1,498 research outputs found
The mitogenic potential of heparin-binding epidermal growth factor in the human endometrium is mediated by the epidermal growth factor receptor and is modulated by tumor necrosis factor-alpha
No full textHeparin-binding epidermal growth factor (HB-EGF), a member of the epidermal growth factor (EGF) family, is implicated in a variety of biological processes, including reproduction. Previous studies describe increased levels of HB-EGF in the human endometrium during the midsecretory stage of the menstrual cycle, suggesting a function for HB-EGF in implantation of the human blastocyst. Here we have investigated the expression and function of the soluble and transmembrane forms of HB-EGF in the human endometrium. We show that the expression of the transmembrane form of HB-EGF in the human endometrium is modulated according to the stage of the menstrual cycle. We present data demonstrating that both the soluble and transmembrane forms of HB-EGF induce DNA synthesis in human endometrial stromal cells. Furthermore, TNFalpha has a cooperative effect on HB-EGF, EGF, TGFalpha, and betacellulin-induced DNA synthesis in stromal cells, suggesting roles for the EGF family and TNFalpha in regeneration and maturation of human endometrium. Induction of DNA synthesis by HB-EGF and its modulation by TNFalpha in endometrial stromal cells are mediated by the EGF receptor and not the HB-EGF receptor ErbB4. Our data suggest key functions for HB-EGF, TNFalpha, and the EGF receptor in endometrial maturation, via autocrine/paracrine and juxtacrine pathways, in preparation for embryo implantation
On the Security of Non-Linear HB (NLHB) Protocol Against Passive Attack
No full textAs a variant of the HB authentication protocol for RFID systems, which relies on the complexity of decoding linear codes against passive attacks, Madhavan et al. presented Non-Linear HB(NLHB) protocol. In contrast to HB, NLHB relies on the complexity of decoding a class of non-linear codes to render the passive attacks proposed against HB ineffective. Based on the fact that there has been no passive solution for the problem of decoding a random non-linear code, the authors have claimed that NLHB’s security margin is very close to its key size. In this paper, we show that passive attacks against HB protocol can still be applicable to NLHB and this protocol does not provide the desired security margin. In our attack, we first linearize the non-linear part of NLHB to obtain a HB equivalent for NLHB, and then exploit the passive attack techniques proposed for the HB to evaluate the security margin of NLHB. The results show that although NLHB’s security margin is relatively higher than HB against similar passive attack techniques, it has been overestimated and, in contrary to what is claimed, NLHB is vulnerable to passive attacks against HB, especially when the noise vector in the protocol has a low weight
Knowledge
No full textKnowledge Nowadays, in what is often referred to as ‘knowledge based’ economies, corporations are giving serious attention to managing and exploiting knowledge, perceiving it to be the most important strategic resource. Commentators and researchers claim that if corporations are going to sustain competitive advantage in the knowledge economy then they must continually innovate, and this requires the development of a more strategic approach to ‘knowledge management’ (Hansen, 1999). However, the notion that knowledge can (or should) be managed, in much the same way that other corporate resources (e.g. finance, labour) are managed, has been subject to significant critique in recent years (Alvesson et al, 2002; Fuller, 2002; Newell et al, 2002; Swan and Scarbrough, 2001). In this chapter, we will build on these earlier critiques by outlining the treatment of ‘knowledge’ in corporate life and by reviewing what actually happens when organizations attempt to ‘manage’ knowledge and what assumptions underpi
Legal regulation of prices in Tanzania : an examination of the Regulation of Prices Act 1973 as a tool of social change and development
No full textDrawing mainly from the Tazanian experience this study
attempts to review the principal issues in the legal regulation of
prices, by identifying both the general and specific importance
of law in this respect. The position I shall present is that
legal control is both necessary and desirable for the welfare
and social development of the people. The key issue is whether
the market-place will perform its function satisfactory: Will
it produce socially desirable results? If it will not, why will
it not? And will legal regulation help to do the job a little
better?
In an attempt to answer some of these questions,
first of all, outline the basic issues raised by the study in
the first Chapter. Then I examine the general case for price
controls - the theory about the controls, the motives and reasons
for their imposition and the manner in which they are effected
in different economic systems. This is done in Chapter Two. Relying
most on the available literature on the regulatory process, this
Chapter also looks at the relationship between law and economic
regulation and concludes that the effectiveness of law depends
on the existence of a conducive socio-economic environment. In
Chapter Three I describe the past record of price control laws
in Tanzania. I conclude that despite the failure in the past,
the controls still constitute an important policy instrument
in the transition to socialism. In Chapters Four and Five I describe
the manner in which the current regulations are implemented and
the problems encountered. I conclude that the operational performance
of the controls is constrained by internal and external influences on the economic and political life of the country. In the concluding
Chapter I assess the impact of the controls: Do the controls
work? Do people buy goods at the controlled prices? Why today
the controls are almost popularly accepted as worthwhile? I conclude
that while there may be no measurable economic gains derived
by consumers, the controls have a stabilising effect on the social
and political front. In the final section I argue that the
future success of the legislation depends on creating a correspondence
between the economic structures and the control system. What
makes the controls ineffective is not so much defects in the
law but the contradictions between the orientation of and functioning
of the economic system and the ideological commitment
On
No full textIn this paper, this author proved that always has
the integral solutions for Then we conjecture the equation always has the integral solutions
Database of surface level atmospheric dimethylsulfide (DMS) collected for the project "The Great Barrier Reef as a significant source of climatically relevant aerosol particles"
No full text<p>The data provided here consists of surface level atmospheric DMS measurements collected at Heron Island on the southern Great Barrier Reef (23.44°S, 151.91°E) in January-February 2018. This data has resulted from a series of campaigns conducted on the Great Barrier Reef (GBR) to examine the significance of the GBR as a source of new aerosol particles. Accompanying the atmospheric DMS data set are one minute averaged particle number concentrations for the size range fractions 0.5 - 2.5 micron and >2.5 micron collected using a Dylos DC1700 air quality monitor. Surface level solar irradiance (300 -1100 nm) is also provided with the data collected in Jan-Feb 2018 at Heron Island.</p><p>Hilton B Swan collected the atmospheric DMS data using a gas chromatograph fitted with a sulfur-specific pulsed flame photometric detector (GC-PFPD). An auto-sampler was used with the GC-PFPD to provide continuous sampling with a 20 min cycle time. For a complete description of the methodology used refer to HB Swan et al., (2015) Analytical Methods, doi 10.1039/c5ay00269a</p>
The Analysis of Wafe Refraction using SWAN Model
No full textWave simulation is important problem in nearshore coastal design process. Determination of proper wave parameter will provide reliable and accurate design, therefore modeling usually needed to simulate this process where numerical model is the right choice because of its cost is cheaper and the result is quite accurate. SWAN (Simulating Wave Nearshore) is numerical model that already used widely to simulate wave in coastal area. In this research we analyze wave refraction by SWAN model with any coastal profile (m) i.e. 0,01 , 0,03 and 0,05. This simulation also applied in the real problem at Tegal port in Central Java Province. According to the result of this model we find that in the same direction, height, and period, the height of wave break will increase as the coastal slope increase. These problems arise due to decreasing in value of db/Hb that means the peak wave is become steep. Coastal Profile affect the wave height (duo to refraction) about 2%-34%. The jetty at Tegal Port induce the wave height big alteration at dock pond (228,91%) at wave direction 30o, while at groove, back and head of the jetty, wave reduction reach until 12,96% ; 0,02% and 3,55% at incoming wave direction 45o. In the head of the jetty, the wave almost doesn’t being reduced because diffraction and wave reflection doesn’t have significant effect
Coral Reef Emissions of Atmospheric Dimethylsulfide and the Influence on Marine Aerosols in the Southern Great Barrier Reef, Australia
No full textVariability in atmospheric dimethylsulfide (DMSa) and the potential influence on atmospheric aerosols was investigated at Heron Island in the southern Great Barrier Reef (GBR), Australia. This work compiles previously published DMSa data (reported in Swan, Jones, Deschaseaux, & Eyre, 2017, https://doi.org/10.5194/bg‐14‐229‐2017), with additional surveys of DMSa, atmospheric particle number concentration, and other oceanic and atmospheric data sets. DMSa was higher in summer (mean 3.2 nmol m−3/78 ppt) than winter (mean 1.3 nmol m−3/32 ppt), reflective of seasonal shifts in phytoplankton biomass and emissions from corals in the southern GBR. Seasonally extreme spikes in DMSa were detected during low tide and low wind speed, supporting findings that the coral reef can be an important source of DMSa above background oceanic emissions. A significant link was present between DMSa and aerosol concentration (ranging from 0.5 to 2.5 μm) during calm, daylight hours, when conditions were optimal for the local oxidation of DMSa to sulfate aerosol precursors. This link may reflect condensational growth of existing fine particles (< 0.5 μm), which is the dominant pathway by which biogenic trace gases influence aerosols in the marine boundary layer. Aerosol concentration significantly correlated with reduced surface solar irradiance and sea surface temperature, which is potential evidence of a local negative feedback mitigating coral physiological stress. These findings provide a step toward a better understanding of the processes influencing DMSa and aerosol concentrations and of the consequences for the local radiative balance over coral reefs; an increasingly important topic with ongoing ocean warming and coral bleaching.Full Tex
SOME NEWMAN-TYPE THEOREMS FOR MAPS FROM RIEMANNIAN-MANIFOLDS INTO MANIFOLDS
No full textMathematics, AppliedMathematicsSCI(E)1ARTICLE53-5911
SOME BORSUK-ULAM-TYPE THEOREMS FOR MAPS FROM RIEMANNIAN-MANIFOLDS INTO MANIFOLDS
No full textMathematics, AppliedMathematicsSCI(E)1ARTICLE61-6711
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