Magnetic Reconnection and Associated Particle Acceleration in High-energy Astrophysics

Magnetic reconnection occurs ubiquitously in the universe and is often invoked to explain fast energy release and particle acceleration in high-energy astrophysics. The study of relativistic magnetic reconnection in the magnetically dominated regime has surged over the past two decades, revealing the physics of fast magnetic reconnection and nonthermal particle acceleration. Here we review these recent progresses, including the magnetohydrodynamic and collisionless reconnection dynamics as well as particle energization. The insights in astrophysical reconnection strongly connect to the development of magnetic reconnection in other areas, and further communication is greatly desired. We also provide a summary and discussion of key physics processes and frontier problems, toward a better understanding to the roles of magnetic reconnection in high-energy astrophysics.Comment: 49 pages, 19 figures. Submitted to Space Science Reviews. This is a review paper as an outcome of the 2022 Magnetic Reconnection Workshop in the International Space Science Institut

Strangulated right paraduodenal hernia successfully treated with single-incision transumbilical surgery

Right paraduodenal hernia (RPH) has been recently reported to be treated with laparoscopic surgery. We report a case of strangulated ileus that occurred as a result of RPH treated via a small umbilical incision. An 11-year-old boy presented to our hospital with complaints of sudden upper abdominal pain associated with bilious vomiting and bloody stool. We preoperatively diagnosed the case to be strangulated ileus caused by an internal hernia and thus performed emergency surgery. After the entire small intestine was carefully exteriorized via a small umbilical incision, a strangulated ileus as a result of the internal hernia was observed. A large hernia sac with its orifice on the right side of the jejunal origin was found behind the right mesocolon, on the basis of which the diagnosis of RPH was made. After releasing the strangulation, the ischemic intestine was reperfused. The hernia orifice was closed. All the abovementioned procedures were transumbilically performed. The patient's postoperative course was uneventful. An umbilical approach is useful for treating RPH because of its favorable cosmetic outcome. In addition, manual delivery of the herniated or incarcerated intestine provides a sense of safety compared with operation using forceps during laparoscopic surgery

A case of superior mesenteric artery syndrome developed after pancreatic teratoma resection

A mature teratoma of the pancreas has rarely been reported, and postoperative superior mesenteric artery syndrome (SMAS) is extremely rare in pediatric pancreatic surgery. A 12-year-old girl underwent an enucleation of the large mature teratoma located at the pancreas uncus. Although her postoperative recovery was fair, the bile-stained gastric juice continued draining at a rate of>1.5 l per day for 2 weeks. An upper gastrointestinal series revealed an abrupt disruption with to-and-fro peristalsis at the third portion of the duodenum. Endoscopy revealed an extrinsic pulsatile compression of this third portion. The aortomesenteric angle measured 12° on ultrasonography, which met the criteria for SMAS. The patient underwent a modified transposition procedure, “switching jejunojejunostomy,” on postoperative day 18. The gastrointestinal passage gradually improved, and complete oral intake was established 1 month after the first surgery. It was considered that the clinical symptoms of SMAS were caused by an anatomical deformation after the pancreatic tumor resection. Switching jejunojejunostomy was found to be an acceptable therapeutic option for this condition

A Comprehensive Design Approach for Injectable Manufacturing Processes considering New Technologies and Operational Aspects

An approach is proposed to comprehensively design the injectable manufacturing process considering various options such as batch and continuous operation modes, multi-use and single-use technology (SUT) equipment, and production sequences. The approach comprises four steps: 1) set design objective, 2) obtain base case design, 3) extract characteristic parameters by sensitivity analysis, and 4) obtain deeper understanding by scenario analysis. Modularized models were developed to analyze and evaluate the design alternatives using multiobjective indicators for economic performance and productivity. The approach was demonstrated in a case study. The result indicated that the alternatives using continuous compounding, batch lyophilization, and SUT equipment were the most favorable. Based on the sensitivity analysis and the future development potential, continuous lyophilization was further investigated. The scenario analysis revealed that continuous lyophilization can become competitive or even superior to batch lyophilization because of future technology development and equipment cost reduction

Aldehyde Dehydrogenase 1 (ALDH1) Is a Potential Marker for Cancer Stem Cells in Embryonal Rhabdomyosarcoma.

Cancer stem cells (CSCs) are defined as a small population of cancer cells with the properties of high self-renewal, differentiation, and tumor-initiating functions. Recent studies have demonstrated that aldehyde dehydrogenase 1 (ALDH1) is a marker for CSCs in adult cancers. Although CSCs have been identified in some different types of pediatric solid tumors, there have been no studies regarding the efficacy of ALDH1 as a marker for CSCs. Therefore, in order to elucidate whether ALDH1 can be used as a marker for CSCs of pediatric sarcoma, we examined the characteristics of a population of cells with a high ALDH1 activity (ALDH1high cells) in rhabdomyosarcoma (RMS), the most common soft tissue sarcoma in children. We used the human embryonal RMS (eRMS) cell lines RD and KYM-1, and sorted the cells into two subpopulations of ALDH1high cells and cells with a low ALDH1 activity (ALDH1low cells). Consequently, we found that the ALDH1high cells comprised 3.9% and 8.2% of the total cell population, respectively, and showed a higher capacity for self-renewal and tumor formation than the ALDH1low cells. With regard to chemoresistance, the survival rate of the ALDH1high cells was found to be higher than that of the ALDH1low cells following treatment with chemotherapeutic agents for RMS. Furthermore, the ALDH1high cells exhibited a higher degree of pluripotency and gene expression of Sox2, which is one of the stem cell markers. Taken together, the ALDH1high cells possessed characteristics of CSCs, including colony formation, chemoresistance, differentiation and tumor initiation abilities. These results suggest that ALDH1 is a potentially useful marker of CSCs in eRMS

ALDH1^high cells have a high tumor-initiating ability.

<p>A, Representative image of a tumor-bearing NOD-SCID mouse. (right: ALDH1^<b>high</b> cells, left: ALDH1^<b>low</b> cells). B-D, Immunohistochemical (IHC) staining of the xenograft tumor sections. The sections were stained for hematoxylin, myogenic markers (Desmin (B), Myogenin (C)) and ALDH1 (D). The tumor cells were positive for Desmin and Myogenin while only a few cells were positive for ALDH1, suggesting that the ALDH1^<b>high</b> cells promoted rhabdomyosarcoma and were reconstituted to incorporate the full range of heterogeneity.</p

Comparison of the biopsy specimens obtained before chemotherapy and the resected specimens obtained after chemotherapy.

<p>The biopsy specimen of eRMS obtained prior to chemotherapy (A) and the resected specimens obtained after chemotherapy (B) stained positive for ALDH1 on immunohistochemistry. These specimens were taken from the vagina-originated eRMS tissue of a 1-year-old girl. The specimens resected after chemotherapy exhibited a greater cytoplasmic ALDH1 expression than the primary biopsy specimen.</p

Upregulated mRNA in the ALDH1^high cells.

<p>A quantitative real-time PCR analysis was performed to evaluate the expression levels of ALDH1 (A), stemness markers (B) and ABC transporters (C). The mean ± SE was calculated from triplicate wells of a representative experiment, and the data for one of three independent experiments are shown in the figure. The expression of ALDH1A3, ALDH1B1, ALDH1L2, Sox2 and ABC transporters was significantly higher in the ALDH1^<b>high</b> cells than in the ALDH1^<b>low</b> cells (p<0.01).</p