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Plantain (Musa parasidiaca) is a perishable fruit that needs to be processed into flour to extend its shelflife. It is therefore essential to develop specifications for drying Musa parasidiaca pulp to obtain high quality flour and reduce wastage. The study specifically examined functional properties such as bulk density, least gelation concentration, swelling power, oil absorption capacity, tapped density and pH of the unripe Musa parasidiaca flour. Additionally, the proximate composition such as moisture content, ash, crude protein, crude fibre carbohydrate and crude fat were also investigated. The results showed that the method of drying has a significant effect on the carbohydrate and moisture content of the unripe Musa parasidiaca flour. As regard to the crude protein, it was revealed that there were no significant differences between microwave dried (3.75 %) and sun dried (3.84 %) flours. Bulk density of the unripe Musa parasidiaca flour samples dried in the microwave dryer (MD), sun drying (SD) and oven dryer (OD) were 0.66 g/mL, 0.60 g/mL and 0.77 g/mL respectively. It was observed that all the three methods of drying significantly impacted on the bulk density of the unripe Musa parasidiaca flour. There were also marked differences in the rehydration ratios (RR), and the moisture diffusivities of the various Musa parasidiaca flours. The study concludes that the colour of the MD unripe Musa parasidiaca flour was significantly different from that of the SD unripe Musa parasidiaca flour.

# Background The Y-Balance Test (YBT) assesses dynamic stability and neuromuscular control of the lower extremity. Several authors have analyzed kinematic predictors of YBT performance with conflicting results, but the influence of kinetic factors is not well understood. # Purpose To examine kinematic predictors of YBT performance and determine the joint kinetics which predict YBT performance. # Study Design Cross-sectional study. # Methods Thirty-one physically active individuals performed YBT trials on a force plate while whole body kinematics were recorded using a motion capture system. Sagittal, frontal, and transverse plane joint kinematics and joint moments were calculated at maximum reach in each YBT reach direction. Variables correlated with reach distances at the *p* \< 0.2 level were entered into a stepwise linear regression. # Results In the anterior direction, knee flexion and torso rotation (*R^2^*=0.458, *p*\

Striatal interneurons and spiny projection (SP) neurons are differentially tuned to spectral components of their input. Previous studies showed that spike responses of somatostatin/NPY-expressing low threshold spike (LTS) interneurons have broad frequency tuning, setting these cells apart from other striatal GABAergic interneurons and SP neurons. We investigated the mechanism of LTS interneuron spiking resonance and its relationship to non-spiking membrane impedance resonance, finding that abolition of impedance resonance did not alter spiking resonance. Because LTS interneurons are pacemakers whose rhythmic firing is perturbed by synaptic input, we tested the hypothesis that their spiking resonance arises from their phase resetting properties. Phase resetting curves (PRCs) were measured in LTS interneurons and SP neurons and used to make phase-oscillator models of both cell types. The models reproduced the broad tuning of LTS interneurons, and the differences from SP neurons. The spectral components of the PRC predicted each cell’s sensitivity to corresponding input frequencies. LTS interneuron PRCs contain larger high-frequency components than SP neuron PRCs, providing enhanced responses to input frequencies above the cells’ average firing rates. Thus, LTS cells can be entrained by input oscillations to which SP neurons are less responsive. These findings suggest that feedforward inhibition by LTS interneurons may regulate SP neurons’ entrainment by oscillatory afferents.

Oscillatory input to networks, as indicated by field potentials, must entrain neuronal firing to be a causal agent in brain activity. Even when the oscillatory input is prominent, entrainment of firing is not a foregone conclusion but depends on the intrinsic dynamics of the postsynaptic neurons, including cell type-specific resonances, and background firing rates. Within any local network of neurons, only a subset of neurons may have their firing entrained by an oscillating synaptic input, and oscillations of different frequency may engage separate subsets of neurons.

The identity and legitimacy of campus police officers is often difficult to define, largely due to their obvious connection to the educational environment. With the lack of research on campus police in general, and their legitimacy as a law enforcement entity in specific, how these officers perceive themselves and, just as importantly, how they believe others perceive them, becomes questionable and may have a distinct impact on their performance of duties and their interactions with the campus community and other law enforcement personnel. This study considers self-perceived levels of legitimacy of campus police officers employed at four statutorily defined campus police departments in the State of Rhode Island from a review of various issues of perceptual self-worth, their effects on officer morale, and their impact on levels of service to the campus community. Findings indicate that while they are, indeed, granted legislative police authority that is comparable to their more public counterparts, campus law enforcement officers perceive a lack of legitimization and support from their community; have high levels of self-perceived feelings of marginalization; and face an ever uphill battle in their efforts to obtain the same levels of legitimacy as their traditional counterparts.

We used phase resetting methods to predict firing patterns of rat subthalamic nucleus (STN) neurons when their rhythmic firing was densely perturbed by noise. We applied sequences of contiguous brief (0.5-2 ms) current pulses with amplitudes drawn from a Gaussian distribution (10-100 pA standard deviation) to autonomously firing STN neurons in slices. Current noise sequences increased the variability of spike times with little or no effect on the average firing rate. We measured the infinitesimal phase resetting curve (PRC) for each neuron using a noise-based method. A phase model consisting of only a firing rate and PRC was very accurate at predicting spike timing, accounting for more than 80% of spike time variance and reliably reproducing the spike-to-spike pattern of irregular firing. An approximation for the evolution of phase was used to predict the effect of firing rate and noise parameters on spike timing variability. It quantitatively predicted changes in variability of interspike intervals with variation in noise amplitude, pulse duration and firing rate over the normal range of STN spontaneous rates. When constant current was used to drive the cells to higher rates, the PRC was altered in size and shape and accurate predictions of the effects of noise relied on incorporating these changes into the prediction. Application of rate-neutral changes in conductance showed that changes in PRC shape arise from conductance changes known to accompany rate increases in STN neurons, rather than the rate increases themselves. Our results show that firing patterns of densely perturbed oscillators cannot readily be distinguished from those of neurons randomly excited to fire from the rest state. The spike timing of repetitively firing neurons may be quantitatively predicted from the input and their PRCs, even when they are so densely perturbed that they no longer fire rhythmically.

Intracranial depth electrode EEG records of 478 seizures, recorded in 68 patients undergoing diagnostic monitoring with depth electrodes, were evaluated to investigate the correlates of electrographic onset patterns in patients with temporal lobe seizures. The seizure onsets in 78% of these patients were identified as either hypersynchronous onsets, beginning with low-frequency, high-amplitude spikes, or low-voltage fast (LVF) onsets, increasing in amplitude as the seizure progressed. The number of patients (35) having hypersynchronous seizure onsets was nearly twice that of patients (18) having LVF onsets. Three major differences were seen among patients with the two seizure-onset patterns. When compared with patients having LVF onsets, patients with hypersynchronous seizure onsets had a significantly greater probability of having (1) focal rather than regional seizure onsets (p

We study synchronization phenomenon of coupled neuronal oscillators using the theory of weakly coupled oscillators. The role of sudden jumps in the phase response curve profiles found in some experimental recordings and models on the ability of coupled neurons to exhibit synchronous and antisynchronous behavior is investigated, when the coupling between the neurons is electrical. The level of jumps in the phase response curve at either end, spike width and frequency of voltage time course of the coupled neurons are parameterized using piecewise linear functional forms, and the conditions for stable synchrony and stable antisynchrony in terms of those parameters are computed analytically. The role of the peak position of the phase response curve on phase-locking is also investigated.

High frequency deep-brain stimulation of the subthalamic nucleus (DBS) relieves many of the symptoms of Parkinson's disease in humans and animal models. Although the treatment has seen widespread use, its therapeutic mechanism remains paradoxical. The subthalamic nucleus is excitatory, so its stimulation at rates higher than its normal firing rate should worsen the disease by increasing subthalamic excitation of the globus pallidus. The therapeutic effectiveness of DBS is also frequency and intensity sensitive, and the stimulation must be periodic; aperiodic stimulation at the same mean rate is ineffective. These requirements are not adequately explained by existing models, whether based on firing rate changes or on reduced bursting. Here we report modeling studies suggesting that high frequency periodic excitation of the subthalamic nucleus may act by desynchronizing the firing of neurons in the globus pallidus, rather than by changing the firing rate or pattern of individual cells. Globus pallidus neurons are normally desynchronized, but their activity becomes correlated in Parkinson's disease. Periodic stimulation may induce chaotic desynchronization by interacting with the intrinsic oscillatory mechanism of globus pallidus neurons. Our modeling results suggest a mechanism of action of deep brain stimulation and a pathophysiology of Parkinsonism in which synchrony, rather than firing rate, is the critical pathological feature.

Substantia nigra pars compacta (SNpc) dopaminergic neurons receive strong tonic inputs from GABAergic neurons in the substantia nigra pars reticulata (SNpr) and globus pallidus (GP), and glutamatergic neurons in the subthalamic nucleus. The presence of these tonic inputs raises the possibility that phasic disinhibition may trigger phasic bursts in dopaminergic neurons. We first applied constant NMDA and GABAA conductances onto a two-compartment single cell model of the dopaminergic neuron (Kuznetsov et al., 2006). The model exhibited disinhibition bursting upon stepwise removal of inhibition. A further bifurcation analysis suggests that disinhibition may be more robust than excitation alone in that for most levels of NMDA conductance, the cell remains capable of bursting even after a complete removal of inhibition, whereas too much excitatory input will drive the cell into depolarization block. To investigate the network dynamics of disinhibition, we used a modified version of an integrate-and-fire based model of the basal ganglia (Humphries et al., 2006). Synaptic activity generated in the network was delivered to the two-compartment single cell dopaminergic neuron. Phasic activation of the D1-expressing medium spiny neurons in the striatum (D1STR) produced disinhibition bursts in dopaminergic neurons through the direct pathway (D1STR to SNpr to SNpc). Anatomical studies have shown that D1STR neurons have collaterals that terminate in GP. Adding these collaterals to the model, we found that striatal activation increased the intra-burst firing frequency of the disinhibition burst as the weight of this connection was increased. Our studies suggest that striatal activation is a robust means by which disinhibition bursts can be generated by SNpc dopaminergic neurons, and that recruitment of the indirect pathway via collaterals may enhance disinhibition bursting.

Charles Reagan Wilson considers connections between three sites of racial reconciliation work.

This essay investigates how a strong sense of French heritage has affected the development of the South Louisiana region. It provides an overview of "Cajun" culture, both in terms of its historical origins and its contemporary vestiges. The essay emphasizes such topics as class struggles, religious practices, artistic developments, industry, agriculture, and politics in south Louisiana.

This guide investigates how "the South" has been an ideological and experiential focus for the development of distinctive religious forms and how some of the forms of religion identified with the South—evangelicalism, fundamentalism, pentecostalism—have dispersed throughout the nation.

Increasing copper levels in 120 growing beef heifers, ages 6 to 9 months, was attempted with copper injections and with oral administration of cupric-oxide needles. The weaned Hereford heifers were randomly allocated to three groups, including one with no supplementation. Study results indicate that oral administration of copper-wire particles was effective, cheap, safe and convenient in preventing or treating copper deficiency. Such a deficiency can retard growth in cattle.