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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.
Oda  Yayoi  Abe  Tsuneyuki  Takano  Ruriko  Tatsuta  Amane  Nakamura  Minoru 《Behaviormetrika》2007,34(1):45-57

By using structural equations, we investigated the effect of chronic stress on salivary cortisol rhythm and proposed a causal model of chronic stress by using psychosocial and physiological data. First, 111 healthy workers (48 males, 63 females) completed questionnaires on chronic stress and lifestyle habits. Then, they provided saliva samples and answered questionnaires that were prepared to assess their psychological states 5 times (on waking up and at 10:00, 11:40, 14:00, and 16:00) on workdays. Structural equation modeling (SEM) revealed that chronic stress and longer commuting time resulted in sleep irregularities and this disrupted the cortisol circadian rhythm. This suggests that chronic stress disrupts the cortisol circadian rhythm even in healthy individuals, and sleep regularity mediates the effect of chronic stress on the cortisol rhythm.

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3.
The major envelope protein, p35, of vaccinia virus (VV; strain LIVP) was purified by extraction from virions with the non-ionic detergent Nonidet P-40. The protein was cleaved with CNBr. Four homogeneous peptides were isolated and their N-terminal amino-acid (aa) sequences determined. A computer search of a protein sequence databank revealed complete identity of the determined sequences with aa 44-63, 144-149, 154-165 and 224-238 of ORF H3 of the HindIII-H fragment of the VV genome [Rosel et al., J. Virol. 60 (1989) 436-446]. Earlier, Gordon et al. [Virology 167 (1988) 361-369] determined that the p35 surface protein of VV strain IHD-W is encoded by the H6 gene. Muravlev et al. [Biopolymery i kletka 6 (1990) 83-89 (Russian)] deduced from their data that gene A2 encodes this prominent antigen. Taking into account this ambiguity, we cloned the genes H3, H6 and A2 in expression vectors, prepared the specific antisera against the expression products and conducted the immunochemical analysis of the recombinant and native VV-specific proteins. It has been established that the H6 codes for an early protein that is found only in the infected cell extracts, but is absent in mature virions. The immunodominant protein p35 of VV strain LIVP is encoded by the gene H3. The gene A2 protein product is present mainly in the infected cell extract, but the antiserum against the A2 product shows a rather weak interaction with the 35-kDa fraction of structural VV proteins resolved by electrophoresis.  相似文献   
4.
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   
5.
The pore-forming alpha 1 subunit of L-type calcium (Ca2+) channels is the molecular target of Ca2+ channel blockers such as phenylalkylamines (PAAs). Association and dissociation rates of (-)devapamil were compared for a highly PAA-sensitive L-type Ca2+ channel chimera (Lh) and various class A Ca2+ channel mutants. These mutants carry the high-affinity determinants of the PAA receptor site in a class A sequence environment. Apparent drug association and dissociation rate constants were significantly affected by the sequence environment (class A or L-type) of the PAA receptor site. Single point mutations affecting the high-affinity determinants in segments IVS6 of the PAA receptor site, introduced into a class A environment, reduced the apparent drug association rates. Mutation I1811M in transmembrane segment IVS6 (mutant AL25/-I) had the highest impact and decreased the apparent association rate for (-)devapamil by approximately 30-fold, suggesting that this pore-lining isoleucine in transmembrane segment IVS6 plays a key role in the formation of the PAA receptor site. In contrast, apparent drug dissociation rates of Ca2+ channels in the resting state were almost unaffected by point mutations of the PAA receptor site.  相似文献   
6.
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   
7.
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   
8.
Fas-mediated apoptosis has been shown to be mediated by the IL-1beta converting enzyme (ICE) pathway. To determine the relationship between ICE and its substrate IL-1beta, we examined six human cell lines for susceptibility to Fas-mediated apoptosis and Fas induction of ICE-like activity. The human B lymphoblastoid cell line SKW6.4 and the human T lymphoma cell lines Jurkat, CEM-6, H-9, and MOLT4 were susceptible to Fas-mediated apoptosis, whereas the human promyelocytic leukemia cell line HL-60 was resistant to Fas-mediated apoptosis. ICE mRNA was highly expressed in SKW6.4, H-9, and HL-60 cells, and ICE-like activity increased during Fas-mediated apoptosis in SKW6.4 cells. In contrast, IL-1beta mRNA was highly expressed only in HL-60 cells. Acetyl-Tyr-Val-Ala-Asp-chloromethylketone, a tetrapeptidyl inhibitor of ICE, prevented Fas-mediated apoptosis strongly in SKW6.4 and H-9 cells but weakly or marginally in other cells. To examine whether intracellular IL-1beta is a proteolytic substrate or an endogenous competitive inhibitor against other substrates for Fas-ICE-mediated apoptosis in SKW6.4 cells, we established precursor IL-1beta transfectant clones using SKW6.4 cells. We demonstrated that stably transfected SKW6.4 cells expressing precursor IL-1beta, but not cells transfected with the empty vector, exhibited resistance to Fas-mediated apoptosis due to competitive inhibition of ICE-like activity, which was associated with increased cleavage of precursor IL-1beta to mature IL-1beta. These results suggest that Fas-mediated apoptosis is mediated by ICE cleavage of proteolytic substrates other than IL-1beta and that IL-1beta is an endogenous inhibitor of Fas-mediated apoptosis.  相似文献   
9.
The effects of baclofen, a gamma-amino-n-butyric acid receptor B agonist, on gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine and how its effects are influenced by selective (M1) and non-selective (M1 and M2) pharmacological blockade of muscarinic receptors were investigated in inbred Wistar rats. Rats were given s.c. injections of 8 mg/kg body wt baclofen with and without 0.5 mg/kg body wt atropine (non-selective M1 and M2 muscarinic receptor antagonist) or 1.0 mg/kg body wt pirenzepine (selective M1 muscarinic receptor antagonist) every other day after a 25 week carcinogen treatment. At week 52 baclofen significantly decreased the incidence of gastric cancers. Concomitant treatment with atropine significantly attenuated the inhibition by baclofen of gastric carcinogenesis, but combined use with pirenzepine had no significant effect on the inhibition by baclofen of gastric carcinogenesis. Baclofen also significantly decreased the labeling index of the antral mucosa. Baclofen plus atropine attenuated the decrease in the labeling index of the antral mucosa due to baclofen, but baclofen plus pirenzepine had no significant effect on the labeling index. These results suggest that the inhibition of gastric carcinogenesis by baclofen is mediated through muscarinic receptors and M2 receptors, but not M1 receptors, are involved in this response.  相似文献   
10.
The conventional methods (CM) of intraarterial (IA) chemotherapy for inflammatory breast cancer were catheterizations from superior epigastric and brachial artery under general anesthesia. Since 1997, we selected the Seldinger's methods (SM) for ten cases of the disease to control local effects and simplify the technique. Complications of the SM were slight, and side effects were equal to those with CM. The postoperative pathological findings of the SM showed the direct effects of chemotherapy to tumor cells (degenerative and necrotic changes) as compared with the embolism-like effects of CM. But the overall histological effects of chemotherapy by SM were almost equal to those for CM. The strong points of the SM were as follows: 1) More selective IA chemotherapy is available, 2) one can find the passage of the aim vessels and no trouble related to catheter, 3) general anesthesia is not necessary, and the techniques are simple, 4) the wounds are not remarkable. The disadvantages are as follows: 1) Patients must rest the day of IA chemotherapy, 2) in 20% of the procedures, one can not search the vessels, and 3) in 4 cases complications of stiffness of Mj or Mn pectral muscles were found. In future, we expect more effective results by dose escalation or combination chemotherapy.  相似文献   
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