cssi/SciSciGPT-SciSciNet huggingface dataset:
The seed-storing corvid Clark's nutcracker learns geometric relationships among landmarks

Many animals regularly return to particular locations such as hives, nests, wintering grounds or cache sites. This ability clearly implies that animals possess information that allows them to find a route from their current location to their goal. However, the nature of this information is, in many cases, unknown. One particularly important issue is whether this information encodes at least some of the geometric relationships among real-world objects, which would meet a strict definition of a cognitive map1,2. Are animals sensitive to such geometric relationships? Although there is clear evidence that animals can learn vectors that represent a goal location in terms of absolute distance and direction to a landmark, there is little evidence of any ability to extract abstract geometric rules3,4,5,6,7,8. Here we report data demonstrating that the corvid Clark's nutcracker (Nucifraga columbiana) can learn to find the point halfway between two landmarks that vary in the distance that separates them. This learning is based on a general principle, as the birds correctly find the halfway point when the landmarks are presented with new distances between them. This demonstrates the ability to find a point defined not by the relationship between a goal and a landmark but by the relationship between landmarks. Further experiments demonstrate that there were two distinct processes involved in locating the halfway point, the use of directional bearings to find the (hypothetical) line connecting the landmarks and finding the correct place along that line.
High-resolution Digital Mapping of N-Methylpurines in Human Cells Reveals Modulation of Their Induction and Repair by Nearest-neighbor Nucleotides

N-Methylpurines (NMPs), including N7-methylguanine (7MeG) and N3-methyladenine (3MeA), can be induced by environmental methylating agents, chemotherapeutics, and natural cellular methyl donors. In human cells, NMPs are repaired by the multi-step base excision repair pathway initiated by human alkyladenine glycosylase. Repair of NMPs has been shown to be affected by DNA sequence contexts. However, the nature of the sequence contexts has been poorly understood. We developed a sensitive method, LAF-Seq (Lesion-Adjoining Fragment Sequencing), which allows nucleotide-resolution digital mapping of DNA damage and repair in multiple genomic fragments of interest in human cells. We also developed a strategy that allows accurate measurement of the excision kinetics of NMP bases in vitro. We demonstrate that 3MeAs are induced to a much lower level by the SN2 methylating agent dimethyl sulfate and repaired much faster than 7MeGs in human fibroblasts. Induction of 7MeGs by dimethyl sulfate is affected by nearest-neighbor nucleotides, being enhanced at sites neighbored by a G or T on the 3′ side, but impaired at sites neighbored by a G on the 5′ side. Repair of 7MeGs is also affected by nearest-neighbor nucleotides, being slow if the lesions are between purines, especially Gs, and fast if the lesions are between pyrimidines, especially Ts. Excision of 7MeG bases from the DNA backbone by human alkyladenine glycosylase in vitro is similarly affected by nearest-neighbor nucleotides, suggesting that the effect of nearest-neighbor nucleotides on repair of 7MeGs in the cells is primarily achieved by modulating the initial step of the base excision repair process.
TWO RANDOMIZED CONTROLLED TRIALS OF VIRUCIDAL NASAL TISSUES IN THE PREVENTION OF NATURAL UPPER RESPIRATORY INFECTIONS

Two six-month randomized, controlled double-blind trials of the efficacy of virucidal nasal tissues in the prevention of natural colds were conducted in Charlottesville, Virginia, between 1983 and 1986. Tissues impregnated with malic and citric acids and sodium lauryl sulfate were used in both trials. Placebo tissues contained saccharin in the first trial and a mixture including succinic acid in the second. A total of 186 families were evaluable after completion of trial I, and 98 families were evaluable in trial II. The antiviral tissues were associated with 14 and 5% relative reductions in the overall rate of colds in the first and second trials, respectively. In the first study, this appeared to be due to an appropriate fall in secondary illnesses with a relative reduction in the ratio of secondary to primary illnesses of 32%. In trial II, however, the small and statistically insignificant reduction was primarily due to a drop in the rate of primary illness (which cannot be attributed to tissue efficacy), and the ratio of secondary to primary illness was actually 5% higher in the group with active tissues than in the placebo group. We conclude that when rigorously used in a study protocol, virucidal tissues may offer a modest reduction of secondary colds in the home, but for reasons currently unknown, do not have a major effect on the overall rate of colds.
X-ray Absorption Spectroscopy Studies of the Local Atomic and Electronic Structure of Iron Incorporated into Electrodeposited Hydrous Nickel Oxide Films†

The authors have utilized X-ray absorption fine structure (XAFS) spectroscopy to investigate the local atomic and electronic structure of iron incorporated into electrodeposited nickel hydroxide films. It was found that cathodic codeposition from a solution containing Fe(II) and Ni(II) ions results in iron occupying Ni lattice sites in {alpha}-Ni(OH){sub 2}. The X-ray absorption near edge structure (XANES) shows that Fe is present as Fe(III) ions in the cathodically codeposited film. Analysis of the extended X-ray absorption fine structure (EXAFS) shows that Fe is coordinated to oxygen at {approximately}2.00 {angstrom} and to Ni at {approximately}3.11 {angstrom}. This Fe-O bond length is smaller than the Fe(II)-O bond distance found in Fe(OH){sub 2} ({approximately}2.10 {angstrom}) but is in good agreement with the average Fe(III)-O bond distance found in FeOOH ({alpha}, {gamma}). The Fe-Ni bond distance is in agreement with that of the Ni(II)-Ni(II) bond distance found in {alpha}-Ni(OH){sub 2}. Moreover, the radial structure function (RSF) around Fe shows a distinct peak at {approximately}5.8 {angstrom}, which is a fingerprint of the brucite ({alpha}-Ni(OH){sub 2}) structure. On anodic oxidation of the codeposited film in KOH, the workers found that the Fe ions occupied Ni lattice sites in {gamma}-NiOOH. The XANES shows that the Fe edgemore » shifts to higher energy values, indicating an increase in the oxidation state of Fe on charging. Analysis of the EXAFS data shows that Fe is coordinated to oxygen at {approximately}1.94 {angstrom} and to Ni at {approximately}2.84 {angstrom}. The latter value is in good agreement with the Ni(IV)-Ni(IV) bond length found in {gamma}-NiOOH. The RSF around Fe in the oxidized film shows a distinct peak at {approximately}5.4 {angstrom}, just as in the RSF of Ni in {gamma}-NiOOH. The Fe-O bond distance of {approximately}1.94 {angstrom} is in good agreement with the Fe(IV)-O bond distance found in SrFeO{sub 3}. The results strongly suggest that the Fe ions in the oxidized film are nominally tetravalent but with the Fe-O bond possessing a high degree of covalency.« less
The ink of Aplysia dactylomela (Rang, 1828) (Gastropoda: Opisthobranchia) and its role as a defensive mechanism

Abstract The defensive mechanisms of opisthobranch molluscs have received much attention in recent years. The sea hare Aplysia dactylomela (Rang, 1828) is known to secrete a purple ink which might serve as a defensive mechanism. The study was designed to determine if the ink would repel potential predators by being distasteful and/or noxious to them. Tests in aquaria exposed scavenging crabs to fish tissue (local baitfish) and to sea hare tissue, with and without ink present. Results indicate that the ink serves a defensive function by repelling the crabs. While the crabs would feed on A. dactylomela, they avoided the sea-hare tissue once ink was present in the surrounding water. Inking behavior of A. dactylomela is one of several means of defense which enables these animals to effectively avoid most predation.
On the significance of argon release from biotite and amphibole during 40Ar/39Ar vacuum heating

The nature of Ar release from biotite and amphibole is addressed via vacuum-heating experiments followed by measurements of 40Ar loss and unit cell parameters and scanning electron microscope observations of the heated specimens. 40Ar diffusion during hydrothermal heating was previously reported for the studied biotite and amphibole specimens allowing direct comparison to the Ar loss kinetics from vacuum heating. The results demonstrate conclusively that volume diffusion is not the mechanism controlling Ar loss during normal 40Ar/39Ar measurements. These hydrous minerals also suffer weight loss and irreversible structural changes in the range 600 to 800°C. Moreover, biotite suffers morphological modifications dramatically expressed by splitting along the basal cleavage. A few experiments on muscovite suggest similar weight loss and splitting effects. The behavior of these minerals has important implications for the interpretation of 40Ar/39Ar step-heating data. The Ar-loss kinetics of 40Ar/39Ar experiments cannot be used to calculate diffusion coefficients and it is inappropriate to estimate closure temperatures from such data. The morphological changes will not permit the meaningful resolution of “fossil” Ar gradients which may have been present in the initial grains.
A social-cognitive, attributional model of personal goals: An empirical evaluation.

A model of cognitive and affective antecedents and consequences of personal goals, which integrates constructs from social-cognitive and attribution theories, was examined. Data were gathered before and after course examinations in a large university class. Hierarchical and moderated regression analyses supported the model indicating that (1) relationships between self-efficacy, goals, and performance were positive during repeated trials over 4 1/2 months in a naturally occurring setting; (2) the stability dimension of causal attributions moderated the relationship between goal-performance discrepancies and self-efficacy; and (3) the locus of causality dimension of causal attributions moderated the relationship between goal-performance discrepancies and affective responses.
Subcutaneous adrenaline infiltration in paediatric burn surgery

Paediatric burn surgery may be associated with significant blood loss and postoperative pain. To investigate methods of reducing these symptoms, we studied a prospective series of 29 children with small to medium sized burns. Presurgically both the burn wound and split skin graft donor sites were injected with a 1:500 000 adrenaline solution, to which bupivicaine had been added. No patient required blood transfusion and no patient developed systemic side effects from the injected solution. Four patients required parenteral analgesia, two in the immediate postoperative period and two at first dressing change. In all other patients pain was controlled with oral analgesia alone. Mean graft take in our series was 95%, indicating that this technique does not compromise burn depth assessment, nor impair graft survival.
Feasibility of Smartphone-Based Education Modules and Ecological Momentary Assessment/Intervention in Pre-bariatric Surgery Patients

Bariatric surgery is the most effective means of long-term weight loss. Knowledge gaps and lack of engagement in pre-operative patients can result in suboptimal outcome after surgery. Mobile technology, utilizing ecological momentary assessment (EMA)/intervention (EMI), has shown tremendous promise in changing behaviors. The primary objective of the study is to assess feasibility of using smartphone app with EMA/EMI functionality to prepare patients for bariatric surgery. Subjects seeking primary bariatric surgery were provided a smartphone app containing video-based education modules with linked assessments to evaluate mastery of topic. Subjects received algorithmic EMA text messages soliciting a response regarding lifestyle behavior. Upon answering, subjects received tailored EMI text messaging supporting healthy lifestyle. Thirty subjects (27 female and 3 male), with age of 41.3 ± 11.4 years and BMI of 46.3 ± 7.4 kg/m2 were enrolled. Twenty subjects completed the study. Ten subjects withdrew. On average, seven out of nine education modules were completed (70.9 ± 27.3 %), and 37.8/123 EMA were answered (30.7 ± 21.7 %), with response time of 17.4 ± 4.4 min. Subjects reported high satisfaction with the app. Many felt that the app fit into their routine “somewhat easily” or “very easily” (n = 12), had “perfect” amount of EMA messages (n = 8), and was very helpful in preparing for surgery (n = 7). This study is the first to reveal the feasibility of using a smartphone app in the education and engagement of patients prior to bariatric surgery. The app was well-received based on subject satisfaction scores and revealed trends toward positive behavior change and increased weight loss. Randomized trials are necessary to delineate true efficacy.
THE EFFECTS OF A GOOD‐BEHAVIOR CONTRACT ON THE CLASSROOM BEHAVIORS OF SIXTH‐GRADE STUDENTS1

The effects of a good-behavior contract on the on-task behavior, disruptive behavior, daily assignment completion, and weekly grades of four sixth-grade students were examined in a public school classroom. The contract consisted of presenting the students with a list of good conduct and assignment completion goals and a list of disruptive behaviors coupled with a list of rewards and penalties that could be earned. The rewards and penalties made use of existing facilities and classroom privileges. At the beginning of each morning work period, the teacher negotiated the good-behavior contract with each experimental subject. During the negotiations, the teacher emphasized student self-management and encouraged each student to earn a reward by achieving the good-conduct goals and completing the contract assignments. An isolated work area was provided to allow students the opportunity to remove themselves from their desks for a fixed period of 15 min. At the end of the work period, the teacher determined whether each student earned a choice of reward or penalty dependent on assignment completion and whether the teacher had observed disruptive behaviors. Thus, the contract permitted the student to negotiate the goal behaviors and contingencies with the teacher. Throughout the study, the students were in agreement with the teacher on whether a choice of reward or penalty had been earned. The contract was introduced for different children at different times, constituting a multiple-baseline analysis. On-task behavior and daily assignment completion increased, weekly grades were higher, and disruptive behavior decreased when the contract was in effect. Three contrast subjects were selected from the class as model students who consistently produced acceptable assignments and who did not engage in high rates of disruptive and/or off-task behaviors. When the contract was in effect for the experimental subjects, their performance compared favorably with the contrast subjects, who never received the daily contract. The results demonstrated that the contract was effective within the confines of the facilities and contingencies readily available in a public school classroom setting.
Is Heparin-Induced Platelet Activation an Unrecognized Cause of Thrombosis in Chronic Dialysis Patients?:

Despite an increase in vaso-occlusive disorders and routine exposures to large quantities of heparin, chronic dialysis (CD) patients have not been studied for the presence of heparin-induced platelet activation (HIPA). Measurement of platelet aggregation and adenosine triphosphate release was performed at hepa rin concentrations of 0.1 U/mL and 100 U/mL using platelet-poor plasma (PPP) from 90 nonthrombocytopenic CD patients; 72 patients received heparin over prolonged periods (108 ±15 weeks); 18 patients received no heparin for two months prior to study.Results: PPP from 1 hemodialysis (HD) patient stimulated strong ( > 19%) platelet activation at both 0.1 and 100 U/mL heparin concentrations. Four pa tients (4.4%) demonstrated intermediate (10-19%) platelet activation in the presence of 0.1 U/mL but not 100 U/mL heparin concentrations. Eighty-five patients demonstrated no platelet activation ( < 10%) at either heparin concen tration.Conclusion: (1) None of the 90 dialysis patients met the strict laborato...
Guidelines for fluid modeling of dense gas cloud dispersion

Abstract Fluid modeling experiments can predict the behavior of complex dispersion phenomena associated with the dilution of flammable or toxic dense gases after inadvertent release. Such studies are desirable because variables can be controlled at will with great savings in time and expense over full-scale tests. The reliability and value of fluid modeling experiments will depend upon proper applications of similitude laws, the selection of appropriate instrumentation and test facilities, and the documentation of the results. This paper proposes guidelines for future fluid modeling expernnents of dense gas cloud dispersion. Performance envelopes are presented which bracket the “safe” regions in similitude parameter space for reliable model results. Recommendations are made for a minimum experimental program and associated documentation.
Effects of Visual Biofeedback Using a Laser Beam on the EMG ratio of the Medial and Lateral Vasti Muscles and Kinematics of Hip and Knee Joints during a Squat Exercise

[Purpose] The purpose of this study was to examine the effects of visual biofeedback on the EMG ratio of the medial and lateral vasti muscles and on the lower extremity joint angles during squat exercises performed by subjects with femoral anteversion. [Subjects] Seventeen subjects (5 men, 12 women) with femoral anteversion participated in this study. [Methods] Subjects performed a double-leg squat with and without visual biofeedback using a laser beam fixed to a patella strap. The peak angles of hip internal rotation and knee valgus were analyzed using a 3D motion analysis system, and the vastus medialis oblique/vastus lateralis (VMO/VL) activity ratio was calculated using the value recorded by surface electromyography during the squat exercises. [Results] Significant decreases were found in the hip internal rotation angle and knee valgus angle, and a significant increase in the VMO/VL activity ratio was observed on the dominant side when performing a double-leg squat with visual biofeedback using a laser beam. [Conclusions] We suggest that laser-beam visual biofeedback would be used as an effective for improving VMO muscle strength and reducing the angle of hip internal rotation and knee valgus during squat exercises.
Structurally preserved fossil plants from Antarctica. I: Antarcticycas, gen. nov., a Triassic cycad stem from the Beardmore Glacier area

Silicified stems with typical cycadalean anatomy are described from specimens collected from the Fremouw Formation (Triassic) in the Transantarctic Mountains of Antarctica. Axes are slender with a large parenchymatous pith and cortex separated by a narrow ring of vascular tissue. Mucilage canals are present in both pith and cortex. Vascular tissue consists of endarch primary xylem, a narrow band of secondary xylem tracheids, cambial zone, and region of secondary phloem. Vascular bundles contain unito triseriate rays with larger rays up to 2 mm wide separating the individual bundles. Pitting on primary xylem elements ranges from helical to scalariform; secondary xylem tracheids exhibit alternate circular bordered pits. Traces, often accompanied by a mucilage canal, extend out through the large rays into the cortex where some assume a girdling configuration. A zone of periderm is present at the periphery of the stem. Large and small roots are attached to the stem and are conspicuous in the surrounding matrix. The anatomy of the Antarctic cycad is compared with that of other fossil and extant cycadalean
Bone microstructure of the Upper Cretaceous theropod dinosaur Troodon formosus

ABSTRACT The bone microstructure of three third metatarsals and two tibiae of differing sizes from Troodon formosus was examined. Bone in T. formosus passed through three ontogenetic stages: rapid fibro-lamellar, moderate lamellar-zonal, and slow avascular lamellar growth. Highly-vascularized fibro-lamellar bone accounted for the majority of growth, with adult size possibly being reached in 3 to 5 years. No significant growth occurred after T. formosus reached a body weight of roughly 50 kg (femur: tibia length 310:425 mm). Abundant vasculature together with dense Haversian bone suggests T. formosus had a relatively high metabolism. Other gross morphological features (large brain, large eyes, cursorial adaptations including high tibia: femur ratio) would indicate T. formosus was very active and possibly endothermic.
Reduced adverse effects on Si thin film solar cells caused by growth chamber air exposure

Abstract The cost of photovoltaic (PV) energy is reduced by increasing solar cell power conversion efficiency and decreasing manufacture cost. An effective way of lowering the cost of Si thin film solar cells (TFSC) is to grow panels on large-area substrates. In this paper we study the effect of air residual to Si TFSC grown on 5.7 m 2 glass in plasma-enhanced chemical vapor deposition (PECVD) chambers. Structural and chemical analysis show that oxygen incorporated into the Si films behaved as impurity dopant in the hydrogenated microcrystalline Si (μc-Si) layers and reduced the efficiency of amorphous Si (a-Si)/μc-Si tandem junction solar cells when the film had oxygen concentration >2×10 19 atoms/cm 3 . Higher oxygen content further suppressed the μc-Si crystallization. We found that hydrogen plasma treatment of process chamber before Si film deposition effectively reduced the adverse effects of air exposure and improved both film quality and solar cell performance. The hydrogen-treated chamber produced contamination-free, solar cells with consistent, initial efficiency >10%.
Systematic Manipulation of Student Pacing, the Perfection Requirement, and Contact with a Teaching Assistant in an Introductory Psychology Course

Which of these three major features of PSI is most responsible for its effectiveness? The answer depends in part upon the criterion of effectiveness employed.
Polarized Emission from KI: Tl at 12°K

KI: Tl was excited with linearly polarized light in each of the four impurity-absorption bands. At temperatures below 30\ifmmode^\circ\else\textdegree\fi{}K, the emission was strongly polarized in some of the emission bands. Excitation in the $A$ band yields polarized emission in the 3356-\AA{} band. Excitation in the $B$ and $C$ absorption bands yields polarized emission in the 2870- and 2783-\AA{} emission bands, respectively, and no detectable polarization in the 3078-, 3356-, or 4300-\AA{} emission bands. These facts are interpreted using a model previously introduced for thallous-ion emission.
A radioimmunoassay for physostigmine in biological fluids and tissues.

Abstract Antibodies were produced in rabbits immunized with physostigmine conjugated to bovine serum albumin (BSA) by two different methods: a diazo immunogen coupled to BSA with carbodiimide and a Mannich coupled immunogen. Both immunogens produced antibodies that could be used to develop sensitive and specific radioimmunoassays (RIA) for physostigmine. The limit of detection of the RIA is 100 pg of physostigmine in plasma or tissue homogenates (1.0 ng ml −1 ), without the need for an extraction procedure. The interassay and intraassay coefficients of variation were
Autoradiographic localization of a calcium channel antagonist, [3H]nitrendipine, binding site in rat brain

Abstract [ 3 H]Nitrendipine, a calcium antagonist, binds in a saturable fashion ( K d = 1.4 nM, B max = 28 pmol/g tissue) to an apparent single class of sites in rat brain sections. Nifedipine and nitrendipine are potent displacers of [ 3 H]nitrendipine binding while verapamil and D-600 are almost inactive. The autoradiographic distribution of [ 3 H]nitrendipine binding shows high concentrations of sites in the hippocampus, in superficial layers of the cortex, in the external plexiform layer of the olfactory bulb and in the cerebellum. Lower levels are found in the striatum and the hypothalamus. Very low densities are observed in most of the remaining areas. The characteristic distribution of [ 3 H]nitrendipine binding sites may help to reveal the mechanism by which calcium regulates brain functions.
A noninvasive positron computed tomography technique using oxygen-15--labeled water for the evaluation of neurobehavioral task batteries.

A technique is described that provides information about relative cerebral responses to differing neurobehavioral tasks in normal subjects studied with positron computed tomography and oxygen-15-labeled water. Simulation studies demonstrate that this technique is sensitive to changes in true local CBF within a physiological range and tends to underestimate relative flow changes at high flow values (>30 ml min−1 100 g−1) and to overestimate these changes for flow values of <25 ml min−1 100 g−1. Image acquisition times of 60 s following the arrival of oxygen-15-labeled water in the brain were the most accurate for identifying such relative changes between radioisotope administrations and were not limited by statistical noise from total image counts. Studies in normal volunteers indicate that the technique is highly reproducible, demonstrating a coefficient of variation for small (<2 cm2) regions of 2.98 between studies in the same state. Visual stimulation studies in normal volunteers demonstrated relative ...
Diverse effects of estradiol-17β: Concurrent suppression of appetite, blood pressure and vascular reactivity in conscious, unrestrained animals

Abstract Evidence from epidemiological and clinical investigations have suggested a relationship between estrogen-containing oral contraceptives and hypertension. The present series of studies, however, documents the ability of estradiol-17β, a natural ovarian estrogen, to lower resting blood pressure and pressor responses to norepinephrine in conscious, unrestrained guinea pigs. Arterial measurements were made of resting blood pressure and heart rate, plus pressor responses to intravenous infusions of 1.56 μg norepinephrine. Injection of 30 μg estradiol-17β reduced resting pressures up to 12% and pressor responses up to 20% in the interval from 12 to 48 hours postinjection. The estradiol treatment also significantly and reversibly lowered food intake, water intake, and body weight. These effects could be induced by either 3 or 30 μg of estradiol benzoate for up to 4 days if estradiol treatment was continued. Parallel studies indicated that NE-induced contractions of the isolated aorta were markedly reduced by pretreatment with estradiol. These studies indicate that natural ovarian estrogens may reduce blood pressure by reducing the contractility of the arterial smooth muscle.
Measuring the Effects of Municipal Zoning Regulations: A Survey

Over the past 25 years a large literature has developed that attempts to measure the impact of zoning regulations on real estate markets. This vast zoning literature is also quite diverse; studies ...
Structure of Stratospheric Wave Responses to ENSO Convection

Abstract Generalized maximum covariance analysis (GMCA) has been developed and applied to diagnosing the relationships between ENSO tropospheric heating variations and tropical stratospheric waves. GMCA identifies the most important patterns of covariability between interannual tropospheric heating variations and eddy zonal and meridional velocities, temperatures, and ozone mixing ratios in the tropics between 200 and 10 hPa. The first two sets of GMCA time coefficients have variations that are strongly related to ENSO and are highly correlated at a lag of about a year. The diagnosed spatial patterns have broad wavenumber 1 characteristics, which are associated with ENSO. These dominant modes of heating variations are linked to a rich three-dimensional pattern of stratospheric eddy perturbations over a wide range of lags. Generally, all major features propagate slowly to the east along with the tropospheric heating anomaly. In addition there is strong vertical coherence such that the strongest anomalies t...
“I Am Looking for a Good Western …”: The Western in the American Public Library of the 21st Century

Western fiction, in the view of many authors and publishers in that field as well as librarians, has become severely marginalized and difficult to select. This study examines the collections of 45 select public libraries to determine the degree to which 38 Spur Award–winning titles were included in popular fiction collections.
Predicting accuracy of comprehension from the relative difficulty of the material

Abstract The functional relationship between the relative difficulty of passages and the degree to which they are comprehended was investigated. Relative difficulty was defined as the accuracy level (A l ) of the reader minus the difficulty level (D l ) of the material when both were measured in grade equivalent (GE) units; relative difficulty was A l — D l . A total of 568 students in grades 3–12 and graduate school were given passages to read at difficulty levels varying from D L = 2 to D L = 17, and relative difficulty varied from −8 to +10. A standardized reading test—the Accuracy Level Test—was used to estimate A l for each student, and two different readability techniques were used to estimate D l for each passage. The students were asked to decide what percent of each passage they comprehended after they had read it, and this judgement constituted an estimate of the accuracy of comprehension. The percent of passage comprehension was found to be a linear function of the relative difficulty of the material. The accuracy of comprehension can be predicted quite precisely from a mathematical equation given a knowledge of the level of difficulty of the material and the level of ability of the individual.
Leaf physiology and sugar concentrations of transplanted Quercus rubra seedlings in relation to nutrient and water availability

Newly planted seedlings incur transplant stress resulting from poor root-soil contact, which limits access to soil moisture and nutrients and reduces growth for one or more growing seasons. Controlled release fertilizer (CRF) applied at planting may reduce transplant stress by augmenting rhizosphere nutrient availability yet with potential risk of root system damage due to elevated fertilizer salt concentrations, which may be further exacerbated by drought. Under controlled conditions, we examined northern red oak (Quercus rubra L.) leaf physiological parameters and soluble sugar concentrations in response to varying nutrient levels (via CRF application) and moisture availability gradients ranging from drought to flooding. Net photosynthetic rates, transpiration rates, and chlorophyll fluorescence parameters responded positively to CRF application, and no interactions were observed between CRF and moisture availability; however, CRF did not increase soluble sugar concentrations. No effects of short-term drought were observed, but flooding exerted a rapid negative influence on net photosynthetic rates, transpiration rates, and chlorophyll fluorescence parameters; flooding also elevated soluble sugar concentrations, indicative of disrupted carbon partitioning and a much greater sensitivity to root-zone hypoxia than to drought in this species. Lack of interactions between CRF application and soil moisture availability indicates relatively similar responses of fertilized seedlings across moisture gradients.
On the Usefulness of Item Bias Analysis to Personality Psychology

A form of item bias known as Differential Item Functioning (DIF) occurs when two individuals with the same trait levels but different group membership do not have the same probability of endorsing an item in the keyed direction. The detection of DIF using Item Response Theory (IRT) arose in the cognitive testing domain, so the phenomenon is almost invariably perceived as undesirable. With the extension of IRT procedures to substantive areas of psychology, it is argued that DIF-prone items can afford valuable insights into the nature of the construct under study, especially where group differences are important. An example is presented using responses from 568 students completing a popular measure of Openness to Experience.
Reduced data projection slice image fusion using principal component analysis

In this paper we discuss the utilization of Principal Component Analysis, PCA, with projection slice synthetic discriminant function (PSDF) filters to reduce a data set that represents images from different sensor systems in order to extract relative information and features from the image set. The PCA helps to emphasize the differences in each of the training images in a given class. These differences are encoded into the PSDF filters. The PSDF filters provide a premise for data fusion by utilization of the projection-slice theorem. The PSDF is implemented with a few training images generated from the PCA, containing relevant information from all of the training images. The data in the principle components that are used to represent the entire data set can be emphasized by conditioning the eigen-values of the basis vectors used to corroborate important data packets in the entire data set. The method of data fusion, and preferred data emphasis in conjunction with the PST is discussed and the fused images are presented.
Passing the Baton: An Experimental Study of Shift Handover

Shift handovers occur in many safety-critical environments, including aviation maintenance, medicine, air traffic control, and mission control for space shuttle and space station operations. Shift handovers are associated with increased risk of communication failures and human error. In dynamic industries, errors and accidents occur disproportionately after shift handover. Typical shift handovers involve transferring information from an outgoing shift to an incoming shift via written logs, or in some cases, face-to-face briefings. The current study explores the possibility of improving written communication with the support modalities of audio and video recordings, as well as face-to-face briefings. Fifty participants participated in an experimental task which mimicked some of the critical challenges involved in transferring information between shifts in industrial settings. All three support modalities, face-to-face, video, and audio recordings, reduced task errors significantly over written communication alone. The support modality most preferred by participants was face-to-face communication; the least preferred was written communication alone.
Self-treatment of wounds by a capuchin monkey (Cebus apella)

A captive adult female capuchin monkey spontaneously manufactured and used tools to groom her vaginal area and four of her own wounds over a six-month period. The wounds apparently occurred during fights with other monkeys living in the same social groups. The monkey often groomed her vaginal area and wounds with tools she had coated with a sugar-based syrup. The monkey did not use tools to groom other body areas, nor did she use tools that were coated with substances other than syrup. This monkey’s unusual habit developed in the context of manufacturing and using tools in a feeding task. These observations demonstrate that the serendipitous performance of particular behaviours in appropriate contexts can lead to the discovery and practice of simple treatment of wounds by a monkey. The independent discovery of simple medicinal procedures in human cultures may have occurred in a similar manner. Such discoveries could have predated the development of sophisticated cultures in which medicinal practices were embedded and eventually recorded.
Self-Esteem in College Students with a Childhood History of Attention Deficit Hyperactivity Disorder

Abstract Differences in self-esteem between college students who indicated a childhood history of Attention Deficit Hyperactivity Disorder (ADHD) and college students in general were examined. Factors predictive of self-esteem among those college students who identified themselves as ADHD in childhood were also studied. Significant differences in self-esteem were found between the college students self-identified as ADHD and the general college population even when gender, SES, and aptitude test scores were taken into account. Self-esteem in college students who self-identified as ADHD was positively correlated with greater social skills and negatively correlated with current symptoms. Implications of these results are discussed.
Parameter Estimation with Cumu lative Errors

Estimation of parameters is considered for several cases involving correlated errors. The cases include first and second order cumulative errors and a more general first order case. Estimators for first order cumulative errors are tabulated for five simple linear models. More general estimators for linear models are given in matrix form and it is demonstrated using maximum likelihood that many cases can be written simply in the form of differences. Expressions are also given that can be used to estimate the correlation coefficient and the error variance. Two examples are given to illustrate the new results.
Venous Thrombosis in the Nephrotic Syndrome

Thrombosis complicates the nephrotic syndrome in about 25% of cases, an association that was first noted in the 19th century. More recent work has defined the pathophysiologic basis for this association.
Transition From Residency to Practice: Life Does Get Better!

Themulti-institutional studybyGifford et al1 in this issue reports the results of a survey of 371 residents in 13 general surgeryprogramsandexploreshowmanyresidents consider leaving residency and why. The authors correlate their findingswith data obtained from theprogramdirectorsof these residencies. They found that 58.0%seriously consideredquitting, mostly during years 1 and 2 and research years, but that ahigherpercentageofwomenconsider quitting thanmenand thatmorewomenactuallydoquit in theseprograms thanmen. Residents thinkaboutquittingwhenthey feel excessively sleep deprived on a specific rotation or because they feel that general surgeryhasanundesirable future lifestyle.Thosewhoconsiderquittingbutdonotdosoremain inresidencybecause they switch to adifferent rotationwhere theybecomebetter rested orbecause theyreceivesupport fromfamily,a significantother, or other residents. Although traditionalist old-school surgeons may still argue that making residency too soft will fail to prepare residents for the hard reality of surgical practice, this study offers a strong argument for programs to examine each of their rotations and take steps to improve the work hours of brutal rotations to create amore positive learning environment. It is difficult for anyone todoone’s best for their patients or beable to concentrate on learning when all you can think of is how tiredyouare. Correcting adeviant rotationor two ismuch less difficult than addressing the misperception surgeons themselves have created that one cannot have a balanced life and still practice surgery and that burnout, depression, and substance abuse are rampant among surgeons in practice. A look around all of our surgical communities should be enough to dispel thatmyth. Young surgeons seek and findpracticeswith structured hours and call. The starting salary of general surgeons is higher than ever and is competitivewith that of other procedural specialties. Millennials and Generation Xers decline the martyr or victim role and take control of their lives toa fargreaterextent thanpreviousgenerations.Themyth that surgeons are inevitably downtrodden, abused victims with lousy lives should be dispelled. Program directors must take a purposeful, proactive approach from the beginning of surgery residency that shows residents how they can achieve a healthy balance of work and life, create practices over which they have control, and live happy, productive lives. We have failed our younger generation if we whine and complain about our wretched lives rather than taking the steps that are available to us to be proactive, take control of our own fates, and realize what a privileged position we are in as surgeons. Women residents are particularly vulnerable to worries that they may not be able to juggle competing demands of their families and their careers2 and need to be matched with female surgeons in practice who have managed successfully to find that balance.
2D electronics: Graphene and beyond

In this paper, we review the essential physics that lead to the most impressive properties of two-dimensional (2D) nanocrystals, primarily graphene and transition-metal dichalcogenides (TMD). We also highlight some applications uniquely enabled by these 2D materials in the nanoelectronics domain and discuss the related challenges and opportunities.
Effect of recombinant human interferon-alpha2b on receptors for steroid hormones and epidermal growth factor in patients with endometrial cancer

Interferons (IFNs) may modulate oestrogen (ER), progesterone (PR) and epidermal growth factor (EGFR) receptor expression in vitro. ER, PR and EGFR levels in tumour specimens taken from 13 patients with endometrial adenocarcinomas before and after 5 days' intramuscular treatment with 5 x 10(6) U per recombinant human leucocyte interferon-alpha 2b (rh IFN-alpha 2b). After treatment, ER (P less than 0.01) and PR (P less than 0.05) levels were significantly increased with a simultaneous reduction of EGFR content (P less than 0.05). Since the expression of ER and PR characterises more differentiated hormono-sensitive tumours, while EGFR are preferentially expressed in less differentiated tumours, the increase of steroid hormone receptor levels with the reduction of EGFR expression suggests that rh IFN-alpha 2b may induce endometrial cancer cell differentiation. Moreover, the decrease of EGFR levels may explain the antiproliferative effect of IFNs.
A millennium of obstetrics and gynaecology.

The evolution of obstetrics and gynecology started when Eucharius Rosslin first printed the book The Rose Garden of the Pregnant Womens Nurse in 1513 which deals exclusively with obstetrics. Many found the book informative leading to numerous editions and translations including the first English edition "The Byrth of Mankynde" (London 1540). Aside from Rosslin Jacob Rueff also created a book providing instructions to midwives. His book also provides a description of forceps and to extract a dead fetus and cephalic version. Beginning the 17th century several celebrated midwives published several books on the subject and led to the development of anatomy as a science. Within the succeeding two centuries many anatomists made further contributions to the field of obstetrics providing a detailed description of the reproductive system. In the 19th century the development was focused on the recognition of the etiology of puerperal fever the discovery of anesthesia and the invention of pelvic surgery. The early part of the 20th century saw the usefulness of radiography and radium as a treatment for cancer of the uterine cervix. The rise of hospitals and clinics for the diseases of women and the promulgation of the need for antenatal obstetrical care was observed during this period. By the 1920s and 1930s the hormone estrogen and progesterone were isolated which further led to enormous advances in endocrinology infertility and reproductive sciences.
Popular to Proficient: Cultivating a Contextual Appreciation of Dance on a Rural Historically Black College Campus

This article explores issues involved in building a degree program in dance at a historically black university (HBCU) in the Southern United States. It discusses the influence of popular dance in a...
Why Change Gaits? Recruitment of Muscles and Muscle Fibers as a Function of Speed and Gait

Muscles shorten, stay the same length and are stretched while they are active during normal modes of terrestrial locomotion. The relative importance of these different types of muscular activity changes as animals change gait. Energy is conserved during a walk by an alternate storage and recovery of gravitational potential energy within each stride, as in an inverted pendulum. In order for this transfer of energy to take place, muscular activity is required to hold the limb rigid while the animal rotates over it. Energy is conserved by a spring mechanism during running, trotting, galloping, and hopping. Energy is stored when active muscles and their tendons are stretched and recovered as they subsequently shorten. The recruitment patterns of motor units as a function of speed therefore, depends on the type of muscular activity as well as the force exerted. Discontinuities in the cross sectional area of active fibers with increasing speed have been observed at the trot-gallop transition. It is suggested that at this point the trunk is recruited as an additional spring enabling more energy to be stored elastically. It is concluded that we must consider what muscles are doing during normal modes of locomotion before we become too involved in designing schemes of motor unit recruitment.
Generalized contact geometry and T-duality

Abstract We study generalized almost contact structures on odd-dimensional manifolds. We introduce a notion of integrability and show that the class of these structures is closed under symmetries of the Courant–Dorfman bracket, including T-duality. We define a notion of geometric type for generalized almost contact structures, and study its behavior under T-duality.
Clonogenic haematopoietic progenitor assays from clinically normal horses

Clonal assays for haematopoietic progenitors were performed on mononuclear cells isolated from bone marrow samples collected from the sternebrae of normal horses. Colony-forming units-erythroid (CFUE), burst-forming units-erythroid (BFU-E), colony-forming units-granulocyte/monocyte (CFU-GM) and colony-forming units-fibroblastic (CFU-F) were assayed, and reference values for clinically normal horses were established. The mean numbers of CFU-E, BFU-E and CFU-GM per 5 × 104 cells were 329 ± 48, 30 ± 5 and 131 ± 13, respective. The mean number of CFU-F was 49 ± 6 per 2 ± 10 cells. The numbers of CFU-E and BFU-E were linearly related to the concentrations of fetal bovine serum (FBS), bovine serum albumin (BSA) and the cell number plated. The number of CFU-E were increased in the presence of erythropoietin (EPO) but its presence was not required for colony growth. BFU-E had an absolute requirement for EPO but the number of BFU-E was not linearly related to dose of EPO. Methods for clonal assays of equine hematopoietic progenitors are described.
A preliminary study of ion implanted diffusion barriers in high temperature metal matrix composites

Etude de la diffusion dans les couples W/Ni avec ou sans barriere de diffusion obtenue par implantations d'ions calcium, sodium, baryum. Les couples de diffusion sont recuits a 1500 K pendant 50 heures. Cette etude est un travail preliminaire concernant le controle de l'interdiffusion fibre-matrice dans les materiaux composites
Amplitude demodulation of filtered AM/PM signals

The input signal is assumed to be simultaneously amplitude and phase modulated (AM and PM), and the bandpass filter may be unsymmetrical and mistuned. The demodulator output is the magnitude of the filtered signal for an AM receiver or its phase for a PM receiver. For such a system with amplitude demodulation, the results are found and presented in the form of an expansion in which the leading term is the linear (i.e., undistorted) reproduction of the input AM and the successive terms represent the distortion and crossmodulation. The significant effects are given by the first few terms of the expansion because the applications of interest are those in which the distortion is small. A spectral analysis is performed on the output of an AM receiver. The leading DC, linear, and nonlinear terms of the output power spectrum are derived by assuming that the amplitude- and phase-modulating signals are uncorrelated zero-mean random Gaussian processes. >