Concept and Feasibility Evaluation of Distributed Sensor-Based Measurement Systems Using Formation Flying Multicopters

Unmanned aerial vehicles (UAVs) have been used for increasing research applications in atmospheric measurements. However, most current solutions for these applications are based on a single UAV with limited payload capacity. In order to address the limitations of the single UAV-based approach, this paper proposes a new concept of measurements using tandem flying multicopters as a distributed sensor platform. Key challenges of the proposed concept are identified including the relative position estimation and control in wind-perturbed outdoor environment and the precise alignment of payloads. In the proposed concept, sliding mode control is chosen as the relative position controller and a gimbal stabilization system is introduced to achieve fine payload alignment. The characterization of the position estimation sensors (including global navigation satellite system and real-time kinematics) and flight controller is carried out using different UAVs (a DJI Matrice M600 Pro Hexacopter and Tarot X4 frame based Quadcopter) under different wind levels. Based on the experimental data, the performance of the sliding mode controller and the performance of the gimbal stabilization system are evaluated in a hardware-in-the-loop simulation environment (called ELISSA). Preliminary achievable control accuracies of the relative position and attitude of subsystems in the proposed concept are estimated based on experimental result

Altered myelination in the Niemann-Pick type C1 mutant mouse

Niemann–Pick type C1 (NPC1) disease is a lysosomal storage disorder caused by mutation of Npc1 or Npc2 gene, resulting in various progressive pathological features. Myelin defection is a major pathological problem in Npc1 mutant mice; however, impairment of myelin proteins in the developing brain is still incompletely understood. In this study, we showed that the expression of myelin genes and proteins is strongly inhibited from postnatal day 35 onwards including reduced myelin basic protein (MBP) expression in the brain. Furthermore, myelination characterized by MBP immunohistochemistry was strongly perturbed in the forebrain, moderately in the midbrain and cerebellum, and slightly in the hindbrain. Our results demonstrate that mutation of the Npc1 gene is sufficient to cause severe and progressive defects in myelination in the mouse brain

N-Cadherin Upregulation Promotes the Neurogenic Differentiation of Menstrual Blood-Derived Endometrial Stem Cells

Peripheral nerve injuries are typically caused by either trauma or medical disorders, and recently, stem cell-based therapies have provided a promising treatment approach. Menstrual blood-derived endometrial stem cells (MenSCs) are considered an ideal therapeutic option for peripheral nerve repair due to a noninvasive collection procedure and their high proliferation rate and immunological tolerance. Here, we successfully isolated MenSCs and examined their biological characteristics including their morphology, multipotency, and immunophenotype. Subsequent in vitro studies demonstrated that MenSCs express high levels of neurotrophic factors, such as NT3, NT4, BDNF, and NGF, and are capable of transdifferentiating into glial-like cells under conventional induction conditions. Moreover, upregulation of N-cadherin (N-cad) mRNA and protein expression was observed after neurogenic differentiation. In vivo studies clearly showed that N-cad knockdown via in utero electroporation perturbed the migration and maturation of mouse neural precursor cells (NPCs). Finally, a further transfection assay also confirmed that N-cad upregulation in MenSCs results in the expression of S100. Collectively, our results confirmed the paracrine effect of MenSCs on neuroprotection as well as their potential for transdifferentiation into glial-like cells and demonstrated that N-cad upregulation promotes the neurogenic differentiation of MenSCs, thereby providing support for transgenic MenSC-based therapy for peripheral nerve injury

Thin-walled Cystic Lung Cancer: An Analysis of 24 Cases and Review of Literatures

Background and objective Lung cancer presenting as cystic lesions was first described by Anderson and Pierce in 1954. Lung cancer presenting as cysts is a rare entity in clinical practice. Differential diagnosis is difficult in the benign-like cyst. This study investigated the clinical characteristics, diagnosis and treatment of lung cancer presenting as cysts. Methods We conducted a retrospective analysis of the clinical records of 24 patients who underwent surgery for a primary lung cancer presenting as cysts in our department between 2007 and 2013. We defined a ‘Thin-walled cyst’ as a cavitary lesion with a wall thickness of 4 mm or less along at least 75% of the circumference of the lesion. The whole group underwent post-operative follow-up. Results The incidence of cystic lung cancer was 0.49% (24/4,897) of surgical cases. The subjects’ age ranged from 19 to 77 yr with a median age of 56.5 yr. Ten cases presented with respiratory symptoms while 14 showed abnormal shadows on a chest CT without symptoms. Histological analysis showed that 18 cases were of adenocarcinoma, three of squamous cell carcinoma, one of small cell carcinoma, one of adenosquamous carcinoma and one of large cell carcinoma. Three patients were dead, and the remaining 21 patients are alive and disease free at the end of follow-up. Conclusion Cystic lung cancer should be kept in mind during the differential diagnosis of focal benign cyst. Cystic lung cancer could achieve a good outcome if early diagnose can be obtained

When Ultimate Adhesive Mechanism Meets Ultimate Anti‐Fouling Surfaces—Polydopamine Versus SLIPS: Which One Prevails?

What happens when the extremely adhesive and versatile chemistry of polydopamine (PDA) is in contact with the extremely slippery surfaces known as slippery liquid‐infused porous substrates (SLIPS)? Inspired by the pitcher plant, SLIPS possess excellent repellence against a variety of complex liquids and have been proposed as promising antifouling surfaces because of their successful performance even in marine environments. In the counterpart, inspired by the adhesive proteins enabling the strong adhesion of mussels to multiple substrates, PDA has been extensively studied for its ability to adhere on nearly every type of substrate. The interaction between various SLIPS systems and the highly fouling medium from the oxidative polymerization of dopamine is explored here. A PDA coating is observed on all the SLIPS evaluated, modifying their hydrophobicity in most cases. In‐depth study of silicone‐based SLIPS shows that hydrophobicity of PDA coated SLIPS partially recovers with time due to percolation of the lubricant through the coating. “Strongly” bound PDA species are attributed to the formation of dopamine‐polydimethylsiloxane species on the crosslinked matrix, rendering a coating that withstands repeated washing steps in various solvents including water, hexane, and toluene. The results not only satisfy scientific curiosity but also imply a strategy to modify/bond SLIPS