Structure determination of the clean Co(110) surface by LEED

The atomic structure of the (11 0) surface of cobalt has been determined by LEED using six intensity spectra at normal incidence. The surface exhibits the truncated bulk structure with a contraction of the first interlayer spacing by about 8.5% with respect to the bulk value. Quantitative evaluation of the LEED spectra was done using Zanazzi and Jona's and Pendry's r-factors. The minimum averaged r-factors are and . No change of the interatomic distances within the plane could be detected and no rearrangement of the surface structure takes place up to temperatures shortly below the transition temperature

The Bellman's tale - Part 2

Michael Berning was a member of the Rhodes University Library staff from 1965 until his retirement in 1997. He was Tower Captain of the Grahamstown Cathedral during the 1980s

United Albany Brethren Benefit Society

The United Albany Brethren Benefit Society (Albany Brethren) was a Grahamstown example of the friendly society movement which reached a peak in Britain during the last century

The Cultural Television Channel Arte and the (Non-)existence of a Cross-border Franco

Résumé : English (or French) Title : « La chaîne culturelle Arte et la (non) existence d'un espace public franco-allemand » Abstract

Modus operandi as technique in suspect identification in burglary cases

The research attempts to establish how modus operandi can be used to identify suspects in burglary cases. To conduct effective investigation, it is important for investigators to be familiar with the concept modus operandi, its elements, its influence and its values. To achieve the goals and objectives of the practice of modus operandi, investigators must know how to apply modus operandi, what the situational factors are during a criminal act, and how to use it as technique to identify suspects in burglary cases. The direction by implication and clarification of the crime situation is hardly possible without the determination of the identity of the perpetrator or suspect of a criminal act. The recognition of the modus operandi system as any form of evidence gathering is of outmost importance.Criminology and Security ScienceM.Tech. (Forensic investigation

The Effects of Functional Fatigue on Ground Reaction Forces of a Jump, Land, and Cut Task

Rapid acceleration, deceleration, landing and change of direction have been implicated as mechanisms of noncontact anterior cruciate ligament (ACL) injury. PURPOSE: To examine the ground reaction forces occurring to the knee during non-fatigued and fatigued jump, land and cut maneuvers in three unplanned cutting directions. METHODS: Eleven healthy, adult female collegiate soccer athletes participated in this study (age= 20.3±0.9 years; height= 167.4±4.8 cm; mass= 63.7±7.7 kg). Each subject was instructed to perform 9 jump, land, and cut maneuvers in a pre-fatigued state and fatigued state. The protocols were randomly assigned to include 3 cuts in each of the three directions. The functional fatigue protocol consisted of rapid acceleration, deceleration, and change of direction activities. A 2x2 ANOVA design was used to compare groups (fatigue state) and (leg dominance). RESULTS: Differences were noted in the medial direction during the left cut land (p=0.049). Differences in the anterior-posterior forces occurred during fatigued landing tasks for all three cutting directions (left, p=0.049; center, p=0.000; right, p=0.009), and for the center cut push off (p=0.020). Fatigue appeared to have a significant impact on the vertical push off of all three directions (left, p=0.023; center, p=0.000; right, p=0.047). CONCLUSION: Fatigue has an important impact on jump, land and cut maneuvers regardless of cutting direction. Fatigue was noted to impact the anterior-posterior direction the most during landing which is significant as the primary purpose of the ACL is to prevent anterior shear force of the tibia on the femur during motion. Fatigue may prove to be a predominant risk factor for ACL injuries

A COMPARISON OF RESISTED AND ASSISTED SPRINT TRAINING IN COLLEGIATE SPRINTERS

Sprint time (ST) is the product of stride length (SL) and stride rate (SR). Increases in either of these variables results in speed improvement. Purpose:  To compare resisted (RST) and assisted sprint training (AST) on sprint performance. Methods:  Twenty (10 male, 10 female) collegiate sprinters and hurdlers were randomly divided into two training groups: RST (age: 21.8±1.8yrs, height: 1.73±0.10m, mass: 69.5±12.8kg) and AST (age: 22.2±2.4yrs, height: 1.76±0.10m, mass: 69.1±9.9kg). Each group trained 3 days/week for 6 weeks. The RST group used a combination of weighted sled pulls, uphill sprinting and depth jumps. The AST group combined downhill running, towing, sprint ladders and single leg bounds. Prior to and following the training interventions SL and ST (10 meter sprint time) were recorded at sprint distances of 30m, 60m, and 120m during the last 10 meters of each sprint distance. Pre-post training ST and SL were compared within training groups at each sprint distance using paired t-tests. Additionally, a gain score was calculated by taking the difference between the post and pre test scores. The gain scores for SL and ST were compared between training groups via independent t-tests at each sprint distance. Results: For the RST 30m, ST (1.18±0.08s vs 1.14±0.08s, p<0.01) and SL (2.06±0.08m vs. 2.09±1.14m, p<0.01) were significantly improved. For the AST, 30m ST (1.19±0.08s vs. 1.18±0.08s, p<0.01) and SL (2.10±0.13m vs. 2.11±0.13, p=0.04) were significantly improved. No improvements in ST or SL were detected for either the RST or AST groups at the 60m sprint distance. For the RST 120m, ST (1.13±0.07s vs. 1.12±0.08s, p<0.01) was significantly improved. For the AST 120m, ST (1.12±0.07s vs. 1.11±0.07s, p<0.01) and SL (2.30±0.08 vs. 2.33±0.08, p<0.01) were significantly improved. At the 30M interval, the RST demonstrated significant improvements in SL and ST as compared to the AST (p<0.01). However, at the 120M interval, the AST demonstrated a significant improvement in SL as compared to the RST (p<0.01). Conclusion: Within the parameters of this study, RST and AST methods have proven effective at improving sprint performance. It appears that RST protocols may be of greatest benefit for improving sprint performance at shorter distances, while AST protocols may be of greater benefit at longer sprinting distances.  Article visualizations

EFFECT OF WEIGHTED JUMP WARM-UP ON VERTICAL JUMP IN FEMALE VOLLEYBALL PLAYERS

Warm-ups which elicit a post activation potentiation (PAP) effect may increase performance in subsequent activities requiring strength and power. However, finding practical methods to best manipulate and exploit PAP remains elusive. Purpose: To determine if a warm-up that included weighted jumps would elicit a PAP effect and increase subsequent vertical jump (VJ) height. Methods: Ten female NCAA Division II volleyball players participated (age = 19.8 ± 1.8 yrs; mass = 71.7 ± 9.7 kg; ht = 167.8 ±23.9 cm). Two warm-up conditions were randomly employed: 1) light jogging, high knees, carioca, shuffling, ankle pops, pogos, and tuck jumps; and 2) an identical warm-up, plus 10 maximal VJs while wearing 20% of bodyweight. At 4-minutes post, VJ was randomly assessed in two conditions: 1) 2-hand standing block VJ (SBVJ), and 2) 1-hand 3-step approach VJ (AVJ). Paired Samples T-test determined if there was a significant difference (p < 0.05) in VJ height between the two conditions. Results: Results were mixed. No significant difference (p > 0.05) occurred in the SBVJ (262.1 vs. 263.0 cm, warm-up vs. warm-up with weight vest, respectively). However, the AVJ was significantly higher by 2.7±1.5 cm (p < 0.05; 275.1±13.2 vs. 277.8±13.2 cm) with the weight vest added to their warm-up. Conclusion: This study demonstrates that a dynamic warm-up with the addition of weighted jumps may increase 3-step AVJ ability in female collegiate volleyball players. However, no effect was seen in 2-hand SBVJ ability. Coaches may consider using a warm-up that includes weighted jumps to optimize performance in sports like volleyball where vertical jumps with an approach are key components of competition.  Article visualizations