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Sternoclavicular joint septic arthritis is rarely seen in the general population. The majority of cases are seen in intravenous drug users. Given the lack of reported cases in the literature, there is no standardized treatment algorithm for this disease. Described treatment methods range from medical management to wide local debridement. The incidence of sternoclavicular joint septic arthritis will likely continue to increase with rising usage of intravenous drugs in the United States. Within the past year, our institution treated four cases.

When designing new optical devices, many simulations must be conducted to determine the optimal design parameters. Therefore, fast and accurate simulations are essential for designing optical devices. In this work, we introduce a deep learning approach that accelerates a simulator solving frequency-domain Maxwell equations. Our model achieves high accuracy while predicting transmittance per wavelength in 2D slit arrays under certain conditions to achieve 160,000 times faster results than the simulator. We generated a dataset using an open-source simulator and compared its performance with those of other machine learning models. Additionally, we propose a new loss function and performance evaluation method for creating better performance models with multiple regression outputs from one input source. We observed that using a loss function that adds binary cross-entropy loss, which predicts whether the differential of the transmittance is positive or negative at wavelengths adjacent to the root mean-squared error of the transmittance value, is more effective for predicting variations in multiple regression outputs. The simulation results show that a four-layer convolutional neural network model demonstrates the best accuracy (R2 score: 0.86). The overall approach presented here is expected to be useful for simulating and designing optical devices.

We provide a comprehensive review of the clinical presentation, imaging evaluation, classification, and management of adolescent idiopathic and adult degenerative scoliosis.

We developed a photoacoustic imaging (PAI) and finite element analysis (FEA) approach for characterizing the biomechanical behaviors of the aqueous veins and perilimbal sclera, and their roles in the regulation of intraocular pressure (IOP). In this study, an optical resolution PAI system captures the 3D architectures of the sclera and the aqueous veins perfused with indocyanine green. FEA computes tissue and vein strain fields. The performance of the PAI-FEA has been validated by tensile test in scleral tissue. The methods have also shown the capability of resolving the strain gradients at the vein-sclera interface during the manipulation of IOP.

We developed a photoacoustic imaging (PAI) and finite element analysis (FEA) approach for characterizing the biomechanical behaviors of the aqueous veins and perilimbal sclera, and their roles in the regulation of intraocular pressure (IOP). 3D architectures of the sclera and the aqueous veins perfused with indocyanine green have been resolved by an optical resolution PAI system. The tissue ans strain fields were quantified using FEA. The performance of the proposed method has been validated by tensile test in scleral tissue. The methods have shown the capability of resolving the strain gradients at the vein-sclera interface during the manipulation of IOP.

The countdown method is a well-known approach to reducing the average length of screening instruments that are presented by computer. In the countdown method, testing is terminated once the result of the screener ("positive" or "negative") has been unambiguously determined from prior answers. Previous research has examined whether presenting dichotomously scored items in order from "least to most frequently endorsed" or "most to least frequently endorsed" is more efficient when the countdown method is used. The current study describes the Mean Score procedure, an extension of the above item ordering procedures to polytomously scored items, and evaluates its efficiency relative to the distribution of other possible item orderings in 2 real-data simulations. Both simulations involve item responses to the Posttraumatic Stress Disorder (PTSD) Checklist for DSM-5 (PCL-5). In the first simulation, items were scored polytomously, and a single cutoff point was used to determine the screening result. In the second simulation, items were converted to dichotomous scores, as well as categorized into 4 clusters; a positive result for the entire assessment was obtained if and only if a positive result was obtained for each cluster. The latter simulation also investigated the effect of reordering the clusters themselves on the efficiency of the countdown method. Results indicated that the Mean Score procedure does not necessarily produce the optimal ordering, but tends to assemble an efficient item ordering relative to the distribution of possible orderings. In the second simulation, reordering the clusters themselves affected efficiency. Future research directions are suggested. (PsycINFO Database Record

본 연구는 귀인이론을 바탕으로 지상파 채널 브랜드의 진정성 지각에 관련된 선행변수 및 결과 변수를 제시하고, 그 관계를 검증하였다. 연구 결과 지상파 채널 브랜드의 차별성 지각은 SBS의 경우에만 진정성 지각에 유의한 영향을 미치는 것으로 나타났다. 반면, 지상파 채널 브랜드의 지속성 지각은 모든 채널에서 진정성 지각에 유의한 영향을 미쳤다. 다음으로, 차별성 지각이 브랜드 태도에 미치는 영향은 SBS의 경우에만 진정성 지각에 의해 부분매개 되는 것으로 나타났다. 그리고 지속성 지각이 브랜드 태도에 미치는 영향은 KBS와 SBS의 경우에는 진정성 지각에 의해 완전매개 되고, MBC의 경우에는 진정성 지각에 의해 부분매개 되었다. 지속성 지각이 브랜드 충성도에 미치는 영향은 MBC의 경우에만 진정성 지각에 의해 완전매개 되었다. 끝으로, 진정성 지각은 모든 채널에서 브랜드 태도에 유의한 영향을 미쳤다. 브랜드 충성도에 대한 진정성 지각의 직접적인 효과는 MBC의 경우에만 유의한 것으로 나타났으나, 간접효과는 모든 채널에서 유의했다. 연구결과를 바탕으로 이론적, 실무적 함의와 향후 연구방향을 제시하였다.

Objective: To investigate the potential of customized computer-based testing procedures to reduce the mean test length of the Posttraumatic Stress Checklist for DSM-5 (PCL-5). Method: A retrospective analysis was conducted using responses from 942 adults who had completed the full-length (20-item) PCL-5 in the aftermath of Hurricane Sandy. The abilities of 2 testing procedures, curtailment and stochastic curtailment, to lessen the instrument's mean test length while maintaining the same result as the full-length PCL-5 ("positive" or "negative") were evaluated in a post hoc simulation. Curtailment and stochastic curtailment track a respondent's answers as she takes the instrument and stop the test if future items are unable or unlikely to change the result. The performance of each procedure was recorded under 2 scoring methods: a total-score-based method and a cluster-based method. Each procedure's sensitivity, specificity, and overall agreement with the full-length PCL-5 were computed. Results: Curtailment reduced the mean test length by 40% under the total-score-based method, and by more than 70% under the cluster-based method, while exhibiting 100% sensitivity, specificity, and overall agreement with the full-length PCL-5. Stochastic curtailment reduced the mean test length by up to 88% under the total-score-based method, and up to 84% under the cluster-based method, while always exhibiting at least 92% sensitivity and 99.8% overall agreement, as well as 100% specificity, for the full-length PCL-5. Conclusions: Curtailment and stochastic curtailment have potential to enhance the efficiency of the PCL-5 when this assessment is administered by computer. The 2 procedures should be evaluated in future prospective studies. (PsycINFO Database Record

Mechanical behaviors of chopped, natural fiber composites with and without closed-cell microcellular foamed structures are investigated using finite element analysis (FEA), with references to previously conducted experimental measurements of the stress-strain characteristics of analogous test specimens and their microscopic images. Analytical and FEA models are compared for a simple, aligned fiber case; the FEA models are then extended to composites having more general fiber arrangements. These FEA results are compared to experimental stress-strain data. Scanning electron microscopy (SEM) images of fracture surfaces from test specimens are analyzed, and correlations between numerically predicted behaviors and fracture paths, and fracture surface images are discussed. The FEA results reflect experimental trends well including the effects of fibers and the presence of voids. These have also been found to induce specific regions of stress concentration. Inspection of fracture surfaces reveals transition from ductile to brittle behavior at low strain rates, generally brittle failure modes, and little evidence of fibers stressed to their tensile limits. Keywords: Finite element analysis, Scanning electron microscopy, Natural fiber composite, Microcellular foamed structure, Wheat straw

There is extensive knowledge on the relationship of posterior scleral biomechanics and intraocular pressure (IOP) load on glaucomatous optic neuropathy; however, the role for biomechanical influence of the perilimbal scleral tissue on the aqueous humor drainage pathway, including the distal venous outflow system, and IOP regulation is not fully understood. The purpose of this work is to study the outflow characteristics of perfused porcine eyes relative to the biomechanical properties of the perilimbal sclera, the posterior sclera and the cornea. Enucleated porcine eyes from eleven different animals were perfused with surrogate aqueous at two fixed flow rates while monitoring their IOP. After perfusion, mechanical stress-strain and relaxation tests were conducted on specimens of perilimbal sclera, posterior sclera, and cornea from the same perfused eyes. Statistical analysis of the data demonstrated a strong correlation between increased tangent modulus of the perilimbal sclera tissues and increased perfusion IOP (R2 = 0.74, p = 0.0006 at lower flow rate and R2 = 0.71, p = 0.0011 at higher flow rate). In contrast, there were no significant correlations between IOP and the tangent modulus of the other tissues (Posterior sclera: R2 = 0.17 at lower flow rate and R2 = 0.30 at higher flow rate; cornea: R2 = 0.02 at lower flow rate and R2

The effects of soy-based oil on the constitutive behavior of EPDM rubber have been investigated. Soy polyols with various hydroxyl numbers as well as unmodified soybean oil have each been incorporated in the EPDM rubber as a partial replacement for petroleum oil. Tensile tests have been performed at low and high rates, and hysteresis and stress relaxation tests have been performed at low rates. It has been found from the tensile tests that the rubber with soy polyol of low hydroxyl number can provide very similar constitutive characteristics as the control. On the other hand, the constitutive characteristics are significantly changed by using soy polyol of high hydroxyl number or unmodified soybean oil. For example, the rubber with unmodified soybean oil elongates substantially up to stretch ratios of 13, which is approximately 100% greater than that of the control. It has also been found from the tensile and hysteresis tests that the soy-based rubbers generally have better energy storing and dissipation characteristics than the control, such as storing more energy while maintaining lower peak stress, for an impact application. The test results indicate the potential for application based tuning of soy rubber properties by selecting an appropriate soy oil/EPDM blend or a polyol/EPDM blend with optimized functionality.

The mechanical properties of polypropylene (PP) composites with short, wheat straw natural-fiber reinforcements are studied in tension at various temperatures and rates of loading. Specimens of two fiber lengths have been considered with both closed-form, microcellular voids and in solid form. Results of mechanical stress-strain tests are given at static to moderate rates of strain, specifically 0.0005/s, 0.025/s and 14/s. Testing at these strain rates is conducted up to specimen failure at low, room and high temperatures of −30 °C, 22 °C, and 107 °C, respectively. Primary findings suggest that fibers increase the tangent modulus and ultimate stress, while reducing the failure strain, compared to pure polymer. The presence of microcellular voids generally reduces ultimate strength, but does not reduce failure strain. In many cases, the microcellular composites display reduced rate sensitivity that would result in the development of lower stress than solid counterparts during high rate and/or high strain events. The performance difference between the two fiber cases studied here is largest at room temperature and quasi-static strain rates, and in most cases becomes insignificant with increasing or decreasing temperature and increasing strain rates.

The damping characteristics of an Ni–Ti shape memory alloy (SMA) beam are theoretically and experimentally studied with interest in identifying an appropriate damping model for the material. The SMA beam is manufactured by a spray deposition method followed by heat treatment and found to have nanocrystalline structure in which damping capacity is high. The beam is then tested to obtain an impulse response and the frequency response function (FRF). By using the Hilbert transform technique it is shown that damping of the beam is almost amplitude independent in the tested range of displacement. It is also shown from the FRF that the damping of the spray-deposited shape memory alloy beam is well represented by a model including both linear viscous and hysteretic dampings.

Summary Long-term video-EEG monitoring (LTM) is the gold standard for initial lateralization and localization of seizures in the workup for neurosurgical treatment of medically intractable epilepsy. Previous studies have yielded contradictory results as to whether seizures that occur in clusters tend to arise from the same brain region and may lead to the incorrect conclusion that seizures arise from a single focus. To determine whether seizure clustering affects localization in an LTM setting, the authors performed an observational study over 6 years at a large regional epilepsy center on those undergoing LTM for seizure diagnosis, characterization, or presurgical workup. Excluding repeat studies and LTMs with generalized or nonepileptic seizures resulted in 479 monitorings with 2774 focal seizures for analysis. Sequential pairs of consecutive focal seizures were classed as "concordant", "discordant," or "other," based on EEG localization. ANOVA analysis on the logarithm of the interseizure interval (LISI) among the three seizure pair groups showed no significant difference, p =0.47, nor did analysis defining concordance as lateralization to the same hemisphere ( p =0.34). Analyses on subgroups with multifocal seizures, bilateral seizures, and extratemporal seizures all failed to show a significant difference. In conclusion, seizures have the same localizing value whether occurring in a cluster over a few hours or sporadically over a few days. This could potentially lead to shorter monitoring times.

Objective Visual hyperexcitability in the form of abnormal contrast gain control has been shown in photosensitive epilepsy and idiopathic generalized epilepsies. We assessed the accuracy and reliability of measures of visual contrast gain control in discerning individuals with idiopathic generalized epilepsies from healthy controls. Methods Twenty-four adult patients with idiopathic generalized epilepsy and 32 neurotypical control subjects from two study sites participated in a prospective, cross-sectional study. We recorded steady-state visual evoked potentials to a wide range of contrasts of a flickering grating stimulus. The resultant response magnitude vs. contrast curves were fitted to a standard model of contrast response function, and the model parameters were used as input features to a linear classifier to separate patients from controls. Additionally we compared the relative contribution of model parameters towards the classification using a sparse feature-selection approach. Results Classification accuracy was 80% or better. Sensitivity and specificity both were 80–85%. Cross validation confirmed robust classifier performance generalizable across the data from the two samples. Patients’ relative lack of gain control at high contrasts was the most important information distinguishing patients from controls. Conclusions Individuals with idiopathic generalized epilepsy were distinguishable from the neurotypical with a high degree of accuracy and reliability by a reduction in gain control at high contrasts. Significance Gain control is an essential neural operation that regulates neuronal sensitivity to stimuli and may represent a novel biomarker of hyperexcitability.

The high strain-rate constitutive behavior of polymer composites with various natural fibers is studied. Hemp, hemp/glass hybrid, cellulose, and wheat straw-reinforced polymeric composites have been manufactured, and a split-Hopkinson pressure bar apparatus has been designed to measure the dynamic stress–strain response of the materials. Using the apparatus, compressive stress–strain curves have been obtained that reveal the materials’ constitutive characteristics at strain rates between 600 and 2400 strain/s. Primary findings indicate that natural fibers in thermoset composites dissipate energy at lower levels of stress and higher strain than glass-reinforced composites. In the case of thermoplastic matrices, the effect on energy dissipation of natural fibers vs. conventional talc reinforcements is highly dependent on resin properties. Natural fibers in polypropylene homopolymer show improved reinforcement but have degraded energy dissipation compared to talc. Whereas in polypropylene copolymer, natural fibers result in improved energy dissipation compared to talc. These data are useful for proper design, analysis, and simulation of lightweight biocomposites.

The effects of loading rate on bio-, nano-, and microcellular composite systems have been studied. Fiber–resin systems have been manufactured and dynamically tested at various speeds to assess their strain-rate dependencies (rate hardening) and energy-dissipation characteristics compared to conventional materials. The following composite systems have been fabricated and studied: polypropylene/sisal fiber biocomposite, hemp/vinyl ester biocomposite, thermoplastic olefin/nanoclay composite, microcellular polypropylene/sisal fiber biocomposite, and microcellular thermoplastic olefin/nanoclay composite. It has been determined that the biocomposite systems studied possess unique energy dissipation characteristics and muted rate dependence, while the nanocomposite system did not. In addition, microcellular foaming of these materials further enhanced the effects. Though the exact mechanisms at play are not fully understood at this point, it has been found that in addition to the microcellular voids, the anatomical vasculature of the natural fibers may play a role in energy dissipation processes in these hybrid materials. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers

The thermo-mechanical analysis of an ultrasonic spot welding process was performed using developed finite element models. Temperature–time histories of aluminium specimens during welding were successfully obtained from the analysis and validated by physical tests. It was shown that the effect of frictional heating on the plastic deformation of aluminium during ultrasonic spot welding was significant and should be included in the analysis of the welding process in order to achieve good correlation with the physical phenomenon.

Stochastic curtailment is a sequential method to terminate a study when continuing to the end would be unlikely to change the outcome. This method has been researched most commonly in the context of clinical trials. The current paper explores its use in a different setting: the administration of a health questionnaire to patients via computer. A classification procedure augmenting logistic regression with stochastic curtailment is introduced to avoid burdening the patients with unnecessary questions. In a real-data simulation using responses from the Medicare Health Outcomes Survey, the new procedure substantially reduced the average number of questions administered with a minimal loss of classification accuracy.

Automated test assembly (ATA) has been an area of prolific psychometric research. Although ATA methodology is well developed for unidimensional models, its application alongside cognitive diagnosis models (CDMs) is a burgeoning topic. Two suggested procedures for combining ATA and CDMs are to maximize the cognitive diagnostic index and to use a genetic algorithm. Each of these procedures has a disadvantage: The cognitive diagnostic index cannot control attribute-level information and the genetic algorithm is computationally intensive. The goal of this article is to solve both problems by using binary programming, together with the item discrimination indexes of Henson et al., for performing ATA with CDMs. The three procedures are compared in simulation. Advantages and disadvantages of each are discussed.

Much recent psychometric literature has focused on cognitive diagnosis models (CDMs), a promising class of instruments used to measure the strengths and weaknesses of examinees. This article introduces a genetic algorithm to perform automated test assembly alongside CDMs. The algorithm is flexible in that it can be applied whether the goal is to minimize the average number of classification errors, minimize the maximum error rate across all attributes being measured, hit a target set of error rates, or optimize any other prescribed objective function. Under multiple simulation conditions, the algorithm compared favorably with a standard method of automated test assembly, successfully finding solutions that were appropriate for each stated goal.

It was theoretically shown by the authors in a previous article that by adding a layer of metal on the outside of a carbon fiber-reinforced composite shaft, the bending natural frequencies of the shaft could be increased in some cases due to reduction of the effects of shear deformation by the metal layer. In the present study, composite shafts having a metal casing have been manufactured by spray deposition process over filament wound, fiber reinforced polymeric shafts. The natural frequencies of the spray deposited composite shafts have been measured and found to compare well to theoretically calculated values. The experiments also confirm the shear deformation effect described above. Some manufacturing issues on the spray deposition of metals over carbon fiber-reinforced plastics are addressed.

The recent study of Oshima, Raju, and Nanda proposes the item parameter replication (IPR) method for assessing statistical significance of the noncompensatory differential item functioning (NCDIF) index within the differential functioning of items and tests (DFIT) framework. Previous Monte Carlo simulations have found that the appropriate cutoff values for determining statistical significance of NCDIF depend on sample size and the item response theory (IRT) model used for the analysis. The IPR method simplifies the process of identifying cutoff values that are tailored to a particular research setting. This approach has been shown to be effective for detecting differential item functioning (DIF) in dichotomous items. The current article extends the IPR method to the polytomous case.

Dynamic behaviours and stability of an automatic ball balancer (ABB) in an optical disk drive are analyzed based on the proposed three-dimensional dynamic model. For dynamic analysis, the feeding deck with the ball balancer and a spindle motor is modelled as a rigid body with six degrees of freedom. The nonlinear equations of motion are derived using Lagrange's equation in order to describe the translational and rotational motions of the system. From the derived nonlinear equations, the linearized equations of motion in the neighbourhood of a balanced equilibrium position are obtained by the perturbation method. These equations are coupled, linear, differential equations with time-dependent periodic coefficients, from which the stability of the system is analyzed by using the Floquet theory. Finally, the time responses are computed to verify the results of the stability analysis, and to investigate the balancing performance of the ABB.

The free in-plane vibration of an axially moving membrane is studied considering the effects of both the translating speed and aspect ratio of the membrane. Two sets of boundary conditions, which are free and fixed constraints in the lateral direction at boundaries with mass transport, are discussed in this study. From the extended Hamilton principle, the coupled equations of the longitudinal and lateral motions are derived. These equations are then discretized by using the Galerkin method. From the discretized equations, the natural frequencies and mode shapes are obtained for the variations of the translating speed and aspect ratio. The results show that the translating speed, aspect ratio, and boundary conditions have significant effects on the in-plane vibrations of the moving membrane.

3-Phenylamino-5-bromo-2-pyrone undergoes facile Diels–Alder cycloadditions with various electron deficient dienophiles to afford an array of functionally rich and stereochemically defined cycloadducts in good to excellent isolated yields. Due to the electron donacity of the amine group, it only proceeds in normal electron demand D–A cycloadditions. Subsequent ring openings with NaOMe provided constrained α-amino acid derivatives.

Recently, a new technique using cross-linking enzyme crystals (CLECs) was introduced in the field of enzyme technology. CLECs are solid crystalline particles which are insoluble in both water and organic solvents. Chemical cross-linking of the enzyme crystals preserves the catalytic activity even in harsh conditions such as at high temperature, at extreme pH, in organic solvents, and in the presence of proteases and radical chemicals. CLECs of cyclodextrin glucanotransferase (CGTase) could be useful biocatalysts because they were stable at elevated temperature, in organic solvents, and in the presence of enzyme inactivation surfactant. They also maintained their activity against protein-digesting enzyme.

Analytical studies of vortex-induced vibration (VTV) of cables during lock-in have considered small amplitude and relatively fast dynamic responses about an equilibrium configuration. However, this equilibrium may change as a result of the significantly increased mean drag created during lock-in. In response to increased drag, the cable may slowly drift downstream causing appreciable changes in cable geometry and tension. The resonance conditions for lock-in may be preserved during this slow drift or they may be disrupted. A nonlinear cable/fluid model is discussed mat captures both fast (small amplitude) motions due to VIV and slow (large amplitude) motions due to drift. These two different time scales of motion are clearly observed in numerical simulations. The significant interplay of the slow drifting motion and the fast VTV is highlighted.

International audience; Models of non-li near systems frequently introduce forces with bounded continuity resulting in non-smooth (even discontinuous) flow. Examples include systems with clearances, backlash, friction, and impulses. Asymptotic methods require smooth (differentiable) flow and are therefore ill-suited for analyzing non-smooth systems. In these cases, the traditional harmonic balance method may be used to obtain approximate periodic solutions, but the method suffers from extremely slow convergence in general. Generalizations of the traditional harmonic balance method are introduced in this paper that result in superior convergence rates and superior modes of convergence. These improvements derive from the introduction of one or more expansion functions that possesses the same degree of continuity as the exact solution. In particular, forming an infinite series of such functions results in an expansion in the same function space of the exact solution. This expansion converges pointwise to the exact solution and to all derivatives thereof. These improvements are illustrated by example upon re-evaluating a classical single degree-of-freedom model for friction-induced vibration.

Free non-linear vibration of a rotating thin ring with a constant speed is analyzed when the ring has both the in-plane and out-of-plane motions. The geometric non-linearity of displacements is considered by adopting the Lagrange strain theory for the circumferential strain instead of the infinitesimal strain theory. By using Hamilton's principle, the coupled non-linear partial differential equations are derived, which describe the out-of-plane bending and torsional motions as well as the in-plane bending and extensional motions. During deriving the equations of motion, we discuss how to model the circumferential stress and strain in order to consider the geometric non-linearity. Four models are established: three non-linear models and one linear model. For the four models, the linearized equations of motion are obtained in the neighbourhood of the steady state equilibrium position. Based on the linearized equations of the four cases, the natural frequencies are computed at various rotational speeds and then they are compared. Through the comparison, this study recommends which model is appropriate to describe the non-linear behaviour more precisely.