CSULA Faculty Publicationshttp://hdl.handle.net/10211.3/1255622024-03-29T06:30:08Z2024-03-29T06:30:08ZRapid decadal convective precipitation increase over Eurasia during the last three decades of the 20th centuryYe, HengchunFetzer, Eric J.Wong, SunLambrigtsen, Bjorn H.http://hdl.handle.net/10211.3/1897552017-04-13T21:45:02Z2017-01-25T00:00:00ZRapid decadal convective precipitation increase over Eurasia during the last three decades of the 20th century
Ye, Hengchun; Fetzer, Eric J.; Wong, Sun; Lambrigtsen, Bjorn H.
Convective precipitation—localized, short-lived, intense, and sometimes violent—is at the root of challenges associated with observation, simulation, and prediction of precipitation. The understanding of long-term changes in convective precipitation characteristics and their role in precipitation extremes and intensity over extratropical regions are imperative to future water resource management; however, they have been studied very little. We show that annual convective precipitation total has been increasing astonishingly fast, at a rate of 18.4%/°C, of which 16% is attributable to an increase in convective precipitation occurrence, and 2.4% is attrib- utable to increased daily intensity based on the 35 years of two (combined) historical data sets of 3-hourly synoptic observations and daily precipitation. We also reveal that annual daily precipitation extreme has been increasing at a rate of about 7.4%/°C in convective events only. Concurrently, the overall increase in mean daily precipitation intensity is mostly due to increased convective precipitation, possibly at the expanse of noncon- vective precipitation. As a result, transitional seasons are becoming more summer-like as convective becomes the dominant precipitation type that has accompanied higher daily extremes and intensity since the late 1980s. The data also demonstrate that increasing convective precipitation and daily extremes appear to be directly linearly associated with higher atmospheric water vapor accompanying a warming climate over northern Eurasia.
2017-01-25T00:00:00ZAntimicrobial lipids: Emerging effector molecules of innate host defensePorter, Edith; Ma DC; Alvarez S; Faull KF.http://hdl.handle.net/10211.3/1476192015-10-30T22:24:26Z2015-07-27T00:00:00ZAntimicrobial lipids: Emerging effector molecules of innate host defense
Porter, Edith; Ma DC; Alvarez S; Faull KF.
The antimicrobial properties of host-derived derived
lipids have become increasingly recognized and
evidence is mounting
that antimicrobial lipids (AMLs),
like antimicrobial peptides, are effector molecules of
the innate immune system and are regulated by its
conserved pathways. This review, with primary focus
on the human body, provides some background on
the biochemistry of lipids, summarizes their biological
functions, expands on their antimicrobial properties and
site-specific composition, presents modes of synergism
with antimicrobial peptides, and highlights the more
recent reports on the regulation of AML production
as well as bacterial resistance mechanisms. Based on
extant data a concept of innate epithelial defense is
proposed where epithelial cells, in response to microbial
products and proinflammatory cytokines and through
activation of conserved innate signaling pathways,
increase their lipid uptake and up-regulate transcription
of enzymes involved in antimicrobial lipid biosynthesis,
and induce transcription of antimicrobial peptides as
well as cytokines and chemokines. The subsequently
secreted antimicrobial peptides and lipids then attack
and eliminate the invader, assisted by or in synergism
with other antimicrobial
molecules delivered by other
defense cells that have been recruited to the site of
infection, in most of the cases. This review invites accumulation in macrophage lipid droplets in response
to infection as a solely proinflammatory event, and
proposes a direct antimicrobial role of lipid dropletassociated
cholesteryl esters. Finally, for the interested,
but new- to- the-field investigator some starting points
for the characterization of AMLs are provided. Before it
is possible to utilize AMLs for anti-infectious therapeutic
and prophylactic approaches, we need to better
understand pathogen responses to these lipids and their
role in the pathogenesis
of chronic infectious disease.
2015-07-27T00:00:00ZUse of artificial neural networks for prediction of convective heat transfer in evaporative unitsPacheco-Vega, Arturohttp://hdl.handle.net/10211.3/1281952014-10-09T04:07:37Z2014-01-01T00:00:00ZUse of artificial neural networks for prediction of convective heat transfer in evaporative units
Pacheco-Vega, Arturo
Convective heat transfer prediction of evaporative processes is more complicated
than the heat transfer prediction of single-phase convective processes. This is due to the fact that physical phenomena involved in evaporative processes are very complex and vary with the vapor quality that increases gradually as more fluid is evaporated. Power-law correlations used for prediction of evaporative convection have proved little accuracy when used in practical cases. In this investigation, neural-network-based models have been used as a tool for prediction of the thermal performance of evaporative units. For this purpose, experimental data were obtained in a facility that includes a counter-flow concentric pipes heat exchanger with R134a refrigerant flowing inside the circular
section and temperature controlled warm water moving through the annular
section. This work also included the construction of an inverse Rankine refrigeration
cycle that was equipped with measurement devices, sensors and a data
acquisition system to collect the experimental measurements under different
operating conditions. Part of the data were used to train several neural-network
configurations. The best neural-network model was then used for prediction
purposes and the results obtained were compared with experimental data not
used for training purposes. The results obtained in this investigation reveal the
convenience of using artificial neural networks as accurate predictive tools for
determining convective heat transfer rates of evaporative processes.
2014-01-01T00:00:00ZWhen do words promote analogical transfer?Son, Jihttp://hdl.handle.net/10211.3/1281892014-10-09T04:07:39Z2010-01-01T00:00:00ZWhen do words promote analogical transfer?
Son, Ji
The purpose of this paper is to explore how and when verbal labels facilitate relational
reasoning and transfer. We review the research and theory behind two ways words might
direct attention to relational information: (1) words generically invite people to compare
and thus highlight relations (the Generic Tokens [GT] hypothesis), and/or (2) words carry
semantic cues to common structure (the Cues to Specific Meaning [CSM] hypothesis). Four experiments examined whether learning Signal Detection Theory (SDT) with relational words fostered better transfer than learning without relational words in easily alignable and less alignable situations (testing the GT hypothesis) as well as when the relational words matched and mismatched the semantics of the learning situation (testing the CSM hypothesis). The results of the experiments found support for the GT hypothesis because the presence of relational labels produced better transfer when two situations were alignable. Although the CSM hypothesis does not explain how words facilitate transfer, we found that mismatches between words and their labeled referents can produce a situation where words hinder relational learning.
2010-01-01T00:00:00Z