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1.
In 2013, The Better Image (TBI) was contacted to examine A Play of Selves, a unique work created by artist Cindy Sherman during her graduate studies in 1975. The work is composed of 244 paper doll-like photographs of Sherman that are presented within 72 frames. During initial condition checks, it was noted that a number of individual elements had begun to show signs of chemical staining. Over the course of 2013/2014, a collaborative response was developed with the help of the artist, the artist's printer, the representing gallery, TBI staff and the owner. The main goal was to address the physical and chemical issues present and preserve this work for future exhibition and study. Determining an effective decision- making model based on a hierarchy of values was crucial before undertaking any conservation treatment, as there were several invested parties, each with a different perspective. The focus of this paper is the interplay of our responsibilities as conservators with the concerns of the artist, her gallery, her printer, and the owner to balance aesthetic vs. physical integrity of the artwork, reversibility of treatments, importance of record keeping while developing a balanced response within a world of rapidly disappearing traditional photographic papers.  相似文献   
2.

Introduction

Screening programs for colorectal cancer (CRC) are mainly based on a first-line fecal immunochemical test for hemoglobin (FIT). Fecal M2-type pyruvate kinase (M2-PK) has been evaluated in clinical settings showing promising results for early CRC detection. However, the impact of fecal M2-PK assessment on the performance of first-round CRC screening programs is not known. We investigated whether fecal M2-PK alone or in combination with FIT may improve CRC screening efficacy in the general population.

Materials and methods

A total of 1027 asymptomatic subjects (median age 66 [59-74] years; females 504 [49.1%]), identified through the general practitioners’ rosters, were invited for the collection of 2 fecal samples for FIT and M2-PK evaluation. Participants with at least positive one fecal test were referred for colonoscopy. Quality indicators for screening performance were calculated and analyzed using Fisher’s exact test.

Results

Overall, 572 subjects underwent both FIT and M2-PK assessment (participation rate 55.7%): 93 participants showed positive results for at least one test (positivity rate 16.3%). Only 10 patients were positive for both tests. Attendance rate to colonoscopy was 86.0% and a total of 65 adenomas and 7 cancers were detected. Combined use of FIT and fecal M2-PK permitted the identification of 18 more neoplasm (25%) without improving colonoscopy workload, as deduced by the comparable number needed to scope (P = 0.402).

Conclusion

The addition of M2-PK testing to FIT offers the potential to detect additional neoplasms that either do not bleed or only bleed intermittently without reducing participation rate and without increasing endoscopy workload.Key words: biomarker, colorectal cancer, occult blood, M2-type pyruvate kinase, screening  相似文献   
3.
The need of inspecting a masterpiece of fine art without affecting it led to develop non destructive methods of investigation. In the field of art conservation, several diagnostic techniques are being widely used to inspect works of art, giving different but complementary results. The present work deals with two of these methods, reflectography and thermography, both techniques examining objects in the infrared spectrum but in different wavelength bands. Their integrated data potentially provide a powerful tool for mapping hidden features and alterations of artworks. This was confirmed during the inspections of a 13th century panel painting under restoration at the Opificio delle Pietre Dure laboratories (Florence, Italy). A graphical user interface was also designed to aid operators in the field of conservation dealing with the results of the two IR methods. Many options such as image adjustment, comparison, overlaying and transparency variation, in addition to thermographic elaborations, have been made available to users. Imaging data integration provides a multi-layered and multi-spectral representation of the painting that yields a comprehensive diagnosis confirms the anomalies individuation and reduces the ambiguities of information coming from a single diagnostic method.  相似文献   
4.
This report deals with a program to train the General Practitionners and Pediatricians (P&;P) in child and adolescent mental health (CAMH) counselling, undertaken by the Community Service child neuropsychiatrists (CNs) in the Mugello, a mountain region near Florence (Italy) of approx. 500 square miles, with about 58,000 residents of which 9,000 under eighteen years of age. The program began in 1996 and, after an organizational phase, the P&;P's professional interests and needs dealing with CAMH were tested (review phase). The remarkable P&;P's interest and motivations in CAMH were confirmed by the significant percentage (about 50%) of voluntary attendance and the high percentage (about 91%) of active participation in the meetings and by the 50% increment of first referrals to specialists during a test-period lasting two month (February--March 1997/96). A close-ended questionnaire investigated the most frequent CAMH problems faced by the P&;P, which prevalently turned out to be ordinary events. The high rate (about 54%) of missing responses to questions about the P&;P's possibility to aknowledge their own sources of knowledge on such problems and the high positive response rate (about 70%) indicating a non professional source of knowledge reveal the P&;P's awareness of professional insecurity in CAMH, and this was the cause of their difficulties in distinguishing between ordinary events and psychopathology. The P&;P replied positively in 93% of the cases to the question “do you think it is useful for your professional self-confidence to examine these problem areas in depth?” The method that they preferred proved to be “continuing training courses” (35%). These results provided the basis for the implementation phase with a continuing professional training program. The P&;P's awareness of professional insecurity and the admission of their need for training and information in CAMH motivate their requests for CNs Counselling reference in order to deal with psychiatric cases, while the P&;P's humane approach with patients, revealed during the meetings and in the questionnaire, simplifies the task of training the P&;P to become counsellors in CAMH problems which are less severe.  相似文献   
5.
6.
The adoption of e-Customs platforms to simultaneously ensure regulatory compliance and to facilitate trade is a major strategic issue for governments and customs administrations worldwide. It ensures a more cost-efficient usage of resources while preserving a smooth flow of goods across international borders. Hence, customs administrations are challenged to favor the introduction of IT systems that may enhance the ability to improve information sharing with the business sector, as well as with other governmental agencies. This is often not a straightforward process. As many experts point out, e-Government development projects fail commonly due to the lack of thorough understanding of administration requirements as well as barriers for implementation. Hence, the purpose of this study is to understand what factors enable or hinder the exploitation of e-Customs platforms. By means of a Systematic Literature Review (SLR), a theoretical framework is developed to identify drivers and barriers for usage of e-Government/e-Customs platforms. Thereby, a survey instrument was developed and data was collected in occasion of a World Customs Organization (WCO) Annual Council meeting, which was joined by around 400 customs delegates and officers from 178 WCO member administrations. A total of 94 questionnaires have been collected and analyzed, which gives an approximate response rate of 23% (46% considering only the 178 member administrations). The analysis of data has been performed by a combination of multivariate techniques and ANOVA. Results show that factors like cost-savings and ease of use significantly influence the usage of e-Customs platforms. On the contrary, cost-efficiency and usefulness of e-Customs platforms have no significant impacts. From the perspective of barriers preventing adoption, this paper identifies two main factors: 1) technical constraints and costs and 2) quality and trust. Both these factors significantly influence adoption of information sharing, in the context of business-customs communication.  相似文献   
7.
Energy balance of locomotion with pedal-driven watercraft   总被引:1,自引:0,他引:1  
In this study, we examined the mechanics and energetics of locomotion with a paddle-wheel boat and a water bike. Power output (Wtot) was measured directly on the water bike by means of an instrumented chain-ring. The simultaneous assessment of oxygen uptake (VO2) allowed the computation of the "overall" efficiency of locomotion (etao = Wtot/VO2). Mean etao was 0.27 (s = 0.02), which was unaffected by the speed, and was assumed to be the same for the two boats as both are semi-recumbent bicycles. For the paddle-wheel boat, Wtot was then obtained from etao and measures of VO2. The power to overcome (passive) drag was calculated as Wd = D x v (where D is the force measured by means of a load cell when towing the boats at given speeds). Propelling efficiency was calculated as etap = Wd/Wtot, which was lower with the paddle-wheel boat (mean 0.35, s = 0.01) than with the water bike (mean 0.57, s = 0.01). The observed differences in etap and Wd explain why at the highest speed tested (approximately 3 m s(-1), the energy required to cover a unit distance with the water bike is similar to that required to move the paddle-wheel boat at 1.3 m s-1).  相似文献   
8.
9.

The purpose of this study was to analyse Italian high school and university students’ attitudes towards physics using the Semiotic Cultural Psychological Theory (SCPT). In the SCPT framework, attitudes represent how individuals interpret their experience through the mediation of generalized meaning with which they are identified. A view-of-physics questionnaire was used as an instrument to collect data with 1603 high school and university students. Data were analysed through multiple correspondence analysis and cluster analysis. We identified four generalized meanings of physics: (a) interesting and important for society; (b) a quite interesting, but badly taught subject at school and not completely useful for society; (c) difficult to study and irrelevant for society; and (d) a fascinating and protective niche from society. The identified generalized meanings are significantly correlated to the choice to study physics at undergraduate level and to the choice of attending physics-related activities in high school. Implications for research are discussed.

  相似文献   
10.
The confined flow of red blood cells (RBCs) in microvasculature is essential for oxygen delivery to body tissues and has been extensively investigated in the literature, both in vivo and in vitro. One of the main problems still open in microcirculation is that flow resistance in microcapillaries in vivo is higher than that in vitro. This discrepancy has been attributed to the glycocalyx, a macromolecular layer lining the inner walls of vessels in vivo, but no direct experimental evidence of this hypothesis has been provided so far. Here, we investigate the flow behavior of RBCs in glass microcapillaries coated with a polymer brush (referred to as “hairy” microcapillaries as opposed to “bare” ones with no coating), an experimental model system of the glycocalyx. By high-speed microscopy imaging and image analysis, a velocity reduction of RBCs flowing in hairy microcapillaries as compared to bare ones is indeed found at the same pressure drop. Interestingly, such slowing down is larger than expected from lumen reduction due to the polymer brush and displays an on-off trend with a threshold around 70 nm of polymer brush dry thickness. Above this threshold, the presence of the polymer brush is associated with an increased RBC deformation, and RBC velocity is independent on polymer brush thickness (at the same pressure drop). In conclusion, this work provides direct support to the hypothesis that the glycocalyx is the main factor responsible of the higher flow resistance found in microcapillaries in vivo.  相似文献   
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