cssi/SciSciGPT-SciSciNet huggingface dataset:
Oncological Outcomes of Patients with Locally Advanced Rectal Cancer and Lateral Pelvic Lymph Node Involvement.

Introduction The optimal management of patients with radiologically positive lateral pelvic lymph nodes in locally advanced rectal cancer remains unclear. We compared local recurrence rates and oncological outcomes of patients with locally advanced cancer with and without lateral pelvic lymph nodes. Methods Patients who underwent curative surgery for stage III rectal adenocarcinoma between 2009 and 2014 and had a preoperative MRI at our institution as well as preoperative neoadjuvant treatment were included. Patients with positive lateral pelvic lymph nodes (iliac or obturator nodes) on preoperative MRI (LPND +) were compared to patients with no lateral pelvic nodal disease (LPND -). Data were collected from a prospectively maintained institutional database. Differences between the groups were compared in univariate analysis. Log-rank test was used to evaluate overall and disease-free survival between the groups. Results A total of 125 patients met inclusion criteria with a mean age of 56.3 ± 12.2 and 75% were male. Median follow-up was 44 months (IQR 32, 106). Positive LPND was present on preoperative MRI in 43/125 (34.4%) patients who were in the LPND (+) group. Seventeen out of 43 patients had a post-neoadjuvant treatment MRI and 15 patients had a decrease in size of nodes or disappearance of LPND. On univariate analysis, LPND (+) and LPND (-) groups were comparable. Local recurrence rates were higher in the LPND (+) group, although this was not statistically significant (16.3% vs. 6%, p = 0.06). Overall and disease-free survival rates were comparable between the LPND (+) and LPND (-) groups (p = 0.97, p = 0.51). Conclusions Management of patients with advanced rectal cancer and radiologically positive lateral pelvic lymph nodes is challenging due to high local recurrence rates. Further studies are needed to develop care pathways for the optimal treatment processes.
New Test, Old Disease: A Case Series of Diabetic Ketoalkalosis.

Abstract Background Diabetic ketoalkalosis (DKAlk) was first described in 1967 as a rare complication of diabetic ketoacidosis with normal or elevated pH/bicarbonate and elevated anion gap (AG) from high β-hydroxybutyrate (BHB). Objective We report a case series of patients with DKAlk to show how venous blood gas (VBG) electrolytes alone may misdiagnose these patients. Methods This was a case series of DKAlk patients with concomitant VBG and basic metabolic panel (BMP) electrolytes who met the following criteria for DKAlk: BMP hyperglycemia (glucose >250 mg/dL), elevated AG (>15 mEq/L), elevated BHB (>1.2 mmol/L), and high Delta (Δ) gap (>6 mEq/L [bicarbonate gap (BG): measured bicarbonate – 24] – [AG – 12]). Data are reported as median with interquartile range (IQR) (25%, 75%) and group comparisons utilized Mann-Whitney U test (two-tailed, α = 0.05). Results We found 10 patients with DKAlk in 2 months. Patients ranged in age from 13 to 77 years, 50% were male, and all were African American. Most patients (8 of 10) were vomiting with hyperglycemia (350 to >600 mg/dL). DKAlk BMP AG ranged from 18 to 34 mmol/L and BHB from 1.74 to 9.09 mmol/L. For bicarbonate, we found no significant difference between VBG (24 mmol/L) and BMP (22 mmol/L) (p = 0.796). VBG chloride (98 mmol/L) was significantly higher than BMP chloride (88 mmol/L) (p Conclusions We found that DKAlk is more common than previously reported. We recommend screening with BMP electrolytes and BHB levels for hyperglycemic ED patients who are vomiting or suspected of hypovolemia.
Comparative and functional morphology of chevron bones among mammals

Tail morphology and function vary considerably across mammals. While studies of the mammalian tail have paid increasing attention to the caudal vertebrae, the chevron bones, ventrally positioned elements that articulate with the caudal vertebrae of most species and that serve to protect blood vessels and provide attachment sites for tail flexor musculature, have largely been ignored. Here, morphological variation in chevron bones is documented systematically among mammals possessing different tail locomotor functions, including prehensility, terrestrial propulsion (use for pentapedal locomotion), and postural prop, during which chevron bones are presumably under different mechanical stresses or serve different mechanical roles. Several chevron bone morphotypes were identified along the tail, varying both within and between tail regions. While some morphotypes were present across many or all clades surveyed, other morphotypes were clade-specific. Chevron bone dorsoventral height was examined at key vertebral levels among closely related species with different tail locomotor functions to assess whether variation followed any functional patterns. Dorsoventral height of chevron bones differed between prehensile- and nonprehensile-tailed, prop-tailed and nonprop-tailed, and pentapedal and nonpentapedal mammals. However, small sample sizes precluded rigorous statistical analyses. Distinctions were also qualified among species (not grouped by tail locomotor function), and the utility of metrics for quantifying specific aspects of chevron bone anatomy is discussed. This study offers information about the functional morphology of mammalian tails and has implications for reconstructing tail function in the fossil record.
32-Element Array Receiver for 2-D Spatio-Temporal Δ-Σ Noise-Shaping

The concept of two-dimensional (2-D) space-time Δ-Σ noise-shaping for radio frequency (RF) array processing systems has been proposed in earlier work. This approach can provide supralinear improvements in the overall noise figure (NF), linearity, and resolution of an N-port receiver at the cost of a linear increase in the number of elements. This paper describes a proof-of-concept 32-element array receiver that is suitable for driving first-order spatio-temporal Δ-Σ noise-shaping analog-to-digital converters (ADCs). The design has been realized using board-level components. It operates at a center frequency of 2.6 GHz and uses an on-board dense sleeve monopole antenna array with a spatial oversampling factor of 4. Calibration is achieved to decrease the mismatch between channels, resulting in gain mismatch reduction by a factor of 1.8 and phase mismatch reduction by a factor of 2.9. Over-the-air measurement results prove the functionality of the proposed array receiver.
Effect of Comorbid Depression on Surgical Outcomes After Craniotomy for Malignant Brain Tumors: A Nationwide Readmission Database Analysis.

Objective Quality of life is paramount in patients with advanced cancer and may be adversely affected by comorbid depression. We hypothesized that comorbid depression is associated with higher rates of postoperative complications, worse functional outcomes, and higher rates of readmission after craniotomy for resection of malignant intracranial tumors. Methods The National Readmissions Database was queried from 2010 to 2014 to identify adult patients undergoing craniotomy for malignant brain tumor resection. The primary psychiatric disease assessed was major depressive disorder (MDD). Outcomes evaluated included neurologic or other major complications, incidence of nonroutine discharge, and unplanned readmission at 30 and 90 days. Results Of the 57,621 craniotomies for malignant neoplasms included in the analysis, 11.32% of patients had clinically diagnosed MDD. The presence of MDD was associated with nonroutine discharge (odds ratio, 1.10–125; P 7 days experienced higher rates of 30-day and 90-day readmissions. Conclusions There is a clinically significant rate of comorbid MDD in patients with malignant intracranial tumors, and MDD is associated with worse perioperative outcomes. Given the wealth of behavioral and pharmaceutical therapies available, MDD is a modifiable risk factor in this cohort that clinicians should be vigilant in screening for and initiating appropriate treatment protocols.
Venous Waveform Analysis Correlates With Echocardiography in Detecting Hypovolemia in a Rat Hemorrhage Model.

BackgroundAssessing intravascular hypovolemia due to hemorrhage remains a clinical challenge. Central venous pressure (CVP) remains a commonly used monitor in surgical and intensive care settings f...
Imaging the Formation of High-Energy Dispersion Anomalies in the Actinide UCoGa 5

Combined state-of-the-art experimental and theoretical investigations of a strongly correlated electronic material point to spin fluctuations as the prime mechanism for ``dressing'' electrons.
Pseudomonas putida MPE, a manganese-dependent endonuclease of the binuclear metallophosphoesterase superfamily, incises single-strand DNA in two orientations to yield a mixture of 3'-PO4 and 3'-OH termini.

Pseudomonas putida MPE exemplifies a novel clade of manganese-dependent single-strand DNA endonuclease within the binuclear metallophosphoesterase superfamily. MPE is encoded within a widely conserved DNA repair operon. Via structure-guided mutagenesis, we identify His113 and His81 as essential for DNA nuclease activity, albeit inessential for hydrolysis of bis-p-nitrophenylphosphate. We propose that His113 contacts the scissile phosphodiester and serves as a general acid catalyst to expel the OH leaving group of the product strand. We find that MPE cleaves the 3' and 5' single-strands of tailed duplex DNAs and that MPE can sense and incise duplexes at sites of short mismatch bulges and opposite a nick. We show that MPE is an ambidextrous phosphodiesterase capable of hydrolyzing the ssDNA backbone in either orientation to generate a mixture of 3'-OH and 3'-PO4 cleavage products. The directionality of phosphodiester hydrolysis is dictated by the orientation of the water nucleophile vis-a-vis the OH leaving group, which must be near apical for the reaction to proceed. We propose that the MPE active site and metal-bound water nucleophile are invariant and the enzyme can bind the ssDNA productively in opposite orientations.
Good prophets know when the end is near

We consider a class of online decision-making problems with exchangeable actions, where in each period a controller is presented an input type drawn from some stochastic arrival process and must choose an action, and the final objective depends only on the aggregate type-action counts. Such a framework encapsulates many online stochastic variants of common optimization problems with knapsack, bin packing and generalized assignment as canonical examples. In such settings, we study a natural model-predictive control algorithm that, in each period, acts greedily based on an updated certainty-equivalent optimization problem. We introduce a simple, yet general, condition under which this algorithm obtains uniform additive loss (independent of the horizon) compared to an optimal solution with full knowledge of arrivals. Our condition builds on the compensated coupling technique of Vera and Banerjee (2019), providing a unified view of how uniform additive loss arises as a consequence of the geometry of the underlying decision-making problem. Our characterization allows us to derive uniform-loss algorithms for several new settings, including the first such algorithm for online stochastic bin-packing. It also lets us study the effect of other modeling assumptions, including choice of horizon, batched decisions, and limited computation. In particular, we show that our condition is fulfilled by the above-mentioned problems when the end of the time-horizon is known sufficiently long before the end. In contrast, if at a late stage, there is still uncertainty about the end of the time horizon we show that such uniform loss guarantees are impossible to achieve. We demonstrate the performance of our algorithm via large-scale experiments on real and synthetic data.
Micrometer-sized electrically programmable shape-memory actuators for low-power microrobotics.

Shape-memory actuators allow machines ranging from robots to medical implants to hold their form without continuous power, a feature especially advantageous for situations where these devices are untethered and power is limited. Although previous work has demonstrated shape-memory actuators using polymers, alloys, and ceramics, the need for micrometer-scale electro–shape-memory actuators remains largely unmet, especially ones that can be driven by standard electronics (~1 volt). Here, we report on a new class of fast, high-curvature, low-voltage, reconfigurable, micrometer-scale shape-memory actuators. They function by the electrochemical oxidation/reduction of a platinum surface, creating a strain in the oxidized layer that causes bending. They bend to the smallest radius of curvature of any electrically controlled microactuator (~500 nanometers), are fast (
Change-Event Steals “Athlete” from “College Athlete”: Perceived Impact and Depression, Anxiety, and Stress

Introduction This research sought to establish the impact of the change-event of COVID-19 on college athletes and members of other campus groups (eg, marching band, eSports, Reserve Officers Training Corps). The specific purpose was to assess the perceived impact and impact on mental health (eg, depression, anxiety, and stress). Methods The survey battery presented a total of 37 items. Demographic, sport or group-specific, and academic-related questions were included alongside the assessment of psychological well-being coming from the Depression Anxiety Stress Scale-21. Results There were 249 participants completing some or all of the survey battery. It is notable that 172 participants (69.1%) indicated "a lot has changed". Common one-word responses to the experience surrounding this change-event were feeling disappointment, upset, frustrated, sadness, annoyance, and depression. Life events that conjured similar magnitude of emotion included significant injury, surgery, and losing a loved one. There were no differences by sport for the depression subscale, but 110 participants reported elevated scores and females had a higher mean depression subscale score compared with males. Differences between sports for the anxiety subscale were negated when evaluating Bonferroni correction for multiple tests, but 69 participants reported elevated scores and females had a higher mean anxiety subscale score compared with males. There was no difference by sport for the stress subscale, but 77 participants reported elevated scores and females had a higher mean stress subscale score compared with males. Discussion Authors urge the campus and athletics community to be diligent in monitoring the holistic wellness of college athletes and members of other campus groups. Mainly, we contend it is important to consider that COVID-19 is a significant and widespread change-event, and other change-events are known to have significant impact. We should consider that COVID-19 may be acutely and longitudinally impactful to the American college student.
Calculation of MTDSC Signals, Factors Effecting the Signals and Applications in Drug Development: A Recent Study

The author focuses on the basic principle of Modulated Temperature Differential Scanning Calorimetry (MTDSC), the advantages of MTDSC over conventional DSC, the calculation of heat flow and heat capacity components, factors affecting MTDSC signals, and MTDSC application in drug development in this paper. In MTDSC, a sinusoidal modulation is layered on top of a traditional linear heating ramp, in which the sample temperature rises steadily over time. The linear heating rate provides the same information as a regular DSC, however the sinusoidal heating rate determines the fraction of total heat flow that corresponds to the changing heat rate. The overall heat flow rate is determined by heat capacity and heat capacity change. Reversing heat flow, also known as the heat capacity component of total heat flow, is a portion of heat flow.The kinetic component is time dependent and is also known as non-reversing heat flow since it does not adapt to changes in the heating rate. Optimized experimental settings must be chosen for accurate measurements of heat flow and heat capacity components. MTDSC is used in preformulation studies to identify Tg, polymorphic forms, and polymorphic transitions, as well as to ensure stability through drug excipient compatibility tests and to calculate the enthalpy of polymorphic transitions.
An Exploration of Perceptions of Justice in a Career-Forward Undergraduate Chemistry Laboratory Course

Persistence in academic and career settings is a major issue for students enrolled in science and engineering programs, particularly those who identify as female or as members of certain underrepresented ethnic minorities (URM). This exploratory study determined the degree to which organizational justice has explanatory power in complimenting the Mediation Model of Research Experiences (MMRE) in a career-forward laboratory curriculum context. A career-forward approach to curriculum targets persistence by basing the student experience on the content, context, and practices of the targeted career field in developmentally appropriate ways. Participants were 157 undergraduate students taking General Chemistry Laboratory for Engineering Majors. Confirmatory factor analysis of survey responses indicated an acceptable fit for the established four-factor model of organizational justice (χ2(164, n = 157) = 378.447, p = 0.000, IFI = 0.935, CFI = 0.934, NFI = 0.891 RMSEA = 0.092). Bivariate correlations among variables from the two frameworks show that the experience of URM students is different than that of their non-URM peers. Notably, identity as an engineer was more strongly correlated to aspects of organizational justice, and justice played a role in students’ views on teamwork. This supports a prior hypothesis that the negative relationship between teamwork self-efficacy and commitment to an engineering career for URM participants may be related to issues of marginalization within their groups. Evaluation of a combined MMRE organizational justice model with future studies is merited, especially for contexts involving the use of teamwork and/or student collaboration.
Accuracy of self- and proxy-rated hearing among older adults with and without cognitive impairment.

BACKGROUND Hearing loss is highly prevalent among older adults with cognitive impairment and may exacerbate neuropsychiatric symptoms and affect interactions with others. Although audiometry is the gold standard for measuring hearing, it is not always used in research or clinical settings focused on the care of individuals with cognitive impairment. Subjective assessments of hearing, both self- and proxy-rated, are widespread but may not adequately capture the presence of hearing loss as compared to audiometry. This study investigates the concordance between subjective and objective hearing assessments among older adults with and without cognitive impairment and evaluates factors associated with concordance. METHODS Participants were a subset of the Atherosclerosis Risk in Communities Neurocognitive Study (ARIC-NCS), a prospective cohort study representing four US communities with adjudicated cognitive diagnoses and audiometric data, totaling 3326 self-rated and 520 proxy-rated hearing assessments. Sensitivity and specificity were calculated, and multivariable logistic regression estimated the magnitude of the association between the concordance of hearing assessments and variables of interest. RESULTS Sensitivity and specificity for self-rated hearing status were 71.2% and 85.9% among cognitively normal older adults, 61.1% and 84.9% among persons with MCI, and 52.6% and 81.2% among persons with dementia, respectively. For proxy-rated hearing, sensitivity and specificity were 65.7% and 83.3% for persons with MCI and 73.3% and 60.3% for persons with dementia, respectively. Female sex was positively associated with concordance for self-rated hearing assessments. CONCLUSIONS The low sensitivity of self- and proxy-rated hearing assessments compared to audiometry suggests that hearing loss among older adults with cognitive impairment may go underreported and unaddressed in subjective assessments. Clinicians and researchers should recognize the limitations of using self- and proxy-rated hearing assessments as measures of hearing status and incorporate objective audiometric evaluation whenever possible.
Synthesis and biodistribution of F-18 labeled scyllo-inositol derivatives as potential probes for detecting amyloid beta oligomers

1935 Objectives Scyllo-inositol appears to bind small Aβ oligomers inhibiting their aggregation and deposition as amyloid plaque in the brain. Mechanistic data indicate scyllo-inositol binds and neutralizes these oligomers into soluble complexes while reducing the amount of larger oligomeric species. An F-18 labeled scyllo-inositol derivative may be beneficial as a probe for studying the early formation of amyloid plaque. Here we present two such labeled derivatives and their biodistributions. Methods 1-Deoxy-1-[18F]fluoro-2,3,4,5,6-penta-O-acetyl-scyllo-inositol (1) and 1-deoxy-1-[18F]fluoro-scyllo-inositol (2) were prepared from the benzyl myo-mesylate using K18F/Kryptofix in acetonitrile at 150oC. The crude product was treated with HBr/acetic acid at 250C and after purification furnished the labeled acetylated scyllo-inositol derivative 1. Mild base hydrolysis followed by C18 SepPak purification gave the unprotected labeled compound 2. Biodistributions were performed in normal mice. Results Radiofluorination yields were 20% and 10% for F-18-scyllo-inositols 1 and 2, respectively. Brain uptake (%DPG) at 5, 30 and 60min for the acetylated derivative 1 was 0.8%, 0.9% and 0.26%. Brain uptake for derivative 2 was 0.18%, 0.30% and 0.36%, with the majority of the activity accumulating in kidneys. Conclusions The acetylated F-18-scyllo-inositol 1 exhibited 3 times higher brain accumulation within 30 min than that of F-18-scyllo-inositol 2. Compound 1 also showed significant brain clearance in normal rats at 60 min. These results suggest binding studies to soluble oligomers and to Alzheimer9s brain tissue for this compound are warranted.
Multinomial prediction intervals for micro-scale highway emissions

Legislation passed in the early 1990’s requires that the air quality impacts of individual transportation projects be evaluated. Most of the current modeling practices to predict these air quality impacts use regionally-based average pollutant emissions rates without acknowledging that local traffic conditions and vehicle fleet compositions can vary widely. Yet it is known that some of the major health problems resulting from pollutants are immediate and localized, such as asthmatic reactions. There is a need for prediction methods that utilize small time-period variability in traffic volumes, combined with localized measures of emissions rates, to predict localized pollutant levels. Technology has been developed for measuring micro-scale levels of certain pollutants, but the simultaneous collection of micro-scale (e.g. 5-minute) traffic counts is expensive and impractical. In contrast, automated hourly count volumes are ubiquitous and available for most roadways. In this paper, we present a method for constructing prediction intervals for localized pollutant levels when only the total traffic volume count is known. The method utilizes micro-scale traffic volume counts and emissions factors previously collected on comparable roadways. To demonstrate how the prediction methods can be applied, we utilize micro-scale emissions data collected as part of a University of California, Davis experiment to predict carbon monoxide (CO) concentrations during worst-case meteorological conditions.
Drinks like a fish: Using zebrafish to understand alcoholic liver disease

Steatosis is the most common consequence of acute alcohol abuse, such as occurs during a drinking binge. Acute alcohol induced steatosis may predispose to more severe hepatic disease. We have developed a model of alcoholic liver disease (ALD) in zebrafish larvae to provide a system in which the genes and pathways that contribute to steatosis can be rapidly identified. Zebrafish larvae represent an attractive vertebrate model for studying acute ALD because they possess the pathways to metabolize alcohol, the liver is mature by 4 days post-fertilization (dpf), and alcohol can be simply added to their water. Exposing 4 dpf zebrafish larvae to 2% ethanol (EtOH) for 32 hours achieves ∼80 mM intracellular EtOH and upregulation of hepatic cyp2e1, sod, and bip, indicating that EtOH is metabolized and provokes oxidative stress. EtOH-treated larvae develop ALD as demonstrated by hepatomegaly and steatosis. Increased lipogenesis driven by the sterol response element binding protein (SREBP) transcription factors is essential for steatosis associated with chronic alcohol ingestion but it has not been determined if the same pathway is essential for steatosis following a drinking binge. We report that several Srebp target genes are induced in the liver of zebrafish exposed to EtOH. We used fish which harbor a mutation in the gene encoding the membrane bound transcription factor protease 1 (mbtps1; also called site-1 protease) and embryos in which the Srebp cleavage activating protein (scap) is knocked down to determine the requirement of this pathway in acute ALD. We find that both means of blocking Srebp activation prevents steatosis in response to 2% EtOH. Moreover, this is accompanied by the failure to activate several Srebp target genes in response to alcohol. We conclude that Srebps are required for steatosis in response to acute alcohol exposure. Moreover, these data highlight the utility of zebrafish as a useful new vertebrate model to study ALD.
Pulsed amperometric detection of sulfur compounds: Part II. Dependence of response on adsorption time

Abstract A mathematical model is developed for the response of PAD and is applied to data from the study of Ip as a function of tads for evaluation of the adsorption rate constants, and the maximum molar surface coverage for thiourea at a Pt electrode. The results are, respectively: k1 = 4.1 × 104 M−1 s−1, k−1 = 1.9 s−1, and Γ0 = 1.3 × 10−10 mol cm−2. The calculated adsorption equilibrium constant (k1/k−1) is 2.1 × 104 M−1, compared to 4.9 × 104 M−1 calculated from the plot of 1/Ip vs. 1/cb for cb > 1.0 × 10−4 M and tads = 8500 ms. Analytical calibration procedures are examined; linear plots of 1/Ip vs 1/cb cannot be expected for cases of mixed transport-isotherm control of detector response.
Opioid Analgesia: Managing Risks and Obtaining Benefits

Opioid analgesia is critical to the management of acute pain. For the many millions who suffer from chronic pain diseases and chronically painful conditions, opioid analgesia may improve their longitudinal well-being and quality of life. However, their access to successful opioid analgesia will hinge on the training, skills, and experience of their physicians. Understandably, many physicians feel uncomfortable prescribing opioids for long-term use without specific training in the evaluation and management of chronic pain and the risks associated with opioid analgesia particularly addiction [1,2]. The well-documented negative impact of chronic pain on health outcomes and the public health cost of inadequate treatment …
SAR and chemistry of Aurora kinase inhibitors: Discovery of PF-3814735, an oral clinical candidate

LB-147 Over expression and amplification of Aurora-2, a key regulator of mitosis plays important but distinct roles in the G2 and M phases of the cell cycle and has been reported in different tumor types including breast, colon, pancreatic, ovarian and gastric cancer. We report herein the discovery and preclinical profile of PF-3814735, a novel heretofore unreported pyrimidine scaffold based ATP-competitive, reversible inhibitor of Aurora-1 and 2 kinases. SAR at the C2 and C4 positions of the pyrimidine scaffold led to a series with great in vitro potency. Subsets of analogs from this series that demonstratedexcellent in vitro ADME profile were selected for further in vivo pharmacological and ADME profiling. These efforts led to the discovery of PF-3814735, which inhibits Aurora-1 kinase with an IC50 value of 0.8 nM and Aurora-2 kinase with an IC50 value of 5 nM and has corresponding potent cellular and biochemical activity. Oral administration of PF-3814735 demonstrated in vivo pharmacology and high oral bioavailability (%F>50). Treatment with PF-3814735 resulted in significant tumor growth inhibition at tolerable doses in multiple tumor xenograft models. In summary, we will be describing the chemistry and SAR that led to the discovery of a potent Aurora kinase inhibitor, PF-3814735 that is the clinical candidate and is currently in Phase I trials. Design,synthesis, inhibitor kinase and cell activity, kinase selectivityprofile, ADME as well as inhibitor chemical structure will be presented.
Novel biomarkers of periodontitis and/or obesity in saliva-An exploratory analysis.

Objective Recent studies point to the clinical and research utility of saliva as a valuable diagnostic aid for monitoring periodontal health. The objectives of this study were to detect novel biomarkers attributed to chronic inflammation in saliva and to determine if the levels of these markers correlate with severity of periodontitis and with standard obesity measures in participants in a periodontal maintenance program.
Compensating Variation as a Measure of Welfare Change

The concept of “compensating variation” introduced by Hicks (1939), and developed by Henderson (1941) and Hicks (1942, 1956), remains along with its sister concept of “consumer’s surplus” the principal tool of analysis underlying present-day “cost- benefit analysis” and “applied welfare economics” (cf. Mishan, 1971; Harberger, 1964, 1971). In two previous papers (Chipman & Moore, 1976, 1980) we have respectively analyzed the consumer’s surplus and the compensating and equivalent variations in the context of single-valued, differentiable demand functions. In the present paper we extend the analysis of the latter two concepts to the context of demand correspondences. Since the alternative specifications of homothetic and parallel1 prefences turn out to be of particular importance in providing a rigorous justification for certain uses of the compensating variation as a welfare measure, we include a detailed development of the principal properties of demand correspondences and indirect preferences under these two specifications-particularly that of “parallel” preferences in Appendix B. Our main results (Theorems 1 and 3) establishing necessary conditions for the extended applicability of the compensating variation both make use of a basic duality theorem concerning the relationship between indirect preferences and demand correspondences proved in Appendix A (Theorem 6).
A comparison of a limiter-discriminator, delay and coherent detection for pi /4 QPSK

A brief description is given of limiter-discriminator, delay, and coherent detection of pi /4 quadrature phase shift keying (QPSK). Simulated bit error rate (BER) performance of these detectors in static and Rayleigh faded fields is presented. Performance in delay spread faded fields is also given. Results of the use of an equalizer with the coherent detector in delay spread faded fields is evaluated. Three methods of detecting pi /4 QPSK are evaluated. A brief description of the operation and an estimate of implementation complexity is given for each detector. Simulated results of BER performance for each detector in static, Rayleigh, and delays spread faded fields are then presented. The use of an adaptive decision feedback equalizer with a coherent detector is then evaluated for use in delay spread faded fields. >
Ethics laws and the outside earnings of politicians: The case of Alabama's “legislator-educators”

This paper has reported evidence on the returns to legislating. In particular, we examined the distributional impact of a provision of Alabama's Code of Ethics which allows sitting state legislators to be on the payroll of public institutions of higher education. Using salary and educational budget data for 1987–88, we found that public funding per student for the junior and senior colleges in the state which employ legislators as educators is significantly higher than that received by comparable institutions.
Inspection of the Engineered FhuA ΔC/Δ4L Protein Nanopore by Polymer Exclusion

Extensive engineering of protein nanopores for biotechnological applications using native scaffolds requires further inspection of their internal geometry and size. Recently, we redesigned ferric hydroxamate uptake component A (FhuA), a 22-β-stranded protein containing an N-terminal 160-residue cork domain (C). The cork domain and four large extracellular loops (4L) were deleted to obtain an unusually stiff engineered FhuA ΔC/Δ4L nanopore. We employed water-soluble poly(ethylene glycols) and dextran polymers to examine the interior of FhuA ΔC/Δ4L. When this nanopore was reconstituted into a synthetic planar lipid bilayer, addition of poly(ethylene glycols) produced modifications in the single-channel conductance, allowing for the evaluation of the nanopore diameter. Here, we report that FhuA ΔC/Δ4L features an approximate conical internal geometry with the cis entrance smaller than the trans entrance, in accord with the asymmetric nature of the crystal structure of the wild-type FhuA protein. Further experiments with impermeable dextran polymers indicated an average internal diameter of ∼2.4 nm, a conclusion we arrived at based upon the polymer-induced alteration of the access resistance contribution to the nanopore’s total resistance. Molecular insights inferred from this work represent a platform for future protein engineering of FhuA that will be employed for specific tasks in biotechnological applications.
Assessing the Impact of Testing Aids on Post-Secondary Student Performance: A Meta-Analytic Investigation

Testing aids, including student-prepared testing aids (a.k.a., cheat sheets or crib notes) and open-textbook exams, are common practice in post-secondary assessment. There is a considerable amount of published research that discusses and investigates the impact of these testing aids. However, the findings of this research are contradictory and inconclusive. The current meta-analytic investigation provides a general measure of the impact of both student-prepared testing aids and the use of open-textbook exams on student exam performance in post-secondary education, while examining variables that may moderate the effects of testing aids on student exam performance. The results indicate that, overall, testing aids can produce a moderate impact on student exam performance, with student-prepared testing aids associated with a larger effect (d=.402) relative to open-textbook exams (d = 0.257). The results are discussed in terms of their implications for college course instructors and for informing the broader debate about the role of testing aids in long-term student learning and mastery of course material.
The determination of item difficulty when chance success is a factor

The evaluation of the level of difficulty of a test item is ordinarily derived from the proportion of a specified population passing or failing the item. With items that have a limited number of alternative responses there must be a correction in this proportion to make allowance for chance success. A table of corrected proportions is given for different numbers of alternatives varying from two to eight.
A Model for Introducing Student Teachers to Collaboration.

Abstract There has been a great deal of recent discussion in schools about the need for teachers to implement programs through collaboration. In order for teachers to work together effectively, they need to become comfortable with the collaborative process. Student teachers need to be exposed to experiences where they have the opportunity to collaborate with colleagues. This paper describes and analyzes a model in which student teachers are placed in a collaborative situation at a participating elementary school Data sources include student teacher journals, student teacher questionnaires, interviews with cooperating teachers, and supervisor field notes. Advantages and disadvantages; cooperating teacher and supervisor roles; and the effects of collaborative work on student teachers' performance in relation to planning and lesson execution, professional behavior, and self‐esteem are explored. The results indicate that, despite a few disadvantages, there are many benefits to introducing collaboration during...
Digital Logic and Arithmetic: Background for Interfacing Microcomputers

Abstract In order to effectively plan and develop projects involving microcomputers, the industrial engineer requires background information on number systems, binary arithmetic, and binary logic. In this tutorial article, a basic introduction to these topics is provided. Specific topics include: positional number systems, conversion between number systems, addition and subtraction of binary numbers, the two's complement of negative numbers, the ASCII and Gray codes, the basic logic functions (AND, OR, NOT, NAND, NOR, XOR), and some applications of basic logic functions, including a decoder, an adder, and a binary latch. This is the first of an integrated series of articles dealing with concepts and techniques for interfacing microcomputers to industrial devices.
POLARIZATION OF COSMIC-RAY $mu$ MESONS: THEORY

The expected polarization of cosmic-ray $\ensuremath{\mu}$ mesons is calculated on the basis of the two-component theory of the neutrino. The polarization is found to reveal the energy spectrum of $\ensuremath{\pi}$ mesons which decay into $\ensuremath{\mu}$-mesons at high altitudes, provided that the depolarization on penetration through the atmosphere is known. The depolarization caused by the Coulomb scattering is estimated to be several percent and practically independent of the energy of $\ensuremath{\mu}$ mesons at production. The depolarization in the absorber is found to be negligible.
Development of syntax in a retarded girl using procedures of imitation, reinforcement, and modelling.

Three experiments demonstrated the development and generalized use of a singular and plural declarative sentence in a child initially lacking sentence form responses. In each experiment, an adult(s) served as a language model(s), and consequences (sweets) were provided for imitation of the model. During training trials, an item(s) was displayed first to the model(s) then to the subject; these displays were accompanied by requests to label the item(s). Generalization was assessed by a number of probe trials that were periodically interspersed among training trials. During these trials, the subject was requested to label the displayed item(s) without any preceding labelling response from the model. Using these procedures, generalized use of a singular sentence (“That is one ———”) resulted in Experiment I, and generalized use of a plural sentence (“These are two ———”) resulted in Experiment II. In Experiment III, two models (a singular and a plural sentence model) were made available to the subject but imitation of only one model was reinforced during any one condition. Results indicated the subject labelled probe (generalization) items with the same sentence form that was modelled and reinforced during training trials.
Surface alloy formation studied by scanning tunneling microscopy: Cu(100) + Au−c(2 × 2)

Abstract The ordered surface alloy formed by Au deposited on Cu(100) at room temperature is studied using scanning tunneling microscopy (STM). The formation of a CuAu alloy monolayer is demonstrated by STM images showing c(2 × 2) ordering with two unequal peaks per unit cell. Longer-range images show linear features in which misfit strain is apparently relieved by transverse atomic displacements. The surface topography of islands shows that they also consist of a CuAu alloy layer, which demonstrates that alloy formation arises by Au replacement of Cu atoms in the surface.
Stimulus memory in concept attainment

Both inconsistencies in concept guesses and attribute-recall errors were affected by the type of stimulus series (positive, negative, mixed) and by stimulus position in the series. Selected aspects of recall were related to concept guesses.
Synthesis of heterogeneous nuclear RNA in full-grown oocytes of xenopus laevis (Daudin)

Abstract At various times following injection of either 3 H-GTP or 32 PO 4 into full-grown (stage 6) Xenopus laevis oocytes, RNA has been extracted and fractionated on polyacrylamide gels. Based on size, base composition and incorporation data, we have defined the kinetics of synthesis and accumulation of ribosomal RNA (40S, 28S, 18S), heterogeneous RNA of high molecular weight (>40S) and heterogeneous RNA migrating with molecular weights of from 4S to 40S. Nuclear isolations have been performed to determine the cellular distribution of these classes of RNA as a function of time. Evidence is presented which shows that stage 6 oocytes synthesize RNA which by virtue of its size, base composition, rapid turnover and nuclear location is equivalent to the heterogeneous nuclear RNA observed in somatic cells. In addition, the data suggest synthesis of a class of nuclear RNA with a half-life of several hours. A small fraction (5%) of the nuclear RNA is stable, enters the cytoplasm and may represent RNA added to the stockpile of maternal transcripts known to be present in stage 6 oocytes.
Named and Namelessness: Alice Walker's Pattern of Surnames in The Color Purple

(2000). Named and Namelessness: Alice Walker's Pattern of Surnames in The Color Purple. ANQ: A Quarterly Journal of Short Articles, Notes and Reviews: Vol. 13, No. 1, pp. 38-41.
Formation of vesicovaginal fistulas in laparoscopic hysterectomy with electrosurgically induced cystotomy in female mongrel dogs.

Abstract Objective: The aim of this pilot study was to investigate the relationship between various types of laparoscopic bladder injuries and vesicovaginal fistula formation in an animal model. Study Design: Sixteen female mongrel dogs were divided into four groups. All animals underwent a laparoscopic hysterectomy. Those assigned to group 1 sustained a 1-cm bipolar cautery injury to the bladder base without perforation of the bladder mucosa. Animals in group 2 had two sutures of 2-0 polyglactin placed to incorporate the full thickness of the bladder wall and the vaginal cuff. The bladder injury to group 3 was a 1-cm bladder base laceration induced with monopolar cautery, repaired with two interrupted 2-0 polyglactin sutures. Group 4 underwent a bladder base cystotomy similar to those in group 3, with the closure incorporating the anterior vaginal wall. Animals were killed and necropsy was performed at least 28 days after surgery. The bladder and vagina of each animal were harvested en bloc. Evidence of a vesicovaginal fistula was determined by two methods: transurethral injection of indigo carmine solution under direct visualization and air injection during underwater submersion. Results: The four groups were comparable with regard to postoperative weight changes. No mongrels showed signs of infection or sepsis. Inspection of the harvested bladder and vagina revealed no fistulas in groups 1 and 2. One mongrel from group 3 and one from group 4 had evidence of a vesicovaginal fistula. With 95% CIs, the fistula rate would be at least 2% and as high as 38% if a larger study had been undertaken. Conclusion: The female mongrel is the first identified animal model of vesicovaginal fistula formation. In this setting, an electrosurgically induced cystotomy and repair of the bladder during the performance of a laparoscopic hysterectomy is associated with the formation of postoperative vesicovaginal fistulas. (Am J Obstet Gynecol 2002;187:1510-4.)
Secondary isotope effects in the mass spectra of C2D5OC2H5 and CD3CH2OC2H5

Secondary isotope effects were examined in the loss of methyl from the molecular ions of C 2 D 5 OC 2 H 5 and CD 3 CH 2 OC 2 H 5 for ion source processes and collisional activation (CA) processes. In the ion source loss of CH 3 was slightly favored over loss of CD 3 , but in CA the CH 3 loss was favored to a much larger extent than expected. A possible explanation is given which invokes an energy distribution function peaked near the appearance energy for the methyl loss process
Clinical practice guidelines in unstable angina improve clinical outcomes by assuring early intensive medical treatment.

Abstract OBJECTIVES To determine the influence of clinical practice guidelines on treatment patterns and clinical outcomes in unstable angina and the effectiveness of guideline reminders on implementing practice guidelines, two groups of medium and high risk patients with unstable angina were compared. BACKGROUND New guidelines have been published by the Agency for Health Care Policy and Research (AHCPR) for evaluating and managing patients with unstable angina. The impact of these guidelines to improve the quality of care has never been tested. METHODS Group 1 included 338 consecutive medium or high risk patients admitted before publication of the AHCPR guidelines, and group 2 consisted of 181 consecutive similar risk patients admitted after institution of the AHCPR guideline reminders at this institution. Dissemination of clinical practice guidelines was ensured by a grand rounds lecture and by posting guideline reminders on all group 2 patients’ charts within 24 h of admission. RESULTS The two groups were similar in terms of most baseline characteristics, including hypercholesterolemia, diabetes, hypertension, smoking history, baseline ST segment depression and previous coronary artery bypass graft surgery. Group 1 patients were older (68 ± 13 vs. 63 ± 16 years, p = 0.001) and more frequently had a previous myocardial infarction (39% vs. 22%, p = 0.001). Group 2 patients more frequently required intravenous nitroglycerin to control the index episode of chest pain (43% vs. 34%, p = 0.003). Group 2 patients more frequently received aspirin (96% vs. 88%, p = 0.009) during admission and underwent coronary angiography (71% vs. 58%, p = 0.006). More importantly, group 2 patients received oral beta-blockers (p = 0.008), aspirin and coronary angiography (p = 0.001) earlier than group 1 patients and experienced recurrent angina (29% vs. 54%) and myocardial infarction or death less frequently (3% vs. 9%, p = 0.028). CONCLUSIONS In unstable angina, clinical practice guidelines were associated with greater use of aspirin and coronary angiography and greater use and earlier administration of beta-blockers. Variation in drug use over time was also reduced. Objective improvement in clinical outcome was also noted. Thus, practice guidelines improve the quality of care of patients with unstable angina.
Factor structure of the Dementia Mood Assessment Scale in a cohort of community-dwelling elderly.

We examined the factor structure of the 28-item Dementia Mood Assessment Scale (DMAS), an instrument to assess depressive symptoms in older adults with cognitive impairment, in a cohort of 165 community-dwelling elderly with varying degrees of cognitive impairment. Factor analysis using principal components analysis and varimax rotation was performed to explore the presence of subscales and examine construct validity. A five-factor structure involving all 28 items accounting for 63.2% of the variance in the DMAS scores was derived. Factors were named: Depressed Affect, Environmental Interaction, Diurnal Patterns, Agitation/Suspicion, and Somatic Indicators. This factor structure reflects the often differing presentations of depressive symptoms in older adults with varying degrees of cognitive function and established the construct validity of the DMAS in this population. We conclude that the DMAS may be used for differentiated clinical assessment of depressive symptoms along major dimensions of depressive illness in this cohort of elderly.