scholarly journals A new positive relationship between pCO2 and stomatal frequency in Quercus guyavifolia (Fagaceae): a potential proxy for palaeo-CO2 levels

2015 ◽  
Vol 115 (5) ◽  
pp. 777-788 ◽  
Author(s):  
Jin-Jin Hu ◽  
Yao-Wu Xing ◽  
Roy Turkington ◽  
Frédéric M. B. Jacques ◽  
Tao Su ◽  
...  
2019 ◽  
Vol 123 (7) ◽  
pp. 1147-1158 ◽  
Author(s):  
Jin-Jin Hu ◽  
Yao-Wu Xing ◽  
Tao Su ◽  
Yong-Jiang Huang ◽  
Zhe-Kun Zhou

AbstractBackground and AimsThe inverse correlation between atmospheric CO2 partial pressure (pCO2) and stomatal frequency in many plants has been widely used to estimate palaeo-CO2 levels. However, apparent discrepancies exist among the obtained estimates. This study attempts to find a potential proxy for palaeo-CO2 concentrations by analysing the stomatal frequency of Quercus glauca (section Cyclobalanopsis, Fagaceae), a dominant species in East Asian sub-tropical forests with abundant fossil relatives.MethodsStomatal frequencies of Q. glauca from three material sources were analysed: seedlings grown in four climatic chambers with elevated CO2 ranging from 400 to 1300 ppm; extant samples collected from 14 field sites at altitudes ranging from 142 to 1555 m; and 18 herbarium specimens collected between 1930 and 2011. Stomatal frequency–pCO2 correlations were determined using samples from these three sources.Key ResultsAn inverse correlation between stomatal frequency and pCO2 was found for Q. glauca through cross-validation of the three material sources. The combined calibration curves integrating data of extant altitudinal samples and historical herbarium specimens improved the reliability and accuracy of the curves. However, materials in the climatic chambers exhibited a weak response and relatively high stomatal frequency possibly due to insufficient treatment time.ConclusionsA new inverse stomatal frequency–pCO2 correlation for Q. glauca was determined using samples from three sources. These three material types show the same response, indicating that Q. glauca is sensitive to atmospheric pCO2 and is an ideal proxy for palaeo-CO2 levels. Quercus glauca is a nearest living relative (NLR) of section Cyclobalanopsis fossils, which are widely distributed in the strata of East Asia ranging from the Eocene to Pliocene, thereby providing excellent materials to reconstruct the atmospheric CO2 concentration history of the Cenozoic. Quercus glauca will add to the variety of proxies that can be widely used in addition to Ginkgo and Metasequoia.


2002 ◽  
Vol 61 (3) ◽  
pp. 139-151 ◽  
Author(s):  
Céline Darnon ◽  
Céline Buchs ◽  
Fabrizio Butera

When interacting on a learning task, which is typical of several academic situations, individuals may experience two different motives: Understanding the problem, or showing their competences. When a conflict (confrontation of divergent propositions) emerges from this interaction, it can be solved either in an epistemic way (focused on the task) or in a relational way (focused on the social comparison of competences). The latter is believed to be detrimental for learning. Moreover, research on cooperative learning shows that when they share identical information, partners are led to compare to each other, and are less encouraged to cooperate than when they share complementary information. An epistemic vs. relational conflict vs. no conflict was provoked in dyads composed by a participant and a confederate, working either on identical or on complementary information (N = 122). Results showed that, if relational and epistemic conflicts both entailed more perceived interactions and divergence than the control group, only relational conflict entailed more perceived comparison activities and a less positive relationship than the control group. Epistemic conflict resulted in a more positive perceived relationship than the control group. As far as performance is concerned, relational conflict led to a worse learning than epistemic conflict, and - after a delay - than the control group. An interaction between the two variables on delayed performance showed that epistemic and relational conflicts were different only when working with complementary information. This study shows the importance of the quality of relationship when sharing information during cooperative learning, a crucial factor to be taken into account when planning educational settings at the university.


2016 ◽  
Vol 27 (4) ◽  
pp. 257-264 ◽  
Author(s):  
Johannes H. Scheidemann ◽  
Franz Petermann ◽  
Marc Schipper

Abstract. We investigated theory of mind (ToM) deficits in Alzheimer‘s disease (AD) and its possible connection to autobiographical memory (ABM). Patients and matched controls were evaluated and compared using a video-based ToM test, an autobiographical fluency task, and a neuropsychological test battery. We found that ToM deficits were positively associated with semantic ABM in the clinical group, whereas a positive relationship appeared between ToM and episodic ABM in controls. We hypothesize that this reflects the course of the disease as well as that semantic ABM is used for ToM processing, being still accessible in AD. Furthermore, we assume that it is also less efficient, which in turn leads to a specific deficit profile of social cognition.


2004 ◽  
Vol 20 (4) ◽  
pp. 237-246 ◽  
Author(s):  
G. Van Humbeeck ◽  
Ch. Van Audenhove ◽  
G. Storms ◽  
M. De Hert ◽  
G. Pieters ◽  
...  

Summary: Background: This article reports on a study of the concurrent validity between the standard expressed emotion instrument, the Camberwell Family Interview (CFI), and two alternative EE measures, the Level of Expressed Emotion (LEE) and the Perceived Criticism Scale (PCS). Methods: The research sample consisted of 56 schizophrenic clients, who were residing in sheltered residences, and 56 professionals. Results: Based on the results of the correlation matrix between all the subscales of the instruments, a significantly positive relationship was found between the criticism scale of the CFI, the total score of the LEE, and the client version of the PCS. These correlations, however, were rather weak, which implies that the three instruments have little in common with each other. The professionals' version of the PCS does not appear to be an EE instrument. Conclusions: The results suggest that the CFI still remains the best instrument for assessing EE in a therapeutic relationship (between a professional and a client). If there is insufficient time to administer the CFI, then the client version of the PCS and the LEE can be used with the qualification that the PCS and LEE also measure other aspects and thus cannot completely replace the CFI. Nevertheless, the research indicates that asking the clients would seem to provide a better indication of the level of the professionals' criticism rather than asking the professionals themselves directly.


2006 ◽  
Author(s):  
Heather Setrakian ◽  
Gian Gonzaga ◽  
Lynette Lau ◽  
Gazi Begum ◽  
Thomas Bradbury

2014 ◽  
Vol 1 (1) ◽  
pp. 47-56
Author(s):  
Milan Palat

Bu çalışmanın amacı, Türkiye’den göç ve Almanya’nın ekonomik göstergeleri arasındaki ilişkiyi, nicel metot yöntemleri kullanarak değerlendirmektir. Türkiye’nin belirsiz Avrupa ile bütünleşme beklentilerine rağmen  Avrupa Birliğinin köklü üyelerine olan Türk göçü devam edecektir. Çok sayıda Türk azınlığın yaşadığı ve hayat standartlarının yüksek olduğu Almanya, Hollanda ve Fransa’ya  büyük bir göç dalgası gerçekleşebilir. Çalışmanın istatistiksel bölümünün sonuçları, toplam göç ile gayri safi yurtiçi hasıladaki büyüme arasında pozitif, toplam göç ile işsizlik arasındaki negatif ve tahmin edilen bağımlılık yönüyle uygunluk içerisinde olan toplam göç ile aylık gelir arasında pozitif ilişki olduğunu göstermektedir. Türkiye’den göçle işsizlik arasındaki ilişki, toplam göçle olan ilişkiden daha düşüktür. Ancak, Almanya’daki yabancı mevcudiyeti ile Türkiye’den göç arasında bir ilişki bulunmaktadır. Bu durum, var olan göçmen topluluğunun olduğu yerin, yeni göçmenleri, köken bağlarına dayanarak cezbetmesi ve maliyet- riskler sebebiyle göçün düşük seviye de olduğuna dayanan kuramsal Ağ teorisi görüşü ile uygunluk göstermektedir. Göç ve işsizlik arasında gözlenen ilişki, Almanya’ya göçün  işgücü piyasasında talepte meydana gelen değişime karşılık geldiği gerçeğini göstermektedir. İşsizlik ve göç olgularının meydana geliş zamanlarında bir aralık  olsa bile  göç, Alman emek pazarında var olan dengesizliklerin azaltılmasında nispeten etkili bir mekanizma gibi görünmektedir. ENGLISH TITLE & ABSTRACTTurkish Immigration to the European Union: The Case of GermanyThe objective of the paper was to evaluate the relationships between immigration from Turkey and economic indicators in Germany using  quantitative methods. Despite Turkey’s unclear European integration prospects, it is predicted that Turkish immigration to  established member countries of the EU will continue. The strongest waves may flow to Germany, Netherlands or France, where numerous Turkish minorities are already present and where the living standards are high. Results from the statistical analysis of the paper showed a positive correlation between immigration total and the growth of gross domestic product. On the other hand, a negative correlation of immigration total and unemployment was found and a positive relationship between immigration total and income total which is in agreement with the expected dependency direction. With regards to  immigration from Turkey it is less correlated to unemployment than immigration total. But there is a correlation between immigration from Turkey and the stock of foreigners in Germany This is in accordance with the theoretical concept of network theory where an existing community of migrants keeps attracting new migrants because the costs and risks associated with migration are lower, thanks to established linkages to the country of origin. The observed correlation of migration and unemployment points to the fact that immigration to Germany responds to changes in demand in the labour market. Even though a time lag may occur in the case of unemployment and immigration, migration appears to be a relatively effective mechanism to offset existing imbalances in German labour markets. 


2018 ◽  
Vol 9 (6) ◽  
pp. 529-536
Author(s):  
Martin Khoya Odipo ◽  

Recent studies have documented that innovations improve profitability of firms. This article documents that deposit taking micro financial institutions that have adopted financial innovations have increased their profitability. The study covered five years between 2009-2013. Both primary and secondary data were used in the study. Primary data was obtained through administration of drop and pick questionnaires to selected employees of the institutions. Secondary data was obtained from financial statements and management reports of these deposit taking microfinance institutions. Data was analyzed using descriptive statistics, return on asset and multi-liner regression model to determine the effect of each financial innovation applied on profitability on the micro-financial institution. The results showed that most deposit taking microfinance institutions adopted these financial innovations in their current operations. There was strong positive relationship between individual innovations and profitability. In line with profitability ROA also showed improvement each year after the adoption of these financial innovations.


2014 ◽  
Vol 2 (1) ◽  
Author(s):  
Dr. Thiyam Kiran Singh ◽  
Aastha Dhingra

Love is more than a close friendship. It acts as a major facilitator of interpersonal relationship. Love is positive in nature and leaves a positive affect on every individual. An individual in love not only feels positive but spreads positivity around. They smile, be kind to other people, behave compassionately with everyone. If the person is happy then he is likely to be psychologically and emotionally healthy. The current study aimed at understanding the relationship between love, affect and wellbeing among young females aged between 20-25 years. The study reported a significant positive relationship between love and positive affect with the significant correlation of 0.29 at 0.05 levels (p<0.05). It was also found a significant positive relationship between love and wellbeing with the significant correlation of 0.58 at 0.01 level (p<0.01). This means that people in love experience positive emotions and healthy wellbeing. The correlation between love and negative affect came out to be insignificant. The correlation turned out to be -0.13. This means that people in love do not experience negative emotions.


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