bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factors influencing the efficiency of isolation and culture of human embryonic germ cells
Authors: Jin-Lian Hua , Zhong-Ying Dou , Xiao-Ming Xu , Song Li , Yu-Ai Yang , An-Min Lei 
Published: January 2005

AbstractEmbryonic germ (EG) cells are pluripotent cells derived from the primordial germ cells of gonads, gonadal ridges and mesenteries, and analogies of foetuses, with the ability to undergo both self-renewal and multiple differentiation. These cells can differentiate into derivatives of all three embryonic germ layers when transferred to anin vitroenvironment and have the ability to form any fully differentiated cell of the body. The present paper investigates some factors influencing the efficiency of isolation and culture of human EG cells, such as foetus age, culture serum, added cytokines and feeder cells. The results demonstrate that foetuses of 7–12 weeks are optimal forin vitroculture of human EG cells. The basic medium consisted of DMEM, 1×non-essential amino acids, 2 mM l-glutamine and 1 mM sodium pyruvate. Supplementation with 15% foetal bovine serum, 4 ng/ml human recombinant leukaemia inhibitory factor, 4 ng/ml basic fibroblast growth factor and 20 ng/ml stem cell factor clearly improved the efficiency of isolation and culture of human EG cells. Murine embryonic fibroblasts were better feeder cells than human embryonic fibroblasts, bovine embryonic fibroblasts or STO cell line.
An infinite family of bounds on zeros of analytic functions and relationship to Smale’s bound
Authors: Kalantari Bahman 
Published: January 2005

Smale’s analysis of Newton’s iteration function induce a lower bound on the gap between two distinct zeros of a given complex-valued analytic function

f
(
z
)

f(z)

. In this paper we make use of a fundamental family of iteration functions

B
m

(
z
)

B_m(z)

,

m
≥
2

m \geq 2

, to derive an infinite family of lower bounds on the above gap. However, even for

m
=
2

m=2

, where

B
2

(
z
)

B_2(z)

coincides with Newton’s, our lower bound is more than twice as good as Smale’s bound or its improved version given by Blum, Cucker, Shub, and Smale. When

f
(
z
)

f(z)

is a complex polynomial of degree

n
n

, for small

m
m

the corresponding bound is computable in

O
(
n
log
⁡
n
)

O(n \log n)

arithmetic operations. For quadratic polynomials, as

m
m

increases the lower bounds converge to the actual gap. We show how to use these bounds to compute lower bounds on the distance between an arbitrary point and the nearest root of

f
(
z
)

f(z)

. In particular, using the latter result, we show that, given a complex polynomial

f
(
z
)
=

a
n

z
n

+
⋯
+

a
0

f(z)=a_n z^n + \cdots + a_0

,

a
n

a
0

≠
0

a_na_0 \not =0

, for each

m
≥
2

m \geq 2

we can compute upper and lower bounds

U
m

U_m

and

L
m

L_m

such that the roots of

f
(
z
)

f(z)

lie in the annulus

{
z
:

L
m

≤

|

z

|

≤

U
m

}

\{z : L_m \leq |z| \leq U_m\}

. In particular,

L
2

=

1
2

/

max
{

|

a
k

/

a
0

|

1

/

k

:
k
=
1
,
…
,
n
}

L_2={1 \over 2}/\max \{ |{{a_k} / {a_0}}|^{1/k}: k=1, \dots , n\}

,

U
2

=
2
max
{

|

a

n
−
k

/

a
n

|

1

/

k

:
k
=
1
,
…
,
n
}

U_2=2 \max \{ |{{a_{n-k}} / {a_n}}|^{1/k}: k=1, \dots , n\}

; and

L
3

=
[
(

5

−
1
)

/

2
]

/

max
{
(

|

a
1

a

k
−
1

−

a
0

a

k

|

/

|

a
0
2

|

)

1

/

k

:
k
=
2
,
…
,
n
+
1
}

L_3 =[(\sqrt {5}-1)/2] / \max \{ ({{|a_1a_{k-1}-a_0a_{k}|} / {|a_0^2|}})^{1/k}: k=2, \dots , n+1 \}

,

U
3

=
[
(

5

+
1
)

/

2
]
max
{
(

|

a

n
−
1

a

n
−
k
+
1

−

a
n

a

n
−
k

|

/

|

a
n
2

|

)

1

/

k

:
k
=
2
,
…
,
n
+
1
}

U_3 = [(\sqrt {5}+1)/2] \max \{ ({{|a_{n-1}a_{n-k+1}-a_na_{n-k}|} / {|a_n^2|}} )^{1/k}: k=2, \dots , n+1 \}

, where

a

−
1

=

a

n
+
1

=
0

a_{-1}=a_{n+1}=0

. An application of the latter bounds is within Weyl’s classical quad-tree algorithm for computing all roots of a given complex polynomial.
Finding 𝐶₃-strong pseudoprimes
Authors: Zhang Zhenxiang 
Published: January 2005

Let

q
1

>

q
2

>

q
3

q_1>q_2>q_3

be odd primes and

N
=

q
1

q
2

q
3

N=q_1q_2q_3

. Put
\[

d
=
gcd
(

q
1

−
1
,

q
2

−
1
,

q
3

−
1
)
and

h
i

=

q
i

−
1

d

,

i
=
1
,
2
,
3.

d=\gcd (q_1-1,q_2-1,q_3-1) \text { and } h_i=\tfrac {q_i-1}d, \;i=1,2,3.

\]
Then we call

d
d

the kernel, the triple

(

h
1

,

h
2

,

h
3

)

(h_1,h_2,h_3)

the signature, and

H
=

h
1

h
2

h
3

H=h_1h_2h_3

the height of

N
N

, respectively. We call

N
N

a

C
3

C_3

-number if it is a Carmichael number with each prime factor

q
i

≡
3

mod

4

q_i\equiv 3\mod 4

. If

N
N

is a

C
3

C_3

-number and a strong pseudoprime to the

t
t

bases

b
i

b_i

for

1
≤
i
≤
t

1\leq i\leq t

, we call

N
N

a

C
3

C_3

-spsp

(

b
1

,

b
2

,
…
,

b
t

)

(b_1, b_2,\dots ,b_t)

. Since

C
3

C_3

-numbers have probability of error

1

/

4

1/4

(the upper bound of that for the Rabin-Miller test), they often serve as the exact values or upper bounds of

ψ
m

\psi _m

(the smallest strong pseudoprime to all the first

m
m

prime bases). If we know the exact value of

ψ
m

\psi _m

, we will have, for integers

n
>

ψ
m

n>\psi _m

, a deterministic efficient primality testing algorithm which is easy to implement. In this paper, we first describe an algorithm for finding

C
3

C_3

-spsp(2)’s, to a given limit, with heights bounded. There are in total

21978
21978

C
3

C_3

-spsp

(
2
)

(2)

’s

>

10

24

>10^{24}

with heights

>

10
9

>10^9

. We then give an overview of the 21978

C
3

C_3

- spsp(2)’s and tabulate

54
54

of them, which are

C
3

C_3

-spsp’s to the first

8
8

prime bases up to

19
19

; three numbers are spsp’s to the first 11 prime bases up to 31. No

C
3

C_3

-spsp’s

>

10

24

>10^{24}

to the first

12
12

prime bases with heights

>

10
9

>10^9

were found. We conjecture that there exist no

C
3

C_3

-spsp’s

>

10

24

>10^{24}

to the first

12
12

prime bases with heights

≥

10
9

\geq 10^9

and so that

ψ

12

a
m
p
;
=
3186

65857

83403

11511

67461

(24 digits)

a
m
p
;
=
399165290221
⋅
798330580441
,

\begin{equation*} \begin {split} \psi _{12}&= 3186\; 65857\; 83403\; 11511\; 67461\; \text {(24 digits)} \\ &=399165290221\cdot 798330580441, \end{split}\end{equation*}

which was found by the author in an earlier paper. We give reasons to support the conjecture. The main idea of our method for finding those

21978
21978

C
3

C_3

-spsp

(
2
)

(2)

’s is that we loop on candidates of signatures and kernels with heights bounded, subject those candidates

N
=

q
1

q
2

q
3

N=q_1q_2q_3

of

C
3

C_3

-spsp

(
2
)

(2)

’s and their prime factors

q
1

,

q
2

,

q
3

q_1,q_2,q_3

to Miller’s tests, and obtain the desired numbers. At last we speed our algorithm for finding larger

C
3

C_3

-spsp’s, say up to

10

50

10^{50}

, with a given signature to more prime bases. Comparisons of effectiveness with Arnault’s and our previous methods for finding

C
3

C_3

-strong pseudoprimes to the first several prime bases are given.
Knowledge‐based design aid tool for power electronic converters
Authors: Omrane Bouketir , Mariun Norman , Aris Ishak , Mahmoud Senan , Soib Taib 
Published: January 2005

PurposeThe paper aims to develop a CAD tool power electronics converters.Design/methodology/approachIntegration of knowledge base techniques with OOP paradigm. Using Visual Basis class builder, 15 classes were built to form the kernel of the tool's KB.FindingsA knowledge‐based CAD tool was developed to ease the design of power electronics converters. It can be considered a learning aid tool too.Research limitations/implicationsThe knowledge base of developed tool can be expanded to accommodate large number of topologies. The GUI can be also ameliorated to a better look and interaction process.Practical implicationsWith proper enhancements, the purpose of the developed tool can be upgraded from educational one to industrial one.Originality/valueBeside the methodology, the new thing in the paper is the specificity of the application of the tool (i.e. in power electronics).
Transformation of geometric models into orthogonal polyhedra using fuzzy logic
Authors: Obiała R. , Topping B.H.V. , Seed G.M. , Clark D.E.R. 
Published: January 2005

PurposeThis paper describes how non‐orthogonal geometric models may be transformed into orthogonal polyhedral models. The main purpose of the transformation is to obtain a geometric model that is easy to describe and further modify without loss of topological information from the original model.Design/methodology/approachThe transformation method presented in this paper is based on fuzzy logic (FL). The idea of using FL for this type of transformation was first described by Takahashi and Shimizu. This paper describes both philosophy and techniques behind the transformation method as well as its application to some example 2D and 3D models. The problem in this paper is to define a transformation technique that will change a non‐orthogonal model into a similar orthogonal model. The orthogonal model is unknown at the start of the transformation and will only be specified once the transformation is complete. The model has to satisfy certain conditions, i.e. it should be orthogonal.FindingsThe group of non‐orthogonal models that contain triangular faces such as tetrahedra or pyramids cannot be successfully recognized using this method. This algorithm fails to transform these types of problem because to do so requires modification of the structure of the model. It appears that only when the edges are divided into pieces and the sharp angles are smoothed then the method can be successfully applied. Even though the method cannot be applied to all geometric models many successful examples for 2D and 3D transformation are presented. Orthogonal models with the same topology, which make them easier to describe, are obtained.Originality/valueThis transformation makes it possible to apply simple algorithms to orthogonal models enabling the solution of complex problems usually requiring non‐orthogonal models and more complex algorithms.
Reliability analysis of concrete structures with neural networks and response surfaces
Authors: Martins Gomes Herbert , Miguel Awruch Armando 
Published: January 2005

PurposeTo research the feasibility in using artificial neural networks (ANN) and response surfaces (RS) techniques for reliability analysis of concrete structures.Design/methodology/approachThe evaluation of the failure probability and safety levels of structural systems is of extreme importance in structural design, mainly when the variables are eminently random. It is necessary to quantify and compare the importance of each one of these variables in the structural safety. RS and the ANN techniques have emerged attempting to solve complex and more elaborated problems. In this work, these two techniques are presented, and comparisons are carried out using the well‐known first‐order reliability method (FORM), with non‐linear limit state functions. The reliability analysis of reinforced concrete structure problems is specially considered taking into account the spatial variability of the material properties using random fields and the inherent non‐linearity.FindingsIt was observed that direct Monte Carlo simulation technique has a low performance in complex problems. FORM, RS and neural networks techniques are suitable alternatives, despite the loss of accuracy due to approximations characterizing these methods.Research limitations/implicationsThe examples tested are limited to moderated large non‐linear reinforced concrete finite element models. Conclusions are drawn based on the examples.Practical implicationsSome remarks are outlined regarding the fact that RS and ANN techniques have presented equivalent precision levels. It is observed that in problems where the computational cost of structural evaluations (computing failure probability and safety levels) is high, these two techniques could improve the performance of the structural reliability analysis through simulation techniques.Originality/valueThis paper is important in the field of reliability analysis of concrete structures specially when neural networks or RS techniques are used.
Awareness of message source and its association with the impacts of sun protection campaigns in Australia
Authors: Smith Ben J. , Bauman Adrian E. , McKenzie Jeanie , Thomas Margaret 
Published: January 2005

PurposeTo examine whether awareness of the source of sun protection campaigns in New South Wales, Australia was associated with message recall and sun protection knowledge and behaviours.Design/methodology/approachTelephone surveys of random samples (n=800) of parents and other carers of children under 12 years of age were conducted before and after the first two campaigns and after the third campaign.FindingsRecognition of the NSW Cancer Council (NSWCC) as the message source increased after each campaign. Cross‐sectional analyses revealed that after the first and third campaigns those who could identify the NSWCC were 1.4‐1.7 times more likely than those who could not to demonstrate knowledge about child sun protection practices (p<0.05). After the first campaign those with accurate message source awareness were 1.4 times more likely to report using sunscreen or clothing to protect their children, while after campaign three this awareness was associated with a greater likelihood (OR 1.6, p<0.05) of using hats, sunscreen and protective clothing.Research limitations/implicationsWhile causality cannot be determined using a cross‐sectional design, the use of serial population surveys to analyse the relationship between message source awareness and sun protection knowledge and behaviours strengthens the basis for examining the role of this factor.Practical implicationsPresenting a readily identifiable and credible message source is likely to enhance the impact of health campaigns and this factor should be given attention in the pre‐testing of communications.Originality/valueThe importance of a credible communication source has been postulated by various theorists, but this one of few studies to examine the role played this factor in a population‐wide, health promotion campaign.
The role of university libraries in supporting research in Hong Kong: facing a new challenge
Authors: Wai Fan Ka 
Published: January 2005

PurposeTo discuss how Hong Kong university libraries can help young professors and PhD students publish their articles in SCI (Science Citation Index) and SSCI (Social Science Citation Index) journals.Design/methodology/approachWith reference to the opinions of experts on how to publish work successfully, this paper provides practical advice for university libraries in Hong Kong.FindingsAfter collecting the opinions of experts and browsing the web sites of many university libraries throughout the world, suggests that Hong Kong universities can offer a variety of services in supporting research. The university libraries may build up electronic resources to gather more research information and journals information for helping young professors and PhD students publish their works.Practical implicationsTo provide very useful and practical advice for Hong Kong university libraries when facing the new challenge in support of research.Originality/valueDuring recent years, the Hong Kong universities have been facing budget cuts from the government, and have been placed under the pressure of transforming into centers of excellence and establishing themselves among the best in the world. This paper offers practical help to Hong Kong university libraries such as how to play an active and important role in providing a greater support service for young professors and PhD students that will help in the development of their academic careers.
An exploratory study of groupware use in the knowledge management process
Authors: Bhatt Ganesh , Gupta Jatinder N.D. , Kitchens Fred 
Published: January 2005

PurposeAims to explore the relationships between groupware use and the knowledge management process.Design/methodology/approachThe activities comprising the knowledge management process are conceptualized as: knowledge creation, knowledge maintenance, knowledge distribution, and knowledge review and revision. The data for this exploratory study were gathered through a telephone survey of managers at Fortune 1000 firm divisions. Based on the prior literature, it was expected that use of certain types of groupware and certain aspects of the knowledge management process would be significantly associated with each other.FindingsThe results of this exploratory study show that the groupware tools which enhance or support traditional aural media were significantly associated with most of the knowledge management processes we identified. However, e‐mail is the sole groupware tool that is significantly associated with knowledge distribution.Originality/valueAs an exploratory study, this research highlights some interesting trends in the knowledge management process, and suggests multiple lines of future research.
Multi‐factor productivity measurement model for service organisation
Authors: Sahay B.S. 
Published: January 2005

PurposeTo discuss the concept of productivity in the service sector and to present a multifactor productivity measurement model for a service organisation.Design/methodology/approachEmploys a case study approach, featuring a service organisation which provides a range of engineering services to different industries. The model focuses on objectives of the organization and overall results rather than the individual departmental activities.FindingsThe case study shows how different factors of static, dynamic and development parameters can be taken into account to calculate the total productivity of an organisation.Research limitations/implicationsThe case study organization represents only one industry sector. However, it is claimed that the generic model for productivity measurement described may be used by any type of service organisation. Warns that it is not always possible to assess the nature and extent of bias introduced by the measures selected and the weightages assigned to these measures.Practical implicationsThe model can determine the gap between what is actually accomplished and what it is possible to accomplish (unlike subjective targeting), providing the potential for improvement.Originality/valueThe model presented is important in that it attempts to measure unmeasurable factors.
Business analytics: getting behind the numbers
Authors: Emblemsvåg Jan 
Published: January 2005

PurposeTo identify, discuss and provide a solution for a common problem in the mathematical analyses in business analyses, namely, paralysis by analysis.Design/methodology/approachThe paper first discusses the scale and frequency of the paralysis by analysis problem, before discussing it in more depth before addressing a fundamental problem, which is an important root of the paralysis by analysis problem, the indiscriminate usage of central tendency measures. Finally, it discusses how variance can be turned from being a liability into an asset. The approach is conversational but examples and a case study are provided to substantiate the arguments.FindingsThe paper provides some recommendations for avoiding paralysis by analysis.Practical implicationsBasically, the paper shows by argument and example why practitioners and some researchers need to better understand the limitations and promises of mathematical analyses and to some extent how to incorporate this understanding into their work.Originality/valueThere is nothing really new in this paper, but it discusses a problem that for some reason is often ignored by practitioners and some researchers. The true value of the paper therefore lies in making practitioners, in particular, more aware of the limitations as well as the possibilities in the mathematical analyses performed in business analytics so that they can better understand what they are doing and hence get behind the numbers, as it were.
Predation of Colorado potato beetle eggs by a polyphagous ladybeetle in the presence of alternate prey: potential impact on resistance evolution
Authors: Mallampalli Nikhil , Gould Fred , Barbosa Pedro 
Published: January 2005

AbstractThe influence of prey choice on the predation of a target prey item by a polyphagous insect predator was investigated in field plot studies. The target prey consisted of eggs of the Colorado potato beetle (CPB), Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae), and the predator was the 12‐spotted ladybeetle, Coleomegilla maculata Lengi (Coleoptera: Coccinellidae). Eggs of the European corn borer (ECB), Ostrinia nubilalis Hübner (Lepidoptera: Pyralidae), and nymphs and adults of the green peach aphid, Myzus persicae Sulzer (Homoptera: Aphididae), comprised the alternative prey choices. The objectives of these studies were to: (1) examine predation in a multiprey scenario likely to occur in an agroecosystem, and (2) use the data to simulate the impact of predator‐induced mortality on the evolution of resistance to Bt‐transgenic plants in the target herbivore. Simulations of the rate of resistance evolution were carried out using a deterministic genetic model. Experiments were performed using potato field plots planted in a manner reflecting a 25% or 50% non‐transgenic refuge. CPB eggs were infested so as to mimic the densities of resistant and susceptible populations that might occur in commercial Bt‐transgenic plantings. Densities of predators and alternate prey species were chosen to represent those that might typically occur in potato crops in the eastern USA. Simulation results indicated that when ECB eggs were present, predation on CPB eggs either became inversely spatially density‐dependent, or increased significantly in a density‐dependent manner. When aphids were present, predation became positively density‐dependent. Model simulations predicted that ECB egg presence is beneficial, in that resistance was delayed by up to 40 pest generations (as compared to the scenario with CPB as the only prey), while aphid presence accelerated resistance evolution by 18 generations. Results suggest that resistance management strategies should take into account the composition of prey species available to generalist predators typically present, so as to best delay pest adaptation to Bt‐toxins.