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BackgroundThe overall incidence rate of cancer in Nebraska is higher than the national average with cancer being the second leading cause of death in the state. Interventions are required to reduce the cancer burden; however, further research is first needed to identify behavioral cancer risk factors and preventive behaviors among Nebraskans that can be targeted.MethodsA statewide cross-sectional survey of Nebraskans aged 19 and older was conducted in 2019 using an address-based sampling method (n = 1640). Multivariable logistic regression was used to examine factors associated with being up-to-date on cancer screening and with behavioral cancer risk factors and preventive behaviors.Results93.42% of Nebraskans did not meet the daily recommended consumption of fruits and vegetables, and 71.51% did not meet weekly physical activity guidelines. The proportion of adults up to date on cancer screening was 64.57% for breast, 68.83% for cervical, 69.01% for colorectal, and 24.07% for skin cancers. Individuals 65–74 (OR: 3.40, 95% CI: 1.52–7.62) and 75 or older (OR: 3.30, 95% CI: 1.35–8.07) were more likely to be current with their colorectal cancer screening compared to ages 50–64. Hispanics were less likely to be current with mammograms (OR: 0.06, 95% CI: 0.01–0.71) and ever screened for cervical cancer (OR:0.13, 95% CI: 0.02–0.94) compared to Non-Hispanic Whites.ConclusionsDisparities in cancer screening and risk and preventive behaviors exist in Nebraska.ImpactThe study highlights a need for continuing efforts to improve preventive cancer behaviors for the entire population as well as some high-risk populations in Nebraska.  相似文献   
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青少年期是冒险行为的高发期,长期以来研究者对其发生机制进行了大量研究。该文在简要介绍传统决策模型的基础上主要综述了解释青少年冒险行为发生机制的双加工模型,包含模糊痕迹理论、原型-意愿模型两个认知加工模型和双系统模型、成熟不平衡模型两个神经生物学模型。尽管上述模型在一定程度上解释了青春期冒险行为高发的原因,但是这些双加工模型及其有关研究仍存在诸多问题和不足。如关于决策模式存在相互对立的观点、关于认知能力发展存在分歧、模型的适用范围问题、神经生物模型的弊端、缺乏对真实冒险行为的研究等,未来研究对上述方面应予以关注。  相似文献   
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Collective cell migrations drive morphogenesis, wound healing, and cancer dissemination. Cells located at the front are considered leaders while those behind them are defined topologically as followers. Leader cell behaviors, including chemotaxis and their coupling to followers, have been well-studied and reviewed. However, the contributions of follower cells to collective cell migration represent an emerging area of interest. In this perspective, we highlight recent research into the broadening array of follower cell behaviors found in moving collectives. We describe examples of follower cells that possess cryptic leadership potential and followers that lack that potential but contribute in diverse and sometimes surprising ways to collective movement, even steering from behind. We highlight collectives in which all cells both lead and follow, and a few passive passengers. The molecular mechanisms controlling follower cell function and behavior are just emerging and represent an exciting frontier in collective cell migration research.  相似文献   
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In many neuronal systems, information appears to be represented in the activity of populations of neurons. Such neuronal population codes must also be read out, or interpreted, by downstream networks. Recent studies in both vertebrate and invertebrate systems have begun to elucidate some of the general mechanisms underlying these processes. Directed behaviors, that involve a directional response to a directional sensory input, have been a particularly useful context for these studies because, among other things, their input-output relationship is easily defined and experimentally controlled. We have recently shown that the neuronal network underlying a directed behavior in the medicinal leech utilizes a specific population coding scheme based on a neuronal population vector. A population vector of mechanosensory neuron activity correlates well with behavioral output and the connectivity of the downstream network is well suited for accurately reading out this population code. Accepted: 17 April 1999  相似文献   
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Three female and two male captive Humboldt penguins (Spheniscus humboldti) were observed in an enclosed exhibit over a period of 10 months to examine behavioral sex differences and to establish whether captive Humboldt penguins exhibit behavioral activity patterns. There were no statistically significant differences between the behaviors of males and females in six categories: resting, self-maintenance, locomoting, lack of visibility, agonistic behaviors, or pair-directed behaviors. Although not statistically significant, the pair-directed activities of bowing and ecstatic displaying were found to have potential use for sexual identification. Females bowing to males accounted for 77% of the observed bows. Further, males were observed performing 68% of the observed ecstatic displays, while females performed only 32%. Four behavioral phases were defined: molting, proximity, nesting, and “other.” Statistically significant behavioral differences occurred between the four phases for all ethogram behaviors with the exception of agonistic and pair-directed behaviors. Although housed under natural daylight and in an exhibit simulating their habitat in the wild, the captive birds failed to demonstrate a breeding season but bred throughout the study. However, this may have been influenced by one or more of the following factors: a ready supply of food; an air-filtered, temperature-controlled atmosphere; and the presence of an adequate number of nesting sites.  相似文献   
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The monoglyme [CH3OCH2CH2OCH3] and diglyme [CH3O(CH2CH2O)2CH3] adducts of the neodymium tris-hexafluoroacetylacetonato [Nd(hfa)3·monoglyme·H2O and Nd(hfa)3·diglyme] have been synthesised in a single step reaction. They have been characterized by elemental analyzes, mass spectrometry, and IR spectroscopy. Single crystal X-ray diffraction studies provide evidence of a mononuclear nine-coordinated complex with a monocapped square antiprismatic structure for the Nd(hfa)3·diglyme (monoclinic system, space group P21/n; a = 9.7717(2), b = 15.5723(4), c = 20.5620(5) Å, β = 103.668(2)°; Z = 4). The Nd(hfa)3·monoglyme·H2O consists of asymmetric units containing two similar molecules (monoclinic system, space group = C2; a = 16.7057(4), b = 12.2579(4), c = 29.3734(5) Å, β = 101.170(3)°, Z = 8).The mass transport properties of these adducts have been investigated by thermogravimetric analysis which revealed high volatility and good thermal stability with a residue left lower than 3%. The Nd(hfa)3·diglyme has been successfully applied to the low-pressure metal organic chemical vapor deposition (MOCVD) of NdBa2Cu3O7−δ thin films.  相似文献   
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