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The cellular recycling process of autophagy has been extensively characterized with standard assays in yeast and
mammalian cell lines. In multicellular organisms, numerous external and internal factors differentially affect autophagy
activity in specific cell types throughout the stages of organismal ontogeny, adding complexity to the analysis of
autophagy in these metazoans. Here we summarize currently available assays for monitoring the autophagic process in the nematode C. elegans. A combination of measuring levels of the lipidated Atg8 ortholog LGG-1, degradation of well characterized autophagic substrates such as germline P granule components and the SQSTM1/p62 ortholog SQST-1,
expression of autophagic genes and electron microscopy analysis of autophagic structures are presently the most
informative, yet steady-state, approaches available to assess autophagy levels in C. elegans. We also review how altered autophagy activity affects a variety of biological processes in C. elegans such as L1 survival under starvation conditions, dauer formation, aging, and cell death, as well as neuronal cell specification. Taken together, C. elegans is emerging as a powerful model organism to monitor autophagy while evaluating important physiological roles for autophagy in key developmental events as well as during adulthood.

In the last decade, C. elegans has emerged as an invertebrate organism to study interactions between hosts and pathogens, including the host defense against gram-negative bacterium Salmonella typhimurium. Salmonella establishes persistent infection in the intestine of C. elegans and results in early death of infected animals. A number of immunity mechanisms have been identified in C. elegans to defend against Salmonella infections. Autophagy, an evolutionarily conserved lysosomal degradation pathway, has been shown to limit the Salmonella replication in C.
elegans and in mammals. Here, a protocol is described to infect C. elegans with Salmonella typhimurium, in which the worms are exposed to Salmonella for a limited time, similar to Salmonella infection in humans. Salmonella infection significantly shortens the lifespan of C. elegans. Using the essential autophagy gene bec-1 as an example, we combined this infection method with C. elegans RNAi feeding approach and showed this protocol can be used to examine the function of C. elegans host genes in defense against Salmonella infection. Since C. elegans whole genome RNAi libraries are available, this protocol makes it possible to comprehensively screen for C. elegans genes that protect against
Salmonella and other intestinal pathogens using genome-wide RNAi libraries.

Salmonella typhimurium infects both intestinal epithelial cells and macrophages. Autophagy is a lysosomal
degradation pathway that is present in all eukaryotes. Autophagy has been reported to limit the
Salmonella replication in Caenorhabditis elegans and in mammals. However, it is unknown whether intestinal
autophagy activity plays a role in host defense against Salmonella infection in C. elegans. In this
study, we inhibited the autophagy gene bec-1 in different C. elegans tissues and examined the survival
of these animals following Salmonella infection. Here we show that inhibition of the bec-1 gene in the
intestine but not in other tissues confers susceptibility to Salmonella infection, which is consistent with
recent studies in mice showing that autophagy is involved in clearance of Salmonella in the intestinal epithelial
cells. Therefore, the intestinal autophagy activity is essential for host defense against Salmonella
infection from C. elegans to mice, perhaps also in humans.

Spinster (Spin) in Drosophila or Spinster homolog 1 (Spns1) in vertebrates is a putative lysosomal H+-carbohydrate
transporter, which functions at a late stage of autophagy. The Spin/Spns1 defect induces aberrant autolysosome formation that leads to embryonic senescence and accelerated aging symptoms, but little is known about the mechanisms leading to the pathogenesis in vivo. Beclin 1 and p53 are two pivotal tumor suppressors that are critically involved in the autophagic process and its regulation. Using zebrafish as a genetic model, we show that Beclin 1 suppression ameliorates Spns1 lossmediated senescence as well as autophagic impairment, whereas unexpectedly p53 deficit exacerbates both of these characteristics. We demonstrate that ‘basal p53’ activity plays a certain protective role(s) against the Spns1 defect-induced senescence via suppressing autophagy, lysosomal biogenesis, and subsequent autolysosomal formation and maturation, and that p53 loss can counteract the effect of Beclin 1 suppression to rescue the Spns1 defect. By contrast, in response to DNA damage, ‘activated p53’ showed an apparent enhancement of the Spns1-deficient phenotype, by inducing both autophagy and apoptosis. Moreover, we found that a chemical and genetic blockage of lysosomal acidification and biogenesis mediated by the vacuolar-type H+-ATPase, as well as of subsequent autophagosome-lysosome fusion, prevents the appearance of the hallmarks caused by the Spns1 deficiency, irrespective of the basal p53 state. Thus, these results provide evidence that Spns1 operates during autophagy and senescence differentially with Beclin 1 and p53.

Modulation of neuronal circuits is key to information
processing in the brain. The majority of neuromodulators
exert their effects by activating G-proteincoupled
receptors (GPCRs) that control the production
of second messengers directly impacting
cellular physiology. How numerous GPCRs integrate
neuromodulatory inputs while accommodating diversity
of incoming signals is poorly understood. In
this study, we develop an in vivo tool and analytical
suite for analyzing GPCR responses by monitoring
the dynamics of a key second messenger, cyclic
AMP (cAMP), with excellent quantitative and spatiotemporal
resolution in various neurons. Using this imaging
approach in combination with CRISPR/Cas9
editing and optogenetics, we interrogate neuromodulatory
mechanisms of defined populations of
neurons in an intact mesolimbic reward circuit and
describe how individual inputs generate discrete
second-messenger signatures in a cell- and receptor-
specific fashion. This offers a resource for studying
native neuronal GPCR signaling in real time.

Interprofessional education (IPE) and healthcare collaboration expectations have been established in both educational
and clinical settings nationally and internationally. While multiple models for implementation have been developed,
identifying the best model can be challenging. Through presenting a review of considerations pertinent to structuring
nursing education in the context of IPE, as well as to provide a brief overview of IPE models and exemplars of programs
using IPE, this article identifies gaps in, and the lack of, analysis and evaluation of IPE and its effectiveness on quality
outcomes. In addition, benefits and barriers to IPE and IPCP will be discussed. Recommendations to nursing programs
for IPE inclusion in curricula will be addressed.

Firm managers make ethical decisions regarding the form and quality of disclosure. Disclosure can have long-term implications for performance, earnings manipulation, and even fraud. We investigate the impact of venture capital (VC) backing on the quality and informativeness of disclosure controls and procedures for newly public companies. We find that these controls and procedures are stronger, as evidenced by fewer material weaknesses in internal control under Section 302 of the Sarbanes–Oxley Act, when companies are VC-backed. Moreover, these disclosures are informative and are more likely to be followed by subsequent financial statement restatements than are disclosures made by non-VC-backed IPO companies.

Fraud in the reward-based crowdfunding market has been of concern to regulators, but it is arguably of greater importance to the nascent industry itself. Despite its significance for entrepreneurial finance, our knowledge of the occurrence, determinants, and consequences of fraud in this market, as well as the implications for the business ethics literature, remain limited. In this study, we conduct an exhaustive search of all media reports on Kickstarter campaign fraud allegations from 2010 through 2015. We then follow up until 2018 to assess the ultimate outcome of each allegedly fraudulent campaign. First, we construct a sample of 193 fraud cases, and categorize them into detected vs. suspected fraud, based on a set of well-defined criteria. Next, using multiple matched samples of non-fraudulent campaigns, we determine which features are associated with a higher probability of fraudulent behavior. Second, we document the short-term negative consequences of possible breaches of trust in the market, using a sample of more than 270,000 crowdfunding campaigns from 2010 through 2018 on Kickstarter. Our results show that crowdfunding projects launched around the public announcement of a late and significant misconduct detection (resulting in suspension) tend to have a lower probability of success, raise less funds, and attract fewer backers.

Service-learning and undergraduate research experiences are high-impact practices that have become
more common in the sciences, but the benefits of short-term experiences have not been thoroughly investigated.
The purpose of this study was to compare within-semester gains for students in a short-term service-
learning (SL) or short-term research project (RP) in terms of students’ (i) motivation to learn biology,
(ii) scientific literacy, (iii) perception of the relevance of biology to their lives, and (iv) learning gains associated
with course learning outcomes. The impacts of brief service-learning and research project experiences
were compared using direct and indirect assessments, including qualitative coding of open-ended
response questions and quantitative analysis of exams and Likert-type items. We found few differences
between students in the two projects regarding their changes in motivation (both slightly negative), scientific
literacy (both gains), and their ability to connect biology to their lives (both gains). Emergent themes
revealed that both projects influenced students’ plans for future research and service-learning. Both projects
helped students build relationships; however, RP students built relationships with classmates, while SL
students built relationships with community members. The positive experiences highlight the need for
engaging science students through service-learning in addition to research.

Abundance of the prymnesiophyte Phaeocystis
pouchetii was quantified via light microscopy at 2-week to
monthly intervals in Massachusetts Bay (southern Gulf of
Maine, NW Atlantic) during 1992–2012. Variability in the
abundance and seasonal cycle of Phaeocystis are described
and synoptic hydrographic, nutrient, and meteorological
data were analyzed to identify factors that may influence
Phaeocystis abundance. The maximum Phaeocystis abundance
was 14 × 106 cells L−1 (10 Apr 2008). It was frequently
(5 of 8 years) absent prior to year 2000, but not thereafter.
Seasonally, it first appeared in February to early March,
reached peak abundance in mid-April, and persisted until
May or early June for a duration of 0–112 days (mean 34 days).
A long-term alternation between Phaeocystis and centric diatom
abundance was apparent, suggesting winter-spring selection
of either Phaeocystis or centric diatoms. Phytoplankton
community analysis suggested that blooms affected the rest of the phytoplankton community. Phaeocystis blooms were
manifest as a substantial increase in particulate nutrients above
normal levels. Phaeocystis blooms were preceded in February
by a slightly elevated concentration of NO3 (9.3 vs. 6.5 μM
when absent) and PO4 (0.99 vs. 0.79 μM when absent).
Blooms were also preceded by elevated ratios of NO3/PO4,
NO3/Si, and PO4/Si, and warmer, saltier waters reflecting
reduced river discharge. The correlation with salinity and
river discharge suggests that Phaeocystis bloom variability
is partially determined by annually varying circulation processes
that determine the degree of low nutrient, low salinity coastal
water intrusion into Massachusetts Bay.