Multidimensional Perfectionism,Depression, and Satisfaction With Life: Differences Among Perfectionists and Tests of a Stress‐Mediation Model

This study examined the relationship between adaptive and maladaptive perfectionism, stress, depression, and satisfaction with life in a sample of undergraduate women. The authors found that maladaptive perfectionists had lower satisfaction with life and higher stress and depression scores compared with adaptive perfectionists. Results also indicated that stress mediated the relationship between maladaptive perfectionism and depression and between both maladaptive and adaptive perfectionism and satisfaction with life. Implications for college counselors are discussed.     

Thinking back: becoming aware of the global and its impact on choice

Teaching decisions made ‘in the moment’ do not often allow for deliberate, well thought through actions by teachers. Sometimes we are conscious of the options that are available and we do make deliberate decisions. We may even be aware of the values impinging on our decision, but for many other aspects embedded in our teaching, deeper influences impact. They may never become conscious. Sometimes though, over time and with reflection, we do uncover the influences to which we are beholden. In this paper, I reflect on moments that for me were local, but in which were embedded the influences of the global although I was not always aware of this at the time. Through these moments, I comment and attempt to nuance ideas espoused by the authors in this issue.     

Recreating blood-brain barrier physiology and structure on chip: A novel neurovascular microfluidic bioreactor

The blood-brain barrier (BBB) is a critical structure that serves as the gatekeeper between the central nervous system and the rest of the body. It is the responsibility of the BBB to facilitate the entry of required nutrients into the brain and to exclude potentially harmful compounds; however, this complex structure has remained difficult to model faithfully in vitro. Accurate in vitro models are necessary for understanding how the BBB forms and functions, as well as for evaluating drug and toxin penetration across the barrier. Many previous models have failed to support all the cell types involved in the BBB formation and/or lacked the flow-created shear forces needed for mature tight junction formation. To address these issues and to help establish a more faithful in vitro model of the BBB, we have designed and fabricated a microfluidic device that is comprised of both a vascular chamber and a brain chamber separated by a porous membrane. This design allows for cell-to-cell communication between endothelial cells, astrocytes, and pericytes and independent perfusion of both compartments separated by the membrane. This NeuroVascular Unit (NVU) represents approximately one-millionth of the human brain, and hence, has sufficient cell mass to support a breadth of analytical measurements. The NVU has been validated with both fluorescein isothiocyanate (FITC)-dextran diffusion and transendothelial electrical resistance. The NVU has enabled in vitro modeling of the BBB using all human cell types and sampling effluent from both sides of the barrier.     

Cascaded spiral microfluidic device for deterministic and high purity continuous separation of circulating tumor cells

Inertial microfluidics is an emerging class of technologies developed to separate circulating tumor cells (CTCs). However, defining design parameters and flow conditions for optimal operation remains nondeterministic due to incomplete understanding of the mechanics, which has led to challenges in designing efficient systems. Here, we perform a parametric study of the inertial focusing effects observed in low aspect ratio curvilinear microchannels and utilize the results to demonstrate the isolation of CTCs with high purity. First, we systematically vary parameters including the channel height, width, and radius of curvature over a wide range of flow velocities to analyze its effect on size dependent differential focusing and migration behaviors of binary (10 μm and 20 μm) particles. Second, we use these results to identify optimal flow regimes to achieve maximum separation in various channel configurations and establish design guidelines to readily provide information for developing spiral channels tailored to potentially arbitrary flow conditions that yield a desired equilibrium position for optimal size based CTC separation. Finally, we describe a fully integrated, sheath-less cascaded spiral microfluidic device to continuously isolate CTCs. Human breast cancer epithelial cells were successfully extracted from leukocytes, achieving 86.76% recovery, 97.91% depletion rate, and sustaining high viability upon collection to demonstrate the versatility of the device. Importantly, this device was designed without the cumbersome trail-and-error optimization process that has hindered the development of designing such inertial microfluidic systems.     

大学排行榜之困

大学排行榜在全球各地风靡一时,在21世纪充满竞争、面向市场的学术界,大学排名势所难免,但因评选方法存在诸多缺陷以及排行榜自身的原因,大学排名活动已招致多方批评。排行榜存在的问题跟实践有关,而与原则无关,要解决这些问题,首先应确立公众普遍认可的排名原则,而为这些原则提供合适的衡量办法也必不可少。