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Background: Despite advances in surgical techniques, the use of maximal repair to treat large or massive rotator cuff tears results in a high retear rate postoperatively. Currently, no randomized controlled trials have compared the outcomes of maximal repair with interposition dermal allograft bridging reconstruction. Hypothesis: We hypothesized that large or massive rotator cuff tendon tears reconstructed using bridging dermal allograft would have better clinical outcomes 2 years postoperatively, as measured using the Western Ontario Rotator Cuff (WORC) index, than would those receiving the current gold standard treatment of debridement and maximal repair alone. We also expected that patients treated via bridging reconstruction using dermal allograft would have fewer postoperative failures as assessed using postoperative magnetic resonance imaging scans. Study Design: Randomized controlled trial; Level of evidence 1. Methods: A sample size of 30 patients (determined using a priori sample size calculation) with massive, retracted rotator cuff tears were randomly allocated to 1 of 2 groups: maximal repair or bridging reconstruction using dermal allograft. All patients completed questionnaires (WORC and Disabilities of the Arm, Shoulder and Hand [DASH]) preoperatively and postoperatively at 3 months, 6 months, 1 year, and 2 years. The primary outcome of this study was the WORC index at 2 years. Secondary outcomes included healing rate, progression of rotator cuff arthropathy, and postoperative acromiohumeral distance in both groups. Results: Patients treated via bridging reconstruction using dermal allograft had better postoperative WORC and DASH scores (23.93 ± 24.55 and 15.77 ± 19.27, respectively) compared with patients who received maximal repair alone (53.36 ± 31.93 and 34.32 ± 23.31, respectively). We also noted increased progression to rotator cuff arthropathy in the maximal repair group with an increased retear rate when compared with the reconstruction group (87% and 21%, respectively; P < .001). The acromiohumeral distance was maintained in the reconstruction group but significantly decreased in the maximal repair group. Conclusion: Rotator cuff bridging reconstruction using a dermal allograft demonstrated improved patient-reported outcomes as measured using the WORC index 2 years postoperatively. This technique also showed favorable structural healing rates and decreased progression to arthropathy compared with maximal repair. Trial Registration: ClinicalTrials.gov (NCT01987973)

To evaluate the effectiveness of celecoxib, a selective cyclooxygenase 2 inhibitor, in reducing heterotopic ossification (HO) after hip arthroscopic surgery and to evaluate celecoxib's impact on clinical outcomes.We performed a retrospective review of patients who received hip arthroscopy performed by the same surgeon between January 1, 2012, and December 31, 2016. Patients who had an allergy to sulfa drugs, had pre-existing HO or previous surgery on the operative side, or failed to complete radiographic follow-up at 6 months postoperatively were excluded. Patients in the treatment group received 400 mg of celecoxib postoperatively for 6 weeks, whereas the control group received no postoperative celecoxib. The incidence of HO was assessed using anteroposterior radiographs obtained at 6 months, 1 year, and 2 years postoperatively. Patients completed the International Hip Outcome Tool 33 survey, and the proportion of patients who met the minimal clinically important difference, substantial clinical benefit (SCB), and absolute SCB was calculated.A total of 559 patients were identified. After application of the exclusion criteria, 454 patients were included in the study (211 in control group and 243 in treatment group). The overall incidence of HO was 20.3% (n = 92). The treatment group had a significantly lower incidence of HO at 6 months (P = .006), 1 year (P.001), and 2 years (P = .008) postoperatively. At 2 years postoperatively, the treatment group had a significantly higher International Hip Outcome Tool 33 score on average: 64.2 versus 57.3 (P = .023). No significant difference in the proportion of patients reaching the minimal clinically important difference, SCB, or absolute SCB was found at any of the postoperative time points.The findings of this study suggest that a prophylactic treatment regimen of 400 mg of celecoxib once daily for 6 weeks significantly reduces the incidence of HO formation after hip arthroscopic surgery; however, it did not impact clinical outcomes.Level III, retrospective, comparative case-control study.

In this study, we aimed to evaluate the medium-term clinical outcomes for patients who underwent bridging reconstruction.A retrospective chart review was conducted for all patients who underwent bridging reconstruction between 2010 and 2018. Patients who were missing either pre- or postoperative outcome scores were excluded. All included patients completed self-reported questionnaires (Western Ontario Rotator Cuff [WORC] and Disabilities of the Arm, Shoulder and Hand [DASH]) pre- and postoperatively at 6 months, 1 year, and annually thereafter. All scores were reported out of 100.Ninety-one patients initially met our inclusion criteria, and 33 were excluded owing to lack of either pre- or postoperative outcome scores. Nine patients were lost to follow-up; therefore, 49 patients were finally evaluated, including 30 males (61.2%) and 19 females (38.8%) with an age of 59.6 ± 10.4 years (mean ± standard deviation) and mean follow-up of 5.3 years (range 2 to 9). Both WORC and DASH scores significantly improved from pre- to postoperatively (WORC: 69.6 ± 12.2 to 27.9 ± 23.7, P.001; DASH: 51.5 ± 17.5 to 24.5 ± 23.0, P = .001). For WORC and DASH, 92% and 74% of patients, respectively, met the minimal clinical importance difference.Our results showed that patients' clinical outcome scores significantly improved with an average of 5-year follow-up, which demonstrates that bridging reconstruction is a safe procedure with promising midterm clinical outcomes.IV, retrospective case series.

Objectives: To determine healing rate of rotator cuff reconstruction with an acellular human dermal allograft compared with the gold standard arthroscopic maximal rotator cuff repair of large, chronic tears of the rotator cuff. Methods: Thirty patients with a two-tendon chronic retracted rotator cuff tear were enrolled in the study and were randomly allocated (15) to each group. All the patients were evaluated for structural integrity of repair using a 1.5T MRI at an average of 15 months after surgery. Rotator cuff arthropathy (RCA) and acromio-humeral distance (AHD) were graded using X-rays. Western Ontario Rotator Cuff (WORC), Disabilities of the Arm, Shoulder, and Hand (DASH), Marx Activity Rating Scale (MARX) scores, range of motion (ROM) of shoulder were analyzed. Results: The re-tear rate in the reconstruction group was 13% (2 of 15 patients) compared to 73% (11/15) in the repair group (p=0.008). Progression of RCA was seen in 7% (1/15) and 35.71% (5/15) of patients in the reconstruction and repair group, respectively (p=0.006). The change in AHD (preop-postop) was significantly higher in the repair (reduced by 2.27 mm) than the reconstruction group (increased by 0.1 mm) (P=0.006). Both groups had significant improvements in patient reported outcome scores. The reconstruction group had statistically significant better forward flexion (p= 0.01) and scapular plane abduction (p=0.03) compared to the repair group. Conclusions: Rotator cuff reconstruction with a dermal allograft demonstrated favorable structural healing rates and improved range of motion compared to maximal repair in the short term. Moreover, the maximal repair group were more likely to develop RCA than reconstruction. Angle at which apprehension disappears Less than 60 degrees(n = 55) 60 degrees or more(n = 21) Significance Caton-Deschamps Index 1.12 ± 0.12 1.19 ± 0.19 P = 0.036 Trochlear Dysplasia P < 0.001 None or Dejour A 50 (91%) 10 (48%) Dejour B, C, or D 5 (9%) 11 (52%) Sulcus Angle (degrees) 156 ± 12 168 ± 17 P < 0.001 Sulcus Depth (mm) 2.5 ± 1.5 1.2 ± 1.7 P = 0.002 TT-TG Distance (mm) 18.3 ± 7.3 24.6 ± 10.3 P = 0.004

Background:The Latarjet procedure for autograft transposition of the coracoid to the anterior rim of the glenoid remains the most common procedure for reconstruction of the glenoid after shoulder instability. The anatomic glenoid reconstruction using distal tibial allograft has gained popularity and is suggested to better match the normal glenoid size and shape. However, concerns about decreased healing and increased resorption arise when an allograft bone is used.Purpose:To use radiological findings to evaluate the arthroscopic reconstruction of the glenoid with respect to the size, shape, healing, and resorption of coracoid autograft versus distal tibial allograft.Study Design:Cohort study; Level of evidence, 3.Methods:A retrospective review was performed of 48 consecutive patients who had an arthroscopic bony reconstruction of the glenoid (12 coracoid autograft, 36 distal tibial allograft), diagnosed anterior shoulder instability, and computed tomography (CT)–confirmed glenoid bone loss more than 20%. Coracoid autograft was performed only when tibial allograft was not accessible from a bone bank. Two fellowship-trained musculoskeletal radiologists reviewed pre- and postoperative CT scans at a minimum follow-up of 6 months for the following: graft position, glenoid concavity, cross-sectional area, width, version, total area, osseous union, and graft resorption. Clinical outcome was noted in terms of instability, subluxation, and dislocation at a minimum follow-up of 2 years. Simple logistic regression, 2-tailed independent-sample t tests, paired t tests, and Fisher exact tests were performed.Results:Graft union was seen in 9 of the 12 patients (75%) who had coracoid autograft and 34 of the 36 patients (94%) who had tibial allograft (odds ratio, 5.66; 95% CI, 0.81-39.20; P = .08). The odds ratio comparing allograft to coracoid for overall resorption was 7.00 (95% CI, 1.65-29.66; P = .008). Graft resorption ≥50% was seen in 3 (8%) of the patients who had tibial allograft and none of the patients who had coracoid autograft. Graft resorption less than 50% was seen in the majority of patients in both groups: 27 (73%) patients with tibial allograft and 5 (42%) patients with coracoid autograft. No statistically significant difference was found between the 2 procedures regarding anteroposterior diameter of graft ( P = .81) or graft cross-sectional area ( P = .93). However, a significant difference was observed in step formation between the 2 procedures ( P < .001). Two patients experienced subluxations in the coracoid group (16%) as well as 2 patients in the tibial allograft group (6%) with a P value of .25.Conclusion:Arthroscopic anatomic glenoid reconstruction via distal tibial allograft showed similar bony union but higher resorption compared with coracoid autograft. Even so, no statistically significant difference was found between the 2 procedures regarding final graft surface area, the size of grafts, and the anteroposterior dimensions of the reconstructed glenoids. These short-term results suggest that distal tibial allografts can be used as an alternative to coracoid autograft in the recreation of glenoid bony morphologic features.

Transmission efficiency and refinement of planetary wheel hub gearing system are key design attributes for heavy and off-highway vehicles. Reduction of power loss, directly leading to the development of new generation ECO-axles requires analysis of gear contacting conditions for lubricated conjunctions to determine frictional performance. This is also affected by gear dynamics, which is a prerequisite for assessment of noise, vibration and harshness performance. Therefore, a combined tribo-dynamic analysis is essential. There is a dearth of such holistic analysis, particularly for the case of wheel hub planetary systems. The paper presents such an analysis, which has not hitherto been reported in literature. The inexorable interplay of transmission efficiency and noise, vibration and harshness refinement is demonstrated. The key attributes of noise, vibration and harshness refinement and transmission efficiency can pose contrary requirements and near-optimal conditions can be highlighted by mesh phasing of gearing contacts, thus alleviating the need for more complex gear teeth modifications entailing prohibitive manufacturing costs.

Objective To investigate how the distance between narrow implants and adjacent teeth influences the marginal bone levels (MBL) up to 3 years after placement. Material and Methods A prospective, single-arm, multicenter clinical study was designed to include patients missing 12, 22, 32, 31, 41 or 42 teeth. Implants of 3.0 mm diameter and different lengths were used in the study. One-stage surgery was performed and healing abutments placed during the 6–10 weeks healing period. Clinical and radiographic evaluation was performed at implant installation, loading, and at the 6, 12, 24 and 36-months follow-up visits. Results Eighty-three implants were placed in 59 patients. A total of 48 implants were placed in narrow implant-to-tooth spaces (percentile 25, 0.83(0.25) mm), 80 in regular spaces (percentile 25

Purpose: For patients with narrow, single-tooth edentulous ridges as a result of permanent tooth agenesis (hypodontia) in the maxillary lateral and mandibular incisor regions, dental implant treatment may present a reliable and predictable restorative treatment solution. The aim of the present study was to evaluate the clinical reliability and outcome of small-diameter dental implants placed in a one-stage procedure with early loading replacing maxillary lateral or mandibular incisor teeth. Materials and Methods: Patients with hypodontia in the maxillary lateral incisor or mandibular incisor region analyzed in this report were selected from a larger prospective multicenter study. Small-diameter dental implants (AstraTech OsseoSpeed TX 3.0 S, Dentsply) of different lengths were placed using a one-stage surgical protocol with a 6- to 10-week healing period before loading. Probing pocket depth, bleeding on probing, and gingival zenith score were assessed after 6, 12, 24, and 36 months. Radiographic examination was assessed at 6, 12, and 36 months. Results: In total, 38 patients were included in this analysis and 62 small-diameter implants were placed. The mean distance between adjacent teeth was 6.30 mm (SD: 1.36). All patients received a titanium transmucosal abutment and cement-retained ceramic crown after 6 to 10 weeks of healing. Two implants were lost during the healing period before loading, providing a total implant survival rate of 96.8%. No implant fractures were reported. Mean marginal bone level change from surgery to follow-up visits at 6, 12, and 36 months were 0.39 mm, 0.22 mm, and 0.23 mm, respectively. The condition of soft tissue was stable at all follow-up visits with clinically insignificant changes in probing depth, bleeding on probing, and gingival zenith score. Conclusion: This study evaluated the behavior over 36 months of AstraTech Osseospeed TX 3.0 S dental implants placed into narrow one-tooth defect edentulous ridges as a result of hypodontia. The data collected highlighted the stability of the marginal bone level and soft tissues around the dental implants in conjunction with durable mechanical function. Small-diameter implants can be considered a valid solution in the restorative treatment of hypodontia in the maxillary lateral and mandibular incisor regions.

The vast majority of optical links within the data center are based on vertical cavity surface emitting lasers (VCSELs) operating at 850 nm over multimode optical fiber. Deployable links have evolved in speed from 1 Gb/s in 1996 to 28 Gb/s in 2014. Serial data links at 40 and 56 Gb/s are now under development and place even more demand on the VCSEL and photodiodes. In this paper, we present the characteristics of VCSELs and photodiodes used in current generation 28 Gb/s links and present several methods to extend link distances using more advanced data encoding schemes. Finally, we will present results on wavelength division multiplexing on multimode optical fiber that demonstrate 40 Gb/s Ethernet connections up to 300 m on duplex OM3 optical fiber, and present results on fiber optimized for modal bandwidth in the 850 to 980 nm range.

Beta thalassemia dominant results from mutations in the β globin chain gene resulting in the production of elongated, highly unstable β globin chains. Several such mutations have been described and in a heterozygous state they may confer a phenotype more severe than that of β thalassemia trait and lead to a clinical syndrome of thalassemia intermedia and its associated complications such as extramedullary hemopoiesis, bone disease, endocrinopathies and iron overload even in the absence of transfusion. In this report we present a case of double heterozygosity for HbC and β thalassemia dominant leading to a series of complications that were treated successfully once the correct diagnosis was made.

Vehicles sold in the United States and Europe are equipped with a specific set of legal diagnostics, called on-board diagnostics; these are used to monitor the performance of various elements of the emission control system. The driver is informed of any failures by the use of a Check Engine Light on the dashboard of the vehicle and then should return the vehicle to the dealership for rectification. The vehicle manufacturer’s aim is to ensure that the Check Engine Light is only illuminated for legitimate failures. For the calibration of an on-board diagnostics, there needs to be sufficient separation between the response of a good sensor and a failed sensor; the setting of this threshold should be based upon a statistical model of the data so that the predicted failures rate can then be determined. An additional benefit of obtaining a statistical model is that it allows confidence limits to be applied to the data; this then gives the engineer the ability to determine the trade-off between the number of data points and the confidence in the estimated statistical model.

Objective To evaluate the clinical reliability of narrow implants placed in a one-stage procedure and early loaded in the upper and lower incisor region. Material and methods This is a prospective, single-arm, multicenter study in which patients with missing natural dentition in upper lateral and lower incisor positions were enrolled. Eligible implants (OsseoSpeed™ TX 3.0S, DENTSPLY Implants) were of three different lengths and of 3.0 mm in diameter. One-stage surgery was performed and healing abutment connection took place. Placement of the permanent single crown took place after a 6-10 weeks healing period. Clinical and radiographic checks were performed at implant placement, loading, and at the 6, 12, 24, and 36 months follow-up visits. Results A total of 69 subjects with 97 implants have been included in this study. From surgery to 36 months follow-up, 5.6% of the implants showed bone loss of more than 1 mm, while no bone loss at all were observed for 57.3% of the implants. The mean marginal bone level change from surgery to the 6, 12, and 36 months follow-up visits was -0.27, -0.11, and -0.09 mm, respectively. The total survival rate after 3 years is 95.5%. Conclusions The data presented show stable marginal bone levels as well as healthy soft tissue around OsseoSpeed™ TX 3.0S implants, after 3 years of function. An interesting finding from this investigation was that a longer healing period before crown placement and loading contributed to statistically significant less marginal bone loss between loading and the 1-year follow-up visit (Galindo-Moreno et al. 2012). This finding, associated with a stable probing pocket depth and a stable crown-gingiva distance, using a one-stage surgical procedure helps to maintain the integrity of the peri-implant soft tissues. Narrow implants can be considered as a valid solution in the treatment of the localized narrow bony defects in the anterior area with reduced spaces between the natural teeth.

For PAM4 transmission in 400 Gb/s Datacom networks, use of equalization and FEC, and a need to reduce cost, force a replacement of historic eye-mask and TDP tests. We describe that replacement: TDECQ.

This article presents a minimal parameter vehicle simulation model to predict the vertical suspension loads expected during abusive driving manoeuvres, such as a kerb strike event. Impulsive suspension loads are applied to tyre and suspension elements under such conditions. In particular, the aim is to specifically study the reactions of jounce bumper–rebound stop and tyre characteristics. For this purpose, a vehicle in-plane pitch dynamics model with 7 degrees of freedom suffices. Non-linear and hysteretic characteristics of the bump-stop elements are included through a new parametric map concept, based on displacement and velocity-dependent hysteresis. Furthermore, a static tyre model is described, tailored to predict the radial stiffness against penetration of an edge with a flat-type rigid body geometry. The tyre model is derived on the basis of classical membrane theory and represented in terms of only a few input parameters. Model validation is supported through experiments at both component and system levels.

Traumatic brain injury (TBI) is currently a major cause of morbidity and poor quality of life in Western society, with an estimate of 2.5 million people affected per year in Europe, indicating the need for advances in TBI treatment. Within the first 24 h after TBI, several inflammatory response factors become upregulated, including the lectin galectin-3. In this study, using a controlled cortical impact (CCI) model of head injury, we show a large increase in the expression of galectin-3 in microglia and also an increase in the released form of galectin-3 in the cerebrospinal fluid (CSF) 24 h after head injury. We report that galectin-3 can bind to TLR-4, and that administration of a neutralizing antibody against galectin-3 decreases the expression of IL-1β, IL-6, TNFα and NOS2 and promotes neuroprotection in the cortical and hippocampal cell populations after head injury. Long-term analysis demonstrated a significant neuroprotection in the cortical region in the galectin-3 knockout animals in response to TBI. These results suggest that following head trauma, released galectin-3 may act as an alarmin, binding, among other proteins, to TLR-4 and promoting inflammation and neuronal loss. Taking all together, galectin-3 emerges as a clinically relevant target for TBI therapy., A.C.-J. is supported by a pre-doctoral fellowship from Spanish Ministerio de Educación, Cultura y Deporte. This work has been supported by grants from the Spanish Ministerio SAF2015–64171R (MINECO/FEDER, UE), Blizard Research Theme grants, Blizard Institute, Queen Mary University of London. M.A.B has been funded by the Barts Charity Centre for Trauma Sciences (C4TS) and the Wellcome Trust Institutional Strategic Support Fund (ISSF).

This article provides solution for isothermal mixed hydrodynamic conjunction of the compression ring to cylinder liner. This is obtained using the average flow model representation of Reynolds equation based on pressure- and shear-induced flow factors. In particular, the effects of compression ring axial profile along its face-width and surface topography of contiguous solids are investigated. It is shown that ring geometry may be optimized to improve lubrication, whilst care should be taken in order to avoid oil loss or degradation resulting from any loss of sealing. In predicting friction, it is shown that appropriate surface parameters should be used in-line with the state of wear of the ring. For a new ring against a plateau honed liner, boundary friction contribution during the initial running-in wear phase should be predicted according to the average asperity peak heights protruding above the plateau, whilst the plateau height also takes into account the valleys within the surface roughness or grooves created by any cross-hatch honing would be the appropriate measure of topography for worn rings. The main contributions of the article are in providing an analytic solution as well investigation of ring face-width geometry and effect of wear upon friction. However, it is acknowledged that generated heat, inlet boundary starvation and circumferential non-conformity of ring to the bore surface would affect the film thickness and exacerbate generated friction accordingly. These further considerations would require a numerical solution, rather than an analytical one presented here.

Objectives: The Latarjet procedure for autograft transposition of coracoid to the anterior rim of the glenoid remains the most common procedure for reconstruction of the glenoid after shoulder instability. The anatomic glenoid reconstruction using distal tibial allograft has gained popularity and is suggested to better match the normal glenoid size and shape. However, there is concern for decreased healing and increased resorption using an allograft bone. The purpose of this study was to evaluate the arthroscopic reconstruction of the glenoid with respect to the size, shape, healing, and resorption of autograft coracoid vs allograft distal tibia. Methods: A retrospective review of 50 consecutive patients who had an arthroscopic boney reconstruction of the glenoid (13 coracoid; 37 distal tibial), diagnosed with anterior shoulder instability, and CT confirmed glenoid bone loss >20%. Pre-and post-operative CT scans were reviewed by two fellowship trained musculoskeletal radiologists for: graft position, glenoid concavity, cross sectional area, width, version, total area, osseous union, and graft resorption. Results: Graft nonunion was seen in 3 (23.07%) of the coracoid patients, and in 2 (5.4%) of the tibial allograft patients (OR 5.25; 95% CI: 0.768-35.89). Odds ratios comparing allograft to coracoid for overall resorption was 5.00 (CI: 1.276-19.597). Graft resorption greater than 50% was seen in 3 (8.11%) of the allografts and was absent within the coracoid patients. Graft resorption lesser than 50% was greater in both groups with 27 (72.97%) allograft and 6 (46.15%) coracoid patients. However, no statistically significant difference was found between the two procedures regarding AP diameter of graft (p=0.818) or graft cross sectional area (p=0.797). Conclusion: Arthroscopic anatomic glenoid reconstruction using distal tibial allograft showed greater boney union but higher resorption compared to coracoid autograft. Even so, there was no statistically significant difference between the two procedures regarding final graft surface area and size of grafts. These short-term results suggest distal tibial allograft as an alternative to coracoid autograft in the recreation of glenoid boney morphology.

Transient tyre characteristics can have significant influence in vehicle handling, particularly in anti-lock braking system (ABS), which involves wheel speed oscillations as a result of rapid changes in wheel brake pressure. Hitherto, ABS studies have been conducted mostly with straight-line motion. Relatively simple vehicle models have been used which cannot capture the interactions between non-linear handling dynamics and tyre behaviour. This article takes such interactions into account, using a non-linear 14-degrees-of-freedom vehicle model in combination with three different single-point contact tyre models with transient characteristics. They include a stretched-string-based model, a modified stretched-string model, and a contact mass model. The particularly demanding situation of combined cornering/ABS braking is investigated. It is shown that although all tyre models are of similar bandwidth (maximum frequency ≈ 15 Hz), the simple string tyre model fails to cope with the non-linearities involved in combined braking/cornering and predicts greater braking distances than the two more enhanced tyre models.

The short-term-Fourier-transform (STFT) is used to identify different sources of IC engine-block vibration from single-point acceleration measurements taken with a commercial knock sensor. Interest is focused on using the STFT to distinguish normal combustion from other sources of excitation including valve impact, injector pulses, and abnormal combustion, such as knocking. Positive identification of these other events using a single method can be useful for pre-processing of measured knock-sensor data for neural-network-based reconstruction of cylinder pressure. It can also be useful separately as part of a fast knock detection system. A series of experiments is discussed to create the data to isolate these different events on a 3-cylinder gasoline engine. In each case, the measured data is processed using the STFT to attempt to isolate the occurrence of particular events in the time domain. Four classes of experiments are undertaken: (i) an un-fired (motored) engine, driven by a dynamometer, with spark plugs fitted, and then removed, to isolate valve impact; (ii) a fired engine running under idle conditions, to contrast no-load combustion with no combustion; (iii) a part-loaded engine running normally, and then running with one injector switched-off, and (iv) a fully-loaded engine running normally, and then running with knock-control switched-off. The paper shows that a single Time-frequency analysis method, applied to knock sensor data in the form of an appropriately-tuned STFT, can effectively identify the occurrence of these events in the time domain if responses are adequately separated and strong enough.

The paper will discuss progress towards a new characterisation of architecture based on the activities of the recently formed INCOSE UK Chapter Architecture Working Group. The focus of the paper will be on describing the diversity of opinion we have observed in discussions of the fundamental characteristics of architecture and progress towards resolving the various conflicts that arise. We have made progress in refining the definition of architecture, the understanding of the role of patterns within architecting and how the conceptual underpinnings of architecture may be made consistent with the uses and types of architecture.

A NARX neural network is adapted for cylinder pressure trace reconstruction on a multicylinder engine. Following a systematic study to establish the required NARX input information (using measured pressure traces and simulated crank kinematics), two fully recurrent training algorithms are developed and applied to real engine data. These include a back-propagation-through-time algorithm (BPTT) and an extended Kalman filter (EKF). For multi-cylinder engines, two cases are examined, both assuming crank kinematics is obtained from a single shaft-encoder fitted at the forward end of the crankshaft. In one case, a NARX model is constructed to provide an inverse relationship between the kinematics at the encoder location and the pressure trace in an arbitrary cylinder. In the second case, by transforming the kinematics (to emulate a local encoder), a different NARX model is constructed to relate the kinematics at the crank location of a particular cylinder to the corresponding pressure trace. The accuracy and efficiency of both NARX models is examined for application to a three-cylinder in-line DISI engine (in which pressure traces are measured on all cylinders). The paper shows that the computational requirements of training are substantial and, although the efficiency of the EKF algorithm is better than the BPTT, the fitting accuracies are similarly good. For generalization, however (to unseen data), neither method is yet sufficiently accurate (even for steady state engine operation) unless substantially more training data are used to achieve the target accuracy of ± 4 per cent. The overall conclusion of the paper is that the NARX model has the correct architecture for multicylinder pressure reconstruction.

This paper investigates vehicle dynamic response for the increasingly common manoeuvre over single speed bumps, which is a non-trivial complex motion. One major aim of the study is to investigate the effect of the anti-roll bar upon vehicle body dynamics, while negotiating such traffic calming features. Numerical predictions are made with an intermediate vehicle model, whose results conform well to the actual vehicle tests. These results seem to suggest that events caused by truncated speed bumps can have implications for design of anti-roll bars from a ride comfort viewpoint, over and above the usual requirements dictated by safe vehicle handling.

The paper attempts to provide an integrated framework for the objective assessment of the transient handling responses of non-linear vehicles. The ultimate aim of the proposed framework is the characterization of such responses as neutral or under/over-steering. A new methodology is employed, which has previously been applied for the classification of the transient response of linear vehicles. The success of the proposed method is judged based on its robustness, the consistency of the results, and their practical implications. Furthermore, the results are compared with the findings of traditional approaches for the characterization of the steady-state and transient handling behaviour. The corresponding discussion reveals the agreement between the approaches, but also highlights the slightly different definition of the neutrally steering vehicle, as perceived by the proposed method.

Minimization of parasitic losses in the internal combustion (IC) engine is essential for improved fuel efficiency and reduced emissions. Surface texturing has emerged as a method palliating these losses in instances where thin lubricant films lead to mixed or boundary regimes of lubrication. Such thin films are prevalent in contact of compression ring to cylinder liner at piston motion reversals because of momentary cessation of entraining motion. The paper provides combined solution of Reynolds equation, boundary interactions, and a gas flow model to predict the tribological conditions, particularly at piston reversals. This model is then validated against measurements using a floating liner for determination of in situ friction of an engine under motored condition. Very good agreement is obtained. The validated model is then used to ascertain the effect of surface texturing of the liner surface during reversals. Therefore, the paper is a combined study of numerical predictions and the effect of surface texturing. The predictions show that some marginal gains in engine performance can be expected with laser textured chevron features of shallow depth under certain operating conditions.

BACKGROUND: Spinal cord tumors can be classified as intramedullary, intradural extramedullary, or extradural. The differential diagnosis of spinal cord tumors includes meningiomas, astrocytomas, ependymomas, metastasis, nerve sheath tumors such as schwannomas or neurofibromas, and multiple sclerosis plaques. Radiology can provide clues to the type of tumor, but a pathology evaluation of a specimen is necessary to provide an accurate diagnosis. These tumors can cause a variety of neurological symptoms from spinal cord compression including pain, weakness, and paresthesia. They are treated by surgical resection, with a variety of outcomes possible depending on the severity of the preoperative symptoms, location and extent of the tumor, and efficacy of the surgery performed. CASE DESCRIPTION: A 59-year-old male from Vietnam came to the Atlanta Medical Center for evaluation of severe ride sided hemiparesis and paresthesias. He first noticed alterations in his handwriting and quickly deteriorated to the point of being unable to walk or move his right arm. A cervical spinal mass was identified and analyzed on magnetic resonance imaging. Surgical resection was performed under a microscope in a joint operation between an orthopedic surgeon and neurosurgeon. A specimen of the tumor was sent to pathology for further evaluation. CONCLUSION: The mass was determined to be an intradural extramedullary schwannoma. The severity of the patient's symptoms and the location and size of the tumor made full recovery unlikely and postoperative quadriplegia a real possibility. The tumor was surgically resected, which led surprisingly, however, to a full and prompt resolution of the patient's symptoms. Less than 2 weeks after surgery, the patient was able to walk and had almost fully regained use of his hands.

OsteoArthritis is a debilitating disease throughout the developed world, causing significant loss of quality of life to individuals and damaging economies, the imaging system described in this paper has the potential to provide an objective means of measuring and reporting lesion dimensions and providing a machine readable data archive for future study. Existing imaging methodologies have been reviewed and contrasted and despite certain limitations the optical method proposed has the potential to address the issues highlighted to date. The preliminary depth measurement results with an accuracy of 200 µm±6% suggests a potential system for the objective reporting of tissue degradation. It is also envisaged that the bio tribological performance may be inferred from the tissue surface condition as image by the proposed system.

The paper describes the importance of reducing frictional losses in internal combustion (IC) engines, thereby improving engine efficiency. One of the main sources contributing significantly to engine friction is the interaction between the piston compression and oil rings and the cylinder bore/liner. Improving the tribological performance in these conjunctions has the greatest potential for performance improvement in the IC engine. Traditionally, the approaches used to tackle this problem have relied heavily on empirical engineering judgement. These have resulted in many inconclusive studies, involving a large number of alternatives, including the introduction of cylinder liners with surface modification work and/or with special coatings. This paper highlights a fundamental investigation of surface modification and coating and its impact on frictional performance. The study combines numerical and experimental approaches. Very good agreement is found between the conclusions of numerical predictions and those of engine test bed work.

This clinical report describes an unusual consequence of peri-implantitis and subsequent implant failure in a 72-year-old man. Following uneventful implant removal, osteomyelitis developed at the implant site, which subsequently weakened the mandible sufficiently for a pathological fracture to occur. The patient was treated successfully by use of an intensive oral hygiene regime, antibiotics, and conservative management. The consequences and management of implant failure are discussed, as well as issues relating to the management of osteomyelitis and pathological bone fracture.

An analysis of the mechanism of tyre contact force generation under transient conditions is presented. For this purpose, two different versions of a brush model are used, both with inertial and viscoelastic properties. The first model consists of independent bristles, while the second, with a more realistic scenario, introduces viscoelastic circumferential connections between the sequential bristles, which affect the lateral degrees of freedom. Friction between the tyre and the ground follows an experimentally verified stick-slip law. For the model with independent bristles, the state of each bristle at any instant of time depends only on the state of the same bristle at a previous time step. In the second model, the instantaneous state depends on the state of the same bristle at the preceding time step, as well as on the state of the two adjacent bristles at the same time. Simulation results reveal the differences between the two models and most importantly show how transient friction force generation may differ substantially from steady state predictions. The findings suggest that transient tyre behaviour should not be attributed solely to the contributions of the flexible belt and carcass. On the contrary, the observed transience in the neighbourhood of the contact patch should also be taken into account.

Enterprise architecture is the discipline of describing and analysing the relationship between an enterprise's objectives and purpose, and the system of systems which the enterprise uses to help achieve those objectives. This paper makes the case for the importance of aesthetics in enterprise architecture. It proposes an enterprise architectural modelling language which addresses enterprise form, purpose and aesthetics. This language is a meta-model extension of SysML which uses the power of SysML to address the engineering aesthetic of enterprise architecture. The paper is based on work carried out for the UK Ministry of Defence's Integration Authority to develop an “Integration Services Support Environment” (ISSE). ISSE uses the enterprise architecture modelling language to enable the consistent description, and hence analysis, of a large and heterogeneous system of systems. ISSE itself has been developed as a enterprise architecture modelling tool and as a repository of interconnected models of MoD's enterprise.

The behaviour of tyres under transient handling manoeuvres is studied with the aid of a newly developed model. The model consists of a discretized flexible belt with damping and inertia, connected to the rim by viscoelastic elements representing the carcass. In the neighbourhood of the contact patch, the belt is connected to a separate discretized viscoelastic tread with inertia. A separate algorithm taking into account the radial deflection of the carcass elements is used for the calculation of the contact pressure distribution along the contact patch. Friction follows a stick—slip law taking into consideration the velocity of tread elements, the normal force and the unequal coefficients of friction in the lateral and longitudinal directions. The model seems capable of generating transient forces and moments including the phase lags observed under time-varying kinematic excitations.

The paper presents a six-degree-of-freedom (6-DOF) multi-body vehicle model, including realistic representation of suspension kinematics. The suspension system comprises anti-squat and anti-dive element. The vehicle model is employed to study the effect of these features upon combined bounce and pitch plane dynamics of the vehicle, when subjected to bump riding events. The investigations are concerned with a real vehicle and the numerical predictions show reasonable agreement with measurements obtained on an instrumented vehicle under the same manoeurves.

Prevention of excessive tooth wear should form the basis of any ongoing lifelong dental management. In some situations, however, it may also become necessary to consider interventive restorative treatment in order to protect vulnerable tooth surfaces and re-establish satisfactory appearance and function. A wide range of treatment options currently exist when considering the restoration of the worn dentition ranging from the more conventional fixed and removable prosthodontic approach to some of the newer, less invasive and minimal preparation adhesive techniques. This chapter illustrates and discusses the treatment options now available to the dental surgeon when restoring the worn dentition. While a number of the minimal preparation adhesive methods would appear to offer significant advantages over more traditional measures, only time and careful clinical evaluation will dictate if these become the accepted treatment patterns of tomorrow.

Traditional training teaches specific skills and concepts often in a series of discrete and ultimately disjointed processes. Coaching, on the other hand, is an open‐ended process that analyses the present situation, defines the performance goal, combines personal, organizational and external resources and then implements a plan for achieving that goal. Following this definition, the article considers the coaching process in detail, and the role of the coach, particularly how members of the team make use of him or her. It develops two models for coaching to deal with different circumstances and illustrates their use with case studies. A “coaching culture” within the organization can also help generate a forum for creativity, planning and problem solving.

The main function of piston compression ring is to seal the space between the piston and the liner, acting as slider bearing, subjected to reciprocating motion. The compression ring-cylinder liner conjunction has been extensively studied and it is responsible for a significant part of the total frictional parasitic power losses of an engine. Paradoxically, the required sealing function of the compressions ring can result in increased friction. Therefore, in order to improve engine efficiency, it is important to fundamentally understand and subsequently palliate some of these losses. Another problem in any slider bearing-type contact is lubricant film rupture and cavitation in the conjunctional outlet zone, reducing load carrying capacity and potentially leading to erosion damage. A cavitation model presented in two-phase flow CFD analysis of the ring-bore contact under isothermal conditions. Liquid flow is modelled as a continuous phase and a dispersed phase, representing cavitation bubbles. Many of the fundamental physical processes assumed to take place in cavitating flows are incorporated into the model.

Objectives: The treatment of displaced clavicle shaft fractures has evolved due to complications experienced by conservatively treated patients. Numerous operative modalities are available with various positive and negative aspects associated with each technique. This prospective randomized controlled trial compares the outcome of patients treated operatively with a novel locked intramedullary device and patients treated by traditional anatomically contoured locked plating. Methods: Patients with displaced and shortened clavicle shaft fractures were randomized according to presentation into 2 groups - intramedullary fixation and anatomically contoured locked plating. All patients were operated by the same surgeon with similar post-operative regimes for both groups. Outcomes accessed were DASH and Constant Shoulder scores at 6 weeks, 3 months and 6 months, scar size and quality, operative time, union rate and incidence of supraclavicular nerve injury at the time of surgery. Patients were assessed by the operative surgeon, a physiotherapist and an occupational therapist. Progression to union was assessed by a radiologist. Results: 40 patients with 6 months follow-up were available for review - 20 in each group. No statistically significant difference in average DASH and Constant Shoulder scores at 6 weeks, 3 months and 6 months for the two groups were found. The surgical scars were smaller and the cosmetic result better in the intramedullary group. Operative time was significantly shorter in the intramedullary group. Both groups achieved a 100% union rate at 6 months post-op. The rate of supraclavicular nerve injury in the plating group was higher and most patients complained of prominent hardware. Conclusion: Locked intramedullary fixation of clavicle shaft fractures using the Sonoma CrX system was found to be a reliable method of achieving fracture reduction and fracture union. Shoulder function was restored and union achieved with a good cosmetic result. Supraclavicular nerve injury is rare and a second operation to remove prominent hardware is not necessary. Patient outcomes were found to be similar to that achieved by anatomically contoured locked plating - the current accepted gold standard method of treatment.

Observes that the provision of intelligent control is seen as the logical extension of existing seat‐belt and airbag systems for passenger vehicles to optimize secondary safety performance. Demonstrates the need for discrete information about the driver/passenger in the vehicle in order to provide optimal control of seat‐belt pre‐tensioning; seat‐belt reel‐out (post‐crash pulse); and air bag inflation timing and/or rate. Finds, from system modelling and statistical crash data, that such information as occupant mass and position with respect to vehicle interior and steering wheel are important parameters in the optimal control of the above integrated systems. Justifies these needs and shows that the design of a Smart Seat provides the necessary data. Explains that the design incorporates sensor systems, using a Mechatronic integrated approach.

Changes in the consumer market have resulted in many companies allocating considerable resources to their logos and trademarks with a subsequent need for high quality product packaging. Looks at design work undertaken for a system for quality control of printing images on packaging materials. Discusses the need to integrate the print process within the box making machine and the challenge of designing print machinery that can utilise environmentally friendly recycled paper. It looks at the problems of sensing and data acquisition from high through put machines and describes the two main aspects of print quality ‐colour quality and print registration and the methods of gathering this information. Concludes that a mechatronic approach is required for quality control of print images on packaging materials with an end product comprising sensors, machine vision, microprocessors and ultimately machine control and actuation.

This Vehicles sold in the US and Europe have to be equipped with a Diagnostics, called On-Board Diagnostics (OBD), which monitor the performance of various elements of the emission control system. The driver is informed as to any failures by the use of a Check Engine Light on the dashboard of the vehicle and then should return the vehicle to the dealership for rectification. The vehicle manufacturer's aim is to ensure that the Check Engine Light is only illuminated for legitimate failures. For the calibration of an On Board Diagnostics there needs to be sufficient separation between the response of a good sensor and a failed sensor, the setting of this threshold should be based upon a statistical model of the data so that the predicted failures rate can then be determined. By applying confidence limits to the models allows the engineer to understand how additional data points will effect the calculation of the failure threshold. This gives the engineer the ability to determine the tradeoff between the number of data points and a confidence in the estimated statistical model.

College students with undiagnosed attention-deficit/hyperactivity disorder (ADHD) exhibit varying symptoms and may have trouble in class, be involved in driving accidents, be late to appointments, be disruptive, and abuse alcohol. Clinicians and others in a position to recognize and identify behaviors indicative of ADHD should either complete a thorough assessment for ADHD, including disorders that commonly co-occur with or are mistaken for the illness, or refer students to someone who can. For students with a comprehensive evaluation who are diagnosed with ADHD, special accommodations are available on campus. Clinicians can provide students with several strategies to manage their disorder and improve their chances of having a successful academic career.

The regime of lubrication changes in a transient manner in many load bearing conjunctions. This is particularly true of any conjunction which is subjected to changes in contact kinematics as the result of stop-start or motion reversals and loading. One such conjunction in the IC engine is the piston-bore contact. A repercussion of these transient events under otherwise perceived steady operating condition is the underlying changes in the mechanisms giving rise to engine efficiency, such as parasitic losses, mainly due to friction. Understanding the nature of these losses is the prelude to any form of palliation. A single cylinder motocross motorbike engine’s cylinder barrel is redesigned to accept wet liners with various incorporated instrumentation. The paper describes one such barrel which incorporates an instrumented floating liner for the purpose of measurement of in-cylinder friction. The principle and design of the floating liner is described. A series of tests are carried out in order to ensure the operational integrity and repeatability of the device. The basic test includes motorised running of the engine without the cylinder head installed. This renders simplified motion of the liner, subject to resistance by friction only. In a sense, under this type of motion, the liner should undergo a form of simple harmonic motion, which is verified using a number of suitably positioned accelerometers. Some more representative tests are reported under motorised conditions with the cylinder head installed. Thus, the effect of chamber pressure is introduced. However, with no combustion pressure, heat output and resulting side forces, a better understanding of tribological conditions is accrued owing to the reduced physical interactions. The results show the dominance of a mixed regime of lubrication at the dead centre reversals.

Both the piston ring and cylinder bore experience wear throughout their life cycle. Therefore change occurs in the geometrical profile and topography of the ring. In addition, coating on the ring is also subject to wear, thus altering the physical/mechanical property of the contacting surface. These changes affect the tribological performance of the ring-bore conjunction. Geometrical changes often alter the ring contacting profile, which affects the entrainment of the lubricant into the conjunction. This can affect the regime of lubrication, thus mechanisms that contribute to friction. Wear of surfaces also plays some role in boundary friction in terms of topographical changes as well as surface properties such as hardness and asperity shear strength. Most analysis does not take into account changes in tribological conditions which occur as the result of these salient changes in practice. The paper intends to bridge this gap in the fundamental knowledge and provide explanations for some in-field experiences noted with wear of a compression ring in a typical engine test. The method of solution used is based on the average flow factors which are indicative of entrainment of the lubricant through the rough ring-bore conjunction. This approach was initiated by Patir and Cheng, for which realistic topographical parameters according to the stage of the wear process is included. Changes in friction and fuel energy consumed are predicted.

A study is presented of the optimal crossover duct location and width to obtain consistent branched detonation transition from one detonation tube to another. On a Pulsed Detonation Engine (PDE) with detonation branching, the duct location at which the detonation crosses from one (primary) tube to a branched (secondary) tube impacts the number of successful detonations. In this paper, a comparison is made of the effects of the location and width of the crossover duct for hydrogen, ethylene and an n-alkane. The crossover location is varied from the aft end of the detonation tube to the middle of the detonation tube while the crossover width is varied from 2.5 in to 0.5 in. Detonation wave speeds are measured and compared to Chapman-Jouguet velocities in order to determine successful detonations. Regardless of crossover location, all three fuels are demonstrated 100% of the time to transition between 2 in detonation tubes with a crossover width of 2 in. With a mid-location crossover duct, all three fuels are demonstrated 100% of the time to transition detonations between 2 in detonation tubes with a crossover width between 1.75 in and 2.5 in.

Form validation is an integral part of a web application. Web developers must ensure that data input by the user is validated for correctness. Given the importance of form validation it must be considered as part of a model-driven solution to web development. Existing model-driven approaches typically have not addressed form validation as part of the model. In this paper, we present an approach that allows validation constraints to be captured within a model using UML and OCL. Our approach covers three common types of validation: single element, multiple element, and entity association. We provide an example to illustrate an architecture-centric approach.

To be adopted by architects, modelling approaches must provide a means to leverage the software patterns and architectural styles that are relevant to development practice, instead of those proscribed by black-box CASE tools. Architecture-Centric Model-Driven Software Development (AC-MDSD) is a modelling approach that provides architectural control of the generated application. However, AC-MDSD primarily focuses on generating infrastructure code. We apply AC-MDSD to web engineering and contribute a technique to define and generate system behaviour that goes beyond the create/read/update/delete infrastructure functionality. We use UML profiles augmented with OCL to specify the behaviour. We provide an example to illustrate the approach and outcomes.

A device is described for use in confirming the energy constancy of clinical electron beams. A wedge shaped absorber is placed over an ionization chamber leading to an energy dependent response. A measurement under the energy filter is divided by a measurement in air to correct for the inherent energy dependence of the chamber. A nearly linear response is demonstrated. PACS number(s): 87.52.–g, 87.53.–j, 87.66.–a

Architecting has become an important discipline within the broader context of systems engineering. The lack of a common understanding of the discipline amongst practitioners and other stakeholders, particularly in broad communities, can result in confusion, misunderstanding and inefficiencies. Methods and principles from the Soft Systems Methodology (SSM) are used to define a method for investigating different approaches to systems and system of systems architecting, which we characterize as distinct ‘belief systems’. This method is applied to a number of such ‘belief systems’ encountered in applied systems architecting with the aim of clarifying their key features and promoting mutual understanding across different architecting communities.

This paper presents the video retrieval engine VERGE, which combines indexing, analysis and retrieval techniques in various modalities (i.e. textual, visual and concept search). The functionalities of the search engine are demonstrated through the supported user interaction modes.