Paleovegetation and Paleoclimate in the Past 20,000 Years in Jiaozhou Bay,Qingdao District

The spore-pollen assemblages collected from drilling cores in Jiaozhou Bay, Qingdao district, are analyzed in this paper. We have ascertained paleovegetation and paleodimate since last 20000 years in the studied district. It is concluded that development process can be devided into six stages, each stage has its corresponding characteristics on paleovegetation and paleoclimate. These stages are listed as follows: ( 1 ) Vegetation was mainly herbaceous plants and climate was cold and dry during 20000–13000 years B P (2) During 13000– 11000 years B P, there was a little conifer forest and herbaceous plants, in which aquatic and weter plants were relatively richer in quantities, climate was mild and wet. (3) During 11000–8500 years B P there was a little conifer and broadleaved forest and herbaceous plants, climate was mild and slightly dry. (4)During 8500–5000 years B P broadleaved trees were predominant but mixed with conifer forest, climate was warm and wet. (5) During 5000–2500 years B P conifer trees were predominant but mixed with broadleaved trees and herbaceous plants, climate was mild and slightly dry. (6) From 2300 years B P to present, we can further divide this stage into two periods, the preceding period and the late period. In the preceding period, vegetation was composed by conifer and broadleaved trees and herbaceous plants, climate was warm and wet; while conifer trees (including a little broadleaved trees) were prevailed in the late period, climate was mild and wet. As a result, we have concluded that the general tendency of climate variation for the studied district is consistent with North China and East China one, but there still exists a little differences. The authors suggest that the time limit between Pleistocene and Holocene should be demarcated at 11000 years B P owing to sharply increasing temperature for the studied district.     

The Time Course of Corticospinal Excitability during a Simple Reaction Time Task

The production of movement in a simple reaction time task can be separated into two time periods: the foreperiod, which is thought to include preparatory processes, and the reaction time interval, which includes initiation processes. To better understand these processes, transcranial magnetic stimulation has been used to probe corticospinal excitability at various time points during response preparation and initiation. Previous research has shown that excitability decreases prior to the “go” stimulus and increases following the “go”; however these two time frames have been examined independently. The purpose of this study was to measure changes in CE during both the foreperiod and reaction time interval in a single experiment, relative to a resting baseline level. Participants performed a button press movement in a simple reaction time task and excitability was measured during rest, the foreperiod, and the reaction time interval. Results indicated that during the foreperiod, excitability levels quickly increased from baseline with the presentation of the warning signal, followed by a period of stable excitability leading up to the “go” signal, and finally a rapid increase in excitability during the reaction time interval. This excitability time course is consistent with neural activation models that describe movement preparation and response initiation.     

Paleovegetation and paleoclimate in middle-late Pliocene, Shanxi, central China

Sequences of lacustrine sediments developed in intermontane basins in the middle-eastern Shanxi Plateau of China have been investigated in order to reconstruct the paleovegetation and paleoclimate for the middle-late Pliocene. According to the magnetostratigraphy and the fossil assemblages, the lacustrine sediments of Yushe and Taigu Basins were deposited between 5.5 and 2.5 Ma BP. The Zhangcun and Xiaobai Formations are considered to cover a similar period, ranging from 3.5 to 2.5 Ma BP. An increase of Picea and Abies shows that the climate began to become cold after about 4.4 Ma BP. A cold-wet episode, with relatively warm-dry and warm-humid intervals, occurred between 3.6 and 2.5 Ma BP in the Yushe and Taigu Basins. An increase Artemisia, Chenopodiaceae and Ephedra shows that the climate became drier after 2.5 Ma BP. The climate changes of this period probably reflect variations of the East Asian winter and summer monsoons, with an increase winter monsoon activity during the early Pleistocene.     

Paleoclimate during Neandertal and anatomically modern human occupation at Amud and Qafzeh, Israel: the stable isotope data

The δ¹³C(en) and δ¹⁸O(en) values of goat and gazelle enamel carbonate indicate that Neandertals at Amud Cave, Israel (53-70 ka) lived under different ecological conditions than did anatomically modern humans at Qafzeh Cave, Israel (approximately 92 ka). During the Last Glacial Period, Neandertals at Amud Cave lived under wetter conditions than those in the region today. Neither faunal species ate arid-adapted C₄ plants or drought-stressed C₃ plants. The variation in gazelle δ¹⁸O(en) values suggests multiple birth seasons, which today occur under wetter than normal conditions. The magnitude and pattern of intra-tooth variation in goat δ¹⁸O(en) values indicate that rain fell throughout the year unlike today.Anatomically modern humans encountered a Qafzeh Cave region that was more open and arid than Glacial Period Amud Cave, and more open than today's Upper Galilee region. Goat δ¹³C(en) values indicate feeding on varying amounts of C₄ plants throughout the year. The climate apparently ameliorated higher in the sequence; but habitats remained more open than at Amud Cave. Both gazelles and goats fed on C₃ plants in brushy habitats without any inclusion of C₄ plants. The magnitude of intra-tooth variation in goat δ¹⁸O(en) values, however, suggest that some rain fell throughout the year, and the relative representation of woodland dwelling species indicates the occurrence of woodlands in the region.Climate differences affecting the distribution of plants and animals appear to be the significant factor contributing to behavioral differences previously documented between Neandertals and anatomically modern humans in the region. Climate forcing probably affected the early appearances of anatomically modern humans, although not the disappearance of Neandertals from the Levant.     

Paleoclimate and Evolution, with Emphasis on Human Origins

Paleoclimate and Evolution, with Emphasis on Human Origins. Elisabeth S. Vrba. George H. Denton. Timothy C. Partridge. and Lloyd H. Burckle. eds. New Haven, CT: Yale University Press, 1995. 547 pp.     

上海青浦8.5kaB.P.以来植被演变与气候波动

钻孔取自上海青浦县赵巷镇,柱长19.8m,5个14C年龄(AMS测定)年代跨度从13460±60aB.P.到2660±60aB.P,但缺失全新世早期沉积。对15m以上(8.5aB.P.)部分系统采集了35孢粉样品,样品分辩率在150a左右(少数样品除外);通过有序分割并综合图谱特征划分出7个孢粉带和2个亚带,据此恢复和重建了本区8.5kaB.P以来植被变化和气候波动历史。具体结果为与现今气候相比,8.5aB.P.～8.2kaB.P.为冷干期,但气候呈上升趋势,地带性植被为含常绿阔叶树种的落叶阔叶林;8.2kaB.P.～8.0kaB.P.为暖湿期、常绿阔叶林,气候处于峰值,温度高于现今2℃左右,降雨量高于现今400mm左右;8.0kaB.P.～7.6kaB.P.为冷干期、落叶阔叶和针阔混交林,气候处于谷值,温度低于现今2℃左右,降雨量少于现今400mm左右;7.6kaB.P.～6.2kaB.P.为暖湿期、常绿阔叶林或常绿、落叶阔叶混交林;6.2kaB.P.～4.0kaB.P.为温干期、含常绿阔叶树种的落叶林或针阔混交林;4.0kaB.P.～3.0kaB.P.为温凉略湿期、含常绿阔叶的落叶阔叶林;3.0kaB.P.～1.5kaB.P.为暖湿期、常绿阔叶林,但2.6kaB.P.以来又有变冷趋势。 文中还对常绿阔叶木本孢粉与总木本孢粉的比值(E/W)的生态意义进行了讨论。     

Negative Emotional Events that People Ruminate about Feel Closer in Time

Rumination is intrusive, perseverative cognition. We suggest that onepsychological consequence of ruminating about negative emotional events is thatthe events feel as though they happened metaphorically “justyesterday”. Results from three studies showed that ruminating about realworld anger provocations, guilt-inducing events, and sad times in the last yearmade these past events feel as though they happened more recently. Therelationship between rumination and reduced temporal psychological distancepersisted even when controlling for when the event occurred and the emotionalintensity of the event. Moreover, angry rumination was correlated with enhancedapproach motivation, which mediated the rumination-distance relationship. Therelationship between guilty rumination and distance was mediated by enhancedvividness. Construal level and taking a 3^rd person perspectivecontributed to the sense of distance when participants were prompted to thinkabout less emotionally charged situations. A meta-analysis of the data showedthat the relationship between rumination and reduced distance was significantand twice as large as the same relationship for neutral events. These findingshave implications for understanding the role of emotional rumination on memoryprocesses in clinical populations and people prone to rumination. This researchsuggests that rumination may be a critical mechanism that keeps negative eventsclose in the heart, mind, and time.     

The Time Course of Activation of Object Shape and Shape+Colour Representations during Memory Retrieval

Little is known about the timing of activating memory for objects and their associated perceptual properties, such as colour, and yet this is important for theories of human cognition. We investigated the time course associated with early cognitive processes related to the activation of object shape and object shape+colour representations respectively, during memory retrieval as assessed by repetition priming in an event-related potential (ERP) study. The main findings were as follows: (1) we identified a unique early modulation of mean ERP amplitude during the N1 that was associated with the activation of object shape independently of colour; (2) we also found a subsequent early P2 modulation of mean amplitude over the same electrode clusters associated with the activation of object shape+colour representations; (3) these findings were apparent across both familiar (i.e., correctly coloured – yellow banana) and novel (i.e., incorrectly coloured - blue strawberry) objects; and (4) neither of the modulations of mean ERP amplitude were evident during the P3. Together the findings delineate the timing of object shape and colour memory systems and support the notion that perceptual representations of object shape mediate the retrieval of temporary shape+colour representations for familiar and novel objects.     

Rising Obesity-Related Hospital Admissions among Children and Young People in England: National Time Trends Study

Objective

To describe the trends in hospital admissions associated with obesity as a primary diagnosis and comorbidity, and bariatric surgery procedures among children and young people in England.

Design

National time trends study of hospital admissions data between 2000 and 2009.

Participants

Children and young people aged 5 to 19 years who were admitted to hospital with any diagnosis of obesity.

Main outcome measures

Age- and sex-specific admission rates per million children.

Results

Between 2000 and 2009, age- and sex-specific hospital admission rates in 5–19 year olds for total obesity-related diagnoses increased more than four-fold from 93.0 (95% CI 86.0 to 100.0) per million children to 414.0 (95% CI 410.7 to 417.5) per million children, largely due to rising admissions where obesity was mentioned as a co-morbidity. The median age of admission to hospital over the study period was 14.0 years; 5,566 (26.7%) admissions were for obesity and 15,319 (73.3%) mentioned obesity as a comorbidity. Admissions were more common in girls than boys (56.2% v 43.8%). The most common reasons for admission where obesity was a comorbid condition were sleep apnoea, asthma, and complications of pregnancy. The number of bariatric surgery procedures has risen from 1 per year in 2000 to 31 in 2009, with the majority were performed in obese girls (75.6%) aged 13–19 years.

Conclusions

Hospital admission rates for obesity and related comorbid conditions have increased more than four-fold over the past decade amongst children and young people. Although some of the increase is likely to be due to improved case ascertainment, conditions associated with obesity in children and young people are imposing greater challenges for health care providers in English hospitals. Most inpatient care is directed at dealing with associated conditions rather than primary assessment and management of obesity itself.