A Case Study of Mesoscale Snowfall Development Associated with Tropopause Folding

This research aims to investigate the dynamic of static stability (N2), potential energy of gravity waves (Ep), and vortex in the stratospheric northern hemisphere during 2012-2013 winter using temperature (T) and zonal wind (u) data from NCEP-DOE Reanalysis II. The results showed two occurrences of decreasing N2 ascociated with reversal of u in the first and third week of December 2012 were believed as a trigger of Sudden Stratospheric Warmings (SSW) on January 7, 2013. There was a flow from the polar to the tropics region during the SSW event. It caused the tropopause folding in the sub-tropic region indicated by the distribution of Ep on January 24, 2013. This tropopause folding triggered the convective activity over the Indonesian continents as shown by the negative OLR anomaly from 22 to 26 January 2013. The impact of SSW event in the northern hemisphere to the convective activity was 20%. This results showed the interaction between stratosphere and troposphere and also the teleconnection between the polar and the tropics. ABSTRAKPenelitian ini bertujuan menyelidiki dinamika stabilitas statis (N2), energi potensial gelombang gravitas (Ep), dan pusaran angin di lapisan stratosfer Belahan Bumi Utara (BBU) selama musim dingin 2012-2013 menggunakan data temperatur (T) dan komponen angin zonal (u) dari NCEP-DOE Reanalysis II. Hasil riset menunjukkan bahwa dua kejadian penurunan N2 pada pekan awal dan ketiga bulan Desember 2012 diyakini sebagai pemicu kejadian Sudden Stratosphere Warmings (SSW) tanggal 7 Januari 2013. Pada saat terjadi SSW terdapat aliran dari kutub menuju tropis. Aliran ini mengakibatkan terjadinya pelipatan lapisan tropopause di wilayah sub-tropis yang terlihat pada distribusi Ep tanggal 24 Januari 2013. Pelipatan lapisan tropopause ini kemudian memicu aktivitas konvektif di atas wilayah Indonesia yang ditandai oleh anomali OLR negatif antara tanggal 22-26 Januari 2013. Dampak kejadian SSW di BBU terhadap aktivitas konvektif di atas wilayah kepulauan Indonesia sebesar 20%. Hasil ini membuktikan interaksi antara lapisan stratosfer dan troposfer serta telekoneksi wilayah kutub dan tropis.

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The Genesis and Internal Dynamics of El Salvador's People's Revolutionary Army, 1970–1976

Behavioral and Brain Sciences ◽

10.1017/s0140525x13009850 ◽

2014 ◽

Vol 38 (01) ◽

pp. 102-129

Author(s):

ALBERTO MARTÍN ÁLVAREZ ◽

EUDALD CORTINA ORERO

Keyword(s):

Latin America ◽

El Salvador ◽

Early Years ◽

Left Wing ◽

Internal Dynamics ◽

Internal Coherence ◽

The 1960S

AbstractUsing interviews with former militants and previously unpublished documents, this article traces the genesis and internal dynamics of the Ejército Revolucionario del Pueblo (People's Revolutionary Army, ERP) in El Salvador during the early years of its existence (1970–6). This period was marked by the inability of the ERP to maintain internal coherence or any consensus on revolutionary strategy, which led to a series of splits and internal fights over control of the organisation. The evidence marshalled in this case study sheds new light on the origins of the armed Salvadorean Left and thus contributes to a wider understanding of the processes of formation and internal dynamics of armed left-wing groups that emerged from the 1960s onwards in Latin America.

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Culture and the plasticity of perception

Behavioral and Brain Sciences ◽

10.1017/s0140525x19002887 ◽

2020 ◽

Vol 43 ◽

Author(s):

Michael Lifshitz ◽

T. M. Luhrmann

Keyword(s):

Cultural Context ◽

Sensory Experience ◽

Cultural Learning ◽

The World

Abstract Culture shapes our basic sensory experience of the world. This is particularly striking in the study of religion and psychosis, where we and others have shown that cultural context determines both the structure and content of hallucination-like events. The cultural shaping of hallucinations may provide a rich case-study for linking cultural learning with emerging prediction-based models of perception.

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Dual systems for all: Higher-order, role-based relational reasoning as a uniquely derived feature of human cognition

Behavioral and Brain Sciences ◽

10.1017/s0140525x19000451 ◽

2019 ◽

Vol 42 ◽

Author(s):

Daniel J. Povinelli ◽

Gabrielle C. Glorioso ◽

Shannon L. Kuznar ◽

Mateja Pavlic

Keyword(s):

Temporal Reasoning ◽

Higher Order ◽

Important Case ◽

Human Cognition ◽

Relational Reasoning ◽

Dual Systems ◽

First Order ◽

Reasoning System ◽

Role Based

Abstract Hoerl and McCormack demonstrate that although animals possess a sophisticated temporal updating system, there is no evidence that they also possess a temporal reasoning system. This important case study is directly related to the broader claim that although animals are manifestly capable of first-order (perceptually-based) relational reasoning, they lack the capacity for higher-order, role-based relational reasoning. We argue this distinction applies to all domains of cognition.

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Sociocultural memory development research drives new directions in gadgetry science

Behavioral and Brain Sciences ◽

10.1017/s0140525x19000979 ◽

2019 ◽

Vol 42 ◽

Author(s):

Penny Van Bergen ◽

John Sutton

Keyword(s):

Episodic Memory ◽

Autobiographical Memory ◽

Developmental Psychology ◽

Cross Cultural ◽

Memory Development ◽

Development Research ◽

Cultural Research ◽

New Directions ◽

Cross Cultural Research

Abstract Sociocultural developmental psychology can drive new directions in gadgetry science. We use autobiographical memory, a compound capacity incorporating episodic memory, as a case study. Autobiographical memory emerges late in development, supported by interactions with parents. Intervention research highlights the causal influence of these interactions, whereas cross-cultural research demonstrates culturally determined diversity. Different patterns of inheritance are discussed.

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Construction of plastic contact deformation maps on ceramics: a case study on aluminum nitride

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100165641 ◽

1996 ◽

Vol 54 ◽

pp. 636-637

Author(s):

D. L. Callahan

Keyword(s):

Plastic Deformation ◽

Aluminum Nitride ◽

Mechanical Response ◽

Three Dimensional ◽

Bright Field Image ◽

Perfectly Plastic ◽

Contrast Analysis ◽

Deformation Patterns

Modern polishing, precision machining and microindentation techniques allow the processing and mechanical characterization of ceramics at nanometric scales and within entirely plastic deformation regimes. The mechanical response of most ceramics to such highly constrained contact is not predictable from macroscopic properties and the microstructural deformation patterns have proven difficult to characterize by the application of any individual technique. In this study, TEM techniques of contrast analysis and CBED are combined with stereographic analysis to construct a three-dimensional microstructure deformation map of the surface of a perfectly plastic microindentation on macroscopically brittle aluminum nitride.The bright field image in Figure 1 shows a lg Vickers microindentation contained within a single AlN grain far from any boundaries. High densities of dislocations are evident, particularly near facet edges but are not individually resolvable. The prominent bend contours also indicate the severity of plastic deformation. Figure 2 is a selected area diffraction pattern covering the entire indentation area.

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