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11.
Carbon encapsulated iron nanoparticles(CEINPs) with very thin shells and good core-shell structures were prepared by DC arc discharge at argon intake temperature(AIT) of 800 ℃. The results of high resolution transmission electron microscope(HRTEM), energy dispersive X-ray(EDX) spectroscope, X-ray diffraction(XRD), and X-ray photoelectron spectroscope(XPS) characterizations on the product B show that the thickness of the carbon shells of CEINPs in the product B is in the range of ca. 0.5—5.3 nm, i. e., which can be as thin as only two layers of graphite. The average diameter of the CEINPs is about 24. 7 nm. The total content of Fe element in the product B is 77.0 wt%. The saturation magnetization(Ms) and coercivity(Hc) of the product B are 107.4 emu/g and 143 Oe, respectively. The formation of the CEINPs in the product B is discussed briefly. 相似文献
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13.
Rachael Davis Georgina Donati Kier Finnegan James P. Boardman Bethan Dean Sue Fletcher-Watson Gillian S. Forrester 《Child development》2022,93(4):869-880
Visual field biases have been identified as markers of atypical lateralization in children with developmental conditions, but this is the first investigation to consider early lateralized gaze behaviors for social stimuli in preterm infants. Eye-tracking methods with 51 preterm (33 male, 92.1% White) and 61 term-born (31 male, 90.1% White) infants aged 8–10 months from Edinburgh, UK, captured the development of visual field biases, comparing gaze behavior to social and non-social stimuli on the left versus right of the screen. Preterm infants showed a significantly reduced interest to social stimuli on the left versus right compared to term children (d = .58). Preterm children exhibit early differential orienting preferences that may be an early indicator of atypical lateralized function. 相似文献
14.
Christine E. Gould Shruti Shah Sarah R. Brunskill Krista Brown Nancy L. Oliva Charissa Hosseini 《Educational gerontology》2017,43(8):379-392
We describe the development of a telephone-based program, Recreation, Education, and Socialization for Older Learning Veterans (RESOLV) that aims to connect Veterans with one another by phone and thereby reduce loneliness. The program was developed through a collaboration between VA and a community-based organization, Episcopal Senior Communities Senior Center Without Walls (SCWW). Semi-structured interviews were conducted with 18 rural and non-rural dwelling older Veterans to identify leisure interests and potential barriers to participating in leisure activities. Program feasibility was examined with questions about telephone use and interest in and perceived benefits of a telephone community. We conducted content analysis to quantify Veterans’ leisure interests and thematic analysis to characterize barriers to participation. Veterans expressed interest most frequently in groups focused on conversation, support, gratitude, and technology. Rural and non-rural participants did not differ significantly in interests. Barriers to current activity participation included limited access to activities, limitations due to physical conditions, and transportation difficulties, which were consistent themes for both rural and non-rural participants. Themes related to perceived benefits of socialization that emerged include connectedness, learning from others, being active despite limitations, and distraction from limitations. Our findings demonstrate how a telephone-based socialization program could be developed and tailored for older Veterans. It seems that such a program is feasible and may be of benefit for older Veterans in rural and non-rural areas. Further evaluation is needed to ascertain the direct benefit of such a program to older Veterans. 相似文献
15.
The paper explores a collaborative self-study, autoethnography research project, which aided in informing practice for the teaching of reflective practice in Science, Technology, Engineering and Mathematics (STEM) at an Australian university. Self-report methods were used, because it enabled the collection of a variety of self-awareness data generated processes to help produce insights and understandings. This was achieved by undertaking a systematic approach to the exploration of a critical friendship between two academic support staff members alongside reflections from a recorded, focus group interview with nine STEM teachers. Four self-awareness data generated processes were used: (1) self-reflections; (2) collaborative reflections; (3) reflections on pertinent literature findings and (4) reflections from nine STEM teachers. A thematic analysis of the data was undertaken, which resulted in the discovery of three turning points such as moments of understandings that challenge assumptions and/or lead to new insights. The findings indicated that a STEM-centric, scaffolded approach that utilised the scientific method for reflective practice enabled the development of a shared understanding around teaching and assessing reflective practice for STEM teachers. First, because it boosted self-confidence and second, because it reduced scepticism around reflective practice as a non-scientific form of learning. 相似文献
16.
Ajay Kumar D. H. Shah M. G. R. Rajan U. R. Thakare S. M. Sharma 《Indian journal of clinical biochemistry : IJCB》1992,7(2):159-164
An external quality assessment was conducted to assess the performance of various laboratories for RIA of thhyroid related
hormones in two phases. In the first phase thirty five laboratories participated. At the end of first phase a meeting cum
workshop was organised to discuss the results of first phase, difficultires faced by the participants and pinpoint the short
oming. A second phase was then initiated with an objective of improvement in the performance, if any, where twelve samples
from four pools were distributed to twenty four laboratories who participated for the second phase. The overall return of
the results increased significantly from 71.8% (1586/2208) for the first phase to 92.4% (732/792) for the second phase. The
inter laboratory %CV for T3, T4 and TSH were lower during the second phase (30.6%, 19.0% and 31.6% respectively) as compared to those observed during first
phase (36.3%, 22.7% and 52.8% respectively). Similarly, there was an improvement in reproducibility of ALTM as %CV for T3, T4 and TSH decreased from 6.0%, 9.8% and 13.4% respectively to 4.5%, 4.6% and 8.5% respectively. The individual performances
of the participating laboratories viz. bias, variability of bias and imprecision also showed a trend towards improvement as
percent laboratories having desirable or acceptable results for T3, T4 and TSH increased from 10.7%, 60.7% and 0.0% respectively to 20.8%, 66.7% and 22.2% respectively. External quality assessment
thus appears to be beneficial in assessing the performane of a laboratory in comfparison with other laboratories and indeed
helps in improving the performance. 相似文献
17.
Franky D. Shah Rasheedunnisa Begum Bhairavi N. Vajaria Kinjal R. Patel Jayendra B. Patel Shilin N. Shukla Prabhudas S. Patel 《Indian journal of clinical biochemistry : IJCB》2011,26(4):326-334
Oral cancer has emerged as an alarming public health problem with increasing incidence and mortality rates all over the world.
Therefore, the implementation of newer screening and early detection approaches are of utmost importance which could reduce
the morbidity and mortality associated with this disease. Sensitive and specific biomarkers for oral cancer are likely to
be most effective for screening, diagnosis, staging and follow-up for this dreaded malignancy. Unlike other deep cancers,
oral cancer is located in oral cavity. Hence, the direct contact between saliva and oral cancer lesion makes the measurement
of tumor markers in saliva an attractive alternative to serum and tissue testing. The DNA, RNA and protein molecules derived
from the living cancer cells can be conveniently obtained from saliva. Thus, salivary biomarkers, a non-invasive alternative
to serum and tissue-based biomarkers may be an effective modality for early diagnosis, prognostication and monitoring post
therapy status. In the current post-genomic era, various technologies provide opportunities for high-throughput approaches
to genomics and proteomics; which have been used to evaluate altered expressions of gene and protein targets in saliva of
oral cancer patients. The emerging field of salivary biomarkers has great potentials to prove its clinical significance to
combat oral cancer. Hence, we have reviewed importance of several salivary genomics and proteomics biomarkers for oral cancer. 相似文献
18.
Shah C 《Health information and libraries journal》2011,28(1):77-81
This issue's feature column reports on the findings of a small survey of library users carried out in an Indian medical college with a traditional curriculum. The study found that the main reason a student visited the library was to consult text books. Although the majority of students were satisfied with the library facilities, the study suggests that more needs to be done to promote self-directed learning. JM. 相似文献
19.
Controlled electroporation of the plasma membrane in microfluidic devices for single cell analysis 总被引:1,自引:0,他引:1
Chemical cytometry on a single cell level is of interest to various biological fields ranging from cancer to stem cell research. The impact chemical cytometry can exert in these fields depends on the dimensionality of the retrievable analytes content. To this point, the number of different analytes identifiable and additionally their subcellular localization is of interest. To address this, we present an electroporation based approach for selective lysis of only the plasma membrane, which permits analysis of the dissolved cytoplasm, while reducing contributions from the nucleus and membrane bound fractions of the cell analytes. The use of 100 μs long pulse and a well defined DC electric field gradient of ∼4.5 kV·cm−1 generated by 3D electrodes initiates release of a cytoplasm marker in ≪1 s, while retaining nuclear fluorescence markers. 相似文献
20.
Kavita Shalia Sudha Savant Vijaya A. Haldankar Tulip Nandu Poonam Pawar Siddhi Divekar V. K. Shah Purvi Bhatt 《Indian journal of clinical biochemistry : IJCB》2012,27(1):74-82
To analyse the association of high sensitivity C-reactive (hsCRP) protein levels and −717A/G single nucleotide polymorphism
of CRP with acute myocardial infarction (AMI) in the Indian population. Study population included 100 MI cases wherein 32
patients had experienced previous MI (MI-Group-1), 68 MI cases were recruited at presentation (MI-Group-2) and equal number
of age and gender matched healthy individuals. hsCRP levels were determined by ELISA and genotyping of −717A/G was carried
out by polymerase chain reaction-based restriction digestion method. The −717A/G genotypes did not influence hsCRP level and
their distribution did not differ between groups. However, in the present study hsCRP demonstrated significant correlation
with BMI in controls of both the genders and with triglycerides in females of AMI at presentation who otherwise are with low
risk profile. Identifying traditional risk factors associated with inflammation may help in controlling the acute event. 相似文献