bluuebunny/crossref_metadata_2025 huggingface dataset:
Wave Propagation in a Random Medium With Stratified
Authors: Liu C. H.
Published: November 2015

We study the propagation of a wave in an arbitrarily stratified medium in the presence of small random irregularities. The technique of two‐dimensional Fourier‐Stieltjes spectral representation for the random field is used to formulate this problem. With high frequency wave propagation in mind, we applied the W.K.B. method to yield approximate expressions for structure (correlation) functions for the logarithmic amplitude and phase departure of the wave field. The results are compared with those derived for a random medium with homogeneous background. An example is given in which the effect on the amplitude and phase fluctuations due to the stratified background is explicitly computed.
Admittance of Infinite and Finite Cylindrical Metallic
Authors: Andersen J. Bach
Published: November 2015

A monopole antenna excited by a coaxial line is studied in detail. The mathematical model of the excitation is a magnetic ring current the radius of which may be larger than the radius of the cylinder. First a study is made of the waves guided by and radiated from an infinite cylinder. Numerical results for the current and the conductance are given. The conductance decreases when the gap width increases.

The standing‐wave antenna is treated with an assumed effective gap at the antenna ends. A solution of the antenna problem is found by superimposing the multiply reflected waves. In the solution, the effect of the gap and the antenna end separates. Accurate values for the gap admittance and the end admittance are derived from experimental values obtained by Hartig.
Influence of a Radial Magnetic Field on the Resonances of a Spherical Plasma Cavity
Authors: Large David B. , Wait James R.
Published: November 2015

A method is described for calculating the resonance characteristics of the earth‐ionosphere cavity. Particular attention is paid to the influence of the geomagnetic field which, for purposes of the analysis, is assumed to be purely radial. In the model used, the ionosphere is represented as a homogeneous concentric shell, which is regarded as a cold electron plasma with collisions. It is found that the geomagnetic field lowers the real resonance frequencies from those for the corresponding isotropic model.
A Suggested Conjugate Point Dependence for Intense Temperate Latitude Sporadic E
Authors: Smith Ernest K.
Published: November 2015

Certain statistical features of the occurrence of intense sporadic E(Es) at temperate latitudes continue to defy explanation. These are: The dominance of the summer maximum, the double‐humped diurnal curve, the abrupt collapse of the summer peak as one progresses to higher latitudes than 60° geomagnetic, and the preference for quiet over magnetically disturbed days. The location of the plasmapause is found to he appropriate to explain the collapse of the summer peak; and its variation in position a possible reason for the preference for quiet days. The summer peak itself (and possibly the shape of the diurnal curve) may he attributable to conditions in the conjugate ionosphere.
Measurement and Intensity of Energetic Electrons at the Equator at 6.6 Re
Authors: Lezniak T. W. , Arnoldy R. L. , Parks G. K. , Winckler J. R.
Published: November 2015

This paper presents preliminary results of measurements of 50 to 1000 keV electrons at the geomagnetic equator at 6.6 Re. Quiet‐day electron fluxes exhibit a diurnal dip in intensity at local midnight accompanied by a softening of the electron spectrum. During geomagnetically disturbed times the 50 to 150 keV electrons exhibit large fluctuations in intensity; we have denoted these fluctuations as “spikes.” These spikes are largest just after local midnight and decrease in intensity as local time increases. They have a duration of about 1 hr and tend to recur with about a 2‐hr period. The electron spectrum softens considerably during the spikes. Generally the variations in intensity of the electrons correlates excellently with the Kp index.
Rapid Geomagnetic Field Variations Observed at Conjugate Locations
Authors: Campbell Wallace H.
Published: November 2015

In the frequency range of 4.0 to 0.002 Hz natural rapid variations of the magnetic field of the earth have been reported to occur at pairs of near‐geomagnetically conjugate locations in the Northern and Southern Hemispheres. This paper is a review of the present knowledge of such phenomena. At conjugate auroral and subauroral latitude stations, the pulsations of irregular amplitude variation (pi) which are associated with particle precipitation, are, at times, simultaneous and of identical form, but on occasions quite dissimilar activity occurs. The pulsations with a smooth, more sinusoidal form (pc) are generally quite similar at conjugate locations. Polarization determinations of the pc's have been most recently investigated to determine the propagation characteristics of hydromagnetic waves in the magnetosphere. Similar rapid magnetic field variations at low latitude and equatorial stations are often found at many widely spaced stations not necessarily conjugate.
The Role of the Main Geomagnetic Field in Locating Conjugate Points
Authors: Cain Joseph C.
Published: November 2015

A sample distribution of conjugate points is calculated from various models of the main geomagnetic field, evaluated at different epochs. A summary of the conclusions is: (1) For L < 4 the errors are of the order of a few tens of kilometers; (2) older models of the field such as the Finch‐Leaton give results within a few degrees of the latest more accurate models; (3) use of the eccentric dipole approximation gives errors that range from a few tens of kilometers at high latitude to several hundred kilometers near the equator; and (4) the secular change of conjugate‐point locations is very small, averaging 1 to 10 km/yr. Inclusion of Mead's boundary field for a trace from Macquarie Island to Alaska (L = S) shifts the conjugate only about 100 km. It is concluded that for L ⩾ 5 the field line passes through regions where the field intensity is weak enough to require that realistic estimates of the distortions due to plasma interactions be included in conjugate‐point determinations. (These estimates are not now available.)
Conjugate Optical Measurements — Total Night Hours Possible for One Year
Authors: Marovich E.
Published: November 2015

Results are presented of calculations leading to maps of the Northern and Southern Hemispheres that show contours, per annum, of the number of simultaneous nighttime hours at magnetically conjugate observatories.
Radiation From a Horizontal Electric Dipole Buried in a Multilayer Earth
Authors: Biggs Albert W.
Published: November 2015

Field expressions for a horizontal electric dipole buried in a three‐layer earth are derived with techniques developed for a two‐layer earth. Parameters include the radio frequency, upper‐ and lower‐ layer depths, and the relative dielectric constant and conductivity or loss tangent of each layer. Analogies between multisection transmission lines and multilayer earth are discussed.
Radar Interferometry Measurements of a Turbulent Plasma
Authors: Weissman D. E. , Guthart H. , Morita T.
Published: November 2015

A laboratory experiment has been conducted that demonstrates the applicability of radar interferometry to the measurement of the width of a turbulent plasma column. This is done by inferring the spatial distribution of the incoherent electromagnetic power backscattered from the column. The measurements of the spatial correlation of the backscattered electromagnetic fields are in good agreement with a function derived theoretically by using extensive diagnostic data.
Antenna Radiation Properties in Presence of Anisotropic Plasmas
Authors: Bachynski M.P. , Gibbs B. W.
Published: November 2015

An extensive quantitative experimental investigation was conducted on the influence of a magnetic field on the radiation from a horn antenna situated behind a layer or sheath of plasma. The magnetic field direction in the experiments was along the principal direction of radiation of the antenna which is normal to the layer of plasma.

The experimental results were compared with theory based on the reciprocity theorem. For the left circularly polarized wave radiation pattern, propagation effects at off‐normal incidence corresponding to the condition for which the ordinary wave mode switches to the extraordinary wave mode as the electron density passes through the critical density are shown to be of importance. For the right circularly polarized wave mode, significant departures in the measured radiation pattern from the theoretical occur in the region of the electron cyclotron frequency and below. Satisfactory correspondence between theory and experiment is found for values of the electron cyclotron frequency that are greater than the wave frequency.
Ionospheric Focusing for an Antenna in the Presence of the Geomagnetic Field
Authors: Walsh D. , Weil Herschel
Published: November 2015

A geometrical optics treatment of ionospheric focusing is presented which is exact within the assumptions of horizontal stratification of the ionosphere and of the collision‐free Appleton‐Hartree equation. In addition to effects of ray refraction, the expression derived for gain distribution in the beam outside the ionosphere includes in a natural manner the directional characteristics of the antenna in the plasma. These involve both the antenna geometry and the characteristic polarizations of the incident waves. The factors in the gain expression which are dependent only on the plasma characteristics are expressed in closed form. Evaluation of the remaining factors, in general, requires knowledge of the current distribution on the antenna. For the case of an electrically short dipole, this evaluation is carried out and the gain distribution expressed in closed form, apart from a normalizing factor that can only be determined by numerical integration. The properties of the gain distribution are illustrated by contour plots.
Is waveform worth it? A comparison of LiDAR approaches for vegetation and landscape characterization
Authors: Anderson Karen , Hancock Steven , Disney Mathias , Gaston Kevin J.
Published: November 2015

Light Detection and Ranging (LiDAR) systems are frequently used in ecological studies to measure vegetation canopy structure. Waveform LiDAR systems offer new capabilities for vegetation modelling by measuring the time‐varying signal of the laser pulse as it illuminates different elements of the canopy, providing an opportunity to describe the 3D structure of vegetation canopies more fully. This article provides a comparison between waveform airborne laser scanning (ALS) data and discrete return ALS data, using terrestrial laser scanning (TLS) data as an independent validation. With reference to two urban landscape typologies, we demonstrate that discrete return ALS data provided more biased and less consistent measurements of woodland canopy height (in a 100% tree covered plot, height underestimation bias = 0.82 m; sd = 1.78 m) than waveform ALS data (height overestimation bias = −0.65 m; sd = 1.45 m). The same biases were found in suburban data (in a plot consisting of 100% hard targets e.g. roads and pavements), but discrete return ALS were more consistent here than waveform data (sd = 0.57 m compared to waveform sd = 0.76 m). Discrete return ALS data performed poorly in describing the canopy understorey, compared to waveform data. Our results also highlighted errors in discrete return ALS intensity, which were not present with waveform data. Waveform ALS data therefore offer an improved method for measuring the three‐dimensional structure of vegetation systems, but carry a higher data processing cost. New toolkits for analysing waveform data will expedite future analysis and allow ecologists to exploit the information content of waveform LiDAR.
Dose‐Dependent Therapeutic Distinction between Active and Passive Targeting Revealed Using Transferrin‐Coated PGMA Nanoparticles
Authors: Singh Ruhani , Norret Marck , House Michael J. , Galabura Yuriy , Bradshaw Michael , Ho Diwei , Woodward Robert C. , Pierre Timothy G. St. , Luzinov Igor , Smith Nicole M. , Lim Lee Yong , Iyer Killugudi Swaminathan
Published: November 2015

The paradigm of using nanoparticle‐based formulations for drug delivery relies on their enhanced passive accumulation in the tumor interstitium. Nanoparticles with active targeting capabilities attempt to further enhance specific delivery of drugs to the tumors via interaction with overexpressed cellular receptors. Consequently, it is widely accepted that drug delivery using actively targeted nanoparticles maximizes the therapeutic benefit and minimizes the off‐target effects. However, the process of nanoparticle mediated active targeting initially relies on their passive accumulation in tumors. In this article, it is demonstrated that these two tumor‐targeted drug delivery mechanisms are interrelated and dosage dependent. It is reported that at lower doses, actively targeted nanoparticles have distinctly higher efficacy in tumor inhibition than their passively targeted counterparts. However, the enhanced permeability and retention effect of the tumor tissue becomes the dominant factor influencing the efficacy of both passively and actively targeted nanoparticles when they are administered at higher doses. Importantly, it is demonstrated that dosage is a pivotal parameter that needs to be taken into account in the assessment of nanoparticle mediated targeted drug delivery.
Priority Monism Is Contingent
Authors: Siegel Max ,   Philosophy Documentation Center
Published: November 2015

This paper raises a challenge to Jonathan Schaffer’s priority monism. I contend that monism may be true at the actual world but fail to hold as a matter of metaphysical necessity, contrary to Schaffer’s view that monism, if true, is necessarily true. My argument challenges Schaffer for his reliance on contingent physical truths in an argument for a metaphysically necessary conclusion. A counterexample in which the actual laws of physics hold but the physical history of the universe is different shows that priority monism is contingently true at best. I suggest some general lessons for discussion of metaphysical dependence.
Effect of Chelate Ring Size in Iron(II) Isothiocyanato Complexes with Tetradentate Tripyridyl‐alkylamine Ligands on Spin Crossover Properties
Authors: Leibold Michael , Kisslinger Sandra , Heinemann Frank W. , Hampel Frank , Ichiyanagi Yuko , Klein Michael , Homenya Patrick , Renz Franz , Toftlund Hans , Brehm Georg , Schneider Siegfried , Reiher Markus , Schindler Siegfried
Published: November 2015

Iron(II) complexes of the type [Fe(L)(NCS)2] with tetradentate ligands L are well known to show spin crossover properties. However, this behavior is quite sensitive in regard to small changes of the ligand system. Starting from the thoroughly investigated complex [Fe(tmpa)(NCS)2] [tmpa = tris(2‐pyridylmethyl)amine, also abbreviated as tpa in the literature] we modified the ligand by increasing systematically the chelate ring sizes from 5 to 6 thus obtaining complexes [Fe(pmea)(NCS)2], [Fe(pmap)(NCS)2], and [Fe(tepa)(NCS)2] [pmea = N,N‐bis[(2‐pyridyl)methyl]‐2‐(2‐pyridyl)ethylamine, pmap = N,N‐bis[2‐(2‐pyridyl)ethyl]‐(2‐pyridyl)methylamine, and tepa = tris[2‐(2‐pyridyl)ethyl]amine]. All complexes were structurally characterized and spin crossover properties were investigated using Mößbauer spectroscopy, magnetic measurements, and IR/Raman analyses. The results demonstrated that only the iron complexes with tmpa and pmea showed spin crossover properties, whereas the complexes with the ligands pmap and tepa only formed high spin complexes. Furthermore, DFT calculations supported these findings demonstrating again the strong influence of ligand environment. Herein the effect of increasing the chelate ring sizes in iron(II) isothiocyanato complexes with tetradentate tripyridyl‐alkylamine ligands is clearly demonstrated.
A Really Bad Deal: The Iran Nuclear Deal and Its Implications
Authors: Norell Magnus
Published: November 2015

With the Joint Comprehensive Plan of Action Iran has been handed an important diplomatic victory. As a result, Iran can keep its nuclear infrastructure, something which the negotiators for the P5+1–-the five permanent members of the UN Security Council (the US, the UK, France, Russia and China) plus Germany–-said from the outset should be dismantled. It has also let Iran off the hook of having to come clean about its constant cheating over the years concerning its nuclear agenda. And in the short run, a far more important outcome of the deal is that Iran will be able to free up billions of dollars to continue its regional agenda of influencing and destabilising countries in the Middle East.
Beyond Economics: The Geopolitical Importance of the Transatlantic Trade and Investment Partnership
Authors: Pavlova Pavlina
Published: November 2015

With the Transatlantic Trade and Investment Partnership, Europe has a decisive opportunity to define the direction of future global trade. However, concluding the biggest agreement of its kind seems to be trying the internal unity of the Union. A wave of protests has swept across Europe as many fear the hidden costs behind regulatory cooperation with our neighbours across the Atlantic. Getting sceptics on board will require more than economic reasoning. The hidden value of the free trade agreement is its geopolitical importance and the historic opportunity it offers for the West. Sealing the deal with the US would strengthen Euro-Atlantic cooperation, counter the influence of China, diminish European dependency on Russia's energy imports and promote the Western economic model. Should the negotiations fail, mutual blame and internal frustration will isolate the EU.
Guidelines: the do’s, don’ts and don’t knows of feedback for clinical education
Authors: Lefroy Janet , Watling Chris , Teunissen Pim W. , Brand Paul
Published: November 2015

Introduction The guidelines offered in this paper aim to amalgamate the literature on formative feedback into practical Do’s, Don’ts and Don’t Knows for individual clinical supervisors and for the institutions that support clinical learning.

Methods The authors built consensus by an iterative process. Do’s and Don’ts were proposed based on authors’ individual teaching experience and awareness of the literature, and the amalgamated set of guidelines were then refined by all authors and the evidence was summarized for each guideline. Don’t Knows were identified as being important questions to this international group of educators which if answered would change practice. The criteria for inclusion of evidence for these guidelines were not those of a systematic review, so indicators of strength of these recommendations were developed which combine the evidence with the authors’ consensus.

Results A set of 32 Do and Don’t guidelines with the important Don’t Knows was compiled along with a summary of the evidence for each. These are divided into guidelines for the individual clinical supervisor giving feedback to their trainee (recommendations about both the process and the content of feedback) and guidelines for the learning culture (what elements of learning culture support the exchange of meaningful feedback, and what elements constrain it?)

Conclusion Feedback is not easy to get right, but it is essential to learning in medicine, and there is a wealth of evidence supporting the Do’s and warning against the Don’ts. Further research into the critical Don’t Knows of feedback is required.
Heterotopic Pregnancy with an Intrauterine Twin Gestation and Ruptured Tubal Pregnancy: An Unusual Presentation
Authors: Bagchi Sipra , Aggarwal Abhinav , Gupta Ashish Kumar , Aggarwal Aakriti Kapoor , Sachdeva Primal , Pandit Abhinav
Published: November 2015

Heterotopic pregnancy is diagnosed as coexistent presence of fetuses at two or more implantation sites. Its incidence is very rare with presence of live intrauterine twins being even rarer. Diagnosis in such cases is difficult with ultrasound being the investigation of choice. Management is primarily surgical. It is a clinical entity which is becoming even more common with widespread use of assisted reproductive techniques. A 20-year-old primigravida with 10 weeks of gestation presented with sudden onset pain on right side of abdomen. She had history of treatment for infertility for 1 year.
Ultrasound revealed live intrauterine twin pregnancy with a heterogeneous lesion in right adnexal region and peritoneal free fluid. In concordance with clinical findings a diagnosis of heterotopic pregnancy with ruptured ectopic was made. Patient was managed through emergency laparotomy without disturbing the intrauterine twin gestation. Higher incidence of heterotopic pregnancy has been observed in patients undergoing assisted reproductive techniques and therefore warrant regular and detailed examination and follow up to avoid complications like ruptured ectopic pregnancy.
Functional Outcomes of Burn Patients with or without Rehabilitation in Mainland China
Authors: Tang Dan , Li-Tsang Cecilia W.P. , Au Ricky K.C. , Li Kui-cheng , Yi Xian-feng , Liao Lin-rong , Cao Hai-yan , Feng Ya-nan , Liu Chuan-shun
Published: November 2015

Background/Objective

To evaluate the functional outcomes of moderate to severe burn patients with and without rehabilitation in terms of self-care performance and quality of life (QOL).

Methods

Fifty-five patients with total burn surface area of 30% or more were divided into two groups: rehabilitation and conventional care groups. The rehabilitation group underwent comprehensive rehabilitation interventions (e.g., occupational therapy, physiotherapy, and patient and family education) in addition to standard clinical interventions received by the conventional care group. The outcomes included self-care performance (Modified Barthel Index [MBI]), QOL (World Health Organization Quality of Life-BREF), pain and itchiness (Visual Analogue Scale [VAS]), quality of sleep, and mental health (Self-Rating Depression Scale [SDS] and Self-Rating Anxiety Scale) measured before and 3 months after the intervention.

Results

After the intervention, significant improvements were found in MBI, all dimensions of QOL, pain, and SDS in the rehabilitation group (all p < .05). In the conventional care group, significant improvements were found only in MBI (p < .001), the physical health dimension of QOL (p < .01), and pain (p < .001). Group comparisons showed that the rehabilitation group achieved significantly better outcomes after the intervention in MBI (p < .001), VAS score of itching (p = .009), and the physical health (p = .002), psychological health (p = .021), and social relationships dimensions of QOL (p < .001).

Conclusion

Patients with moderate to severe burn injuries can benefit from rehabilitation interventions in terms of physical health, mental health, performance of daily living, and QOL.
Comparison of treatment outcomes of endoscope‐guided pneumatic dilation and laparoscopic Heller myotomy
Authors: Wang Hsin‐Ming , Tai Wei‐Chen , Chuah Seng‐Kee , Lu Hung‐I , Lu Lung‐Sheng , Liang Chih‐Ming , Kuo Chung‐Huang , Chiu Yi‐Chun , Wu Keng‐Liang , Changchien Chi‐Sin
Published: November 2015

The debate on which is the better choice between laparoscopic Heller myotomy (LHM) and endoscopic pneumatic dilation (PD) for esophageal achalasia has been ongoing for decades. This study aims to compare the results of endoscope‐guided PD and LHM in 42 patients with achalasia between May 1996 and August 2011. Twenty‐one patients who had received PD and 21 who had received LHM were enrolled. The cumulative remission rate was analyzed using the Kaplan–Meier method with the assessment of symptom scores between grades before and after PD or LHM done at 6 weeks, 6 months, 1 year, and then every year thereafter. Possible confounding factors related to the remissions were analyzed by Cox's proportional hazard model. For PD, the cumulative remission rates were 81.0% (1 year), 76.2% (2), 66.7% (3), 61.9% (4), and 47.6% (5). For LHM, the cumulative remission rates were 90.5% every year from the 1st to the 5th. The LHM patients had significantly better remission rates than the PD patients (p = 0.033, by log‐rank test). The LHM group had a longer hospital stay than the PD group [median (interquartile range): 8 (6.5–10) days vs. 3 (2–3) days, p < 0.001) and had more reflux complications (52.4% vs. 19.0%, p = 0.024). No perforation occurred in either group. In conclusion, the 5‐year cumulative effectiveness of LHM is better than that of PD despite the association of LHM with more reflux events (52.4%).
Granitoids of the Gamov intrusion (southern Primorye), its peculiarities and indicative and geodynamic role
Authors: Kruk N.N. , Golozubov V.V. , Kasatkin S.A. , Rudnev S.N. , Vrzhosek A.A. , Kuibida M.L. , Vovna G.M.
Published: November 2015

We studied the geologic position, mineralogy, petrography, chemical composition, and age of granitoids of the Gamov batholith located in the Heilongjiang-Grodekovo terrane, southern Primorye (Russia). The studies have revealed four intrusive rock phases, from gabbro to leucogranites, in the massif. U–Pb zircon dating of tonalites of phase II and leucogranites of phase IV (254 ± 4 and 259 ± 2 Ma, respectively) shows that the intrusion of granitoids took place in the Late Permian without a significant gap in time. Structural investigations gave evidence for the intrusion in the E–W compression setting. Geochemical studies have revealed granitoids of strongly different compositional types in the intrusive massif: gabbroids, quartz diorites and tonalites with characteristics of low-alumina TTG, calc-alkalic granodiorites and I-type granites, and moderately alkaline leucogranites. The obtained data, together with the results of previous research into the Permo-Triassic granitoids of southern Primorye, reject their formation as a result of the evolution of the Solonker oceanic structures and suggest a more intricate tectonic scenario, which calls for additional study.
Liquid immiscibility during crystallization of forsterite–phlogopite ijolites at Oldoinyo Lengai Volcano, Tanzania: study of melt inclusions
Authors: Sekisova V.S. , Sharygin V.V. , Zaitsev A.N. , Strekopytov S.
Published: November 2015

The paper is concerned with study of melt inclusions in minerals of ijolite xenoliths at Oldoinyo Lengai Volcano. Melt inclusions with different phase compositions occur in forsterite macrocrysts and in diopside, nepheline, fluorapatite, Ti-andradite, and Ti-magnetite crystals. Nepheline contains primary melt inclusions (silicate glass + gas-carbonate globule ± submicron globules ± sulfide globule ± daughter/trapped phases, represented by diopside, fluorapatite, Ti-andradite, and alumoåkermanite). The gas-carbonate globule consists of a gas bubble surrounded by a fine-grained aggregate of Na–Ca-carbonates (nyerereite and gregoryite). Fluorapatite contains primary carbonate-rich melt inclusions in the core, which consist of nyerereite, gregoryite, thenardite, witherite, fluorite, villiaumite, and other phases. Their mineral composition is similar to natrocarbonatites. Primary melt inclusions (glass + gas bubble ± daughter phases) are rare in diopside and Ti-andradite. Diopside and forsterite have trails of secondary carbonate-rich inclusions. Besides the above minerals, these inclusions contain halite, sylvite, neighborite, Na–Ca-phosphate, alkali sulfates, and other rare phases. In addition, diopside contains sulfide inclusions (pyrrhotite ± chalcopyrite ± djerfisherite ± galena ± pentlandite). The chemical compositions of silicate glasses in the melt inclusions vary widely. The glasses are characterized by high Na, K, and Fe contents and low Al contents. They have high total alkali contents (16–23 wt.% Na2O + K2O) and peralkalinity index [(Na + K)/Al] ranging from 1.1 to 7.6. The carbonate-rich inclusions in the ijolite minerals are enriched in Na, P, S, and Cl. The data obtained indicate that the parental melt in the intermediate chamber was heterogeneous and contained silicate, natrocarbonate, and sulfide components during the ijolite crystallization. According to heating experiments with melt inclusions, silicate–carbonate liquid immiscibility occurred at temperature over 580 °C.
Evaluación del tutor en la aplicación de la estrategia de aprendizaje basado en problemas en las asignaturas de Integración Básico Clínica I y II
Authors: Morales-López Sara , Muñoz-Comonfort Armando , Fortoul-van der Goes Teresa I.
Published: November 2015

Introducción: El ABP es una de las estrategias más empleadas en la educación médica y tienen sus inicios en la Universidad de McMaster en 1969. La figura del tutor-facilitador es relevante ya que es el que guía al pequeño grupo durante el proceso.
Objetivo: Evaluar por parte de los estudiantes al tutor de las asignaturas de Integración Básico Clínica I y II con la aplicación del cuestionario de 24 ítems propuesto por Martínez-González et al.
Método: Estudio descriptivo, retrospectivo y transversal. Se aplicó el cuestionario de 25 ítems con escala tipo Likert de cinco opciones, a los estudiantes de las obligatorias de IBC-I e IBC-II después de haber trabajado con sus tutores durante todo el curso. Se evaluaron cuatro ciclos escolares de IBC-I y tres de IBC-II. Se determinaron las frecuencias de respuesta, la media, el error estándar, análisis de varianza y se calculó la confiabilidad ( α de Cronbach) del cuestionario en cada aplicación.
Resultados: Se aplicaron 6,862 cuestionarios que incluyeron el 83% de la población en cada ciclo escolar. Los valores de confiabilidad fueron de 0.9 en cada evaluación. Las respuestas con valores más bajos se observaron en «la participación del tutor como guía», y «no favorecer la participación de los integrantes del grupo» es un problema recurrente.
Conclusiones: El ABP es la estrategia de las asignaturas evaluadas y la función del tutor es la base del éxito para el buen funcionamiento del trabajo en pequeños grupos. Los datos llevan a la reflexión sobre la necesidad de modificaciones en los talleres y en la forma de interactuar con los tutores para reforzar sus funciones en la estrategia del ABP.
Periodic saltation over hydrodynamically rough beds: aeolian to aquatic
Authors: Berzi Diego , Jenkins James T. , Valance Alexandre
Published: November 2015

We determine approximate analytical solutions for average periodic trajectories of particles that are accelerated by the turbulent shearing of a fluid between collisions with a hydrodynamically rough bed. We indicate how the viscosity of the fluid may influence the collisions with the bed. The approximate solutions compare well with periodic solutions for average periodic trajectories over rigid bumpy and erodible beds that are generated numerically. The analytic solutions permit the determination of the relations between the particle flux and the strength of the shearing flow over a range of particle and fluid properties that vary between those for sand in air and sand in water.
Fishing in Port Jackson, New South Wales–more than met the eye
Authors: Steele Dominic
Published: November 2015

Contemporary diaries and the water-colours of artists such as the Port Jackson Painter vividly tell of Aboriginal life when the First Fleet in 1788 settled its cargo of convicts in Australia. Fishing was important around the waters of Port Jackson, whose Aboriginal inhabitants are recorded to have used the techniques of spear-fishing and angling. Were other methods also used? Fish remains from a shell midden provide an opportunity to investigate.
Our own engendered species
Authors: Hurcombe Linda
Published: November 2015

The study of gender in ancient societies seems inseparable from the place of gender in our own society–and therefore inseparable from the particular attitudes and expectations those contemporary manners create. This BIG problem is explored, and some approaches to its resolution are developed.
Zhukaigou, steppe culture and the rise of Chinese civilization
Authors: Linduff Katheryn M.
Published: November 2015

Zhukaigou, a late prehistoric site in Inner Mongolia, stands in an important zone, the region where the steppe cultures meet the settled farming civilization of China. As elsewhere across the Asian steppes, that zone where each tradition meets its other is observed both from its archaeology and from such clues as we have to ancient perceptions of significant others.
The working of pigment during the Aurignacian period: evidence from Üçagizli cave (Turkey)
Authors: Minzoni-Déroche Angela , Menu Michel , Walter Philippe
Published: November 2015

New finds from the Upper Palaeolithic of Anatolia, and the mineralogical analysis of their colours, extends evidence of a precocious interest in pigments from the western European heartland of Palaeolithic painting into the Near East.
From a science future to a fantasy past
Authors: Irwin Robert
Published: November 2015

Once upon a time the characteristic way to transport the reader into another and different world was by science-fiction, through tales set into a supposed future. Now that genre is being swallowed by another, the fantasy fiction of sagas placed in a pretended past, whose usual descent is by California out of medieval, with Jean Auel’s tales of Palaeolithic Europe as a prehistoric variant. This new area of dominance for the past is worth an archaeological attention.
Local histories and global theories in Colombian Pacific coast archaeolgy
Authors: Stemper David M. , López Héctor Salgado
Published: November 2015

The Pacific Coast of Colombia has a complex history of change and upheaval. How is one to reach to it, with the variety of its human experiences? And how to grasp it from the diverse and often fragmentary sources that are its archaeology?
Pacbitun (Belize) and ancient Maya use of slate
Authors: Healy Paul F. , Awe Jaime J. , Iannone Gyles , Bill Cassandra
Published: November 2015

As well as jade, obsidian, chert and limestone, the Classic Maya of Central America were accomplished workers of another stone–slate. Recent research at the site of Pacbitun, Belize, where a possible slate workshop has come to light, is cause to look closely at Maya slate-working and the scientific means to study it.
Accelerator radiocarbon dating of the initial Upper Palaeolithic in southeast Siberia
Authors: Goebel Ted , Aksenov Mikhail
Published: November 2015

Across Eurasia and Africa new studies are encouraging archaeologists to rethink the age of of the Middle to Upper Palaeolithic transition. In the Lake Baikal region of southeast Siberia, new radiocarbon determinations on sites of difficult history suggest that the earliest Upper Palaeolithic emerged there as early as 39,000 years ago, 6000 years earlier than previously thought.
Microburins and microliths of the Levantine Epipalaeolithic: a comment on the paper by Neely & Barton
Authors: Kaufman Daniel
Published: November 2015

Issue is taken with the arguments offered by Neeley & Barton to explain interassemblage variability in the Epipalaeolithic. The techno-typological attributes they discuss do, indeed, mark cultural/temporal traditions and there are no grounds for viewing them as representing stages within a reduction sequence.
Politics and archaeology in the Canary Islands
Authors: Eddy Michael R.
Published: November 2015

The Canary Islands, 1000 km southwest into the Atlantic from Iberia, are close to the African coast; at the latitude of southern Morocco, they are far southern outliers to Europe as presently defined by its nation-states. The archaeology of their indigenous people, the Guanches, is caught up now in the contemporary politics of the Islas Canarias.
New light on Atlantic seaboard passage-grave chronology: radiocarbon dates from La Hougue Bie (Jersey)
Authors: Patton Mark
Published: November 2015

A series of dates for La Hougue Bie, the Jersey passage-grave, shows its complex history of abandonment as well as construction. People were a long time leaving, as well as making, this sacred place.
Archaeological data, subcultures and social dynamics
Authors: Matthews Keith J.
Published: November 2015

The archaeological record is dominated by the repeated object and the repeated event, so we search for patterns that explain the regular in general terms. But human societies are not like that; the mass is actually made up of individuals, and the engine of change more often at the margin than at the centre.
Comment on Pedra Furada
Authors: Dennell Robin , Hurcombe Linda
Published: November 2015

An issue in the status of the flaked stones from Pedra Furada, Brazil is whether they are artefacts or fractures naturally made on falling stone. An experiment by other researchers is pertinent.
Broad spectrum diets in arid Australia
Authors: Edwards Douglas A. , O'Connell James F.
Published: November 2015

A characteristic feature of human subsistence as the last glaciation ended was the turn towards new food sources, in a ‘broad spectrum’ transformation. Australia took an unusual course, and the trajectory in its arid zone is especially striking. What were the broad spectrum diets in arid Austalia? Why did they arise so late? Did they arise late?
Stone artefacts and the Transition
Authors: Holdaway Simon
Published: November 2015

Stone artefacts are made central in Australian prehistory by their dominance in the material we have from the field. Their contribution to this prehistory comes in the form of an unchanging tradition that spans the transition and changes only in the mid Holocene. This makes the Australian record almost unique in the world; but it is a uniqueness that may owe more to archaeological methods than cultural conservatism.
The forced repatriation of cultural properties to Tasmania
Authors: Murray Tim , Allen Jim
Published: November 2015

A recent court case in Australia changes the established frames under which research archaeologists, parks administrators and Tasmanian Aborigines deal with the prehistoric archaeology of the island.
The age of the Côa valley (Portugal) rock-art: validation of archaeological dating to the Palaeolithic and refutation of ‘scientific’ dating to historic or proto-historic times
Authors: Zilhão João
Published: November 2015

The dating studies of the ‘modern rock-art scientists’, when critically examined, are found not to show that the Côa valley petroglyphs are of recent age. Their Upper Palaeolithic characteristics, and therefore their likely late Pleistocene age, are consistent with their archaeological context.
Offshore islands and maritime explorations in Australian prehistory
Authors: Bowdler Sandra
Published: November 2015

The settlement of mainland Australia at an early (and uncertainly known) date required a water-crossing. What about the settlement of the islands — neither numerous nor large compared with the island continent itself — that are offshore from Australia? The evidence reviewed shows a late settlement for nearly all of them, and a perplexing lack of pattern.
On the question of silk in pre-Han Eurasia
Authors: Good Irene
Published: November 2015

When was silk first brought across the steppe from far China towards the European world? There is silk from the Middle Bronze Age of Uzbekistan, in Scythian burials of Siberia and among the Hallstatt grave-goods of western Europe. Teasing out the story of silk depends on identifying the textile, and distinguishing its several varieties apart.
Getting to the core of the problem: petrological results from the Irish Stone Axe Project
Authors: Cooney Gabriel , Mandal Stephen
Published: November 2015

When a distribution map of Neolithic stone axes in Ireland was published in ANTIQUITY (Grogan & Cooney 1990), the new Irish Stone Axe Project (ISAP) was mentioned. Stone axes, it turns out, are unusually common in Ireland. Here Project progress is outlined, with special attention being given to those axes identified as having been moved across the Irish Sea.
Early Upper Palaeolithic in the Russian Plain: Streletskayan flaked stone artefacts and technology
Authors: Bradley Bruce A. , Anikovich Michael , Giria Engenii
Published: November 2015

The artefact assemblages from early Upper Palaeolithic sites in eastern European Russia contain flint tools of more Middle Palaeolithic type. With these artefacts are bifacially thinned triangular forms that may represent the first use of this technology in the area, and perhaps anywhere in Europe.
An 8th-century Mercian bridge over the Trent at Cromwell, Nottinghamshire, England
Authors: Salisbury Chris
Published: November 2015

Heavyweight civil engineering in Romanized Europe means Roman, one thinks naturally enough. A tree-ring date now identifies a timber-framed bridge pier, previously thought Roman, as dating to the first half of the 8th century AD — Mercian, and the earliest known Saxon bridge in Britain.
Acorn-eating and ethnographic analogies: a reply to McCorriston
Authors: Mason Sarah L. R.
Published: November 2015

Joy McCorriston's paper in the March 1994 ANTIQUITY, on acorn-eating and agricultural origins, used California ethnographies as analogues for the ancient Near East. This reply explores some issues of analogy and explanation that go beyond the important specifics of the matter.
Sheep, stockyards and field systems: Bronze Age livestock populations in the Fenlands of eastern England
Authors: Pryor Francis
Published: November 2015

When Francis Pryor excavated the settlement complex on the dry gravels at Fengate, east England, he was a full-time archaeologist. Now that he is working at the adjacent wetland site of Flag Fen, he has also become a sheep-farmer. That practical experience leads him to a new view of what created the pattern of these planned later prehistoric landscapes.
Pedra Furada in Brazil and its ‘presumed’ evidence: limitations and potential of the available data
Authors: Parenti Fabio , Fontugue Michel , Guérin Claude
Published: November 2015

Recent prehistoric and palaeoanthropological debate is focusing new interest on the peopling of the Americas — an old and difficult research-case. Proponents of new sites need to submit their putative 'new and revolutionary' discoveries to a wider judgement, mainly contra sceptics and partisans of more conservative theories. Such a review is helpful, and we are grateful to our colleagues for their considered assessment of the evidence proposed in our Brazilian research. Nevertheless their view of the Pedra Furada evidence has gaps, misunderstandings and ambiguities.
More from the cutting edge: further discoveries of Clactonian bifaces
Authors: McNabb John
Published: November 2015

An important step in our knowledge of the British Lower Palaeolithic has been the finding that its two recognized components, ‘Clactonian’ and ‘Acheulean’, are not ranged into a simple sequence; the exact relationship between the two is the subject of much debate. What does this do to interpretations of Swanscombe, classic site of the Lower Thames Valley, which has been studied in terms of stratigraphic succession?
Intertidal Holocene footprints and their archaeological significance
Authors: Roberts Gordon , Gonzalez Silvia , Huddart David
Published: November 2015

The Holocene mud-flats of Formby Point, at the mouth of the Mersey estuary in northwest England, have long provided information about their palaeoenvironment. Now they yield a more direct evidence — in the form of preserved footprints — of the people and animals that frequented the foreshore.
A miniature antler bow from a Middle Bronze Age site at Isleham, (Cambridgeshire), England
Authors: Gdaniec Kasia
Published: November 2015

A little bow — at less than half a metre long too small to be a practical tool — comes from the later prehistoric Fenland of east England. Along with the wristguards, fine arrowheads and smoothing stones of the British Bronze Age, it tells of the special meaning of archery in later prehistory — whether in the animal chase or in human combat.
High-resolution satellite imagery in archaeological application: a Russian satellite photograph of the Stonehenge region
Authors: Fowler Martin J. F.
Published: November 2015

The spy satellites — by repute of the thriller writers — have such good image-resolution that they can read the letters on a vehicle licence-plate. A generation after LANDSAT imagery vividly showed broad ecological zones, higher resolution pictures are now being released of a quality to allow practical archaeological application. The example printed here illustrates the Stonehenge landscape — a little patch of southern England that is among the most photographed archaeologically anywhere.
Megalith-building, stone transport and territorial markers: evidence from Vale de Rodrigo, Évora, south Portugal
Authors: Kalb Philine
Published: November 2015

A further contribution concerning the moving of the great stones used in megalith-building in later prehistoric Europe.
An aerial archaeology training week, 15–22 June 1996, held near Siófok, Lake Balaton, Hungary
Authors: Bewley Robert , Braasch Otto , Palmer Rog
Published: November 2015

The end of the Cold War in 1989 prompted the opening of central European skies that had been closed to archaeological air photography for decades. The occasion of a summer school in 1996 provided the opportunity to record some results from Hungary.
Early human occupation of northern Australia: archaeology and thermoluminescence dating of Jinmium rock-shelter, Northern Territory
Authors: Fullagar R. L. K. , Price D. M. , Head L. M.
Published: November 2015

The nature and date of the human colonization of Australia remains a key issue in prehistory at the world scale, for a sufficiently early presence there indicates either Homo sapiens sapiens arriving precociously in a place remote from a supposed African origin, or a greater competence in sea-crossing than has been expected of archaic humans. Stratigraphic integrity, the new science of luminescent dating and the recognition of worked stone and of rock-engraving are immediate issues in this report from far northwestern Australia.
Zemís, trees, and symbolic landscapes: three Taíno carvings from Jamaica
Authors: Saunders Nicholas J. , Gray Dorrick
Published: November 2015

Three carved wooden images have come to light in Jamaica, the most important find of Taíno carvings for two centuries from that island. Their discovery prompts a reconsideration of Taíno zemís, and their placing into the known context of the Caribbean region, with its South American links.
4000 years of human impact and vegetation change in the central Peruvian Andes — with events parallelling the Maya record?
Authors: Chepstow-Lusty A. J. , Bennett K. D. , Switsur V. R. , Kendall A.
Published: November 2015

A lake-sediment sequence from Marcacocha in the central Peruvian Andes provides a well-dated and continuous vegetation record from an area rich in Inca and pre-Inca remains over the last 4000 years. Climatic changes in this record at AD 1–100 and AD 900–1050 seem to be broadly contemporaneous with major arid events from Lake Chichancanab, Mexico, affecting the Maya civilization and corroborated by the Quelccaya and Huascaran ice cores in Peru.
People, process and the poverty-pew: a functional analysis of mundane buildings in the Nottinghamshire framework-knitting industry
Authors: Campion Garry
Published: November 2015

Industrial archaeology has traditionally concentrated on the recording and study of technological and engineering survivals — hence the name ‘industrial’ as, often, a near-synonym for ‘post-medieval’ in naming the archaeology of early modern capitalism. This study of three mundane industrial buildings draws upon building and documentary evidence as aids to understanding working structures not distinguished by technological or engineering innovation.
Dryland agricultural expansion and intensification in Kohala, Hawai'i island
Authors: Ladefoged Thegn N. , Graves Michael W. , Jennings Richard P.
Published: November 2015

Intensified dryland agriculture was a component of the late prehistoric Hawaiian subsistence base. Which environmental factors permitted, encouraged, restricted, blocked the spreading of intensive agriculture into new areas of fields? A GIS study of the great field system at Kohala on the leeward side of Hawai'i Island explores the controlling variables.