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1.
2.
Automation of the wet sieving process in an instrument for particle size analysis is described. A powder is consecutively subjected to three sieves of any selected meshes from 38 μm up and the resulting fractions are collected individually, including both the undersize and oversize, in a submerged filter. The initial filter weight and the weights of all collected fractions are determined separately and stored in the microcomputer memory. Upon completion of an analysis, the sieved fraction weights are recalled, the total sample weight is calculated, and results are presented as weight per cent. Completion of each sieving step is established by filter weight constancy according to prearranged programming. Upon completion of an analysis, the system backwashes the filter and re-establishes conditions for the next analysis. Tests for accuracy with a standard material and repeated testing for short and long-term reproducibility are included. Applicability to a variety of powders is demonstrated. 相似文献
3.
Lesa Lorenzen Huber Kalpana Shankar Kelly Caine Kay Connelly L. Jean Camp Beth Ann Walker 《International journal of human-computer interaction》2013,29(7):441-455
In-home technologies can support older adults' activities of daily living, provide physical safety and security, and connect elders to family and friends. They facilitate aging in place while reducing caregiver burden. One of older adults' primary concerns about in-home technologies is their potential to reduce human contact, particularly from cherished caregivers. In this exploratory in situ study, we provided an ecosystem of networked monitoring technologies to six older adults and their caregivers. We analyzed the amount and content of communication between them. The amount of noncomputer-mediated communication did not decrease through the 6-week study. The content of communication coalesced into four themes: communication about the technologies, communication facilitated by technologies, intrusiveness of technologies, and fun and playfulness with the technologies. Results suggest that in-home technologies, designed with sensitivity to older adults' primary motivations, have the potential to shape and tailor important relationships in later life. 相似文献
4.
Charles V. Camp Andrew Assadollahi 《Structural and Multidisciplinary Optimization》2013,48(2):411-426
A procedure is developed for the design of reinforced concrete footings subjected to vertical, concentric column loads that satisfies both structural requirements and geotechnical limit states using a hybrid Big Bang-Big Crunch (BB-BC) algorithm. The objectives of the optimization are to minimize cost, CO $_{2}$ emissions, and the weighted aggregate of cost and CO $_{2}$ . Cost is based on the materials and labor required for the construction of reinforced concrete footings and CO $_{2}$ emissions are associated with the extraction and transportation of raw materials; processing, manufacturing, and fabrication of products; and the emissions of equipment involved in the construction process. The cost and CO $_{2}$ objective functions are based on weighted values and are subjected to bending moment, shear force, and reinforcing details specified by the American Concrete Institute (ACI 318-11), as well as soil bearing and displacement limits. Two sets of design examples are presented: low-cost and low-CO $_{2}$ emission designs based solely on geotechnical considerations; and designs that also satisfy the ACI 318-11 code for structural concrete. A multi-objective optimization is applied to cost and CO $_{2}$ emissions. Results are presented that demonstrate the effects of applied load, soil properties, allowable settlement, and concrete strength on designs. 相似文献
5.
6.
Jon J. Camp Cheryl R. Hann Douglas H. Johnson James E. Tarara Richard A. Robb 《Scanning》1997,19(4):258-263
Conventional two-dimensional imaging of the trabecular meshwork (TM) provides limited information about the size, shape, and interconnection of the aqueous channels within the meshwork. Understanding the three-dimensional (3-D) relationships of the channels within this tissue may give insight into its normal function and possible changes present in the eye disease glaucoma. The purpose of our study was to compare laser scanning confocal microscopy with standard 1 μm Araldite-embeddedhistologic sections for 3-D analysis of the trabecular meshwork. In addition, the study was done to determine whether computerized 3-D reconstruction could isolate the fluid spaces of the trabecular meshwork and determine the size of interconnections between the fluid spaces. Confocal microscopy appears comparable to 1 μm Araldite-embedded tissue sections and has the advantage of inherent registration of the serial tissue sections. Three-dimensional reconstruction allowed the isolation of the fluid spaces within the trabecular meshwork and revealed the presence of numerous interconnections between larger fluid spaces. The distribution of these interconnections was randomly arranged, with no predilection for specific regions within the trabecular meshwork. This distribution of constrictions and “expansion chambers” may provide a clue to the mechanism by which subtle histologic changes are associated with increased ocular pressure in glaucoma. 相似文献
7.
Nguyen Nhat Minh Phuong Thien Trung Le Minh Viet Thao Nguyen John Van Camp Katleen Raes 《European Journal of Lipid Science and Technology》2020,122(2)
Rambutan (Nephelium lappaceum L.) peel (RBP) is discarded as the main by‐product during processing of the fruit. Increasing attention is now paid to the valorization of RBP for the recovery of valuable compounds. Geraniin, ellagic acid, quercetin, and rutin are the main phenolic compounds found in methanolic RBP extract. Extracted rambutan peel powder (ERPP) is used to evaluate the oxidative stability of soybean oil stored at 4 and 30 °C in the dark and light and deep fried with potatoes at 160 °C. Tert‐butylhydroquinone (100 µg g?1 oil, TBHQ) serves as positive control. Oil supplemented with ERPP of 1000 µg gallic acid equivalents (GAE) g?1 of oil shows positive effects on the retardation of the oxidation process during storage in comparison with oil without addition. During deep frying, either ERPP (1000 µg GAE g?1) or TBHQ retards the lipid oxidation of oil. Levels of thiobarbituric acid reactive substances of potatoes fried in oil fortified with the extract and TBHQ (0.4–0.59 µg g?1) are much lower than those without the extract (1.31 ± 0.10 µg g?1) (p < 0.05). Therefore, RBP extract exhibits favorable antioxidant effects and can be used for effectively inhibiting lipid oxidation in oil during storage and deep frying. Practical Applications: An extract from rambutan fruit peel containing phenolic compounds, that is, geraniin, ellagic acid, rutin, and quercetin showed promising results to be used as potential antioxidants in soybean oil during deep frying. Both oxidation of the frying oil as well as the oxidation of the food product, that is, potatoes were inhibited. These results demonstrated that rambutan fruit peel extract can be used as a natural antioxidant in frying oil to replace synthetic antioxidants, that is, TBHQ. 相似文献
8.
The intake of fat, saturated and monounsaturated FA (SFA and MUFA), and omega-6 and omega-3 PUFA has been estimated in 641
Belgian women (age 18-39 y). Their food intake was recorded using a 2-d food diary. The PUFA included were linoleic (LA),
alpha-linolenic (LNA), arachidonic (AA), eicosapentaeonoic (EPA), docosapentaenoic (DPA) and docosahexaenoic (DHA) acids.
The mean total fat intake corresponded to 34.3% of total energy intake (E). The mean intake of the FA groups corresponded
to 13.7%, 13.1%, and 6.0% of E, for SFA, MUFA, and PUFA, respectively. The mean intake of LA was 5.3% of E and of LNA was
0.6% of E, with a mean LA/LNA ratio of 8.7. The mean intake of AA was 0.03% of E. The mean intake of EPA, DPA, and DHA was
0.4%, 0.01%, and 0.06% of E, respectively. According to the Belgian recommendations, the total fat and SFA intake was too
high for about three-quarters of the population. The mean LA and overall n-6 PUFA intake corresponded with the recommendation,
with part of the population exceeding the upper level. Conversely, the population showed a large deficit for LNA and n-3 PUFA.
The major food source for LA and LNA was fats and oils, followed by cereal products. The main sources of long-chain PUFA were
fish and seafood, and meat, poultry, and eggs. From a public health perspective, it seems desirable to tackle the problem
of low n-3 PUFA intake. 相似文献
9.
MJ Camp JR Wingard CE Gilmore LS Lin SP Dix TG Davidson RB Geller 《Canadian Metallurgical Quarterly》1998,42(12):3103-3106
This study evaluated the efficacy of low-dose dopamine for prevention of amphotericin B-induced nephrotoxicity in autologous bone marrow transplant and leukemia patients. Seventy-one patients undergoing cytoreductive therapy who required amphotericin B were randomly assigned in an unblinded fashion to a group receiving continuous-infusion low-dose dopamine (3 microgram/kg/min) or a group receiving no dopamine. Amphotericin B was dosed at 0.5 or 1.0 mg/kg/day based on computerized tomography scan results or presence of positive blood cultures. No patient received saline boluses. The rate of nephrotoxicity, severity as graded by Southwest Oncology Group toxicity criteria, and time to each grade of nephrotoxicity were compared between the two groups. Eighty percent of the no-dopamine group and 66.7% of the dopamine group developed nephrotoxicity, defined as a 1.5-fold or greater increase in baseline serum creatinine level (P = 0.20). No statistical difference was noted at any grade of nephrotoxicity between the two groups. Thirty-four percent of patients in the no-dopamine group versus 17.6% in the dopamine group had a 2.5-fold or greater increase in serum creatinine level, which was not statistically significant (P = 0.0888). Ten patients developed grade IV nephrotoxicity and were withdrawn from the study, 7 in the no-dopamine group and 3 in the dopamine group (P = 0.19). The time to each grade of nephrotoxicity was also not significantly different for the two groups. Eleven adverse drug reactions were reported in the dopamine group in comparison to one in the no-dopamine group. Thus, dopamine offers little in the way of prevention of nephrotoxicity associated with amphotericin B therapy. Although the significance of drug reactions in the dopamine group is not clearly established due to lack of cardiac monitoring in the no-dopamine group, dopamine therapy is not without complications. 相似文献
10.
Ultra-high-efficiency strong cation exchange LC/RPLC/MS/MS for high dynamic range characterization of the human plasma proteome 总被引:6,自引:0,他引:6
Shen Y Jacobs JM Camp DG Fang R Moore RJ Smith RD Xiao W Davis RW Tompkins RG 《Analytical chemistry》2004,76(4):1134-1144
High-efficiency nanoscale reversed-phase liquid chromatography (chromatographic peak capacities of approximately 1000: Shen, Y.; Zhao, R.; Berger, S. J.; Anderson, G. A.; Rodriguez, N.; Smith, R. D. Anal. Chem. 2002, 74, 4235. Shen, Y.; Moore, R. J.; Zhao, R.; Blonder, J.; Auberry, D. L.; Masselon, C.; Pasa-Tolic, L.; Hixson, K. K.; Auberry, K. J.; Smith, R. D. Anal. Chem. 2003, 75, 3596.) and strong cation exchange LC was used to obtain ultra-high-efficiency separations (combined chromatographic peak capacities of >10(4)) in conjunction with tandem mass spectrometry (MS/MS) for characterization of the human plasma proteome. Using conservative SEQUEST peptide identification criteria (i.e., without considering chymotryptic or elastic peptides) and peptide LC normalized elution time constraints, the separation quality enabled the identification of proteins over a dynamic range of greater than 8 orders of magnitude in relative abundance using ion trap MS/MS instrumentation. Between 800 and 1682 human proteins were identified, depending on the criteria used for identification, from a total of 365 microg of human plasma. The analyses identified relatively low-level (approximately pg/mL) proteins (e.g., cytokines) coexisting with high-abundance proteins (e.g., mg/mL-level serum albumin). 相似文献