cssi/SciSciGPT-SciSciNet huggingface dataset:
Net Investment in Farm Tractors: An Econometric Analysis

A wide range of assumptions about the capital deterioration and marginal factor cost of tractors has been made in previous studies. This study develops a measure of the implicit rental price of tractors which accounts for the capital structure used by farmers, the capacity depreciation of tractors, and income tax considerations. Estimates of net investment models for alternative capacity depreciation patterns are compared to those suggested by engineering considerations. The results show that the frequently used geometric decay pattern does the poorest job of explaining annual real net investment in farm tractors.
With the Help of Giants

A childhood fascination with animals, plants, and insects was aided and abetted by many giants, beginning with my parents. The Bronx High School of Science and the City College of New York (CCNY) made a solid and priceless grounding in chemistry and biology available free of charge. Abe Mazur at CCNY revealed the wonders of biochemistry and illustrated that it was possible to pursue these wonders while being paid to do so. He also directed me to Duke University Medical School for PhD work under the tutelage of Phil Handler. With the exception of a sabbatical year at Harvard with Frank Westheimer, my entire career has been spent at Duke serving under three fine and supportive chairmen: Handler, Hill, and Raetz. The premier discoveries to emanate from my laboratory have been the sulfite oxidase, the several superoxide dismutases, the manganese catalase, and the catalase/peroxidase. Many other topics piqued my interest and resulted in ∼ 400 publications. Herein I have recounted some of the circumstances surr...
Pharmacologically Targeting the P2rx4 Gene on Maintenance And Reinstatement of Alcohol Self-Administration In Rats

Genetic studies indicate that alcohol consumption associates with expression of the P2rx4 gene, a gene that codes for the P2X(4) receptor. This receptor is a subtype in the purinergic system of ligand-gated ion channels that when activated exerts excitatory effects in CNS. P2X(4) function is inhibited by alcohol and P2X(4) receptors are modulated positively by the antiparasitic agent, ivermectin. Two experiments were performed to test the ability of ivermectin to alter the behavioral effects of alcohol in rats. After alcohol exposure was achieved via the "drinking in the dark" procedure, separate groups of Sprague-Dawley rats were trained to lever press for either alcohol (10% ethanol/2% sucrose) or sucrose (3%) solutions in operant chambers. Rats were tested for maintenance of operant self-administration under a progressive ratio condition (Experiment 1) and for reinstatement of extinguished responding induced by solution presentation (Experiment 2) after ivermectin (0; 1-10mg/kg; IP) administration. Ivermectin decreased the amount of work that the animal performed to obtain reinforcers in the maintenance study, particularly in the group reinforced with alcohol, and tended to decrease reinstated lever press responding. Conditioned approach behavior (head entries) was significantly reduced by ivermectin in both experiments. Reduction in motor activity was seen during the longer maintenance sessions but not in the shorter reinstatement sessions. Results suggest some support for ivermectin-like drugs as potential treatment agents for alcohol dependence. Caution is warranted due to modest specificity on behavior reinforced by alcohol, some reduction in general activity levels, and the lack of dose-response effects.
General circulation modelling of Holocene climate variability

Results from a series of Goddard Institute for Space Studies (GISS) General Circulation Models (GCMs) are used to assess climate variability in the pre-anthropogenic Holocene, the interval following the end of the last glacial beginning roughly 11.5 kyr BP. In particular, we focus on the forced aspects of this variability. The principle forcings are orbital, solar, volcanic and events (such as the 8.2 kyr BP event). Land use and greenhouse gases also play a small role. We discuss suitable comparisons to paleo-data and the appropriateness of model experimental design for single and multiple forcing runs using time-slices and transient simulations. As an example, we focus on the response to solar and volcanic forcing in the context of the Maunder Minimum, a cool period of the late 17th century and demonstrate that although (northern) hemispheric mean temperature changes can be reasonably simulated in most models, the details of regional patterns depend more heavily on the included physics. In particular, we highlight the role of the stratosphere as well as the importance of ocean and vegetation feedbacks.
Physical modeling of PM synchronous motors for integrated coupling with Machine drives

A physical phase variable model for permanent magnet synchronous motors is proposed. This model is initiated to pursue an accurate and fast motor model for integrated motor drive simulation. Since the full finite element (FE) model may be time consuming and the direct- and quadratic-axis (dq)-model is inaccurate, the proposed physical phase variable model eliminates these deficiencies. The proposed model is a circuit model with inductance, back electromotive force (EMF), and cogging torque calculated from nonliner transient FE solutions. The main characteristics of this model are that it is as accurate as the full FE model while giving fast computational results. The Simulink implementation of the proposed model is studied. Comparisons of the proposed model with the full FE model and the dq-model are performed. The results verify the validity of the proposed model and show its practical superiority in drives applications.
The Critical Humanisms of Dorothy Dinnerstein and Immanuel Kant Employed for Responding to Gender Bias: A Study, and an Exercise, in Radical Critique.

Two humanist, critical approaches—those of Dorothy Dinnerstein and Immanuel Kant—are summarized, compared, and employed to critique gender bias in science education. The value of Dinnerstein’s approach lies in her way of seeing conventional “masculinity” and conventional “femininity” as developing in relation to each other from early childhood. Because of women’s dominance of early childcare and adults’ enduring, sexist resentment of that dominance, women become inhumanely associated with the non-adult qualities of immaturity, dependence, and childish vulnerability and punish-ability; and male human beings—to whom woman-resenting convention assigns the impossible task of absolutely triumphing over “the feminine,” childhood experience, and all human vulnerability—become inhumanely held to unachievable standards of super-hero invulnerability and god-like mental and practical infallibility. The value of Kant’s approach lies in his insistence that our sense of what is right and necessary for social progress must arise in a practically engaged and experientially full manner, rather than (1) from concepts (such as rigid ideological prescriptions) conceived as being detached from sense experience and as arising from an otherworldly, divine or quasi-divine realm of moral infallibility (such concepts being conventionally associated with “masculine” authority and leadership), or (2) from a sense of being trapped in what—in a given historical, cultural, or experiential moment—may appear as an absolute and unchangeable reality of embodied human experience (an anti-critical, anti-intellectual, and anti-progressive sense of things often associated with disempowered “feminine” experience). I demonstrate that critique integrating these approaches is useful in a science education setting.
ACOUSTIC RADIATION FROM A RECTANGULAR PLATE REINFORCED BY SPRINGS AT ARBITRARY LOCATIONS

Abstract The vibration of a simply supported rectangular plate which is reinforced by a finite number of springs at arbitrary locations is sought as a linear combination of the flexural modes of the corresponding unloaded (or simple) plate. Although these modes cannot be directly used to decouple the dynamic equations of the motion of the reinforced plate, it is still advantageous to use them as a complete set of basis functions to represent the interested quantities such as the deflection of the plate. A linear transformation is established between the two modal spaces spanned by the modes, respectively, for the reinforced and the unloaded plates. The radiation characteristics of the spring-reinforced plate are investigated by using a near field formulation. In order to reduce computational burden, a frequency interpolation technique is employed so that numerical integration now needs to be carried out only at some key frequencies. The specific radiation resistances of the basis modes are first determined as a set of invariants from which the modal radiation efficiency of the reinforced plate can be readily extracted. The effects of cross-modal coupling between the basis modes have been considered, which is necessary for an accurate determination of the modal radiation efficiency for the reinforced plate. A qualitative procedure is also described for locating the “coincidence” frequencies where the modal radiation efficiencies of the reinforced plate tend to reach their peak values.
Hepatic ablation using bipolar radiofrequency electrocautery.

Rationale and Objectives. Percutaneous methods have been used to treat primary and secondary hepatic neoplasms. In the current study, we evaluated the potential of bipolar radiofrequency (RF) electrocautery to increase in vitro liver tissue destruction when compared with monopolar RF electrocautery. Methods. Two needles (electrodes) were placed into fresh bovine liver tissue for use with bipolar electrocautery. Needle tip exposure was kept constant at 3 cm while other parameters, including treatment time, power (wattage), interneedle distance, and needle tip temperature, were changed. Pathologic and histologic correlation was performed, and tissue necrosis was weighed in grams for individual parameters. Results. There was a minimal threshold of approximately 45°C where tissue coagulation occurred. Tissue coagulation increased the longer treatment went on. Increasing temperature, wattage, or both increased tissue coagulation such that necrosis was too rapid and char formation occurred, which prevented further coagulation. For all wattages and temperatures, there was increasing tissue necrosis with increasing needle separation, until a point at which further needle separation produced less tissue necrosis. Optimizing parameters allowed tissue coagulation of greater than 30 g. Conclusion. Bipolar RF electrocautery shows promise for increasing the tissue coagulation in fresh bovine liver compared with the previously described monopolar technique.
Is splenectomy rate amongst pediatric trauma centers correlated with overall trauma related mortality

Is splenectomy rate amongst pediatric trauma centers correlated with overall trauma related mortality? Chethan Sathya, MD, Randall Burd, MD, PhD, Michael L Nance, MD, FACS, Avery B Nathens, MD, PhD, FACS Children’s National Medical Center, Washington, DC and Children’s Hospital of Philadelphia, Philadelphia, PA and Sunnybrook Health Sciences Centre and University of Toronto, Toronto, Ontario, Canada
Elections and Distributive Politics in Mubarak's Egypt: Elections and Elite Management

The long-standing conventional wisdom regarding why authoritarian regimes establish parties, hold elections, and convene legislatures is that these institutions convey an aura of legitimacy, both domestically and to the outside world. Domestically, most autocrats enjoy the power and institutional capacity to impose their policy preferences autonomously. Nevertheless, it is often preferable to rule under the cover of formal legislative institutions with ruling parties comprising a parliamentary majority. In fact, in many authoritarian regimes, there is surprising attention paid to issues of procedural integrity, even when passing the most undemocratic of laws. The existence of elections and parliaments also conveys an appearance of legitimacy to the outside world. Authoritarians reap the benefits associated with perceived liberalization through establishing institutions that appear democratic. The United States and Europe then offer aid or preferential trading arrangements in exchange for such liberalization, and international financial institutions offer cut-rate loans. A number of scholars assume or even actively promote the idea that elections confer legitimacy on authoritarian and “transitioning” regimes in Africa (Mozaffar 2002; Moehler 2005), Central Asia (Schatz 2006), China (Heberer 2006), the Arab world (Hudson 1991), and more generally (Schedler 2002). My contention, however, is that the quest for legitimacy is only half the story. There is, in fact, a more compelling explanation, namely, that elections are a tool to manage domestic political elite, upon whom the authoritarian relies for regime stability.
Puzzled: Figures on a plane

Welcome to three new puzzles. Solutions to the first two will be published next month; the third is (as yet) unsolved. In each, the issue is how your intuition matches up with the mathematics.
Propensity Score Analysis in R A Software Review

In this article, we review four software packages for implementing propensity score analysis in R: Matching, MatchIt, PSAgraphics, and twang. After briefly discussing essential elements for propens...
Universal roles of hydrogen in electrochemical performance of graphene: high rate capacity and atomistic origins

Atomic hydrogen exists ubiquitously in graphene materials made by chemical methods. Yet determining the effect of hydrogen on the electrochemical performance of graphene remains a significant challenge. Here we report the experimental observations of high rate capacity in hydrogen-treated 3-dimensional (3D) graphene nanofoam electrodes for lithium ion batteries. Structural and electronic characterization suggests that defect sites and hydrogen play synergistic roles in disrupting sp(2) graphene to facilitate fast lithium transport and reversible surface binding, as evidenced by the fast charge-transfer kinetics and increased capacitive contribution in hydrogen-treated 3D graphene. In concert with experiments, multiscale calculations reveal that defect complexes in graphene are prerequisite for low-temperature hydrogenation, and that the hydrogenation of defective or functionalized sites at strained domain boundaries plays a beneficial role in improving rate capacity by opening gaps to facilitate easier Li penetration. Additional reversible capacity is provided by enhanced lithium binding near hydrogen-terminated edge sites. These findings provide qualitative insights in helping the design of graphene-based materials for high-power electrodes.
Topology Optimization for Additive Manufacturing: Considering Maximum Overhang Constraint

Additively manufactured components often require temporary support material during the 3D printing process. In the case of polymer material process such as Fuse Deposition Modeling (FDM), the support material can be dissolved away. However in the case of metals in a selective laser melting (SLM) process, the support and component material are one in the same. Since the support structure adds both material cost and post-processing cost to every component printed, it is desired to limit or completely eliminate the need for such material. As such, it is proposed to take advantage of the maximum printable overhang angle (the angle at which the AM process requires no support material) by harnessing topology optimization as the design engine. This is accomplished through a topology optimization projection scheme, in which the angle constraint is imposed through a Heaviside projection and not applied as an explicit constraint. Solutions to two standard topology optimization problems are included and show good agreement with the overhang constraint.
Ion Dependence of Gate Dielectric Behavior of Alkali Metal Ion-Incorporated Aluminas in Oxide Field-Effect Transistors

The effect of different alkali metal ions (Li+, Na+, K+) incorporated into aluminas on the gate dielectric behavior of solution processed oxide field-effect transistors (FETs) was studied. High field-effect mobility (ca. 20 cm2·V–1·s–1), high saturation drain current (about 1 mA), and low subthreshold swing (ca. 200 mV/decade) were achieved in low-voltage (2 V), spin-coated zinc-tin-oxide (ZTO) FETs with potassium alumina (PA) and lithium alumina (LA) dielectrics, as we had previously demonstrated with sodium alumina (SA). To investigate the effect of alkali metal ion on the detailed alumina capacitance and AC conductivity response, the frequency, temperature, and thickness dependences of alumina capacitance were determined. Ion-incorporated alumina metal–insulator–metal (MIM) capacitors showed a possible electric double layer capacitor (EDLC) behavior, in contrast to what was observed for alumina itself. The frequency dependence of observed capacitance varied with the included ion. These dependences were...
A marine isolate of Pseudomonas nigrifaciens. II. Characterization of its blue pigment.

P. nigrifaciens produces a water-insoluble blue pigment on solid media which forms cuboidal crystals among the cells. The pigment was prepared by bulk harvest of isolated colonies incubated 5 days at 15°C. The cells were extracted with DMF and the extract benzene-precipitated and chromatographed over Sephadex LH-20. Analytical data were compiled leading to a provisional structure closely related to the pigments of P. indigofera and P. lemonnieri.
Review of negative papanicolaou tests : is the retrospective 5-year review necessary ?

New federal regulations require review of all available negative gynecologic smears within the previous 5 years for each patient with a current high grade squamous intraepithelial lesion (HGSIL) or above. Two university hospitals retrospectively reviewed all patients who had HGSIL or above and who had prior negative smears. During 18 months, 35,807 Papanicolaou tests were reported, from which we identified 44 patients with 80 negative smears before presenting with HGSIL or above. These 80 negative smears were rescreened and, on review, there was agreement with the original diagnosis in 66 cases (82.5%). Fourteen (17.5%) smears were reclassified: 2 unsatisfactory, 6 atypical squamous/glandular cells of undetermined significance, 3 low grade SIL, and 3 HGSIL or above. Of the 12 cases satisfactory for reclassification, 9 (75%) occurred within 2 years before the HGSIL or above. Two cases of atypical squamous/glandular cells occurred within 4 years. One case of HGSIL occurred more than 4 years before, but a negative Pap smear had been reclassified within the year before the diagnosis of HGSIL. The authors conclude that a 2-year retrospective review, which identified 75% of our false-negative cases, is an effective and efficient quality control and assurance practice.
Structure and Properties of C60@SWNT

Our recent achievement of high-yield C60@SWNT synthesis facilitates characterization by various techniques, including selected area electron diffraction (SAD) and Raman spectroscopy. The obtained SAD patterns show that interior C60 molecules sit on a simple 1-D lattice having a parameter of 1.00 nm. Simulated SAD patterns and real-space measurements both support this determination and do not indicate a lattice with a more complex basis, e.g. a dimer basis. Empty and bulk-filled SWNTs (22%, 56%, and 90% yields), each subjected to identical processing steps, were examined by room temperature Raman spectroscopy. Systematic differences are seen between the spectra of filled and unfilled SWNTs, particularly with respect to the G- and RBM-bands of the nanotubes. We present a possible explanation for this behavior.
Effect of Reye's syndrome serum on the ultrastructure of isolated liver mitochondria.

Reye's syndrome (RS) is characterized by alterations in the ultrastructure of liver mitochondria and a generalized impairment of mitochondrial enzyme activity. Serum from RS patients impairs ATP formation and oxidative phosphorylation of isolated liver mitochondria. We examined the effect of serum from four RS patients (including mild and severe illnesses) to determine whether RS serum induces quantifiable morphometric changes in isolated liver mitochondria. RS serum expands the mitochondrial matrix (matrix = 85 to 91% of cross-sectional area, compared with 65 +/- 12% with control serum, p less than .01) and in many cases the matrix is less dense, cristae are less apparent, and mitochondrial shape is irregular. After incubation with RS serum, mitochondria are also slightly larger (range = 0.563 to 0.492 micron 2) than mitochondria incubated with serum from normal controls (0.421 +/- 0.303 micron 2). These changes are similar to those observed in vivo in RS. The effect of RS serum is largely irreversible, resembling the effect of an uncoupler of oxidative phosphorylation, and corresponds to the free fatty acid concentration in the serum, especially the concentration of serum dicarboxylic acids. Addition of comparable amounts of long chain dicarboxylic acids induces an irreversible expansion and some distortion of mitochondria comparable to that after the addition of RS serum. There is no correlation between alteration in ultrastructure and the presence of salicylates in the serum samples. The results indicate that dicarboxylic acids may play a role in the changes in mitochondrial ultrastructure that characterize RS.
THE UNIQUE POSITION OF NEWFOUNDLAND IN THE CARE OF THE MENTALLY RETARDED CHILD.

Le domaine de l'arrieration mentale a suscite un renouveau d'interet et la tendance actuelle veut que l'on prenne soin de l'enfant arriere dans son propre milieu autant que possible.Selon les etudes de frequence faites ailleurs, les auteurs estiment qu'il y a au moins 2,500 enfants arrieres a Terre-Neuve. Environ 50 de ces enfants ont ete confies aux soins des ministeres de la Sante et du Bien-etre et la plupart ont ete places dans des foyers nourriciers.Les autres sont places dans leur propre collectivite et beneficient des amenagements disponibles, lesquels comprennent une clinique d'orientation de l'enfance et sept ecoles situees en divers points de la province. Ces ecoles sont dirigees par l'Association de Terre-Neuve pour l'aide aux enfants arrieres qui s'occupe d'environ 100 ecoliers.Les arrieres a Terre-Neuve semblent etre accueillis facilement dans la collectivite et les auteurs laissent entendre que cet accueil est attribuable aux caracteres culturels et geographiques de Terre-Neuve, uniques en l...
Sensational flesh: race, power, and masochism

How does (bodily) sensation become attached to (political and social) difference?This question animates Amber Musser’s book Sensational flesh: Race, power, and masochism. The answers her book provi...
Pigou in the Foreground

On 29 May 1979, The Guardian published excerpts from a forthcoming book by Richard Deacon, a pen name used by Donald McCormick. His most sensational revelation was the accusation that Arthur Cecil Pigou (18 November 1877–7 March 1959), Alfred Marshall’s successor in the Chair of Political Economy at Cambridge University, was the mysterious ‘Fourth Man’ in the Cambridge spy ring operated by the KGB. The first three were Guy Burgess, Donald Maclean, and Kim Philby, all of whom had studied at Cambridge in the early 1930s. Working as agents at the same time that they held important posts in the Foreign Office or the intelligence services — for a time, Philby was a leading candidate for chief of MI6 — they passed secret British and American intelligence to the Soviets in the early years of the Cold War. Burgess and Maclean escaped to Moscow in 1951, when they realized they faced imminent exposure. Philby, although compromised and forced to resign from MI6, continued to flourish in the British journalistic and intelligence establishment, living by his considerable charm and wits. He finally made his way to Moscow in 1963. In McCormick’s imagination, however, Pigou was the master spy of the KGB Cambridge stable.
The Criminal Justice Experience of African American Cocaine Users in Arkansas.

ABSTRACTBackground: African Americans are incarcerated at rates much higher than other racial and ethnic groups in the United States. Objectives: We sought to qualitatively explore the relationships between ongoing involvement in the criminal justice system and continued drug use in a population of urban and rural African American cocaine users in a southern state. Methods: Semi-structured qualitative interviews were conducted among African American cocaine users in Arkansas between 2010 and 2012. Participants resided in both rural (two counties located in the eastern Arkansas Mississippi delta region) and urban (the county including the capital city of Little Rock) areas. Results: Numerous important themes emerged from participants’ narratives, including chronic involvement with the criminal justice system (being a “career criminal”), continued access to drugs while incarcerated, relapse, and reincarceration and lack of access to effective drug treatment. Conclusion/Importance: The themes which emerged f...
Abiotic Tolerances in Different Life Stages of Apple Snails Pomacea canaliculata and Pomacea maculata and the Implications for Distribution

In the United States, populations of nonindigenous Pomacea spp. have been reported in at least 10 states, and the rate of spread has been greatest in the southeastern United States, particularly in Florida. Factors impacting successful establishment of molluscs include salinity, pH, and desiccation tolerance. This article reports on median survival and growth of Pomacea canaliculata and Pomacea maculata (hatchlings through adults) in 28-day trials focused on these factors with an ambient condition serving as a control (e.g., 0 = salinity control). Overall hatchlings had the lowest survival, followed by juveniles then adults. Median survival was less than 28 days for all salinity treatments greater than 16. Median survival was 28 days for all pH levels (5.5–9.5) for juveniles and adults of both species. Median survival in desiccation treatments (>80% relative humidity and wet sand or <60% relative humidity and dry sand) was 28 days for adults of both species and for juvenile P. canaliculata. The closer a treatment was to the control level, the greater the increases in shell length and width. In all treatments, snails experienced a loss in mass; the closer a parameter to the control typically resulted in the greatest loss in mass. The ability of these species to tolerate such diverse conditions will leave many systems vulnerable to invasion.
Timing of Complications Occurring Within 30 Days After Adult Spinal Deformity Surgery.

Abstract Study Design Cross-sectional study of a national surgical database. Objective To investigate the timing of complications after adult spinal deformity (ASD) surgery. Summary of Background Data There is limited data on the range of days when complications after ASD surgery occur. Methods The American College of Surgeons National Surgical Quality Improvement database was reviewed for the years 2007–2013. Inclusion criteria were adult patients (over 21 years of age) who underwent spinal fusion for ASD. Ten unique complications occurring within 30 postoperative days were examined and the median day to diagnosis was recorded. Results A total of 1,250 patients met inclusion criteria with an overall complication rate of 13.5%. The median day of diagnosis (and interquartile range) for each complication was as follows: myocardial infarction (3.5, 1–5), pulmonary embolism (4, 2–16), reintubation (4.5, 1–11), pneumonia (6, 3–9), urinary tract infection (11, 5–15), sepsis (12, 6–18.5), deep vein thrombosis (12, 6–19), deep surgical site infection (SSI; 18.5, 13–23), superficial SSI (19, 13–24), and organ space SSI (21, 17–25). The three complications that were most commonly diagnosed before hospital discharge included pneumonia, reintubation, and myocardial infarction (diagnosed before discharge on more than 70% of cases). On the other hand, superficial, deep, and organ space infection were diagnosed in less than 40% of cases before patients left the hospital. On univariate analysis, predictors of complication occurrence included older age (p = .014), instrumentation of 7–12 levels (p = .034), and instrumentation of 13 or more levels (p = .035). Conclusion Understanding the timing of specific complications after adult spinal deformity surgery is important for both patients and clinicians. Efforts in prevention of such conditions should continue, as well as heightened awareness during the periods of highest risk.
Groupwise envelope models for imaging genetic analysis

Motivated by searching for associations between genetic variants and brain imaging phenotypes, the aim of this article is to develop a groupwise envelope model for multivariate linear regression in order to establish the association between both multivariate responses and covariates. The groupwise envelope model allows for both distinct regression coefficients and distinct error structures for different groups. Statistically, the proposed envelope model can dramatically improve efficiency of tests and of estimation. Theoretical properties of the proposed model are established. Numerical experiments as well as the analysis of an imaging genetic data set obtained from the Alzheimer's Disease Neuroimaging Initiative (ADNI) study show the effectiveness of the model in efficient estimation. Data used in preparation of this article were obtained from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database.
Variability in age and size at maturation, reproductive longevity, and long-term growth dynamics for Kemp's ridley sea turtles in the Gulf of Mexico.

Effective management of protected sea turtle populations requires knowledge not only of mean values for demographic and life-history parameters, but also temporal and spatial trends, variability, and underlying causes. For endangered Kemp’s ridley sea turtles (Lepidochelys kempii), the need for baseline information of this type has been emphasized during attempts to understand causes underlying the recent truncation in the recovery trajectory for nesting females. To provide insight into variability in age and size at sexual maturation (ASM and SSM) and long-term growth patterns likely to influence population trends, we conducted skeletochronological analysis of humerus bones from 333 Kemp’s ridleys stranded throughout the Gulf of Mexico (GOM) from 1993 to 2010. Ranges of possible ASMs (6.8 to 21.8 yr) and SSMs (53.3 to 68.3 cm straightline carapace length (SCL)) estimated using the “rapprochement” skeletal growth mark associated with maturation were broad, supporting incorporation of a maturation schedule in Kemp’s ridley population models. Mean ASMs estimated from rapprochement and by fitting logistic, generalized additive mixed, and von Bertalanffy growth models to age and growth data ranged from 11 to 13 yr; confidence intervals for the logistic model predicted maturation of 95% of the population between 11.9 and 14.8 yr. Early juvenile somatic growth rates in the GOM were greater than those previously reported for the Atlantic, indicating potential for differences in maturation trajectories between regions. Finally, long-term, significant decreases in somatic growth response were found for both juveniles and adults, which could influence recruitment to the reproductive population and observed nesting population trends.
Left Ventricular False Tendons are Associated With Left Ventricular Dilation and Impaired Systolic and Diastolic Function.

Abstract Background Left ventricular false tendons (LVFTs) are chord-like structures that traverse the LV cavity and are generally considered to be benign. However, they have been associated with arrhythmias, LV hypertrophy and LV dilation in some small studies. Hypothesis LVFTs are associated with LV structural and functional changes assessed by echocardiography. Methods We, retrospectively, evaluated echocardiographic and clinical parameters of 126 patients identified as having LVFTs within the past 2 years and compared them to 85 age-matched controls without LVFTs. Results There were no significant differences in age (52 ± 18 versus 54 ± 18 years, P = 0.37), sex (55% versus 59% men, P = 0.49), race (36% versus 23% white, P = 0.07), systolic blood pressure (131 ± 22 versus 132 ± 23mmHg, P = 0.76) or body mass index (BMI, 31 ± 8 versus 29 ± 10kg/m 2 , P = 0.07) between controls and patients with LVFTs, respectively. Patients with LVFTs had more prevalent heart failure (43% versus 21%, P = 0.001). Patients with LVFTs had more LV dilation, were 2.5 times more likely to have moderate-to-severe mitral regurgitation, had more severe diastolic dysfunction and reduced LV systolic function (18% lower) compared with controls (all P P P Conclusions Our findings suggest that LVFTs may not be benign variants, and basal and middle LVFTs may have more deleterious effects. Further prospective studies should be performed to determine their pathophysiological significance and whether they play a causal role in LV dysfunction.
Fostering a Public Health of Consequence: Practical Skills and Lessons Learned

An editorial is presented which addresses the concept of a public health of consequence in America, and it mentions the author's views about how career guidance and mentorship, multisectoral work, and the ability to lead and follow can impact the careers of public health practitioners as of 2017. The role of a public health worker as a mentor is examined, along with career changes and opportunities to work in various sectors such as the government and academia.
A modified version of DVR-based multicasting with security

Reverse Path Forwarding based multicasting used in Distance Vector Multicast Routing Protocol (DVMRP) has the major drawback of generating large number of duplicate and prune packets. Use of the concept of pseudo diameter reduces the number of duplicate packets. The reason is that pseudo diameter helps in the reduction of the scope of travel of a packet. In this work a new approach of multicasting with security has been proposed. The concept of pseudo diameter has been extended to further reduce the scope of travel of a packet. Use of this new concept known as super pseudo diameter while multicasting results in significant reduction of the number of prune packets generated; hence, it guarantees even better utilization of network bandwidth.
Alzheimer’s Disease: Neurodegeneration

Alzheimer’s disease (AD) is a chronic progressive neurodegenerative disorder characterized pathologically by the presence of abnormal protein aggregates in neurons and the extracellular space of the central nervous system. The signature lesions of the AD brain are the neurofibrillary tangle and the senile plaque, an extracellular structure composed largely of accumulations of filaments of a small peptide, amyloid β-protein (Aβ). The discovery of mutations in the amyloid precursor protein gene (APP) in early-onset forms of AD and triplication of APP on chromosome 21 in Down syndrome led to the unequivocal evidence that abnormal processing of APP alone is sufficient to cause AD. Transgenic animal models replicate many, but not all, of the pathological features seen in the human disease. These discoveries have opened up new avenues of research into Aβ and tau fibrillogenesis in mechanisms of brain dysfunction and neurodegeneration. The identification of disease-specific abnormal protein aggregates has illuminated mechanisms of pathogenesis and provided insights for potential therapeutic modification.
Institutional Erosion and Economic Stagnation in Puebla, 1999–2011

This chapter describes how the first decade of the twenty-first century saw the continuation of a decades-long pattern of contentious relations between local government and business in Puebla. The administration of Melquiades Morales (1999–2005) managed to keep the peace with the private sector, aided by the governor’s selective provision of favors. However, conflict broke out again during the turbulent administration of Mario Marin (2005–2011), who immediately became engulfed in a major political scandal after taking office. In order to stave off opposition from local business, Marin attempted to co-opt segments of the business community through the distribution of public contracts and other benefits, exacerbating divisions within the private sector and leading to a further deterioration of governance in the state. In this context, attempts at public-private cooperation faltered, and Puebla once again failed to diversify its economy or upgrade existing industries beyond the auto enclave.
Population-based evaluation of treatment patterns and survival of localized prostate cancer (CaP) patients with high prostate-specific antigen (PSA).

e16008 Background: Overtreatment of patients with indolent CaP is widely reported, but many patients have aggressive and potentially life-threatening CaP. We examined patterns of primary treatment ...
Miniaturized ring-down spectrometer for CubeSat-based planetary science.

A robust, miniaturized cavity ring-down spectrometer has been developed as a laboratory demonstration model for future CubeSat deployments of near- and mid-infrared spectrometers for in situ planetary science. The spectrometer is compact enough to ensure compatibility with standard CubeSat spacecraft buses, with a probed gas volume of less than 2.5 cc to ease mass, volume, and power requirements of sample gas handling subsystems. When operated at 1.39 μm for water vapor isotope measurements, a noise-equivalent absorption coefficient of 3.7×10−9 cm−1 Hz−1/2 is obtained. Oxygen isotope measurements were performed to demonstrate scanning performance. The spectrometer has been designed to use only components with functional equivalents throughout the 1–5 μm range to maintain flexibility across a wide array of planetary science targets. Preliminary results from a 3.27 μm implementation intended for methane measurements are also presented.
Uncovering the Hidden Factors that Could Compromise Equitable and Effective Engineering Education

Literacies are central to the social and cultural practices that are intertwined with identities, who gets to participate in engineering, and the knowledge that is valued in the discipline. However, identifying these literacies is not a straightforward process for engineering faculty. The purpose of this workshop is to help engineering faculty identify equity-oriented literacies that challenge hidden curriculum frameworks in engineering and influence engineering identity formation.
Using Supervised Machine Learning in Automated Content Analysis: An Example Using Relational Uncertainty

The goal of this research is to make progress towards using supervised machine learning for automated content analysis dealing with complex interpretations of text. For Step 1, two humans coded a s...
Transitory Voices: The Journey From Urban High Schools to an Early College Academy Program:

A mixed-methods approach of sequential explanatory strategy was used to explore experiences of 37 students related to an Early College Academy (ECA) program and their high schools. Data consisted o...
The association between e-cigarette use and asthma among never combustible cigarette smokers: behavioral risk factor surveillance system (BRFSS) 2016 & 2017

E-cigarette use prevalence has grown rapidly in the US. Despite the popularity of these products, few acute exposure toxicity studies exist, and studies on long-term pulmonary health effects are limited. E-cigarette users who are never combustible cigarette smokers (sole users) constitute a unique group of young adults that may be at increased risk of bronchial hyperreactivity and development of asthma. Given the public health concern about the potential pulmonary health effects of sole e-cigarette use, we aimed to examine the association between e-cigarette use and asthma among never combustible cigarette smokers. We pooled 2016 and 2017 data of the Behavioral Risk Factor Surveillance System (BRFSS), a large, cross-sectional telephone survey of adults aged 18 years and older in the U.S. We included 402,822 participants without any history of combustible cigarette smoking (defined as lifetime smoking < 100 cigarettes) and with complete self-reported information on key variables. Current e-cigarette use, further classified as daily or occasional use, was the primary exposure. The main outcome, asthma, was defined as self-reported history of asthma. We assess the relationship of sole e-cigarette use with asthma using multivariable logistic regression adjusting for age, sex, race, income, level of education and body mass index. Of 402,822 never combustible cigarette smokers, there were 3103 (0.8%) current e-cigarette users and 34,074 (8.5%) with asthma. The median age group of current e-cigarette users was 18–24 years. Current e-cigarette use was associated with 39% higher odds of self-reported asthma compared to never e-cigarette users (Odds Ratio [OR], 1.39; 95% confidence interval: 1.15, 1.68). There was a graded increased odds of having asthma with increase of e-cigarette use intensity. The odds ratio of self-reported asthma increased from 1.31 (95% confidence interval: 1.05, 1.62) in occasional users to 1.73 (95% confidence interval: 1.21, 2.48) in daily e-cigarette users, compared to never e-cigarette users. Our findings from a large, nationally representative survey suggest increased odds of asthma among never combustible smoking e-cigarette users. This may have potential public health implications, providing a strong rationale to support future longitudinal studies of pulmonary health in young e-cigarette-using adults.
Coupled NO and C3H6 Trapping, Release and Conversion on Pd-BEA: Evaluation of the Lean Hydrocarbon NOx Trap

Automotive emission control catalysts are not effective in eliminating CO, hydrocarbons, and NOx during engine cold-start (below 200°C). In this study the effectiveness of coupled low-temperature NOx and C3H6 trapping and conversion on a model Lean Hydrocarbon NO¬x Trap (LHCNT) consisting of a washcoated Pd/BEA monolith was examined. Transient uptake and release experiments were conducted to obtain insight regarding competitive adsorption, release temperature, conversion activity, and water impact. NO and C3H6 uptake were found to be mutually inhibitive due to competition for adsorption on Bronsted acid sites (BAS). During desorption, the existence of multiple NO sorption sites was established. Although C3H6 inhibited NO adsorption on some of these sites, it delayed NO¬x desorption to higher temperatures. Furthermore, above 200°C Pd/BEA was able to catalyze the oxidation of stored hydrocarbons and exhibited NOx reduction activity. Addition of water inhibited both NOx and C3H6 uptake, but the inhibition wa...
Exploring injury severity in head-on crashes using latent class clustering analysis and mixed logit model: A case study of North Carolina

Abstract Although only 2 % of crashes are head-on crashes in the United States, they account for over 10 % of all crash-related fatalities. This study aims to investigate the contributing factors that affect the injury severity of head-on crashes and develop appropriate countermeasures. Due to the unobserved heterogeneity inherent in the crash data, a latent class clustering analysis is firstly conducted to segment the head-on crashes into relatively homogeneous clusters. Then, mixed logit models are developed to further explore the unobserved heterogeneity within each cluster. Analyses are performed based on the data collected from the Highway Safety Information System (HSIS) from 2005 to 2013 in North Carolina. The estimated parameters and associated marginal effects are combined to interpret significant variables of the developed models. The proposed method is able to uncover the heterogeneity within the whole dataset and the homogeneous clusters. Results of this research can provide more reliable and insightful information to engineers and policy makers regarding the contributing factors to head-on crashes.
Development of an Unmanned Surface Vehicle for Harmful Algae Removal

In this paper, we introduce a small and low-cost unmanned surface vehicle (USV), the SMARTBoat 5, capable of removing harmful algal blooms (HABs), which are a rising environmental issue worldwide. The developed USV is a hovercraft type, operated by two propellers with duct fans; it is able to freely move even in shallow water and to approach shorelines. For eco-friendly, immediate, and safe control of algae, the USV is equipped with a novel water suction mechanism that enables it to actively collect algae without physical contact. In addition, it is equipped with a mesh net-based algae filter system that is easily disassembled and replaced. The USV system is supported by the Robot Operating System (ROS) for expandability and use in diverse applications. The performance of the proposed water suction mechanism and USV platform overall are validated through computational fluid simulation (CFD) and experiments in both lab and real environments.
Non-GCA modeling of near threshold I-V characteristics of DG MOSFETs

Author(s): Ren, Zhongjie | Advisor(s): Taur, Yuan | Abstract: It is well known that the velocity saturation behavior is not negligible in the shorter channel length and the gradual channel approximation (GCA) fails to generate reasonable I-V characterisitics of MOSFETs for both n = 1 and n = 2 models. Therefore, the non-GCA model has been developed to solve this issue by adding the ∆Q (Source-Drain induced part for mobile charges) term which is absent in the conventional GCA models and exhibits an excellent performance for above threshold region (Vgs-Vtg0.27V) modeling. However, the near threshold modeling (Vgs-Vtl0.1V) is not ideal in the previous non-GCA model with linear Qi(V) when compared with TCAD simulations owing to the failure of matching the Qi(V) (Gate induced part for mobile charges) profile in that region. In this work, a more rigerous non-GCA model with piecewise Qi(V) which can successfully approach I-V behaviors of DG MOSFETs in the near threshold region for n = 1 and n = 2 has been proposed by extending the continous, analytical GCA model of Qi(V) to obtain negative values. In addition, relative favorable above threshold I-V characteristics can be calculated by utilizing the proposed non-GCA model as well.
A mineralogical and chemical investigation of road dust in Philadelphia, PA, USA

Road dust was investigated within Philadelphia, a major United States city with a long history of industrial activities, in order to determine pollution levels. Almost all of the investigated minor elements were enriched relative to the continental crust. Furthermore, mean concentrations of Cr, Co, Cu, and Pb were high compared with those reported in cities in other countries. Lead pollution should be investigated further in Philadelphia, where 8 of the 30 sample sites, including those heavily trafficked by civilians, were at or above the EPA’s child safety threshold for Pb in bare soil. High Spearman correlations between Zn and Cu, Zn and Cr, Cu and Cr, and Sn and V, as well as factor analysis of minor elements suggests that the primary sources of these elements were anthropogenic. Potential sources included the breakdown of alloys, non-exhaust traffic emissions, paint, smelting, and industry. We found that higher organic content in road dust may be related to higher traffic densities, which could be due to tire-wear particles. Additionally, higher mean concentrations of Fe, Cr, Cu, and Zn were found at sites with elevated traffic densities. Land use impacted some of the elements not influenced by traffic density, including Co, Sn, and Pb. Bulk mineral content was similar across different land uses and traffic densities and, thus, did not appear to be influenced by these factors. Our research emphasized the complexity of road dust and utilized a more comprehensive approach than many previous studies. This study established fundamental groundwork for future risk assessment in Philadelphia, as it identified several key pollutants in the city. Overall, this assessment serves as an informative reference point for other formerly heavily industrialized cities in the USA and abroad.