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During development cells must change shape and move without disrupting dynamic tissue architecture. This requires robust linkage of cell-cell adherens junctions to the force-generating actomyosin cytoskeleton. Drosophila Canoe and mammalian afadin play key roles in the regulation of such linkages. One central task for the field is defining mechanisms by which upstream inputs from Ras-family GTPases regulate Canoe and afadin. These proteins are unusual in sharing two tandem Ras-association (RA) domains - RA1 and RA2 - which when deleted virtually eliminate Canoe function. Work in vitro has suggested that RA1 and RA2 differ in GTPase affinity, but their individual functions in vivo remain unknown. Combining bioinformatic and biochemical approaches, we find that both RA1 and RA2 bind to active Rap1 with similar affinities, and that their conserved N-terminal extensions enhance binding. We created Drosophila canoe mutants to test RA1 and RA2 function in vivo. Despite their similar affinities for Rap1, RA1 and RA2 play strikingly different roles. Deleting RA1 virtually eliminates Canoe function, whereas mutants lacking RA2 are viable and fertile but have defects in junctional reinforcement in embryos and during pupal eye development. These data significantly expand our understanding of the regulation of adherens junction-cytoskeletal linkages. [ABSTRACT FROM AUTHOR]

Robust linkage between adherens junctions and the actomyosin cytoskeleton allows cells to change shape and move during morphogenesis without tearing tissues apart. The Drosophila multidomain protein Canoe and its mammalian homolog afadin are crucial for this, as in their absence many events of morphogenesis fail. To define the mechanism of action for Canoe, we are taking it apart. Canoe has five folded protein domains and a long intrinsically disordered region. The largest is the Dilute domain, which is shared by Canoe and myosin V. To define the roles of this domain in Canoe, we combined biochemical, genetic and cell biological assays. AlphaFold was used to predict its structure, providing similarities and contrasts with Myosin V. Biochemical data suggested one potential shared function - the ability to dimerize. We generated Canoe mutants with the Dilute domain deleted (CnoADIL). Surprisingly, they were viable and fertile. CnoADIL localized to adherens junctions and was enriched at junctions under tension. However, when its dose was reduced, CnoADIL did not provide fully wild-type function. Furthermore, canoeADIL mutants had defects in the orchestrated cell rearrangements of eye development. This reveals the robustness of junction-cytoskeletal connections during morphogenesis and highlights the power of natural selection to maintain protein structure. [ABSTRACT FROM AUTHOR]

Canoe modality in flatwater canoeing has a clear asymmetrical nature. This study aimed (1) to determine the magnitude and direction of neuromuscular properties, range of motion (ROM) and lower-limb strength asymmetries in female and male canoeists; (2) to establish sex-individualized asymmetry thresholds for canoeists' neuromuscular properties, ROM and lower-limb strength; and (3) to determine the relationship of canoeists' neuromuscular properties, ROM and lower-limb strength asymmetries with a specific canoe–dynamometer performance test. Twenty-one international canoeists were assessed through tensiomyography (TMG), ROM, lower-limb explosive strength, and a specific canoe incremental dynamometric test. The magnitude of asymmetry assessed through TMG and ROM was not modulated either by sex or performance level (international medal vs. non-medal). Females showed greater asymmetry than males on muscle tone of the erector spinae towards non-stroke side (22.75% vs. 9.72%) and the tibialis anterior (30.97% vs. 16.29%), and Fmax in explosive leg press (2.41% vs. 0.63%) towards the stroke side. International medalists showed greater asymmetry in semitendinosus contraction time towards non-stroke side (20.51% vs. 9.43%) and reached Vmax earlier in explosive leg press towards stroke side leg (19.20% vs. 9.40%). A greater asymmetry in Fmax and in Vm, and a smaller asymmetry in Tvmax and in leg press showed a small predictive capacity for canoeists' performance on a specific canoe incremental dynamometry test. Reporting reference data from world-class canoeists' asymmetries can be of great importance for coaches to periodically control lateral asymmetry. [ABSTRACT FROM AUTHOR]

The design and development of product designs is not only carried out in large companies, but can also be carried out by MSME actors. One of the things that can be done is the development of packaging designs. It's the same as in Sapuangin Kopi which is located at the Basecamp hiking trail for Mount Merapi via Klaten, to be precise in Tegalmulyo Village, Kemalang District, Klaten Regency, Central Java. The aim of this research was to obtain the product packaging criteria needed by consumers, create packaging prototypes, and determine the level of consumer satisfaction from the packaging that has been designed. The research method used is Quality Function Deployment (QFD) to look for product packaging criteria needed in the development of packaging designs and create a House Of Quality as a comparison of the criteria that have been selected, then the Kano Model method is used to determine consumer satisfaction with products that have been designed with using Blauth's Formula. From the results of the research conducted, there were 7 criteria out of a total of 8 criteria offered to respondents. The criteria chosen were Practical with a frequency of 90 respondents, Quick Presentation of 59 respondents, Attractive of 61 respondents, Effective of 78 respondents, Quality Maintained of 91 respondents, Affordable of 67 respondents, and Easy to Use attributes of 62 respondents, while from the formulation of the Kano Model it was found that all attributes were included in the Functional category, with the attributes Practical, Quick Presentation, Quality, and Easy to Use included in the one dimensional category. Attractive and Affordable Attributes fall into the attractive category. Then the Effective attribute goes into the must be category. [ABSTRACT FROM AUTHOR]

In 2018, the Cape Porpoise Archaeological Alliance recovered a dugout canoe located during a surface survey of the Cape Porpoise tidal flats in Kennebunkport, Maine. A sample of the canoe dated to between 1275 and 1380 cal AD making it the oldest known from the region. Professional archaeologists and volunteers excavated the canoe from the intertidal in the summer of 2019 for analysis and conservation. This paper provides new insight into pre-Contact watercraft technology in the Far Northeast and emphasizes the promise of citizen science initiatives for identifying and recovering delicate archaeological materials that are exposed and under threat from rapidly changing coastlines. [ABSTRACT FROM AUTHOR]

The oldest canoe discovered in South Carolina was illegally recovered from the Cooper River near Charleston in 1997 and spent 23 years in state custody awaiting funding for conservation treatment. In 2020, it was transferred into the temporary custody of Clemson University's Warren Lasch Conservation Center. Where once the conservation methodology would have begun and ended with an impregnation treatment and vacuum freeze-drying, the Cooper River Canoe Project instead began by consultation with the Native American communities of South Carolina. Through collaboration with Native American leaders, archaeologists, and conservators, the conservation of a 4000-year-old, waterlogged, fragmentary dugout canoe will be undertaken. Unprecedented in South Carolina, the Cooper River Canoe Project challenges established colonial practices in archaeology and conservation, and designs a new approach to the conservation of Native American cultural heritage. By recognizing Native American communities' rights to the management and determination of their cultural heritage, project partners are creating a new model for the conservation of cultural heritage in South Carolina. [ABSTRACT FROM AUTHOR]

Cortical domains are characterized by spatially restricted polarity proteins. The pattern of cortical domains is dynamic and changes during cell differentiation and development. Although there is a good understanding for how the cortical pattern is maintained, e. g. by mutual antagonism, less is known about how the initial pattern is established, and its dynamics coordinated with developmental progression. Here we investigate the initial restriction of subapical marker proteins during the syncytial-cellular transition in Drosophila embryos. The subapical markers Canoe/Afadin, the complex ELMO-Sponge, Baz and Arm become initially restricted between apical and lateral domains during cellularization. We define the role of zygotic genome activation as a timer for subapical domain formation. Subapical markers remained widely spread in embryos treated with α-amanitin and became precociously restricted in mutant embryos with premature zygotic transcription. In contrast, remodeling of the nuclear division cycle without cytokinesis to a full cell cycle is not a prerequisite for subapical domain formation, since we observed timely subapical restriction in embryos undergoing an extra nuclear cycle. We provide evidence that earliest subapical markers ELMO-Sponge and Canoe are required for subapical accumulation of Baz. Supporting an important role of cortical F-actin in subapical restriction, we found that the formin Dia was required for Baz restriction, and its distribution depended on the onset of zygotic gene expression. In summary, we define zygotic transcription as a timer, to which subapical markers respond in a dia -dependent mechanism. [Display omitted] • Formation of the subapical domain is part of the mid-blastula transition during cellularization in Drosophila. • Initial formation of the subapical domain is triggered by the onset of zygotic transcription. • The formin Dia reponds to onset of zygotic transcription and is required for formation of the subapical domain. [ABSTRACT FROM AUTHOR]

Safe and satisfactory recreation experiences are embedded in the mission of multiple land use management agencies that support 5.2 million recreation-related jobs in the United States. However, visitors are often unaware of potential risks and safety hazards associated with recreation and subsequently unprepared. With the advent of online information, opportunities exist to target communications and key messages. This research observed water-based visitors against recommended safety behaviors as well as online messaging related to safety among public, private and non-profit organizations in the recreation area. Results indicate significant safety issues and multiple opportunities to use and enhance online communications to increase safe recreation behaviors. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the acute effect of an 8-week specific hamstring flexibility training on junior canoeist during the competition season. Sixteen canoeists participated, divided into 3 groups: 5 in experimental group 1 (EG1), 5 in experimental group 2 (EG2), and 6 in a control group. The EG1 underwent a supervised program consisted by simple static stretching, dynamic static stretching, and proprioceptive neuromuscular facilitation (PNF), whereas the EG2 performed a program without PNF and no supervision. Two measurements were performed to analyze the effect on the knee joint range of motion (ROM) and trunk flexion; neuromuscular and contractile properties in biceps femoris (BF) and semitendinosus (ST) muscles; and maximum power and average speed in lower limbs. A mixed-design factorial analysis of variance (p ≤ 0.05) was performed and the effect size was calculated. The results show significant improvements (p ≤ 0.05) in both legs for knee joint ROM and trunk flexion in EG1 (8.9 and 25.5%; 5.7 and 20.9% in the right and left leg, respectively) and EG2 (6.7 and 22%; 3.9 and 24.4%), only EG1 improved muscular stiffness in BF (27.4% left leg) and ST (20.5 and 24.3%), and lateral symmetry in BF (49%) without decreasing average speed in lower limbs. All improvements have a large effect size. In conclusion, it is suggested that a supervised hamstring flexibility program performed concurrently during a canoeist competition season can produce an increase in the knee joint ROM and trunk flexion, without negative repercussions in contractile and neuromuscular capacities, maximum power, and average velocity in lower limbs. [ABSTRACT FROM AUTHOR]

Introduction: Kayak racing has been an Olympic sport since 1936. The sport is evolving with the introduction of ocean skis and stand-up-paddle boards (SUP). Musculoskeletal injury incidence surveys have been conducted for ultra-marathon events, but no data have been published for other racing formats. Objective: To identify and compare the rates and types of injuries sustained by paddling athletes as a function of discipline and training parameters in Sprint, Marathon, Ultra-Marathon, and Ocean events. Methods: Competitors from 6 kayak and/or ocean surf-ski races in Australia were surveyed. Before each race, competitors were asked to complete a questionnaire. The questionnaire investigated paddling-related injuries over the previous 5 years, athlete morphology, flexibility, equipment and its setup, training volume, and environment. Results: Five hundred eighty-three competitors were surveyed. Disciplines included 173 racing-kayak (K1), 202 touring-kayak, 146 ocean-skis, 42 SUP, and 20 other. The top 5 paddling-related injuries were shoulder (31%), low back (23.5%), wrist (16.5%), neck (13.7%), and elbow (11.0%). The highest percentage of injury was found in K1 paddlers for shoulder (40.5%), SUP for low back (33.3%), and ocean-ski for wrist (22.6%). After controlling for on-water training hours, the relative risk (RR) of wrist injury was significantly increased in ocean-ski paddlers (1.86) and in paddlers with decreased flexibility (1.53-1.83). Relative risk of shoulder and low-back injury was significantly increased in athletes with lower training volumes (1.82-2.07). Younger athletes had lower RR of wrist and shoulder injury (0.58-0.62). [ABSTRACT FROM AUTHOR]

Drowning is the most common cause of death in recreational boating. Life jackets prevent drowning, yet adult wear rates remain relatively low on most types of boats. Canoes and kayaks are among the least used boat types, yet maintain the third and first highest annual boating-related drowning rates in 2012, respectively. This 1999-2017 study collected data from 124 study sites across the US. Life jacket wear was calculated for 13 dichotomized risky and non-risky variables, using Chi-square tests. A count variable based on number of risks was created, and Cochran-Armitage trend tests examined linearity in life jacket use. Three illustrative variables for each boat type were represented in tree diagrams. Kayakers had higher wear rates than canoeists among all variables observed. For both boats, the majority of risky conditions had higher life jacket wear rates than their non-risky alternatives. As the number of risks increased, life jacket wear rate increased. Boaters seemingly conduct a mental assessment of risk to determine whether to wear a life jacket. [ABSTRACT FROM AUTHOR]

Kayak racing performance is known to be dependent on technique, strength and equipment, but the relationship between these factors and performance is not well understood. Complete experimental measures of stroke technique and the interactions between the water and the paddle and the boat are not practical in a racing environment. Instead, simulation using computational fluid dynamics can be used to study this system. A coupled biomechanical-Smoothed Particle Hydrodynamics (B-SPH) model of the kayaking athlete is presented. Verification and validation of the model are confirmed using drag force data from the literature and a spatial resolution study. Using this model and stroke kinematics (developed from the combination of literature data and digitised motion of an amateur level athlete from video), calculations are made of (a) the fluid response to interactions with the paddle and kayak; (b) speed of the kayak; and (c) magnitudes of force and impulse on the paddle and the hands. Key features of the fluid response are related to the loading on the athlete and the speed of the kayak. Perturbations to stroke technique are explored to give new insights into the relationships between technique and racing performance. [ABSTRACT FROM AUTHOR]

Objective: We report the largest case series of shoulder injuries among paddlers so far to establish common mechanisms and patterns of injury. We also discuss how these injuries were managed and report the proportion of paddlers that return to paddlesport. Design: Case series. Setting: Upper Limb Unit, Wrightington Hospital, United Kingdom. Manchester Arm Clinic, United Kingdom. Patients: Fifty-seven shoulder injuries to professional and recreational paddlers were reviewed at a mean follow-up time of 55 months from the first consultation. The patient cohort had a mean age of 36 years and consisted of 56% males. Assessment of Risk Factors: Sex, mechanism of injury, acute/nonacute injury, and level of sport participation. Main Outcome Measures: Patient data were analyzed with regards to Constant score, QuickDASH score, and VAS satisfaction score before and after treatment. Results: The most common mechanism of injury was a capsize which accounted for 15 (26%) injuries. Ten injuries caused by a capsize were labral tears all of which needed surgery. A significant improvement in patient outcome scores was noted. Patients were able to return to a high level of paddling such as 3 slalom paddlers who returned to international competition; one of whom had bilateral surgery. Conclusions: Paddlers most commonly injure their shoulder when preventing a capsize, during a capsize or while rolling. The paddles strokes performed at these times often require paddlers to place their shoulder in a dangerous abducted and externally rotated position. We believe this is one of the commonest causes of serious shoulder injuries to paddlers. [ABSTRACT FROM AUTHOR]

The purpose was to examine power output and three-dimensional (3D) kinematic variables in the upper limbs, lower limbs and trunk in elite flat-water kayakers during kayak ergometer paddling. An additional purpose was to analyse possible changes in kinematics with increased intensity and differences between body sides. Six male and four female international level flat-water kayakers participated. Kinematic and kinetic data were collected during three tasks; low (IntL), high (IntH) and maximal (IntM) intensities. No differences were observed in any joint angles between body sides, except for shoulder abduction. Significantly greater range of motion (RoM) values were observed for IntH compared to IntL and for IntM compared to IntL in trunk and pelvis rotation, and in hip, knee and ankle flexion. The mean maximal power output was 610 ± 65 and 359 ± 33 W for the male and female athletes, respectively. The stroke frequencies were significantly different between all intensities (IntL 59.3 ± 6.3; IntH 108.0 ± 6.8; IntM 141.7 ± 18.4 strokes/min). The results showed that after a certain intensity level, the power output must be increased by other factors than increasing the joint angular RoM. This information may assist coaches and athletes to understand the relationship between the movement of the kayaker and the paddling power outp [ABSTRACT FROM AUTHOR]

This paper presents a development of a ductile alkali-activated fly ash (FA) and ground granulated blast furnace slag (GBFS) based composite as an environmentally friendly material for structural concrete application. For this purpose, polyvinyl alcohol (PVA) fibres and sand aggregate were combined with alkali-activated paste. Workability, setting time, mechanical properties and failure mode of PVA fibres in the mixture were studied by slump test, Vicat needle test, flexural and compression tests, and Scanning Electron Microscopy (SEM) imaging, respectively. Although the mixture sets in a short period of time (less than 30 min), the workability was good and the developed fibre reinforced composite was used for a large scale application in a canoe. Casting a large volume (45 l compared to 3 l, as initially designed) did not affect the workability and the setting time of the mixture. Mechanical properties of specimens coming from “small” (3 l) and “large” (45 l) batches were tested at different ages (up to 120 days) and compared. It was shown that their flexural and compressive strength are similar, i.e. not affected by the upscaling. Furthermore, it was shown that the mixture with PVA fibres exhibits deflection hardening behaviour even with aggregate particles as large as 4 mm, although single crack localization led to failure. The SEM images of fractured surfaces indicated that combined fibre pull-out and fibre rupture occurred, with the latter one causing the final failure. The developed mixture, additionally reinforced with the plastic fiberglass mesh, was used in the 5.8 m long and 16 mm thick canoe for the student competition, which for the very first time, was constructed without the use of Ordinary Portland cement (OPC). The upscaling was successful and the results show the potential of fibre-reinforced alkali-activated FA and GBFS composite to be used as a durable and resistant material suitable for the structural application in thin shell elements, exemplified by the canoe. Such an application and a low risk project was suitable to gain the necessary experience and confidence with this innovative, “concrete like”, material for which no codes or regulations are available. Furthermore, similar applications are the first step for larger scale structural applications, like structural elements in the building industry, bridges and other civil engineering structures. [ABSTRACT FROM AUTHOR]

When Tasman and Cook arrived in New Zealand in 1642 and 1769 respectively they both sighted double-hulled canoes (waka) on New Zealand's coast. However, over the next 100 or so years these canoes disappeared. Fortuitously the recent rescue and conservation of a waterlogged waka and fibrework assemblage on the shores of Papanui Inlet has allowed rare insight into the lives of its inhabitants nearly 550 years ago, when New Zealand's seminal migrants established themselves in the remote south of New Zealand. These discoveries reinforce traditional stories around early Māori occupation of Te Waipounamu and offer additional clarification of iwi 'tribal' activities in their local environment many generations ago. Conservation of these taoka 'treasures' on Ōtākou Marae has provided easy, continuous access for descendants of the waka to their taoka throughout the process and aided the development of constructive relationships for iwi and conservation and archaeological agencies. Here we discuss recent fieldwork with an emphasis on conservation, cross-cultural engagement and the assemblage recovered to date, followed by comparison of the waka reported here with another discovered within the Te Rūnanga o Ōtākou rohe 'territory' over 120 years ago by Elsdon Best. Imminent investigations to excavate cultural material from Papanui Inlet's actively degrading coastline are scheduled for January 2018, and the resulting environmental and archaeological information from this research will be discussed fully elsewhere. [ABSTRACT FROM AUTHOR]

Over the past decade an intriguing connection between asymmetric cell division, stem cells and tumorigenesis has emerged. Neuroblasts, which are the neural stem cells of the Drosophila central nervous system, divide asymmetrically and constitute an excellent paradigm for investigating this connection further. Here we show that the simultaneous loss of the asymmetric cell division regulators Canoe (afadin in mammals) and Scribble in neuroblast clones leads to tumor-like overgrowth through both a severe disruption of the asymmetric cell division process and canoe lossmediated Ras-PI3K-Akt activation. Moreover, canoe loss also interacts synergistically with scribble loss to promote overgrowth in epithelial tissues, here just by activating the Ras-Raf-MAPK pathway. discs large 1 and lethal (2) giant larvae, which are functionally related to scribble, contribute to repress the Ras-MAPK signaling cascade in epithelia. Hence, our work uncovers novel cooperative interactions between all thesewell-conserved tumor suppressors that ensure tight regulation of the Ras signaling pathway. [ABSTRACT FROM AUTHOR]

Cet article analyse les stratégies de reconnaissance d'une discipline olympique : le canoë de slalom. Il interroge en particulier les processus de difusion de ce sport en Afrique en étudiant précisément sa place en tant que discipline au sein du mouvement olympique. Mais comment la difusion d'un sport parmi les pays africains peut-elle cristalliser des enjeux nationaux? Pour comprendre la complexité de cet objet, le remaniement des aires culturelles issues du joug des empires coloniaux est interrogé. Il s'agit d'inscrire les perceptions de la participation olympique dans les rivalités où elles s'inscrivent depuis les Indépendances. L'enquête restitue l'apport de la nationalité comme critère d'éligibilité du sportif, en s'employant à relater les faits présidant à sa sélection olympique. Elle soulève la question des traditions : françaises et anglo-saxonnes à travers l'appropriation d'une culture sportive. Ce maniement des catégories de perception repose sur l'expression de lutes pour la légitimité de la représentation, en interrogeant le recours à la binationalité des sportifs. [ABSTRACT FROM AUTHOR]

This paper presents a rule-based energy management strategy for a plug-in hybrid school bus (PHSB). In order to verify the effectiveness and rationality of the proposed energy management strategy, the powertrain and control models were built with MATLAB/Simulink. The PHSB powertrain model includes an engine model, ISG (integrated started and generator) model, drive motor model, power battery packs model, driver model, and vehicle longitudinal dynamics model. To evaluate the controller area network (CAN) bus performance features such as the bus load, signal hysteresis, and to verify the reliability and real-time performance of the CAN bus multi-node control method, a co-simulation platform was built with CANoe and MATLAB/Simulink. The co-simulation results show that the control strategy can meet the requirements of the PHSB's dynamic performance. Meanwhile, the charge-depleting mode (CD) and charge-sustaining mode (CS) can switch between each other and maintain a state-of-charge (SoC) of around 30%, indicating that the energy management strategy effectively extends the working period of the CD mode and improves the fuel economy further. The energy consumption per 100 km includes 13.7 L diesel and 10.5 kW.h electricity with an initial SoC of 75%. The CANoe simulation results show that the bus communication performs well without error frames. [ABSTRACT FROM AUTHOR]

The goal of this report is to describe the process for designing, building and testing an ultra-lightweight canoe using finite-element analysis and aerospace construction techniques. This research was conducted as part of a year-long Honors Capstone, from August 2014 to May 2015. This project applied Finite-Element Analysis (FEA) techniques to carbon composite construction in an effort to set the unofficial world record for lightest human-carrying vessel. Based on a lightweight canoe design from 2007, the project used SolidWorks Simulation to create an FEA model of the canoe, which was used to evaluate the minimum necessary composite structure. The canoe was fabricated using vacuumbagging techniques, and primarily a cored single-ply layup. Included in the report is a summary of past attempts to build ultra-lightweight canoes, as well as an overview of the techniques necessary to design and build such a canoe. The full process for the design, fabrication, and testing of this project is also included. [ABSTRACT FROM AUTHOR]

The transition from canoe to steamship on the remote Skagit and Nooksack Rivers in Washington Territory occurred in a brief period of settlement in the nineteenth century. Diaries and historical accounts from the Pacific Northwest describe settlers' perceptions of mobility derived from communities they had left in their journey west. As they confronted an indigenous mode of travel rooted in place, they adapted and then usurped the canoe, bringing steamships to the Skagit and then Nooksack River. Steamship travel required a complex infrastructure of cleared rivers, supply chains, mechanical knowledge and observational navigation, linking travelers with a larger, regional network. The advent of steamships triggered significant environmental changes to the riverine landscape and the broader region. [ABSTRACT FROM AUTHOR]

It is firmly established that interactions between neurons and glia are fundamental across species for the correct establishment of a functional brain. Here, we found that the glia of the Drosophila larval brain display an essential non-autonomous role during the development of the optic lobe. The optic lobe develops from neuroepithelial cells that proliferate by dividing symmetrically until they switch to asymmetric/ differentiative divisions that generate neuroblasts. The proneural gene lethal of scute (l9sc) is transiently activated by the epidermal growth factor receptor (EGFR)-Ras signal transduction pathway at the leading edge of a proneural wave that sweeps from medial to lateral neuroepithelium, promoting this switch. This process is tightly regulated by the tissue-autonomous function within the neuroepithelium of multiple signaling pathways, including EGFR-Ras and Notch. This study shows that the Notch ligand Serrate (Ser) is expressed in the glia and it forms a complex in vivo with Notch and Canoe, which colocalize at the adherens junctions of neuroepithelial cells. This complex is crucial for interactions between glia and neuroepithelial cells during optic lobe development. Ser is tissue-autonomously required in the glia where it activates Notch to regulate its proliferation, and non-autonomously in the neuroepithelium where Ser induces Notch signaling to avoid the premature activation of the EGFR-Ras pathway and hence of L9sc. Interestingly, different Notch activity reporters showed very different expression patterns in the glia and in the neuroepithelium, suggesting the existence of tissue-specific factors that promote the expression of particular Notch target genes or/and a reporter response dependent on different thresholds of Notch signaling. [ABSTRACT FROM AUTHOR]

Cet article repose sur une enquête sur les usages sociaux du canoë en Zambie. Il a pour objectif de décrire les caractéristiques des relations sociales qui se nouent entre étrangers et « populations locales ». Si l'organisation de l'activité recouvre une visée touristique pour nombre de pays africains, touristes et habitants entrent peu en interaction en dehors de la pratique des loisirs. Pour étudier l'identité, il s'agit de caractériser la genèse du tour en canoë afin de saisir l'émergence de modes d'appréhension de l'Autre dans le cadre du loisir en Zambie. La singularité des relations sociales entre populations occidentales et africaines pose la question de la différence culturelle, au moment où la globalisation introduit à la fois une homogénéisation des pratiques et une fragmentation dans les modes de vie. L'article proposera une réflexion critique car les modes de structuration du canoë constituent un révélateur des rapports toujours ambivalents entre pays occidentaux et africains. [ABSTRACT FROM AUTHOR]

In this essay, I consider how the nation might be evoked via reiterations of the canoe and contemplate why this boat might be a compelling means of attachment to the Canadian nation. Through reading canoe artifacts as they emerge in a variety of cultural spaces, I explore how the boat is usually read as a benign or simple symbol, but how its symbolism can be more complex and can be reappropriated. The canoe often calls up a version of Canada that predominantly reflects the desires of a dominant, settler/invader society and thus calls up a Canada that may exclude Aboriginal and broader immigrant communities and histories. In the end, the canoe and the practice of canoeing perhaps confer national belonging, yet they are contradictory in the ways that they do so. [ABSTRACT FROM AUTHOR]

Abstract: Mechanisms that govern cell-fate specification within developing epithelia have been intensely investigated, with many of the critical intercellular signaling pathways identified, and well characterized. Much less is known, however, about downstream events that drive the morphological differentiation of these cells, once their fate has been determined. In the Drosophila wing-blade epithelium, two cell types predominate: vein and intervein. After cell proliferation is complete and adhesive cell–cell contacts have been refined, the vast majority of intervein cells adopt a hexagonal morphology. Within vein territories, however, cell-shape refinement results in trapezoids. Signaling events that differentiate between vein and intervein cell fates are well understood, but the genetic pathways underlying vein/intervein cyto-architectural differences remain largely undescribed. We show here that the Rap1 GTPase plays a critical role in determining cell-type-specific morphologies within the developing wing epithelium. Rap1, together with its effector Canoe, promotes symmetric distribution of the adhesion molecule DE-cadherin about the apicolateral circumference of epithelial cells. We provide evidence that in presumptive vein tissue Rap1/Canoe activity is down-regulated, resulting in adhesive asymmetries and non-hexagonal cell morphologies. In particular Canoe levels are reduced in vein cells as they morphologically differentiate. We also demonstrate that over-expression of Rap1 disrupts vein formation both in the developing epithelium and the adult wing blade. Therefore, vein/intervein morphological differences result, at least in part, from the patterned regulation of Rap1 activity. [Copyright &y& Elsevier]

Did the first East Polynesian settlers of New Zealand, as opposed to discoverers, maintain even a short period of contact with their tropical homeland after arrival? While there is currently no evidence to suggest that contact was maintained the possibility has remained open. Recent revivals of Polynesian ocean voyaging and waka ama paddling in New Zealand have given rise to a general belief that that Māori, like their kin in tropical Polynesia, never lost the arts of long-distance ocean voyaging. This paper, however, argues a contrary position and suggests that our isolation, size, abundance of resources, along with recent revisions to the date of initial settlement in New Zealand, further diminishes the possibility of contact with the tropical Polynesian homelands in the prehistoric past. [ABSTRACT FROM AUTHOR]

Objective: To present the diagnostic and clinical features of an intraosseous ganglion cyst of the humeral head of a female flat water canoe athlete. Clinical Features: An 18-year old female flat water canoeist complaining of right shoulder pain following a strenuous paddling training camp. Intervention and outcome: A trial of passive care was conducted, including soft tissue therapy, spinal manipulative therapy, acupuncture, and rehabilitation. The patient seemed to be responding with treatment, but pain would always resume with paddling. A diagnostic ultrasound displayed mild thickening and effusion in the subacromial/subdeltoid bursae. Continued passive care was not able to resolve the symptoms and she underwent an MRI which revealed an intraosseus ganglion cyst subjacent to the lesser tuberosity and floor of the intertubercular groove. A subsequent MRA was ordered to assess the labrum, which was intact, but the cyst had progressed in size. She was referred to an orthopedic surgeon who performed surgery. Conclusion: An IOG cyst within the humeral head is a rare, potentially painful condition that can mimic other pathologies including impingement and labral tear. It is important to be aware of the clinical features to obtain a prompt diagnosis and appropriate treatment of this condition. [ABSTRACT FROM AUTHOR]

Background: Regular physical activity has a favorable effect upon the prevention and treatment of hypertension. Various movements in sports, however, affect blood pressure (BP) differently. Methods: In the present study, the resting BP data of a large number (3,697) of young men and women (age: 19-40 years) who participated in sports medical examinations were compared according to their sport. Athletes were arranged into definite subgroups based on their different sport activities, i.e. if their movement pattern characteristics were similar and no significant intergroup differences were seen in BP values. Results: BP values were lower in the dynamic type athletes (speed, endurance sports and ball games) than in the static type. Out of the endurance athletes, BP values were not lower in cycle racers, kayakers/canoeists and rowers. In water athletes, BP values were higher than in corresponding dry-land athletes. There was a quite large significant difference between the BP values of athletes involved in static muscular activity (power athletes) and dynamic-type strength athletes (combat competitors). Conclusions: Although cycling, kayaking/canoeing and competitive water sports increase BP, as leisure time activities they more than likely do not elevate BP. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

In this study, we investigated the effect of hull dynamics in shallow water on the hydrodynamic performance of rowing shells as well as canoes and kayaks. An approach was developed to generate data in a towing tank using a test rig capable of reproducing realistic speed profiles. The impact of unsteady shallow-water effects on wave-making resistance was examined via experimental measurements on a benchmark hull. The data generated were used to explore the validity of a computational approach developed to predict unsteady shallow-water wave resistance. Comparison of measured and predicted results showed that the computational approach correctly predicted complex unsteady wave-resistance phenomena at low oscillation frequency and speed, but that total resistance was substantially under-predicted at moderate oscillation frequency and speed. It was postulated that this discrepancy arose from unsteady viscous effects. This was investigated via hot-film measurements for a full-scale single scull in unsteady flow in both towing-tank and field-trial conditions. Results suggested a strong link between acceleration and turbulence and demonstrated that the measured real-world viscous-flow behaviour could be successfully reproduced in the tank. Thus a suitable tank-test approach could provide a reliable guide to hull performance characterization in unsteady flow. [ABSTRACT FROM AUTHOR]

Abstract: The small GTPase Rap1 affects cell adhesion and cell motility in numerous developmental contexts. Loss of Rap1 in the Drosophila wing epithelium disrupts adherens junction localization, causing mutant cells to disperse, and dramatically alters epithelial cell shape. While the adhesive consequences of Rap1 inactivation have been well described in this system, the effects on cell signaling, cell fate specification, and tissue differentiation are not known. Here we demonstrate that Egfr-dependent cell types are lost from Rap1 mutant tissue as an indirect consequence of DE-cadherin mislocalization. Cells lacking Rap1 in the developing wing and eye are capable of responding to an Egfr signal, indicating that Rap1 is not required for Egfr/Ras/MAPK signal transduction. Instead, Rap1 regulates adhesive contacts necessary for maintenance of Egfr signaling between cells, and differentiation of wing veins and photoreceptors. Rap1 is also necessary for planar cell polarity in these tissues. Wing hair alignment and ommatidial rotation, functional readouts of planar cell polarity in the wing and eye respectively, are both affected in Rap1 mutant tissue. Finally, we show that Rap1 acts through the effector Canoe to regulate these developmental processes. [Copyright &y& Elsevier]

The canoe has become a material metaphor for the intrepid skill and ancient knowledge of ancestral indigenous migrations and connections and a popular culture symbol of identity in Oceania. I examine the central role played by the ‘great canoes’ of the ancestors in Pacific literature, especially as the canoe is identified with the mauri or ‘spirit of the land’ in two well-known novels, The Whale Rider by Witi Ihimaera and The Bone People by Keri Hulme. The representations of incest, violence against very young women and sexual possession linked to the site of a canoe stone in the first Kanak novel... [ABSTRACT FROM AUTHOR]

The aim of this study was to quantify the differences between groups of elite canoe slalom athletes based on the class they paddle in and the strategies they use in competition. Canoe and kayak footage was recorded using three cameras and analysed using lapsed-time time-motion analysis. Analysis was undertaken on the ten fastest competition runs for men's kayak and canoes and women's kayak for the 22-gate semi-final/final course at the 2005 canoe slalom world championships. Comparison between the categories of paddlers revealed that despite canoe paddlers taking significantly (P ≤ 0.05) fewer strokes than kayak paddlers, they were not significantly slower than men's single kayak paddlers with respect to their run times and only significantly slower between 4 of 22 gates. Results revealed also that paddlers using different turn strategies (spin vs. pivot) had significantly (P ≤ 0.05) different split times for the gates before and after the execution of the manoeuvre. For a paddler this means that their individual strategy could be analysed and compared with those of others to determine if alternate strategies would be beneficial to their performance. [ABSTRACT FROM AUTHOR]

Abstract: A finite element model is set up and experimental tests are performed to help understand the behavior of a concrete canoe and subsequently optimize its design. First, the performance criteria that must be satisfied to participate at the annual ASCE/Master Builders competition are described. Then, the finite element model and the different loading cases that were studied are presented. Results from these loading cases are discussed and used to optimize the material properties as well as the thickness of the hull and the dimensions of the gunwale and reinforcing ribs. Static and dynamic experimental tests were also conducted to validate the results of the finite element analyses. The results indicate that the main stresses and strains are caused by the static load cases. The additional stresses caused during races are small. [Copyright &y& Elsevier]

In discussing ways that monumental architecture symbolises political power, I suggest that vehicles are a unique category of monument construction. Their ability to travel, and to be used for politically momentous tasks, increases the prestige of the rulers who make use of them. The Lomipeau , a large double‐hulled canoe used by Tongan rulers in the sixteenth century, exemplifies the concept of a monumental vehicle. To demonstrate the concept, I examine the origins of the canoe, the archaeology of sites associated with its exploits, and its use in ceremonial voyages of national importance. Identifying vehicles as a distinctive class of monumental architecture in future studies will help us to comprehend the complex variety of ways leaders express power across cultures. [ABSTRACT FROM AUTHOR]

Summary: Objective: The objective of this study was to estimate the total fat, saturated, monounsaturated, polyunsaturated fatty acids and cholesterol intake by sportsmen practicing slalom canoe racing and sport-shooting. Material and methods: The studies were performed at 29 slalom canoe's racing and at 23 sport's shooting sportsmen. Twenty-four-hour dietary recalls were collected in training and start period of 2009, for three selected days per week (including Friday and Sunday, due to the different, eating habits in Poland). Results: The obtained amount of total fats intake in average daily diet of canoeist and shooters were 29% and 34% of total energy, respectively. The saturated fatty acids delivered –16% and 17% of total energy, respectively. The percentage of monounsaturated fatty acids was in accordance with recommendations (above 10% of total energy of daily diets), whereas for n-3 family polyunsaturated fatty acids, especially the docosahexaenoic acid and eicosapentaenoic acid, were too low (below 1% of energy of daily diets). However the proper ratio of n-6 to n-3 (5–6:1) were found. Conclusions: It is therefore reasonable to increase consumption of fatty sea fish, canola and flax seeds oil rich in n-3 family fatty acids by sportsmen. [Copyright &y& Elsevier]