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排序方式: 共有242条查询结果,搜索用时 15 毫秒
101.
Marmarosh Cheri L.; Gelso Charles J.; Markin Rayna D.; Majors Rebekah; Mallery Coretta; Choi Jaehwa 《Canadian Metallurgical Quarterly》2009,56(3):337
The purpose of this study was to understand how the real relationship (RR) relates to important process and outcome variables from both the clients’ and therapists’ perspectives. Using a sample of 31 therapist/client dyads at a university counseling center, the authors examined the RR at the 3rd session of therapy and at termination. The results revealed that client adult attachment avoidance was negatively correlated with client RR, while client adult attachment anxiety was uncorrelated. Therapists’ ratings of negative transference were negatively correlated with therapist-rated RR and were uncorrelated with client-rated RR. Hierarchical linear modeling analyses were conducted to predict postintervention outcome from client and therapist perceptions of the RR. Therapists’ ratings of the RR accounted for a significant amount of variance in client posttreatment symptoms while controlling pretreatment symptoms. Client-rated RR total scores and client and therapist 3rd-session alliance scores were not significant predictors of postsymptom ratings. Implications of the usefulness of measuring the RR in psychotherapy are discussed, as are recommendations for future study. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Emily Reiser Evans Pallavi Bugga Vishwaratn Asthana Rebekah Drezek 《Materials Today》2018,21(6):673-685
Cancer immunotherapy, or the utilization of the body’s immune system to attack tumor cells, has gained prominence over the past few decades as a viable cancer treatment strategy. Recently approved immunotherapeutics have conferred remission upon patients with previously bleak outcomes and have expanded the number of tools available to treat cancer. Nanoparticles – including polymeric, liposomal, and metallic formulations – naturally traffic to the spleen and lymph organs and the relevant immune cells therein, making them good candidates for delivery of immunotherapeutic agents. Metallic nanoparticle formulations, in particular, are advantageous because of their potential for dense surface functionalization and their capability for optical or heat-based therapeutic methods. Many research groups have investigated the potential of nanoparticle-mediated delivery platforms to improve the efficacy of immunotherapies. Despite the significant preclinical successes demonstrated by many of these platforms over the last twenty years, only a few metallic nanoparticles have successfully entered clinical trials with none achieving FDA approval for cancer therapy. In this review, we will discuss preclinical research and clinical trials involving metallic nanoparticles (MNPs) for cancer immunotherapy applications and discuss the potential for clinical translation of MNPs. 相似文献
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104.
P. C. Main P. H. Beton B. R. Snell A. J. M. Neves J. R. Owers-Bradley L. Eaves M. Davies M. Henini O. H. Hughes S. P. Beaumont C. D. W. Wilkinson 《Solid-state electronics》1989,32(12):1303-1307
We have measured the series resistance of two ballistic resistors, or quantum point contacts, in two configurations. First when the resistors are co-linear we measure the series resistance and the intermediate voltage between the resistors. Using a simple model we calculate the ballistic transport coefficient from the data. We find that the highest values are obtained when one channel is much wider than the other. Poorest transmission is always obtained when the two channels are identical. Secondly, we investigate two quantum point contacts perpendicular to each other. We find that in zero field the resistances and classically but that the transmission coefficient increases if either the magnetic field or the width of the constriction in the ballistic resistors is increased. 相似文献
105.
106.
Moses Azong Cho Jan van Aardt Russell Main Bongani Majeke 《International journal of remote sensing》2013,34(12):3143-3159
Remote sensing is viewed as a cost-effective alternative to intensive field surveys in assessing site factors that affect growth of Eucalyptus grandis over broad areas. The objective of this study was to assess the utility of hyperspectral remote sensing to discriminate between site qualities in E. grandis plantation in KwaZulu-Natal, South Africa. The relationships between physiology-based hyperspectral indicators and site quality, as defined by total available water (TAW), were assessed for E. grandis plantations through one-way analysis of variance (ANOVA). Canopy reflectance spectra for 68 trees (25 good, 25 medium and 18 poor sites) were collected on clear-sky days using an Analytical Spectral Device (ASD) spectroradiometer (350–2500 nm) from a raised platform. Foliar macronutrient concentrations for N, P, K, S, Ca, Mg and Na and their corresponding spectral features were also evaluated. The spectral signals for leaf water – normalized difference water index (NDWI), water band index (WBI) and moisture stress index (MSI) – exhibited significant differences (p < 0.05) between sites. The magnitudes of these indices showed distinct gradients from the poor to the good sites. Similar results were observed for chlorophyll indices. These results show that differences in site quality based on TAW could be detected via imaging spectroscopy of canopy water or chlorophyll content. Among the macronutrients, only K and Ca exhibited significant differences between sites. However, a Tukey post-hoc test showed differences between the good and medium or medium and poor sites, a trend not consistent with the TAW gradient. The study also revealed the capability of continuum-removed spectral features to provide information on the physiological state of vegetation. The normalized band depth index (NBDI), derived from continuum-removed spectra in the region of the red-edge, showed the highest potential to differentiate between sites in this study. The study thus demonstrated the capability of hyperspectral remote sensing of vegetation canopies in identifying the site factors that affect growth of E. grandis in KwaZulu Natal, South Africa. 相似文献
107.
Computational approaches for simulation of light-tissue interactions have provided extensive insight into biophotonic procedures for diagnosis and therapy. However, few studies have addressed simulation of time-resolved fluorescence (TRF) in tissue and none have combined Monte Carlo simulations with standard TRF processing algorithms to elucidate approaches for cancer detection in layered biological tissue. In this study, we investigate how illumination-collection parameters (e.g., collection angle and source-detector separation) influence the ability to measure fluorophore lifetime and tissue layer thickness. Decay curves are simulated with a Monte Carlo TRF light propagation model. Multi-exponential iterative deconvolution is used to determine lifetimes and fractional signal contributions. The ability to detect changes in mucosal thickness is optimized by probes that selectively interrogate regions superficial to the mucosal-submucosal boundary. Optimal accuracy in simultaneous determination of lifetimes in both layers is achieved when each layer contributes 40-60% of the signal. These results indicate that depth-selective approaches to TRF have the potential to enhance disease detection in layered biological tissue and that modeling can play an important role in probe design optimization. 相似文献
108.
Sabrina Colombo M.C. Forde I.G. Main M. Shigeishi 《Construction and Building Materials》2005,19(10):746-754
This paper presents an alternative approach to the problem, based on “testing” the real structure rather than trying to model it. Experiments on reinforced concrete (RC) beams, representative of bridge beams, are described. The beams were loaded in cycles up to failure whilst recording the acoustic emissions (AE) generated. The analysis of the AE signals was then undertaken based on a proposed new parameter, named the “relaxation ratio”. This quantifies the AE energy recorded during the unloading and loading phases of a cycle test and it showed a clear correlation with the bending failure load of the RC beams. A change in trend was noted when the load reached approximately the 45% of the ultimate bending load. The results appeared to be influenced by factors such as the concrete strength and loading rate and further work is needed to extend the results to full scale testing of bridge beams. 相似文献
109.
Automated analyses in MALDI MS are complicated by the uneven distribution of analyte over the sample spot, resulting in areas of analyte localization, or "sweet spots". Hence, the ability to concentrate and localize samples is advantageous, especially for automated studies involving low concentrations of analyte. A method for rapidly creating a removable and affordable hydrophobic surface that is free from memory effect is presented. The potential for such compounds to serve as a practical coating for MALDI targets is examined. An example compound with a complete methodology is shown to increase sample homogeneity, peak intensity, and resolution when used for peptide mixtures with CHCA and DHB. 相似文献
110.
Ping Kwan Johnny Wong Wen Zhang Fabio Bussolotti Xinmao Yin Tun Seng Herng Lei Zhang Yu Li Huang Giovanni Vinai Sridevi Krishnamurthi Danil W. Bukhvalov Yu Jie Zheng Rebekah Chua Alpha T. N'Diaye Simon A. Morton Chao‐Yao Yang Kui‐Hon Ou Yang Piero Torelli Wei Chen Kuan Eng Johnson Goh Jun Ding Minn‐Tsong Lin Geert Brocks Michel P. de Jong Antonio H. Castro Neto Andrew Thye Shen Wee 《Advanced materials (Deerfield Beach, Fla.)》2019,31(23)
Monolayer VSe2, featuring both charge density wave and magnetism phenomena, represents a unique van der Waals magnet in the family of metallic 2D transition‐metal dichalcogenides (2D‐TMDs). Herein, by means of in situ microscopy and spectroscopic techniques, including scanning tunneling microscopy/spectroscopy, synchrotron X‐ray and angle‐resolved photoemission, and X‐ray absorption, direct spectroscopic signatures are established, that identify the metallic 1T‐phase and vanadium 3d1 electronic configuration in monolayer VSe2 grown on graphite by molecular‐beam epitaxy. Element‐specific X‐ray magnetic circular dichroism, complemented with magnetic susceptibility measurements, further reveals monolayer VSe2 as a frustrated magnet, with its spins exhibiting subtle correlations, albeit in the absence of a long‐range magnetic order down to 2 K and up to a 7 T magnetic field. This observation is attributed to the relative stability of the ferromagnetic and antiferromagnetic ground states, arising from its atomic‐scale structural features, such as rotational disorders and edges. The results of this study extend the current understanding of metallic 2D‐TMDs in the search for exotic low‐dimensional quantum phenomena, and stimulate further theoretical and experimental studies on van der Waals monolayer magnets. 相似文献