41 research outputs found
Light absorption properties of laboratory-generated tar ball particles
Tar balls (TBs) are a specific particle type that is
abundant in the global troposphere, in particular in biomass
smoke plumes. These particles belong to the family of atmospheric
brown carbon (BrC), which can absorb light in the
visible range of the solar spectrum. Albeit TBs are typically
present as individual particles in biomass smoke plumes,
their absorption properties have been only indirectly inferred
from field observations or calculations based on their electron
energy-loss spectra. This is because in biomass smoke
TBs coexist with various other particle types (e.g., organic
particles with inorganic inclusions and soot, the latter emitted
mainly during flaming conditions) from which they cannot
be physically separated; thus, a direct experimental determination
of their absorption properties is not feasible. Very
recently we have demonstrated that TBs can be generated
in the laboratory from droplets of wood tar that resemble
atmospheric TBs in all of their observed properties. As a
follow-up study, we have installed on-line instruments to
our laboratory set-up, which generate pure TB particles to
measure the absorption and scattering, as well as the size
distribution of the particles. In addition, samples were collected
for transmission electron microscopy (TEM) and total
carbon (TC) analysis. The effects of experimental parameters
were also studied. The mass absorption coefficients of
the laboratory-generated TBs were found to be in the range
of 0.8–3.0m2
Atmospheric tar balls: aged primary droplets from biomass burning?
Atmospheric tar balls are particles of special morphology and composition
that are fairly abundant in the plumes of biomass smoke. These particles
form a specific subset of brown carbon (BrC) which has been shown to play a
significant role in atmospheric shortwave absorption and, by extension, climate
forcing. Here we suggest that tar balls are produced by the direct emission
of liquid tar droplets followed by heat transformation upon biomass burning.
For the first time in atmospheric chemistry we generated tar-ball particles
from liquid tar obtained previously by dry distillation of wood in an
all-glass apparatus in the laboratory with the total exclusion of flame
processes. The particles were perfectly spherical with a mean optical
diameter of 300 nm, refractory, externally mixed, and homogeneous in the
contrast of the transmission electron microscopy (TEM) images.
They lacked any graphene-like microstructure and
exhibited a mean carbon-to-oxygen ratio of 10. All of the observed
characteristics of laboratory-generated particles were very similar to those
reported for atmospheric tar-ball particles in the literature, strongly
supporting our hypothesis regarding the formation mechanism of atmospheric
tar-ball particles
Metasztatikus ovariumcarcinoma kemoterápiás kezelése nyolc éven át | Chemotherapeutic treatment of metastatic ovarian cancer for 8 years. Case report
Absztrakt
A 48 éves nőbetegnél 2006-ban pleuralis folyadék, hasi fájdalom és ascites miatt
indult kivizsgálás során a panaszok és tünetek hátterében előrehaladott stádiumú
ovariumcarcinoma igazolódott, amely miatt hysterectomia és kétoldali
adnexectomia történt. A szövettani vizsgálat FIGO IIIB stádiumú papillaris
adenocarcinomát mutatott. Posztoperatívan a standard, 6 ciklus taxol-carboplatin
kezelésben részesült. 2008-ban retroperitonealis nyirokcsomó-metasztázisok miatt
reindukciós taxol-carboplatin kezelés indult, azonban progresszió miatt hamar
kezelésváltás vált szükségessé. Ezt követően még hatféle kemo- vagy biológiai
terápiás kezelésben részesült, köztük a hetedik vonalban off-label megigényelt
FOLFOX-4-kezelés. A FOLFOX-4-terápia mellett is jelentős regresszió igazolódott,
a progressziómentes túlélés mintegy 9 hónap volt. A váltott kezelések során a
beteg mindvégig kielégítő általános állapotban volt, lényegében tolerálható
mellékhatások mellett. A teljes túlélés 98 hónapnak bizonyult. Az eset jól
mutatja a személyre szabott, váltott kemoterápiás kezelés sikerességét már a
diagnózis idején is előrehaladott állapotú petefészek-daganatnál is. Orv.
Hetil., 2016, 157(44), 1769–1773.
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Abstract
The authors present the history of a 48-year-old woman, who developed pleural
effusion, abdominal pain and ascites due to an advanced ovarian cancer. She
underwent hysterectomy and bilateral adnexectomy in 2006, and histology revealed
FIGO IIIB papillary adenocarcinoma. After surgery the patient recieved the
standard, 6 cycle taxol-carboplatin therapy. Taxol-carboplatin therapy was
reinitiated because of retroperitoneal lymph node metastases in 2008, but soon
the therapy had to be changed because of progression. Thereafter the patient
recieved 6 different types of chemo- and biological therapy including the
off-label FOLFOX-4 treatment at seventh line. Significant regression in response
to FOLFOX-4 therapy was confirmed with a progression free survival of about 9
months. The general condition of the patient was satisfying during the whole
chemotherapy, and the side effects were tolerable. The overall survival was 98
months. This case history is a good example for the success of individualized,
long term chemotherapy even if ovarian tumor diagnosed at advanced stage as it
happened in this case. Orv. Hetil., 2016, 157(44),
1769–1773