiomas presenting with seizures. Sixty patients were classified into the intractable epilepsy group (n =22) and the sporadic seizure group (n =38) and then managed differently in accordance with our guidelines. Patients exhibiting sporadic seizures were treated by lesionectomy, except for patients harboring mesial temporal lesions. We performed lesionectomy, extended lesionectomy, standard temporal lobectomy and tailored resection on 33, 9, 9 and 9 patients, respectively. Finally, 72.7% (16/22) of patients with intractable epilepsy and 89.5% (34/38) of patients with sporadic seizures achieved Engel Class I outcomes. A long duration of illness was somewhat related to a poor outcome in patients with intractable epilepsy, yet this was not true of patients with sporadic seizures. Other factors which included age at onset, size of the lesions and locations were not related to seizure outcomes. The role of residual hemosiderin is yet to be discovered. A lesionectomy alone can be considered a reasonable approach for those patients who exhibit sporadic seizures and have an extra-temporal or neo-temporal lesion. In patients with intractable epilepsy and/or mesial temporal lesions, a more invasive approach could achieve the better seizure outcome. [Copyright &y& Elsevier]

Abstract: We consider the problem of determining the initial spare inventory level for a multi-echelon repairable item inventory system. We extend the previous results to the system, which has an inventory at the central depot as well as at bases and with a general repair time distribution. We propose an algorithm which finds spare inventory level to minimize the total expected cost and simultaneously to satisfy a specified minimum service rate. Extensive computational experiments show that the algorithm is accurate and efficient. [Copyright &y& Elsevier]

Abstract: Surgical clipping is preferred to endovascular coil embolization for the treatment of middle cerebral artery (MCA) aneurysms. The aim of this study was to describe our experience of coiling for MCA aneurysms, to analyze the reasons for choosing coiling instead of clipping, and to evaluate the appropriateness of the choice. We retrospectively reviewed data of 30 patients who had coiling for MCA aneurysms in our Institute from January 2008 to February 2011. We analyzed the morphologies, techniques, angiographic results and complications of 30 aneurysms treated with coiling, and compared the outcomes with those of 78 clipped aneurysms during the same period. The most common reason for choosing coiling instead of clipping was the short length of the M1 artery (17/30, 56.7%). Complete obliteration of the aneurysm was achieved in 28 of 30 coiling patients (93%) and in 72 of 78 clipping patients (92%). In the coiling group, two of 30 patients (6.7%) had post-procedural infarctions on radiologic evaluation, with only one infarction in clinically relevant territory. There was one intra-procedural rupture and one aneurysm recanalization requiring retreatment in the coiling group. In the clipping group, two infarctions, one subdural hygroma and two intracerebral hematomas were found as postoperative complications, with two clinical deteriorations. Endovascular coil embolization should be considered for treatment of MCA aneurysms as it has angiographic results equivalent to surgical clipping and acceptable post-procedural complications. It is particularly appropriate for patients with serious medical problems or where there is the risk of damaging perforating lenticulostriate arteries on the MCA during surgery. [Copyright &y& Elsevier]

This study aimed to evaluate the clinical course after flow diversion (FD) treatment with a focus on aneurysms with remnant sac filling, by analyzing angiographic outcomes, aneurysm volume, and clinical events. We retrospectively reviewed the medical records of 61 patients who underwent FD for intracranial aneurysms between July 2014 and June 2021. The majority of aneurysms (52.5%) were located in the internal carotid artery, with a median diameter of 16.6 mm and neck size of 9.3 mm. Remnant filling was observed in 17 aneurysms (27.9%) more than 18 months after FD, 10 (16.4%) of these aneurysms underwent enlargement, which occurred only in cases with subtotal filling or entry remnant states. Eleven patients experienced major adverse events, and three exhibited unfavorable functional outcomes. The incidence of major adverse events and unfavorable functional outcomes was significantly higher in the aneurysm enlargement group than that in the no-filling or stable remnant filling groups (P < 0.001). Aneurysmal diameter and the presence of incorporated branches were independent predictors of aneurysm enlargement, while the presence of incorporated branches was the only independent predictor of persistent remnant filling. Aneurysm enlargement after FD is not uncommon, particularly when the aneurysm is large, has incorporated vessels, or does not undergo occlusion within 12 months, often culminating in major adverse events and unfavorable functional outcomes. In addition to investigating angiographic results, it is necessary to evaluate the changes in aneurysm size and clinical events when assessing the efficacy of FD. [ABSTRACT FROM AUTHOR]

Abstract The interpretation of Large Hadron Collider (LHC) data in the framework of Beyond the Standard Model (BSM) theories is hampered by the need to run computationally expensive event generators and detector simulators. Performing statistically convergent scans of high-dimensional BSM theories is consequently challenging, and in practice unfeasible for very high-dimensional BSM theories. We present here a new machine learning method that accelerates the interpretation of LHC data, by learning the relationship between BSM theory parameters and data. As a proof-of-concept, we demonstrate that this technique accurately predicts natural SUSY signal events in two signal regions at the High Luminosity LHC, up to four orders of magnitude faster than standard techniques. The new approach makes it possible to rapidly and accurately reconstruct the theory parameters of complex BSM theories, should an excess in the data be discovered at the LHC. [ABSTRACT FROM AUTHOR]

Human and mouse embryonic stem cells (ESCs) differ in terms of their pluripotency status, i.e., naïve vs. primed. This affects various biological properties and leads to several technical hurdles for future clinical applications, such as difficulties in chimera formation, single-cell passaging, and gene editing. In terms of generating functional human tissues and organs via mammalian interspecies chimerism, a fluorescent chemical probe that specifically labels naïve ESCs would help to isolate these cells and monitor their conversion. This study demonstrates that the fluorescent chemical probe compound of designation yellow 9 (CDy9) selectively stains naïve, but not primed, mouse ESCs (mESCs). CDy9 entered cells via Slc13a5, a highly expressed membrane transporter in naïve mESCs. Fluorescence-based cell sorting based on CDy9 staining successfully separated naïve mESCs from primed mESCs. Mice generated using CDy9 + cells isolated during the conversion of mouse epiblast stem cells into naïve mESCs exhibited coat color chimerism. Furthermore, CDy9 specifically stained cells in the inner cell mass of mouse embryos. These findings suggest that CDy9 is a useful tool to isolate functional naïve mESCs. [ABSTRACT FROM AUTHOR]

Abstract: A 51-year-old female presented with bilateral accessory middle cerebral arteries (MCA) with associated ruptured aneurysm manifesting as a subarachnoid hemorrhage. Angiography demonstrated the bilateral accessory MCA and associated ruptured aneurysm at the junction of the left anterior cerebral artery and left accessory MCA. This was successfully treated by coil embolization. Magnetic resonance angiography obtained 6 months later revealed no evidence of residual or recurring aneurysm. [Copyright &y& Elsevier]

Objective We sought to identify the clinical outcome and predictors for ischemic stroke recurrence in adults with symptomatic moyamoya disease (MMD). Methods We analyzed 104 adult MMD patients with ischemic stroke or TIA registered at our institution. All patients underwent digital subtraction angiography and single photon emission computed tomography to measure disease severity and cerebral vascular reserve (CVR). A Cox regression model was used to identify predictors of recurrent ischemic stroke. Results Fifty-nine patients were non-surgically treated and 45 patients were surgically treated. In the non-surgical group, the Kaplan–Meier estimate of ischemic stroke recurrence was 1.6% in the first year and 11.8% in the 5th year. Hypertension (hazard ratio [HR] = 0.07, 95% confidence interval [CI] 0.01–0.99), diabetes (HR = 35.16, 95% CI 2.61–474.16), presence of steno-occlusive lesion in posterior cerebral arteries (HR = 17.53, 95% CI 2.02–152.43), and extended or global decreased CVR (HR = 13.62, 95% CI 1.55–119.84) were independent predictors of recurrence. In the surgical group, the Kaplan–Meier estimate of ischemic stroke recurrence was 24.4% in the first year and 24.4% in the 5th year. Half of the recurred patients experienced recurrent ischemic strokes postoperatively. Diabetes was the only predictor of recurrent ischemic stroke (HR = 6.17, 95% CI 1.31–29.14). Conclusions In non-surgically treated MMD, PCA stenosis and CVR were identified as predictors of ischemic stroke recurrence. Diabetes was an independent predictor of recurrent ischemic stroke in both non-surgical and surgically treated MMD groups. [ABSTRACT FROM AUTHOR]

Ethmoidal dural arteriovenous fistula (DAVF) is a rare type of intracranial DAVF. The aim of this study was to report our experience with a unilateral approach and discuss its effectiveness for ethmoidal DAVF treatment. The study included 19 patients who underwent surgical treatment for ethmoidal DAVF between January 1999 and May 2021. Median age of patients was 59.7 years; 16 (84%) patients were male. Three patients had a ruptured ethmoidal DAVF. Preoperative digital subtraction angiography showed that all ethmoidal DAVFs were supplied by the bilateral external carotid artery branches. In 18 (95%) patients, cortical draining veins were located on the unilateral side. Bilateral lesions were identified in only 1 (5%) patient. The frontobasal approach was performed in 5 patients (26%), the pterional approach was performed in 5 (26%) patients, and the lateral supraorbital approach was performed in 9 (47%) patients; median procedural times were 198 minutes, 172 minutes, and 111 minutes, respectively. Cortical draining vein was successfully disconnected in all 19 patients with 20 ethmoidal DAVFs. Complete obliteration of ethmoidal DAVF was confirmed in all patients, with no postoperative complications. No recurrence or related clinical events were reported in 13 (68%) patients over 12 months of clinical and radiological follow-up. We reconfirmed excellent outcomes of surgical treatment for ethmoidal DAVFs. Three different surgical strategies were attempted, and each had pros and cons. The lateral supraorbital approach is an efficient surgical option for unilateral ethmoidal DAVFs. Careful preoperative examination for the presence of bilateral drainage is essential. [ABSTRACT FROM AUTHOR]