1,560 research outputs found
Pancreatic cancer cachexia: a review of mechanisms and therapeutics.
Over the last decade, we have gained new insight into the pathophysiology of cachexia associated with pancreatic cancer. Unfortunately, its treatment is complex and remains a challenge. Pancreatic cancer cachexia is a multifactorial syndrome characterized by uncompensated adipose tissue and skeletal muscle loss in the setting of anorexia that leads to progressive functional impairment. This paper will review the current concepts of pancreatic cancer cachexia, its assessment and pathophysiology as well as current and future treatments. The successful management of pancreatic cancer cachexia will likely require a multimodal approach that includes nutritional support and combination pharmaceutical interventions
Soft computing applications in dynamic model identification of polymer extrusion process
This paper proposes the application of soft computing to deal with the constraints in conventional modelling techniques of the dynamic extrusion process. The proposed technique increases the efficiency in utilising the available information during the model identification. The resultant model can be classified as a ‘grey-box model’ or has been termed as a ‘semi-physical model’ in the context. The extrusion process contains a number of parameters that are sensitive to the operating environment. Fuzzy ruled-based system is introduced into the analytical model of the extrusion by means of sub-models to approximate those operational-sensitive parameters. In drawing the optimal structure for the sub-models, a hybrid algorithm of genetic algorithm with fuzzy system (GA-Fuzzy) has been implemented. The sub-models obtained show advantages such as linguistic interpretability, simpler rule-base and less membership functions. The developed model is adaptive with its learning ability through the steepest decent error back-propagation algorithm. This ability might help to minimise the deviation of the model prediction when the operational-sensitive parameters adapt to the changing operating environment in the real situation. The model is first evaluated through simulations on the consistency of model prediction to the theoretical analysis. Then, the effectiveness of adaptive sub-models in approximating the operational-sensitive parameters during the operation is further investigated
Division of labor, skill complementarity, and heterophily in socioeconomic networks
Constituents of complex systems interact with each other and self-organize to
form complex networks. Empirical results show that the link formation process
of many real networks follows either the global principle of popularity or the
local principle of similarity or a tradeoff between the two. In particular, it
has been shown that in social networks individuals exhibit significant
homophily when choosing their collaborators. We demonstrate, however, that in
populations in which there is a division of labor, skill complementarity is an
important factor in the formation of socioeconomic networks and an individual's
choice of collaborators is strongly affected by heterophily. We analyze 124
evolving virtual worlds of a popular "massively multiplayer online role-playing
game" (MMORPG) in which people belong to three different professions and are
allowed to work and interact with each other in a somewhat realistic manner. We
find evidence of heterophily in the formation of collaboration networks, where
people prefer to forge social ties with people who have professions different
from their own. We then construct an economic model to quantify the heterophily
by assuming that individuals in socioeconomic systems choose collaborators that
are of maximum utility. The results of model calibration confirm the presence
of heterophily. Both empirical analysis and model calibration show that the
heterophilous feature is persistent along the evolution of virtual worlds. We
also find that the degree of complementarity in virtual societies is positively
correlated with their economic output. Our work sheds new light on the
scientific research utility of virtual worlds for studying human behaviors in
complex socioeconomic systems.Comment: 14 Latex pages + 3 figure
Assessment of heavy metal pollution in the Straits of Johore by using transplanted caged mussel, Perna viridis
In this study, a polluted site at Kg. Pasir Puteh was assessed for heavy metal pollution by using transplanted caged mussel (Perna viridis) from a relatively clean population, Sg. Melayu; both are located in the Strait of Johore. For control purposes, the P. viridis from Kg. Pasir Puteh were also simultaneously transplanted in Sg. Melayu at the same time. It was found that Zn was the metal which got accumulated fastest in the transplanted mussel while Cd was the slowest. This study indicated that the byssus of Perna viridis was most effective for biomonitoring of Cd, Ni, Pb and Zn, while the shell could be used for the biomonitoring of Cu, Ni and Pb and the total soft tissue for the biomonitoring of Ni since they were able to accumulate and eliminate the respective metals well. By using mussel as a biomonitor, the present study found that Kg. Pasir Puteh, which is located in the eastern part of the Strait of Johore, had significantly higher contamination and bioavailabilities of Cd, Cu, Fe, Ni, Pb and Zn. Therefore, the use of the transplanted caged mussels is very useful for heavy metal assessment purposes since it can increase the validity of data interpretation by minimizing ecological factors
Erratum to: Comparative Studies of the Growth and Characterization of Germanium Epitaxial Film on Silicon (001) with 0° and 6° Offcut
In the original article we presented results that show that the strain in germanium (Ge) epitaxial films grown directly on a silicon (Si) (001) with 6° offcut has a tensile strain of 0.6%. This strain value is much higher than the typical tensile strain value of 0.2% reported for Ge/Si. This discrepancy is due unintentional omission of the Si offcut angle and azimuth angle (φ) of the sample during high-resolution x-ray diffraction (HRXRD) measurement, and it has unfortunately resulted in a misleading result
Depuration of trace metals in transplanted perna viridis from polluted site at Kg Pasir Puteh to relatively unpolluted sites at Kg Sg Melayu and Sg Belungkor in the straits of Johore
In this study, the green-lipped mussels Perna viridis were transplanted from a relatively unpolluted site at Kg. Sg Melayu (KSM) to a known polluted site at Kg Pasir Puteh (KPP) and an unpolluted site at Sg. Belungkor (SB). Total soft tissues of mussels were determined for Ag, As, Be, Co, Cr, Cs, Hg, Li, Mn, Se, Sr and V by using an Inductively Coupled Plasma-mass Spectrometer. After transplantation periods (2 and 6 weeks) to KPP, concentrations of As, Co, Cr, Hg, Li, Be, V, Cs, Mn and Sr increased but the concentrations of Ag and Se decreased after transplantation of 2 and 6 weeks. This indicated that KPP is almost confirmed as having the highest bioavailabilities of the above 10 metals than KSM and SB. However, the higher levels of Ag and Se found in the transplanted mussels at KSM should be investigated in future studies. After transplantation periods (2 and 6 weeks) to SB, concentrations of Co, Cr, Hg, Be, V, Cs, Se, Mn and Sr decreased but the concentrations of Ag and Li increased after transplantation of 2 and 6 weeks. This verified that SB is suitable coastal water for depuration of Co, Cr, Hg, Be, V, Cs, Se, Mn and Sr. However, higher levels of Ag and Li at SB than KSM could be attributed to unknown pollution source in the surrounding area which should merit further studies
Assessment of heavy metal pollution in the Straits of Johore by using transplanted caged mussels, Perna viridis
In this study, a polluted site at Kg. Pasir Puteh was assessed for heavy metal pollution by using transplanted caged mussel (Perna viridis) from a relatively clean population, Sg. Melayu; both are located in the Strait of Johore. For control purposes, the P. viridis from Kg. Pasir Puteh were also simultaneously transplanted in Sg. Melayu at the same time. It was found that Zn was the metal which got accumulated fastest in the transplanted mussel while Cd was the slowest. This study indicated that the byssus of Perna viridis was most effective for biomonitoring of Cd, Ni, Pb and Zn, while the shell could be used for the biomonitoring of Cu, Ni and Pb and the total soft tissue for the biomonitoring of Ni since they
were able to accumulate and eliminate the respective metals well. By using mussel as a biomonitor, the present study found that Kg. Pasir Puteh, which is located in the eastern part of the Strait of Johore, had significantly higher contamination and bioavailabilities of Cd, Cu, Fe, Ni, Pb and Zn. Therefore, the use of the transplanted caged mussels is very useful for heavy metal assessment purposes since it can increase the validity of data interpretation by minimizing ecological factors
High energy amplitude as an admixture of "soft" and "hard" Pomerons
In this paper an attempt is made to find an interface of the perturbative
BFKL Pomeron with the non-perturbative Pomeron originating from
non-perturbative QCD phenomena such as QCD instantons and/or scale anomaly. The
main idea is that the non-perturbative Pomeron involves a large scale (), which is larger than the scale from which perturbative QCD is
applicable. One key result is that even for processes involving a large hard
scale (such as DIS) the low behavior is determined by an effective Pomeron
with an intercept having an essential non-perturbative QCD contribution.Comment: 29 pages, 13 fugures. Accepted for publication in Nucl. Phys.
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