Clogging by sieving in microchannels: Application to the detection of contaminants in colloidal suspensions

We report on a microfluidic method that allows measurement of a small concentration of large contaminants in suspensions of solid micrometer-scale particles. To perform the measurement, we flow the colloidal suspension through a series of constrictions, i.e. a microchannel of varying cross-section. We show and quantify the role of large contaminants in the formation of clogs at a constriction and the growth of the resulting filter cake. By measuring the time interval between two clogging events in an array of parallel microchannels, we are able to estimate the concentration of contaminants whose size is selected by the geometry of the microfluidic device. This technique for characterizing colloidal suspensions offers a versatile and rapid tool to explore the role of contaminants on the properties of the suspensions

Successful management of invasive rats across a fragmented landscape

Summary Introduced mammalian predators are responsible for the decline and extinction of many native species, with rats (genus Rattus) being among the most widespread and damaging invaders worldwide. In a naturally fragmented landscape, we demonstrate the multi-year effectiveness of snap traps in the removal of Rattus rattus and Rattus exulans from lava-surrounded forest fragments ranging in size from 10 ha. Relative to other studies, we observed low levels of fragment recolonization. Larger rats were the first to be trapped, with the average size of trapped rats decreasing over time. Rat removal led to distinct shifts in the foraging height and location of mongooses and mice, emphasizing the need to focus control efforts on multiple invasive species at once. Furthermore, because of a specially designed trap casing, we observed low non-target capture rates, suggesting that on Hawai\u27i and similar islands lacking native rodents the risk of killing non-target species in snap traps may be lower than the application of rodenticides, which have the potential to contaminate food webs. These efforts demonstrate that targeted snap-trapping is an effective removal method for invasive rats in fragmented habitats and that, where used, monitoring of recolonization should be included as part of a comprehensive biodiversity management strategy

WHO preferred product characteristics for monoclonal antibodies for passive immunization against respiratory syncytial virus (RSV) disease in infants - Key considerations for global use.

World Health Organization (WHO) preferred product characteristics describe preferences for product attributes that would help optimize value and use to address global public health needs, with a particular focus on low- and middle-income countries. Having previously published preferred product characteristics for both maternal and paediatric respiratory syncytial virus (RSV) vaccines, WHO recently published preferred product characteristics for monoclonal antibodies to prevent severe RSV disease in infants. This article summarizes the key attributes from the preferred product characteristics and discusses key considerations for future access and use of preventive RSV monoclonal antibodies

Assessment of Novel Auditory Rehabilitation Training Methods

Cochlear implants partially restore hearing, but vary greatly in the benefit they provide for their users, making auditory rehabilitation training necessary. This study examined the potential of multiple talkers and top-down processing to enhance the auditory perceptual learning typically seen with normal-hearing participants using cochlear implant simulations. Participants (N = 64) were exposed to one of four lab-based auditory training methods using meaningful sentence materials: control training without cochlear implant simulation, single-talker training, multi- talker training, or training with passages of semantically coherent sentences. In all cases, the experiment involved two pre-tests, one hour of training, and five post-tests to assess perceptual learning and cross-context generalization. Performance above the control was seen in all three experimental groups for sentence recognition in quiet. In addition, the multi-talker training method generalized to a context word recognition task, and the passage training method caused gains in a task involving sentence recognition in multi-talker babble. This indicates that exposure to multiple talkers and semantic cohesion can produce generalized perceptual learning previously unseen with typical single-talker lab training

Filling the void: Grieving and healing during a socially isolating global pandemic

The COVID-19 pandemic has altered life dramatically, including grieving practices. This study examines how people grieved death when they were unable to engage in traditional mourning rituals. Participants shared ways their experiences with grief were affected by the pandemic through themes of (1) physical isolation, including feeling together while apart, and, (2) challenges to grief management, like lack of nonverbal communication and feeling delegitimized. Participants also spoke of memorable messages deemed helpful or hurtful, including (1) emphasizing the death over the loss, (2) community, and (3) faith and advice. The findings yield implications regarding the nature of communal coping, flexibility to grieving practices, and disenfranchised grief during a global pandemic