bluuebunny/crossref_metadata_2025 huggingface dataset:
Supercritical fluid extraction of minor lipids from pretreated sunflower oil deodorizer distillates
Authors: Vázquez Luis , Torres Carlos F. , Fornari Tiziana , Grigelmo Nuria , Señoráns Francisco J. , Reglero Guillermo
Published: July 2006

The recovery of minor lipid compounds (tocopherols and phytosterols) from sunflower oil deodorizer distillates using countercurrent supercritical carbon dioxide extraction has been studied. Since the raw material employed contains large amounts of triacylglycerols and free fatty acids, chemical transformation of these compounds into their corresponding fatty acid ethyl esters was previously carried out, in order to favor the concentration of minor lipids in the raffinate product. Extractions of the original and pretreated raw material were carried out in a pilot‐scale plant at 65 °C, with pressures ranging from 15 to 23 MPa and solvent‐to‐feed ratios from 15 to 30. The influence of the feed composition in the extraction process was analyzed by comparison of the tocopherol and phytosterol yields and enrichment factors obtained in each case. The chemical transformation of the deodorizer distillate composition significantly enhances the concentration of minor lipids in the raffinate product. Additionally, the reaction step produced a solid phase, mainly consisting of sterols, which was isolated from the liquid product.
Hydrolysis of fatty acid esters in subcritical water
Authors: Kocsisová Teodora , Juhasz Jozsef , Cvengroš Ján
Published: July 2006

Hydrolysis of esters of higher fatty acids by subcritical water, performed in a flow‐through tubular reactor, was investigated at temperatures from 280 up to 340 °C and pressures exceeding 12 MPa, using an ester/water ratio of 1 : 2 or 1 : 4 (vol/vol). The kinetics of the hydrolysis of both the triacylglycerols and the methyl esters obeyed the rate equation valid for first‐order reactions. Conversion of the esters to free fatty acids exceeding 95% was reached at the temperature of 340 °C during 12 min. IR spectroscopy revealed structural changes in the chains of the unsaturated fatty acids and their partial polymerization during the hydrolysis.
Effect of dewaxing pretreatment on composition and stability of rice bran oil: Potential antioxidant activity of wax fraction
Authors: Mezouari Samia , Kochhar S. Parkash , Schwarz Karin , Eichner Karl
Published: July 2006

The effect of dewaxing pretreatment on rice bran oil composition and stability was investigated, as well as the possibility to use rice bran oil waxes as natural antioxidants at high temperatures. A correlation between wax content and dewaxing time was noticed. The pre‐dewaxing process led to a loss of minor compounds, which negatively affected the oxidative stability index (OSI) of the dewaxed oil. The addition of rice bran oil waxes improved the oil stability index and heat stability of sunflower oil. An increase of 60% of the OSI and a significant decrease in polymer formation (59.2%) were observed.
Amplitude, frequency, and phase analysis of hippocampal theta during sensorimotor processing in a jump avoidance task
Authors: Bland Brian H. , Jackson Jesse , Derrie‐Gillespie Donna , Azad Tanjeem , Rickhi Anil , Abriam Jason
Published: July 2006

In the current study, rats implanted with hippocampal recording electrodes were trained to avoid shock in a jump avoidance task, using three separate heights, 28, 33, and 38 cm. The objectives were to measure the progression of Type 2 (immobility‐related) hippocampal theta amplitude and frequency recorded during jump avoidances at each of the levels, and determine if there was a consistent relationship between the phase of the Type 1 (movement related) theta jump wave and the moment of movement initiation at each of the jump heights. The results demonstrated that the immobility period prior to the execution of the jump could be divided into two components: a sensory processing period and a movement preparation period. Comparing these two periods, average amplitudes were higher while frequency remained relatively constant during the sensory processing period. During the movement preparation period there was a negative correlation between amplitude and frequency: amplitude declined rapidly and frequency increased rapidly. During the execution of the jump, theta amplitude (Type 1) and frequency were positively correlated, both reaching peak values. The separate analyses of the individual jump heights provided further support for the precise relationships between theta parameters and the magnitude of the required movements. A significant phase preference was demonstrated for the highest jump height, with movement initiation occurring around the trough of theta recorded from the stratum moleculare of the dentate region. The findings supported the conclusion that the generation of hippocampal theta band oscillation and synchrony was related to sensorimotor processing and integration. © 2006 Wiley‐Liss, Inc.
Lung cancer risk among US radiologic technologists, 1983–1998
Authors: Rajaraman Preetha , Sigurdson Alice J. , Doody Michele M. , Freedman D. Michal , Hauptmann Michael , Ron Elaine , Alexander Bruce H. , Linet Martha S.
Published: July 2006

While exposure to moderate to high‐dose ionizing radiation is an established risk factor for lung cancer, the relationship between lung cancer and chronic low dose radiation remains uncertain. We examined lung cancer risk among 71,894 US radiologic technologists who were certified during 1926–1982, responded to a baseline questionnaire (1983–1989), and were free of cancer other than non‐melanoma skin cancer at baseline. Study participants were followed until completion of a second questionnaire (1994–1998), death, or August 31, 1998. We identified 287 lung cancer cases: 66 incident cases and 221 decedents. Exposure to radiation was inferred based on work history information provided in the baseline questionnaire. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazard models adjusted for age, race/ethnicity and smoking. Smoking‐adjusted lung cancer risk was not related to working as a radiologic technologist in early years when radiation exposures were likely highest (RR = 0.9; 95% CI, 0.5–1.8 for year first worked before 1940 compared to year first worked ≥1960), nor was risk related to the year first worked after 1940 or the number of years worked in any decade. While lung cancer risk was increased in radiologic technologists who held patients for X‐rays, or who allowed others to take numerous practice X‐rays on them, the trend was not statistically significant in either case. Although we adjusted for smoking, the possibility of residual confounding exists. Overall, we find very limited evidence that chronic low‐to‐moderate dose occupational exposure increased lung cancer risk in the US Radiologic Technologist cohort. © 2006 Wiley‐Liss, Inc.
Benzo(a)pyrene‐induced acute neurotoxicity in the F‐344 rat: role of oxidative stress
Authors: Saunders Crystal R. , Das Salil K. , Ramesh Aramandla , Shockley Dolores C. , Mukherjee Shyamali
Published: July 2006

Given the link between neurotoxicity and exposure to pollutants, the potential behavioral neurotoxicity of benzo(a)pyrene [B(a)P] was investigated. Studies have established that B(a)P requires metabolic activation to highly reactive species to elicit many of its adverse effects. This study investigated the perturbation of nervous system function by correlating behavioral changes with the metabolism of B(a)P, antioxidant enzyme levels and lipid peroxidation in selected brain regions. The neurobehavioral effects of single oral doses of B(a)P (25–200 mg kg−1body weight) on motor activity were examined in male F‐344 rats at 2, 4, 6, 12, 24, 48, 72 and 96 h post treatment. Parent B(a)P and metabolites were measured at the above mentioned time points by reverse phase HPLC. The activity of several antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) and levels of malondialdehyde were determined at 6 and 96 h in both the striatum and hippocampus of B(a)P exposed rats. Suppression of motor activity (up to 70%) reached a maximum at 6 h, but was reversible at 96 h in all dose groups. The kinetics of disposition data show a strong link between B(a)P metabolism and the onset and duration of behavioral effects. Benzo(a)pyrene caused a 15–70% inhibition in the activity of superoxide dismutase and glutathione peroxidase and an enhancement in catalase and lipid peroxidation (up to 68%) in the striatum and hippocampus at 6 and 96 h post treatment, respectively. These findings suggest that B(a)P‐induced acute neurobehavioral toxicity may occur through oxidative stress due to inhibition of the brain antioxidant scavenging system. Copyright © 2006 John Wiley & Sons, Ltd.
Einfluß von Futterfetten und ‐lecithinen auf Parameter der Infektionsabwehr beim Absatzferkel, 1. Mitteilung: Der Einfluß von Soja‐ oder Rapsöl
Authors: Brinkmann Gerlinde , Molnar Sandor
Published: July 2006

In einem Versuch mit 30 Absatzferkeln wurde der Einfluß von Sojaöl oder Rapsöl auf Parameter der Infektionsabwehr untersucht. Die Versuchstiere erhielten 39 Tage lang eine Diät auf Getreidebasis, in der entweder 6% Sojaöl, 6% Rapsöl oder 13,8% Maisquellstärke (Kontrolle) isoenergetisch gegen eine Getreidekomponente ausgetauscht wurden. Die Infektionsparameter wurden am 0., 12., 19., 26. und 39. Versuchstag (VT) erfaßt. Sowohl 6% Sojaöl als auch 6% Rapsöl in der Ration erhöhten die Werte des unspezifischen Abwehrsystems wie die Nitroblautetrazolium‐Reduktionskapazitäten (am 26. und 39. VT), die Lysozymkonzentrationen (am 12., 19. und 39. VT) und die Granulozytengehalte (am 19. und 26. VT) signifikant im Vergleich zur Kontrollgruppe.
Bestimmung der Linol‐ und Linolensäure in Margarine, Halbfettmargarine und Mischfetten – Deutsche Einheitsmethoden zur Untersuchung von Fetten, Fettprodukten, Tensiden und verwandten Stoffen: Analyse von fettreichen Lebensmitteln VI
Authors: Fiebig H.‐J. , Gertz Chr.
Published: July 2006

Der “Gemeinschaftausschuß für die Analytik von Fetten, Ölen, Fettprodukten, verwandten Stoffen und Rohstoffen (GAFett)” hat die nachfolgende Methode zur Bestimmung der Linol‐ und Linolensäure in Margarine, Halbfettmargarine und Mischfetten verabschiedet. Sie soll in die Abteilung K, Kapitel I, der DGF‐Einheitsmethoden aufgenommen werden. Kommentare zu dieser Methode werden an die Berichterstatter erbeten.
A Novel Approach to Prepare a Gradient Polymer with a Wide Damping Temperature Range by In‐Situ Chemical Modification of Rubber During Vulcanization
Authors: Wang Yi‐Qing , Wang Ya , Zhang Hui‐Feng , Zhang Li‐Qun
Published: July 2006

Summary: Based on the fact that rubber can be chemically modified by sulfur, and sulfur can diffuse into rubber driven by a concentration gradient and chemical reaction, a new approach for the preparation of a polymer with a gradient from rubbery to glassy phase has been developed using the sulfur‐vulcanization reaction of rubber. The gradient polymer obtained exhibits a wide transition range spanning over 100 °C with a peak half‐width of 69 °C. The mechanism of forming the gradient structure is also discussed.

The gradient polymer exhibits a broad tan δ width from −60 to 76 °C with the peak half‐width spanning about 69 °C, indicating a wide damping temperature range.

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The gradient polymer exhibits a broad tan δ width from −60 to 76 °C with the peak half‐width spanning about 69 °C, indicating a wide damping temperature range.
Patterning Proteins on Surfaces of Cross‐Sectioned Multilayer Polymer Films
Authors: Zhang Chun , Husson Scott M. , Hirt Douglas E.
Published: July 2006

Summary: A new approach is introduced to create submicrometer patterned surfaces using multilayer polymer films that contain alternating layers of two polymers, linear low‐density polyethylene (LLDPE) and ethylene‐co‐(acrylic acid) copolymer (EAA). Patterned templates have been prepared by microtoming the multilayer molded sheets. Regionally confined chemical functionality is confirmed by grafting an amine‐terminated biotin and adsorbing streptavidin specifically on the alternating layers of EAA.

Fluorescence micrograph of the Alexa488‐streptadivin patterned polymer surface.

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Fluorescence micrograph of the Alexa488‐streptadivin patterned polymer surface.
Physically and Chemically Crosslinked Gelatin Gels
Authors: Hellio Dominique , Djabourov Madeleine
Published: July 2006

In this paper, we examine the rheological and the structural properties of different types of gelatin networks, physical, chemical and both. The physical gel is due to the formation of collagen type triple helices when cooling the solutions. Chemically crosslinked gels are obtained with a reagent, in our case the bis(vinylsulfonyl)methane (BVSM), kindly provided by Kodak Industrie (France). Each BVSM molecule provides two covalent bonds. The chemical reaction was followed by microcalorimetry (MicroDSC III from Setaram, Caluire, France). The relation between shear moduli and crosslinking for the three types of gels is discussed, in relation with theoretical models of randomly crosslinked systems.
Disorder Effects in “Plastic” and Highly Conducting Compounds of Poly(aniline)
Authors: Djurado David , Sniechowski Maciej , Bée Marc , Johnson Mark , Gonzalez Miguel A. , Rannou Patrice , Pron Adam
Published: July 2006

Numerical methods of molecular dynamics have been combined to measurements of X‐ray and neutron scattering in order to obtain a realistic view of structural and dynamical disorder properties of conducting compounds of so called “plastdoped” poly(aniline)s. This combination allowed us to propose for the whole family of these compounds one generic model of a layered structure in which exist statistical fluctuations of the electronic density along the stacking direction of alternating molecular layers. The most part of the dynamics in the 10−13–10−9 s time range concerns the motions of protons borne by the flexible tails of doping counter‐ions contained in the structure. We found that the molecular dynamics is characterized by both broad time and spatial distributions. These experimental facts coupled to those obtained with electrical conductivity measurements indicate that the high mobility of the counter‐ion sublattice seems to be a prerequisite to promote a global metal like electronic behaviour of the polymer films.
An AFM Study of Poly(L‐lactic acid) and Poly(D‐lactic acid) Macromolecules and Their Stereocomplexes at the Solid‐Air Interface
Authors: Narladkar Ashok , Balnois Eric , Grohens Yves
Published: July 2006

The self assembly of PLA enantiomers have been studied at the nanometer scale using atomic force microscopy. At first, the conformation of D and L PLA macromolecules in dilute regime and the initial state of aggregation of both enantiomers were successively observed and compared with the aggregation of PLLA/PDLA blends. Our results points out differences in the aggregates structure between the homo‐aggregates of each enantiomers and the 3 Dimensional stereocomplexes formed with racemic mixture of D and L entities. On the one hand, D or L PLA chains, which adopt a rigid conformation in dilute regime, form gradually aggregates that tend to grow from a nucleation center. On the other hand, stereocomplexes have a non‐compact structure and are elongated with height variations within the fibrils that support the side by side aggregation of D and L helical structures to form thicker fibrils.
Self‐Assembled Nanotubes in Organic Solvents
Authors: Diáz Nancy , Simon François‐Xavier , Schmutz Marc , Mésini Philippe
Published: July 2006

Self‐assembled nanotubes are formed spontaneously in alkane solvents by a simple diamide compound: the 3,5‐Bis‐(5‐hexylcarbamoyl‐pentyloxy)‐benzoic acid decyl ester (BHPB‐10). The tubular shape was proved by freeze fracture TEM and by SANS techniques. The tubes have a mean radius of 121 Å and a length of the order of a micron. BHPB‐14, a homologue of this compound, bearing a longer ester chain (C14 instead of C10), self‐assemble into flat ribbons under the same conditions. FTIR and UV spectroscopy showed that H‐bonds between amide groups and π‐π interaction between aromatic groups are involved in both kinds of aggregates and in the solid state as well. The nanotubes feature specific interactions between the ester carbonyls. Hence we show that ester, by its length and by the interactions between carbonyls determines the formation of nanotubes.
Organogelators and Polymer Crystallisation
Authors: Thierry Annette , Straupé Christine , Wittmann Jean‐Claude , Lotz Bernard
Published: July 2006

The specific impact of low molecular weight organic gels on polymer crystallisation is examined. Conventional nucleating agents (NA) influence the polyolefins crystallisation and improve their mechanical properties, via an epitaxial mechanism. In the particular case where the pair NA/polymer form a gel at intermediate temperatures on cooling, optical properties (clarity) are significantly improved. This improvement is linked with the ability of organic gels to develop 3‐D fibrillar network. The fibres morphology offers a large specific area, thus produces a high density of nuclei, homogeneously dispersed. Gelling organic molecules are certainly a promising route towards the design of efficient additives in polymer processing.
Hierarchical reporting, aggregation, and information cascades
Authors: Arya Anil , Glover Jonathan , Mittendorf Brian
Published: July 2006

Aggregation is commonly associated with loss of information. In contrast, this paper shows that aggregation can actually enhance information down‐the‐road by deterring information cascades. In particular, when hierarchical tiers forward only aggregate recommendations rather than nitty‐gritty details, it increases the uncertainty faced by subsequent tiers. This makes individuals at higher levels more willing to rely on and convey their own views rather than simply rubber stamping suggestions from lower levels. Copyright © 2006 John Wiley & Sons, Ltd.
Attitudes towards sex selection for non‐medical reasons: a review
Authors: Hall Sue , Reid Erin , Marteau Theresa M.
Published: July 2006

Early non‐invasive fetal sexing is widely available over the Internet, leading to concerns about its possible use for sex selection. The aim of this review is to summarise the results of surveys describing lay attitudes towards sex selection for non‐medical reasons to help address or inform such concerns. A search of electronic databases and key journals was supplemented by an Internet search and citation‐tracking. Twenty‐one quantitative studies were identified. Most were conducted in the US, with five recent studies in the UK and Germany. Most studies found that, overall, people were not in favour of sex selection. However, this varied from 94 to 18%. People may hold more negative attitudes when the method of sex selection is specified, particularly if this involves termination of pregnancy (TOP). Attitudes towards the general availability of sex selection are less negative than those towards personal use. Attitudes were consistently negative in German surveys. Little is known of such attitudes outside the US, the UK and Germany, and how such attitudes may change as new sex selection technologies become available. Studies of use of early non‐invasive fetal sexing for sex selection for non‐medical reasons are needed to assess the extent to which concerns about usage are justified and to assist in debates on how these might be most appropriately addressed. Copyright © 2006 John Wiley & Sons, Ltd.
Regulating post‐implantation fetal sex selection: a UK perspective
Authors: Newiss Hilary
Published: July 2006

This article reviews the current and potential laws relevant to post‐implantation fetal social sex selection and considers whether they could provide an effective deterrent and control of the practice, if the United Kingdom decided that such control were desirable. It concludes that enacting, drafting and enforcing of any legislation throws up many difficult practical and ethical issues. These issues need to be debated and further information collected before any legislation is rushed into. Copyright © 2006 John Wiley & Sons, Ltd.
Attitudes to and practices regarding sex selection in China
Authors: Cecilia Lai‐wan Chan , Eric Blyth , Celia Hoi‐yan Chan
Published: July 2006

This paper explores the problem of China's ‘missing’ girls—estimated to run into many millions. It considers the impact of the underpinning Confucian value system in China that has produced a culture of son preference and which, together with China's compulsory family planning program and ‘one child policy’, has effectively established a ‘one son policy’. Discussion of the various means by which the birth or survival of daughters have traditionally been prevented provides the context for identifying the contribution of new sex selection procedures to the maintenance of son preference in contemporary Chinese society. The paper concludes that China's son preference is not simply a personal problem for the millions of ‘missing girls’ who were destined to live a shorter life and for the surviving girls who continue to face considerable discrimination simply because they are of the ‘wrong’ sex; it heralds a social and demographic disaster of major proportions for which neither the government nor the people of China appear to have the will or the means to forestall. Copyright © 2006 John Wiley & Sons, Ltd.
‘Reproductive autonomy’ versus public good?
Authors: O'Neill Onora
Published: July 2006

Hitherto sex selection could be achieved only by destroying any fetus or child of the unwanted sex. Sperm selection may change that. The technology could be used to ‘balance’ families. However its use in certain developing countries might ‘unbalance’ populations, with serious, if unintended, consequences. Copyright © 2006 John Wiley & Sons, Ltd.
Changes in emotion regulation and psychological adjustment following use of a group psychosocial support program for women recently diagnosed with breast cancer
Authors: Cameron Linda D. , Booth Roger J. , Schlatter Melanie , Ziginskas Danute , Harman John E.
Published: July 2006

This study assesses the efficacy of a group intervention in altering emotion regulation processes and promoting adjustment in women with breast cancer. Using a design with 10 alternating phases of availability of the intervention versus standard care, we assessed women participating in one of three conditions: a 12‐week group intervention (N = 54); a decliner group who refused the intervention (N = 56), and a standard care group who were not offered the intervention (N = 44). The intervention included training in relaxation, guided imagery, meditation, emotional expression, and exercises promoting control beliefs and benefit‐finding. Emotion regulation processes and adjustment were assessed at baseline (following diagnosis), 4 months (corresponding with the end of the intervention), 6 months, and 12 months. At 4 months, intervention participants (compared to decliners and standard care participants) reported greater increases in use of relaxation‐oriented techniques, perceived control, emotional well‐being, and coping efficacy, and, greater decreases in perceived risk of recurrence, cancer worry, and anxiety. Intervention participants also reported relatively greater decreases in emotional suppression from baseline to 12 months, suggesting that the intervention had a delayed impact on these tendencies. The findings suggest an emotion regulation intervention can beneficially influence emotional experiences and regulation over the first year following diagnosis. Copyright © 2006 John Wiley & Sons, Ltd.
A bronchoscopic scoring system for airway secretions—airway cellularity and microbiological validation
Authors: Chang A.B. , Faoagali J. , Cox N.C. , Marchant J.M. , Dean B. , Petsky H.L. , Masters I.B.
Published: July 2006

There is currently no validated scoring system for quantification of airway secretions in children. A user friendly, valid scoring system of airway secretions during flexible bronchoscopy (FB) would be useful for comparative purposes in clinical medicine and research. The objective of this study was to validate our bronchoscopic secretion (BS) scoring system by examining the relationship between the amount of secretions seen at bronchoscopy with airway cellularity and microbiology. In 106 children undergoing FB, the relationship of BS grades with bronchocalveolar lavage (BAL) cellularity and infective state (bacterial and viral infections) were examined using receptor operator curves (ROC). BAL was obtained according to European Respiratory Society guidelines; first lavage for microbiology and second lavage for cellularity. Area under the ROC was significant for total cell count (TCC) and neutrophil % but not for lymphocyte %. BS grade significantly related to infection positive state (χ = 5.85, P = 0.016). The area under the ROC for infection positive state versus BS grade was 0.645, 95% CI 0.527–0.763. The BS scoring system is a valid method for quantifying airway secretions in children undergoing bronchoscopy. The system related well to airway cellularity and neutrophilia, as well as to an airway infective state. However, the system is only complementary to cell counts and cultures and cannot replace these laboratory quantification techniques. Pediatr Pulmonol. © 2006 Wiley‐Liss, Inc.
Factors affecting culvert use by vertebrates along two stretches of road in southern Portugal
Authors: Ascensão Fernando , Mira António
Published: July 2006

A major target for environmental managers when trying to minimise the road‐barrier effect on wildlife is to improve permeability to animal movements. Previous studies have demonstrated that drainage culverts are used by vertebrates, although knowledge of the main influencing factors remains limited. The use of 34 culverts from two roads in southern Portugal, differing in traffic volume, vehicle speeds and configuration, was evaluated by the analysis of terrestrial vertebrate footprint data (408 passage‐operative days). Culvert crossings were related to various explanatory variables by means of canonical ordination techniques. We recorded 901 complete crossings, corresponding to an average of 2.2 crossings/culvert/operative day. Thirteen taxa were detected, all in more than one passage. Animal species included reptiles, small mammals, lagomorphs, carnivores and domestic dogs and cats. Our results suggest that fencing might have a funnelling effect, directing larger animals toward culverts. Also, vegetation covering culvert entrances seems to have a positive effect, particularly on genets; longer passages with entrances far from the pavement were, apparently, avoided by smaller animals; a lower number of crossings was detected on passages with detritus pits; the closest passages to urban areas are more often used by domestic species; forest‐living species favour passages with low, open land cover nearby; and smaller species, like lagomorphs and small mammals, appear to use more culverts near the pavement, which probably reflects the importance of road verges as refuges for these species. Although not used by all species present in the study area, constructing numerous passages of different sizes without detritus pits and which are distributed along roads might be an important step in mitigating road fragmentation effects on animal populations.
Shoreline Changes Along the Southeastern Coast of Martha's Vineyard, Massachusetts for the Past 200 Years
Authors: Ogden J.Gordon
Published: July 2006

Shoreline changes since 1776, including two 30-yr periods separated by nearly 100 yr are documented from surveys, topographic maps, harbor charts, and aerial photographs for the southeastern corner of the island of Martha's Vineyard, Massachusetts (41°25′ N, 70°35′ W). From 1776 to 1969, a barrier beach has receded by more than 880 m, and average rate of 4.6 m/yr. A series of four detailed surveys from 1840 to 1886 document consistent shoreline retreat in this area of 3.1 m/yr.

For the period 1938–1969, planimetry from aerial photographs and field observation indicate that more than 28 ha and nearly 3 × 106 m3 of foreland composed of till have washed away. A house, located 200 m from the cliff edge of the foreland in 1938 was only 56 m from the cliff edge in July 1972.

Violent storms were associated with the opening of the bay behind the barrier beach in nearly the same location in 1856, 1886, 1938, and 1954. Easterly migration of the opening results in rapid erosion of the southeastern corner of the island (Wasque Point) and eventual closing of the opening.

Field observation of the 1954 opening indicates that the mechanism of failure of the barrier beach is primarily by storm tide-induced subsidence. Subsequently, strong (up to 1.2 mps) easterly currents cause migration of the opening to the east and closure within 15 yr.

A summary review of evidence for changes in sea level in the past is suggested in partial explanation for the consistent shoreline retreat described in this paper.
Apparent Radiocarbon Ages of recent marine shells from Norway, Spitsbergen, and Arctic Canada
Authors: Mangerud Jan , Gulliksen Steinar
Published: July 2006

The mean apparent radiocarbon ages of marine shells, colleted alive before the initiation of atomic bomb testing, and also before the main input of dead carbon derived from fossil fuels, are found to be 440 yr for the coast of Norway, 510 yr for Spitsbergen, and 750 yr for Ellesmere Island, Arctic Canada. The relationship between these apparent ages and the oceanic circulation pattern, is discussed. Also possible variations of the apparent ages back in time are discussed.
The Relevance of Old World Archeology to the first Entry of Man into the New World
Authors: Klein Richard G.
Published: July 2006

Archeological evidence from the USSR suggests that cultural adaptations to the most rigorous (most continental) environments of northern Eurasia were not achieved until 35–40,000 BP. This presumably sets an absolute basement date for the entry of man into Alaska through the region of Beringia. The absence of evidence for pre-14,000 yr old man in the 48 adjacent United States comparable in any sense to the evidence that has been developed for man prior to 14,000 y.a. in the Old World suggests that movement south out of Alaska only occurred after 14,000 BP.
An Overview of Climatic Variability and its Causal Mechanisms
Authors: Mitchell J. Murray
Published: July 2006

A variance spectrum of climatic variability is presented that spans all time scales of variability from about one hour (10−4 years) to the age of the Earth (4 × 109 years). An interpretive overview of the spectrum is offered in which a distinction is made between sources of variability that arise through stochastic mechanisms internal to the climatic system (atmosphere-ocean-cryosphere) and those that arise through forcing of the system from the outside. All identifiable mechanisms, both internal and external, are briefly defined and clarified as to their essential nature. It is concluded that most features of the spectrum of climatic variability can be given tentatively reasonable interpretations, whereas some features (in particular the quasi-biennial oscillation and the neoglacial cycle of the Holocene) remain fundamentally unexplained. The overall spectrum suggests the existence of a modest degree of deterministic forms of climatic change, but sufficient nonsystematic variability to place significant constraints both on the extent to which climate can be predicted, and on the extent to which significant events in the paleoclimatic record can ever manage to be assigned specific causes.
Late Pleistocene and Holocene Climates: Some Persistent Problems
Authors: Hare F. Kenneth
Published: July 2006

A series of lectures as comprehensive as those reported in this issue leaves very little for a general reviewer to say. The lecturers have included many of the leading specialists in each of the subfields of palaeoclimatology, upon whose work a reviewer must lean. Moreover there has recently been published a fine synthesis of what is known about the overall character of Quaternary and Holocene climates (U.S. GARP Committee, 1974) (hereafter referred to as GARP-74). All I can do in this situation is to point out some disturbing and persistent problems that tend to defy solution.
Pollen Distribution in the Northeast Pacific Ocean
Authors: Heusser Linda , Balsam William L.
Published: July 2006

Distributional patterns of palynomorphs in core tops from the continental margin of the northeast Pacific Ocean (30°–60°N lat 118°–150°W long) reflect the effects of fluvial and marine sedimentation as well as the distribution of terrestrial vegetation. Maximum pollen concentration (grains/cm3 of marine sediment) occurs off the mouth of the Columbia River and off San Francisco Bay (the outlet of the San Joaquin and Sacramento Rivers) and appears to be coincident with areas of high terrigenous lutite deposition. The abundance of pollen and spores in shelf sediments is extremely variable with high concentrations typical only of the finest sediments. On the slope, rise and abyssal plain, pollen concentration shows a general decrease with distance from shore. This suggests that in the northeast Pacific pollen is transported into the marine environment primarily by rivers and that, in terms of sedimentation, pollen may be regarded as part of the organic component of fine-grained lutum.

Pinus, the principal pollen component of marine sediment on the northeast Pacific margin, is concentrated adjacent to the major drainage systems of areas in which pine grows. Tsuga heterophylla, Picea, and Alnus, important components of the temperate conifer forest, are concentrated off the area of their optimal development, western Washington. Quercus, Sequoia, and Compositae concentrations are greater off the southern California coast where they are prominent in the vegetation. The relative (percent) abundance of most of these pollen taxa in marine sediments reflects a positive relationship to their distribution on land. Picea and Alnus are relatively more important north of 45°N, Tsuga heterophylla between 45°–50°N, and Quercus, Sequoia, and Compositae south of 40°N. Pine percentages increase seaward, from less than 10% of the pollen sum in shelf sediments to over 50% in sediments on the abyssal plain. This seems to indicate selective transport of pine pollen. Factor analysis of pollen data from the 61 core tops results in four pollen assemblages. Three of these assemblages (Quercus-Compositae-Sequoia, Tsuga heterophylla-Pinus, and Alnus-Picea) reflect the distribution of vegetation on the adjacent continent, one (Pinus) reflects primarily the effects of marine sedimentation.
Geology of the Dry Creek Site; a Stratified Early Man Site in Interior Alaska
Authors: Thorson Robert M. , Hamilton Thomas D.
Published: July 2006

The Dry Creek archeologic site contains a stratified record of late Pleistocene human occupation in central Alaska. Four archeologic components occur within a sequence of multiple loess and sand layers which together form a 2-m cap above weathered glacial outwash. The two oldest components appear to be of late Pleistocene age and occur with the bones of extinct game animals. Geologic mapping, stratigraphic correlations, radiocarbon dating, and sediment analyses indicate that the basal loess units formed part of a widespread blanket that was associated with an arctic steppe environment and with stream aggradation during waning phases of the last major glaciation of the Alaska Range. These basal loess beds contain artifacts for which radiocarbon dates and typologic correlations suggest a time range of perhaps 12,000–9000 yr ago. A long subsequent episode of cultural sterility was associated with waning loess deposition and development of a cryoturbated tundra soil above shallow permafrost. Sand deposition from local source areas predominated during the middle and late Holocene, and buried Subarctic Brown Soils indicate that a forest fringe developed on bluff-edge sand sheets along Dry Creek. The youngest archeologic component, which is associated with the deepest forest soil, indicates intermittent human occupation of the site between about 4700 and 3400 14C yr BP.
Radiocarbon Dating of Quaternary Loess Deposits, Banks Peninsula, Canterbury, New Zealand
Authors: Goh K.M. , Molloy B.P.J. , Rafter T.A.
Published: July 2006

Quaternary loess deposits containing charcoal and in situ organic matter constituents from Banks Peninsula, New Zealand, were subjected to various physical and chemical treatments before radiocarbon assay. A stepwide procedure was used in which each component was radiocarbon dated before and after the treatments were applied. The criterion adopted for judging the effectiveness of a treatment is an increase in the radiocarbon age of loess layer. On this basis the oldest and therefore the most reliable date was obtained from the intra-loess charcoal and its humic acid extract. By comparison, the radiocarbon ages of organic matter constituents of the whole or partitioned loess were much younger, and are considered to represent only average ages for the particular layers concerned. No advantage was gained by dating the carbon-enriched clay-humus fraction as opposed to whole loess samples. There is an apparent conflict between our dates and current interpretation of loess stratigraphy and chronology in the South Island of New Zealand, which requires further investigation. This uncertainty apart, the upper layers of multiple loess deposits are clearly much older than earlier reports indicate, and it follows that the correlation of these deposits with late-glacial events both within and beyond New Zealand is even more tenuous and unreliable than previously thought to be the case.
Thoughts on the Initial Adaptation of Hominids to European Glacial Climates
Authors: Bordes Fr. , Thibault Cl.
Published: July 2006

The African continent has afforded a wealth of evidence bearing on the early evolution of Hominidae and the development of capacities for culture. However, until recently there has been scant documentation of the time of dispersal of hominids from tropical into north temperate latitudes. Human populations were certainly well established in Europe by Mindel Glacial times, rather less than 0.7 my ago, to judge from known occupation places in France and Hungary. Recently several localities in southern France and southern Spain have afforded artifactual evidence to suggest the presence of human populations in the preceding Cromerian interglacial, and even very probably in the preceding glacial stage, the “Gunz” (of authors). The identity of these first Europeans still remains unknown.
Paleo-Indian Procurement of Camelops on the Northwestern Plains
Authors: Frison George C. , Walker Danny N. , Webb S. David , Zeimens George M.
Published: July 2006

Camelops have been recorded in a number of Paleo-Indian sites that lack evidence of past procurement methods. Recently, two occurrences of Camelops remains have been recorded in Paleo-Indian animal kills in Wyoming. One kill situation was in a Hell Gap cultural context that produced remains of a single Camelops taken along with about 100 bison in a parabolic sand dune trap. The other Camelops was in a Clovis cultural context and deals with a single animal believed to have been taken in an arroyo trap that was used to take bison at several Paleo-Indian time periods. Identification of geomorphic features involved in these kill sites offers a basis for beginning to interpret Paleo-Indian camel procurement methods.
Dendrogeomorphological Analysis of Mass Movement on Table Cliffs Plateau, Utah
Authors: Shroder John F.
Published: July 2006

A rock glacier-year, with little evidence of long-term surges. Different parts of the slope like boulder deposit on the Table Cliffs Plateau, Utah, has moved slowly over a long period of time and has affected over 220 trees growing on it. Analyses of annual rings of trees affected by this and other slope movements show events such as inclination, shear, corrasion, burial, exposure, inundation, and nudation. Datable responses to these events are reaction-wood growth, growth suppression and release, ring termination and new callous growth, sprouting, succession, and miscellaneous structural and morphological changes. Various events may produce delayed, antagonistic, interfering, or irrelevant event responses, necessitating procedural caution. A modified skeleton plot of yearly event responses was constructed for each sample in this study with only strongly replicating dates from within trees considered valid. The resulting event-response curve shows peak periods of movement centered around the years 1781, 1803, 1827, 1849, 1869, 1885, 1890, 1907, 1910, 1923, 1938, 1942, 1944, and 1958. Spectral analysis of the event-response curve, mean annual precipitation, and an independently derived tree-ring precipitation surrogate suggests a possible relation between precipitation and slope movement. Analyses of temperature data did not produce results in spite of the presence of internal ice which might be expected to contribute to movement. Map plots of movement through time show event responses scattered in linear zones throughout the slope during main episodes of movement in any given move at different times and some parts move more than others.
Paleosol Sequences in the Eastern Cordillera of Colombia
Authors: Fölster H. , Hetsch W.
Published: July 2006

This paper presents paleosol chronosequences from the Eastern Cordillera of Colombia, covering the last 35,000 yr. The changes in the morphology of the soils which developed in successive layers of volcanic ash reflect climatic changes and are correlated to the palynological studies of Van Der Hammen. Middle Pleniglacial soils are regarded as gleyed (Polylepis) forest soils formed under low evapotranspiration, and soils of the Middle/Upper Pleniglacial transition as humiferous (grassland) Paramo soils. An intervening arid erosion phase was followed by a humid and warmer period (Holocene) during which humiferous soils developed partly under forest, partly under grassland, but throughout under conditions of higher evapotranspiration.
Distribution of Quartz in Late Quaternary Atlantic Sediments in Relation to Climate
Authors: Kolla Venkatarathnam , Biscaye Pierre E. , Hanley Adele F.
Published: July 2006

The distribution of quartz in the surface sediments of the Atlantic Ocean reflects derivation from continents by means of rivers, wind, ice, and coastal erosion. Enrichment of quartz thus supplied has occurred in some deep basins of especially the southern high latitudes from winnowing of finegrained clays by bottom currents. Although similar modes of quartz transport may have operated both during the Holocene and the last glacial maximum (18,000 yr B.P.), significant differences in the intensity of transport and in the locii of deposition, which are attributable to climatic variations during these times, exist in some areas of the Atlantic. In Holocene sediments of the eastern equatorial Atlantic, a band of high percent quartz exists directly off the present Saharan Desert and Sahel region and reflects the trade-wind transport of dusts from these arid and semiarid regions. During the last glacial maximum (18,000 yr B.P.), this high quartz band expanded southward by about 8° of latitude. This expansion was caused not only by the southward expansion of aridity and desert dunes but also by the southward migration of the northerly belt of trade winds during the last glaciation. Relatively high abundances and accumulation rates of quartz during the last glaciation suggest higher intensities of trade winds during that time compared to the Holocene. In the North Atlantic, the abundances of quartz in Holocene sediments are high adjacent to Greenland-Iceland and in the areas off Newfoundland-Labrador, and gradually decrease toward the central areas. The polar front and limit of sea-ice melting are at present confined to the northern part of the North Atlantic. The ice-rafting of quartz grains is, therefore, effective in the areas adjacent to Greenland and to some extent off Labrador causing high abundances in these areas. In contrast to this, during the last glaciation, the quartz abundances and accumulation rates are high in the central areas of North Atlantic around 45°N and decrease toward Greenland-Newfoundland. The migration of the polar front to as far south as 45°N and the consequent southward migration of sea-ice melting and ice-rafting during the last glaciation apparently caused this change in distribution. In addition to ice-rafting at present, wave or current reworking of relict glacial-marine detritus may have caused the high abundance of quartz in the surface sediments off Newfoundland-Labrador. In 18,000 yr B.P. sediments of the Norwegian Sea, the area of high percent quartz (>10%) is more extensive than that in Holocene sediments. This reflects the greater influence of ice-rafting or glacier activity in the sediment dispersal in the Norwegian Sea during the last glacial times.
An Equable Glaciopluvial in the West: Pleniglacial Evidence of Increased Precipitation on a Gradient from the Great Basin to the Sonoran and Chihuahuan Deserts
Authors: Wells Philip V.
Published: July 2006

Dated macrofossil evidence documents the widespread occurrence of woodland in what are now desert lowlands of southwestern North America from the last pleniglacial (ca. 20,000 yr B.P.) to late glacial/Holocene transition (12,000–8000 yr B.P.). The composition of the Pleistocene woodlands indicates that they had already differentiated geographically in modern form, though immensely more extensive than today. The pinyon-juniper woodland (Pinus monophylla, Juniperus osteosperma) of the Mohave Desert province had not yet penetrated the central Great Basin, but extended from southern Nevada south through the vast lowlands of the Mohave and westernmost Sonoran Deserts to southeastern California and Baja California. The strongly xerophytic Mohavean woodland was characterized by a very well-marked altitudinal and latitudinal zonation with juniper-Joshua tree (Yucca brevifolia) sorting out below pinyon-juniper woodland, and with live oaks restricted to the upper level along the lower Colorado River drainage. Southeastward, the Sonoran Desert province was similarly zoned, but with the more slender-leaved Pinus edulis var. fallax as pinyon and with more live oaks in the upper zone. However, the pleniglacial woodland of the Chihuahuan Desert province was almost unzoned, inasmuch as the less xerophytic species of pinyon and live oaks prevailed over the entire span of available elevation; the pinyon was the very slender-leaved P. cembroides var. remota.

The overall paleozonation indicates a strong northwest-to-southeast gradient of increasing summer rain with decreasing distance from the monsoonal source area over the Gulf of Mexico, as at present, but augmented pluvially along the same gradient. A key piece of evidence is the counterintuitive latitudinal-zonational anomaly between about 30 and 40° N in southwestern North America; the lower limits of modern vegetational zones are depressed with decreasing latitude (e.g., ca. 500 m lower at 34° than at 36° N). The axis of the gradient actually extends from northwest to southeast, paralleling the monsoonal gradient of increasing summer rain, which no doubt causes the apparent anomaly. During the Wisconsinan glacial, the latitudinal anomaly was greatly steepened, a fact requiring a pluvial increase in precipitation over the Southwest. The monsoonalpluvial pattern is supported by the Neotoma record of a northwest-to-southeast gradient of increasing diversity of evergreen oaks requiring summer rain, and by a parallel segregation of pinyon species. Equability of seasons during the last glacial is also suggested by the Neotoma macrofossil data.