The ventral hippocampus (vHPC), medial prefrontal cortex (mPFC), and basolateral amygdala (BLA) are each required for the expression of anxiety-like behavior. Yet the role of each individual element of the circuit is unclear. The projection from the vHPC to the mPFC has been implicated in anxiety-related neural synchrony and spatial representations of aversion. The role of this projection was examined using multi-site neural recordings combined with optogenetic terminal inhibition. Inhibition of vHPC input to the mPFC disrupted anxiety and mPFC representations of aversion, and reduced theta synchrony in a pathway-, frequency- and task-specific manner. Moreover, bilateral, but not unilateral, inhibition altered physiological correlates of anxiety in the BLA, mimicking a safety-like state. These results reveal a specific role for the vHPC-mPFC projection in anxiety-related behavior and the spatial representation of aversive information within the mPFC. Moreover, these data suggested that theta-frequency input from the vHPC plays a causal role in anxiety-like behavior. Next, it was investigated whether optogenetic stimulation of the vHPC-mPFC at a theta frequency was sufficient to increase anxiety. Stimulating the vHPC input to the mPFC with a sinusoidal light pattern at 8 Hz significantly increased anxiety behavior. The anxiogenic effect of vHPC terminal stimulation was frequency- (8 Hz but not 20 Hz) and pattern- (sinusoids but not pulses) specific. To understand how pulses and sinusoidal light modulate mPFC neurons differentially, mPFC pyramidal neurons were recorded both in vitro and in vivo while stimulating vHPC terminals with the same sinusoidal or pulsatile patterns. In vitro, sinusoidal stimulation increased the rate of spontaneous EPSCs, while pulses evoked strong, stimulus-locked EPSCs. In vivo, sinusoidal stimulation of vHPC terminals increased the phase-locking of mPFC single unit spiking to the optical stimulation pattern without changing overall firing rates. Together, these results suggest that sinusoidal stimulation at 8 Hz enhances theta-frequency activity in mPFC neurons as well as anxiety-related behavior. Moreover, they suggest that theta-frequency components of neural activity play a privileged role in vHPC-mPFC communication and hippocampal-dependent forms of anxiety.

Obesity occurs when nutrient intake exceeds energy expenditure over prolonged periods. In the modern world, obesity has reached epidemic proportions. Complications of obesity, including cardiovascular disease, non-alcoholic fatty liver disease, certain forms of cancer, and metabolic dysfunction contribute substantially to morbidity and death today. With 13% of the world’s population affected, the rising rates of obesity will grow as a public health burden. Until recently, pharmacologic attempts to treat obesity have focused on reducing food intake. However, motivated in part by recent studies in mice and by analyses of fat in humans, approaches to increasing energy expenditure, specifically thermogenic energy expenditure, may provide a new therapeutic avenue. Most simplistically, there are two classes of adipocytes: storage and thermogenic. Storage fat, typically composed of unilocular white adipocytes function as storage depots for excess calories. On the other hand, thermogenic fat containing brown or beige adipocytes, generate heat through uncoupled mitochondrial respiration, This regulated generation of heat, known as thermogenesis, is used by organisms to maintain or increase body temperature. Historically, thermogenesis has been divided into shivering and nonshivering thermogenesis. Repeated, rapid contraction of skeletal muscles generate heat and is the basis for shivering thermogenesis. Nonshivering thermogenesis (NST) describes all the other mechanisms by which an organism can generate regulated heat. Only two organelles are known to contribute to NST: the mitochondrion of brown and beige adipocytes and the sarcoplasmic reticulum of muscle. The role of other organelles has not been systematically studied. Here we show in mice that thermogenic stimuli, including a cold challenge and pyrogenic molecules, activate a lysosomal program in a known thermogenic tissue (BAT) as well as several “non-thermogenic” organs, including the spleen, liver and skeletal muscle. A similar program is activated by a cold challenge in the metazoan, Drosophila melanogaster, suggesting an evolutionarily ancient origin for this response. We show by both pharmacologic and genetic means that impairment of lysosomal function compromises the thermogenic response of individual cells ex vivo and of mice in vivo. Data from genetic manipulations find that impairment of lysosome function that leads to cold intolerance and death can modestly downregulate the classical Ucp1 thermogenic program. However, pharmacological inhibition reveals that impairment of lysosome function can compromise thermogenesis without altering the Ucp1 program. As part of our efforts to study lysosome function in thermogenesis we developed a new method of measuring thermogenesis in primary cells. Using isothermal titration calorimetry (ITC), we quantitatively measured the heat generated by cells isolated from mice. This permitted us to assess the effects of both genetic and pharmacologic manipulations on the generation of heat and allowed us, for the first time, to measure the heat (uCal/sec/cell) of BAT in the basal and stimulated state. With ITC, we demonstrated that the impairment of lysosome function had direct effects on the generation of cellular heat, independent of systemic modulators of temperature such as basal metabolic rate or circulatory dissipation. From these studies, we conclude that lysosomes are thermogenic organelles induced by cold and pyrogenic stimuli and contribute both directly and indirectly to thermogenesis. Our work also suggests that lysosome thermogenesis may provide a means of thermoregulation in non-homeotherms as well as in tissues previously not implicated in temperature regulation in mammals.

Introduction: In the US, Black/African Americans comprise the largest proportion of People Living with HIV (PLWH). Depressive symptoms and fatigue are highly prevalent among PLWH. Depressive symptoms are linked to progression of HIV disease, and fatigue is linked to severity of depressive symptoms. Resistance exercise is known to have psychological benefits in non-HIV depressed populations, and these benefits are hypothesized to be intensity-dependent. That is, moderate intensity exercise seems to stimulate better psychological outcomes compared to other exercise intensities. To date, no study has examined the acute psychological effects of resistance exercise intensity with depressed PLWH. Purpose: To test the acute effects of resistance exercise intensity on affect, perceived activation, and perceived distress among sedentary Black/African American PLWH who experience depressive symptoms. Methods: Twenty-five men and 17 women ages 24-66 (47.5±11.2) with a Center for Epidemiologic Studies Depression Scale score of ≥10 completed a battery of questionnaires and 10-repetition maximum (10-RM) muscular strength tests. Participants were randomized into a moderate intensity resistance exercise group (i.e., 70% of 10-RM), n=21, or vigorous intensity resistance exercise group (i.e., 100% of 10-RM), n=21. Both groups completed 3 sets of 10 repetitions for 5 exercises at the assigned intensity. Exercises include squat, chest press, lat pull-down, dumbbell shoulder press, and dumbbell biceps curl. Affect, perceived activation, and perceived distress were measured with the Feeling Scale, Felt Arousal Scale, and Subjective Units of Distress Scale, respectively. Measures were administered at PRE, MID, POST, at 15-minute DELAY, and at 30-minute DELAY. Changes were analyzed using repeated measures ANOVA, with Bonferroni adjustments for post-hoc analyses. Results: There were significant Time x Group interactions for affect (F=2.6, p=0.03, η2=0.1), and perceived distress (F=5.5, p<0.01, η2=0.1), and a main effect of Time for perceived activation (F=16.2, p<0.001, η2=0.3). In the moderate intensity group, affect improved PRE to POST (t=3.2, p<0.01, d=0.7), PRE to DELAY 15 (t=4.1, p<0.01, d=0.9), and PRE to DELAY 30 (t=4.1, p<0.001, d=0.7). In addition, perceived distress was reduced from PRE to MID (t=4.2, p<0.001, d=0.9), PRE to POST (t=5.5, p<0.001, d=1.2), PRE to DELAY 15 (t=5.6, p<0.001, d=1.2), and PRE to DELAY 30 (t=6.7, p<0.001, d=1.5). In the vigorous intensity group, affect declined PRE to MID (t=2.9, p<0.01, d=-0.6), while perceived distress improved PRE to DELAY 15 (t=4.8, p<0.001, d=1.0) and PRE to DELAY 30 (t=3.5, p<0.01, d=0.7). Perceived activation increased in both groups similarly PRE to MID (t=5.1, p<0.01, d=1.5), and PRE to POST (t=6.1, p<0.001, d=1.8). Conclusions: Results suggest that an acute bout of moderate intensity resistance exercise is more effective than vigorous intensity resistance exercise in improving affect, increasing energy, and reducing distress in depressed Black/African American PLWH. However, vigorous intensity resistance exercise also appears to have distress-reducing benefits, but this appears to only occur after exercise. These findings should be considered when prescribing exercise for depressive symptom management in this population.

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Chan Oi Wan = 運動前進食不同血糖指數食物及運動中補充碳水化合物飲料對長跑能力的影響 / 陳靄允. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 72-91). / Text in English; abstracts in English and Chinese. / Chan Oi Wan = Yun dong qian jin shi bu tong xue tang zhi shu shi wu ji yun dong zhong bu chong tan shui hua he wu yin liao dui chang pao neng li de ying xiang / Chen Aiyun. / Acknowledgments --- p.i / Abstract --- p.iii / Table of Contents --- p.vii / List of Figures --- p.ix / List of Tables --- p.x / Chapter Chapter One --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Purpose --- p.5 / Chapter 1.3 --- Significance of the Study --- p.5 / Chapter Chapter Two --- Review of Literature --- p.6 6 / Chapter 2.1 --- "Energy Metabolism during Prolonged, Submaximal Exercise" --- p.6 / Chapter 2.2 --- Importance of Nutrition on Exercise Performance --- p.9 / Chapter 2.3 --- Application of GI --- p.20 / Chapter CHAPTER Three --- Methodology --- p.36 / Chapter 3.1 --- General Methods --- p.36 / Chapter 3.2 --- Preliminary Testing --- p.42 / Chapter 3.3 --- Subjects --- p.45 / Chapter 3.4 --- Experimental Design --- p.46 / Chapter 3.5 --- Procedures --- p.47 / Chapter 3.6 --- Prescribed Meals --- p.50 / Chapter 3.7 --- Prescribed CHO-electrolyte Drink --- p.50 / Chapter 3.8 --- Statistical Analysis --- p.51 / Chapter Chapter Four --- Results --- p.52 / Chapter 4.1 --- Dietary Analysis --- p.52 / Chapter 4.2 --- Running Performance --- p.52 / Chapter 4.3 --- Blood Metabolites --- p.53 / Chapter 4.4 --- Metabolic Responses --- p.60 / Chapter 4.5 --- Subjective Responses and Heart Rates Responses --- p.61 / Chapter Chapter Five --- Discussion --- p.64 / Recommendations and Applications --- p.70 / References --- p.72 / Appendices --- p.95

Neural representations of odors get associated with other stimuli through experience. Are action potentials the neural representation that directly gets associated with reinforcement during conditioning? In Manduca , I found that odor presentations elicited only one or two spikes at odor onset (and sometimes offset) in each of a small portion of Kenyon cells, a population of neurons known to be crucial for olfactory associative learning. By using a series of odor-taste associative conditioning paradigms with various sucrose presentation timings, I carefully controlled the temporal overlap between Kenyon cell spiking and sucrose reinforcement timing. I found that in paradigms that led to learning, spiking in Kenyon cells ended well before the reinforcement was given. Further, increasing the temporal overlap between Kenyon cell spiking and sucrose reinforcement actually reduced learning efficacy. Therefore, spikes in Kenyon cells are not the neural representation that gets directly reinforced, and Hebbian spike timing--dependent plasticity in Kenyon cells alone cannot underlie this learning. / Two important focuses in neuroscience are to study how animals process sensory stimuli, and how such stimuli get associated with other sensory modalities through experience. Often, sensory stimuli elicit the oscillatory synchronization of neurons in different parts of the brain, and thus may constitute an important stage in sensory processing. Odor-evoked oscillatory synchronization has been observed in a wide variety of animals, including mammals and insects. Despite differences in details of anatomical structure, animals from widely different phyla appear to use similar strategies to encode odors. Here, using the moth Manduca sexta, I examined the factors that cause odor-evoked oscillatory synchronization of olfactory neurons and that determine the frequency of these oscillations. I found that frequency of oscillations decreased from &sim;40 Hz to &sim;20 Hz during the course of a lengthy odor pulse. This decrease in oscillatory frequency appeared in parallel with a decrease in net olfactory receptor output, suggesting that the intensity of olfactory receptor neuron input to the antennal lobe, the first olfactory relay center, may determine oscillatory frequency. However, I found that changing odor concentration had little effect on oscillatory frequency. Combining the results of recordings made in vivo and computational models, I found that increasing odor concentration recruited additional, but less well-tuned olfactory receptor neurons to respond to the odor. Firing rates of these neurons were tightly constrained by adaptation and saturation. My work established that, in the periphery, odor concentration is mainly encoded by the size of the olfactory receptor neuron population that responded to the odor, whereas oscillatory frequency is determined by the adaptation and saturation of this response. / Ong, Chik Ying Rose. / Advisers: Siu Kai Kong; Mark Stopfer. / Source: Dissertation Abstracts International, Volume: 72-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 132-147). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Wu Yan. / "August 2003." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (p. 141-170). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

The ability to selectively attend to aspects of the environment which signal opportunity or danger, while marginalising irrelevant stimuli is critical to an animal's survival. With finite cognitive resources, the brain must dedicate resources to only those stimuli that are biologically significant. Incoming thalamic information must therefore be filtered. The thalamic reticular nucleus has long been considered critically involved in modulating thalamic sensory processing. Sharing connections with both the thalamus and cortex, it is ideally located to modulate the transfer of pertinent incoming sensory information. This thesis sought to determine the functional role of the thalamic reticular nucleus in attentional processes by combining lesion techniques and well established behavioural paradigms. Chapter 3 examined the role of visual thalamic reticular nucleus lesions on performance in a two-alternative forced choice reaction time task when auditory distractors were presented. No effect of the lesion was found. Chapter 4 examined excitotoxic lesions of thalamic retlcular nucleus on performance in the 7-stage attentional set shifting task. No effect of lesion on performance was found. Chapter 5 examined mediodorsal thalamus and rostral thalamic reticular nucleus lesions on performance in the attentional set shifting task. Despite strong connectivity with prefrontal regions known to be involved in this task, there was no effect of either lesion. Finally, chapter 6 examined the effects of reducing dopamine input into the thalamic reticular nucleus on a two alternative forced choice reaction time task. Following bilateral lesions the animals were impaired in the re-orientation of attention – suggesting a critical role for both the thalamic reticular nucleus and dopamine in attentional processes. Taken together, these results suggest that while the thalamic reticular nucleus is involved in attention, it is not involved in every aspect.

This thesis explores the recent phenomenon of music concert goers filming these concerts and uploading the footage to YouTube. This contemporary practice poses several questions of the nature of contemporary music culture. The status of the concert as live event is problematised by this mediation of the experience. The videos create producers of fans and allow these fans to make a substantive contribution to music culture as authors of music texts consumed through a major distribution network. The fact that these fans are not paid for their efforts begs the question as to what they gain from this enterprise; particularly as it serves as a distraction for filmers from the immersive concert experience. This thesis will use the work of Walter Benjamin on the ‘aura' as a yardstick against which to judge current attitudes amongst music fans as to the status of live music alongside other ways of experiencing music. The thesis will also offer a contemporary reappraisal of Pierre Bourdieu's concept of ‘cultural capital' that accounts for the recognition that filmers receive from other music fans for their efforts in filming concerts. Concerts are restricted spaces in which music is simultaneously produced and consumed. Broadcasting videos of these events on YouTube provides recognition for filmers both for having attended and managed to capture footage to be shared with those unable to attend for various reasons. Filmers are not paid for their efforts and so this recognition serves as a form of cultural capital in lieu of financial reward. The thesis is based upon interviews with a global sample of music fans who either film concerts or watch these films on YouTube.

This study investigated whether or not a relationship exists between ventilation and oxygen uptake at 40% and 85% of V02 peak intensity in 30 upper body fit and 30 unfit 18- 35-year-old women. The correlations between ventilation and oxygen uptake at 40% of peak intensity for the fit group (r = -.51) and the unfit group (r = -.48) were modestly negative. At 85% intensity the relationship between ventilation and oxygen uptake in the two groups was -.44 and -.66, respectively. The lower correlations between ventilation and oxygen uptake observed at the 85% level of peak intensity among the unfit group could be due to a lower ventilatory threshold (66% = fit; 49% = unfit), lesser local muscle changes, along with reduced lactate and C02 management; all of which would be improved with training.