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Article printed in The Villager

Manatees are aquatic mammals with voracious appetites. They rely on sea grass as the main
food source, and often spend up to eight hours a day grazing. They move slow and frequently
stay in groups (i.e. aggregations) in shallow water to search for food, making them vulnerable to
environment change and other risks. Accurate counting manatee aggregations within a region is not
only biologically meaningful in observing their habit, but also crucial for designing safety rules for
boaters, divers, etc., as well as scheduling nursing, intervention, and other plans. In this paper, we
propose a deep learning based crowd counting approach to automatically count number of manatees
within a region, by using low quality images as input. Because manatees have unique shape and
they often stay in shallow water in groups, water surface reflection, occlusion, camouflage etc.
making it difficult to accurately count manatee numbers. To address the challenges, we propose to
use Anisotropic Gaussian Kernel (AGK), with tunable rotation and variances, to ensure that density
functions can maximally capture shapes of individual manatees in different aggregations. After
that, we apply AGK kernel to different types of deep neural networks primarily designed for crowd
counting, including VGG, SANet, Congested Scene Recognition network (CSRNet), MARUNet etc. to
learn manatee densities and calculate number of manatees in the scene. By using generic low quality
images extracted from surveillance videos, our experiment results and comparison show that AGK
kernel based manatee counting achieves minimum Mean Absolute Error (MAE) and Root Mean Square
Error (RMSE). The proposed method works particularly well for counting manatee aggregations in
environments with complex background.

Individuals who have suffered neurotrauma like a stroke or brachial plexus injury
often experience reduced limb functionality. Soft robotic exoskeletons have
been successful in assisting rehabilitative treatment and improving activities of
daily life but restoring dexterity for tasks such as playing musical instruments
has proven challenging. This research presents a soft robotic hand exoskeleton
coupled with machine learning algorithms to aid in relearning how to play the
piano by ‘feeling’ the difference between correct and incorrect versions of the
same song. The exoskeleton features piezoresistive sensor arrays with 16 taxels
integrated into each fingertip. The hand exoskeleton was created as a single unit,
with polyvinyl acid (PVA) used as a stent and later dissolved to construct the
internal pressure chambers for the five individually actuated digits. Ten variations
of a song were produced, one that was correct and nine containing rhythmic
errors. To classify these song variations, Random Forest (RF), K-Nearest Neighbor
(KNN), and Artificial Neural Network (ANN) algorithms were trained with data
from the 80 taxels combined from the tactile sensors in the fingertips. Feeling the
differences between correct and incorrect versions of the song was done with
the exoskeleton independently and while the exoskeleton was worn by a person.
Results demonstrated that the ANN algorithm had the highest classification
accuracy of 97.13% ± 2.00% with the human subject and 94.60% ± 1.26% without.
These findings highlight the potential of the smart exoskeleton to aid disabled
individuals in relearning dexterous tasks like playing musical instruments.

Despite evidence of their importance to marine ecosystems, at least 32% of all chondrichthyan
species are estimated or assessed as threatened with extinction. In addition to the logistical
difficulties of effectively conserving wide-ranging marine species, shark conservation is
believed to have been hindered in the past by public perceptions of sharks as dangerous to
humans. Shark Week is a high-profile, international programming event that has potentially
enormous influence on public perceptions of sharks, shark research, shark researchers,
and shark conservation. However, Shark Week has received regular criticism for poor factual
accuracy, fearmongering, bias, and inaccurate representations of science and scientists.
This research analyzes the content and titles of Shark Week episodes across its entire
32 years of programming to determine if there are trends in species covered, research techniques
featured, expert identity, conservation messaging, type of programming, and portrayal
of sharks. We analyzed titles from 272 episodes (100%) of Shark Week programming
and the content of all available (201; 73.9%) episodes. Our data demonstrate that the majority
of episodes are not focused on shark bites, although such shows are common and many
Shark Week programs frame sharks around fear, risk, and adrenaline. While criticisms of
disproportionate attention to particular charismatic species (e.g. great whites, bull sharks,
and tiger sharks) are accurate and supported by data, 79 shark species have been featured
briefly at least once. Shark Week’s depictions of research and of experts are biased towards
a small set of (typically visual and expensive) research methodologies and (mostly white,
mostly male) experts, including presentation of many white male non-scientists as scientific
experts. While sharks are more often portrayed negatively than positively, limited conservation
messaging does appear in 53% of episodes analyzed. Results suggest that as a whole,
while Shark Week is likely contributing to the collective public perception of sharks as bad,
even relatively small alterations to programming decisions could substantially improve the
presentation of sharks and shark science and conservation issues.

Increased neuronal excitability causes seizures with debilitating symptoms. Effective and noninvasive treatments are limited
for easing symptoms, partially due to the complexity of the disorder and lack of knowledge of specific molecular faults. An
unexplored, novel target for seizure therapeutics is the cGMP/protein kinase G (PKG) pathway, which targets downstream
K+
channels, a mechanism similar to Retigabine, a recently FDA-approved antiepileptic drug. Our results demonstrate that
increased PKG activity decreased seizure duration in C. elegans utilizing a recently developed electroconvulsive seizure
assay. While the fly is a well-established seizure model, C. elegans are an ideal yet unexploited model which easily uptakes
drugs and can be utilized for high-throughput screens. In this study, we show that treating the worms with either a potassium
channel opener, Retigabine or published pharmaceuticals that increase PKG activity, significantly reduces seizure recovery
times. Our results suggest that PKG signaling modulates downstream K+
channel conductance to control seizure recovery
time in C. elegans. Hence, we provide powerful evidence, suggesting that pharmacological manipulation of the PKG signaling
cascade may control seizure duration across phyla.

Restriction of dietary food without malnutrition robustly extends lifespan in more than
twenty species. It was also reported that fruit flies (Drosophila melanogaster) deficient in
olfactory function live longer and that the longevity induced by food restriction is partially
due to decreased olfaction. These observations suggest food assimilation through the gastrointestinal
tract and food smell detected by olfactory neurons influence lifespan. The
insulin growth factor signaling pathway is regulated by nutrient levels and has been shown
to mediate the lifespan extension conferred by food restriction and defective gustatory neurons
in the nematode Caenorhabditis elegans. However, the mechanism remains unclear.
Autophagy is a lysosomal degradation pathway and is sensitive to nutrient availability. We
found autophagy activity in the intestine and food sensory neurons acts in parallel to mediate
food restriction and insulin signaling regulated lifespan extension in Caenorhabditis elegans.
Moreover, intestinal and neuronal autophagy converge on unidentified neurons to
control the secretion of neuropeptides that regulate lifespan. These data suggest autophagy is an essential component in a neuroendocrine pathway that coordinates how environmental
food cues detected by sensory neurons and food nutrients assimilated by the intestine
influence lifespan. These findings may contribute to understanding the aging process in
mammals.

The microscopic nematode Caenorhabditis elegans has emerged as a valuable model for understanding the molecular and cellular basis of neurological disorders. The worm offers important physiological similarities to mammalian models such as conserved neuron morphology, ion channels, and neurotransmitters. While a wide-array of behavioral assays are available in C. elegans, an assay for electroshock/electroconvulsion remains absent. Here, we have developed a quantitative behavioral method to assess the locomotor response following electric shock in C. elegans. Electric shock impairs normal locomotion, and induces paralysis and muscle twitching; after a brief recovery period, shocked animals resume normal locomotion. We tested electric shock responses in loss-of-function mutants for unc-25, which encodes the GABA biosynthetic enzyme GAD, and unc-49, which encodes the GABAA receptor. unc-25 and unc-49 mutants have decreased inhibitory GABAergic transmission to muscles, and take significantly more time to recover normal locomotion following electric shock compared to wild-type. Importantly, increased sensitivity of unc-25 and unc-49 mutants to electric shock is rescued by treatment with antiepileptic drugs, such as retigabine. Additionally, we show that pentylenetetrazol (PTZ), a GABAA receptor antagonist and proconvulsant in mammalian and C. elegans seizure models, increases susceptibility of worms to electric shock.