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An important problem in the application of psychometric models is the selection of suitable algorithms for parameter estimation. In a recent publication, Urban and Bauer (Psychometrika 86:1-29, 2021) proposed an estimation algorithm based on deep learning for item parameter estimation for large sample sizes. In this article, we first investigate the accuracy of an adaptation of this estimation method for a multidimensional variation of the response time model proposed by Klein Entink, Fox and van der Linden (Psychometrika 74:21-48, 2009). As a second contribution, we propose and evaluate an extension of this estimation method for a joint factor model for responses and response times, which can be seen as a variation of the joint model for responses and response times of Klein Entink, Fox and van der Linden. Our results indicate that the deep learning algorithm can be used for an accurate item parameter estimation for these models even in relatively small datasets and is computationally fast in large datasets. The evaluated algorithm is freely available in a Python package. We also describe an empirical application of this method to the Amsterdam Chess Test dataset.

Coal dust explosions are a lethal threat to anyone working in an underground coal mine. Many coal mining countries including Australia and much of Europe already utilize passive barrier explosion suppressant systems but due to differences in ventilation patterns in the United States, simple passive systems such as the bagged barrier are not as cost effective. Active systems are triggered by properties of an explosion, such as pressure, heat, or light, and release or project a suppressant into the environment to suppress an explosion. To deploy an active system, the best sensor and suppressant release location and spacing must be determined; this must account for total system latency and explosive propagation speed. A 10:1 model of a longwall entry system has been developed to study the pressure wave propagation of coal dust explosions and consequent triggering of different suppressants. The scaled model, with its removable stoppings, allows multiple potential propagation pathways for an explosion to be repeatedly tested, different from typical straight shock tunnel tests. The layout also facilitates the placement of sensors and cameras to fully observe and document the tests. The pressure wave characteristics found at crosscuts and corners will aid in the development of active barrier trigger systems and spacing of suppressant release locations.

Faculty perceptions of student learning assessment were examined in the context of neoliberal trends in higher education in this exploratory survey study. For this preliminary study, a small department consisting of sixteen faculty members was surveyed. Responding faculty rated themselves as highly engaged in assessment, and rated course uses of assessment as more important than institutional uses of assessment. Faculty perceived administrators as placing more importance on institutional uses over course uses, though the gap between administrators and faculty was less in course uses than in institutional uses. Faculty ratings of neoliberal manifestations at their institution varied considerably, with a perceived institutional focus on job training over liberal arts education the most substantial item. Together, these findings set the stage for future research into whether neoliberal trends impact faculty engagement student learning assessment.

This paper examines the implications of scaling an n -type bulk-driven MOSFET into the 90 nm node in an effort to make the device suitable for analog designs operating at 0.7 V, the minimum supply voltage predicted for the end of bulk CMOS. Observations will suggest that process scaling has caused the g mb / g m ratio to degrade from 0.38 to 0.12 between representative 0.25 μm and 65 nm technologies and that the benefits expected from traditional bulk-driven circuit architectures are no longer present in deca-nanometer processes unless certain modifications are considered. Furthermore, it will be shown that the major disadvantages of the bulk-driven MOSFET – i.e., its low intrinsic gain, low cut-off frequency and layout area requirements – can be improved by as much as 110%, 50% and 53%, respectively, if delta doping (defined as a heavily-doped buried layer of 100 nm thickness) and deep trench isolation are used instead of conventional uniform doping and triple-well isolation.

Object Widespread use of MR imaging has contributed to the more frequent diagnosis of vestibular schwannomas (VSs). These tumors represent 10% of primary adult intracranial neoplasms, and if they are symptomatic, they usually present with hearing loss and tinnitus. Currently, there are 3 treatment options for quality of life (QOL): wait and scan, microsurgery, and radiosurgery. In this paper, the authors' purpose is to determine which treatment modality yields the highest QOL at 5- and 10-year follow-up, considering the likelihood of recurrence and various complications. Methods The MEDLINE, Embase, and Cochrane online databases were searched for English-language articles published between 1990 and June 2008, containing key words relating to VS. Data were pooled to calculate the prevalence of treatment complications, tumor recurrence, and QOL with various complications. For parameters in which incidence varied with time of follow-up, the authors used meta-regression to determine the mean prevalence rates at a specified length of follow-up. A decision-analytical model was constructed to compare 5- and 10-year outcomes for a patient with a unilateral tumor and partially intact hearing. The 3 treatment options, wait and scan, microsurgery, and radiosurgery, were compared. Results After screening more than 2500 abstracts, the authors ultimately included 113 articles in this analysis. Recurrence, complication rates, and onset of complication varied with the treatment chosen. The relative QOL at the 5-year follow-up was 0.898 of normal for wait and scan, 0.953 for microsurgery, and 0.97 for radiosurgery. These differences are significant (p < 0.0052). Data were too scarce at the 10-year follow-up to calculate significant differences between the microsurgery and radiosurgery strategies. Conclusions At 5 years, patients treated with radiosurgery have an overall better QOL than those treated with either microsurgery or those investigated further with serial imaging. The authors found that the complications associated with wait-and-scan and microsurgery treatment strategies negatively impacted patient lives more than the complications from radiosurgery. One limitation of this study is that the 10-year follow-up data were too limited to analyze, and more studies are needed to determine if the authors' results are still consistent at 10 years.

Object Outcomes in clinical trials on trigeminal pain therapies require instruments with demonstrated reliability and validity. The authors evaluated the Brief Pain Inventory (BPI) in its existing form plus an additional 7 facial-specific items in patients referred to a single neurosurgeon for a diagnosis of facial pain. The complete 18-item instrument is referred to as the BPI-Facial. Methods This study was a cross-sectional analysis of patients who completed the BPI-Facial. The diagnosis of classic versus atypical trigeminal neuralgia (TN) was made before analyzing the questionnaire results. A hypothesis-driven factor analysis was used to determine the principal components of the questionnaire. Item reliability and questionnaire validity were tested for these specific constructs. Results Data from 156 patients were analyzed, including 114 patients (73%) with classic and 42 (27%) with atypical TN. Using orthomax rotation factor analysis, 3 factors with an eigenvalue > 1.0 were identified—pain intensity, interference with general activities, and facial-specific pain interference—accounting for 97.6% of the observed item variance. Retention of the 3 factors was confirmed via a Cattell scree plot. Internal reliability was demonstrated by calculating Cronbach's α: 0.86 for pain intensity, 0.89 for interference with general activities, 0.95 for facial-specific pain interference, and 0.94 for the entire instrument. Initial validity of the BPI-Facial instrument was supported by the detection of statistically significant differences between patients with classic versus atypical pain. Patients with atypical TN rated their facial pain as more intense (atypical 6.24 vs classic 5.03, p = 0.013) and as having greater interference in general activities (atypical 6.94 vs classic 5.43, p = 0.0033). Both groups expressed high levels of facial-specific pain interference (atypical 6.34 vs classic 5.95, p = 0.527). Conclusions The BPI-Facial is a rigorous measure of facial pain in patients with TN and appears to have sound psychometric properties and is responsive to differences between classic and atypical TN. Future studies must assess the instrument's test-retest reliability, validity in additional populations, and responsiveness with respect to changes in patient outcomes following neurosurgical interventions and medical therapies.

Signal integrity has become a major problem in digital IC design. One cause is device scaling that results in a sharp reduction of supply voltage, creating stringent noise margin requirements to ensure functionality. This paper introduces both a novel on-chip decoupling capacitance methodology and active noise cancellation (ANC) structure. The decoupling methodology focuses on quantification and location. The ANC structure, with an area of 50 ?m × 55 ?m, uses decoupling capacitance to sense noise and inject a proportional current into VSS as a method of reduction. A chip has been designed and fabricated using TSMC's 90-nm technology. Measurements show that the decoupling methodology improved the average voltage headroom loss by 17% while the ANC structure improved the average voltage headroom loss by 18%.

A wetland mesocosm experiment was conducted to determine the effects on Mn retention of substrate type, surface water depth, and flow rate. The main objective of this experiment was to determine if sustained Mn retention could be accomplished under the specific experimental treatments, to recommend design parameters for the construction of field wetland systems for Mn treatment. Crushed limestone was clearly superior to spent mushroom substrate (SMS) with respect to Mn retention. The presence of a layer of free surface water detracted from Mn treatment, while lower flow rates enhanced Mn treatment. Sustained Mn retention was achieved using crushed limestone as the substrate coupled with an absence of surface free water, when inlet water had a pH of 7.0 and no appreciable Fe. Substrate metal extractions indicated that most of the Mn was retained as oxide-bound Mn (72%), with most (88%) of the Mn retained at the surface of the wetland. Limestone “wetlands” are therefore recommended in the treatment of Mn in neutral-pH mine water containing no Fe.

Widespread use of MR imaging has contributed to the more frequent diagnosis of vestibular schwannomas (VSs). These tumors represent 10% of primary adult intracranial neoplasms, and if they are symptomatic, they usually present with hearing loss and tinnitus. Currently, there are 3 treatment options for quality of life (QOL): wait and scan, microsurgery, and radiosurgery. In this paper, the authors' purpose is to determine which treatment modality yields the highest QOL at 5- and 10-year follow-up, considering the likelihood of recurrence and various complications.The MEDLINE, Embase, and Cochrane online databases were searched for English-language articles published between 1990 and June 2008, containing key words relating to VS. Data were pooled to calculate the prevalence of treatment complications, tumor recurrence, and QOL with various complications. For parameters in which incidence varied with time of follow-up, the authors used meta-regression to determine the mean prevalence rates at a specified length of follow-up. A decision-analytical model was constructed to compare 5- and 10-year outcomes for a patient with a unilateral tumor and partially intact hearing. The 3 treatment options, wait and scan, microsurgery, and radiosurgery, were compared.After screening more than 2500 abstracts, the authors ultimately included 113 articles in this analysis. Recurrence, complication rates, and onset of complication varied with the treatment chosen. The relative QOL at the 5-year follow-up was 0.898 of normal for wait and scan, 0.953 for microsurgery, and 0.97 for radiosurgery. These differences are significant (p0.0052). Data were too scarce at the 10-year follow-up to calculate significant differences between the microsurgery and radiosurgery strategies.At 5 years, patients treated with radiosurgery have an overall better QOL than those treated with either microsurgery or those investigated further with serial imaging. The authors found that the complications associated with wait-and-scan and microsurgery treatment strategies negatively impacted patient lives more than the complications from radiosurgery. One limitation of this study is that the 10-year follow-up data were too limited to analyze, and more studies are needed to determine if the authors' results are still consistent at 10 years.

Outcomes in clinical trials on trigeminal pain therapies require instruments with demonstrated reliability and validity. The authors evaluated the Brief Pain Inventory (BPI) in its existing form plus an additional 7 facial-specific items in patients referred to a single neurosurgeon for a diagnosis of facial pain. The complete 18-item instrument is referred to as the BPI-Facial.This study was a cross-sectional analysis of patients who completed the BPI-Facial. The diagnosis of classic versus atypical trigeminal neuralgia (TN) was made before analyzing the questionnaire results. A hypothesis-driven factor analysis was used to determine the principal components of the questionnaire. Item reliability and questionnaire validity were tested for these specific constructs.Data from 156 patients were analyzed, including 114 patients (73%) with classic and 42 (27%) with atypical TN. Using orthomax rotation factor analysis, 3 factors with an eigenvalue1.0 were identified-pain intensity, interference with general activities, and facial-specific pain interference-accounting for 97.6% of the observed item variance. Retention of the 3 factors was confirmed via a Cattell scree plot. Internal reliability was demonstrated by calculating Cronbach's alpha: 0.86 for pain intensity, 0.89 for interference with general activities, 0.95 for facial-specific pain interference, and 0.94 for the entire instrument. Initial validity of the BPI-Facial instrument was supported by the detection of statistically significant differences between patients with classic versus atypical pain. Patients with atypical TN rated their facial pain as more intense (atypical 6.24 vs classic 5.03, p = 0.013) and as having greater interference in general activities (atypical 6.94 vs classic 5.43, p = 0.0033). Both groups expressed high levels of facial-specific pain interference (atypical 6.34 vs classic 5.95, p = 0.527).The BPI-Facial is a rigorous measure of facial pain in patients with TN and appears to have sound psychometric properties and is responsive to differences between classic and atypical TN. Future studies must assess the instrument's test-retest reliability, validity in additional populations, and responsiveness with respect to changes in patient outcomes following neurosurgical interventions and medical therapies.

With the advent of system-on-a-chip integration, analog components are being forced to co-exist with their digital counterparts in scaled processes where the supply voltage, V DD , is expected to fall to 0.7 V by 2012 [1]. As a result of this integration, traditional analog topologies suffer from voltage headroom constraints since the threshold voltage, V T , can no longer scale proportionately with V DD due to sub-threshold leakage constraints. In 1996, Blalock described how the bulk terminal of a MOSFET could be used as a device input to enable analog design at very low supply voltages [2]. Using the MOSFET in this way, one could eliminate V T from the signal path allowing for a significant rise in the available voltage headroom. However, this device, called the bulk-driven (BD) MOSFET, suffered from intrinsic gain limitations because it depended upon the transconductance of the bulk, g mb , rather than the gate (g m ). Since Blalock's initial investigation, there has been no effort undertaken to make the BD MOSFET more adaptable to modern processes even though there have been numerous publications of low voltage analog designs incorporating the use of BD MOSFETs in these technologies. Therefore, this paper takes the first step towards creating a BD MOSFET that has been optimized for modern processes by proposing the use of delta doping [3] to improve g mb ; this claim will be verified through 2-D device simulations in ATLAS [4] and the results will be compared against halo-implanted devices which are currently being used in circuits utilizing the BD MOSFET. Furthermore, this paper will investigate the role that quantum mechanical (QM) confinement and gate oxide thickness, t ox , play in the performance of BD MOSFETs. Simulation results show that QM effects do not degrade g mb as aggressively as g m and that the t ox requirements necessary for gate-driven (GD) devices can be relaxed when using the bulk as an input.

This paper investigates the impact of device scaling on the bulk-driven MOSFET. In particular, the behavior of g mb is observed across process technology and it is shown that the g mb /g m ratio falls from 0.38 to 0.12 between IBM's 0.25 μm and 65 nm bulk CMOS processes via simulation. Delta and step doping are then proposed to enable the scaling of bulk-driven MOSFETs down to a channel length of 80 nm on a one volt supply. Using 2-D device simulations in ATLAS, it is shown that the intrinsic gain of a bulk-driven MOSFET can be enhanced by as much as 78% for a step doping profile and 106% for a delta doping profile in an NMOS device when compared to a uniform substrate.

First-generation total ankle arthroplaty designs had unacceptably high complication and failure rates compared with ankle arthrodesis. More recent prostheses have had encouraging intermediate results because of refined surgical techniques and improved designs. Mobile-bearing designs theoretically offer less wear and loosening through full conformity and minimal constraint. The less complex fixed-bearing designs avoid bearing dislocation and the potential for added wear from a second articulation. Four second-generation designs have demonstrated reasonable functional outcomes: the Scandinavian Total Ankle Replacement, the Agility Ankle, the Buechel-Pappas Total Ankle Replacement, and the TNK ankle. Intermediate results are promising but should be interpreted with care.

This paper examines value influences of four care modalities of the long-term care industry: independent or congregate, assisted living, nursing, and subacute care. Six influences that affect asset values are identified and examined. They comprise the evolution of managed care, financing, buyer motivations, seller motivations, opportunities, and threats. Their effect is examined through per-unit sale prices and capitalization rates over the past six years. While their effect on value differs, they are unified by several underlying themes that indicate that the market will ultimately reward and align with the lowest cost quality providers.

This paper presents the design of an n-type bulk-driven MOSFET which is intended to facilitate the scaling of analogue circuitry down to 0.7 V, the minimum supply voltage predicted for the end of bulk CMOS. The bulk-driven MOSFET design will be carried out in two parts using the design rules of a standard 90 nm bulk CMOS technology. First, the impact of gate oxide scaling will be investigated to see how the bulk transconductance behaves as the oxide thickness is varied. Results will indicate that the oxide scaling requirements of a MOSFET can be relaxed by 0.4 nm when the bulk is used as the input terminal rather than the gate. Second, by taking advantage of a larger oxide thickness, it will be shown that a delta-doped profile is capable of improving the intrinsic gain and cut-off frequency of a bulk-driven MOSFET by as much as 429% and 71%, respectively, when compared to a uniformly doped bulk-driven device consistent with the specifications of a 90 nm bulk CMOS process. Overall, the delta-doped bulk-driven MOSFET will exhibit a long-channel bulk-to-gate transconductance ratio equal to 0.51, compared to 0.27 in the uniformly doped device (the gate transconductance was the same in both devices). The new delta-doped design will also increase the bulk-driven-to-gate-driven cut-off frequency ratio to 0.095–0.492 for channel lengths ranging from 80–800 nm, which is a 16–34% improvement over the uniformly doped case. When used in a differential amplifier circuit, the delta-doped bulk-driven MOSFET was found to have a dc voltage gain 185% higher than that of a similar amplifier utilizing uniformly doped devices.