Thermophysical properties of phytosterols Korshunov, A. O.; Markin, A. V.; Kushnir, S. R. ...
Journal of thermal analysis and calorimetry,
12/2022, Letnik:
147, Številka:
24
Journal Article
Recenzirano
In the present research, the thermophysical properties of phytosterols were investigated by thermogravimetry (TG) and differential scanning calorimetry (DSC) in the range of 300–800 K. As a result, ...the areas of their thermal stability were established. The thermodynamic characteristics of melting and crystallization have been determined. For one of the samples, the specific heat was studied in the range 260–570 K. Comparison of the present results with the data available in the literature was carried out. The dependence of thermophysical properties on the composition and nature of phytosterols has been concluded.
The double polarization observable E and the helicity dependent cross sections σ_{1/2} and σ_{3/2} were measured for η photoproduction from quasifree protons and neutrons. The circularly polarized ...tagged photon beam of the A2 experiment at the Mainz MAMI accelerator was used in combination with a longitudinally polarized deuterated butanol target. The almost 4π detector setup of the Crystal Ball and TAPS is ideally suited to detect the recoil nucleons and the decay photons from η→2γ and η→3π^{0}. The results show that the narrow structure previously observed in η photoproduction from the neutron is only apparent in σ_{1/2} and hence, most likely related to a spin-1/2 amplitude. Nucleon resonances that contribute to this partial wave in η production are only N 1/2^{-} (S_{11}) and N 1/2^{+} (P_{11}). Furthermore, the extracted Legendre coefficients of the angular distributions for σ_{1/2} are in good agreement with recent reaction model predictions assuming a narrow resonance in the P_{11} wave as the origin of this structure.
Primary mucosal melanoma of the head and neck (MMHN) comprises approximately 1% of all malignant melanomas. It presents more commonly in an elderly population and has no significant gender ...predominance. Given its rarity, most evidence of the causes, behavior, and treatment approaches for MMHN originates from isolated case reports and retrospective series. Between 1945 and 2011, at least 1951 cases of MMHN have been reported in the literature. Despite numerous technological developments in surgery and radiation therapy, as well as advances in systemic modalities, MMHN is an aggressive malignancy with a very poor prognosis. Complete surgical excision with clear margins remains the primary treatment modality. Adjuvant postoperative radiation therapy may improve locoregional control but does not appear to affect survival. Definitive particle radiation therapy promises to provide high rates of local control for nonoperable patients. Recent molecular evidence suggests that proto-oncogene KIT aberrations in a subset of mucosal melanomas may represent a potential diagnostic value and serve as a therapeutic target for tyrosine kinase inhibitors in an adjuvant setting for patients with advanced MMHN.
Abstract
This paper presents a phenomenological analysis of thermodynamic parameters of a pulsed supersonic gas jet in a conical nozzle. Conditions have been found out for the condensation and ...formation of large krypton clusters resulting from phase transitions during adiabatic expansion of gas through the nozzle into vacuum. We have identified the phase state of the large clusters (submicron droplets consisting of ∼10
7
monomers) forming in the jet and obtained a high yield of X-rays from a cluster nanoplasma produced by femtosecond laser pulses of relativistic intensity
I
. It has been shown that, at
I
≈ 3 × 10
18
W cm
−2
, a nanoplasma consisting of large krypton clusters emits a broadband X-ray spectrum in the range 5 – 100 keV. The integrated laser to X-ray energy conversion efficiency achieved is ∼10
−5
(400 nJ), and the efficiency of characteristic K
α
line (12.6 keV) generation is ∼1.5 × 10
−6
(68 nJ), which corresponds to a quantum yield of ∼3 × 10
8
photons s
−1
(4
π
)
−1
, with a contrast of ∼25 relative to bremsstrahlung background.
AbstractPurposeDiffuse intrinsic pontine glioma (DIPG) is the most aggressive primary pediatric brain tumor, with <10% of children surviving 2 years. Radiation therapy (RT) remains the mainstay of ...treatment, but there is a great clinical need for improvements and advancements in treatment strategies. The aim of this systematic review was to identify all available studies in which RT was used to treat patients with DIPG.Methods and MaterialsA literature search for studies published up to March 10, 2018 was conducted using the PubMed database. We identified 384 articles using search items “diffuse intrinsic pontine glioma” and 221 articles using search items “diffuse brainstem glioma radiotherapy.” Included studies were prospective and retrospective series that reported outcomes of DIPG treatment with RT.ResultsWe identified 49 studies (1286 patients) using upfront conventionally fractionated RT, 5 studies (92 patients) using hypofractionated RT, and 8 studies (348 patients) using hyperfractionated RT. The mean median overall survival (OS) was 12.0 months, 10.2 months, and 7.9 months in patients who received conventional, hyperfractionated, and hypofractionated RT regimens, respectively. Patients undergoing radiosensitizing therapy had a mean median OS of 11.5 months, and patients who did not receive concomitant systemic therapy had an OS of 9.4 months. In patients who received salvage RT, the mean median OS from initial diagnosis was 16.3 months.ConclusionsAs one of the largest systematic reviews examining RT for DIPG, this report may serve as a useful tool to help clinicians choose the most appropriate treatment approach, while also providing a platform for future investigations into the utility of RT and systemic therapy.
The extractable fractions of organic matter (OM) differing in their mobility
—
water-extractable organic matter, labile humic substances, and humic substances
—
have been isolated from ...different-sized aggregates of a typical chernozem (Haplic Chernozem (Loamic, Pachic)). The first two fractions characterize the active OM pool, and the latter fraction characterizes the slow OM pool. Overall, the extractable OM fractions make it possible to assess the content and qualitative composition of the active and slow OM pools and, in an indirect manner, of the passive OM pool. The content of dissolved organic carbon in the extracts is used to quantify the yield of fractions, and the spectral characteristics of light absorption in the ultraviolet and visible ranges attest to their qualitative composition. The main attention is focused on the OM recovery in the chernozems after an extreme regime (permanent tilled fallow) and on the differences in the OM of soil aggregates in dependence on their size. A large part of plant residues entering the soil during the recovery of the chernozem after the extreme conditions of tilled fallow is fixed in the passive OM pool. The qualitative composition of active pools is restored much faster than their quantity typical of the undisturbed cenoses. The optical descriptors
E
2
/
E
3
of labile humic substances and
E
4
/
E
6
of humic substances significantly depends on the size of aggregates.
Summary Background Russian adults have extraordinarily high rates of premature death. Retrospective enquiries to the families of about 50 000 deceased Russians had found excess vodka use among those ...dying from external causes (accident, suicide, violence) and eight particular disease groupings. We now seek prospective evidence of these associations. Methods In three Russian cities (Barnaul, Byisk, and Tomsk), we interviewed 200 000 adults during 1999–2008 (with 12 000 re-interviewed some years later) and followed them until 2010 for cause-specific mortality. In 151 000 with no previous disease and some follow-up at ages 35–74 years, Poisson regression (adjusted for age at risk, amount smoked, education, and city) was used to calculate the relative risks associating vodka consumption with mortality. We have combined these relative risks with age-specific death rates to get 20-year absolute risks. Findings Among 57 361 male smokers with no previous disease, the estimated 20-year risks of death at ages 35–54 years were 16% (95% CI 15–17) for those who reported consuming less than a bottle of vodka per week at baseline, 20% (18–22) for those consuming 1–2·9 bottles per week, and 35% (31–39) for those consuming three or more bottles per week; trend p<0·0001. The corresponding risks of death at ages 55–74 years were 50% (48–52) for those who reported consuming less than a bottle of vodka per week at baseline, 54% (51–57) for those consuming 1–2·9 bottles per week, and 64% (59–69) for those consuming three or more bottles per week; trend p<0·0001. In both age ranges most of the excess mortality in heavier drinkers was from external causes or the eight disease groupings strongly associated with alcohol in the retrospective enquiries. Self-reported drinking fluctuated; of the men who reported drinking three or more bottles of vodka per week who were reinterviewed a few years later, about half (185 of 321) then reported drinking less than one bottle per week. Such fluctuations must have substantially attenuated the apparent hazards of heavy drinking in this study, yet self-reported vodka use at baseline still strongly predicted risk. Among male non-smokers and among females, self-reported heavy drinking was uncommon, but seemed to involve similar absolute excess risks. Interpretation This large prospective study strongly reinforces other evidence that vodka is a major cause of the high risk of premature death in Russian adults. Funding UK Medical Research Council, British Heart Foundation, Cancer Research UK, European Union, WHO International Agency for Research on Cancer.
The structure of
N
-(2,3-dihydroxy-4-iodo-2,3-dimethylbutyl)trifluoroacetamide and its dimers has been studied in the crystal, solution, and gas phase by means of IR spectroscopy and quantum chemical ...simulation at the DFT level. The obtained data have been compared to the data of X-ray diffraction analysis.
One reason for the high mortality rate from bowel cancer is the formation of metastases, and effective animal models of cancer are needed to analyze the mechanism of their development. To create such ...models of metastasis, we carried out orthotopic inoculation of mice with CT26 mouse colorectal cancer cells containing the luciferase gene into the submucosal region of the caecum of animals. Mice were sacrificed 30 days after inoculation, and the presence of metastases in organs was determined based on the analysis of the amount of messenger RNA of the luciferase gene using real-time polymerase chain reaction. It has been established that after orthotopic injection of CT26 colorectal cancer cells in experimental animals, metastases are found not only in the liver, but also in the lungs and spleen. Such data were obtained for the first time and allow us to consider the protocol that we used for modeling the process of colorectal cancer metastasis in mice.
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