Beneficial effects of exercise: shifting the focus from body weight to other markers of health

Background: Exercise is widely promoted as a method of weight management, while the other health benefits are often ignored. The purpose of this study was to examine whether exercise-induced improvements in health are influenced by changes in body weight. Methods: Fifty-eight sedentary overweight/obese men and women (BMI 31.8 (SD 4.5) kg/m2) participated in a 12-week supervised aerobic exercise intervention (70% heart rate max, five times a week, 500 kcal per session). Body composition, anthropometric parameters, aerobic capacity, blood pressure and acute psychological response to exercise were measured at weeks 0 and 12. Results: The mean reduction in body weight was −3.3 (3.63) kg (p<0.01). However, 26 of the 58 participants failed to attain the predicted weight loss estimated from individuals’ exercise-induced energy expenditure. Their mean weight loss was only −0.9 (1.8) kg (p<0.01). Despite attaining a lower-than-predicted weight reduction, these individuals experienced significant increases in aerobic capacity (6.3 (6.0) ml/kg/min; p<0.01), and a decreased systolic (−6.00 (11.5) mm Hg; p<0.05) and diastolic blood pressure (−3.9 (5.8) mm Hg; p<0.01), waist circumference (−3.7 (2.7) cm; p<0.01) and resting heart rate (−4.8 (8.9) bpm, p<0.001). In addition, these individuals experienced an acute exercise-induced increase in positive mood. Conclusions: These data demonstrate that significant and meaningful health benefits can be achieved even in the presence of lower-than-expected exercise-induced weight loss. A less successful reduction in body weight does not undermine the beneficial effects of aerobic exercise. From a public health perspective, exercise should be encouraged and the emphasis on weight loss reduced

Compact, low-threshold femtosecond lasers

This thesis is concerned with the design and development of compact, all-solid-state femtosecond pulse lasers with low pump power requirements. A number of directly-diode- pumped laser systems based on the gain materials Cr3:LiSrGaF6 (chromium-doped lithium strontium aluminium fluoride) and Cr3:LiSrGaF6 (chromium-doped lithium strontium gallium fluoride) pumped with AlGaInP laser diodes are described. The motivation behind this work was the development of portable, low-noise and lower cost ultrashort pulse lasers for a number of low-power applications such as the characterisation of electron-optical streak camera systems. The investigation into the modelocking of lasers with modest intracavity powers was also an important challenge. The achievement of a battery-powered, compact and efficient laser system represents an excellent outcome for this research programme. Major consideration is given to the key factors that determine both the cw and modelocking thresholds of an ultrashort-pulse laser. In particular, the reduction of intracavity optical losses by designing the laser to operate with fewer cavity elements, the optimisation of second-order and higher-order dispersion for efficient modelocked operation and the inclusion of a semiconductor saturable absorber mirror for increased stability are discussed. This has enabled pump thresholds to be reduced to a level permitting, for the first time, the use of diffraction-limited, narrow-stripe laser diodes for efficient, low-power optical pumping. A number of laser oscillators with novel cavity designs and progressively lower pump thresholds are described. Pulses as short as 57 fs and average output powers as high as 9 mW for only 80 mW of incident pump power are reported for a battery powered femtosecond Cr:LiSAF laser. This represents an overall electrical-to-optical conversion efficiency of approximately 1% which is excellent for a femtosecond pulse laser system. In addition, the amplitude and phase noise performance is shown to be exceptionally good and is believed to be the best yet reported for this type of ultrashort pulse laser. The design and demonstration of highly compact, ultrashort-pulse lasers incorporating novel resonator configurations and simplified dispersion compensation schemes are then described. These lasers produced sub-ps pulses at cavity frequencies as high as 450 MHz

Mechanisms responsible for homeostatic appetite control: theoretical advances and practical implications

Introduction: Homeostatic appetite control is part of a psychobiological system that has evolved to maintain an adequate supply of nutrients for growth and maintenance. The system links the physiological needs for energy with the behaviour that satisfies these needs (feeding), and is shaped by excitatory and inhibitory signals. Owing to rapid shifts in the food environment, homeostatic appetite control is not well adapted for modern-day human functioning. Areas covered: Homeostatic appetite control has two divisions. Tonic processes exert stable and enduring influences, with signals arising from bodily tissues and metabolism. Episodic processes fluctuate rapidly and are related to nutrient ingestion and the composition of foods consumed. Research in these areas incorporates potent endocrine signals that can influence behaviour. Expert commentary: The regulation of adipose tissue, and its impact on appetite (energy) homeostasis, has been heavily researched. More recently however, it has been demonstrated that fat-free mass has the potential to act as a tonic driver of food intake. A challenging issue is to determine how the post-prandial action of episodic satiety hormones and gastrointestinal mechanisms can effectively brake the metabolic drive to eat, in order to keep food intake under control and prevent a positive energy balance and fat accumulation

Low Fat Loss Response after Medium-Term Supervised Exercise in Obese Is Associated with Exercise-Induced Increase in Food Reward

Objective. To examine exercise-induced changes in the reward value of food during medium-term supervised exercise in obese individuals. Subjects/Methods. The study was a 12-week supervised exercise intervention prescribed to expend 500 kcal/day, 5 d/week. 34 sedentary obese males and females were identified as responders (R) or non-responders (NR) to the intervention according to changes in body composition relative to measured energy expended during exercise. Food reward (ratings of liking and wanting, and relative preference by forced choice pairs) for an array of food images was assessed before and after an acute exercise bout. Results. 20 responders and 14 non-responders were identified. R lost 5.2 kg ± 2.4 of total fat mass and NR lost 1.7 kg ± 1.4. After acute exercise, liking for all foods increased in NR compared to no change in R. Furthermore, NR showed an increase in wanting and relative preference for high-fat sweet foods. These differences were independent of 12-weeks regular exercise and weight loss. Conclusion. Individuals who showed an immediate post-exercise increase in liking and increased wanting and preference for high-fat sweet foods displayed a smaller reduction in fat mass with exercise. For some individuals, exercise increases the reward value of food and diminishes the impact of exercise on fat loss

Titanium sapphire : A decade of diode-laser pumping

For many years, Ti:sapphire was the prototypical example of a solid-state laser material that could not be diode pumped. The rationale for this assessment follows from the laser properties of Ti:sapphire, which combine to demand high brightness pumping in the blue-green region (see fig. 1 [1]). The development of efficient Gallium Nitride (GaN) based laser diodes eroded this logic [2], and improvements in the spatial brightness of GaN diode lasers subsequently enabled the first demonstration of a directly diode-laser pumped Ti:sapphire laser in 2009 [3], This presentation will outline the physics that makes diode-pumping difficult, and the developments that mean, it is, nonetheless, possible. Interestingly, diode-pumping of CW and modelocked Ti:sapphire lasers was achieved not by a radical redesign of the laser, but by careful optimisation of existing approaches that enabled the rapidly improving brightness of GaN diode lasers to be exploited [3-5]

Ultrafast diode-pumped Ti:sapphire laser with broad tunability

We report a broadly wavelength-tunable femtosecond diode-pumped Ti:sapphire laser, passively mode-locked using both semiconductor saturable absorber mirror (SESAM) and Kerr-lens mode-locking (KLM) techniques. Using two pump laser diodes (operating at 450 nm), an average output power as high as 433 mW is generated during mode-locking with the SESAM. A tunability range of 37 nm (788-825 nm) was achieved with the shortest pulse duration of 62 fs at 812 nm. In the KLM regime, an average output power as high as 382 mW, pulses as short as 54 fs, and a tunability of 120 nm (755-875 nm) are demonstrated

A broadly tunable ultrafast diode-pumped Ti:sapphire laser

We report a diode-pumped ultrafast Ti:sapphire laser tunable over a 50 nm range. Sub-100 fs pulses are generated at a pulse repetition rate of 139 MHz with a maximum average output power of 430 mW

Prospectus, March 13, 1972

ENJOYABLE COURSES OFFERED, EVENING PROGRAM EXPANDS; Popular Enivronment Course Repeated; Program Reports; Household Electronics Offered for Spring Qtr.; Owens Selected As Consultant; Final Examination Schedule; Letters to the Editor; What\u27s Going On; Counselor\u27s Corner: EIU Admissions, EIU Transfers, U of I, Evening Counseling; Parkland Notices: Allied Health Applicants, Parkland Magazine, Pi Sigma Iota, Foreign Language Review, Public Aid, Student Services, Wanted, Directory; WLS Wave Length; Satire: Conversations with the Candidates; Orpheus Reborn: Words from a Shell, Pepare for Death, hunting?, i.e. (fill)..., Times Landscape, ifind...; Journalism Club to Chicago; Little Jimmie; Kevin On Environment; Chester Lewis 1st In State, 8th In Nation; Hart Beat; Track Team Prepares For Upcoming Season; Mock Is Unanimous Conference Pick; Late Item; IM Basketball Standingshttps://spark.parkland.edu/prospectus_1972/1009/thumbnail.jp

Localization and Characterization of Fatigue Cracks Around Fastener Holes Using Spherically Focused Ultrasonic Probes

Results are presented from laboratory experiments and simulations designed to determine the ability to localize and characterize fatigue cracks around fastener holes using spherically fo-cused ultrasonic (UT) probes for shear-wave inspections. In designing and evaluating inspection protocols, the number of cases that can be studied through laboratory experiments is severely limited by cost and time constraints. Simulations therefore stand to play a significant role in the design and optimization of inspection strategies for those conditions that can be accurately mod-eled. Moving from benchmark studies for relatively simple geometries toward more realistic conditions creates significant challenges. For shear-wave inspections of fastener holes these challenges include the complex energy field in the thin plates, reflections off the borehole, the complexity of making measurements in the near-field, material anisotropy, cracks as small as 1mm square, and a sealant layer between aluminum sheets. To achieve comparable modeling and simulation data requires a very accurate experimental setup that allows the probe angle, probe height and scan path to be precisely set. For the modeling, care must be taken to match the applied gain and gates used during acquisition of the experimental data. Initial results presented include sensitivity studies to determine how probe variables (frequency, focal depth, diameter), crack variables (size, shape, location, angle with respect to the probe), and the experimental setup affect results. Simulated and experimental C-scan images for 5 and 10 MHz probes are shown in Figure 1 for a fatigue crack that intersects the back wall. This work is supported by the U.S. Air Force Research Laboratory (AFRL) through Research Initiatives for Materials State Sensing (RIMSS) contract with Universal Technologies Corp., Contract No: FA8650-10-D-5210

A broadly tunable ultrafast diode-pumped Ti:sapphire laser

We report a diode-pumped ultrafast Ti:sapphire laser tunable over a 50 nm range. Sub-100 fs pulses are generated at a pulse repetition rate of 139 MHz with a maximum average output power of 430 mW