bluuebunny/crossref_metadata_2025_split huggingface dataset:
Epoxy Sepabeads: A Novel Epoxy Support for Stabilization of Industrial Enzymes via Very Intense Multipoint Covalent Attachment
Authors: Mateo Cesar , Abian Olga , Fernández‐Lorente Gloria , Pedroche Justo , Fernández‐Lafuente Roberto , Guisan Jose M. 
Published: July 2002

AbstractSepabeads‐EP (a new epoxy support) has been utilized to immobilize‐stabilize the enzyme penicillin G acylase (PGA) via multipoint covalent attachment. These supports are very robust and suitable for industrial purposes. Also, the internal geometry of the support is composed by cylindrical pores surrounded by the convex surfaces (this offers a good geometrical congruence for reaction with the enzyme), and it has a very high superficial density of epoxy groups (around 100 μmol/mL). These features should permit a very intense enzyme‐support interaction. However, the final stability of the immobilized enzyme is strictly dependent on the immobilization protocol. By using conventional immobilization protocols (neutral pH values, nonblockage of the support) the stability of the immobilized enzyme was quite similar to that achieved using Eupergit C to immobilize the PGA. However, when using a more sophisticated three‐step immobilization/stabilization/blockage procedure, the Sepabeads derivative was hundreds‐fold more stable than Eupergit C derivatives. The protocol used was as follows: (i) the enzyme was first covalently immobilized under very mild experimental conditions (e.g., pH 7.0 and 20 °C); (ii) the already immobilized enzyme was further incubated under more drastic conditions (higher pH values, long incubation periods, etc.) in order to “facilitate” the formation of new covalent linkages between the immobilized enzyme molecule and the support; (iii) the remaining epoxy groups of the support were blocked with very hydrophilic compounds to stop any additional interaction between the enzyme and the support. This third point was found to be critical for obtaining very stable enzymes: derivatives blocked with mercaptoethanol were much less stable than derivatives blocked with glycine or other amino acids. This was attributed to the better masking of the hydrophobicity of the support by the amino acids (having two charges).
Anaerobic Dechlorinating Bacteria
Authors: El Fantroussi Saïd , Naveau Henry , Agathos Spiros N. 
Published: July 2002

AbstractAnaerobic dehalogenation is attracting great interest since it opens new research horizons based on the novel biochemical mechanisms identified in this field such as halorespiration, i.e. the utilization of halogenated compounds as electron acceptors. Moreover, anaerobic bacteria seem to be more efficient than their aerobic counterparts in removing halogen atoms from polyhalogenated compounds. Thus, anaerobic dehalogenation can be considered as a promising means for bioremediation treatments of persistently polluted environments. In this line, identification of pure strains capable of dehalogenation will give important information about the diversity of organisms implicated in this process and also fundamental explanations of the diverse biochemical mechanisms involved. In light of these considerations, we chose to focus this review on the physiological descriptions, dechlorination activities, phylogenetic diversity, and potential biotechnological applications of these pure anaerobic strains capable of dehalogenation.
Fluctuations and anomalous transport in tokamaks
Authors: Wootton A. J. , Carreras B. A. , Matsumoto H. , McGuire K. , Peebles W. A. , Ritz Ch. P. , Terry P. W. , Zweben S. J. 
Published: July 2002

This is a review of what is known about fluctuations and anomalous transport processes in tokamaks. It mostly considers experimental results obtained after, and not included in, the reviews of Liewer [Nucl. Fusion 25, 543 (1985)], Robinson [in Turbulence and Anomalous Transport in Magnetized Plasmas (Ecole Polytechnique, Palaiseau, France, 1986), p. 21], and Surko [in Turbulence and Anomalous Transport in Magnetized Plasmas (Ecole Polytechnique, Palaiseau, France, 1986), p. 93]. Therefore much of the pioneering work in the field is not covered. Emphasis is placed on results where comparisons between fluctuations and transport properties have been attempted, particularly from the tokamak TEXT [Nucl. Technol./Fusion 1, 479 (1981)]. A brief comparison of experimentally measured total fluxes with the predictions of neoclassical theory demonstrates that transport is often anomalous; fluctuations are thought to be the cause.
The measurements necessary to determine any such fluctuation-driven fluxes are described. The diagnostics used to measure these quantities, together with some of the statistical techniques employed to analyze the data, are outlined. In the plasma edge detailed measurements of the quantities required to directly determine the fluctuation-driven fluxes are available. The total and fluctuation-driven fluxes are compared: the result emphasizes the importance of edge turbulence. No model adequately describes all the measured properties. In the confinement region experimental observations are presently restricted to measurements of density and potential fluctuations and their correlations. Various distinct turbulence features that have been observed are described, and their characteristics compared with the predictions of various models. Correlations observed between these fluctuations and plasma transport properties are summarized. A separate section on magnetic fluctuations shows there is very little information available inside the plasma, generally prohibiting quantified comparisons between fluctuation levels and transport. Both coherent and turbulent magnetic fluctuations are addressed, and the differences between low and high plasma pressure (low and high beta) are noted. The contributions of alternate confinement devices, such as stellarators and reversed field pinches, to understanding tokamak anomalous transport are discussed. Finally, future directions are proposed.
The surveillant assemblage
Authors: Haggerty Kevin D. , Ericson Richard V. 
Published: July 2002

ABSTRACTGeorge Orwell's ‘Big Brother’ and Michel Foucault's ‘panopticon’ have dominated discussion of contemporary developments in surveillance. While such metaphors draw our attention to important attributes of surveillance, they also miss some recent dynamics in its operation. The work of Gilles Deleuze and Felix Guattari is used to analyse the convergence of once discrete surveillance systems. The resultant ‘surveillant assemblage’ operates by abstracting human bodies from their territorial settings, and separating them into a series of discrete flows. These flows are then reassembled in different locations as discrete and virtual ‘data doubles’. The surveillant assemblage transforms the purposes of surveillance and the hierarchies of surveillance, as well as the institution of privacy.
‘Truth’ and ‘Lies’ Revisited
Authors: Sikes Pat 
Published: July 2002

ABSTRACTAnecdotal evidence suggests that many qualitative researchers have had the experience of discovering that their informants had told them lies. This is quite different to those instances where faulty memory, subjective perception, partial or erroneous knowledge, a desire to give the researcher what they think they want, or even where a ‘personal myth’ comes in to play, because a lie is a conscious and deliberate intention to deceive. What should researchers do when they discover that they have been misled? What are the implications for qualitative methodology and its practitioners in the light of the criteria for good practice outlined in the Tooley Report? This article draws on two examples of informants who lied, in order to explore some of the questions and issues that can arise. It suggests, tentatively, that generic criteria may not always be sufficiently sensitive to cope with complexities of social life.
Relationships Between Symbolic Play, Functional Play, Verbal And Non‐Verbal Ability In Young Children
Authors: Lewis Vicky , Boucher Jill , Lupton Laura , Watson Samantha 
Published: July 2002

AbstractIt is well established that certain aspects of play in young children are related to their emerging linguistic skills. The present study examined the relationships between functional play, symbolic play, non‐verbal ability, and expressive and receptive language in normally developing children aged between 1 and 6 years using standardized assessment procedures, including a recently developed Test of Pretend Play (ToPP). When effects of chronological age were partialled out, symbolic play remained significantly correlated with both expressive and receptive language, but not with functional play or non‐verbal ability; and functional play was only correlated significantly with expressive language. It is concluded that ToPP will provide practitioners with a useful way of assessing symbolic ability in children between the ages of 1 and 6 years, and will contribute to the assessment and diagnosis of a number of communication difficulties, and have implications for intervention.
The Localization of Bullous Pemphigoid Antigen 180 (BP180) in Hemidesmosomes Is Mediated by Its Cytoplasmic Domain and Seems to be Regulated by the β4 Integrin Subunit
Authors: Borradori Luca , Koch Peter J. , Niessen Carien M. , Erkeland Stefan , Leusden Manuel R. van , Sonnenberg Arnoud 
Published: July 2002

Bullous pemphigoid antigen 180 (BP180) is a component of hemidesmosomes, i.e., cell-substrate adhesion complexes. To determine the function of specific sequences of BP180 to its incorporation in hemidesmosomes, we have transfected 804G cells with cDNA-constructs encoding wild-type and deletion mutant forms of human BP180. The results show that the cytoplasmic domain of BP180 contains sufficient information for the recruitment of the protein into hemidesmosomes because removal of the extracellular and transmembrane domains does not abolish targeting. Expression of chimeric proteins, which consist of the membrane targeting sequence of K-Ras fused to the cytoplasmic domain of BP180 with increasing internal deletions or lacking the NH2 terminus, indicates that the localization of BP180 in hemidesmosomes is mediated by a segment that spans 265 amino acids. This segment comprises two important regions located within the central part and at the NH2 terminus of the cytoplasmic domain of BP180.
To investigate the effect of the α6β4 integrin on the subcellular distribution of BP180, we have transfected COS-7 cells, which lack α6β4 and BP180, with cDNAs for BP180 as well as for human α6A and β4. We provide evidence that a mutant form of BP180 lacking the collagenous extracellular domain as well as a chimeric protein, which contains the entire cytoplasmic domain of BP180, are colocalized with α6β4. In contrast, when cells were transfected with cDNAs for α6A and mutant forms of β4, either lacking the cytoplasmic COOH-terminal half or carrying phenylalanine substitutions in the tyrosine activation motif of the cytoplasmic domain, the recombinant BP180 molecules were mostly not colocalized with α6β4, but remained diffusely distributed at the cell surface. Moreover, in cells transfected with cDNAs for α6A and a β4/β1 chimera, in which the cytoplasmic domain of β4 was replaced by that of the β1 integrin subunit, BP180 was not colocalized with the α6β4/β1 chimera in focal adhesions, but remained again diffusely distributed. These results indicate that sequences within the cytoplasmic domain of β4 determine the subcellular distribution of BP180.
The Symmetrical Structure of Structural Maintenance of Chromosomes (SMC) and MukB Proteins: Long, Antiparallel Coiled Coils, Folded at a Flexible Hinge
Authors: Melby Thomas E. , Ciampaglio Charles N. , Briscoe Gina , Erickson Harold P. 
Published: July 2002

Structural maintenance of chromosomes (SMC) proteins function in chromosome condensation and several other aspects of DNA processing. They are large proteins characterized by an NH2-terminal nucleotide triphosphate (NTP)-binding domain, two long segments of coiled coil separated by a hinge, and a COOH-terminal domain. Here, we have visualized by EM the SMC protein from Bacillus subtilis (BsSMC) and MukB from Escherichia coli, which we argue is a divergent SMC protein. Both BsSMC and MukB show two thin rods with globular domains at the ends emerging from the hinge. The hinge appears to be quite flexible: the arms can open up to 180°, separating the terminal domains by 100 nm, or close to near 0°, bringing the terminal globular domains together.
A surprising observation is that the ∼300–amino acid–long coiled coils are in an antiparallel arrangement. Known coiled coils are almost all parallel, and the longest antiparallel coiled coils known previously are 35–45 amino acids long. This antiparallel arrangement produces a symmetrical molecule with both an NH2- and a COOH-terminal domain at each end. The SMC molecule therefore has two complete and identical functional domains at the ends of the long arms. The bifunctional symmetry and a possible scissoring action at the hinge should provide unique biomechanical properties to the SMC proteins.
Characterization of the Kinetochore Binding Domain of CENP-E Reveals Interactions with the Kinetochore Proteins CENP-F and hBUBR1
Authors: Chan G.K.T. , Schaar B.T. , Yen T.J. 
Published: July 2002

We have identified a 350–amino acid domain in the kinetochore motor CENP-E that specifies kinetochore binding in mitosis but not during interphase. The kinetochore binding domain was used in a yeast two-hybrid screen to isolate interacting proteins that included the kinetochore proteins CENP-E, CENP-F, and hBUBR1, a BUB1-related kinase that was found to be mutated in some colorectal carcinomas (Cahill, D.P., C. Lengauer, J. Yu, G.J. Riggins, J.K. Wilson, S.D. Markowitz, K.W. Kinzler, and B. Vogelstein. 1998. Nature. 392:300–303). CENP-F, hBUBR1, and CENP-E assembled onto kinetochores in sequential order during late stages of the cell cycle. These proteins therefore define discrete steps along the kinetochore assembly pathway.
Kinetochores of unaligned chromosome exhibited stronger hBUBR1 and CENP-E staining than those of aligned chromosomes. CENP-E and hBUBR1 remain colocalized at kinetochores until mid-anaphase when hBUBR1 localized to portions of the spindle midzone that did not overlap with CENP-E. As CENP-E and hBUBR1 can coimmunoprecipitate with each other from HeLa cells, they may function as a motor–kinase complex at kinetochores. However, the complex distribution pattern of hBUBR1 suggests that it may regulate multiple functions that include the kinetochore and the spindle midzone.
Novel Protein Kinases Ark1p and Prk1p Associate with and Regulate the Cortical Actin Cytoskeleton in Budding Yeast
Authors: Cope M.Jamie T.V. , Yang Shirley , Shang Ching , Drubin David G. 
Published: July 2002

Ark1p (actin regulating kinase 1) was identified as a yeast protein that binds to Sla2p, an evolutionarily conserved cortical actin cytoskeleton protein. Ark1p and a second yeast protein, Prk1p, contain NH2-terminal kinase domains that are 70% identical. Together with six other putative kinases from a number of organisms, these proteins define a new protein kinase family that we have named the Ark family.
Lack of both Ark1p and Prk1p resulted in the formation of large cytoplasmic actin clumps and severe defects in cell growth. These defects were rescued by wild-type, but not by kinase-dead versions of the proteins. Elevated levels of either Ark1p or Prk1p caused a number of actin and cell morphological defects that were not observed when the kinase-dead versions were overexpressed instead. Ark1p and Prk1p were shown to localize to actin cortical patches, making these two kinases the first signaling proteins demonstrated to be patch components. These results suggest that Ark1p and Prk1p may be downstream effectors of signaling pathways that control actin patch organization and function. Furthermore, results of double-mutant analyses suggest that Ark1p and Prk1p function in overlapping but distinct pathways that regulate the cortical actin cytoskeleton.
The Role of Actin in Spindle Orientation Changes during the Saccharomyces cerevisiae Cell Cycle
Authors: Theesfeld Chandra L. , Irazoqui Javier E. , Bloom Kerry , Lew Daniel J. 
Published: July 2002

In the budding yeast Saccharomyces cerevisiae, the mitotic spindle must align along the mother-bud axis to accurately partition the sister chromatids into daughter cells. Previous studies showed that spindle orientation required both astral microtubules and the actin cytoskeleton. We now report that maintenance of correct spindle orientation does not depend on F-actin during G2/M phase of the cell cycle. Depolymerization of F-actin using Latrunculin-A did not perturb spindle orientation after this stage. Even an early step in spindle orientation, the migration of the spindle pole body (SPB), became actin-independent if it was delayed until late in the cell cycle.
Early in the cell cycle, both SPB migration and spindle orientation were very sensitive to perturbation of F-actin. Selective disruption of actin cables using a conditional tropomyosin double-mutant also led to de- fects in spindle orientation, even though cortical actin patches were still polarized. This suggests that actin cables are important for either guiding astral microtubules into the bud or anchoring them in the bud. In addition, F-actin was required early in the cell cycle for the development of the actin-independent spindle orientation capability later in the cell cycle. Finally, neither SPB migration nor the switch from actin-dependent to actin-independent spindle behavior required B-type cyclins.
Multiple cadherin extracellular repeats mediate homophilic binding and adhesion
Authors: Chappuis-Flament Sophie , Wong Ellen , Hicks Les D. , Kay Cyril M. , Gumbiner Barry M. 
Published: July 2002

The extracellular homophilic-binding domain of the cadherins consists of 5 cadherin repeats (EC1–EC5). Studies on cadherin specificity have implicated the NH2-terminal EC1 domain in the homophilic binding interaction, but the roles of the other extracellular cadherin (EC) domains have not been evaluated. We have undertaken a systematic analysis of the binding properties of the entire cadherin extracellular domain and the contributions of the other EC domains to homophilic binding.
Lateral (cis) dimerization of the extracellular domain is thought to be required for adhesive function. Sedimentation analysis of the soluble extracellular segment of C-cadherin revealed that it exists in a monomer–dimer equilibrium with an affinity constant of ∼64 μM. No higher order oligomers were detected, indicating that homophilic binding between cis-dimers is of significantly lower affinity.
The homophilic binding properties of a series of deletion constructs, lacking successive or individual EC domains fused at the COOH terminus to an Fc domain, were analyzed using a bead aggregation assay and a cell attachment–based adhesion assay. A protein with only the first two NH2-terminal EC domains (CEC1-2Fc) exhibited very low activity compared with the entire extracellular domain (CEC1-5Fc), demonstrating that EC1 alone is not sufficient for effective homophilic binding. CEC1-3Fc exhibited high activity, but not as much as CEC1-4Fc or CEC1-5Fc. EC3 is not required for homophilic binding, however, since CEC1-2-4Fc and CEC1-2-4-5Fc exhibited high activity in both assays. These and experiments using additional EC combinations show that many, if not all, the EC domains contribute to the formation of the cadherin homophilic bond, and specific one-to-one interaction between particular EC domains may not be required. These conclusions are consistent with a previous study on direct molecular force measurements between cadherin ectodomains demonstrating multiple adhesive interactions (Sivasankar, S., W. Brieher, N. Lavrik, B. Gumbiner, and D. Leckband. 1999. Proc. Natl. Acad. Sci. USA. 96:11820–11824; Sivasankar, S., B. Gumbiner, and D. Leckband. 2001. Biophys J. 80:1758–68). We propose new models for how the cadherin extracellular repeats may contribute to adhesive specificity and function.
Asymptotic behavior of nonexpansive sequences and mean points
Authors: Jung Jong , Park Jong 
Published: July 2002

Let

E
E

be a real Banach space with norm

‖
⋅
‖

\Vert \cdot \Vert

and let

{

x
n

}

n
≥
0

\{x_n\}_{n \ge 0}

be a nonexpansive sequence in

E
E

(i.e.,

‖

x

i
+
1

−

x

j
+
1

‖
≤
‖

x
i

−

x
j

‖

\Vert x_{i + 1} - x_{j + 1}\Vert \le \Vert x_i - x_j\Vert

for all

i
,
j
≥
0

i, j \ge 0

). Let

K
=

⋂

n
=
1

∞

c
o

¯

{
{

x
i

−

x

i
−
1

}

i
≥
n

}

K = \bigcap _{n = 1}^{\infty }\overline {co}\{\{x_i - x_{i - 1}\}_{i \ge n}\}

. We deal with the mean point of

{

x
n

n

}

\{\frac {x_n}{n}\}

concerning a Banach limit. We show that if

E
E

is reflexive and

d
=
d
(
0
,
K
)

d = d(0,K)

, then

d
=
d
(
0
,

c
o

¯

{

x
n

−

x
0

n

}
)

d = d(0,\overline {co}\{\frac {x_n - x_0}{n}\})

and there exists a unique point

z
0

z_0

with

‖

z
0

‖
=
d

\Vert z_0\Vert = d

such that

z
0

∈

c
o

¯

{

x
n

−

x
0

n

}

z_0 \in \overline {co}\{\frac {x_n - x_0}{n}\}

. This result is applied to obtain the weak and strong convergence of

{

x
n

n

}

\{\frac {x_n}{n}\}

.
A class of complete second order linear differential equations
Authors: Oka Hirokazu 
Published: July 2002

This paper is concerned with a class of complete second order linear differential equations in a Banach space. We show the existence and uniqueness of classical solutions of

(SE)

{

u
(
t
)
=
A
(
t
)

u
′

(
t
)
+
B
(
t
)
u
(
t
)
+
f
(
t
)

for

t
∈
[
0
,
T
]

u
(
0
)
=
x
and

u
′

(
0
)
=
y
.

\begin{equation}\tag {SE} \begin {cases} u(t) = A(t)u’(t) + B(t)u(t) + f(t) \text {for $t \in [0,T]$} \ u(0) = x \text {and} u’(0) = y. \end{cases} \end{equation}
On the set of topologically invariant means on an algebra of convolution operators on 𝐿^{𝑝}(𝐺)
Authors: Granirer Edmond 
Published: July 2002

Let

G
G

be a locally compact group,

A

p

=

A

p

(
G
)

A_{p}=A_{p}(G)

the Banach algebra defined by Herz; thus

A

2

(
G
)
=
A
(
G
)

A_{2}(G)=A(G)

is the Fourier algebra of

G
G

. Let

P

M

p

=

A

p

∗

PM_{p}=A^{*}_{p}

the dual,

J
⊂

A

p

J \subset A_{p}

a closed ideal, with zero set

F
=
Z
(
J
)

F=Z(J)

, and

P

=
(

A

p

/

J

)

∗

\mathbb {P} = (A_{p}/J)^{*}

. We consider the set

T
I

M

P

(
x
)
⊂

P

∗

TIM_{\mathbb {P}}(x) \subset {\mathbb {P}}^{*}

of topologically invariant means on

P

\mathbb {P}

at

x
∈
F

x\in F

, where

F
F

is “thin.” We show that in certain cases card

T
I

M

P

(
x
)
≥

2

c

TIM_{\mathbb {P}}(x) \geq 2^{c}

and

T
I

M

P

(
x
)

TIM_{\mathbb {P}}(x)

does not have the WRNP, i.e. is far from being weakly compact in

P

∗

\mathbb {P}^{*}

. This implies the non-Arens regularity of the algebra

A

p

/

J

A_{p}/J

.
Cauchy-Schwarz and means inequalities for elementary operators into norm ideals
Authors: Jocić Danko 
Published: July 2002

The Cauchy-Schwarz norm inequality for normal elementary operators
\[

⦀

∑

n
=
1

∞

A
n

X

B
n

⦀

≤

⦀
(

∑

n
=
1

∞

A
n
∗

A
n

)

1

/

2

X
(

∑

n
=
1

∞

B
n
∗

B
n

)

1

/

2

⦀

,

\left \Vvert \sum _{n=1}^\infty A_nXB_n \right \Vvert \leq \left \Vvert (\sum _{n=1}^\infty A_n^*A_n)^{1/2}X (\sum _{n=1}^\infty B_n^*B_n)^{1/2} \right \Vvert ,

\]
implies a means inequality for generalized normal derivations
\[

⦀

A
X
+
X
B

2

⦀

≤
⦀
X

⦀

1
−

1
r

⦀

|

A

|

r

X
+
X

|

B

|

r

2

⦀

1
r

,

\left \Vvert \frac {AX+XB}2 \right \Vvert \leq \Vvert X \Vvert ^{1-\frac 1r} \left \Vvert \frac {|A|^rX+X|B|^r}2 \right \Vvert ^\frac 1r,

\]
for all

r
≥
2

r\ge 2

, as well as an inequality for normal contractions

A
A

and

B
B

\[

⦀
(
I
−

A
∗

A

)

1
2

X
(
I
−

B
∗

B

)

1
2

⦀

≤
⦀
X
−
A
X
B
⦀
,

\left \Vvert (I-A^*A) ^\frac 12X(I-B^*B)^\frac 12\right \Vvert \leq \Vvert X-AXB\Vvert ,

\]
for all

X
X

in

B
(
H
)

B(H)

and for all unitarily invariant norms

⦀
⋅
⦀
.

\Vvert \cdot \Vvert .