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Accurate acquisition of pulse energy is very important in the field of atomic energy technology. In the existing energy characterization methods, the multiple voltage thresholds (MVT) sampling method introduces prior information of pulse signals and combines it with trigger times from multiple reference voltages to achieve direct energy characterization, without any pulse shaping techniques. It involves no extra hardware components and has high count rate, rendering it applicable for a range of applications, including oil detection, medical imaging, etc. However, in conventional MVT sampling process, to record trigger times from one reference voltage threshold would consume one time-to-digital converters (TDC) unit. Since a TDC unit is not resource friendly, it would be notable challenging to apply this strategy in a multi-channel scenario, due to the increased power and cost. To address this, a resource-efficient multiple voltage thresholds (REMVT) sampling method was proposed. REMVT harnesses the fact that trigger times from each reference voltage appear sequentially and at a particular order, making it possible to record all of them using only a single TDC unit. To achieve this, the trigger signaling from each reference threshold voltage was routed together and fed to a combinatorial logic circuit. This logic circuit consumes few resources and can alter signal levels if an effective signaling arrive. By this means, the trigger times from each reference voltage were sequentially mapped to different edges. Deciphering interval between these edges would generate sufficient information for pulse reconstruction and hence energy characterization. This “TDC chain reuse” technique significantly reduces resource consumption. For example, in a configuration with 4/8 thresholds, resource consumption is reduced by 75%/87.5%. Additionally, this chain reuse technique reduces measurement variations from using multiple chains, leading to fewer jitters in time measurement and, consequently, better energy characterization performance. With REMVT, the energy characterization errors of 79% pulses are within 20.5%. While with MVT, this value reduces to 72%. Using this REMVT, an energy resolution of 13.2% for 511 keV can be obtained under practical experiment conditions, which is only 1.1% worse than the results obtained from a general high-speed oscilloscope. In addition, a new event detection and pileup event recovery algorithm was proposed in this paper. This algorithm fully exploits the prior information of pulses, namely the sequential order of each trigger time and the respective interval among them, to accomplish reliable event detection and accurate pileup event recovery. Results demonstrate that 93% pileup events can be identified and recovered.

In this report we provide preliminary evidence on the measurement characteristics for a new type of teaching performance assessment designed to be combined with complementary assessments of teacher content knowledge. The resulting test, which we refer to as the Foundational Assessment of Competencies for Teaching (FACT), is designed for use as part of initial teacher licensure. Twenty elementary FACT performance tasks (10 for mathematics [MATH] and 10 for reading language arts [RLA]) were developed and then administered to 59 teacher candidates. The results from the pilot indicate that the performance tasks function as designed with candidates completing the tasks on average in approximately 3.5 min. Human raters were able to score the tasks quickly and accurately. All score points were well represented for all the scored tasks. Total scores for all tasks combined and subscores for reading language arts RLA and MATH had respective alpha reliabilities of 0.86, 0.77, and 0.79, with the scores well distributed across the scale. A large majority of teacher candidates participating in the study strongly endorsed the FACT tasks as authentic, assessing valuable competencies, and suitable for use as part of teacher licensure. These preliminary results indicate that the FACT performance tasks show great promise for use in large-scale, high-stakes testing programs that seek to provide evidence of both the knowledge and skills needed for effective teaching.

In this study, we explored retest effects on test scores and response time for repeaters, examinees who retake an examination. We looked at two groups of repeaters: those who took the same form twice and those who took different forms on their two attempts for a certification and licensure test. Scores improved over the two test attempts, and repeaters taking the same form twice tended to have larger score gains than those taking different forms. This trend was more salient for female examinees than male and for White and Hispanic/Latino examinees than examinees from other ethnicity groups. In addition, over a third of the examinee responses were incorrect on the same form for both attempts, indicating that the knowledge required for these items was not addressed after these repeaters failed their initial attempt to answer those items correctly. Factors that may be related to these findings are discussed.

Demolding is the key step of micro-injection molding ([micro]IM), which influences the molding quality of polymer parts to a great extent. The essence of demolding is to overcome interface interactions between the mold cavity surface and the part surface, which is closely related to factors such as the cavity surface topography and process parameters. However, a theoretical model predicting the demolding force of [micro]IM is still lacking, resulting in the difficulty of improving the quality of demolding in [micro]IM. Therefore, a comprehensive demolding force model is proposed to clarify the demolding mechanism of [micro]IM. The model focuses on the adhesion behavior and friction behavior in the special contact mode formed by the replication effect of [micro]IM. The theory proof and computation results indicate that the cavity surface topography determines the contact mode of the mold-part interface (MPI), which in turn changes the real interface contact area, the composition mode of adhesion stress, and the friction forms, thereby affecting the adhesion and friction force during demolding. In addition, the process parameters can also change the contact mode of MPI as the process parameters have a great effect on the filling capacity and the degree of replication, thereby influencing the demolding process. KEYWORDS adhesion behavior, demolding force, friction behavior, interface contact mode, microinjection molding, theory and modeling, 1 | INTRODUCTION Micro polymer parts are widely used in medical science, aerospace, precision optics, microelectronics, and other fields. [1,2] As a mass production technique, microinjection molding ([micro]IM) is very [...]

With the increase in the aging population, senile osteoporosis (SOP) has become a major global public health concern. Here, it is found that Prx1 and Bmi‐1 co‐localized in trabecular bone, bone marrow cavity, endosteum, and periosteum. Prx1‐driven Bmi‐1 knockout in bone‐marrow mesenchymal stem cells (BMSCs) reduced bone mass and increased bone marrow adiposity by inhibiting osteoblastic bone formation, promoting osteoclastic bone resorption, downregulating the proliferation and osteogenic differentiation of BMSCs, and upregulating the adipogenic differentiation of BMSCs. However, Prx1‐driven Bmi‐1 overexpression showed a contrasting phenotype to Prx1‐driven Bmi‐1 knockout in BMSCs. Regarding mechanism, Bmi‐1‐RING1B bound to DNMT3A and promoted its ubiquitination and inhibited DNA methylation of Runx2 at the region from 45047012 to 45047313 bp, thus promoting the osteogenic differentiation of BMSCs. Moreover, Bmi‐1‐EZH2 repressed the transcription of Cebpa by promoting H3K27 trimethylation at the promoter region −1605 to −1596 bp, thus inhibiting the adipogenic differentiation of BMSCs. It is also found that Prx1‐driven Bmi‐1 overexpression rescued the SOP induced by Prx1‐driven Bmi‐1 knockout in BMSCs. Thus, Bmi‐1 functioned as a hub protein in the epigenetic regulation of BMSCs differentiation to delay bone aging. The Prx1‐driven Bmi‐1 overexpression in BMSCs can be used as an approach for the translational therapy of SOP. [ABSTRACT FROM AUTHOR]