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The effectiveness of nonlinear filters depends on many factors, but one of the most important is how accurately the filter is able to predict the state dynamics of the underlying system between measurements. For a wide class of Gaussian white noise driven nonlinear systems the Bayesian optimal prior can be obtained by solving the system’s corresponding Fokker–Planck Equation (FPE). Unfortunately the Fokker–Planck Equation is a partial differential equation with dimension equal to the number of states in the underlying dynamical system, making it extremely difficult to solve for realistic systems due to Curse of Dimensionality scaling issues. As a result it has been and still largely remains computationally impractical to simulate higher dimensional Fokker–Planck equations, at least while obtaining very high accuracy across the entire transient probability density function. This paper presents a general nonlinear filter based on solving the transient Fokker–Planck equation via Smooth Particle Hydrodynamics (SPH) at lower resolution, which turns out to still allow for accurate state estimation. The filter is enabled by an efficient heuristic resampling scheme of the SPH solution also presented here. The FPE-SPH Filter is able to replicate the accuracy of the Particle Filter and Extended Kalman filter (EKF) for lower-dimensional systems, while also being more robust than the EKF on certain classes of system.

Maternal nutrition impacts fetal development, and may play a role in determining resilience to stress and vulnerability to stress-precipitated psychiatric disorders, such as anxiety and depression. In this study, we examined the effect of a reduction in maternal dietary protein during pregnancy on the brain neurochemistry and behavior of offspring. We focused specifically on the serotonin system, the 5-HT1A receptor and the responsivity of offspring as adults to stress. Dams were fed either a low protein diet (10% protein by weight) or isocaloric control diet (20% protein by weight). The low protein diet did not alter maternal food intake and body weight, or litter size and the average birth weight of male or female littermates. 5-HT1A receptor function, as measured by quantitative autoradiography of 8-OH-DPAT (1 μM)-stimulated [35S]GTPγS binding, was markedly reduced in hippocampus of weanling female, but not male offspring (postnatal day, PND 21) of dams fed the low protein diet. The number of serotonergic cell bodies in the rostral raphe, and 5-HT metabolism in the limbic system of weanling offspring was not altered by maternal low protein diet. The deficit in hippocampal 5-HT1A receptor function observed in weanling female offspring persisted into adulthood (PND 112), and was accompanied by an increased sensitivity to stress, specifically increased immobility during a 15-minute forced swim challenge and increased anorexia following 30-minute restraint (PND 97-100). The present work begins to uncover important future directions for understanding the early developmental origins of resilience to stress, and factors that may put individuals at greater risk for stress-related psychiatric disorders.

Variations in local processing parameters and conditions in additively manufactured materials make mechanical properties difficult to characterize. Microtensile testing is providing a wealth of information on these local property variations. Here we utilize spatial autocorrelation techniques to show autocorrelation of grain sizes and mechanical properties with build height in a specially-designed, additively manufactured AlSi10Mg part. This result suggests that, at least in some cases, an interplay between local part geometry and the fabrication process occurs that affects local mechanical properties.

There is an increasing phenomenon of competing class actions – class actions purporting to cover the same or nearly the same common issues of alleged wrongdoing but brought by different representative parties (or “lead applicants”) with different lawyers and often different litigation funders. A decision by a court allowing one class action to proceed (with, presumably, one set of lawyers acting) while staying all others is significant and raises a number of matters that deserve consideration. Court and economic efficiency are key among these though they can point to two answers. Efficiency can be produced by economies of scale and lack of duplication (favoring one proceeding) but also by rivalrous competition (favoring more than one proceeding). If litigation has attributes of 'natural monopoly' then efficient franchise bidding through the former may be the preferred solution for trying the common issues stage, though not necessarily the second stage of trying individual issues.

While use of large heads in total hip arthroplasty (THA) continues to grow, concerns have been raised regarding anterior hip pain resulting from impingement of the prosthetic head against soft-tissues like the iliopsoas. To address these concerns, a new anatomically contoured head (ACH) was developed. In this study cadaver tests were utilized to show that iliopsoas impingement/tenting caused by conventional heads is significantly relieved with the more rounded and reduced distal profile of the ACH. Thus, the ACH implant may be able to decrease the risk of soft-tissue impingement with conventional heads, particularly in the smaller hip.

The question of creating an Australian head of state is a symbolic, constitutional and governance issue that remains unresolved. The lesson of the 1999 referendum is that for the current constitutional arrangements to be modified, there will need to be some consensus on a model. Yet at present the movement is deadlocked between a direct election model and a parliamentary appointment model with substantively different implications. There is therefore a great challenge to create a model that satisfies both the desire for popular electoral input and the desire to retain an essentially ceremonial and politically neutral non-executive head of state. After reviewing extant models (including relevant overseas models) and historical and conceptual issues, the problems of a full popular vote are discussed. The article then responds by introducing new concepts to the debate. These are: (1) “Tri-partisan Endorsement” (or “Three-way Support”) being a three party endorsement of a single candidate to face the voters along with any other nominees in an open popular election; (2) “Fifty-Fifty” being a method for appointment of an Australian head of state which involves aggregating the results of a parliamentary and a popular vote. The first seeks to achieve a politically neutral candidate while the second seeks to moderate the parliamentary vote for such head of state with a popular vote and vice-versa. The two concepts are separate but might also be utilised in combination in a single model. Finally, the article proposes a partial response to the unresolved “1975” dilemma through “Concurrent Expiration” where a head of state who removes a Prime Minister against the will of the House of Representatives will see the former’s own tenure expire 75 days after the holding of the ensuing election (subject to possible re-election). The article concludes that such concepts offer hope for the development of a judicious consensus model capable of achieving the support of the Australian people at a referendum.

The bats used in Major League Baseball (MLB) are required to be turned from a single piece of wood. Northern white ash had been the wood of choice until the introduction of hard maple in the late 1990s. Since the introduction of maple to the game, there was a perceived increase in the rate of bats to exhibit multiple piece failures (MPF)—both ash and maple. These failures introduced a new aspect to the game that can be a significant factor during play, i.e. pieces of bats going into the field of play, thereby distracting fielders while reacting to the batted ball. Observations of bat breakage in the field and lab testing of bats in controlled conditions have shown the bat durability is a function of wood quality and bat profile. Wood quality is described by the density and the slope of grain of the wood used in the bat. The density and the slope of grain determine the effective strength of the wood. The bat profile is described by the variation in the diameter of the bat along its length. The wood densities and bat profiles which are preferred by players, are typically in direct contradiction with what makes for a durable bat. In this paper, the finite element method is used to develop calibrated models of the breaking of wood bats in controlled lab conditions. The modeling approach is then used to explore how bat profile influences bat durability and what potential changes can be made in bat profile to satisfy player desires while increasing bat durability.

The putting of a golf ball requires control of the speed and direction and an understanding of the interaction between the ball and the putting green by the golfer. The putt can involve a combination of the ball flying over, skidding across, and rolling on the putting green. This study used finite element analysis as a tool to investigate these behaviors, and this paper documents the results for putts with different initial velocities. The finite element analyses were performed in LS-DYNA using a viscoelastic material model for the turf and an elastic material for the golf ball and club head. A high-grade artificial putting turf was characterized by its compressive stiffness in a Universal Testing Machine and displacement of a golf ball resting on turf. The static and dynamic friction between the golf ball and artificial turf were investigated. The ball velocity and deceleration resulting from different putts were examined to help in the characterization of the behavior of the turf. The finite element model will be used in future studies to determine the optimal putter loft and rise angles to achieve consistent putts.

Large-diameter femoral heads are being used increasingly in total hip arthroplasty (THA) to minimize hip dislocation risk. However, recent studies have shown that conventional large heads can impinge on native soft tissues, particularly the iliopsoas, leading to activity-limiting anterior hip pain. To address this, a novel soft-tissue-friendly anatomically contoured femoral head (ACH) was developed. This paper describes the design rationale and pre-clinical testing of the ACH implant. The test results demonstrate that anatomical contouring of large-diameter femoral heads for soft-tissue relief can be accomplished without affecting dislocation resistance, femoroacetabular contact area, or wear performance in ceramic-on-polyethylene implants.

We report on some of the optical properties of Hemoporfin (hematoporphyrin monomethyl ether, HMME), a photodynamic therapy (PDT) photosensitizer that has been in clinical trials in China since the early 1990s. We characterized the photosensitizer on the basis of one- and two-photon absorption and fluorescence emission. The effects of photobleaching were probed to characterize its decay kinetics. Additionally, we determined time resolved fluorescence and thermal effects on fluorescence and absorption properties.

Central venous cannulation is a common procedure in anaesthesia and intensive care. The main indications for central venous catheters (CVCs) are to measure central venous pressure, administer vasoactive or cytotoxic drugs, and for renal replacement therapy. Common sites for catheterization are the internal jugular vein, the subclavian vein and the femoral vein. The internal jugular vein is the most frequently chosen site for insertion of CVCs. Complications occur in up to 10% of central venous cannulations and can be categorized according to mechanical, infectious and thromboembolic aetiologies. The rate of complications depends on a number of factors. These include the site chosen, the condition of the patient, the presence of atypical anatomy and the experience of the operator. The risk of pneumothorax is less common with internal jugular vein placement than with cannulations of the subclavian vein. Carotid artery puncture is uncommon and can be controlled with manual compression. The subclavian route may be preferred for long-term central venous access as there is less patient discomfort post placement and the risk of infection and other long-term complications is lower than at other insertion sites. The femoral route is particularly useful when urgent central venous access is required and the patient is coagulopathic. The femoral route is associated with a high risk of catheter-related infections and venous thrombosis in the long term. In the UK the National Institute for Clinical Excellence (NICE) recommends the use of ultrasonography for the elective insertion of CVCs into the internal jugular veins of adults and children.

This cross-national study of 306 nursing home residents in the United States and the United Kingdom examines the similarities and differences in their evaluation of service quality. Service quality was defined as the differences between expectations about the service and actual perceptions of the service delivered in terms of five dimensions: tangibles, assurance, empathy, reliability and responsiveness. The SERVQUAL instrument was used to measure service quality. The two groups differed in their expectations for quality and their perceptions of service quality: US residents' ratings were lower in all respects.

Purpose : Do tumor cells which survive high dose fractionated irradiation exhibit modified metastasis activity, proliferation kinetics, and/or radiation sensitivity? To address this question experimentally, we have studied three recurrent human tumor xenograft systems. Methods and materials : Three models were derived from a soft tissue sarcoma (HSTS26T), a colon adenocarcinoma (HCT15), and a glioblastoma (HGL21) which had recurred after 90 Gy, 109 Gy, or 77.4 Gy administered in 30 equal doses, respectively. Their production of spontaneous metastasis and cell proliferation characteristics were studied in early generation xenografts in SCID mice, and were compared to those in their previously unirradiated counterparts. As a control, we have also studied each tumor as a post-surgical recurrence. Specimens from the irradiated recurrent and their unirradiated primary tumors were cultured in vitro and their radiation sensitivity determined by clonogenic assay. Results : The three irradiated recurrent tumor systems retained the individual histological features of their unirradiated primary xenografts. A lower metastatic incidence was observed in two of the three irradiated recurrent tumor lines in comparison with their unirradiated control tumors and their surgical recurrent counterparts. No significant differences were found between the irradiated recurrent tumors and their unirradiated counterparts with respect to: volume doubling time, growth time, potential doubling time, mitotic index, PCNA index, and SF 2 values. Conclusions : High dose irradiation given in 30 fractions did not increase the metastatic activity in the three human tumor xenograft systems. Furthermore, the fractionated irradiation did not significantly change their proliferation characteristics and cellular radiation sensitivity.

Purpose: To evaluate the extent of intratumoral heterogeneity of radiation sensitivity in malignant gliomas, by comparing the intrinsic radiation sensitivity of different glioma sublines derived from the same tumor. Methods and Materials: The study was performed on five early established malignant gliomas (passage 3–10). Each specimen was quickly cut into three equal pieces (except for one specimen, where only two pieces were obtained). Each piece was processed independently, disintegrated into single cell suspension using a cocktail of enzymes. Survival curve assays, using colony formation as an end-point, were performed for each subline. Comparison between the intrinsic radiation sensitivity of sublines was calculated using the surviving fraction at 2 Gy and the mean inactivation dose as the measured parameters. The DNA content of the cell lines as well as their cell cycle analysis was determined using flow cytometry. Results: The mean calculated surviving fraction at 2 Gy of all the sublines was 0.37 ± 0.14, the mean mean inactivation dose was 1.98 ± 0.63. The intratumoral coefficient of variation for the calculated surviving fraction at 2 Gy of all cell lines was 38%, while that for intratumoral heterogeneity was 25%. Three of the 5 tumors showed a statistically significant difference in the surviving fraction at 2 Gy and mean inactivation dose values of their sublines ( p Conclusion: There is a significant intratumoral heterogeneity of radiation sensitivity in some malignant gliomas. This heterogeneity may limit the predictive power of surviving fraction at 2 Gy or mean inactivation dose, especially when their values are based upon a single measurement/single biopsy. In the meantime, this heterogeneity may be a factor in the discrepancy between unexpectedly sensitive tumor cell lines in vitro and their high clinical radiation resistance.