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1.
Managing perishability may represent a remarkable problem in supply chain management of a varied set of industries. In fact, perishability can influence, for example, productivity or customer service and it may happen to occur in one or more processes throughout the supply chain. In this paper a review on planning models that handle perishability issues in production and distribution is conducted. The contribution of this paper is three-fold. First, a new framework for classifying perishability models based on multiple process features is presented. Second, it draws the community attention to the importance of managing perishability in many different industries’ supply chains by showing its relevance and by reviewing the literature related to production and distribution planning. Finally, it points towards research opportunities so far not addressed by the research community in this challenging field.  相似文献   

2.
This review of microsurgery considers the current status of both experimental and clinical uses of microsurgery in the fields of otolaryngology, ophthalmology, gynecology, the central and peripheral nervous systems, the vascular system and transplantation. A report of studies on the microcirculation of blood vessels and nerves demonstrated the usefulness of mignification for research studies and emphasized certain factors which could be significant in selecting the best techniques for repairing nerves and blood vessels. Techniques of repair are included, for they have been changed on the basis of experimental studies. Consideration has been given to the advantages of magnification in identification and removal of tumors and vascular anomalies. A report on the use of microtechniques for repairing fallopian tubes is included. It provides a basis for reviewing the problems associated with the repair of small tubes and ducts. The need for microtechniques should increase as medical progress calls for greater precision for the fields of reparative, reimplantation and transplantation surgery.  相似文献   

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Purpose

To reduce the environmental impact of the building sector, environmental targets considering the full life cycle of buildings can be supportive. In recent years, various benchmarks based on Life Cycle Assessment (LCA) have been developed as part of regulations, labelling systems, sustainability rating tools and research studies. The objective of this paper is to critically analyse 23 existing benchmarking systems focusing on the benchmark methodology but also on the benchmark applications and communication.

Methods

The critical literature review consists of two parts. In a first part, the choices related to the assessment method, functional equivalent, definition of benchmark values, benchmark scope, benchmark applications and benchmark communication are compared. In the second part, benchmark values are compiled from literature and statistically analysed.

Results and discussion

The comparative analysis allows to identify the main approaches and methods used in benchmarking systems. For each evaluation aspect, the strengths and weaknesses of the various approaches are highlighted. The statistical analysis provides insight in the spread of benchmark values. Important variations are found between the literature sources which can be explained by differences in benchmark approach, scope, system boundaries and applications.

Conclusions

Based on the comparative analysis, recommendations are formulated for the development of LCA benchmarks for the building sector. The results of the statistical analysis furthermore provide reference values which can be used for the validation of future benchmarks. For global warming, the statistical values for the full life cycle impacts (i.e. embodied and operational impacts) range from about 15 up to 35 kg CO2 eq/m2.a.

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5.
Pinnipeds rely primarily on oxygen stores in blood and muscles to support aerobic diving; therefore rapid development of body oxygen stores (TBO2) is crucial for pups to transition from nursing to independent foraging. Here, we investigate TBO2 development in 45 harp (Pagophilus groenlandicus) and 46 hooded (Cystophora cristata) seals ranging in age from neonates to adult females. We found that hooded seal adults have the largest TBO2 stores yet reported (89.5 ml kg−1), while harp seal adults have values more similar to other phocids (71.6 ml kg−1). In adults, large TBO2 stores resulted from large blood volume (harp169, hood 194 ml kg−1) and high muscle Mb content (harp 86.0, hood 94.8 mg g−1). In contrast, pups of both species had significantly lower mass-specific TBO2 stores than adults, and stores declined rather than increased during the nursing period. This decline was due to a reduction in mass-specific blood volume and the absence of an increase in the low Mb levels (harp 21.0, hood 31.5 mg g−1). Comparisons with other phocid species suggests that the pattern of blood and muscle development in the pre- and post-natal periods varies with terrestrial period, and that muscle maturation rates may influence the length of the postweaning fast. However, final maturation of TBO2 stores does not take place until after foraging begins.  相似文献   

6.
Certain types of food, such as catering foods, decay very rapidly. This paper investigates how the quality of such foods can be improved by shortening the time interval between production and delivery. To this end, we develop an approach that integrates short-term production and distribution planning in an iterative scheme. Further, an aggregation scheme is developed as the interface between the production scheduling and distribution problem. The production scheduling problem is solved through an MILP modeling approach which is based on a block planning formulation. Our implementation shows promising results, elaborated in a numerical investigation, which recollects the real settings of a catering company located in Denmark.  相似文献   

7.
The prevalence of viable Toxoplasma gondii was determined in 6,282 samples (2,094 each of beef, chicken, and pork) obtained from 698 retail meat stores from 28 major geographic areas of the United States. Each sample consisted of a minimum of 1 kg of meat purchased from the retail meat case. To detect viable T. gondii, meat samples were fed to T. gondii-free cats and feces of cats were examined for oocyst shedding. Initially, 100 g of meat from 6 individual samples of a given species were pooled (total, 600 g), fed to a cat over a period of 3 days, and feces were examined for oocysts for 14 days; the remaining meat samples were stored at 4 C for 14 days (until results of the initial cat fecal examination were known). When a cat fed pooled samples had shed oocysts, 6 individual meat samples from each pool were bioassayed for T. gondii in cats and mice. Toxoplasma gondii isolates were then genetically characterized using the SAG2 locus and 5 hypervariable microsatellite loci. In all, 7 cats fed pooled pork samples shed oocysts. Toxoplasma gondii oocysts were detected microscopically in the feces of 2 of the cats; 1 isolate was Type II and the second was Type III. Analyzed individually, T. gondii was detected by bioassay in 3 of the 12 associated samples with genetic data indicating T. gondii isolates present in 2. The remaining 5 pooled pork samples had so few oocysts that they were not initially detected by microscopic examination, but rather by mouse bioassay of cat feces. Two were Type I, 1 was Type II, and 2 were Type III. None of the cats fed chicken or beef samples shed oocysts. Overall, the prevalence of viable T. gondii in retail meat was very low. Nevertheless, consumers, especially pregnant women, should be aware that they can acquire T. gondii infection from ingestion of undercooked meat, and in particular, pork. Cooking meat to an internal temperature of 66 C kills T. gondii.  相似文献   

8.
Cold urticaria is one of the five most common causes of chronic urticaria and is grouped as a physical urticaria. It can occur after exposure to cold, either through solid objects, air or liquids. Patients may have symptoms of urticaria, angioedema, respiratory distress and even anaphylaxis when the skin is exposed to a cold environment, such as handling refrigerated objects, swimming in cold water or entering an air-conditioned room. Five cases of cold urticaria are presented, followed by a brief literature review.  相似文献   

9.
Bryophytes and heavy metals: a literature review   总被引:14,自引:0,他引:14  
The literature on heavy metals in bryophytes is reviewed, including mechanisms of metal uptake, retention, toxicity and tolerance. Interspecies differences in particular are discussed, including the development of extreme tolerance encountered in certain taxa. The use of bryophytes in monitoring heavy metal deposition is considered and comparisons are made with direct deposition measurements.  相似文献   

10.
Research into a connection between religiosity and health was neglected in scientific circles until recently. However, the interest in interactions between religiosity and mental and physical health has started to grow lately. A large proportion of published empirical data suggest that religious commitment shows positive associations with better mental and physical health outcomes. There are relatively few studies showing no effect or negative effect of religiosity on health outcomes. Despite somewhat inconclusive empirical evidence, because of the difficulties encountered in studying the topic, this area is worth of further investigation. The article reviews the literature on epidemiological and clinical studies regarding the relationship between religiosity and mental and physical health. The mentioned issues are discussed and directions for future research are proposed.  相似文献   

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13.
Microsporum gypseum is a geophilic fungus infrequent agent of human dermatophytoses and world-wide in distribution. In Cadiz, Spain, between 1997 and 2003, a study of 133 positive cases showed that the fifth more isolated dermatophyte was M. gypseum (6.0%), followed by Trichophyton mentagrophytes (24,8%), Microsporun canis (24,6%), Trichophyton rubrum (21,8%) y Trichophyton violaceum (6,8%). During 2003 the infection due to this fungus has been repeatedly observed in our area (17.5%). We report herein eight new cases of infection by M. gypseum. Our epidemiological data were compared with those obtained by other authors in other regions of Spain and in those reported in other countries.  相似文献   

14.
Z Zhao  S Li  G Liu  F Yan  X Ma  Z Huang  H Tian 《PloS one》2012,7(7):e41641

Background and Objective

Emerging evidence from biological and epidemiological studies has suggested that body iron stores and heme-iron intake may be related to the risk of type 2 diabetes (T2D). We aimed to examine the association of body iron stores and heme-iron intake with T2D risk by conducting a systematic review and meta-analysis of previously published studies.

Research Design and Methods

Systematic review and subsequent meta-analysis were conducted by searching MEDLINE database up to June 22, 2012 to identify studies that analyzed the association of body iron stores or dietary heme-iron intake with T2D risk. The meta-analysis was performed using the effect estimates and 95% confidence intervals (CIs) to calculate the pooled risk estimates, while the heterogeneity among studies was examined using the I2 and Q statistic.

Results

The meta-analysis included 16 high-quality studies: 12 studies analyzed ferritin levels (4,366 T2D patients and 41,091 controls) and 4 measured heme-iron intake (9,246 T2D patients and 179,689 controls). The combined relative risk (RR) comparing the highest and lowest category of ferritin levels was 1.66 (95% CI: 1.15–2.39) for prospective studies, 2.29 (95% CI: 1.48–3.54) for cross-sectional studies with heterogeneity (Q = 14.84, p = 0.01, I2 = 66.3%; Q = 44.16, p<0.001, I2 = 88.7%). The combined RR comparing the highest and lowest category of heme-iron intake was 1.31 (95% CI: 1.21–1.43) with heterogeneity (Q = 1.39, p = 0.71, I2 = 0%). No publication bias was found. Additional 15 studies that were of good quality, had significant results, and analyzed the association between body iron stores and T2D risk were qualitatively included in the systematic review.

Conclusions

The meta-analysis and systematic review suggest that increased ferritin levels and heme-iron intake are both associated with higher risk of T2D.  相似文献   

15.
Human toxocariasis (HT) is a zoonotic disease caused by infection with the larval stage of Toxocara canis, the intestinal roundworm of dogs. Infection can be associated with a wide clinical spectrum varying from asymptomatic to severe organ injury. While the incidence of symptomatic human toxocariasis appears to be low, infection of the human population is widespread. In Cuba, a clear overview on the status of the disease is lacking. Here, we review the available information on toxocariasis in Cuba as a first step to estimate the importance of the disease in the country. Findings are discussed and put in a broader perspective. Data gaps are identified and suggestions on how to address these are presented. The available country data suggest that Toxocara infection of the definitive dog host and environmental contamination with Toxocara spp. eggs is substantial, but information on HT is less conclusive. The availability of adequate diagnostic tools in the country should be guaranteed. Dedicated studies are needed for a reliable assessment of the impact of toxocariasis in Cuba and the design of prevention or control strategies.  相似文献   

16.
Temozolomide (TMZ) is an alkylating, antineoplastic agent which is being used to treat cases of refractory anaplastic astrocytoma, newly-diagnosed glioblastoma multiforme and metastatic melanoma. TMZ causes lymphopenia and T-cell dysfunction in most of the patients. Related to this toxicity several opportunistic infections have been reported in the literature, but were not well characterized. To further investigate this topic, relevant English language studies were identified through Medline. There were 36 previously reported cases of infection related to TMZ. The median age of the cases was 55 years (range 33-73). The most frequently experienced infections were mucocutaneous candidiasis (n=11; 28.2%), herpes zoster (n=5; 12.8%), herpes simplex virus (n=4; 10.2%), cytomegalovirus (CMV) (n=5; 12.8%), pneumocystis carinii pneumonia (PCP) (n=3; 7.6%), hepatitis B virus (HBV) (n=2; 5.1%) and others (n=9; 23%). Mortality rates were 28.5% (n=4/14) in patients with reported outcome. In this survey, about one third of the TMZ-related severe infections resulted in death. Patients treated with TMZ are at increased risk for opportunistic viral and bacterial infection. Therefore, close monitoring of patients receiving TMZ for opportunistic infections should be carried out.  相似文献   

17.
We report an exceptional case of a very late local failure in a 9-year-old boy presenting with a chordoma of the cranio-cervical junction. The child was initially treated with a combination of surgical resection followed by high dose photon–proton radiation therapy. This aggressive therapy allowed a 9-year remission with minimal side-effects. Unfortunately, he subsequently presented with a local failure managed with a second full-dose course of protons. The child died one year later from local bleeding of unclear etiology.Keyword: Chordoma, Sarcoma, Protontherapy, Children  相似文献   

18.
With the rapid advances of various high-throughput technologies, generation of '-omics' data is commonplace in almost every biomedical field. Effective data management and analytical approaches are essential to fully decipher the biological knowledge contained in the tremendous amount of experimental data. Meta-analysis, a set of statistical tools for combining multiple studies of a related hypothesis, has become popular in genomic research. Here, we perform a systematic search from PubMed and manual collection to obtain 620 genomic meta-analysis papers, of which 333 microarray meta-analysis papers are summarized as the basis of this paper and the other 249 GWAS meta-analysis papers are discussed in the next companion paper. The review in the present paper focuses on various biological purposes of microarray meta-analysis, databases and software and related statistical procedures. Statistical considerations of such an analysis are further scrutinized and illustrated by a case study. Finally, several open questions are listed and discussed.  相似文献   

19.
An 18-year-old girl had a cyst excised from the left buttock in 1988. The cyst was diagnosed to be a cutaneous ciliated cyst, since histologic examination using special stains demonstrated its lining to be similar to fallopian tube epithelium. Only 20 such cases have been published to date, and this report is probably the first case in the plastic surgical literature, to the best of our knowledge.  相似文献   

20.
Over the last decade, genome-wide association studies (GWAS) have become the standard tool for gene discovery in human disease research. While debate continues about how to get the most out of these studies and on occasion about how much value these studies really provide, it is clear that many of the strongest results have come from large-scale mega-consortia and/or meta-analyses that combine data from up to dozens of studies and tens of thousands of subjects. While such analyses are becoming more and more common, statistical methods have lagged somewhat behind. There are good meta-analysis methods available, but even when they are carefully and optimally applied there remain some unresolved statistical issues. This article systematically reviews the GWAS meta-analysis literature, highlighting methodology and software options and reviewing methods that have been used in real studies. We illustrate differences among methods using a case study. We also discuss some of the unresolved issues and potential future directions.  相似文献   

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