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. | 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