2,258 research outputs found
Total organic carbon, total nitrogen and chemical characteristics of an haplic cambisol after biochar incorporation
Biochar
has
been
used
as
a
soil
conditioner
to
increase
the
soil
organic
carbon
content
and
to
improve
the
soil
chemical
characteristics.
However,
the
effect
of
biochar
on
soil
is
still
not
clear
and
the
soil
type
and
biochar
composition
should
also
play
an
important
role.
In
this
context,
the
main
objective
of
this
work
was
to
evaluate
the
effect
of
biochar
application
on
the
organic
carbon
(C)
content
and
on
chemical
characteristics
of
subtropical
Cambisol.
The
field
experiment
was
located
at
the
State
University
of
Centro
‐
Oeste
in
Irati,
Brazil,
and
the
soil
was
classified
as
an
Haplic
Cambisol
(Embrapa,
1999).
The
applied
biochar
was
composed
mainly
by
fine
residues
(
70%
<
2mm
)
of
an
eucalyptus
biochar
that
was
a
waste
of
the
local
steel
industry.
In
February
2010,
four
increasing
doses
of
biochar
were
applied
to
the
soil
(T1
‐
0
t
ha
‐
1
;
T2
‐
10
t
ha
‐
1
;
T3
‐
20
t
ha
‐
1
and
T4
‐
40
t
ha
‐
1
)
with
four
replicates.
Soil
samples
were
composed
by
three
subsamples
collected
within
each
plot.
Biochar
was
applied
on
the
soil
surface
and
thereafter
it
was
incorporated
into
a
0
‐
10
cm
soil
depth
with
an
harrow.
Soil
samples
were
collected
in
September
2011
at
four
soil
depths:
0
‐
5;
5
‐
10;
10
‐
20
and
20
‐
30
cm.
The
samples
were
air
dried
and
passed
through
a
2
mm
sieve.
Soil
C
and
nitrogen
(N)
contents
were
determined
by
dry
combustion
and
the
soil
characteristics
assessed
were:
pH
in
water,
available
P,
exchangeable
K,
Ca,
Mg
and
Al,
potential
acidity
(H
+
Al),
cation
exchange
capacity
(CEC),
effective
cation
exchange
capacity
(ECEC)
and
base
saturation
(V%)
(Tedesco
et
al.,
1995).
The
mean
values
were
compared
using
SAS
software
(Tukey
10%).
The
main
alterations
in
soil
characteristics
were
observed
in
the
superficial
depth
(0
‐
5
cm)
(Table
1)
probably
due
to
the
permanence
of
the
biochar
fine
particles
at
the
soil
surface.
In
this
layer,
the
application
of
40
t
ha
‐
1
of
biochar
(treatment
T4)
increased
in
15.5
g
kg
‐
1
the
C
content
in
comparison
to
treatment
T1.
The
treatments
T2
and
T3
also
increased
the
C
content,
but
the
differences
were
not
significant.
N
content
was
not
affected
by
biochar
application.
The
highest
dose
of
biochar
(treatment
T4)
promoted
an
increase
of
the
C/N
ratio
from
12
to
16
at
the
0
‐
5
cm
depth.
Treatment
T4
also
increased
the
soil
pH
value
in
comparison
to
treatment
T1.
In
addition,
the
contents
of
available
P,
exchangeable
K
and
Ca
where
higher
under
treatment
T4
in
comparison
to
treatment
T1
(Table
1).
In
opposition,
exchangeable
Mg
content,
Al+H,
V%
and
CEC
were
not
altered
by
any
treatment,
but
T4
increased
the
ECEC
in
3.1
cmol
c
dm
‐
3
in
comparison
to
T1.
The
results
observed
are
probably
due
the
high
C
and
ash
(26,5%)
contents
of
biochar.
A
contribution
of
the
functional
groups
on
the
surface
of
the
biochar
to
the
ECEC
should
not
be
excluded
(Sparkes
&
Stoutjesdijk,
2011).
Our
results
indicate
that
after
two
years
of
biochar
application
an
increase
of
soil
organic
carbon
and
a
positive
impact
on
the
soil
chemical
characteristics
at
the
soil
surface
were
attained,
but
only
with
the
highest
tested
dose
(40
t
ha
‐
1
)
.Peer reviewe
Pentoxifylline, tocopherol, and sequestrectomy are effective for the management of advanced osteoradionecrosis of the jaws—a case series
Background:
The aim of the present study was to evaluate the efficacy of pentoxifylline and tocopherol for the management of osteoradionecrosis of the jaws. /
Methods:
Twenty-five patients diagnosed with osteoradionecrosis of the jaws treated with pentoxifylline 400 mg + tocopherol 400 mg three times daily (tid) were evaluated. Clinical records and image tests were reviewed. All patients were previously submitted to head and neck radiation therapy and presented with a clinical and radiographic diagnosis of osteoradionecrosis of the jaws. /
Results:
Following therapy with pentoxifylline and tocopherol, 76% (19/25) of the patients showed complete mucosal healing, in which 47.3% (9/19) did not undergo sequestrectomy. From this particular group, 77.7% (7/9) were in stage I and 33.3% (3/9) used the protocol for up to 3 months. Among those who underwent to sequestrectomy, complete mucosal healing was observed in 52.7% (10/19). Among these, 60% (6/10) were in stage I and 100% of the patients were using the protocol for more than 3 months. In all other patients, partial healing of the mucosa was observed since they presented advanced disease. These represented 24% of the sample (6/25), 66.6% (4/6) were in stage III, and 60% (4/6) used the protocol for over 6 months. /
Conclusion:
Pentoxifylline and tocopherol may provide effective management of osteoradionecrosis of the jaws, and the association with sequestrectomy may avoid major surgical procedures
Search for CP violation in D0 and D+ decays
A high statistics sample of photoproduced charm particles from the FOCUS
(E831) experiment at Fermilab has been used to search for CP violation in the
Cabibbo suppressed decay modes D+ to K-K+pi+, D0 to K-K+ and D0 to pi-pi+. We
have measured the following CP asymmetry parameters: A_CP(K-K+pi+) = +0.006 +/-
0.011 +/- 0.005, A_CP(K-K+) = -0.001 +/- 0.022 +/- 0.015 and A_CP(pi-pi+) =
+0.048 +/- 0.039 +/- 0.025 where the first error is statistical and the second
error is systematic. These asymmetries are consistent with zero with smaller
errors than previous measurements.Comment: 12 pages, 4 figure
A Study of D0 --> K0(S) K0(S) X Decay Channels
Using data from the FOCUS experiment (FNAL-E831), we report on the decay of
mesons into final states containing more than one . We present
evidence for two Cabibbo favored decay modes, and
, and measure their combined branching fraction
relative to to be = 0.0106
0.0019 0.0010. Further, we report new measurements of
=
0.0179 0.0027 0.0026, = 0.0144 0.0032 0.0016,
and = 0.0208 0.0035 0.0021 where the first error is
statistical and the second is systematic.Comment: 11 pages, 3 figures, typos correcte
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