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1.
The use of field robots can greatly decrease the amount of time, effort, and associated risk compared to if human workers were to carryout certain tasks such as disaster response. However, transportability and reliability remain two main issues for most current robot systems. To address the issue of transportability, we have developed a lightweight modularizable platform named AeroArm. To address the issue of reliability, we utilize a multimodal sensing approach, combining the use of multiple sensors and sensor types, and the use of different detection algorithms, as well as active continuous closed‐loop feedback to accurately estimate the state of the robot with respect to the environment. We used Challenge 2 of the 2017 Mohammed Bin Zayed International Robotics Competition as an example outdoor manipulation task, demonstrating the capabilities of our robot system and approach in achieving reliable performance in the fields, and ranked fifth place internationally in the competition.  相似文献   
2.
A technique to determine a trace amount of hydrogen in carbon materials heat-treated above 1000 °C was developed. Three types of carbons prepared from poly(furfulyl alcohol), poly(vinyl chloride) and mesophase carbon microbeads were heat-treated at various temperatures ranging from 1000 to 1800 °C. Then they were gasified by O2 in a fixed bed flow reactor, and the H2O gases formed during the gasification processes were carefully monitored with a Karl Fischer moisture analyzer. As a result, this method makes it possible to determine the hydrogen contents in the carbons down to three places of decimals as a weight percent and can detect even a trace amount of hydrogen as low as 0.002 wt.%. A possible chemical structure of carbon edge sites was also discussed based on the experimentally determined hydrogen contents.  相似文献   
3.
Traumatic injuries of arteries lead to acute bleeding or ischemia. In the hand, which is perfused by two arteries, this symptom could be missed. The hypothenar hammer syndrome is a traumatic occlusion of the distal arteria ulnaris. Dependent on the mechanism of the trauma the clinical symptoms may appear late. A specific angiographic or duplex sonographic diagnostic investigation is necessary to show the arterial occlusion. There is no proven therapeutic procedure. Exact diagnosis of the occlusion as an effect of the trauma is important for the patient and is the basis of any therapeutic intervention.  相似文献   
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Phosphoinositides (PIs) play important roles in the structure and function of the brain. Associations between PIs and the pathophysiology of schizophrenia have been studied. However, the significance of the PI metabolic pathway in the pathology of schizophrenia is unknown. We examined the expression of PI signaling-associated proteins in the postmortem brain of schizophrenia patients. Protein expression levels of phosphatidylinositol 4-phosphate 5-kinase type-1 gamma (PIP5K1C), phosphatidylinositol 4-kinase alpha (PIK4CA, also known as PIK4A), phosphatase and tensin homolog deleted from chromosome 10 (PTEN), protein kinase B (Akt), and glycogen synthase kinase 3β (GSK3β) were measured using enzyme-linked immunosorbent assays and multiplex fluorescent bead-based immunoassays of the prefrontal cortex (PFC) of postmortem samples from 23 schizophrenia patients and 47 normal controls. We also examined the association between PIK4CA expression and its genetic variants in the same brain samples. PIK4CA expression was lower, whereas Akt expression was higher, in the PFC of schizophrenia patients than in that of controls; PIP5K1C, PTEN, and GSK3β expression was not different. No single-nucleotide polymorphism significantly affected protein expression. We identified molecules involved in the pathology of schizophrenia via this lipid metabolic pathway. These results suggest that PIK4CA is involved in the mechanism underlying the pathogenesis of schizophrenia and is a potential novel therapeutic target.  相似文献   
6.
To identify nitrobenzanthrones (NBAs) such as 3-nitro-7 H -benz[ de ]anthracene-7-one (3-NBA) on the basis of their electronic spectral data, we have synthesized 1-, 2-, 3-, 9-, and 10-NBAs and measured their absorption and emission spectra. The first strong absorption band of the NBAs appeared in the region 350-440 nm; the band of 10-NBA was red-shifted by about 20 nm. The molar absorptivities of 3- and 9-NBA were about two times as large as those of the others. The fluorescence spectra of the NBAs varied more largely with the position of the nitro group compared to the absorption spectra. The quantum yields of fluorescence were very small, ranging from ~10 m 2 for 2- and 10-NBA to ~10 m 4 for 1- and 3-NBA. 3-NBA exhibited a characteristic spectrum with two broad bands at 450 and 530 nm. On excitation causing an n ~ * transition in the NBAs, their fluorescence intensities increased by a factor of 10. Phosphorescence was observed at 77 K for all compounds though that of 1-NBA was very weak. These results give the promise of characterizing individual isomers of NBAs on the basis of their spectroscopic data.  相似文献   
7.
In this study, we report on our simulation and experimental results for quasi-one junction SQUIDs (QOS) comparator targeted to be used in the front-end of the detector read-out circuits. The QOS is used as a 1-bit quantizer in the front-end of the read-out circuit. Their performance and reliability is very much depending on the circuit parameters of the QOSs. The main design parameters are the threshold level, gray zone width, and the chip-to-chip reproducibility over different fabrication batches. For some special applications, such as detector readout, the overall power consumption needs to be sufficient small. We measured threshold and gray zone counting each individual switching event for various bias and input current values and for different QOS designs. In addition, circuit simulations including thermal noise are used to explain the observed circuit behavior and to optimize design parameters.  相似文献   
8.
OBJECTIVE: The clinical characteristics and outcomes of endometrial cancer patients 45 years of age and younger were compared with those of patients older than 45 years of age. METHODS: We performed a cross-sectional study of 301 consecutive endometrial cancer patients referred to our center from 1989 to 1994. Of the 289 patients eligible for study, 40 were 45 years of age or younger (group A) and 249 were older than 45 years of age (group B). RESULTS: The majority of patients in both groups presented with stage I disease. Of the women with stage I disease, patients in group A were more likely than those in group B to have low-grade disease localized to the endometrium (P < .001; relative prevalence 3.39; confidence interval [CI] 1.88, 6.12). However, the distribution of stages I to IV overall was the same for the two groups (P = .269). Although univariate analysis revealed that 11% of the patients in group A and 2% in group B had synchronous ovarian malignancies (P = .007; relative prevalence 5.42; CI 1.39, 21.14), multivariate logistic regression found that nulliparity, not age, was an independent risk factor for synchronous ovarian malignancy (P = .017; relative prevalence 6.15; CI 1.52, 25.61). There were no statistically significant differences by age in the prevalence of high-risk endometrial histology (serous and clear cell carcinoma) or in survival. CONCLUSION: The overall distribution of tumor stage and survival were the same for the younger and older women; this finding contradicts previous reports that suggest that young women with endometrial cancer are at lower risk. Additionally, nulliparity, which occurs with a higher prevalence in younger women who develop endometrial cancer, is associated statistically with the development of synchronous ovarian malignancies.  相似文献   
9.
In this study, two deposition methods (i.e. MOCVD and sputtering methods) to prepare n-type ZnO window layers for CIGS-based thin-film solar cells are discussed. In order to make ZnO : Al transparent conductive oxide (TCO) films prepared by DC magnetron sputtering comparable to ZnO : B TCO prepared by MOCVD, a new ZnO sputtering process is proposed by introducing a multilayer structure. Using these films, CIGS thin-film solar cells with efficiencies of greater than 14% have been fabricated with an active area of 3.2 cm2. This structure was adapted to fabricate CIGS thin-film mini-modules with efficiencies around 11% having aperture area of 50 cm2.  相似文献   
10.
The possibility of detecting the passage of emboli through the carotid artery via skin electrodes is investigated. Impedance changes calculated using both finite-element and theoretical methods indicate that detection of emboli in vivo should be possible.  相似文献   
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