Isolation and Characterization of Human Trophoblast Side-Population (SP) Cells in Primary Villous Cytotrophoblasts and HTR-8/SVneo Cell Line

Recently, numerous studies have identified that immature cell populations including stem cells and progenitor cells can be found among “side-population” (SP) cells. Although SP cells isolated from some adult tissues have been reported elsewhere, isolation and characterization of human trophoblast SP remained to be reported. In this study, HTR-8/SVneo cells and human primary villous cytotrophoblasts (vCTBs) were stained with Hoechst 33342 and SP and non-SP (NSP) fractions were isolated using a cell sorter. A small population of SP cells was identified in HTR-8/SVneo cells and in vCTBs. SP cells expressed several vCTB-specific markers and failed to express syncytiotrophoblast (STB) or extravillous cytotrophopblast (EVT)-specific differentiation markers. SP cells formed colonies and proliferated on mouse embryonic fibroblast (MEF) feeder cells or in MEF conditioned medium supplemented with heparin/FGF2, and they also showed long-term repopulating property. SP cells could differentiate into both STB and EVT cell lineages and expressed several differentiation markers. Microarray analysis revealed that IL7R and IL1R2 were exclusively expressed in SP cells and not in NSP cells. vCTB cells sorted as positive for both IL7R and IL1R2 failed to express trophoblast differentiation markers and spontaneously differentiated into both STB and EVT in basal medium. These features shown by the SP cells suggested that IL7R and IL1R2 are available as markers to detect the SP cells and that vCTB progenitor cells and trophoblast stem cells were involved in the SP cell population

Dynamics of magnetization at infinite temperature in a Heisenberg spin chain

Understanding universal aspects of quantum dynamics is an unresolved problem in statistical mechanics. In particular, the spin dynamics of the 1D Heisenberg model were conjectured to belong to the Kardar-Parisi-Zhang (KPZ) universality class based on the scaling of the infinite-temperature spin-spin correlation function. In a chain of 46 superconducting qubits, we study the probability distribution, $P(\mathcal{M})$, of the magnetization transferred across the chain's center. The first two moments of $P(\mathcal{M})$ show superdiffusive behavior, a hallmark of KPZ universality. However, the third and fourth moments rule out the KPZ conjecture and allow for evaluating other theories. Our results highlight the importance of studying higher moments in determining dynamic universality classes and provide key insights into universal behavior in quantum systems

Proceedings of the 13th annual conference of INEBRIA

CITATION: Watson, R., et al. 2016. Proceedings of the 13th annual conference of INEBRIA. Addiction Science & Clinical Practice, 11:13, doi:10.1186/s13722-016-0062-9.The original publication is available at https://ascpjournal.biomedcentral.comENGLISH SUMMARY : Meeting abstracts.https://ascpjournal.biomedcentral.com/articles/10.1186/s13722-016-0062-9Publisher's versio

The design and control of active ankle-foot orthoses

Ankle foot orthoses (AFOs) can be used to ameliorate the impact of impairments to the lower limb neuromuscular motor system that affect gait. Existing AFO technologies include passive devices with fixed and articulated joints, semi-active devices that modulate damping at the joint and active devices that make use of a variety of technologies to produce power to move the foot. Emerging technologies provide a vision for fully powered, untethered AFOs. In this dissertation, a novel portable powered ankle-foot orthosis (PPAFO) cabable of providing un-tethered assistance during gait is presented. The PPAFO provides both plantarflexor and dorsiflexor torque assistance via a bi-directional pneumatic rotary actuator. The system uses a portable pneumatic power source (compressed CO2 bottle) and embedded electronics to control the motion of the foot. Experimental data from two impaired and five healthy subjects were collected to demonstrate design functionality. The impaired subjects had bilateral impairments to the lower legs that caused weakness to the plantarflexors, in one case, and to the dorsiflexors in the other. Data from the healthy walkers demonstrated the PPAFO???s capability to provide correctly timed plantarflexor and dorsiflexor assistance during gait. The results from the impaired subjects demonstrated the PPAFO???s ability to provide functional assistance during gait. Additionally, this dissertation presented a modeling and control approach to address limitations present in the PPAFO through the introduction of a new hardware configuration and new control architecture. A combined model consisting of both the PPAFO and the human foot and shank segments was first derived and validated. Next, the current and the new PPAFO system configurations were evaluated both in simulation and experimentally during three simplified functional gait tasks: (1) motion control of the foot at the start of the gait cycle, (2) plantarflexor torque assistance during late stance, and (3) dorsiflexor position control of the foot during swing. The resulting analysis showed that the new system configuration both outperformed and was more efficient than the current PPAFO configuration. The stringent design requirements of light weight, small size, high efficiency and low noise make the creation of daily wear assist devices challenging, but once such devices appear they will present new opportunities for clinical treatment of gait abnormalities

Estimating System State During Human Walking with a Powered Ankle-Foot Orthosis

This paper presents a state estimator that reliably detects gait events during human walking with a portable powered ankle-foot orthosis (AFO), based only on measurements of the ankle angle and of contact forces at the toe and heel. Effective control of the AFO critically depends on detecting these gait events. A common approach detects gait events simply by checking if each measurement exceeds a given threshold. Our approach uses cross correlation between a window of past measurements and a learned model to estimate the configuration of the human walker, and detects gait events based on this estimate. We tested our approach in experiments with five healthy subjects and with one subject that had neuromuscular impairment. Using motion capture data for reference, we compared our approach to one based on thresholding and to another common one based on k -nearest neighbors. The results showed that our approach reduced the RMS error by up to 40% for the impaired subject and up to 49% for the healthy subjects. Moreover, our approach was robust to perturbations due to changes in walking speed and to control actuation

Environmental Enrichment Factors Associated with the Activity Level of Bottlenose Dolphins under Professional Care

Environmental enrichment can be used to improve the welfare of dolphins in zoos and aquariums. Bottlenose dolphins under professional care are typically provided with a range of enrichment that has a variety of features and levels of complexity at various frequencies. In the present study, a subset of data from a larger study entitled “Towards understanding the welfare of cetaceans in zoos and aquariums” (colloquially called the Cetacean Welfare Study) was used to examine the relationship between activity level and enrichment buoyancy as well as enrichment provisioning schedules. Survey data were collected from accredited zoos and aquariums related to the types of enrichment provided to the dolphins and the frequency and duration they were supplied. Non-invasive bio-logging devices were used to record the dolphin kinematics one day per week over the course of two five-week data collection periods. Activity level related positively with the total duration of time non-stationary enrichment was provided. In addition, providing a larger number of enrichment types each between 26% and 50% of the days in a month (i.e., rotating many different types of enrichment across days on a moderate schedule) was positively related to activity level. Activity level was negatively related to the number of times sinking enrichment was provided. Understanding how the temporal schedule and features of various types of enrichment are related to activity levels will aid in developing progressively more effective enrichment programs

Underwater behavior of humpback whales in a western North Atlantic foraging area

In July of 2004 we used synchronous motion, digital acoustic recording tags (DTAGs) to investigate the underwater behavior of humpback whales in the Great South Channel. Tag attachments to four animals resulted in ~50 hours of data in water depths from 70 - 90m. We conducted a detailed analysis of dive patterns, including apparent bottom feeding and associated sounds. We partitioned dive records into 3 categories: descent, ascent, and at-depth. All four animals traversed a majority of the descent in freeglide (86%, 78%, 84%, and 70%), and fluke-strokes were confined to the upper portions of the water column [ending at: -11.2 m (0.22), -16.1 m (2.9), -12.0 m (2.9), -25.5 m (6.8)]. On ascent, fluke-strokes were in much more of the water column [ending at: -19.9 m (2.4), -39.6 m (11.0), -24.4 m (6.0), -28.6 m (5.6)], but animals still traversed a substantial portion in free-glide (24%, 54%, 33%, and 33%). Thus, descent and ascent demonstrated buoyancy related adaptations for locomotor efficiency. At-depth behavior consisted primarily of presumed foraging activity. In 95% of flat-bottomed dives whales exhibited a characteristic “side-roll” behavior. Side-rolls involved the animal rolling laterally more than 40º from dorsal and holding that position for a consistent duration, usually more than 10 seconds. Mean number of side-rolls per dive for each animal was 2.84, 6.7, 3.15, and 4.32. Two animals had a consistent mean sideroll duration (in seconds), while mean duration for the other two was more varied [17.7 s (4.0), 24.6 s (11.5), 13.1 s (2.6), 19.1 s (14.4)]. For each animal the angle of roll was consistent [96.7º (7.7), -73º (17.6), - 80.5º (3.7), -84.2º (23)], and they maintained a head-down pitch angle [28.5º (3.2), 24.4º (9.3), 10.7º (4.8), 32.2º (2.6)]. Between side-rolls, animals returned to a dorsal-ventral orientation. Side-rolls occurred at or within a few meters of the sea floor and were often preceded by a stereotypic sound. We speculate that side-rolls indicate periods of consumatory feeding. Data have management implications with regards to whale entanglement and fishing gear modification

Environmental Enrichment Factors Associated with the Activity Level of Bottlenose Dolphins under Professional Care

Environmental enrichment can be used to improve the welfare of dolphins in zoos and aquariums. Bottlenose dolphins under professional care are typically provided with a range of enrichment that has a variety of features and levels of complexity at various frequencies. In the present study, a subset of data from a larger study entitled “Towards understanding the welfare of cetaceans in zoos and aquariums” (colloquially called the Cetacean Welfare Study) was used to examine the relationship between activity level and enrichment buoyancy as well as enrichment provisioning schedules. Survey data were collected from accredited zoos and aquariums related to the types of enrichment provided to the dolphins and the frequency and duration they were supplied. Non-invasive bio-logging devices were used to record the dolphin kinematics one day per week over the course of two five-week data collection periods. Activity level related positively with the total duration of time non-stationary enrichment was provided. In addition, providing a larger number of enrichment types each between 26% and 50% of the days in a month (i.e., rotating many different types of enrichment across days on a moderate schedule) was positively related to activity level. Activity level was negatively related to the number of times sinking enrichment was provided. Understanding how the temporal schedule and features of various types of enrichment are related to activity levels will aid in developing progressively more effective enrichment programs