High accuracy alignment facility for the receiver and transmitter of the BepiColombo Laser Altimeter

The accurate co-alignment of the transmitter to the receiver of the BepiColombo Laser Altimeter is a challenging task for which an original alignment concept had to be developed. We present here the design, construction and testing of a large collimator facility built to fulfill the tight alignment requirements. We describe in detail the solution found to attenuate the high energy of the instrument laser transmitter by an original beam splitting pentaprism group. We list the different steps of the calibration of the alignment facility and estimate the errors made at each of these steps. We finally prove that the current facility is ready for the alignment of the flight instrument. Its angular accuracy is 23 μrad.

Augmenting the effective field of view of optical tracking cameras--a way to overcome difficulties during intraoperative camera alignment

An Internet survey demonstrated the existence of problems related to intraoperative tracking camera set-up and alignment. It is hypothesized that these problems are a result of the limited field of view of today's optoelectronic camera systems, which is usually insufficiently large to keep the entire site of surgical action in view during an intervention. A method is proposed to augment a camera's field of view by actively controlling camera orientation, enabling it to track instruments as they are used intraoperatively. In an experimental study, an increase of almost 300% was found in the effective volume in which instruments could be tracked.

Precise estimation of postoperative cup alignment from single standard X-ray radiograph with gonadal shielding

This paper addresses the problem of estimating postoperative cup alignment from single standard X-ray radiograph with gonadal shielding. The widely used procedure of evaluation of cup orientation following total hip arthroplasty using single standard anteroposterior radiograph is known inaccurate, largely due to the wide variability in individual pelvic position relative to X-ray plate. 2D-3D image registration methods have been introduced to estimate the rigid transformation between a preoperative CT volume and postoperative radiograph(s) for an accurate estimation of the postoperative cup alignment relative to an anatomical reference extracted from the CT data. However, these methods require either multiple radiographs or a radiograph-specific calibration, both of which are not avaiable for most retrospective studies. Furthermore, these methods were only evaluated on X-ray radiograph(s) without gonadal shielding. In this paper, we propose to use a hybrid 2D-3D registration scheme combining an iterative landmark-to-ray registration with a 2D-3D intensity-based registration to estimate the rigid transfromation for a precise estimation of cup alignment. Quantitative and qualitative results evaluated on clinical and cadaveric datasets are given which indicate the validity of our approach.

Exploring the World's Largest ERP Implementation: the Role of ERP in Strategic Alignment

As one of the largest and most complex organizations in the world, the Department of Defense (DoD) faces many challenges in solving its well-documented financial and related business operations and system problems. The DoD is in the process of implementing modern multifunction enterprise resource planning (ERP) systems to replace many of its outdated legacy systems. This paper explores the ERP implementations of the DoD and seeks to determine the impact of the ERP implementations on the alignment of the DoD’s business and IT strategy. A brief overview of the alignment literature and background on ERP are followed by case study analysis of the DoD ERP development and current implementation status. Lastly, the paper explores the current successes and failures of the ERP implementation and the impact on the DoD’s goal of strategic alignment.

The effectiveness of laceback ligatures during initial orthodontic alignment: a systematic review and meta-analysis

Lacebacks may be used to limit unwanted incisor proclination during initial orthodontic alignment; however, their use has not met with universal approval. This systematic review aims to appraise the evidence in relation to the effectiveness of lacebacks in controlling incisor position during initial alignment. Electronic database searches of published literature (MEDLINE via Ovid, Cochrane Central Register of Controlled Trials, LILACS, and IBECS) and unpublished literature were performed. Search terms used included randomized controlled trial, controlled clinical trial, random allocation, double blind method, orthodontics, and laceback. Data were extracted using custom forms. Risk of bias assessment was made using the Cochrane Collaboration risk of bias tool. The quality of the evidence was also assessed using GRADE. Mean differences in incisor inclination and antero-posterior changes in incisor and molar position during alignment were calculated. Two studies involving 97 participants were found to be at low risk of bias and were included in the quantitative synthesis. The random effects meta-analysis demonstrated that the use of lacebacks was associated with 0.5 mm greater posterior movement of the incisors during alignment; this finding was of limited clinical importance and statistically non-significant [95 per cent confidence interval (CI): -1.25, 0.25, P = 0.19]. Little difference (0.46 mm) was also found between laceback and non-laceback groups with regards to mesial molar movement (95 per cent CI: -0.33, 1.24, P = 0.26). According to the GRADE assessment, the overall quality of evidence relating to the use of lacebacks was high. There is no evidence to support the use of lacebacks for the control of the sagittal position of the incisors during initial orthodontic alignment.

Sportvereine als Interessenorganisationen?! – Ursachen und Auswirkungen von Ziel-Interessen-Divergenzen in freiwilligen Sportorganisationen

Für Sportvereine als Interessenorganisationen scheint die Rückbindung der Vereinsziele an die Mitgliederinteressen von zentraler Bedeutung zu sein. In der Vereinsrealität dürfte aber diese Rückbindung nur teilweise gewährleistet sein und folglich Ziel-Interessen-Divergenzen eher die Norm als die Ausnahme darstellen. Vor diesem Hintergrund stellt sich die Frage, welche Ursachen für Ziel-Interessen-Divergenzen verantwortlich zu machen sind und welche Auswirkungen sich daraus für die Vereine ergeben. Dieser Frage geht der vorliegende Beitrag nach, indem auf der Grundlage des Akteurtheoretischen Mehr-Ebenen-Modells zur Analyse der Entwicklung von Sportvereinen die struktur- und handlungsbedingten Ursachen und Auswirkungen von Divergenzen auf der Vereins- und Mitgliederebene beleuchtet werden. Mit Blick auf die Ursachen wurde der Einfluss der korporativen Vereinsstrukturen und der individuellen Handlungsorientierungen der Mitglieder auf Divergenzen untersucht. Die Befunde hierzu zeigen, dass Divergenzen einerseits durch einem zunehmenden Differenzierungs- und Hierarchisierungsgrad (z.B. Vereinsgröße, Umweltvernetzung, Oligarchisierung) begünstigt werden und andererseits vor allem bei einer primären Verfolgung von Eigeninteressen der Mitglieder auftreten. Hinsichtlich der Auswirkungen wurden die individuellen Mitgliederreaktionen und die korporativen Vereinsreaktionen auf Divergenzen analysiert. Diesbezüglich zeigen die Befunde, dass sowohl die Mitglieder als auch die Vereinsführung überwiegend konstruktiv auf Divergenzen reagieren (z.B. durch Problemansprache, Vertrauen, Kompromissfindung), so dass es vielen Vereinen offenbar relativ gut gelingt, Ziel-Interessen-Divergenzen bis zu einem gewissen Grad sowohl aushalten als auch aufarbeiten zu können.

The biomechanics of the hip joint using new diagnostic aspects in the field of hip joint dysplasia. Constructive criticism of hip dysplasia diagnosis and present marketable breeding methods with an outlook on future perspectives and possibilities. Part I

In absence of basic canine hip biomechanics, a specific, consequent three dimensional concept to evaluate the coxofemoral joint was developed for the dog. With the help of a new method to radiologically demonstrate the hip in a physiological standing position several new clinically relevant aspects could be further investigated. For example the breed specific anatomical differences in the hip, and dynamics and the background on "iatrogenic luxations" in HD diagnostics could be shown. The caudal luxation and the growth abnormalities of the hip and their consequences on the whole leg (antetorsion syndrome) as a consequence of inadequate breeding could be demonstrated.

Virtual tissue alignment and cutting plane definition--a new method to obtain optimal longitudinal histological sections.

Histomorphometric evaluation of the buccal aspects of periodontal tissues in rodents requires reproducible alignment of maxillae and highly precise sections containing central sections of buccal roots; this is a cumbersome and technically sensitive process due to the small specimen size. The aim of the present report is to describe and analyze a method to transfer virtual sections of micro-computer tomographic (CT)-generated image stacks to the microtome for undecalcified histological processing and to describe the anatomy of the periodontium in rat molars. A total of 84 undecalcified sections of all buccal roots of seven untreated rats was analyzed. The accuracy of section coordinate transfer from virtual micro-CT slice to the histological slice, right-left side differences and the measurement error for linear and angular measurements on micro-CT and on histological micrographs were calculated using the Bland-Altman method, interclass correlation coefficient and the method of moments estimator. Also, manual alignment of the micro-CT-scanned rat maxilla was compared with multiplanar computer-reconstructed alignment. The supra alveolar rat anatomy is rather similar to human anatomy, whereas the alveolar bone is of compact type and the keratinized gingival epithelium bends apical to join the junctional epithelium. The high methodological standardization presented herein ensures retrieval of histological slices with excellent display of anatomical microstructures, in a reproducible manner, minimizes random errors, and thereby may contribute to the reduction of number of animals needed.