'There is no heritage in Qatar': Orientalism, colonialism and other problematic histories

This article discusses the construction of Qatari heritage in the context of pre-conceived ideas of ‘cultural heritage’ predominant in the global and regional spheres that operate in this country. It considers the location of Qatar within Middle Eastern heritage discourses and debates, and identifies productive similarities as well as unique avenues for further discussion. The authors identify the challenge of formulating methodologies that are able to recognize, accommodate, encompass and reflect local heritage dialogues and practices that exist in Qatar, which may aid in further researching the wider Arabian Peninsula, its histories and heritages

Functional phases and angular momentum characteristics of Tkatchev and Kovacs

Understanding the technical requirements and underlying biomechanics of complex release and re-grasp skills on high bar allows coaches and scientists to develop safe and effective training programmes. The aim of this study was to examine the differences in the functional phases between the Tkatchev and Kovacs skills and to explain how the angular momentum demands are addressed. Images of 18 gymnasts performing 10 Tkatchevs and 8 Kovacs at the Olympic Games were recorded (50 Hz), digitised and reconstructed (3D Direct Linear Transformation). Orientation of the functional phase action, defined by the rapid flexion to extension of the shoulders and extension to flexion of the hips as the performer passed through the lower vertical, along with shoulder and hip angular kinematics, angular momentum and key release parameters (body angle, mass centre velocity and angular momentum about the mass centre and bar) were compared between skills. Expected differences in the release parameters of angle, angular momentum and velocity were observed and the specific mechanical requirement of each skill were highlighted. Whilst there were no differences in joint kinematics, hip and shoulder functional phase were significantly earlier in the circle for the Tkatchev. These findings highlight the importance of the orientation of the functional phase in the preceding giant swing and provide coaches with further understanding of the critical timing in this key phase

Biomechanical evolution of the Tkachev on uneven bars in female gymnastics

The development of joint kinematics and kinetics is fundamental to the successful performance of complex flight skills in gymnastics bar routines. Biomechanical understanding of these skills can provide coaches and scientists with key information to make training safe and effective. The Tkachev is a complex and popular gymnastics skill with many different variations. Recently, a new version has been performed, which has become popular with elite female performers. This study examined the key biomechanical characteristics of this skill and contrasted these to the earlier versions reported. Elite female gymnasts (n = 5) were recorded and manually digitised using twin video cameras (50 Hz) at the 2007 World Gymnastics Championships. Three-dimensional (3D) DLT was used to reconstruct the real world coordinates. Individualised inertia characteristics were calculated and used to determine mass centre kinematics. Inverse dynamics analysis was used to calculate joint kinetics at the hips and shoulders from the known values at the toes. The results of this study showed an increased flight time and rotational capacity during the aerial phase for the toe-on Tkachev, as well as a more simple movement pattern and joint kinetic demand with single power impulses at the hips and shoulders compared with previous versions. The key finding of this study was that the toe-on version appeared to be less physically demanding than that the inward and outward techniques, and provide the opportunity to perform more complex aerial phase body positions. These results can help coaches to physically prepare their gymnasts and biomechanists in terms of understanding the demands of these skills

Regional Conformational Flexibility Couples Substrate Specificity and Scissile Phosphate Diester Selectivity in Human Flap Endonuclease 1

Human flap endonuclease-1 (hFEN1) catalyzes the divalent metal ion-dependent removal of single-stranded DNA protrusions known as flaps during DNA replication and repair. Substrate selectivity involves passage of the 5′-terminus/flap through the arch and recognition of a single nucleotide 3′-flap by the α2–α3 loop. Using NMR spectroscopy, we show that the solution conformation of free and DNA-bound hFEN1 are consistent with crystal structures; however, parts of the arch region and α2–α3 loop are disordered without substrate. Disorder within the arch explains how 5′-flaps can pass under it. NMR and single-molecule FRET data show a shift in the conformational ensemble in the arch and loop region upon addition of DNA. Furthermore, the addition of divalent metal ions to the active site of the hFEN1–DNA substrate complex demonstrates that active site changes are propagated via DNA-mediated allostery to regions key to substrate differentiation. The hFEN1–DNA complex also shows evidence of millisecond timescale motions in the arch region that may be required for DNA to enter the active site. Thus, hFEN1 regional conformational flexibility spanning a range of dynamic timescales is crucial to reach the catalytically relevant ensemble

A social and historical interpretation of Ramesside period votive stelae

The following thesis analyses a dataset of 436 Egyptian votive stelae dating to the Ramesside period (1295-1069 ВСЕ), from six sites: Deir el Medina at Thebes (264 stelae), non-Deir el Medina stelae (55) from the Theban area, Abu Simbel (21 stelae) and Wadi es-Sebua (15 stelae) in Lower Nubia, Qantir/Pi-Ramesses in the eastern Delta (74 stelae) and Zawiyet Umm el-Rakham (7 stelae) in the Libyan desert. The stelae were drawn from published catalogues of museum collections, excavation reports, individual publications, and photographs supplied by institutions and researchers where no published image existed. The thesis presents the votive stelae as the end result of defined social practices, exploring the role of votive stelae as social artifacts which, through image, text and materiality, are active agents in transmitting information on individual and group social status and identity, normative social structure, and alternate social organisation. The stelae are analysed according to the iconographie content, status- or function-related information (title and/or clothing of the dedicator), and original location, or context, of the stela. These elements are understood to provide information on the social context for the utilisation of stelae in Ramesside Egypt. Central to the thesis is a reading of the representations as coded references to actual events, or practices. The examination requires an analysis of the social and representational conventions within which the stelae and their representations were created. The methodology is initially tested against the core dataset of Deir el Medina stelae, followed by a comparative analysis of the non-Deir el Medina stelae from Thebes, and the remaining four geographically distant sites. The thesis reveals the form, use and production of votive stelae are related to royal activity and sanctions, and promulgate the shifting central ideology and structure. The votive stelae can also, when the iconography is decoded, be linked to specific events, illuminating the local social milieu of the communities studied, and their internal social organisation

The cross on rings performed by an Olympic champion

The cross is a key skill in Male Artistic Gymnastics rings routines. However, few researches were found about this skill. There is knowledge about the forces needed to perform the cross, or about muscles activation, separately. The aim of this paper was to accomplish a comprehensive research about the biomechanics of cross on rings, in order to obtain a descriptive model about this skill. Therefore, the currently Olympic champion on rings event volunteered in this research. He performed three crosses with the usual apparatus in his training gym. The measurement methods were combined: One digital video camera, one strain gauge in each cable and surface electromyography of nine right shoulder muscles were used. Statistical analyses were performed by parametric and non parametric tests and descriptive statistics. Symmetry values were calculated for shoulder angles and cables of right and left side. Coefficient of variation of muscle activation and co contraction were verified. Within gymnast variability was calculated using biological coefficient of variation (BCV), discretely for kinematic measures. Low variability values of shoulder angles and cable forces were verified and low values of asymmetry as well. Muscle activation varied according to muscle function, while co-contraction values were different among trials. These results pointed out the characteristics of the cross performed by an elite gymnast. Knowledge about the characteristics of cross can inform coaches, practitioners and clinicians how a successful skill should be presented

SPECIFIC-OVERLOAD CHARACTERISTICS OF HORIZONTAL JUMP EXERCISES IN COMPARISON TO THE BLOCK START

The aim of this study was to compare kinetic data at the ankle, knee and hip joint between the block start and three variations of horizontal jump exercises. Eight male sprinters (100 m PB 10.88 ± 0.18 s) performed each exercise whilst external force (1000 Hz) and 3D kinematics (250 Hz) were collected. Internal kinetics at the ankle, knee and hip joint were calculated using inverse dynamics. Key results indicated significantly increased moment and power at the ankle joint in the horizontal jumps compared with the block start, but no differences in power at the knee and hip joint. The present study highlighted specific-overload at the ankle joint but also similarity in the organisation of power across all joints. The information provides coaches and athletes with key biomechanical information to inform exercise selection for physical preparation programmes

Asymmetry analysis of the arm segments during forward handspring on floor

Asymmetry in gymnastics underpins successful performance and may also have implications as an injury mechanism; therefore, understanding of this concept could be useful for coaches and clinicians. The aim of this study was to examine kinematic and external kinetic asymmetry of the arm segments during the contact phase of a fundamental skill, the forward handspring on floor. Using a repeated single subject design six female National elite gymnasts (age: 19 ± 1.5 years, mass: 58.64 ± 3.72 kg, height: 1.62 ± 0.41 m), each performed 15 forward handsprings, synchronised 3D kinematic and kinetic data were collected. Asymmetry between the lead and non-lead side arms was quantified during each trial. Significant kinetic asymmetry was observed for all gymnasts (p < 0.005) with the direction of the asymmetry being related to the lead leg. All gymnasts displayed kinetic asymmetry for ground reaction force. Kinematic asymmetry was present for more gymnasts at the shoulder than the distal joints. These findings provide useful information for coaching gymnastics skills, which may subjectively appear to be symmetrical. The observed asymmetry has both performance and injury implications

GENDER DIFFERENCES AND LOWER LIMB ASYMMETRY IMPLICATIONS DURING DROP LANDINGS

The aim of this study was to investigate asymmetry differences in landing techniques adopted by male and female athletes. Eight (4 male; 4 female) participants (age: 20.5 ±0.7 years, mass: 73.09 ±12.05 kg, height: 1.77 ±0.75 m performed drop landings from two heights (0.60 m & 0.90 m). Kinematic and kinetic data were collected during landing and used to calculated asymmetry for joint angles and kinetic variables. Significant (