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Large-Scale Particle Image Velocimetry (LSPIV) has emerged as a reliable technology to measure river surface flow velocity distribution and can be applied to estimate river discharge. Fewer studies have explored the capability of surface turbulence measurements using LSPIV. In this paper, LSPIV is applied to evaluate statistics of surface turbulence of a natural river. Turbulence measurements including velocity fluctuation, velocity spectra and the dissipation rate of turbulent kinetic energy (TKE) are validated by comparing with those measured by an Acoustic Doppler Velocimeter (ADV). Traditionally, estimation of stream discharge through LSPIV needs a secondary measurement to determine river bathymetry and water depth. A new method is presented here to demonstrate that for a fully developed and channel-controlled flow, the cross section geometry can be estimated from the combined measurements of surface mean velocity and the dissipation rate, following the Manning-Strickler formula. Therefore, river discharge can be estimated with LSPIV along with a calibrated Manning's roughness, without additional bathymetry survey. The proposed new method is applied to measure discharge in Milwaukee River (Milwaukee, Wisconsin, U.S.A.), which agreed well with data obtained from a nearby streamgage station. • LSPIV is applied to measure surface turbulence structures in a natural river. • Surface turbulence velocity spectra demonstrated a −5/3 power law. • River depth can be estimated from surface turbulence measured by LSPIV. • River discharge can be measured by LSPIV without channel geometry survey. [ABSTRACT FROM AUTHOR]

This paper offers a theorization of how the state touches. Through an analysis of the extensive 2011 protests over Wisconsin Senate Bill 11, we interrogate the relatively non-violent interactions between police and protesters during the 17-day occupation of the Wisconsin State Capitol building. On display there were diverse police deployments of 'soft' force and haptic touching, technologies that enabled officers to subtly affect the movements and relations of protester crowds without resorting to familiar coercion- and consent-based politics. We offer a pair of concepts, cathexis and l'esprit de l'escalier, to diagram how statist touches were mobilized to catch individuals unawares and momentarily co-opt their bodily affects. These modes of control suggest much greater savvy regarding touch, force, and affect than is often granted in representations of the state apparatus. In light of this, we close with a reflection on the changing tactical grounds for struggle. [ABSTRACT FROM AUTHOR]

There is growing awareness that a substantial share of undergraduates are food insecure, potentially undermining investments in higher education and hindering upward social mobility. This mixed-methods paper uses survey and interview data from low-income students at 42 public colleges and universities in Wisconsin to illuminate the day-to-day experiences of food insecurity and examine how food security status varies across background characteristics. Results indicate that students who grew up in food insecure homes, self-identify as a racial/ethnic minority, live off-campus, and attend college in an urban area are significantly more likely to report the lowest level of food security, often associated with hunger. Students explain that challenges stemming from the interrelationship of lack of time and inadequate money are their biggest barriers to food security. Most rely on friends or family for support, but few students draw on the social safety net, in part due to eligibility restrictions. In recognition of the diversity of students' experiences, we discuss the need for a multi-faceted response to promote food security and student success. [ABSTRACT FROM AUTHOR]