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Investigation of c-Jun N-terminal Kinase 2 Regulation
JNK2). This protein is unique in that it can autophosphorylate, or phosphorylate itself. It was found that these proteins tend to form aggregates of four, or tetramers, when inactive and remain as single units, or monomers, when active. In glioblastoma and lung carcinoma cells, JNK2s are reported to be constitutively, or always, active. This study aimed to investigate a selection of JNK2 mutations determine which of these mutations can alter JNK2 activity and oligomerization state.
Results from size-exclusion chromatography and light scattering analysis (SEC-LS) suggested that while the wild type JNK2 exists as a mixture of monomers and tetramers, the activation loop chimera mutant (C177G/N179S) exists only as monomers. Additionally, phosphorylation assay analysis showed increased autophosphorylation activity of the activation loop chimera mutant compared to the wild type. These results suggest that the activation loop may be involved in the mechanism of JNK2 regulation. Elucidation of MAPK regulation mechanisms may allow more effective cancer therapy screening and increase overall understanding of tumor growth mechanisms.Molecular Bioscience
An Intervening Ethical Governor for a Robot Mediator in Patient-Caregiver Relationships
© Springer International Publishing AG 2015DOI: 10.1007/978-3-319-46667-5_6Patients with Parkinsonâs disease (PD) experience challenges when interacting with
caregivers due to their declining control over their musculature. To remedy those challenges, a
robot mediator can be used to assist in the relationship between PD patients and their caregivers.
In this context, a variety of ethical issues can arise. To overcome one issue in particular,
providing therapeutic robots with a robot architecture that can ensure patientsâ and caregiversâ
dignity is of potential value. In this paper, we describe an intervening ethical governor for a
robot that enables it to ethically intervene, both to maintain effective patientâcaregiver
relationships and prevent the loss of dignity
Effects of Obesity on Stability Control among Young Adults in Responding to a Simulated Slip Induced in Gait
Falls among older adults present a significant medical, societal, and economic challenge affecting not only the frail or impaired, but the active and vigorous. Falls initiated by slip account for about 25% of all falls among older people. Obesity has been regarded as a significant health problem. It has been reported that obesity causes muscle weakness, abnormal body mass distribution, and postural instability. Dynamic gait stability has been identified as a key factor leading to falls during slip in gait among both young and old adults. Despite the fact that obese individuals suffer higher risk of falls compared to non-obese individuals, little is known about the possible impact of obesity upon dynamic gait stability control. The purpose of this study was to examine if and to what extent the dynamic gait stability control during a slip-initiated fall differs between young obese and non-obese individuals. Twelve healthy young adults including 6 non-obese and 6 obese participated in the study approved by the Institutional Review Board. The subjects were classified as obese with a body mass index â„ 30 kg/m2 and a body fat percentage â„ 30%. Subjects were informed that they would be performing normal walking initially and would experience simulated slip later without knowing when, where, and how that would happen. They were also told to try to recover their balance on any slip incidence and then to continue walking. All trials were performed on an Activestep treadmill and were under protection of a safety harness connected to a load cell and then to an overhead arch. After 6-8 normal walking trials, a 24-cm and 12 m/s2 unexpected slip was induced within 0.2 s. A fall in responding to the slip was identified if the load cell force exceeded 30% of the subjectâs body weight. Dynamic gait stability was calculated, at touchdown (TD) of the leading foot and liftoff (LO) of the trailing foot upon the slip trial, by using the collected center of mass kinematics. Independent t-tests results indicated that dynamic stability control did not display significant between-group difference at TD (immediately before the slip onset) upon the slip trial (0.86 ± 0.03 vs. 0.86 ± 0.04, p \u3e 0.05). However, the non-obese group was more stable than the obese group at LO (~180 ms after slip onset) as evidenced by the higher stability values within the non-obese group in comparison with the ones in obese group (0.14 ± 0.03 vs. 0.01 ± 0.08, p \u3c 0.01). As a result of the better control of the dynamic stability, fewer subjects in the non-obese group fell than in the obese group when exposure to the unannounced slip. In particular, five out of 6 (83%) participants in the obese group fell while only one out of 6 (17%) fell within the non-obese group (p \u3c 0.05). Our results revealed that obesity affects the dynamic stability control and consequently increases the likelihood of slip-related falls among young adults during gait. Findings from this study could provide some guidance to train individuals with obesity to reduce their risk of falls
The Benefits of Robot Deception in Search and Rescue: Computational Approach for Deceptive Action Selection via Case-Based Reasoning
© 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.DOI: 10.1109/SSRR.2015.7443002By increasing the use of autonomous rescue robots
in search and rescue (SAR), the chance of interaction between
rescue robots and human victims also grows. More specifically,
when autonomous rescue robots are considered in SAR, it is
important for robots to handle sensitively human victimsâ
emotions. Deception can potentially be used effectively by
robots to control human victimsâ fear and shock as used by
human rescuers. In this paper, we introduce robotic deception
in SAR contexts and present a novel computational approach
for an autonomous rescue robotâs deceptive action selection
mechanism
Taxonomy of \u3ci\u3eEchinostoma revolutum\u3c/i\u3e and 37-Collar-Spined \u3ci\u3eEchinostoma\u3c/i\u3e spp.: A Historical Review
Echinostoma flukes armed with 37 collar spines on their head collar are called as 37-collar-spined Echinostoma spp. (group) or âEchinostoma revolutum groupâ. At least 56 nominal species have been described in this group. However, many of them were morphologically close to and difficult to distinguish from the other, thus synonymized with the others. However, some of the synonymies were disagreed by other researchers, and taxonomic debates have been continued. Fortunately, recent development of molecular techniques, in particular, sequencing of the mitochondrial (nad1 and cox1) and nuclear genes (ITS region; ITS1-5.8S-ITS2), has enabled us to obtain highly useful data on phylogenetic relationships of these 37-collar-spined Echinostoma spp. Thus, 16 different species are currently acknowledged to be valid worldwide, which include E. revolutum, E. bolschewense, E. caproni, E. cinetorchis, E. deserticum, E. lindoense, E. luisreyi, E. mekongi, E. miyagawai, E. nasincovae, E. novaezealandense, E. paraensei, E. paraulum, E. robustum, E. trivolvis, and Echinostoma sp. IG of Georgieva et al., 2013. The validity of the other 10 species is retained until further evaluation, including molecular analyses; E. acuticauda, E. barbosai, E. chloephagae, E. echinatum, E. jurini, E. nudicaudatum, E. parvocirrus, E. pinnicaudatum, E. ralli, and E. rodriguesi. In this review, the history of discovery and taxonomic debates on these 26 valid or validity-retained species are briefly reviewed
The Impact of Patchy Reionization on Ultra-faint Dwarf Galaxies
We investigate how patchy reionization affects the star formation history
(SFH) and stellar metallicity of ultra-faint dwarf galaxies (UFDs). Patchy
reionization refers to varying ultraviolet (UV) background strengths depending
on a galaxy's environment. Recent observations highlight the significance of
this effect on UFDs, as UFDs can have different SFHs depending on their
relative position with respect to their host halo during the period of
reionization. However, most cosmological hydrodynamic simulations do not
consider environmental factors such as patchy reionization, and the effect of
reionization is typically applied homogeneously. Using a novel approach to
implement patchy reionization, we show how SFHs of simulated UFDs can change.
Our cosmological hydrodynamic zoom-in simulations focus on UFD analogs with
M_vir~10^9solar mass, M_star < 10^5 solar mass at . We find that patchy
reionization can weaken the effect of reionization by two orders of magnitude
up to , enabling late star formation in half of the simulated UFDs, with
quenching times 460 Myr later than those with homogeneous reionization.
We also show that halo merger and mass assembly can affect the SFHs of
simulated UFDs, in addition to patchy reionization. The average stellar
iron-to-hydrogen ratio, [Fe/H], of the simulated UFDs with patchy reionization
increases by 0.22-0.42 dex. Finally, our findings suggest that patchy
reionization could be responsible for the extended SFHs of Magellanic UFDs
compared to non-Magellanic UFDs.Comment: 27 pages, 16 figures, Accepted for publication in Astrophysical
Journa
The ancient phosphatidylinositol 3-kinase signaling system is a master regulator of energy and carbon metabolism in algae
Algae undergo a complete metabolic transformation under stress by arresting cell growth, inducing autophagy and hyperaccumulating biofuel precursors such as triacylglycerols and starch. However, the regulatory mechanisms behind this stress-induced transformation are still unclear. Here, we use biochemical, mutational, and âomicsâ approaches to demonstrate that PI3K signaling mediates the homeostasis of energy molecules and influences carbon metabolism in algae. In Chlamydomonas reinhardtii, the inhibition and knockdown (KD) of algal class III PI3K led to significantly decreased cell growth, altered cell morphology, and higher lipid and starch contents. Lipid profiling of wild-type and PI3K KD lines showed significantly reduced membrane lipid breakdown under nitrogen starvation (-N) in the KD. RNA-seq and network analyses showed that under -N conditions, the KD line carried out lipogenesis rather than lipid hydrolysis by initiating de novo fatty acid biosynthesis, which was supported by tricarboxylic acid cycle down-regulation and via acetyl-CoA synthesis from glycolysis. Remarkably, autophagic responses did not have primacy over inositide signaling in algae, unlike in mammals and vascular plants. The mutant displayed a fundamental shift in intracellular energy flux, analogous to that in tumor cells. The high free fatty acid levels and reduced mitochondrial ATP generation led to decreased cell viability. These results indicate that the PI3K signal transduction pathway is the metabolic gatekeeper restraining biofuel yields, thus maintaining fitness and viability under stress in algae. This study demonstrates the existence of homeostasis between starch and lipid synthesis controlled by lipid signaling in algae and expands our understanding of such processes, with biotechnological and evolutionary implications.Ministry of Science, ICT and Future Planning 2015M3A6A2065697Ministry of Oceans and Fisheries 2015018
TimeKit: A Time-series Forecasting-based Upgrade Kit for Collaborative Filtering
Recommender systems are a long-standing research problem in data mining and
machine learning. They are incremental in nature, as new user-item interaction
logs arrive. In real-world applications, we need to periodically train a
collaborative filtering algorithm to extract user/item embedding vectors and
therefore, a time-series of embedding vectors can be naturally defined. We
present a time-series forecasting-based upgrade kit (TimeKit), which works in
the following way: it i) first decides a base collaborative filtering
algorithm, ii) extracts user/item embedding vectors with the base algorithm
from user-item interaction logs incrementally, e.g., every month, iii) trains
our time-series forecasting model with the extracted time-series of embedding
vectors, and then iv) forecasts the future embedding vectors and recommend with
their dot-product scores owing to a recent breakthrough in processing
complicated time-series data, i.e., neural controlled differential equations
(NCDEs). Our experiments with four real-world benchmark datasets show that the
proposed time-series forecasting-based upgrade kit can significantly enhance
existing popular collaborative filtering algorithms.Comment: Accepted at IEEE BigData 202
Effects of community health volunteers on infectious diseases of children under five in Volta Region, Ghana: study protocol for a cluster randomized controlled trial.
BACKGROUND: In many low- and middle-income countries, community health volunteers (CHVs) are employed as a key element of the public health system in rural areas with poor accessibility. However, few studies have assessed the effectiveness of CHVs in improving child health in sub-Saharan Africa through randomized controlled trials. The present study aims to measure the impact of health promotion and case management implemented by CHVs on the health of under-5 children in Ghana. METHODS/DESIGN: This study presents the protocol of a cluster-randomized controlled trial assessing the impacts of CHVs, in which the community was used as the randomization unit. A phase-in design will be adopted, and the intervention arm will be implemented in the intervention arm during the first phase and in the control arm during the second phase. The key intervention is the deployment of CHVs, who provide health education, provide oral rehydration solutions and zinc tablets to children with diarrhea, and diagnose malaria using a thermometer and a rapid diagnostic test kit during home visits. The primary endpoints of the study are the prevalence of diarrhea and fever/malaria in children under 5Â years of age, as well as the proportion of affected children receiving case management for diarrhea and malaria. The first and second rounds of household surveys to collect data will be conducted in the first phase, and the final round will be conducted during the second phase. DISCUSSION: With growing attention paid to the roles of CHVs as an essential part of the community health system in low-income countries, this study will contribute valuable information to the body of knowledge on the effects of CHVs. TRIAL REGISTRATION: ISRCTN49236178 . (June 16th, 2015)
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