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41.
The traditional microscope, together with the “routine” hematoxylin and eosin (H & E) stain, remains the “gold standard” for diagnosis of cancer and other diseases; remarkably, it and the majority of associated biological stains are more than 150 years old. Immunohistochemistry has added to the repertoire of “stains” available. Because of the need for specific identification and even measurement of “biomarkers,” immunohistochemistry has increased the demand for consistency of performance and interpretation of staining results. Rapid advances in the capabilities of digital imaging hardware and software now offer a realistic route to improved reproducibility, accuracy and quantification by utilizing whole slide digital images for diagnosis, education and research. There also are potential efficiencies in work flow and the promise of powerful new analytical methods; however, there also are challenges with respect to validation of the quality and fidelity of digital images, including the standard H & E stain, so that diagnostic performance by pathologists is not compromised when they rely on whole slide images instead of traditional stained tissues on glass slides.  相似文献   
42.
Although organizations use a variety of interventions to improve group functioning, getting people to work effectively with each other remains challenging. Because the presence of a dog has been shown to have positive effects on mood and dyadic interaction, we expected that the presence of a companion dog would also have positive effects on people in work groups. One reason for this is that a companion dog is likely to elevate positive emotions, which often promote prosocial behavior. In study 1 (n = 120) and study 2 (n = 120), participants were randomly assigned to either a dogpresent or dog-absent four-person group. Three friendly companion dogs were randomly assigned to the dog-present groups; only one dog at a time was used during any given experimental session. In study 1, groups worked on an interactive problem-solving task; participants in the dog-present group displayed more verbal cohesion, physical intimacy, and cooperation. Study 2 was identical except that participants worked on a decision-making task requiring less interaction; participants in the dog-present condition displayed more verbal cohesion and physical intimacy and gave higher ratings of trustworthiness to fellow group members. In study 3, we examined behavioral indicators of positive emotions in dog-present and dog-absent groups. Naïve observers (n = 160) rated silent, 40-second video clips of interaction in groups where either a dog was (1) present but not visible or (2) not present. Behavior in dog-present groups was rated as more cooperative, comfortable, friendly, active, enthusiastic, and attentive. We discuss areas for future research and implications of our findings for work and educational settings.  相似文献   
43.
Sleep research is characterized by an interest in humans, with the realm of animal sleep left largely to ethologists and animal scientists. However, the lives of sleep-study participants and those with sleep problems frequently involve animals. For the majority of the population in developed countries who own pets, their waking lives are impacted by the duties of animal care and ownership. For many, their sleeping lives are also impacted through sharing their bedrooms or their beds with pets. Yet, little is known about the prevalence of human–animal co-sleeping relationships or their impact on sleep. The aim of this study was to determine the prevalence and implications of human–animal co-sleeping in an Australian sample. The study uses data collected from the 2012 Sealy Sleep Census, a national online survey of sleep wellness that included a sample of 10,128 after data cleaning. The population of respondents (aged 18–74) who co-slept with pets (n = 1,018 or 10% of the sample) was then matched to a sample of respondents who did not co-sleep with pets, according to gender and age. Those who co-slept with pets took longer to fall asleep (p = 0.029), were more likely to wake up tired (p = 0.025), and although they were not more likely to wake up due to a disturbance, those who did had a greater chance of being disturbed by dog barking/animals making noises (p < 0.001). However, there were no significant differences found in total self-reported sleep length or feelings of tiredness during the day. The continued practice of co-sleeping with pets suggests that there may be some benefits such as social support and social interaction, and increased feelings of personal security. The survey provides a preliminary understanding of the prevalence and implications of human–animal co-sleeping, and highlights areas for further examination of its implications on sleep research and clinical practice.  相似文献   
44.
The evolution of maize production patterns in Argentina is evaluated over the last 25 years to compare costs, benefits, environmental performance and sustainability as well as to identify the main driving sources and improvement potential. Results from Argentina cropping systems are compared to other systems worldwide in order to put the Argentina results in a broader context. The study focuses on three farming categories: (1) traditional, low-intensity systems, (2) conventional, high-intensity systems, and (3) GMO-based cropping systems. Low input intensity systems include traditional cropping patterns with seed selection by farmers and conventional hybrid seed coupled to plowing and crop-animal rotation techniques; high input intensity systems use conventional hybrid seeds and recommended chemicals, irrigation and machinery with important soil erosion consequences; and GMO-based cropping systems use herbicide resistant transgenic hybrids, pesticides, higher fertilizer rates, and no-till practices. In each of the three cases, input flows are compared to the achieved yield (in mass and income terms) to better understand relative efficiencies and options for improvement. The study of GMO systems required a preliminary investigation of GMO seed production by seed companies, where a large investment in terms of prior knowledge and high-tech laboratory research is required. The assessments used the Emergy Accounting (EMA) approach. EMA includes material, energy, labor, money, and knowledge flows into the assessment and expands its focus over larger time and spatial scales than conventional economic and cumulative energy demand methods. Emergy-based environmental indicators of grain production for high-intensity hybrid and GMO systems both show a lower performance than low-intensity, traditional patterns in terms of resource return, renewability and sustainability. The fraction of renewability in low-intensity systems is between 28% and 63%, while it is between 8% and 26% for high-intensity hybrid and GMO systems. Calculated indicators also show that GMO-based maize production patterns do not guarantee the expected improvement over conventional high-intensity cropping systems or low-intensity systems in terms of performance and sustainability. Strong reliance on nonrenewable resources and technology, as well as role of direct and indirect labor costs are important factors in determining long-term sustainability and environmental stability of maize production systems.  相似文献   
45.
套作玉米对草莓生长生理特性及其产量和品质的影响   总被引:3,自引:0,他引:3  
该研究采用草莓玉米套作和草莓连作方式,对草莓的生长、生理及其产量和品质进行比较分析,为生产中克服草莓连作障碍提供理论依据。结果表明:(1)套作条件下草莓的株高、根长、茎粗和整株重量等营养生长指标均显著高于相应的连作模式。(2)与连作相比,套作可提高草莓植株的总超氧化物歧化酶(SOD)、乙醇脱氢酶(ADH)和过氧化物酶(POD)活性,同时可提高草莓植株根系和叶片的可溶性糖含量,使根系丙二醛含量维持在较低水平,保证草莓植株良好生长。(3)与草莓连作相比,套作玉米使秋季草莓苗的定植入田死苗率降低28.8%,加快缓苗速度,且单株保持良好长势和后期正常坐果。(4)套作玉米能够显著提高草莓果实的硬度、单果重及单株产量,但对果实可溶性固形物无显著影响。研究认为,草莓套作玉米能够克服草莓连作障碍,促进草莓植株的营养生长,增强草莓植株抵御逆境胁迫的能力,提高产量和品质。  相似文献   
46.
47.
Millions of companion animals are relinquished to shelters each year. For each dog entering, their characteristics and the characteristics of the shelter holding him/her influence their time to adoption. Using a Cox proportional hazards frailty model, these issues were explored using data from 31 shelters within the British Columbia Society for the Prevention of Cruelty to Animals shelter system. Results indicated that surrender reason, age, original source, coat color, breed, human population density of the shelter location, and year the nonhuman animal entered the shelter significantly influenced time to adoption. This study identified characteristics of dogs that make them less likely to be adopted quickly. Given limited resources, these results may help inform shelters on how to best allocate resources, particularly in interventions to improve adoption rates in shelters.  相似文献   
48.
Around the world, human populations have experienced large increases in average lifespan over the last 150 years, and while individuals are living longer, they are spending more years of life with multiple chronic morbidities. Researchers have used numerous laboratory animal models to understand the biological and environmental factors that influence aging, morbidity, and longevity. However, the most commonly studied animal species, laboratory mice and rats, do not experience environmental conditions similar to those to which humans are exposed, nor do we often diagnose them with many of the naturally occurring pathologies seen in humans. Recently, the companion dog has been proposed as a powerful model to better understand the genetic and environmental determinants of morbidity and mortality in humans. However, it is not known to what extent the age‐related dynamics of morbidity, comorbidity, and mortality are shared between humans and dogs. Here, we present the first large‐scale comparison of human and canine patterns of age‐specific morbidity and mortality. We find that many chronic conditions that commonly occur in human populations (obesity, arthritis, hypothyroidism, and diabetes), and which are associated with comorbidities, are also associated with similarly high levels of comorbidity in companion dogs. We also find significant similarities in the effect of age on disease risk in humans and dogs, with neoplastic, congenital, and metabolic causes of death showing similar age trajectories between the two species. Overall, our study suggests that the companion dog may be an ideal translational model to study the many complex facets of human morbidity and mortality.  相似文献   
49.
酚酸物质对黄瓜幼苗及枯萎病菌菌丝生长的影响   总被引:13,自引:0,他引:13  
研究了不同连作年限大棚土壤中酚酸物质的种类、含量及其对黄瓜幼苗和枯萎病菌菌丝生长的影响。结果表明:土壤中香草酸、对羟基苯甲酸及阿魏酸随黄瓜连作年限增加而呈现积累趋势;在连作7年的大棚土壤中3种酚酸类物质总量达29.8mg.kg-1干土,显著高于连作1年和3年土壤中的含量;酚酸物质可使黄瓜幼苗根长及茎粗显著降低,使株高及干物质量略有下降。与对照相比,酚酸物质使黄瓜幼苗体内过氧化物酶(POD)活性在短期内升高,5d后又呈下降趋势;对超氧化物歧化酶(SOD)活性的影响也表现出先升高后下降的变化趋势。高浓度酚酸使黄瓜幼苗丙二醛(MDA)含量持续升高。枯萎病菌菌丝生长测定表明:42h内,低浓度(≤50mg.L-1)酚酸对枯萎病菌丝生长有刺激作用;酚酸浓度高于50mg.L-1时,对菌丝生长有抑制作用;随酚酸处理时间延长,枯萎病菌对酚酸物质的耐受性增强,对高浓度酚酸的生长抑制作用表现不明显。  相似文献   
50.
An understanding of the dynamics of carbon (C) stock in soils, as impacted by management strategies, is necessary to identify the pathways of C sequestration in soils and for maintaining soil organic C (SOC) at a level critical for upkeeping soil health and also for restraining global warming. This is more important in tropical and subtropical region where soils are inherently low in organic C content and the production system is fragile. We evaluated the long‐term role of crop residue C inputs to soil in SOC sequestration and also the critical value of C inputs for maintenance of SOC across five different rice‐based cropping systems and four soil management practices including a fallow (no cultivation since initiation of the experiments) using five long‐term (7–36 years) fertility experiments in subtropical India. Cropping per se always caused a net depletion of SOC. Such depletion was inversely proportional to the amount of crop residue C incorporated into the soils (r=−0.92, P=0.001). Balanced fertilization with NPK, however, caused an enrichment (9.3–51.8% over the control) of SOC, its extent being influenced by the cropping systems. Long‐term application of organic amendments (5–10 Mg ha−1 yr−1) through farmyard manure (FYM) or compost could increase SOC hardly by 10.7% constituting only 18% of the applied C, the rest getting lost through oxidation. The total quantity of soil C sequestered varied from −11.5 to 14.5 Mg C ha−1 and was linearly related (r2=0.40, P=0.005) with cumulative crop residue C inputs to the soils. On an average, the rate of its conversion to SOC came out to be 6.4%. This was more in presence of added organics (6.9%) than in its absence (4.2%). For sustenance of SOC level (zero change due to cropping) we found that a minimum quantity of 2.9 Mg C is required to be added per hectare per annum as inputs. The cropping systems and the management practices that could provide C input higher than the above critical level are likely to sustain the SOC level and maintain good soil health in the subtropical regions of the Indian subcontinent.  相似文献   
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