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Unsupervised learning on scientific ocean drilling datasets from the south china sea

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Frontiers of Earth science 2019年第1期13卷 180-190页

作者： Kevin c.TsE Hon-chim cHIU Man-Yin TsANG Yiliang LI Edmund Y.lam Department of Earth sciences The University of Hong KongPokfulamHong KongChina Department of Geography and centre for Geo-computation studies Hong Kong Baptist UniversityKowloon TongHong KongChina Department of Earth sciences University of TorontoTorontoON M5S 2M8Canada Department of Electrical and Electronic Engineering The University of Hong KongPokfulamHong KongChina

Unsupervised learning methods were applied to explore data patterns in multivariate geophysical datasets collected from ocean floor sediment core samples coming from scientific ocean drilling in the south china *** to studies on similar datasets,but using supervised learning methods which are designed to make predictions based on sample training data,unsupervised learning methods require no a priori information and focus only on the input *** this study,popular unsupervised learning methods including K-means,self-organizing maps,hierarchical clustering and random forest were coupled with different distance metrics to form exploratory data *** resulting data clusters were externally validated with lithologic units and geologic time scales assigned to the datasets by conventional methods. compact and connected data clusters displayed varying degrees of correspondence with existing classification by lithologic units and geologic time scales.K-means and self-organizing maps were observed to perform better with lithologic units while random forest corresponded best with geologic time *** study sets a pioneering example of how unsupervised machine learning methods can be used as an automatic processing tool for the increasingly high volume of scientific ocean drilling data.

关键词： machine learning unsupervised learning ODP IODP clustering

salt Tolerance in soybean

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Journal of Integrative Plant Biology 2008年第10期50卷 1196-1212页

作者： Tsui-Hung Phang Hon-Ming lam Department of Biology The Chinese University of Hong KongShatinHong Kong China state Key Laboratory for Agrobiotechnology The Chinese University of Hong KongShatinHong Kong China

soybean is an important cash crop and its productivity is significantly hampered by salt stress. High salt imposes negative impacts on growth, nodulation, agronomy traits, seed quality and quantity, and thus reduces the yield of soybean. To cope with salt stress, soybean has developed several tolerance mechanisms, including：（i） maintenance of ion homeostasis; （ii） adjustment in response to osmotic stress; （iii） restoration of osmotic balance; and （iv） other metabolic and structural adaptations. The regulatory network for abiotic stress responses in higher plants has been studied extensively in model plants such as Arabidopsis thaliana. some homologous components involved in salt stress responses have been identified in soybean. In this review, we tried to integrate the relevant works on soybean and proposes a working model to describe its salt stress responses at the molecular level.

关键词： abiotic stress Glycine max ion homeostasis osmotic adjustment reactive oxygen species scavenging salt tolerance soybean.

Emerging roles and therapeutic potentials of sphingolipids in pathophysiology:emphasis on fatty acyl heterogeneity

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Journal of Genetics and Genomics 2024年第3期51卷 268-278页

作者： Jinming Mu sin Man lam Guanghou shui state Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China University of chinese Academy of sciences Beijing 100101China Lipidall Technologies company Limited ChangzhouJiangsu 213000China

sphingolipids not only exert structural roles in cellular membranes,but also act as signaling molecules in various physiological and pathological processes.A myriad of studies have shown that abnormal levels of sphingolipids and their metabolic enzymes are associated with a variety of human ***,blood sphingolipids can also be used as biomarkers for disease *** review summarizes the biosynthesis,metabolism,and pathological roles of sphingolipids,with emphasis on the biosynthesis of ceramide,the precursor for the biosynthesis of complex sphingolipids with different fatty acyl *** possibility of using sphingolipids for disease prediction,diagnosis,and treatment is also *** endogenous ceramides and complex sphingolipids along with their specific fatty acyl chain to promote future drug development will also be discussed.

关键词： sphingolipids ceramide Therapeutic targets Microdomain Biomarker

Analysis of the inflection points of height-diameter models

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Forest Ecosystems 2024年第4期11卷 414-422页

作者： Tzeng Yih lam Mark J.Ducey Department of Forest Resources Management Faculty of ForestryThe University of British Columbia2045-2424 Main MallVancouverBCV6T 1Z4 Canada Department of Natural Resources and the Environment University of New Hampshire114 James HallDurhamNH 03824USA

The inflection point is an important feature of sigmoidal height-diameter(H-D)*** is often cited as one of the properties favoring sigmoidal model ***,there are very few studies analyzing the inflection points of H-D *** goals of this study were to theoretically and empirically examine the behaviors of inflection points of six common H-D models with a regional *** six models were the Wykoff(WYK),schumacher(scH),curtis(cUR),HossfeldⅣ(HOs),von Bertalanffy-Richards(VBR),and Gompertz(GPZ)*** models were first fitted in their base forms with tree species as random effects and were then expanded to include functional traits and spatial *** distributions of the estimated inflection points were similar between the two-parameter models WYK,scH,and cUR,but were different between the threeparameter models HOs,VBR,and *** produced some of the largest inflection *** and VBR produced concave H-D curves without inflection points for 12.7%and 39.7%of the tree *** species or decreasing shade tolerance resulted in larger inflection *** trends in the estimated inflection points of HOs and VBR were entirely opposite across the ***,HOs could produce concave H-D curves for portions of the *** on the studied behaviors,the choice between two-parameter models may not *** recommend comparing seve ral three-parameter model forms for consistency in estimated inflection points before deciding on *** sigmoidal models to have inflection points does not necessarily mean that they will produce fitted curves with *** study highlights the need to integrate analysis of inflection points into modeling H-D relationships.

关键词： concavity Forest inventory and analysis Generalized height-diameter models Growth functions Height-diameter functions Mixed-effects modeling Points of inflection species-specific models

Disease progression after discontinuation of corticosteroid treatment in a cOVID-19 patient with ARDs

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Asian Pacific Journal of Tropical Medicine 2022年第1期15卷 47-48页

作者： lam Nguyen-Ho Department of Internal Medicine University of Medicine and Pharmacy at Ho Chi Minh CityVietnam University Medical center HcMc Ho Chi Minh CityVietnam

Excessive acute inflammatory response in coronavirus-induced disease 2019(cOVID-19)patients results in multiple organ injury,especially acute respiratory distress syndrome(ARDs),contributing to a high mortality of the disease[1,2].More evidence showed that corticosteroid,an immunomodulatory agent,reduces both the need of invasive mechanical ventilation and lowers the mortality of severe cOVID-19 ***,its optimal dose and therapeutic duration is still *** REcOVERY trial revealed that using corticosteroid up to 10 days reduced the mortality of hospitalized cOVID-19 patients[3]and a finding also upheld by a meta-analysis by cano et al.[4].To the best of our knowledge,currently,there is no study evaluating disease progression after discontinuation of corticosteroid treatment in cOVID-19 patients with ARDs.

关键词： mortality acute distress

sYNTHEsIs,cHARAcTERIZATION AND PHOTOLUMINEscENT PROPERTIEs OF NEW PLATINUM-cONTAINING POLY(FLUORENYLENEETHYNYLENE) ANcHORED WITH cARBAZOLE PENDANTs

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chinese Journal of Polymer science 2009年第4期27卷 455-464页

作者： cheuk-lam Ho 黄维扬 Department of chemistry and centre for Advanced Luminescence Materials Hong Kong Baptist UniversityWaterloo RoadKowloon Tong Invited lecture presented at the 4(th) International conference on Photoresponsive Organics and Polymers

A new luminescent and thermally stable platinum(Ⅱ) polyyne polymer trans-[-Pt(PBu_3)_2c=cArc=c-]_n(P1) containing the 2,7-fluorene chromophoric spacer substituted by pendant carbazolyl group via long alkyl bridges. The regiochemical structures of these compounds were studied by various spectroscopic *** report the photophysical properties of this group 10 polymetallayne and a comparison was made to its binuclear model complex trans-[Pt(Ph)(PEt_3)_2c≡cArc≡cPt(Ph)(PEt_3)_2](M1) as well as to those wit...

关键词： Alkyne carbazole Fluorene Photoluminescence Platinum

A Deep Learning Based Approach for context-Aware Multi-criteria Recommender systems

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computer systems science & Engineering 2023年第1期44卷 471-483页

作者： son-lam VU Quang-Hung LE Faculty of Information Technology Quy Nhon UniversityQuy Nhon CityVietnam

Recommender systems are similar to an informationfiltering system that helps identify items that best satisfy the users’demands based on their pre-ference ***-aware recommender systems(cARss)and multi-criteria recommender systems(McRss)are extensions of traditional recommender *** have integrated additional contextual information such as time,place,and so on for providing better ***,the majority of cARss use ratings as a unique criterion for building ***,McRss utilize user preferences in multiple criteria to better generate *** to now,how to exploit context in McRss is still an open *** paper proposes a novel approach,which relies on deep learning for context-aware multi-criteria recommender *** apply deep neural network(DNN)mod-els to predict the context-aware multi-criteria ratings and learn the aggregation *** conduct experiments to evaluate the effect of this approach on the real-world dataset.A significant result is that our method outperforms other state-of-the-art methods for recommendation effectiveness.

关键词： Recommender systems context-aware multi-criteria deep learning deep neural network

The relationship between chimeric RNAs and gene fusions:Potential implications of reciprocity in cancer

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Journal of Genetics and Genomics 2020年第7期47卷 341-348页

作者： Justin Elfman lam-Phong Pham Hui Li Department of Biochemistry and Molecular Genetics School of MedicineUniversity of VirginiaCharlottesvilleVA22904 USA Department of Pathology School of MedicineUniversity of VirginiaCharlottesvilleVA22904 USA

Gene fusions have long been considered hallmarks of *** into characterization of their prevalence,cause,and function have provided significant progress toward improvements in diagnosis,prognosis assessment,and treatment of numerous *** recently,detection of intergenically spliced chimeric RNAs in cancer has spurred efforts to characterize these transcripts,anticipating similar successes in translation to the *** of chimeric RNAs in normal cells,especially those which precede canonical translocations such as PAX3-F0X01 and JAZF1-JJAZ1,suggests that these physiologically regulated transcripts may function as proto-oncogenic factors,in that their dysregulation can lead to cancer *** findings have given rise to conjecture regarding chimeric RNAguided rearrangements giving rise to fusion genes,termed the cart-before-the-horse ***,we provide context for the relationship between gene fusions,chimeric RNAs,and cancer;assemble evidence in support of the cart-before-the-horse hypothesis;and discuss potential advantages of targeting chimeric RNAs in cancer treatment.

关键词： cancer diagnosis horse

Investigation of the hydrodynamic behavior of diatom aggregates using particle image velocimetry

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Journal of Environmental sciences 2012年第7期24卷 1157-1164页

作者： Feng Xiao Xiaoyan Li Kitming lam Dongsheng Wang state Key Laboratory of Environmental Aquatic chemistry Research Center for Eco-Environrnental SciencesChinese Academy of SciencesBeijing 100085China Environmental Engineering Research centre Department of Civil EngineeringUniversity of Hong KongHong KongChina

The hydrodynamic behavior of diatom aggregates has a significant influence on the interactions and flocculation kinetics of algae. However, characterization of the hydrodynamics of diatoms and diatom aggregates in water is rather difficult. In this laboratory study, an advanced visualization technique in particle image velocimetry （PIV） was employed to investigate the hydrodynamic properties of settling diatom aggregates. The experiments were conducted in a settling column filled with a suspension of fluorescent polymeric beads as seed tracers. A laser light sheet was generated by the PIV setup to illuminate a thin vertical planar region in the settling column, while the motions of particles were recorded by a high speed charge-coupled device （ccD） camera. This technique was able to capture the trajectories of the tracers when a diatom aggregate settled through the tracer suspension. The PIV results indicated directly the curvilinear feature of the streamlines around diatom aggregates. The rectilinear collision model largely overestimated the collision areas of the settling particles. Algae aggregates appeared to be highly porous and fractal, which allowed streamlines to penetrate into the aggregate interior. The diatom aggregates have a fluid collection efficiency of 10%-40%. The permeable feature of aggregates can significantly enhance the collisions and flocculation between the aggregates and other small particles including algal cells in water.

关键词： diatom aggregate fluid collection efficiency fractal particle image velocimetry