bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the differential osmotic adjustments between roots and leaves of maize seedlings with single or combined NPK-nutrient supply
Authors: Studer Christoph , Hu Yuncai , Schmidhalter Urs
Published: March 2007

Many physiological mechanisms associated with nutrient supply have been implicated as improving plant growth under drought conditions. However, benefits to plant growth under drought might derive from an increased recovery of soil water through osmotic adjustment in the shoots and especially in the roots. Thus, experiments were carried out to investigate the effects of the nutrients N, P and K applied singly or in combination, on the osmotic adjustment and turgor maintenance in the roots and leaves of maize seedlings. The seedlings were harvested between 18 and 37 days after sowing according to the soil matric threshold potentials. Soil matric potentials and shoot and root biomass were determined at harvest. Turgor pressure and osmotic adjustment of the leaves and roots were estimated by measurements of their water and osmotic potentials. Results showed that plants with either of the combined fertilisation treatments NPK or NP grew faster at a given level of drought stress than those with no fertilisation, N, P or K applied individually or the combined nutrient treatments PK and NK. Among the fertiliser applications with either a single or two combined nutrients, plants treated with any of N, P or NP grew faster than those with either K or NK. The association between the interactive effects of nutrients and drought stress on the osmotic adjustment and turgor maintenance in roots may partially explain the role of nutrients in drought tolerance of maize seedlings. In particular, the roots exhibited a higher osmotic adjustment than the leaves for all nutrient treatments, suggesting that shoot growth shows a higher sensitivity to water deficit compared to root growth. We conclude that the maintained turgor of roots under drought stress obtained with an optimal nutrient supply results in better root growth and apparently promotes overall plant growth, suggesting that osmotic adjustment is an adaptation not only for surviving stress, but also for growth under such conditions.
Research note: Energy partitioning in photosystem II complexes subjected to photoinhibitory treatment
Authors: Kornyeyev Dmytro , Hendrickson Luke
Published: March 2007

Chlorophyll a fluorescence measured in vivo is frequently used to study the role of different processes influencing the distribution of excitation energy in PSII complexes. Such studies are important for understanding the regulation of photosynthetic electron transport. However, at the present time, there is no unified methodology to analyse the energy partitioning in PSII. In this article, we critically assess several approaches recently developed in this area of research and propose new simple equations, which can be used for de-convolution of non-photochemical energy quenching in PSII complexes.
Structures of bird communities in woodland remnants in central New South Wales, Australia
Authors: Briggs S. V. , Seddon J. A. , Doyle S. J.
Published: March 2007

The overall aim of this study was to investigate structures of bird communities in remnants of fragmented box/cypress pine woodlands in central New South Wales, Australia, to guide habitat rehabilitation. The aims of the study were to: (1) determine how bird densities and species richness varied with remnant category; (2) determine how ranked densities of bird species varied by feeding group with remnant category; and (3) provide information on structures of bird communities in box/cypress pine woodlands to guide restoration. Structures of bird communities varied with remnant category. Large remnants had the most species whereas medium-sized and small remnants in low condition had the fewest. Bird densities increased with decreasing remnant area although densities did not differ significantly between remnant categories. Ranked bird densities varied between remnant categories, with relatively even distributions in large remnants in high condition, and uneven distributions in small remnants in low condition. Densities of small insectivores were much lower in small, low-condition remnants than in large, high-condition remnants. Densities of generalists such as noisy miner and galah showed the reverse pattern. The structures of bird communities in large remnants in good condition provide a reference state for assessing recovery of bird communities.
Combinatorial transcriptional control of the lactose operon of
Escherichia coli
Authors: Kuhlman Thomas , Zhang Zhongge , Saier Milton H. , Hwa Terence
Published: March 2007

The goal of systems biology is to understand the behavior of the whole in terms of knowledge of the parts. This is hard to achieve in many cases due to the difficulty of characterizing the many constituents involved in a biological system and their complex web of interactions. The
lac
promoter of
Escherichia coli
offers the possibility of confronting “system-level” properties of transcriptional regulation with the known biochemistry of the molecular constituents and their mutual interactions. Such confrontations can reveal previously unknown constituents and interactions, as well as offer insight into how the components work together as a whole. Here we study the combinatorial control of the
lac
promoter by the regulators Lac repressor (LacR) and cAMP-receptor protein (CRP). A previous
in vivo
study [Setty Y, Mayo AE, Surette MG, Alon U (2003)
Proc Natl Acad Sci USA
100:7702–7707] found gross disagreement between the observed promoter activities and the expected behavior based on the known molecular mechanisms. We repeated the study by identifying and removing several extraneous factors that significantly modulated the expression of the
lac
promoter. Through quantitative, systematic characterization of promoter activity for a number of key mutants and guided by the thermodynamic model of transcriptional regulation, we were able to account for the combinatorial control of the
lac
promoter quantitatively, in terms of a cooperative interaction between CRP and LacR-mediated DNA looping. Specifically, our analysis indicates that the sensitivity of the inducer response results from LacR-mediated DNA looping, which is significantly enhanced by CRP.
Hepatitis C virus production by human hepatocytes dependent on assembly and secretion of very low-density lipoproteins
Authors: Huang Hua , Sun Fang , Owen David M. , Li Weiping , Chen Yan , Gale Michael , Ye Jin
Published: March 2007

Hepatitis C virus (HCV) and triglyceride-rich very low-density lipoproteins (VLDLs) both are secreted uniquely by hepatocytes and circulate in blood in a complex. Here, we isolated from human hepatoma cells the membrane vesicles in which HCV replicates. These vesicles, which contain the HCV replication complex, are highly enriched in proteins required for VLDL assembly, including apolipoprotein B (apoB), apoE, and microsomal triglyceride transfer protein. In hepatoma cells that constitutively produce infectious HCV, HCV production is reduced by two agents that block VLDL assembly: an inhibitor of microsomal triglyceride transfer protein and siRNA directed against apoB. These results provide a possible explanation for the restriction of HCV production to the liver and suggest new cellular targets for treatment of HCV infection.
MitoNEET is an iron-containing outer mitochondrial membrane protein that regulates oxidative capacity
Authors: Wiley Sandra E. , Murphy Anne N. , Ross Stuart A. , van der Geer Peter , Dixon Jack E.
Published: March 2007

Members of the thiazolidinedione (TZD) class of insulin-sensitizing drugs are extensively used in the treatment of type 2 diabetes. Pioglitazone, a member of the TZD family, has been shown to bind specifically to a protein named mitoNEET [Colca JR, McDonald WG, Waldon DJ, Leone JW, Lull JM, Bannow CA, Lund ET, Mathews WR (2004)
Am J Physiol
286:E252–E260]. Bioinformatic analysis reveals that mitoNEET is a member of a small family of proteins containing a domain annotated as a CDGSH-type zinc finger. Although annotated as a zinc finger protein, mitoNEET contains no zinc, but instead contains 1.6 mol of Fe per mole of protein. The conserved sequence C-X-C-X
2
-(S/T)-X
3
-P-X-C-D-G-(S/A/T)-H is a defining feature of this unique family of proteins and is likely involved in iron binding. Localization studies demonstrate that mitoNEET is an integral protein present in the outer mitochondrial membrane. An amino-terminal anchor sequence tethers the protein to the outer membrane with the CDGSH domain oriented toward the cytoplasm. Cardiac mitochondria isolated from mitoNEET-null mice demonstrate a reduced oxidative capacity, suggesting that mito- NEET is an important iron-containing protein involved in the control of maximal mitochondrial respiratory rates.
Centralizers in free Poisson algebras
Authors: Makar-Limanov Leonid , Umirbaev Ualbai
Published: March 2007

We prove an analog of the Bergman Centralizer Theorem for free Poisson algebras over an arbitrary field of characteristic

0
0

. Some open problems are formulated.
A new explicit expression of the Contou-Carrère symbol
Authors: Romo Fernando
Published: March 2007

The aim of this note is to offer a new explicit expression of the Contou-Carrère symbol that depends only on a product of a finite number of terms. As an application, we obtain an explicit formula for a Witt Residue.
A new proof and generalizations of Gearhart’s theorem
Authors: Phong Vu
Published: March 2007

Let

H
H

be a Hilbert space, let

A
P
(

R

,
H
)

AP(\textbf {R},H)

be the space of almost periodic functions from

R

\textbf {R}

to

H
H

, and let

A
A

be a closed densely defined linear operator on

H
H

. For a closed subset

Λ
⊂

R

\Lambda \subset \textbf {R}

, let

M
(
Λ
)

M(\Lambda )

be the subspace of

A
P
(

R

,
H
)

AP(\textbf {R},H)

consisting of functions with spectrum contained in

Λ
\Lambda

. We prove that the following properties are equivalent: (i) for every function

f
∈
M
(
Λ
)

f\in M(\Lambda )

there exists a unique mild solution

u
∈
M
(
Λ
)

u\in M(\Lambda )

of equation

u
′

(
t
)
=
A
u
(
t
)
+
f
(
t
)

u’(t)=Au(t)+f(t)

; (ii)

i
Λ
⊂
ρ
(
A
)

i\Lambda \subset \rho (A)

and

sup

λ
∈
Λ

‖
(
i
λ
−
A

)

−
1

‖
>
∞

\sup _{\lambda \in \Lambda }\|(i\lambda -A)^{-1}\|>\infty

. The case

Λ
=
{
2
π
k
:
k
=
0
,
±
1
,
±
2
,
.
.
.
}

\Lambda =\{2\pi k: k=0,\pm 1,\pm 2,...\}

yields a new proof of the well-known Gearhart’s spectral mapping theorem.
On the Helton class of 𝑝-hyponormal operators
Authors: Kim Yoenha , Ko Eungil , Lee Ji
Published: March 2007

In this paper we show that the Helton class of

p
p

-hyponormal operators has scalar extensions. As a corollary we get that each operator in the Helton class of

p
p

-hyponormal operators has a nontrivial invariant subspace if its spectrum has its interior in the plane.
A generalization of the prolate spheroidal wave functions
Authors: Zayed Ahmed
Published: March 2007

Many systems of orthogonal polynomials and functions are bases of a variety of function spaces, such as the Hermite and Laguerre functions which are orthogonal bases of

L
2

(
−
∞
,
∞
)

L^2(-\infty , \infty )

and

L
2

(
0
,
∞
)
,

L^2(0,\infty ),

and the Jacobi polynomials which are an orthogonal basis of a weighted

L
2

(
−
1
,
1
)
.

L^2(-1,1).

The associated Legendre functions, and more generally, the spheroidal wave functions are also an orthogonal basis of

L
2

(
−
1
,
1
)
.

L^2(-1,1).

The prolate spheroidal wave functions, which are a special case of the spheroidal wave functions, possess a very surprising and unique property. They are an orthogonal basis of both

L
2

(
−
1
,
1
)

L^2(-1,1)

and a subspace of

L
2

(
−
∞
,
∞
)
,

L^2(-\infty , \infty ),

known as the Paley-Wiener space of bandlimited functions. They also satisfy a discrete orthogonality relation. No other system of classical orthogonal functions is known to possess this strange property. This raises the question of whether there are other systems possessing this property. The aim of the article is to answer this question in the affirmative by providing an algorithm to generate such systems and then demonstrating the algorithm by a new example.
Drifted Laplace operators on homogeneous trees
Authors: Casadio Tarabusi Enrico , Figà-Talamanca Alessandro
Published: March 2007

We determine the spectrum and the resolvent operator of a drifted Laplace operator on a homogeneous tree, obtaining qualitatively different results according to the sign of the drift in the direction of a boundary point.
The geography of symplectic 4-manifolds with an arbitrary fundamental group
Authors: Park Jongil
Published: March 2007

In this article, for each finitely presented group

G
G

, we construct a family of minimal symplectic

4
4

-manifolds with

π
1

=
G

\pi _1 =G

which cover most lattice points

(
x
,

c

)

(x, {\mathbf c})

with

x
x

large in the region

0
≤

c

>
9
x

0 \leq {\mathbf c} > 9x

. Furthermore, we show that all these

4
4

-manifolds admit infinitely many distinct smooth structures.
Alternating forms and the Brauer group of a geometric field
Authors: Brussel Eric
Published: March 2007

We compute the theory of

H

2

(
G
,

Q

/

Z

)

H^{2}(G,\mathbb {Q}/\mathbb {Z})

for any proabelian group

G
G

, using a natural isomorphism with the group

Alt
⁡
(
G
,

Q

/

Z

)

\operatorname {Alt}(G,\mathbb {Q}/\mathbb {Z})

of continuous alternating forms. We use this to establish a sort of generic behavioral ideal, or role model, for the Brauer group

Br
(
F
)

\text {Br}(F)

of a geometric field

F
F

of characteristic zero. We show this ideal is attained in several interesting cases.
Nash type inequalities for fractional powers of non-negative self-adjoint operators
Authors: Bendikov Alexander , Maheux Patrick
Published: March 2007

Assuming that a Nash type inequality is satisfied by a non-negative self-adjoint operator

A
A

, we prove a Nash type inequality for the fractional powers

A

α

A^{\alpha }

of

A
A

. Under some assumptions, we give ultracontractivity bounds for the semigroup

(

T

t
,

α

)

(T_{t,{\alpha }})

generated by

−

A

α

-A^{\alpha }

.
The expansion factors of an outer automorphism and its inverse
Authors: Handel Michael , Mosher Lee
Published: March 2007

A fully irreducible outer automorphism

ϕ
\phi

of the free group

F
n

F_n

of rank 

n
n

has an expansion factor which often differs from the expansion factor of

ϕ

−
1

\phi ^{-1}

. Nevertheless, we prove that the ratio between the logarithms of the expansion factors of

ϕ
\phi

and

ϕ

−
1

\phi ^{-1}

is bounded above by a constant depending only on the rank

n
n

. We also prove a more general theorem applying to an arbitrary outer automorphism of

F
n

F_n

and its inverse and their two spectrums of expansion factors.
The 𝐺-stable pieces of the wonderful compactification
Authors: He Xuhua
Published: March 2007

Let

G
G

be a connected, simple algebraic group over an algebraically closed field. There is a partition of the wonderful compactification

G
¯

\bar {G}

of

G
G

into finite many

G
G

-stable pieces, which was introduced by Lusztig. In this paper, we will investigate the closure of any

G
G

-stable piece in

G
¯

\bar {G}

. We will show that the closure is a disjoint union of some

G
G

-stable pieces, which was first conjectured by Lusztig. We will also prove the existence of cellular decomposition if the closure contains finitely many

G
G

-orbits.
Extension d’une valuation
Authors: Vaquié Michel
Published: March 2007

We want to determine all the extensions of a valuation

ν
\nu

of a field

K
K

to a cyclic extension

L
L

of

K
K

, i.e.

L
=
K
(
x
)

L=K(x)

is the field of rational functions of

x
x

or

L
=
K
(
θ
)

L=K(\theta )

is the finite separable extension generated by a root

θ
\theta

of an irreducible polynomial

G
(
x
)

G(x)

. In two articles from 1936, Saunders MacLane has introduced the notions of key polynomial and of augmented valuation for a given valuation

μ
\mu

of

K
[
x
]

K[x]

, and has shown how we can recover any extension to

L
L

of a discrete rank one valuation

ν
\nu

of

K
K

by a countable sequence of augmented valuations

(

μ
i

)

i
∈
I

\bigl (\mu _i\bigr ) _{i \in I}

, with

I
⊂

N

I \subset \mathbb N

. The valuation

μ
i

\mu _i

is defined by induction from the valuation

μ

i
−
1

\mu _{i-1}

, from a key polynomial

ϕ
i

\phi _i

and from the value

γ
i

=
μ
(

ϕ
i

)

\gamma _i = \mu ( \phi _i )

. In this article we study some properties of the augmented valuations and we generalize the results of MacLane to the case of any valuation

ν
\nu

of

K
K

. For this we need to introduce simple admissible families of augmented valuations

A

=

(

μ

α

)

α
∈
A

{\mathcal A} = \bigl ( \mu _{\alpha } \bigr ) _{\alpha \in A}

, where

A
A

is not necessarily a countable set, and to define a limit key polynomial and limit augmented valuation for such families. Then, any extension

μ
\mu

to

L
L

of a valuation

ν
\nu

on

K
K

is again a limit of a family of augmented valuations. We also get a “factorization” theorem which gives a description of the values

(

μ

α

(
f
)
)

( \mu _{\alpha } (f))

for any polynomial

f
f

in

K
[
x
]

K[x]

.
Legendrian contact homology in 𝑃×ℝ
Authors: Ekholm Tobias , Etnyre John , Sullivan Michael
Published: March 2007

A rigorous foundation for the contact homology of Legendrian submanifolds in a contact manifold of the form

P
×

R

P\times \mathbb {R}

, where

P
P

is an exact symplectic manifold, is established. The class of such contact manifolds includes 1-jet spaces of smooth manifolds. As an application, contact homology is used to provide (smooth) isotopy invariants of submanifolds of

R

n

\mathbb {R}^n

and, more generally, invariants of self transverse immersions into

R

n

\mathbb {R}^n

up to restricted regular homotopies. When

n
=
3

n=3

, this application is the first step in extending and providing a contact geometric underpinning for the new knot invariants of Ng.
Unitary Shimura correspondences for split real groups
Authors: Adams J. , Barbasch D. , Paul A. , Trapa P. , Vogan D.
Published: March 2007

We find a relationship between certain complementary series representations for nonlinear coverings of split simple groups, and spherical complementary series for (different) linear groups. The main technique is Barbasch’s method of calculating some intertwining operators purely in terms of the Weyl group.
Global well-posedness of the Benjamin–Ono equation in low-regularity spaces
Authors: Ionescu Alexandru , Kenig Carlos
Published: March 2007

We prove that the Benjamin–Ono initial-value problem is globally well-posed in the Banach spacesHrσ(R)H^\sigma _r(\mathbb {R}),σ≥0\sigma \geq 0, of real-valued Sobolev functions.
Puzzle geometry and rigidity: The Fibonacci cycle is hyperbolic
Authors: Smania Daniel
Published: March 2007

We describe a new and robust method to prove rigidity results in complex dynamics. The new ingredient is the geometry of the critical puzzle pieces: under control of geometry and “complex bounds”, two generalized polynomial-like maps which admit a topological conjugacy, quasiconformal outside the filled-in Julia set, are indeed quasiconformally conjugate. The proof uses a new abstract removability-type result for quasiconformal maps, following ideas of Heinonen and Koskela and of Kallunki and Koskela, optimized for applications in complex dynamics. We prove, as the first application of this new method, that, for even criticalities distinct from two, the period two cycle of the Fibonacci renormalization operator is hyperbolic with

1
1

-dimensional unstable manifold.
On the singularity probability of random Bernoulli matrices
Authors: Tao Terence , Vu Van
Published: March 2007

Let

n
n

be a large integer and let

M
n

M_n

be a random

n
×
n

n \times n

matrix whose entries are i.i.d. Bernoulli random variables (each entry is

±
1

\pm 1

with probability

1

/

2

1/2

). We show that the probability that

M
n

M_n

is singular is at most

(
3

/

4
+
o
(
1
)

)
n

(3/4 +o(1))^n

, improving an earlier estimate of Kahn, Komlós and Szemerédi, as well as earlier work by the authors. The key new ingredient is the applications of Freiman-type inverse theorems and other tools from additive combinatorics.
Nausea and vomiting in day‐case dental anaesthesia
Authors: O'DONOVAN N. , SHAW J.
Published: March 2007

The anti‐emetic effects of low‐dose droperidol (1.25 mg), ultra‐low‐dose droperidol(0.25 mg) and a placebo were compared in patients admitted for day‐case dental anaesthesia. Ultra‐low‐dose droperidol produced a significant decrease in the subjective feeling of nausea without delaying recovery or discharge from the hospital (p < 0.05). Low‐dose droperidol did not significantly reduce nausea (p > 0.05) and prolonged the recovery time (p < 0.05).
The effect of labetalol on the cardiovascular, hyperglycaemic and adrenocortical responses to surgery
Authors: CHILD C. S.
Published: March 2007

The effects of a single intravenous bolus of labetalol (0.5 mg/kg) on the cardiovascular, hyperglycaemic and adrenocortical responses to major colonic surgery were studied in five patients. Results were compared with five patients who received the same anaesthetic and had similar operations performed but who did not receive labetalol. It was observed that labetalol reduced the rises in heart rate and rate‐pressure product that occur at the time of skin incision but that it did not reduce the rise in mean arterial pressure. The rises in blood glucose and plasma cortisol were significantly less in the labetalol group after 30 minutes of surgery (p < 0.05).
Atracurium for intubation in man
Authors: STIRT J. A. , KATZ R. L. , SCHEHL D. L. , LEE C.
Published: March 2007

Atracurium is a new competitive neuromuscular blocking agent. We prospectively studied intubating conditions 2.5 minutes afer atracurium doses of 0.4 or 0.5 mg/kg. For comparison, we evaluated conditions 1 minute after suxamethonium 1.0 mg/kg, there being 10 patients in each group. The same anaesthetist evaluated conditions during laryngoscopy and intubation in all patients. Intubating conditions were excellent in 33% of patients receiving atracurium 0.4 mg/kg and 60% of those receiving atracurium 0.5 mg/kg after 2.5 minutes; conditions were excellent in 80% of patients 1 minute after suxamethonium. The incidence of successful intubation on the jrst attempt was 67%, 90%, and 100%. respectively, in the three groups. Atracurium may be a suitable alternative to suxamethonium when speed of intubation is not critical.
Gilbert's syndrome as a cause of postoperative jaundice
Authors: TAYLOR S.
Published: March 2007

A case of postoperative jaundice due to Gilbert's syndrome in a previously healthy 19‐year‐old female is presented. Signs and symptoms of jaundice developed on the second postoperative day and resolved spontaneously after 5 days. The diagnosis and characteristics of Gilbert's syndrome and other related abnormalities and factors relevant to anaesthesia which affect bilirubin metabolism are discussed.
Pleural surgery in patients with cystic fibrosis A review of anasthetic management
Authors: ROBINSON D. A. , BRANTHWAITE M. A.
Published: March 2007

Eighteen patients with advanced cystic fibrosis complicated by pneumothorax required either pleurectomy or abrasion pleurodesis. Anasthesia with nitrous oxide and oxygen was combined with controlled ventilation to both lungs, usually through a double lumen endobronchial tube. Spontaneous ventilation was restored at the end of operation in all but a minority of cases. Ten of 25 procedures were uncomplicated and a further five were followed by non‐respiratory events. Respiratory complications developed after the remaining ten procedures which were carried out on six patients, of whom only one survived for more than 6 months. All five fatal cases suffered a recurrence of pneumothorax within 6 months whereas three patients requiring re‐operation 2–6 years later survived. The principles of management are discussed and it is concluded that the operative and anasthetic hazards of thoracic surgery in this group of high‐risk cases can be avoided successfully, except when re‐operation is required within 6 months.
Hepatic metabolic ability during anasthesia Evaluation of antipyrine half‐lives and their relation to enflurane metabolism
Authors: OIKKONEN M. , ROSENBERG P. H. , NEUVONEN P. J.
Published: March 2007

The antipyrine (phenazone) half‐life was determined in 20 surgical patients to discover whether there are changes in hepatic metabolic rate during or immediately after anasthesia compared with the pre‐anasthetic rate. Nine patients received enflurane (mean duration 8.6, SD 2.0 hours) and six patients had a balanced anasthetic without enflurane (duration 4.4, SD 3.3 hours). A further five patients received a spinal anasthetic with bupivacaine. The changes in antipyrine half‐life were inconsistent, and there was no evidence of competitive metabolic inhibition, by general anasthesia. Antipyrine half‐lives did not correlate with serum fluoride levels or urinary fluoride excretion in the case of enflurane. The mean serum inorganic fluoride concentrution rose to 29 μmol/litre, and two patients had potentially nephrotoxic concentrations (64 and 50 μmol/litre) after 8 hours of exposure to enflurane though without any evident harmful effects.
Airway obstruction in infectious mononucleosis A case report
Authors: CATLING S. J. , ASBURY A. J. , LATIF M.
Published: March 2007

A case of anginose glandular fever (infectious mononucleosis) is presented in which the lymphoid tissues of Waldeyer's ring were so enlarged that they precluded intubation. The management of the case by tracheostomy is described.
Diffuse interstitial pneumonitis due to aspiration of gastric contents
Authors: CORIAT P. , LABROUSSE J. , VILDE F. , TENAILLON A. , LISSAC J.
Published: March 2007

Two cases of interstitial pneumonitis are described which developed after the acute phase of aspiration pneumonitis. Open lung biopsy revealed an interstitial. granulomatous foreign body response induced by foodstuff aspiration. Steroid treatment was administered and both cases then showed a favourable course, with the pulmonary lesion healing within 12 days.
Oxytocic drugs and anasthesia
Authors: BEEBY D. , HUGHES J. O. MORGAN
Published: March 2007

A randomised controlled clinical trial compared ergometrine 0.25 mg, syntocinon 10 mg and normal saline injected intravenously during evacuation of the uterus after spontaneous abortion showed no difference between any drug with respect to uterine contraction, change in blood pressure, blood loss or postoperative vomiting.
Idiopathic alveolar hypoventilation in Leber's disease Unusual sensitivity to mild analgesics and diazepam
Authors: HUNTER A. R.
Published: March 2007

This case history of abnormal sensitivity to ordinary doses of drug with minimal respiratory depressant activities in Leber's disease underlines the fact that patients with this abnormality are exceedingly sensitive to ordinary doses of anasthetic and sedative drugs.
Prevention of air embolism during sitting neurosurgery
Authors: SALE J. P.
Published: March 2007

An inflatable neck tourniquet has been developed for compression of the jugular veins during neurosurgery in the sitting position. Neck compression abolishes the subatmospheric pressure within the neck veins and therefore minimises the risk of air embolism. Compression can be applied throughout the initial part of the operation, a major period of risk during these surgical procedures, and released once full surgical exposure has been achieved. Venous congestion is then released and normal operating conditions are restored.
Posture and isobaric subarachnoid anasthesia
Authors: RUSSELL I. F.
Published: March 2007

Twenty‐five patients had subarachnoid anasthesia induced with 3.0 ml 0.5% bupivacaine plain. A study of the spread of analgesia demonstrated a small (2–3 segments) but signijcant (p < 0.001) rise in analgesic levels when the patients were turned from a lateral to the supine position, and from the supine to prone positions.
Reducing the haemodynamic responses to laryngoscopy and intubation
Authors: BLACK T. E. , KAY B. , HEALY T. E. J.
Published: March 2007

The effects of alfentanil and fentanyl on controlling the haemodynamic responses to laryngoscopy and intubation have been compared. Five groups often patients were studied. Induction was with thiopentone 4 mg/kg. Thirty seconds later group 1 received 1 ml/120 kg saline, group 2 received 15μg/kg alfentanil, group 3 received 30 μg/kg alfentanil and group 4 received 5 μg/kg fentanyl. Group 5 received 5 μg/kg fentanyl one minute before induction. Suxamethonium was given 60 seconak after induction and intubation of the trachea was performed 150 seconds after the start of induction. Heart rate and mean arterial pressure were recorded every minute throughout and compared with pre‐induction control values.

Control patients (group 1) showed signijicant increases associated with tracheal intubation in all haemodynamic variables. No increases were noted in groups receiving 30 μg/kg alfentanil or 5 μg/kg fentanyl. The heart rate, but not blood pressure, increased with intubation after 15 μg/kg alfentanil. The mean time to movement in 50% of the control patients was 7 minutes. In those given 15 and 30 μg/kg alfentanil it was 11 and 12 minutes respectively. In those given 5 μg/kg fentanyl it was greater than 15 minutes. Alfentanil is shown to reduce the cardiovascular responses to laryngoscopy and intubation and the effect appears to have a shorter duration than that of fentanyl.
Percutaneous lung biopsy
Authors: ROCKE D. A.
Published: March 2007

A case is reported in which percutaneous lung biopsy was followed by haemorrhage into the tracheobronchial tree. Hypoxia followed, precipitating a cardiac arrest. The haemorrhage was isolated by the insertion of a double‐lumen tube. Complications arising from this method of biopsy are reviewed and the measures necessary to control the potentially fatal problems are discussed.
A near disaster from piped gases
Authors: Carley R. H. , Houghton I. T. , Park G. R.
Published: March 2007

A defect in a piped medical gas supply resulted in a patient developing cyanosis. The following investigation revealed several faults which are discussed.
Low flow active antipollution systems
Authors: RAILTON R. , FISHER J.
Published: March 2007

The performance of two low‐flow antipollution systems has been assessed by making measurements of the nitrous oxide pollution levels with four automatic ventilators. The effectiveness of the antipollution system is dependent on the volume of gas discharged, the peak expiratory flow, the airway pressure and to a lesser extent the ventilator settings. Both systems coped adequately with the clinical conditions where inflation pressures were below 4 k Pa for two ventilators. Only one system coped with these conditions for the third ventilator. The fourth ventilator, which discharged driving gas to the respired volume, was not adequately scavenged.
Pain‐free venepuncture
Authors: Hallén B. , Olsson G. L. , Uppfeldt A.
Published: March 2007

This study was designed to assess the effect of time on the analgesic effect of a local anaesthetic cream consisting of a mixture of 5% lignocaine and prilocaine. The cream and placebo were compared in a double‐blind, randomized study in 114 children aged 4–17 years, with application times of 20 minutes and longer. A regression analysis revealed no difference in analgesic effect between cream and placebo when application times were less than 60 minutes. A cusum test showed that the effect of the cream became evident at about 60 minutes. Local adverse reactions consisted mainly of transient paleness of the skin, which did not constitute any clinical problem.
Mixed venous oxygen saturation changes during tension pneumothorax and its treatment
Authors: WOODCOCK T. E. , MURRAY S. , LEDINGHAM I. McA.
Published: March 2007

A case is reported of tension pneumothorax following left subclavian venous cannulation for placement of a fibreoptic pulmonary artery flotation catheter. Mixed venous oxygen saturation was continuously monitored and a fall in this was the first indication of the problem. Observations on the cardiovascular consequences of tension pneumothorax were made and followed during its treatment. The value of continuous monitoring of mixed venous oxygen saturation in the early detection of haemodynamic disturbances is emphasised.
A study of the efficiency of four blood microfilters
Authors: MOLLAH A. H. M. Z. , BRADSHAW E. G.
Published: March 2007

A new blood microfilter, Swank 6000–4, was compared with three established blood microfilters. Pall SQ40S, Fenwal 4C2423 and Intercept HR 18137–00 (1321). The flow rate decreased with increasing volume of filtered blood with all the microfilters (p < 0.01). When the flow rates through each type of microfilter were compared there was no significant difference between them. Screen filtration pressure was restored to normal by the Swank, Fenwal and Intercept microfilters, but remained higher after filtration through the Pall microfilter (p < 0.01). There was no evidence of red cell loss or damage with any of the microfilters after filtration.
The effects of three differing anaesthetics on the immune response
Authors: Edwards A. E. , Gemmell L. W. , Mankin P. P. , Smith C. J. , Allen J. C. , Hunter A.
Published: March 2007

A clinical study was undertaken to investigate changes in the immune response in patients undergoing three differing anaesthetic techniques for inguinal hernia repair. No significant differences between anaesthetic groups were demonstrated in the haematological parameters. The value of mitogen stimulation tests was questioned in the clinical setting. The migratory component of neutrophil function was shown to be preserved following conduction anaesthesia compared to the other anaesthetic groups and its possible advantage noted.
Hypothermic cardiopulmonary bypass in a patient with sickle‐cell trait
Authors: FOX M. A. , ABBOTT T. R.
Published: March 2007

A male patient, aged 7.5 years, with known sickle cell trait, presented for correction of Fallot's tetralogy. The successful management under hypothermic cardiopulmonary bypass is described and the behaviour of sickle haemoglobin under hypothermic conditions is discussed.
Fentanyl supplementation to inhalation anaesthesia
Authors: Ridley S.
Published: March 2007

In eight out of 15 healthy patients undergoing body surface surgery, the effect of a fentanyl infusion on a conventional thiopentone, nitrous oxide, oxygen and halothane anaesthetic was studied. The fentanyl infusion (2 μg/kg/hour) reduced the induction dose of thiopentone and caused marked respiratory depression with a reduction in the patients' response to surgery. The mean arterial pressures and pulse rates were not significantly different in each group throughout the course of the operation. The fentanyl made no difference to the patients' postoperative analgesic requirements or 10 their recovery in the first 24 hours.
Adopted foster youths’ psychosocial functioning: a longitudinal perspective
Authors: Simmel Cassandra , Barth Richard P. , Brooks Devon
Published: March 2007

Researchers have long debated whether adopted youth manifest disproportionate levels of psychological dysfunction compared with non‐adopted youth. Yet, missing from the debate has been a clear understanding of the specific subgroups of adopted youth who may develop behaviour problems and of the risk factors associated with various vulnerable populations. This longitudinal study examined one subpopulation of adopted youth – former foster children – in order to determine their immediate and long‐term functioning, particularly in comparison with their adopted non‐foster care peers. The central goal of this study was to ascertain the prevalence of behavioural problems in adopted foster youth compared with adopted non‐foster youth and to chart the longitudinal course of their behavioural problems. Participants included adopted foster youth (n = 293) and adopted non‐foster youth (n = 312) from a statewide sample of adopted youth, aged 2–18 years. Data were collected from the adoptive parents at approximately 2, 4 and 8 years after adoption. Adoptive parents rated youths’ functioning with the Behaviour Problems Inventory. According to parental report, a striking number of the foster youth displayed behaviour problems, although the non‐foster care group of children also displayed noteworthy levels of problem behaviours. The rates of behaviour problems in both groups far exceed what is observed in the general population of children.
Achievement of immune tolerance in a patient with haemophilia B and inhibitory antibodies, complicated by an anaphylactoid reaction
Authors: CURRY N. S. , MISBAH S. A. , GIANGRANDE P. L. F. , KEELING D. M.
Published: March 2007

Summary.  We describe a young boy with severe haemophilia B who developed inhibitory antibodies and an anaphylactoid reaction to factor IX. Immune tolerance was achieved by desensitisation with escalating doses of factor IX followed by the Malmö regimen.
Liver injury is associated with enhanced regulatory T‐cell activity in patients with chronic hepatitis B
Authors: Lin C.‐Y. , Tsai M.‐C. , Huang C.‐T. , Hsu C.‐W. , Tseng S.‐C. , Tsai I.‐F. , Chen Y.‐C. , Yeh C.‐T. , Sheen I.‐S. , Chien R.‐N.
Published: March 2007

Summary.  Chronic hepatitis B virus (HBV) infection is associated with impairment of HBV‐specific immune responses. Recently, it has been shown that regulatory T (Treg) cells downregulate HBV‐specific immune responses but their role in chronic hepatitis B is still controversial. We hypothesized that liver injury enhances the influence of Treg cells on HBV‐specific immune responses. The frequency of Treg cell and the in vitro expansion of HBV‐specific CD8+ T cell detected by the tetramer method were investigated in 79 patients with chronic hepatitis B. Thirty‐three healthy volunteers were enrolled to measure the frequency of Treg cell as controls. The results showed that in chronic hepatitis B cases, the frequency of Treg cells in peripheral blood was significantly higher than that in normal volunteers. The higher level of serum transaminase was associated with higher frequency of Treg cells, which both had a linear correlation relationship. HBV‐DNA level, HBe status, age and sex had no statistical association with Treg cell frequency. Furthermore, in patients with higher serum transaminase levels, the expansion of HBV‐specific CD8+ T cells was higher after removal of Treg cells when compared with patients with lower serum transaminase levels. In conclusion, our data indicate a significant association between serum transaminase level and frequency/activity of Treg cells. Based on this observation, we propose that liver‐injury enhances Treg cell frequency/activity in chronic hepatitis B patients.
Fulminant liver failure from acute autochthonous hepatitis E in France: description of seven patients with acute hepatitis E and encephalopathy
Authors: Péron J. M. , Bureau C. , Poirson H. , Mansuy J. M. , Alric L. , Selves J. , Dupuis E. , Izopet J. , Vinel J. P.
Published: March 2007

Summary.  Fulminant hepatitis E has not been well characterized in industrialized countries. The aim of this study was to prospectively describe patients with acute hepatitis E presenting as fulminant hepatic failure, i.e. with encephalopathy and prothrombin index <50%. Between February 1997 and April 2005, seven patients with encephalopathy were diagnosed with acute hepatitis E using viral RNA detection. These patients were compared with 33 patients diagnosed with a mild form (absence of encephalopathy) of acute hepatitis E during the same time period. Patients were 65 ± 11 years old. Five were active drinkers and six had chronic liver disease. All hepatitis E virus sequences evaluated (5/7) were of genotype 3. All patients but two died (71%). Four patients had no travel history. When compared with patients with a mild form of acute hepatitis E, active alcohol abuse and chronic liver disease were more frequent in patients with the severe form. Duration of hospitalization was longer. Aspartate transferase and bilirubin levels were significantly higher. Prothrombin index and accelerin levels were lower and death was more frequent. Acute nontravel‐associated hepatitis E can appear as fulminant hepatitis with encephalopathy and coagulation disorders. Prognosis is severe and this may be due to the age at which it occurs and frequent underlying chronic liver disease.
The effect of temperature on glutathione S‐transferase activity and glutathione content in Alopecurus myosuroides (black grass) biotypes susceptible and resistant to herbicides
Authors: MILNER L J , READE J P H , COBB A H
Published: March 2007

Herbicide‐resistant populations of Alopecurus myosuroides (black grass) have become widespread throughout the UK since the early 1980s. Previous observations in this laboratory have demonstrated that natural climatic fluctuations caused increases in endogenous glutathione S‐transferase (GST) enzyme activity in A. myosuroides plants as they mature, which is thought to be linked to herbicide resistance in this species. The present study has investigated the effects of plant growth at 10°C and 25°C, and reports GST specific activity and glutathione (GSH) pool size in resistant and susceptible A. myosuroides biotypes. Findings demonstrate differences in GST activity between resistant and susceptible populations, which are transient at lower growth temperatures. The GSH pool size was elevated at lower growth temperature in both biotypes. We speculate that these endogenous responses are part of a natural mechanism of acclimation to environmental change in this species and suggest that resistant plants are more able to adapt to environmental stress, as indicated in this instance by temperature change. These observations imply that the control of resistant A. myosuroides by graminicides may be more effective when applied at lower temperatures and at earlier growth stages.
Farm Scale Evaluations of herbicide‐tolerant crops: assessment of within‐field variation and sampling methodology for arable weeds
Authors: CLARK S J , ROTHERY P , PERRY J N , HEARD M S
Published: March 2007

The Farm Scale Evaluations (FSEs) of genetically modified herbicide‐tolerant crops (GMHT) compared the effects of conventional and GMHT crop management regimes on weed densities. Weeds were sampled in quadrats at 5 distances along 12 transects systematically arranged within experimental half‐field treatment units. Weed densities declined with increasing distance from field margins. Random variation within transects was about 80% of the total within‐half‐field variation, i.e. relatively large variation at a small scale. The spatial autocorrelation between counts on the same transect declined as the distance between quadrats increased. Sampling schemes with fewer distances along transects required more transects but fewer quadrats to achieve similar precision as the 5‐distance scheme; on average 32 quadrats were sufficient. The frequency of detection of treatment effects (5% level) was little affected by using six or even three transects (30 and 15 quadrats respectively). However, the use of the 12 transects greatly improved the detection of treatment effects at 1% and 0.1% levels. The effectiveness of the reduced schemes for detecting differences between treatments (5% level) with as few as three transects compared with 12, reflects, in part, the relatively large treatment effects (e.g. 1.5‐fold or greater), which emerged for many of the sampling occasions. The FSEs provide an unusually extensive data set. Both the data and the methodology developed for their design and analysis are valuable for the planning of future weed sampling schemes.
Fertilisation and weed control effects on yield and weeds in durum wheat grown under rain‐fed conditions in a Mediterranean climate
Authors: GARCÍA‐MARTÍN A , LÓPEZ‐BELLIDO RJ , COLETO JM
Published: March 2007

Summary A field study was undertaken to examine the effect of fertiliser type and weed control system on grain yield, yield components and weed population in durum wheat (Triticum turgidum. var. durum) grown in a 4‐year rotation [bare fallow–barley (Hordeum vulgare)–vetch (Vicia sativa)–wheat]. Fertilisation treatments were: no fertilisation, organic fertilisation with 2500 kg ha−1 of compost (sheep manure and cereal straw) and chemical fertilisation with 100–60–60 kg ha−1 of NPK. Weed‐control treatments were: no control, herbicide, harrowing with long‐flex spring tines and strip sowing with inter‐row hoeing. Chemical fertilisation increased grain yield with respect to the other treatments, amongst which no significant differences were noted. Weed‐control systems afforded no improvement in yield compared with controls; indeed, yields obtained using inter‐row hoeing were lower. The weed population consisted of a large variety of species, of which the most important were Convolvulus arvensis and Polygonum aviculare. Application of weed‐control systems reduced weed density. Herbicide was the most effective, reducing weed biomass by 80%, whilst harrowing and hoeing reduced weed biomass by 40% and 52% respectively. Inter‐row hoeing does not appear to be a viable alternative to herbicides, when used as the sole weed control method in a non‐diverse cropping system in Mediterranean climates. The lack of response to compost suggests a need for further long‐term research.
Characterisation of a triazine‐resistant biotype of Bromus tectorum found in Spain
Authors: MENENDEZ J , GONZALEZ‐GUTIERREZ J , DE PRADO R
Published: March 2007

A population of Bromus tectorum infesting an olive grove at Córdoba (Spain) survived simazine use rates of 3.0 kg a.i. ha−1 over two consecutive years. Non‐tillage olive monoculture and two annual simazine applications had been carried out for 10 years. The resistant biotype showed a higher ED50 value (7.3 kg a.i. ha−1) than that of the susceptible control (0.1 kg a.i. ha−1), a 73‐fold increase in herbicide tolerance. The use of fluorescence, Hill reaction, absorption, translocation and metabolism assays showed that simazine resistance in this biotype was caused by a modification of the herbicide target site, since chloroplasts from the resistant biotype of B. tectorum were more than 300 times less sensitive to simazine than those from the susceptible biotype. In addition, non‐treated resistant plants of B. tectorum displayed a significant reduction in the QA to QB electron transfer rate when compared with the susceptible biotype, a characteristic that has been linked to several mutations in the protein D1 conferring resistance to PS II inhibiting herbicides. Resistant plants showed cross‐resistance to other groups of triazine herbicides with the hierarchy of resistance level being methoxy‐s‐triazines ≥chloro‐s‐triazines > methylthio‐s‐triazines > cis‐triazines. The results indicate a naturally occurring target‐site point mutation is responsible for conferring resistance to triazine herbicides. This represents the first documented report of target site triazine resistance in this downy brome biotype.
Babesia as a complication of immunosuppression following pig‐to‐baboon heart transplantation
Authors: Ezzelarab Mohamed , Yeh Peter , Wagner Robert , Cooper David K. C.
Published: March 2007

Abstract:  We report a baboon that developed anemia, leukocytosis, fever, and anorexia while immunosuppressed following a pig heart transplant. Blood smears indicated babesia infection of the erythrocytes, and this was confirmed by polymerase chain reaction. A 1‐week course of treatment with doxycycline successfully eradicated the organism. Babesia, a widespread blood parasite that can infect humans, has been reported to be present in the erythrocytes of approximately a third of baboons housed in facilities in the USA, without overt signs of infection. Immunosuppression can reduce the host's immune system, and result in proliferation of the parasite, leading to hemolysis and other features of infection, sometimes with fatal outcome.