This article makes three points. First, the police need public support and cooperation to be effective in their order-maintenance role, and they particularly benefit when they have the voluntary support and cooperation of most members of the public, most of the time. Second, such voluntary support and cooperation is linked to judgments about the legitimacy of the police. A central reason people cooperate with the police is that they view them as legitimate legal authorities, entitled to be obeyed. Third, a key antecedent of public judgments about the legitimacy of the police and of policing activities involves public assessments of the manner in which the police exercise their authority. Such procedural-justice judgments are central to public evaluations of the police and influence such evaluations separately from assessments of police effectiveness in fighting crime. These findings suggest the importance of enhancing public views about the legitimacy of the police and suggest process-based strategies for...

/pdf/enhancing-police-legitimacy-kcud8eorjx.pdf

Enhancing Police Legitimacy

Rising inequality of income and power, along with the recent convulsions in the finance sector, have made the search for alternatives to unbridled capitalism more urgent than ever. Yet there has been a global retreat by the Left: on the assumption that liberal capitalism is the only game in town, political theorists tend to dismiss as utopian any attempt to rethink our social and economic relations. As Fredric Jameson first argued, it is now easier for us to imagine the end of the world than an alternative to capitalism. Erik Olin Wright's "Envisioning Real Utopias" is a comprehensive assault on the quietism of contemporary social theory. Building on a lifetime's work analyzing the class system in the developed world, as well as exploring the problem of the transition to a socialist alternative, Wright has now completed a systematic reconstruction of the core values and feasible goals for Left theorists and political actors. "Envisioning Real Utopias" aims to put the social back into socialism, laying the foundations for a set of concrete, emancipatory alternatives to the capitalist system. Characteristically rigorous and engaging, this will become a landmark of social thought for the twenty-first century.

/pdf/envisioning-real-utopias-5gpnqlnrv6.pdf

Envisioning Real Utopias

A nuclear framework structure termed the nuclear matrix has been isolated and characterized. This matrix forms the major residual structure of isolated nuclei and consists largely of protein with smaller amounts of RNA, DNA, carbohydrate, and phospholipid. The nuclear matrix can be further resolved by combined treatment with DNase and RNase. The remaining nuclear protein structure, after extraction of 90 percent of the nuclear protein, 99.9 percent of the DNA, and 98 percent of the RNA and phospholipid, is termed the nuclear protein matrix. Electron microscopy of this final nuclear protein matrix reveals an interior framework structure composed of residual nucleolar structures associated with a granular and fibrous internal matrix structure. The internal matrix framework is derived from the interchromatinic structures of the nucleus, and is connected to a surrounding residual nuclear envelope layer containing residual nuclear pore complex structures. Sodium dodecyl sulfate-acrylamide gel electrophoresis of the nuclear matrix proteins demonstrates three major polypeptide fractions, P-1, P-2, and P-3, with average molecular weights of approximately 69,000, 66,000 and 62,000, as well as several minor polypeptides which migrate at approximately 50,000 and at higher molecular weights (>100,000). Polypeptides with molecular weights identical to those of P-1, P-2 and P-3 are also components of isolated nuclear envelopes and nucleoli, whereas isolated chromatin contains no detectable matrix polypeptides. This suggests that the major matrix polypeptides are localized in specific structural regions of the nucleus, i.e., nuclear envelope, nucleoli, and interchromatinic structures. The presence of cytochrome oxidase activity in the isolated nuclear matrix indicates that at least some integral proteins of the nuclear membrane are associated with the matrix.

Nuclear matrix: Isolation and characterization of a framework structure from rat liver nuclei

Targeting receptor-mediated endocytotic pathways with nanoparticles: rationale and advances.

This study among 168 couples of dual-earner parents uses insights from previous work-family conflict and crossover research to propose an integrative model delineating how job demands experienced by men and women carry over to the home domain. The authors hypothesized that for both men and women, job demands foster their own work-family conflict (WFC), which in turn contributes to their partners' home demands, family-work conflict (FWC), and exhaustion. In addition, they hypothesized that social undermining mediates the relationship between individuals' WFC and their partners' home demands. The results of structural equation modeling analyses provided strong support for the proposed model. The hypothesis that gender would moderate the model relationships was rejected. These findings integrate previous findings on work-family conflict and crossover theories and suggest fluid boundaries between the work and home domains.

How Job Demands Affect Partners' Experience of Exhaustion : Integrating Work-Family Conflict and Crossover Theory

More than 100 proteins collaborate to build the kinetochore. Using RNAi, Liu et al. (page 41) sort out the responsibilities of key proteins in this process.

The kinetochore is a three-layered disc that sits on either side of the centromere. It links to spindle fibers and helps align and separate mitotic chromosomes. Although researchers have teased out the roles of some kinetochore proteins, they lacked a comprehensive picture of how these molecules interact to assemble the structure.

Liu et al. picked 20 putative kinetochore big shots and knocked them down, one at a time, using RNAi. The team then merged its results with past findings to sketch a map of the connections. Sitting atop the protein hierarchy is CENP-A, which permanently resides on centromeres. At the next level, three branches split off: two are headed by other centromere fixtures, CENP-I and CENP-C, and the third under the direction of the Aurora B kinase, a passenger protein crucial for chromosome separation.

Each branch takes on a different task. CENP-I establishes the three-layered organization, for example. Multiple cross-links tie the branches together, however, so there is no linear chain of command. The researchers are now investigating whether interacting proteins make direct contact or whether other molecules serve as intermediaries. The interaction map might be useful to pharmaceutical researchers developing anticancer drugs that disrupt kinetochore proteins. The map may point the way to biomarkers for monitoring the drugs' effects.

https://rupress.org/jcb/article-pdf/175/1/3a/1326259/2.pdf

Division of labor

![Graphic][1] 

Dividing cells that lack Tektin 2 fail to separate. Like parents sending their child off to college, a dividing cell has to let its offspring go. A microtubule-organizing protein helps ensure that the daughter cell breaks free, 

[Durcan et al.][2] report.

When

https://rupress.org/jcb/article-pdf/181/4/569/1259340/jcb_1814iti.pdf

Cutting the cord

The cellular nuances revealed by electron microscopy (EM) and electron tomography (ET) would have thrilled microscope pioneer Anton van Leeuwenhoek. Today, researchers can see even more details by pairing up these techniques with fluorescence microscopy. Kukulski et al. (1) describe a new procedure that further boosts the sensitivity and precision of this combination of imaging techniques.










FOCAL POINT John Briggs (left), Wanda Kukulski (center), Marko Kaksonen (right), and colleagues (not shown) discovered how to increase the combined sensitivity of electron tomography and fluorescence microscopy. By using fluorescence microscopy to locate a protein that briefly adheres to endocytic sites (top right), the researchers pinpointed an endocytic vesicle (bottom right) as it pinches off from the cell membrane.

PHOTO COURTESY OF SONJA WELSCH



Certain structures and rare or ephemeral events are often difficult to discern with EM and ET. Even if researchers do manage to spot, say, an endocytic vesicle at the very moment it separates from the cell membrane, they need to repeat the feat again and again to collect enough data for statistical analysis. That's why scientists are working to mesh fluorescence microscopy with EM and ET. Although fluorescence microscopy can't match the resolution obtained with EM, it can be an excellent tool for tracking cellular events and differentiating similar structures. Fluorescence microscopy can help researchers narrow down where to look when using EM. “The cell is a big place by EM but a small place for fluorescence microscopy,” says senior author John Briggs.



In the last few years, researchers have developed several procedures to integrate light and electron microscopy. One technique involves observing the sample first with fluorescence microscopy, then immediately freezing and fixing it for EM (2). However, this method cannot image rapidly changing processes, nor can it be used to accurately localize structures within cells. An alternative method entails preparing the specimen first, then using both types of imaging. With this approach, one group has pinpointed individual labeled cells in zebrafish embryos (3), and another team was able to take a close look at intact human mitochondria (4). But the method's precision remains around 0.5 microns, and researchers haven't been able to distinguish anything smaller than an organelle.

“[We can] do EM on a bunch of problems that weren't previously practical.”


Kukulski et al. added a technical twist to increase the resolution of images obtained by correlating light and electron microscopy. They started with the standard steps of freezing the sample, encasing it in resin, and slicing off thin layers that they placed on an EM grid. Before making any observations, the researchers sprinkled the sample with tiny plastic spheres visible with both kinds of microscopy. The particles served as landmarks and enabled the rearchers to precisely match up images from fluorescence microscopy and EM or ET. Kukulski et al. determined that they could often narrow the location of an object to within 100 nm.

The team then put the technique through its paces with three practical tests. The researchers first showed that they could pick out scarce HIV particles lurking among the filopodia protruding from the surface of a cell. Although the virus couldn't infect the dog kidney cells the team studied, the results suggest that the procedure could allow researchers to zero in on HIV particles as they enter human cells.

Another question Kukulski et al. addressed is whether growing microtubules flare at their tips like a pair of bellbottom jeans or adopt a sheet-like shape. Previous studies have supported both possibilities. By tagging microtubules with GFP-labeled mal3p, a protein that adheres to the tips, the team found that most of the tubules showed the flare. Kukulski et al. were also able to capture endocytic vesicles at the moment they break away from the plasma membrane. The protein Rvs167, which latches onto endocytic sites for only about 10 seconds, allowed the researchers to home in on vesicles that were about to separate. They discovered that a vesicle pinches off about halfway through Rvs167’s 10-second attachment period.

The new procedure “allows us to do EM on a bunch of problems that weren't previously practical,” says Briggs. The next step, he adds, is to determine whether other combination techniques are feasible. For example, researchers are working to merge super-resolution microscopy with EM and to integrate cryo-EM with fluorescence microscopy.

https://rupress.org/jcb/article-pdf/192/1/3/1259305/jcb_1921if.pdf

Two microscopes are better than one

It was cell biology's version of the ship in the bottle. How do proteins a cell intends to secrete end up in the endoplasmic reticulum? Winkling out the details of the translocation mechanism that spirits these proteins into the ER required more than 20 years and earned Gunter Blobel of Rockefeller

/pdf/lost-in-translation-the-signal-hypothesis-2swm31skqz.pdf

Lost in translation: the signal hypothesis.

Talk of policy has dominated talk of science for those interested in embryonic stem cell science. But research is continuing, and the advances are making clear why embryonic stem cells are such an important scientific and medical resource.

https://rupress.org/jcb/article-pdf/174/6/743/1325316/743.pdf

Mitch Leslie

Papers

Division of labor

Cutting the cord

Two microscopes are better than one

Lost in translation: the signal hypothesis.

The action behind the words: embryonic stem cell research marches on.