Diagnostic classification models (DCMs) have seen wide applications in educational and psychological measurement, especially in formative assessment. DCMs in the presence of testlets have been studied in recent literature. A key ingredient in the statistical modeling and analysis of testlet-based DCMs is the superposition of two latent structures, the attribute profile and the testlet effect. This paper extends the standard testlet DINA (T-DINA) model to accommodate the potential correlation between the two latent structures. Model identifiability is studied and a set of sufficient conditions are proposed. As a byproduct, the identifiability of the standard T-DINA is also established. The proposed model is applied to a dataset from the 2015 Programme for International Student Assessment. Comparisons are made with DINA and T-DINA, showing that there is substantial improvement in terms of the goodness of fit. Simulations are conducted to assess the performance of the new method under various settings.

Time limits are imposed on many computer-based assessments, and it is common to observe examinees who run out of time, resulting in missingness due to not-reached items. The present study proposes an approach to account for the missing mechanisms of not-reached items via response time censoring. The censoring mechanism is directly incorporated into the observed likelihood of item responses and response times. A marginal maximum likelihood estimator is proposed, and its asymptotic properties are established. The proposed method was evaluated and compared to several alternative approaches that ignore the censoring through simulation studies. An empirical study based on the PISA 2018 Science Test was further conducted.

The recent surge of interests in cognitive assessment has led to the development of cognitive diagnosis models. Central to many such models is a specification of the Q-matrix, which relates items to latent attributes that have natural interpretations. In practice, the Q-matrix is usually constructed subjectively by the test designers. This could lead to misspecification, which could result in lack of fit of the underlying statistical model. To test possible misspecification of the Q-matrix, traditional goodness of fit tests, such as the Chi-square test and the likelihood ratio test, may not be applied straightforwardly due to the large number of possible response patterns. To address this problem, this paper proposes a new statistical method to test the goodness fit of the Q-matrix, by constructing test statistics that measure the consistency between a provisional Q-matrix and the observed data for a general family of cognitive diagnosis models. Limiting distributions of the test statistics are derived under the null hypothesis that can be used for obtaining the test p-values. Simulation studies as well as a real data example are presented to demonstrate the usefulness of the proposed method.

Our study aimed to develop and validate a nomogram to assess talaromycosis risk in hospitalized HIV-positive patients. Prediction models were built using data from a multicentre retrospective cohort study in China. On the basis of the inclusion and exclusion criteria, we collected data from 1564 hospitalized HIV-positive patients in four hospitals from 2010 to 2019. Inpatients were randomly assigned to the training or validation group at a 7:3 ratio. To identify the potential risk factors for talaromycosis in HIV-infected patients, univariate and multivariate logistic regression analyses were conducted. Through multivariate logistic regression, we determined ten variables that were independent risk factors for talaromycosis in HIV-infected individuals. A nomogram was developed following the findings of the multivariate logistic regression analysis. For user convenience, a web-based nomogram calculator was also created. The nomogram demonstrated excellent discrimination in both the training and validation groups [area under the ROC curve (AUC) = 0.883 vs. 0.889] and good calibration. The results of the clinical impact curve (CIC) analysis and decision curve analysis (DCA) confirmed the clinical utility of the model. Clinicians will benefit from this simple, practical, and quantitative strategy to predict talaromycosis risk in HIV-infected patients and can implement appropriate interventions accordingly.

The maser instability associated with the loss-cone distribution has been widely invoked to explain the radio bursts observed in the astrophysical plasma environment, such as aurora and corona. In the laboratory plasma of a tokamak, events reminiscent of these radio bursts have also been frequently observed as an electron cyclotron emission (ECE) burst in the microwave range ($\mathrm{\sim }2{f_{\textrm{ce}}}$ near the last closed flux surface) during transient magnetohydrodynamic events. These bursts have a short duration of ~10 μs and display a radiation spectrum corresponding to a radiation temperature ${T_{e,\textrm{rad}}}$ of over $30\ \textrm{keV}$ while the edge thermal electron temperature ${T_e}$ is only in the range of $1\ \textrm{keV}$. Suprathermal electrons can be generated through magnetic reconnection, and a loss-cone distribution can be generated through open stochastic field lines in the magnetic mirror of the near-edge region of a tokamak plasma. Radiation modelling shows that a sharp distribution gradient $\partial f/\partial {v_ \bot } > 0$ at the loss-cone boundary can cause a negative absorption of ECE radiation through the maser instability. The negative absorption then amplifies the radiation so that the microwave intensity is significantly stronger than the thermal value. The significant ${T_{e,\textrm{rad}}}$ from the simulations suggests the potential role of the loss-cone maser instability in generating the ECE burst in a tokamak.

Timing of food intake is an emerging aspect of nutrition; however, there is a lack of research accurately assessing food timing in the context of the circadian system. The study aimed to investigate the relation between food timing relative to clock time and endogenous circadian timing with adiposity and further explore sex differences in these associations among 151 young adults aged 18–25 years. Participants wore wrist actigraphy and documented sleep and food schedules in real time for 7 consecutive days. Circadian timing was determined by dim-light melatonin onset (DLMO). The duration between last eating occasion and DLMO (last EO-DLMO) was used to calculate the circadian timing of food intake. Adiposity was assessed using bioelectrical impedance analysis. Of the 151 participants, 133 were included in the statistical analysis finally. The results demonstrated that associations of adiposity with food timing relative to circadian timing rather than clock time among young adults living in real-world settings. Sex-stratified analyses revealed that associations between last EO-DLMO and adiposity were significant in females but not males. For females, each hour increase in last EO-DLMO was associated with higher BMI by 0·51 kg/m2 (P = 0·01), higher percent body fat by 1·05 % (P = 0·007), higher fat mass by 0·99 kg (P = 0·01) and higher visceral fat area by 4·75 cm2 (P = 0·02), whereas non-significant associations were present among males. The findings highlight the importance of considering the timing of food intake relative to endogenous circadian timing instead of only as clock time.

This study investigates the molecular intricacies of the transmembrane protein TSP11 gene in Echinococcus strains isolated from livestock and patients in Yunnan Province afflicted with Echinococcus granulosus (E. granulosus) between 2016 and 2020. Gene typing analysis of the ND1 gene revealed the presence of the G1 type, G5 type and untyped strains, constituting 52.4, 38.1 and 9.5%, respectively. The analysis of 42 DNA sequences has revealed 24 novel single nucleotide polymorphic sites, delineating 11 haplotypes, all of which were of the mutant type. Importantly, there were no variations observed in mutation sites or haplotypes in any of the hosts. The total length of the TSP11 gene's 4 exons is 762 bp, encoding 254 amino acids. Our analysis posits the existence of 6 potential B-cell antigenic epitopes within TSP11, specifically at positions 49-KSN-51, 139-GKRG-142, 162-DNG-164, 169-NGS-171, 185-DS-186 and 231-PPRFTN-236. Notably, these epitopes exhibit consistent presence among various intermediate hosts and haplotypes. However, further validation is imperative to ascertain their viability as diagnostic antigens for E. granulosus in the Yunnan Province.

This research communication screened and identified differentiated expressed genes in bovine mammary epithelial cells (BMECs) upon prolactin (PRL) stimulation. PRL of 5 μg/ml increased β-casein synthesis in BMECs with milk protein synthesis capacity. RNA sequencing (RNA-seq) was used to screen differentially expressed genes (DEGs). A total of 375 DEGs (165 up-regulated and 210 down-regulated) were identified between PRL-stimulated group and the control group. Gene ontology enrichment analysis showed that the up-regulated genes were primarily associated with cell functions, metabolic processes, and biological regulatory processes. Pathway enrichment analysis showed that the up-regulated genes were mainly enriched in JAK-STAT, Rap1, Ras and Notch signaling pathways, which are widely involved in cell proliferation, differentiation and milk component synthesis. This study provides an initial understanding of the changes in gene expression in BMECs with PRL-stimulation, as determined by RNA-seq transcriptomic analysis, thereby enhancing our knowledge of the molecular regulation of lactation metabolism.

To meet the demands of laser-ion acceleration at a high repetition rate, we have developed a comprehensive diagnostic system for real-time and in situ monitoring of liquid sheet targets (LSTs). The spatially resolved rapid characterizations of an LST’s thickness, flatness, tilt angle and position are fulfilled by different subsystems with high accuracy. With the help of the diagnostic system, we reveal the dependence of thickness distribution on collision parameters and report the 238-nm liquid sheet generated by the collision of two liquid jets. Control methods for the flatness and tilt angle of LSTs have also been provided, which are essential for applications of laser-driven ion acceleration and others.

Here, we report the generation of MeV alpha-particles from H-11B fusion initiated by laser-accelerated boron ions. Boron ions with maximum energy of 6 MeV and fluence of 109/MeV/sr@5 MeV were generated from 60 nm-thick self-supporting boron nanofoils irradiated by 1 J femtosecond pulses at an intensity of 1019 W/cm2. By bombarding secondary hydrogenous targets with the boron ions, 3 × 105/sr alpha-particles from H-11B fusion were registered, which is consistent with the theoretical yield calculated from the measured boron energy spectra. Our results demonstrated an alternative way toward ultrashort MeV alpha-particle sources employing compact femtosecond lasers. The ion acceleration and product measurement scheme are referential for the studies on the ion stopping power and cross section of the H-11B reaction in solid or plasma.

Aphids exhibit seasonally alternating asexual and sexual reproductive modes. Different morphs are produced throughout the life cycle. To evaluate morph-specific fitness during reproductive switching, holocyclic Sitobion avenae were induced continuously under short light conditions, and development and reproduction were compared in each morph. Seven morphs, including apterous and alate virginoparae, apterous and alate sexuparae, oviparae, males, and fundatrices, were produced during the life cycle. The greatest proportions of sexuparae, oviparae, males, and virginoparae were in the G1, G2, G3, and G4 generations, respectively. Regardless of asexual or sexual morphs, alate morphs exhibited a marked delay in age at maturity compared with that of apterous morphs. Among the alate morphs, males had the longest age at maturity, followed by sexuparae and virginoparae. Among the apterous morphs, sexuparae were older at maturity than the fundatrices, virginoparae, and oviparae. The nymphs of each morph had equal survival potentials. For the same wing morphs, apterous sexuparae and oviparae exhibited substantial delays in the pre-reproductive period and considerable reductions in fecundity, compared with those of apterous virginoparae and fundatrices, whereas alate sexuparae and alate virginoparae had similar fecundity. The seven morphs exhibited Deevey I survivorship throughout the life cycle. These results suggest that sexual production, particularly in males, has short-term development and reproduction costs. The coexistence of sexual and asexual morphs in sexuparae offspring may be regarded as an adaptive strategy for limiting the risk of low fitness in winter.

Mammalian oocytes not fertilized immediately after ovulation can undergo ageing and a rapid decline in quality. The addition of antioxidants can be an efficient approach to delaying the oocyte ageing process. Onion peel extract (OPE) contains quercetin and other flavonoids with natural antioxidant activities. In this study, we investigated the effect of OPE on mouse oocyte ageing and its mechanism of action. The oocytes were aged in vitro in M16 medium for 16 h after adding OPE at different concentrations (0, 50, 100, 200, and 500 μg/ml). The addition of 100 μg/ml OPE reduced the oocyte fragmentation rate, decreased the reactive oxygen species (ROS) level, increased the glutathione (GSH) level, and improved the mitochondrial membrane potential compared with the control group. The addition of OPE also increased the expression of SOD1, CAT, and GPX3 genes, and the caspase-3 activity in OPE-treated aged oocytes was significantly lower than that in untreated aged oocytes and similar to that in fresh oocytes. These results indicated that OPE delayed mouse oocyte ageing by reducing oxidative stress and apoptosis and enhancing mitochondrial function.

Post-acceleration of protons in helical coil targets driven by intense, ultrashort laser pulses can enhance ion energy by utilizing the transient current from the targets’ self-discharge. The acceleration length of protons can exceed a few millimeters, and the acceleration gradient is of the order of GeV/m. How to ensure the synchronization between the accelerating electric field and the protons is a crucial problem for efficient post-acceleration. In this paper, we study how the electric field mismatch induced by current dispersion affects the synchronous acceleration of protons. We propose a scheme using a two-stage helical coil to control the current dispersion. With optimized parameters, the energy gain of protons is increased by four times. Proton energy is expected to reach 45 MeV using a hundreds-of-terawatts laser, or more than 100 MeV using a petawatt laser, by controlling the current dispersion.

Suppose you need to complete a task of 5 steps, each of which has equal difficulty and pass rate. You somehow have a privilege that can ensure you pass one of the steps, but you need to decide which step to be privileged before you start the task. Which step do you want to privilege? Mathematically speaking, the effect of each step on the final outcome is identical, and so there seems to be no prima facie reason for a preference. Five studies were conducted to explore this issue. In Study 1, participants could place the privilege on any of steps 1–5. Participants were most inclined to privilege step 5. In Study 2, participants needed to pay some money to purchase the privilege for steps 1–5, respectively. Participants would pay most money for step 5. Study 3 directly reminded participants that the probability of success of the whole task is mathematically the same, no matter on which step the privilege is placed, but most of the participants still prefer to privilege the final step. Study 4 supposed that the outcomes of all steps were not announced until all steps were finished, and asked how painful participants would feel if they passed all steps but one. People thought they would feel most painful when they failed at the final step. In Study 5, an implicit association test showed that people associated the first step with easy and the final step with hard. These results demonstrated the phenomenon of the final step effect and suggested that both anticipated painfulness and stereotype may play a role in this phenomenon.

In vitro rearing of honey bee larvae is ideal for bioassay studies; no honey bee stable cell lines are available. Inconsistency of internal development staging of reared larvae and a susceptibility to contamination are common problems encountered. Standardized protocols on rearing larvae in vitro to make the larvae growth and development more similar to that of natural colonies are necessary to ensure the accuracy of experimental results and promote honey bee research as a model organism. Here, we concluded that when larval fasting weight was >160 mg, the time point of gut emptying can be defined as the critical point separating the larval and prepupal stages. In this way, we can conduct precise studies on the prepupal stage, such as organ remodeling during metamorphosis. Simultaneously, we further verified that recombinant AccApidaecin in genetic engineered bacteria added to the larval diet upregulated antibacterial peptide gene expression, and did not stimulate the stress response in larvae, nor did it affect the pupation rate or eclosion rate. This demonstrated that feeding recombinant AccApidaecin can enhance the individual antibacterial ability at the molecular level.