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This study introduces a practical work activity that allows students to investigate the inhibitory effects of seed extracts on pancreatic lipase activity. The activity is related to the issue of the ongoing global obesity epidemic and involves the use of materials and chemicals readily available in high school laboratories. We show how the activity can help students understand how scientists can control the reaction rates of key enzymes involved in the digestion of dietary fat, to combat obesity. The activity also illustrates how instructional scaffolding can help students understand important procedures related to the design, measurement, and handling of data which are critical in ensuring success among students performing scientific investigations.

Persistence of the human immunodeficiency virus type-1 (HIV-1) latent reservoir in infected individuals remains a problem despite fully suppressive antiretroviral therapy (ART). While reservoir formation begins during acute infection, the mechanisms responsible for its establishment remain unclear. CD8+ T cells are important during the initial control of viral replication. Here we examined the effect of CD8+ T cells on formation of the latent reservoir in simian immunodeficiency virus (SIV)-infected macaques by performing experimental CD8+ depletion either before infection or before early (that is, day 14 post-infection) ART initiation. We found that CD8+ depletion resulted in slower decline of viremia, indicating that CD8+ lymphocytes reduce the average lifespan of productively infected cells during acute infection and early ART, presumably through SIV-specific cytotoxic T lymphocyte (CTL) activity. However, CD8+ depletion did not change the frequency of infected CD4+ T cells in the blood or lymph node as measured by the total cell-associated viral DNA or intact provirus DNA assay. In addition, the size of the persistent reservoir remained the same when measuring the kinetics of virus rebound after ART interruption. These data indicate that during early SIV infection, the viral reservoir that persists under ART is established largely independent of CTL control.

Objective The aim of this study was to develop a deep learning algorithm for detection of active inflammatory sacroiliitis in short tau inversion recovery (STIR) sequence MRI. Methods A total of 326 participants with axial SpA, and 63 participants with non-specific back pain (NSBP) were recruited. STIR MRI of the SI joints was performed and clinical data were collected. Region of interests (ROIs) were drawn outlining bone marrow oedema, a reliable marker of active inflammation, which formed the ground truth masks from which ‘fake-colour’ images were derived. Both the original and fake-colour images were randomly allocated into either the training and validation dataset or the testing dataset. Attention U-net was used for the development of deep learning algorithms. As a comparison, an independent radiologist and rheumatologist, blinded to the ground truth masks, were tasked with identifying bone marrow oedema in the MRI scans. Results Inflammatory sacroiliitis was identified in 1398 MR images from 228 participants. No inflammation was found in 3944 MRI scans from 161 participants. The mean sensitivity of the algorithms derived from the original dataset and fake-colour image dataset were 0.86 (0.02) and 0.90 (0.01), respectively. The mean specificity of the algorithms derived from the original and the fake-colour image datasets were 0.92 (0.02) and 0.93 (0.01), respectively. The mean testing dice coefficients were 0.48 (0.27) for the original dataset and 0.51 (0.25) for the fake-colour image dataset. The area under the curve of the receiver operating characteristic (AUC-ROC) curve of the algorithms using the original dataset and the fake-colour image dataset were 0.92 and 0.96, respectively. The sensitivity and specificity of the algorithms were comparable with the interpretation by a radiologist, but outperformed that of the rheumatologist. Conclusion An MRI deep learning algorithm was developed for detection of inflammatory sacroiliitis in axial SpA.

The Hong Kong Society of Rheumatology (HKSR) has developed evidence-based position statements on the use of magnetic resonance imaging (MRI) in axial spondyloarthritis (axSpA). A special interest group (SIG) developed the statements based on the literature review of the following research questions: 1) In whom should SI joint MRI be done to diagnose axSpA? 2) Should spine MRI be performed for diagnosis of axSpA? 3) Should spine and SI joint MRI be used in the assessment and monitoring of disease activity? 4) Which MRI sequence(s) should be used in axSpA? These statements have at least 75% agreement from voting rheumatology fellows of HKSR, and are developed to serve as local practice guidelines for rheumatologists and musculoskeletal radiologists in the management of axSpA.

Effects of the hot and dense plasma on the doubly excited states (DES) of the four-electron beryllium-like ions (BLI) with Z varying from 4 to 10 have been investigated by applying the stabilization method. The Debye–Huckel model has been used to describe the effective potential in the plasma. The four-electron ions are treated as an effective three-body problem by means of the method of model potential. One, four and five DESs lying above the 1s 2 2p threshold are found to exist in the ions having Z = 4 , Z = 5 and Z = 6 − 10 respectively. For the plasma-free case our results for the energy and width of the DESs are in agreement with the available results in the literature. A detailed study is made on the changes of energy and width of the DESs of the ions with varying plasma screening strength. Particular emphasis is given to explore the effects of the plasma on the whole sequence of ions.

Objectives This study sought to identify electrocardiographic (ECG) and clinical predictors of sudden cardiac arrest (SCA) in sarcoidosis. Background Sudden cardiac death (SCD) is the leading cause of death in cardiac sarcoidosis (CS) and may be the earliest manifestation of disease. Widespread or repeated advanced imaging is a challenging solution to this problem. ECG is an affordable and widely accessible modality that could help guide diagnostic approaches and risk stratification. Methods Data were obtained from the National Inpatient Sample (2005–2017) using International Classification of Diseases-9th Revision and -10th Revision-Clinical Modification. The primary outcome was to identify predictors of SCA, whereas predictors of SCA in young individuals and those with normal ventricular function served as secondary measures. Furthermore, temporal trends in sarcoidosis as well as SCA were also analyzed. Logistic regression analysis was used to calculate odds ratios, following which a multivariable regression was used to adjust for potential confounders. Results Electrocardiographic markers of AV node dysfunction or bundle branch block are associated with substantially increased risk of SCA in a limited proportion of patients (8.6%). This association is also observed among younger patients ( Conclusions ECG evidence of AV nodal dysfunction or distal conduction disease should raise suspicion for cardiac involvement in patients with sarcoidosis and are associated with increased risk of SCA. ECG markers could help identify patients who would benefit from advanced imaging. The sensitivity of ECGs is, however, limited and presence of a normal ECG does not reflect a low risk of SCA.

Introduction/aims Anti- 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGCR) myopathy is a rare but serious complication of statin use. The aim of this study was to describe the imaging features of statin-associated anti-HMGCR myopathy on thigh muscle magnetic resonance imaging (MRI). Methods Thigh muscle MRI images of 6 patients with statin associated anti-HMGCR myopathy were reviewed for muscle edema, fatty replacement and fascial edema in 4 compartments of each thigh: gluteal, anterior, medial and posterior. Signal intensity ratio (SIR) was calculated in 17 muscles in both thighs on T2-weighted fat-suppressed images. Intracompartmental comparison of T2 SIRs of different muscles were performed. Results All patients demonstrated bilateral symmetrical pan-compartmental muscle edema. Three patients had fatty infiltration, involving gluteal and/or posterior compartments. In the anterior compartment, rectus femoris and vastus lateralis most frequently demonstrated the highest T2 SIR. In the posterior compartment, semimembranosus most frequently demonstrated the highest T2 SIR. The long head of the biceps femoris always had a higher T2 SIR than the short head. Discussion Statin-associated anti-HMGCR myopathy commonly demonstrates bilateral symmetrical pan-compartmental edema on thigh muscle MRI, with anterolateral predilection in the anterior compartment, and greater involvement of the semimembranosus with relative sparing of the short head of the biceps femoris in the posterior compartment. These observations can contribute to the diagnosis of statin-associated anti-HMGCR myopathy.

Cystic fibrosis (CF) is caused by mutations in a chloride channel called the human Cystic Fibrosis Transmembrane Conductance Regulator (hCFTR). We used cryo-EM global conformational ensemble reconstruction to characterize the mechanism by which the breakthrough drug VX445 (Elexacaftor) simultaneously corrects both protein-folding and channel-gating defects caused by CF mutations. VX445 drives hCFTR molecules harboring the gating-defective G551D mutation towards the open-channel conformation by binding to a site in the first transmembrane domain. This binding interaction reverses the usual pathway of allosteric structural communication by which ATP binding activates channel conductance, which is blocked by the G551D mutation. Our ensemble reconstructions include a 3.4 Å non-native structure demonstrating that detachment of the first nucleotide-binding domain of hCFTR is directly coupled to local unfolding of the VX445 binding site. Reversal of this unfolding transition likely contributes to its corrector activity by cooperatively stabilizing NBD1 and the transmembrane domains of hCFTR during biogenesis.SummaryCryo-EM global conformational ensemble reconstruction has been used to characterize the mechanism-of-action of a breakthrough pharmaceutical that corrects fatal protein-folding and channel-gating defects in the human cystic fibrosis transmembrane conductance regulator (CFTR).

A retrospective cohort study.This study aims to determine whether quantitative magnetic resonance imaging (MRI) parameters and radiological scoring systems could be used as a reliable assessment tool for predicting neurological recovery trajectory following acute traumatic central cord injury syndrome (CCS).Controversy remains in whether CCS should be managed conservatively or by early surgical decompression. It is essential to understand how clinical and radiological parameters correlate with neurological deficits and how they predict recovery trajectories.We identified patients with CCS admitted between 2011 and 2018 with a minimum of 1-year follow-up. Cervical MRIs were analyzed for cord/canal dimensions, Brain and Spinal Injury Center (BASIC) scores and sagittal grading as ordinal scales of intraparenchymal cord injury. Japanese Orthopaedic Association (JOA) recovery rates (≥50% as good, 50% as poor) were analyzed against these variables by logistic regression and receiver operator characteristic (ROC) curves. Additionally, we evaluated American Spinal Injury Association motor scale (AMS) scores/recovery rates.Sixty patients were included, of which 30 were managed conservatively and 30 via surgical decompression. The average follow-up duration for the entire cohort was (51.1 ± 25.7) months. Upon admission, sagittal grading correlated with AMS and JOA scores (P 0.01, β = 0.48). Volume of the C2 to C7 canal and axial cord area over the site of maximal compression correlated with AMS and JOA scores respectively (P = 0.04, β = 0.26; P = 0.01, β = 0.28). We determined admission AMS more than 61 to be a clinical cutoff for good recovery (area under the receiver operating curve [AUC] = 0.74, 95% confidence interval [CI]: 0.61-0.85, sensitivity 80.9%, specificity 69.2%, P 0.01). Radiological cutoffs to identify patients with poor recovery rates were length of cervical spinal stenosis more than 3.9 cm (AUC = 0.76, 95% CI: 0.63-0.87, specificity 91.7%, sensitivity 52.2%, P 0.01), BASIC score of more than 1 (AUC = 0.69, 95% CI: 0.56-0.81, specificity 80.5%, sensitivity 51.1%, P = 0.02). Surgical decompression performed as a salvage procedure upon plateau of recovery did not improve neurological outcomes.Clinical and radiological parameters upon presentation were prognosticative of neurological recovery rates in CCS. Surgery performed beyond the acute post-injury period failed to improve outcomes.Level of Evidence: 3.

MXenes as a new family of two-dimensional (2D) materials have attracted increasing attention recently because of their outstanding physical and chemical properties and versatile applications, especially in energy storage and catalysis. This review will focus on the catalytic properties of MXenes and their application in electrocatalysis. In particular, we shall systematically discuss their applications into electrical-driven hydrogen production, solar-driven hydrogen production, and nitrogen reduction. This review provides an insightful understanding on the mechanism behind the outstanding performances observed in experiments and calculations, which may guide the design of novel catalysts with high catalytic activities in electrocatalysis. Additionally, a wide range of strategies to design and fabricate new MXenes as electrocatalysts will be discussed to give potential avenues for their commercial applications. Finally, the perspective on the future development is given in the end.

We aimed to investigate the clinical, diagnostic, and imaging features of patients with late onset axial spondyloarthritis (SpA) with initial symptom manifestation aged over 45 years. Participants with axial SpA were consecutively recruited. Clinical, demographic, blood, and imaging parameters were compared between the groups with early (≤45 years) and late onset (45 years) at a cross-sectional level. Logistic regressions were used to determine the independent associations with axial SpA with late onset. A total of 455 participants were recruited. Among them, 70 (15.4%) had late onset disease. Multivariate analyses showed that axial SpA with late onset was associated with higher C-reactive protein based ankylosing spondylitis disease activity index (ASDAS-CRP) (B = 0.10; P = .04), higher intensity of spinal inflammation as measured by maximum apparent diffusion coefficient (spinal ADC max) (B = 0.27; P = .03) and mean ADC (spinal ADC mean) (B = 0.30; P = .004), lower modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) (B = -0.12; P = .02), more tender joint count (B = 0.12; P = .02), and fewer inflammatory back pain (IBP) (OR = 0.26; P.001). Axial SpA with late onset had higher clinical disease activity, higher intensity of spinal MRI inflammation, less radiographic damage, and more tender joint count. There was also less inflammatory back pain, which could make the diagnosis more difficult.

Background Catheter ablation is increasingly employed in the management of atrial fibrillation (AF). Data regarding safety of ablation of AF is largely derived from controlled clinical trials. Objectives The aim of this study was to analyze safety and complications of AF ablation performed in a "real world" setting outside of clinical trials, and obtain insights on predictors of complications. Methods We utilized the National Inpatient Sample database, to identify all patients who underwent AF ablations between 2015 and 2017 using International Classification of Disease-Tenth revision codes. Complications were defined as per the Agency for Health Care Research and Quality Guidelines. Statistical tests including multivariate logistic regression were performed to determine predictors of complications. Results Among 14,875 cases of AF ablation between 2015 and 2017, a total of 1884 complications were identified among 1080 (7.2%) patients. Patients with complications were likely to be older and female with a higher burden of comorbidities. A 27% increase in complications was observed from 2015 to 2017, driven by an increase in pericardial complications. Multivariate regression analysis revealed that pulmonary hypertension (adjusted odds ratio [aOR]: 1.99, p = .041) and chronic kidney disease (CKD; aOR: 1.67, p = .024), were independent predictors of complications. Centers with higher procedural volumes were associated with lower complication rates. Conclusions Complication rates related to AF ablations remain substantially high. Presence of pulmonary hypertension and CKD are predictive of higher procedural complications. Furthermore, hospital procedure volume is an important factor that correlates with complication rates.

Effective science teaching requires a specialised body of knowledge. Researchers have recognised the importance of understanding the incoming knowledge that pre-service science teachers (PSTs) brin...

Critical stability of the metastable bound 2 p 2 3 P e state of two-electron atoms near the critical nuclear charge Z c (smaller than which the bound state ceases to exist) is investigated by employing the explicitly correlated Hylleraas-configuration interaction basis function. Our numerical calculation shows that, when the nuclear charge decreases to Z c , the ionization energy of the system approaches zero linearly and this behavior is fully consistent with the Hellmann–Feynman theorem. Radial and angular physical quantities as well as the inner and outer electron radial density distributions are calculated to reveal the classical geometric structure of the two-electron atom. The inner electron can be well modeled by a hydrogenic model in the 2 p state and its density distribution does not change much as the nuclear charge is changed. The outer electron, which is still localized in a finite region near the nucleus before the system transforms into a well-defined resonance, is shifted notably into a far-distance region. The critical stability of the system near the bound-continuum limit is therefore dominated by the outer electron.

Students need procedural understanding—that is, knowledge of the procedures that scientists use to establish scientific evidence (also known as “concepts of evidence”), to successfully perform scientific investigations, and to evaluate public and scientific claims. However, concepts of evidence are seldom explicitly targeted in routine practical activities in secondary school science classrooms. We describe how a commonly used practical activity, yeast fermentation, can be modified to provide a meaningful context for developing students’ understanding of concepts of evidence associated with measurement, as well as more difficult-to-learn scientific ideas, such as rates of reaction. The modified practical activities give students opportunities to exercise their creativity in assembling setups; brainstorm solutions to design problems in teams; reflect on their decisions related to concepts of evidence associated with measurement when designing their setups; compare the validity and reliability of data produced using different setups; and develop their understanding of difficult-to-learn scientific ideas.

Predictive models for key outcomes of coronavirus disease 2019 (COVID-19) can optimize resource utilization and patient outcome. We aimed to design and internally validate a web-based calculator predictive of hospitalization and length of stay (LOS) in a large cohort of COVID-19-positive patients presenting to the Emergency Department (ED) in a New York City health system. The study cohort consisted of consecutive adult ( 18 years) patients presenting to the ED of Mount Sinai Health System hospitals between March 2020 and April 2020, diagnosed with COVID-19. Logistic regression was utilized to construct predictive models for hospitalization and prolonged ( 3 days) LOS. Discrimination was evaluated using area under the receiver operating curve (AUC). Internal validation with bootstrapping was performed, and a web-based calculator was implemented. From 5859 patients, 65% were hospitalized. Independent predictors of hospitalization and extended LOS included older age, chronic kidney disease, elevated maximum temperature, and low minimum oxygen saturation (p 0.001). Additional predictors of hospitalization included male sex, chronic obstructive pulmonary disease, hypertension, and diabetes. AUCs of 0.881 and 0.770 were achieved for hospitalization and LOS, respectively. Elevated levels of CRP, creatinine, and ferritin were key determinants of hospitalization and LOS (p 0.05). A calculator was made available under the following URL: https://covid19-outcome-prediction.shinyapps.io/COVID19_Hospitalization_Calculator/ . This study yielded internally validated models that predict hospitalization risk in COVID-19-positive patients, which can be used to optimize resource allocation. Predictors of hospitalization and extended LOS included older age, CKD, fever, oxygen desaturation, elevated C-reactive protein, creatinine, and ferritin.

A novel rotational angle microwave sensor with a high dynamic range and sensitivity for detecting angular displacement is presented. It exploits the spectral separation between two notch frequencies or transmission zeros that are generated in its transfer function, and whose value varies as a function of the rotation angle to be measured. The sensor is based on a bi-path transversal-signal-interference (TSI) circuit configuration that is implemented on microstrip technology, where a rotor comprised of an open-circuit-ended stub is loaded onto a stator of this transversal circuit with equal-length electrical paths. The mechanical rotation of the rotor changes the contact point of the open-circuit-ended line to the stator, thus effectively modifying one of the overall paths of the stator and, hence, the inter-transmission-zero separation. Design guidelines for the synthesis of the proposed rotation sensor with a specified dynamic range and sensitivity are provided. Furthermore, a proof-of-concept microstrip-substrate-based prototype with an angular rotation range of 180° is developed at 920 MHz and tested to validate this approach experimentally.

Although professional development (PD) programs often use video, extraneous information during video viewing can distract teachers. We developed a discourse visualization tool, the Classroom Discou...

In recent years, teacher noticing has emerged as a construct to capture the dynamic and situational aspects of teaching expertise that underlies teachers’ in-the-moment teaching decisions and actio...

In this paper, the design methodology of a microstrip angular displacement sensor based on an impedance transformer with a quasi-Chebyshev frequency response is proposed. This sensor with impedance transforming function can realize the angular displacement detection by bandwidth sensing, and matching sensing simultaneously. The insertion loss in stopband achieves 24.9 dB to 32.6 dB with an average bandwidth selectivity of 2.25 MHz/degree of the sensor centered at 2.4 GHz with two poles of 1.71 GHz and 2.81 GHz. Meanwhile, the average matching level of return loss for displacement sensitivity are 0.18 dB/degree and 0.15 dB/degree, respectively. It is the first time to apply an impedance transformer into the angular displacement sensor design for both bandwidth and matching level sensing among reviewed literatures. In this design, the load-to-source impedance transformation is designed for 250-to- $50~\Omega $ , and by adding a rotated stub on the proposed microstrip transformer, the sensing function is developed with angular displacement.

This study investigated the nature of pre-service science teachers’ (PSTs’) situation-specific skills for informal formative assessment (FA) and their awareness of activating these skills in classroom-like situations. Video-based interviews were conducted to collect data from fifteen PSTs before they participated in a teacher education program. Authentic classroom videos capturing evidence of student thinking were used as probes to elicit information on the PSTs’ perceptions, interpretations, and decision-making in various classroom-like situations that afforded opportunities for FA. The findings indicate that the PSTs tended to focus on content-generic evidence and the responses of students in the whole class, to infer student thinking at a non-content specific level, and to propose responses that were vague or devoid of scientific content. On re-exposure to the same evidence of student thinking captured in short video clips, and with more specific prompting questions, more of the PSTs identified content-specific evidence from individual students and interpreted the nuances of student thinking at a content-specific level. Yet, the capacity of the PSTs to propose student-focused instructional moves remained limited. Overall, the findings suggest that the PSTs were not particularly aware of applying their situation-specific skills for informal FA when making on-the-fly teaching decisions in classroom-like situations that offer rich opportunities for FA. This study adds to the existing understanding of PST knowledge/skills for informal FA and provides a mechanism for eliciting and characterizing teachers’ situation-specific skills for informal FA. The implications for initial teacher education are discussed.

Learning science encompasses learning the language of science, which can pose considerable challenges to students due to its specialized features and structures. Addressing the three-language problem (the need to transition between daily, general school and disciplinary languages) and the specific language demands of science thus constitutes part of the larger goal of promoting disciplinary literacy. Most studies have focused on the conceptual demands of science learning and have not examined what knowledge teachers require to support students’ learning of the language of science. In this study, we focus on science teachers’ knowledge of students (KS) for addressing the language demands of science. This qualitative case study has two aims: (1) to unpack a teacher’s KS related to their language use in science and (2) to uncover how this KS informs teaching practices. Transcripts of teacher interviews, lesson planning sessions and lessons drawn from two Grade 4 science classrooms taught by a primary science teacher constituted the data for this study. We identify five aspects of KS (i.e. prior knowledge of and about language, difficulties with language, abilities across modes of language and across subject areas and learning progress) that inform four distinct teaching practices. This case study highlights and unpacks a dimension of KS that is often overlooked in the current literature on pedagogical content knowledge (PCK) for science teaching. The implications to teachers’ PCK, science teaching and teacher professional development are discussed in light of the findings.

A class of angular-displacement microwave sensor based on a microwave signal-interference transversal filtering section (TFS) with unequal-electrical-length paths is reported for the first time. It consists of a bi-path TFS composed of two in-parallel transmission-line segments with distinct lengths, which is modified by adding a rotational open-circuit-ended stub as the rotor to a curved section as the stator of one of its line segments. In this manner, the spectral positions of the transmission zeros, which are produced in its filtering transfer function through destructive signal-energy interactions, are modified with the rotation of this additional stub. This allows single/multi-band angular-displacement microwave-sensing capabilities in terms of transmission-zero inter-spacing variation for passbands/stopbands and stopband-peak-level modification to be attained by means of the mechanical rotation of the rotor. The theoretical operational principles of this type of bi-path-TFS-based angular-displacement microwave sensor and design curves for specific values of its electrical parameters are provided. Moreover, for experimental validation purposes, a proof-of-concept prototype of the devised TFS-based microwave-sensor approach operating at 961 MHz with 180° dynamic range is prototyped in microstrip technology and measured. A comparative analysis of the developed angular-displacement microwave sensor with the state-of-the-art is also presented.

Supplemental material, sj-docx-1-tab-10.1177_1759720X221119250 for MRI lesions in SpA: a comparison with noninflammatory back pain using propensity score adjustment method by Ho Yin Chung, Jin Xian Huang, Kam Ho Lee, Helen Hoi Lun Tsang, Chak Sing Lau and Shirley Chiu Wai Chan in Therapeutic Advances in Musculoskeletal Disease

Supplemental material, sj-docx-1-tab-10.1177_1759720X221119250 for MRI lesions in SpA: a comparison with noninflammatory back pain using propensity score adjustment method by Ho Yin Chung, Jin Xian Huang, Kam Ho Lee, Helen Hoi Lun Tsang, Chak Sing Lau and Shirley Chiu Wai Chan in Therapeutic Advances in Musculoskeletal Disease

Student teachers (STs) were asked to reflect on their experiences of watching videos of their own and their peers’ teaching and to generate and share metaphors of the experience. Qualitative analys...

The frequently-used Z k and Y k functions in the framework of numerical Hartree–Fock method are formulated for atomic systems embedded in weakly-coupled plasmas modeled by Debye–Huckel potential. The Gegenbauer expansion is used to decompose the screened interelectronic Coulomb potential . Two numerical methods , the integration and differentiation ones, are developed to accurately and efficiently calculate the Z k and Y k integrals with each one showing special advantages in the implementation of numerical Hartree–Fock programs. Comparing to the analytical results specialized for Slater-type radial functions, it is generally concluded that the integration method possesses more accuracy and robustness than the differentiation one. Calculations on the two-electron C 4 + ion in three different screening models are performed to demonstrate the applicability and stability of present methods in a wider range of screening parameters than existing Hartree–Fock calculations. With benchmark Hartree–Fock energies obtained in this work and accurate non-relativistic energies calculated based on Hylleraas-CI basis functions, it is found that the correlation energies are smallest in the fully screening model.

Students often bring to biology classrooms ideas that are not in line with scientific thought. Simply telling students that their ideas are wrong does not always help advance their scientific thinking. This article describes a teaching and learning activity that allows secondary biology teachers to elicit, interpret, and address students' misconceptions in a meaningful way. The activity provides a chance for students to discuss their nascent ideas about biology with their peers in a safe and nonthreatening environment. More importantly, the activity engages students in a process of reconsidering their initial ideas through reasoning about why certain ideas are scientifically correct.

Background Despite advances in resuscitation medicine, the burden of in‐hospital cardiac arrest (IHCA) remains substantial. The impact of these advances and changes in resuscitation guidelines on IHCA survival remains poorly defined. To better characterize evolving patient characteristics and temporal trends in the nature and outcomes of IHCA, we undertook a 20‐year analysis of a national database. Methods and Results We analyzed the National Inpatient Sample (1999–2018) using International Classification of Diseases , Ninth Revision and Tenth Revision, Clinical Modification ( ICD‐9‐CM and ICD‐10‐CM ) codes to identify all adult patients suffering IHCA. Subgroup analysis was performed based on the type of cardiac arrest (ie, ventricular tachycardia/ventricular fibrillation or pulseless electrical activity‐asystole). An age‐ and sex‐adjusted model and a multivariable risk‐adjusted model were used to adjust for potential confounders. Over the 20‐year study period, a steady increase in rates of IHCA was observed, predominantly driven by pulseless electrical activity‐asystole arrest. Overall, survival rates increased by over 10% after adjusting for risk factors. In recent years (2014–2018), a similar trend toward improved survival is noted, though this only achieved statistical significance in the pulseless electrical activity‐asystole cohort. Conclusions Though the ideal quality metric in IHCA is meaningful neurological recovery, survival is the first step toward this. As overall IHCA rates rise, overall survival rates are improving in tandem. However, in more recent years, these improvements have plateaued, especially in the realm of ventricular tachycardia/ventricular fibrillation‐related survival. Future work is needed to better identify characteristics of IHCA nonsurvivors to improve resource allocation and health care policy in this area.

Using diffusion-weighted imaging (DWI)-derived apparent diffusion coefficient (ADC), we aimed to determine the relationship between intensity of spinal inflammation and mobility in patients with axial spondyloarthritis (SpA) in early and later stages of active disease. The Ankylosing Spondylitis Disease Activity Score (ASDAS) was also used for a more comprehensive evaluation.Participants with axial SpA and back pain were recruited from 10 rheumatology centers. Clinical, biochemical and radiological parameters were collected. Short tau inversion recovery (STIR) sequence magnetic resonance imaging (MRI) and DWI of the spine and sacroiliac (SI) joints were performed. ADC maps were generated. Participants were examined for Bath Ankylosing Spondylitis Metrology Index (BASMI). Linear regression models were used to determine associations between BASMI and various clinical, radiological, and MRI parameters in participants with active inflammation on spinal ADC maps.One-hundred and twenty-seven participants were included in the analyses. Multivariate linear regression showed that mean ADC spine (ß = .16; P = .03), ASDAS-C-reactive protein (CRP) (ß = .29, P .001), and ASDAS-erythrocyte sedimentation rate (ESR) (ß = .25, P .01) were associated with BASMI. In participants with duration of back pain ≤3 years, mean spine ADC (ß = .37; P = .03), ASDAS-CRP (ß = .44; P = .01), and ASDAS-ESR (ß = .42; P = .01) were associated with BASMI after adjustment for confounding factors. In participants with duration of back pain3 years, only ASDAS-CRP (ß = .25; P .01) and ASDAS-ESR (ß = .20; P = .20) were associated with BASMI.Intensity of inflammation and clinical disease activity were independently associated with impairment of spinal mobility. The associations were stronger in early (≤3 years) than later disease.

Introduction: Several small studies have reported variable outcomes following in-hospital cardiac arrest (IHCA) in patients with COVID-19. A clear estimate is important in prognostication and guiding resuscitation efforts and policies for these patients. Methods: A search of PubMed, Embase, and Scopus databases was conducted to identify studies reporting outcomes after IHCA in adult patients with confirmed COVID-19. The cumulative characteristics of the patients were described. The primary outcome studied was survival at 30 days or at hospital discharge (short term survival). Additional outcomes of interest were proportional prevalence of the initial rhythm at arrest, return of spontaneous circulation (ROSC), and neurological recovery (defined as Cerebral Performance Category Score of 1-2 ). Metanalysis of proportions was performed utilizing the Metaprop command. A random effects model was chosen to account for interstudy variance. Results: A total of 13 eligible studies were identified and included in the analyses. Out of all the hospitalized patients with COVID-19, 1,618 underwent advanced cardiac resuscitation after an IHCA. Patients who had a cardiac arrest had a median age between 50-69 years. IHCA occurred predominantly in men, and in the ICU setting. Shockable rhythms were identified in 8% (95% CI 5-10%, I2; 56%) and non-shockable rhythms in 89% (95% CI 85-94% I2; 84%) of patients (Fig. 1a). ROSC was achieved in 40% (95% CI 31-48% I2; 90%) (Fig. 1b). Only 7 % ( 95% CI 3-12% I2; 86%) of patients survived at 30 days/hospital discharge (Fig. 1c). Neurological recovery was seen in 5% (95% CI 3-9% I2; 67%) of patients who suffered a IHCA (Fig. 1d). Conclusions: Our meta-analysis demonstrates the majority of the cardiac arrests in patients with COVID-19 have non-shockable rhythms. Survival rate in these patients is low, and neurological recovery is unfavorable. This study provides further insight in guiding resuscitation efforts in these patients.

The kinetically and atomically balanced conditions have been extensively used in various basis-set expansion methods to remove the nonphysical spurious states appearing in the numerical calculation of the Dirac equation; however, they are generally not applicable for methods in discrete variable representation. In this paper we show that these conditions can be conveniently introduced into the generalized pseudospectral (GPS) method. Four types of balanced condition, the mono kinetic balance (MKB), dual kinetic balance, mono atomic balance (MAB), and dual atomic balance, are incorporated into the GPS method to eliminate the spurious states. Numerical calculations for a variety of bound states of H-like ions in point-charge models are compared with the analytical solutions to demonstrate the accuracy and efficiency of the developed methods. The application to highly charged ions with extended nuclear models is performed to show the flexibility of the balanced GPS methods in practical atomic structure calculations. It is concluded that the MAB-GPS and MKB-GPS methods, which are both free of any spurious states, show better performance and simpler implementation than the others in solving the Dirac equation with the potential in point-charge and extended nuclear models, respectively. The balanced GPS methods developed in this paper provide a useful tool for accurately solving the one-electron Dirac equation and efficiently constructing the multielectron relativistic wave functions.

We develop an efficient numerical method to directly calculate the critical screening parameters for one-electron systems with Hulthén and Debye–Hückel screened Coulomb potentials (SCPs). Compared to indirect methods, which locate the critical screening parameters via searching the potential parameters with near-zero energy, the method developed in this work directly calculates the critical screening parameters as eigenvalues of a generalized eigenvalue problem. This feature allows us to simultaneously determine the critical parameters for bound states from low-lying excitation to high-lying Rydberg limit with high accuracy. The method is applied to SCPs to investigate the asymptotic behavior of critical screening parameters as the principal quantum number n approaches infinity. It has been shown that the critical screening parameters in Hulthén and Debye–Hückel potentials follow the 2n −2 and 4n −2/π asymptotic laws, respectively, and that the orbital angular momentum affects the higher-order coefficients linearly.