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An ultrasound elasticity microscope was used to map 3-D strain volume in an ex vivo porcine cornea to illustrate its ability to measure the mechanical properties of this tissue. Mechanical properties of the cornea play an important role in its function and, therefore, also in ophthalmic diseases such as kerataconus and corneal ectasia. The ultrasound elasticity microscope combines a tightly focused high-frequency transducer with confocal scanning to produce high-quality speckle over the entire volume of tissue. This system and the analysis were able to generate volume maps of compressional strain in all three directions for porcine corneal tissue, more information than any previous study has reported. Strain volume maps indicated features of the cornea and mechanical behavior as expected. These results constitute a step toward better understanding of corneal mechanics and better treatment of corneal diseases.  相似文献   
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We describe an 80-year-old patient who developed Staphylococcus aureus septicemia several days after the implantation of a double stent in the proximal and mid-left anterior descending artery. The infection was complicated by multiple abscesses in the lungs and liver, as well as by bilateral bacterial endophthalmitis requiring right vitrectomy. Long-term antibiotic treatment was successful. Rarity notwithstanding, heightened awareness of this potential complication of a common cardiac procedure is important since diagnosis and immediate therapy are mandatory.  相似文献   
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Background

Pain management guidelines in the emergency department (ED) may reduce time to analgesia administration (TTA). Intranasal fentanyl (INF) is a safe and effective alternative to intravenous opiates. The effect of an ED pain management guideline providing standing orders for nurse-initiated administration of intranasal fentanyl (INF) is not known. The objective of this study was to determine the impact of a pediatric ED triage-based pain protocol utilizing intranasal fentanyl (INF) on time to analgesia administration (TTA) and patient and parent satisfaction.

Methods

This was a prospective study of patients 3–17?years with an isolated orthopedic injury presenting to a pediatric ED before and after instituting a triage-based pain guideline allowing for administration of INF by triage nurses. Our primary outcome was median TTA and secondary outcomes included the proportion of patients who received INF for pain, had unnecessary IV placement, and patient and parent satisfaction.

Results

We enrolled 132 patients; 72 pre-guideline, 60 post-guideline. Demographics were similar between groups. Median TTA was not different between groups (34.5?min vs. 33?min, p?=?.7). Utilization of INF increased from 41% pre-guideline to 60% post-guideline (p?=?.01) and unnecessary IV placement decreased from 24% to 0% (p?=?.002). Patients and parents preferred the IN route for analgesia administration.

Conclusion

A triage-based pain protocol utilizing INF did not reduce TTA, but did result in increased INF use, decreased unnecessary IV placement, and was preferred by patients and parents to IV medication. INF is a viable analgesia alternative for children with isolated extremity injuries.  相似文献   
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Background

Foodborne disease is a significant problem worldwide. Research exploring sources of outbreaks indicates a pronounced role for food workers'' improper health and hygiene practice.

Objective

To investigate food workers'' perceptions of factors that impact proper food safety practice.

Method

Interviews with food service workers in Baltimore, MD, USA discussing food safety practices and factors that impact implementation in the workplace. A social ecological model organizes multiple levels of influence on health and hygiene behavior.

Results

Issues raised by interviewees include factors across the five levels of the social ecological model, and confirm findings from previous work. Interviews also reveal many factors not highlighted in prior work, including issues with food service policies and procedures, working conditions (e.g., pay and benefits), community resources, and state and federal policies.

Conclusion

Food safety interventions should adopt an ecological orientation that accounts for factors at multiple levels, including workers'' social and structural context, that impact food safety practice.  相似文献   
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Sericin, a protein waste product of the silk industry, was crosslinked with chitosan, and a chitosan–sericin conjugate (CS) was prepared, characterized and used to remove hexavalent chromium (Cr(vi)) ions and methyl orange (MO) dye from aqueous solutions. The CS was shown to effectively remove Cr(vi) ions and MO dye at maximum adsorption capacities (Langmuir) of 139 mg g−1 for Cr(vi) ions and 385 mg g−1 for MO dye. Moreover, the adsorption of both Cr(vi) ions and MO dye was highly pH dependent and varied under different experimental conditions. Cr(vi) ion and MO dye uptake by the CS was confirmed by attenuated total reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy (XPS) and energy dispersive spectrometry analysis. Additionally, XPS analysis of the Cr(vi)-loaded CS revealed that Cr(vi) was reduced to the less toxic Cr(iii). The CS was shown not only to be highly amenable to regeneration, but also to be able to effectively remove MO dye and Cr(vi) ions from a binary mixture.

Sericin, a protein waste product of the silk industry, was crosslinked with chitosan, and a chitosan–sericin conjugate (CS) was prepared, characterized and used to remove hexavalent chromium (Cr(vi)) ions and methyl orange dye from aqueous solutions.  相似文献   
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