cssi/SciSciGPT-SciSciNet huggingface dataset:
Control Design for a Hybrid Dynamic System: A NASA Life Support System

We consider the control problem of a Variable Configuration CO2 Removal system (VCCR), which exhibits a hybrid dynamical character due to the various configurations/modes in which one could operate the system. The VCCR is part of an overall Air Recovery System of an intended human life-support system for space exploration. The objective of the control problem is to track a desired concentration profile of CO2 in a crew cabin while also ensuring safety in terms of keeping the CO2 and O2 concentrations in the crew cabin within permissible bounds. We present a mathematical programming based control synthesis formulation, as well as a simulation-based hybrid feedback controller. We exploit the problem structure and map the hybrid optimization problem onto a continuous nonlinear program with the aid of an appropriate representation of time and set definitions. We also discuss case studies showing the performance of these controllers during off-nominal and failure conditions.
Functional Connectivity of the Brain: Reconstruction from Static and Dynamic Data

The central nervous system is a single complex network connecting each neuron through a number of synaptic connections. However, only a small fraction of the total connections functionally link neurons together. If the smallest multineuronal architecture within which functional links are established constitutes circuitry, then what are the basic operating principles of these circuitries from which we can understand both the composition and the dynamics of the larger networks? We argue that a finite class of circuitries, the “basic circuitries,” can be identified as repeating structural motifs tightly associated with specific dynamics. Functional circuitries, however, cannot be derived from the static architecture simply because they do not obey structural borders. Fortunately, since the constituent neurons do act in synergy, we can infer from the dynamics the minimal structural conditions that constitute a circuitry. In this chapter, instead of giving a precise definition of the “basic circuitry,” we outline a set of methods that may elucidate such a definition. We argue that since the concept of circuitry incorporates both dynamic and static features, understanding can be achieved through combining the structural and dynamic aspects of the available data. We review methods of extracting functional information from static data first. Next, we review methods of extracting structural information from dynamic data. Ideally, these two approaches should converge and define circuitry based on the fragile concept of functional connectivity.
A randomized comparison of fixed power and temperature monitoring during slow pathway ablation in patients with atrioventricular nodal reentrant tachycardia.

Temperature monitoring may be helpful for ablation of accessory pathways, however its role in ablation of atrioventricular nodal reentrant tachycardia (AVNRT) using the slow pathway approach is unclear. Therefore, the purpose of this study was to prospectively compare slow pathway ablation for AVNRT using fixed power or temperature monitoring. The study included 120 patients undergoing ablation for AVNRT. Patients were randomly assigned to receive either fixed power at 32 watts, or to temperature monitoring with a target temperature of 60°C. The primary success rate was 72% in the fixed power group and 95% in the temperature monitoring group (p=0.001). The ablation procedure duration (35±29 min vs 35±30 min; p=0.9), fluoroscopic time (32±17 vs 35±19 min; p=0.4), mean number of applications (10.2±8.1 vs 8.4±7.9; p=0.2), and coagulum formation per application (0.2% vs 0.5%; p=0.6) were statistically similar in the fixed power and temperature monitoring groups, respectively. The mean temperature (47.3±4.8°C vs 48.6±3.8°C; p<0.01), and the temperature associated with junctional ectopy (48.2±3.8°C vs 49.3±3.6°C, p<0.01) were less for the fixed power than the temperature monitoring group. In the temperature monitoring group, only 31% of applications achieved an electrode temperature of 60°C. During follow up of 6.6±3.6 months there were two recurrences in the fixed power group and one in the temperature monitoring group (p=1.0). In summary, power titration directed by temperature monitoring was associated with an improved primary procedural success rate. Applications of energy were associated with a temperature of approximately 50°C with both techniques, suggesting that there is a low efficiency of heating in the posterior septum.
Adapting a religious health fatalism measure for use in Muslim populations

Objective Fatalism has been shown to influence health behaviors and outcomes among different populations. Our study reports on the adaptation of the Religious Health Fatalism Questionnaire for a Muslim population (RHFQ-M). Design The original RHFQ wording was modified for a Muslim context and cognitively tested in 6 focus groups (FG). Items were revised by Muslim and non-Muslim healthcare researchers based on FG responses regarding the theological “accurateness” of the questions. The revised 9-item measure was administered to 58 English-speaking Muslim women (≥40 years old) recruited from two mosques in the Chicago area in order to assess psychometric properties. Main outcome measures Cronbach’s alpha and exploratory factor analyses were used to assess internal consistency and measure dimensionality, respectively. Statistical correlations with several fatalism and religiosity measures were computed to assess convergent and discriminant validity. Results After testing with an ethnically and racially diverse group of Muslims, the RHFQ-M was found to be reliable (Cronbach’s α is 0.79), comprised of two distinct underlying subscales, and is correlated with, but distinct from, other measures of fatalism and Islamic religiosity. Conclusion Our adapted measure, RHFQ-M, appears to accurately assess Islamic dimensions of fatalism and is ready for use in the health literature.
Involuntary Psychotropic Treatment in the Correctional System: Revisiting the Legal Standards.

Correctional facilities are obligated to provide psychotropic medications, as part of standard psychiatric care, to inmates with serious mental illness. The right to refuse such medication treatmen...
Dyadic connections in the context of group mentoring: A social network approach.

Aims The aim of this study was to examine how relational ties among all participants in a group mentoring program related to connections within assigned mentor-mentee dyads. Methods College student female mentors (n = 54) and middle school-aged female mentees ( n = 65) in eight mentoring groups completed social network surveys on multiple occasions, rating all groupmates on connection and effort to reach out. Results Hierarchical linear models (participants nested in groups) revealed mentors who were rated as being highly connected to multiple mentees had stronger connections within their dyad. For mentees, high ratings on efforts to reach out to others related to the stronger dyadic connection. Mentees reported lower dyadic connection in groups with more segregation by role. Conclusion Results suggest group dynamics matter for one-on-one mentoring relationships, but how they matter differs by role. Implications for the use of social network analysis to assess complex settings are discussed.
Whole blood RNA sequencing reveals a unique transcriptomic profile in patients with ARDS following hematopoietic stem cell transplantation

The acute respiratory distress syndrome (ARDS) is characterized by the acute onset of hypoxemia and bilateral lung infiltrates in response to an inciting event, and is associated with high morbidity and mortality. Patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT) are at increased risk for ARDS. We hypothesized that HSCT patients with ARDS would have a unique transcriptomic profile identifiable in peripheral blood compared to those that did not undergo HSCT. We isolated RNA from banked peripheral blood samples from a biorepository of critically ill ICU patients. RNA-Seq was performed on 11 patients with ARDS (5 that had undergone HSCT and 6 that had not) and 12 patients with sepsis without ARDS (5 that that had undergone HCST and 7 that had not). We identified 687 differentially expressed genes between ARDS and ARDS-HSCT (adjusted p-value < 0.01), including IFI44L, OAS3, LY6E, and SPATS2L that had increased expression in ARDS vs. ARDS-HSCT; these genes were not differentially expressed in sepsis vs sepsis-HSCT. Gene ontology enrichment analysis revealed that many differentially expressed genes were related to response to type I interferon. Our findings reveal significant differences in whole blood transcriptomic profiles of patients with non-HSCT ARDS compared to ARDS-HSCT patients and point toward different immune responses underlying ARDS and ARDS-HSCT that contribute to lung injury.
Student assessment of narrative: telling stories in the classroom

ABSTRACTWe conducted this study to create a measure of instructional narratives and to validate the new instrument by assessing its construct validity. In particular, we created an item pool reflec...
Enhanced recovery after surgery pathway for patients undergoing abdominal wall reconstruction.

Abstract Background Pathways of enhanced recovery after surgery represent a standardized, multimodal approach to postoperative care with the goal of accelerating recovery without increasing morbidity. We hypothesized that implementation of an enhanced recovery after surgery pathway for abdominal wall reconstruction would result in a decreased duration of stay. Methods We compared 100 historic controls to 100 consecutive patients undergoing abdominal wall reconstruction with use of a newly implemented, enhanced recovery after surgery pathway to detect a difference in duration of stay of 1 day. Groups were compared on demographics and clinical characteristics using χ2, Fisher exact, Mann-Whitney U test, and 2 sample t tests as appropriate for the data. Results There was no change in duration of stay with the enhanced recovery after surgery protocol (median 5 vs 5 days, P = .78). There was no difference in time to regular diet (median 3 vs 3 days, P = .14). There was a trend toward decreased time epidurals or patient-controlled analgesia used (median 3 vs 3 day, P = .01). There was no increase in readmission rates. In a subgroup analysis, factors associated with a duration of stay Conclusion Our enhanced recovery after surgery study group did not show a decrease in duration of stay. Although smaller hernia defects, lesser operative times, and better baseline quality-of-life scores were associated with shorter duration of stay, the benefits of enhanced recovery after surgery seem limited in patients with the more complex hernia repairs.
Point-of-Care Procedure for Enhancement of Meniscal Healing in a Goat Model Utilizing Infrapatellar Fat Pad-Derived Stromal Vascular Fraction Cells Seeded in Photocrosslinkable Hydrogel.

Background:Large radial tears of the meniscus involving the avascular region can compromise meniscal function and result in poor healing and subsequent osteochondral degeneration. Augmentation of s...
Using Ambulatory Assessments to Understand Personality-Health Associations

The assessment of personality is moving beyond typical questionnaire assessments and beginning to rely on repeated assessments where people respond multiple times a day for multiple days. These ambulatory assessments open up new avenues of research directly relevant to understanding healthy aging. In this chapter, two underutilized methods are discussed. First, dynamic metrics of personality, such as variability in behavior, inertia, and synchronicity, are likely to be related to healthy aging over and above standard mean-level trait assessments. These assessments can further allow better tests of personality processes, such as person-situation transactions, given that assessments are collected in situ rather than collapsed across time and context. Second, ambulatory assessments allow personality to be assessed at an idiographic level, where personality is defined not by comparison to others but how each person has a structure of personality unique to them. These idiographic assessments are likely better suited to identify which components of personality are linked to health processes.
Clinical and Imaging Features of Contrast-induced Neurotoxicity After Neurointerventional Surgery

Background Contrast-induced neurotoxicity (CIN) is an infrequent complication of endovascular procedures, and its understanding remains poor. We aimed to study and characterize the clinical and imaging features of a case series of CIN after neurointerventional surgery. Methods We reviewed all neuroendovascular consecutive procedures from September 2014 to November 2018. CIN was defined as new onset of neurologic deficits that occurred postoperatively after excluding other conditions. All demographic, clinical, procedural, and radiologic data were retrospectively analyzed and collected. Results Eleven cases of CIN in 1587 patients were identified out of 2510 procedures. The median age was 76 years (interquartile range [IQR], 65–81). The most common comorbidity was hypertension (82%). Median procedure time was 100 minutes (IQR, 80–130.5 minutes). All patients showed wide variability in intraprocedural blood pressure (BP) recordings with fluctuations from the baseline BP. Systolic BP ranged from 83 mm Hg below the patient baseline to 80 mm Hg above baseline. The median symptom onset was 4 hours (IQR, 0.8–9.5 hours). The CIN signs and symptoms presented gradually, initially with encephalopathy and later with focal signs. All patients had an initial computed tomography scan, which showed ipsilateral cerebral edema in 82% of patients. Two had contrast enhancement. Complete resolution of CIN symptoms was obtained in a median time of 3 days (IQR, 2.5–3 days). Conclusions CIN should be considered in the context of the progressive onset of neurologic deficits after neuroendovascular procedures. A distinct imaging pattern of ipsilateral hemisphere edema in the absence of ischemia is usually identified. Variability in procedural BP might be a predisposing factor.
Late onset infectious complications and safety of tocilizumab in the management of COVID-19.

BACKGROUND: Tocilizumab (TCZ) has been used in the management of COVID-19-related cytokine release syndrome (CRS). Concerns exist regarding the risk of infections and drug-related toxicities. We sought to evaluate the incidence of these TCZ complications among COVID-19 patients. METHODS: All adult inpatients with COVID-19 between 1 March and 25 April 2020 that received TCZ were included. We compared the rate of late-onset infections (>48 hours following admission) to a control group matched according to intensive care unit admission and mechanical ventilation requirement. Post-TCZ toxicities evaluated included: elevated liver function tests (LFTs), GI perforation, diverticulitis, neutropenia, hypertension, allergic reactions, and infusion-related reactions. RESULTS: Seventy-four patients were included in each group. Seventeen infections in the TCZ group (23%) and 6 (8%) infections in the control group occurred >48 hours after admission (P = .013). Most infections were bacterial with pneumonia being the most common manifestation. Among patients receiving TCZ, LFT elevations were observed in 51%, neutropenia in 1.4%, and hypertension in 8%. The mortality rate among those that received TCZ was greater than the control (39% versus 23%, P = .03). CONCLUSION: Late onset infections were significantly more common among those receiving TCZ. Combining infections and TCZ-related toxicities, 61% of patients had a possible post-TCZ complication. While awaiting clinical trial results to establish the efficacy of TCZ for COVID-19 related CRS, the potential for infections and TCZ related toxicities should be carefully weighed when considering use.
The Ubiquitin System and A20: Implications in Health and Disease:

Inflammation is triggered by stimulation of innate sensors that recognize pathogens, chemical and physical irritants, and damaged cells subsequently initiating a well-orchestrated adaptive immune response. Immune cell activation is a strictly regulated and self-resolving process supported by an array of negative feedback mechanisms to sustain tissue homeostasis. The disruption of these regulatory pathways forms the basis of chronic inflammatory diseases, including periodontitis. Ubiquitination, a covalent posttranslational modification of target proteins with ubiquitin, has a profound effect on the stability and activity of its substrates, thereby regulating the immune system at molecular and cellular levels. Through the cooperative actions of E3 ubiquitin ligases and deubiquitinases, ubiquitin modifications are implicated in several biological processes, including proteasomal degradation, transcriptional regulation, regulation of protein-protein interactions, endocytosis, autophagy, DNA repair, and cell cycle regulation. A20 (tumor necrosis factor α-induced protein 3 or TNFAIP3) is a ubiquitin-editing enzyme that mainly functions as an endogenous regulator of inflammation through termination of nuclear factor (NF)-κB activation as part of a negative feedback loop. A20 interacts with substrates that reside downstream of immune sensors, including Toll-like receptors, nucleotide-binding oligomerization domain-containing receptors, lymphocyte receptors, and cytokine receptors. Due to its pleiotropic functions as a ubiquitin binding protein, deubiquitinase and ubiquitin ligase, and its versatile role in various signaling pathways, aberrant A20 levels are associated with numerous conditions such as rheumatoid arthritis, diabetes, systemic lupus erythematosus, inflammatory bowel disease, psoriasis, Sjogren syndrome, coronary artery disease, multiple sclerosis, cystic fibrosis, asthma, cancer, neurological disorders, and aging-related sequelae. Similarly, A20 has recently been implicated as an essential regulator of inflammation in the oral cavity. This review presents information on the ubiquitin system and regulation of NF-κB by ubiquitination using A20 as a representative molecule and highlights how the dysregulation of this system can lead to several immune pathologies, including oral cavity-related disorders mainly focusing on periodontitis.
Chiropractic associated vertebral artery dissection: An analysis of 34 patients amongst a cohort of 310.

Abstract Background Vertebral artery dissections (VAD) are a rare but important cause of ischemic stroke, especially in younger patients. Many etiologies have been identified, including MVAs, cervical fractures, falls, physical exercise, and cervical chiropractic manipulation. The goal of this study was to investigate the subgroup of patients who suffered a chiropractor-associated injury and determine how their prognosis compared to other-cause VAD. Methods We conducted a retrospective chart review of 310 patients with vertebral artery dissections who presented at our institution between January 2004 and December 2018. Variables included demographic data, event characteristics, treatment, radiographic outcomes, and clinical outcomes measured using the modified Rankin Scale. Findings Overall, 34 out of our 310 patients suffered a chiropractor-associated injury. These patients tended to be younger (p = 0.01), female (p = 0.003), and have fewer comorbidities (p = 0.005) compared to patients with other-cause VADs. The characteristics of the injuries were similar, but chiropractor-associated injuries appeared to be milder at discharge and at follow-up. A higher proportion of the chiropractor-associated group had injuries in the 0–2 mRS range at discharge and at 3 months (p = 0.05, p = 0.04) and no patients suffered severe long-term neurologic consequences or death (0% vs. 9.8%, p = 0.05). However, when a multivariate binomial regression was performed, these effects dissipated and the only independent predictor of a worse injury at discharge was the presence of a cervical spine fracture (p Interpretation Chiropractor-associated injuries are similar to VADs of other causes, and apparent differences in the severity of the injury are likely due to demographic differences between the two populations.
Violations of Price-Time Priority and Implications for Market Quality

Using a proprietary dataset of a market maker’s limit orders and order acknowledgments timestamped to the nanosecond, we explore the consistency and reliability of an exchange’s price-time priority in practice. We find a high degree of variability in acknowledgment times, and we find that the proportion of times in which the first order entered is also first to be acknowledged is surprisingly low when consecutive orders are placed at very high frequencies. Furthermore, we provide suggestive evidence of impaired market quality in the form of: (i) excess messaging, and (ii) unabsorbed end-of-day order imbalance as a result.
Power Laws In Unions, Churches, and Street Gangs

Power law distributions, in which one quantity varies in proportion to another by some constant, are ubiquitous in nature, but they are also remarkably prevalent in human society. In this paper I demonstrate that labor union, church, and street gang memberships tend towards a power law distribution, lending support for the thesis that group membership is driven by interpersonal connections that place an upper bound on the number of connections any one person may have. If so, then the rise, and decline, of human groups may be successfully modeled.
Utilization of HIV testing and counselling services by women with disabilities during antenatal care in Uganda: analysis of 2016 demographic and health survey.

Background HIV testing and counselling during antenatal care (ANC) is critical for eliminating mother-to-child transmission of HIV. We investigated disparity in utilization of HIV testing and counselling services (HTC) between women with and without disabilities in Uganda. Methods We conducted a retrospective study using the nationally representative 2016 Uganda Demographic and Health Survey. The study sampled 10,073 women between age 15-49 who had a live birth in the last 5 years. We estimated unadjusted and adjusted odds ratio for receiving pre-test HIV counselling, obtaining an HIV test result, and post-test HIV counselling by disability status using logistic regressions. Results We found that women with disabilities were less likely to receive pre-test HIV counselling (59.6 vs 52.4), obtain an HIV test result (68.2 vs 61.4), receive post-test HIV counselling (55.5 vs 51.6), and all HTC services (49.2 vs 43.5). From the regression analysis, women with disabilities were less likely to receive pre-test counselling [AOR = 0.83; CI = 0.74, 0.93] and obtain an HIV test result [AOR = 0.88; CI = 0.78, 0.99]. Conclusions Our findings revealed that women with disabilities are less likely to receive HTC service during ANC and highlighted the need for disability-inclusive HIV and reproductive health services. Government, non-governmental organizations, and other stakeholders should consider funding inclusive campaigns and identifying other mechanisms for disseminating health information and behavioral interventions to women with disabilities.
Combined description of polymer PVT and relaxation data using a dynamic "SL-TS2" mean-field lattice model.

We develop a combined model to describe the pressure–volume–temperature (PVT) thermodynamics and the α- and β-relaxation time dynamics in glass-forming amorphous materials. The PVT results are described using a two-state modification of the Sanchez–Lacombe equation of state (SL-EoS). The minimization of the Sanchez–Lacombe free energy expression allows one to calculate the density (or specific volume) and the “solid fraction” as a function of temperature and pressure. The solid fraction, ψ(T,P), is then substituted into the TS2 mean-field model (V. V. Ginzburg, Soft Matter, 2020, 16, 810), and the equilibrium relaxation times and the glass transition temperature are calculated. Finally, we use a dynamic model of a Tool–Narayanaswami–Moynihan (TNM)-type to describe the density relaxation as a function of the cooling rate. We applied the new framework to describe experimental data for polystyrene and poly(methylmethacrylate) and found a good qualitative and quantitative agreement.
Origins of the concept of store-operated calcium entry.

Abstract The concept of capacitative or store-operated calcium entry, a process by which the release of stored calcium signals the opening of plasma membrane calcium channels, has its roots in the late 1970's, and was formalized in 1986. This short introduction to the current volume of Frontiers in Bioscience briefly summarizes the early experimental work that led to the idea of store-operated calcium entry, and provided the initial proofs for it.
Multi-vehicle convoy mobility in severe terrain conditions: Factor impact analysis, estimation and control strategy

Abstract Military vehicle convoys are logistical supply chains that are heavily relied upon and are very often operated in severe terrain conditions. As it is shown in this article, the convoy mobility analytical estimation becomes a rather difficult task since the track, and thus tire–terrain interaction, is formed by multiple vehicles of a convoy driving over the same track. Furthermore, the distribution of power between the drive wheels of each convoy vehicle is a key factor in convoy mobility enhancement. A vehicle can be immobilized due to inappropriate combination of a power supply to a wheel and its poor tire–terrain properties. This leads to mobility loss of several or all the vehicles of the convoy. To the contrary, power wheel distributions concerted with wheel–terrain conditions improve mobility of a wheel, vehicle and the entire convoy. This article crystallizes the main factors that impact convoy mobility, discusses the factors at a descriptive level of vehicle dynamics control and then results in a convoy on-line mobility estimation and control strategy.
Another application of Rolles's theorem.

We find an analogue of Rolle's Theorem in (real variable) calculus for continuous complex valued functions defined on convex subsets of the complex plane.
Predictors of incidental gallbladder cancer in patients undergoing cholecystectomy for benign gallbladder disease

Background and Objectives Discovery of incidental gallbladder cancer (IGC) has become more frequent due to adoption of laparoscopy. Gallbladder spillage during operation can disseminate cancer and worsen the prognosis. Methods Patients who underwent laparoscopic or open cholecystectomy for benign gallbladder disease January 1996 to August 2011 at two tertiary care facilities were reviewed. Unmatched controls were randomly selected in 2:1 ratio. Preoperative variables were compared between the two groups. Results Sixty-seven patients with IGC were identified and compared to 134 controls. Mean age was 68 for index cases and 49 for controls; 70% of cases and 75% of controls were female. Multivariate analysis showed that higher risk of IGC was significantly associated with age ≥ 65 (OR = 10.61, P < 0.0001), dilated bile ducts (OR = 4.76, P = 0.0028), and presence of gallbladder wall thickening (OR = 4.39, P = 0.0003). This model yielded a very good area under the curve of receiver operating characteristic (AUC = 0.83) for discriminating the patients with IGC from controls. Conclusions IGC is more likely to be found in patients when age is ≥65, with dilated bile ducts and gallbladder wall thickening. Preoperative suspicion of gallbladder cancer should prompt the surgeon to be more careful not to perforate the gallbladder during laparoscopic approach, and to have a lower threshold for conversion if necessary. J. Surg. Oncol. 2013;107:118–123. © 2012 Wiley Periodicals, Inc.
An Equivalent Circuit Model for Ba0.5Sr0.5TiO3-Based Capacitors

In order to integrate a ferroelectric-based device into a larger circuit, one must create an equivalent circuit model for the device. Ferroelectric materials contain a number of complicated parameters that make this task far from trivial. In a Ba0.5Sr0.5TiO3-based capacitor, for example, the capacitance and leakage current vary with applied voltage, temperature and frequency. In addition, at high frequencies the equivalent series inductance and resistance (ESL and ESR) become non-negligible. All of these factors must be understood and quantified in order to create a working circuit. Such an analysis is reported for capacitors fabricated from Pt/BST/Pt films.
Social skills training in the rehabilitation of patients with traumatic closed head injury.

Abstract This research used a traditional social skills training program in the remediation of documented social behavior deficits of severely head-injured persons. More than two years after injury, four severely head-injured persons participated in a skills training program with five components: (1) instruction in the rationale for modifying target behaviors, (2) modeling the correct form of the behaviors, (3) behavioral rehearsal, (4) videotape feedback on performance, and (5) social reinforcement of correct behaviors. The research design was a multiple baseline across behaviors design with four replications. Three patients showed clear treatment effects with evidence of generalization across situations and maintenance of gains at follow-up one year later, thus supporting the applicability of social skills training to this cognitively impaired population.
The foreign policy of Lyndon B. Johnson: the United States and the world, 1963–69

Jonathan Colman, Edinburgh, Edinburgh University Press, 2010, viii+231 pp Commenting on the ‘difficulty’ of evaluating modern presidents, Arthur Schlesinger, Jr. in 1997 singled out Lyndon Johnson ...
On the Outcome Project.

In 1910, Abraham Flexner examined the chaotic state of undergraduate medical education and offered a transformative standardization of admission requirements and educational pedagogy [1]. While inculcation of medical knowledge and patient care were central issues of concern, medical professionalism and public faith had been eroded substantially by inconsistent standards of training. By the late ’90s, medical educators became concerned that the post-graduate apprenticeship system that complemented the Flexner/Hopkins model had become antiquated. Patients and payers demanded greater accountability and more transparent, reproducible metrics of educational achievement to complement needs of the health care system. This manuscript briefly describes Flexner’s revolution in undergraduate medical education and presents firsthand accounts of Drs. David Leach, Susan Swing, and Paul Batalden, who led similarly transformative renovations of graduate medical education (GME) in the new millennium.
Criterion of Crack Resistance of Corrosion Damaged Concrete in Plane Stress State

Abstract A criterion of crack resistance corrosion damaged concrete in plane stress state with colmatation transformation of the concrete structure is built in the coordinate system of the principal normal stresses. Criterion of crack resistance is described by the elliptic curve typical dimensions of which are determined by the kinetics parameters of corrosion damage progress in time and by depth of damages, level and sign of the stress state. This criterion allows taking into account changes in the structure of concrete at various kinds of stress state (tension - tension, compression - compression and tension - compression) with respect to the characteristic types of possible cracks in plane stressed elements. The resulting criterion is quite general and can be used not only for the evaluation of crack resistance for plane stressed concrete and reinforced concrete elements, as well as for solving problems of exposure of residual resource and survivability of exploited reinforced concrete structures under the simultaneous display of force and environmental impacts over time.
High-resolution prediction of soil available water content within the crop root zone

Summary A detailed understanding of soil hydraulic properties, particularly soil available water content (AWC) within the effective root zone, is needed to optimally schedule irrigation in fields with substantial spatial heterogeneity. However, it is difficult and time consuming to directly measure soil hydraulic properties. Therefore, easily collected and measured soil properties, such as soil texture and/or bulk density, that are well correlated with hydraulic properties are used as proxies to develop pedotransfer functions (PTF). In this study, multiple modeling scenarios were developed and evaluated to indirectly predict high resolution AWC maps within the effective root zone. The modeling techniques included kriging, co-kriging, regression kriging, artificial neural networks (NN) and geographically weighted regression (GWR). The efficiency of soil apparent electrical conductivity (ECa) as proximal data in the modeling process was assessed. There was a good agreement (root mean square error (RMSE) = 0.052 cm3 cm−3 and r = 0.88) between observed and point prediction of water contents using pseudo continuous PTFs. We found that both GWR (mean RMSE = 0.062 cm3 cm−3) and regression kriging (mean RMSE = 0.063 cm3 cm−3) produced the best water content maps with these accuracies improved up to 19% when ECa was used as an ancillary soil attribute in the interpolation process. The maps indicated fourfold differences in AWC between coarse- and fine-textured soils across the study site. This provided a template for future investigations for evaluating the efficiency of variable rate irrigation management scenarios in accounting for the spatial heterogeneity of soil hydraulic attributes.
A Large Population-Based Follow-Up Study of Trimethoprim-Sulfamethoxazole, Trimethoprim, and Cephalexin for Uncommon Serious Drug Toxicity

We conducted a population-based 45-day follow-up study of 232,390 people who were prescribed trimethoprim-sulfamethoxazole (TMP-SMZ), 266,951 prescribed trimethoprim alone, and 196,397 prescribed cephalexin, to estimate the risk of serious liver, blood, skin, and renal disorders resulting in referral or hospitalization associated with these drugs. The results were based on information recorded on office computers by selected general practitioners in the United Kingdom, together with a review of clinical records. The risk of clinically important idiopathic liver disease was similar for persons prescribed TMP-SMZ (5.2/100,000) and those prescribed trimethoprim alone (3.8/100,000). The risk for those prescribed cephalexin was somewhat lower (2.0/100,000). Only five patients experienced blood disorders, one of whom was exposed to TMP-SMZ; of seven with erythema multiforme and Stevens-Johnson syndrome, four were exposed to TMP-SMZ. The one case of toxic epidermal necrolysis occurred in a patient who took cephalexin. Finally, only five cases of acute parenchymal renal disease occurred, none likely to be caused by a study drug. We conclude that the risk of the serious diseases studied is small for the three agents, and compares reasonably with the risk for many other antibiotics.
A Tension Leg Floating Platform

The tension leg platform is a new platform concept which is being developed for the Hutton Field in the U.K. sector of the North Sea. The Hutton TLP is a floating drilling and production platform attached by vertical tension legs to piled foundation templates on the sea bed. The deck supports all drilling and production facilities for ballasting, liquid consumables and tension leg anchorages, This paper describes the functional requirements, platform configuration and mooring system. Methods of analysis and structural design considerations including the influence of construction and marine operation requirements on the configuration are discussed.
Molecular modeling of the reaction pathway and hydride transfer reactions of HMG-CoA reductase.

HMG-CoA reductase catalyzes the four-electron reduction of HMG-CoA to mevalonate and is an enzyme of considerable biomedical relevance because of the impact of its statin inhibitors on public health. Although the reaction has been studied extensively using X-ray crystallography, there are surprisingly no computational studies that test the mechanistic hypotheses suggested for this complex reaction. Theozyme and quantum mechanical (QM)/molecular mechanical (MM) calculations up to the B3LYP/6-31g(d,p)//B3LYP/6-311++g(2d,2p) level of theory were employed to generate an atomistic description of the enzymatic reaction process and its energy profile. The models generated here predict that the catalytically important Glu83 is protonated prior to hydride transfer and that it acts as the general acid or base in the reaction. With Glu83 protonated, the activation energies calculated for the sequential hydride transfer reactions, 21.8 and 19.3 kcal/mol, are in qualitative agreement with the experimentally determined...
Parallel Synthesis and High Throughput Dissolution Testing of Biodegradable Polyanhydride Copolymers

We have demonstrated that polycondensation reactions can be carried out in a combinatorial fashion and that the polymer library can be screened at high throughput using a rapid prototyping technique to fabricate multiwell substrates. A linearly varying compositional library of 100 different biodegradable polyanhydride random copolymers that are promising carriers for controlled drug delivery was designed, fabricated, and characterized by IR microscopy within a few hours. The polyanhydride copolymer library was based on 1,6-bis(p-carboxyphenoxy)hexane (CPH) and sebacic anhydride (SA) and was characterized with infrared microspectroscopy to determine the composition within each well. Since degradation and release rates depend on copolymer composition, we also developed new high-throughput methods to investigate drug release from this library of copolymers by designing specific wells for each task. A subset of this library was chosen, and a substrate was designed and fabricated to enable the synthesis and mo...
Validity of an illness severity measure for headache in a population sample of migraine sufferers.

The headache impact questionnaire (HImQ) is used to measure pain and activity limitations from headache over a 3-month recall period. In a prior study, the test-retest reliability of the eight-item HImQ score was found to be relatively high (0.86). In the current study, we examined the validity of the eight-item HImQ by comparing the overall score and individual items to equivalent measures from a 90-day diary. Pain and activity limitations due to headache were assessed in a population-based sample of 132 migraine headache sufferers enrolled in a 90-day daily diary study who completed the HImQ at the end of the study. The HImQ score was derived from four frequency-based questions (i.e. number of headaches, missed days of work, missed days of chores, or missed days of non-work activity) and four summary measures of average experience across headaches (i.e. average pain intensity, and average reduced effectiveness when having a headache at work, during household chores, and in non-work activity). Diary based measures were used as the gold standard in evaluating the HImQ score. Mean and median values of frequency-based HImQ items (e.g. number of headaches) were similar to equivalent diary measures, indicating no systematic bias. In contrast, HImQ measures of average experience across attacks (e.g. average pain intensity) overestimated equivalent diary measures and, in general, better approximated diary measures for migraine headaches, rather than all headaches. The highest correlations between HImQ and diary items were observed for headache frequency and average pain intensity, the two general headache measures, followed by measures of reduced effectiveness. Among frequency-based measures, the strength of the correlation was directly related to the magnitude of the mean. The higher the mean value, the higher the correlation. The correlation between the HImQ score and diary based score was 0.49. The HImQ score is moderately valid. Frequency-based items (e.g. number of missed work days) were found to be unbiased and the highest correlation coefficients were observed for frequency-based items with relatively high mean counts (number of headaches, number of missed non-work days). These findings have implications for measuring severity of chronic episodic conditions like headache, asthma, back pain, arthritis, epilepsy, and panic disorder, which can cause limitations to activities. The validity of illness severity measures may be improved by using frequency-based questions to assess both missed activity days and days with significantly reduced effectiveness or productivity (e.g. by 50% or more). By combining the count for both missed days and days where productivity is substantially reduced, the mean of the frequency-based measure will be increased, a factor which may improve the overall validity of the item. A severity measure can be derived from such items by simple addition and provides a scale with intuitively meaningful units.
Endovascular versus Open Repair of Popliteal Artery Aneurysms: Outcomes in the US Medicare Population

OBJECTIVE The management of popliteal artery aneurysms (PAAs) has undergone significant transition from open surgery to endovascular graft placement with few longitudinal data evaluating outcomes. METHODS The Centers of Medicare & Medicaid Services Inpatient claims (2005-2007) were queried with a diagnosis of lower extremity artery aneurysm in association with elective Current Procedural Terminology codes for open (OPEN group) and endovascular (ENDO group) repair. RESULTS A total of 2962 patients were identified. Endovascular interventions significantly increased over the time of the study (11.7% vs 23.6%, P < .0001). Overall complication rates for OPEN and ENDO groups did not differ significantly (11.3% vs 9.3%; P = .017). No differences in the 30- and 90-day mortality rates were found between OPEN versus ENDO groups. The ENDO group had greater 30- and 90-day reinterventions (4.6% vs 2.1%, P = .001 and 11.8% vs 7.4%, P = .0007, respectively). Length of stay (4.5 days vs 2.5 days, P < .0001) and charges ($43 180 vs $35 540, P < .0001) were greater for OPEN group. CONCLUSION Despite a significant increase in the utilization of endovascular repair of PAAs, endovascular repair was associated with greater reinterventions over time and did not offer a mortality or cost benefit.
Crustal deformation used to estimate earthquake recurrence in Apennines

Seismic hazard assessments require knowledge of the amount of strain accumulated and released along faults. This information can be obtained through measures of crustal deformation and from estimates of strain released by past earthquakes. Over time, the strain released by earthquakes should mirror the tectonic deformation.
Dose-response relationships of retinol in production of the Arnold-Chiari malformation.

A single oral dose of 5000, 10 000, 15 000, 20 000 or 30 000 I.U. vitamin A alcohol (retinol) on the eighth day of gestation in the pregnant hamster resulted in the production of the Arnold-Chiari malformation types I and II in 0, 6.6, 57, 56 and 85%, respectively, of all fetuses examined. The pattern and severity of the malformations of the chondrocranium and viscerocranium changed as the dose of retinol was increased. The smallest dose of retinol used in the present study which induced gross terata in hamsters was approximately 11 times greater than the highest oral daily dose of retinol used in clinical cancer chemoprevention trials.
A radix-4 on-line division design and its application to networks of on-line modules

On-line division is one of the slowest operations among the basic arithmetic operations and naturally becomes a bottleneck in networks of on-line modules that use it. A higher radix divider has a good potential to attain higher throughput than radix-2 dividers and therefore improve the overall throughput of networks where division is needed. The improvement in throughput when using radix 4 is not straightforward since several components of the divider become more complex than in the radix-2 case. Previously proposed radix-4 designs were based on operand pre-scaling to simplify the selection function and reduce the critical path delay, at the cost of more complexity in the algorithm conditions and operations, plus a variable on-line delay, which is a very unattractive feature when small precision values are used (usually the case for DSP). These designs include several phases for pre-scaling and actual division. This paper proposes a design approach based on overlapped replication that results in a radix-4 on-line division module with low algorithm complexity, single division phase, less restrictions to the input values, and a small and fixed on-line delay.
Nonfouling Behavior of Polycarboxybetaine-Grafted Surfaces: Structural and Environmental Effects

Zwitterionic carboxybetaine (CB) has unique dual functionality for ligand immobilization on a nonfouling background. The properties of CB groups depend on their spacer groups between the positive quaternary amine groups and the negative carboxyl groups and environmental factors (e.g., ionic strengths and pH values). In this work, five polycarboxybetaines were prepared, including one polycarboxybetaine methacrylate (polyCBMA) and four polycarboxybetaine acrylamides (polyCBAAs) with different spacer groups. The polymers were grafted from a gold surface covered with initiators using surface-initiated atom transfer radical polymerization. Fibrinogen adsorption was measured as a function of ionic strengths and pH values using surface plasmon resonance sensors. The responsive protein adsorption on four polyCBAAs was mapped out. Results show that most of these surfaces exhibit high protein resistance in a wide range of ionic strengths and are more effective than zwitterionic self-assembled monolayers. Although protein adsorption tends to increase at low ionic strength and low pH value, it is still very low for polycarboxybetaines with a methylene, an ethylene, or a propylene spacer group but is more evident for polyCBAA with a longer spacer group (i.e., a pentene group). The response to ionic strengths and pH values can be attributed to the antipolyelectrolyte and protonation/deprotonation properties of polycarboxybetaines, respectively. Both of these properties are related to the spacer groups of CBs.
Specific Disruption of Hippocampal Mossy Fiber Synapses in a Mouse Model of Familial Alzheimer's Disease

The earliest stages of Alzheimer's disease (AD) are characterized by deficits in memory and cognition indicating hippocampal pathology. While it is now recognized that synapse dysfunction precedes the hallmark pathological findings of AD, it is unclear if specific hippocampal synapses are particularly vulnerable. Since the mossy fiber (MF) synapse between dentate gyrus (DG) and CA3 regions underlies critical functions disrupted in AD, we utilized serial block-face electron microscopy (SBEM) to analyze MF microcircuitry in a mouse model of familial Alzheimer's disease (FAD). FAD mutant MF terminal complexes were severely disrupted compared to control - they were smaller, contacted fewer postsynaptic spines and had greater numbers of presynaptic filopodial processes. Multi-headed CA3 dendritic spines in the FAD mutant condition were reduced in complexity and had significantly smaller sites of synaptic contact. Significantly, there was no change in the volume of classical dendritic spines at neighboring inputs to CA3 neurons suggesting input-specific defects in the early course of AD related pathology. These data indicate a specific vulnerability of the DG-CA3 network in AD pathogenesis and demonstrate the utility of SBEM to assess circuit specific alterations in mouse models of human disease.