MAC Values Research Articles

The impact of Fe2O3 on the dispersion parameters and gamma/fast neutron shielding characteristics of lithium borosilicate glasses

50.4B2O3 – 30SiO2 – (19.6−x) Li2O – x Fe2O3, x = (0 ≤ x ≤ 2 mol%) glasses are studied for optical, and radiation characteristics. XRD was used to determine the structural characteristics of the proposed glasses. The chief objective of this article is to fabricate high density samples with replacing Li2O with Fe2O3 to investigate the optics and radiation characteristics. Density, and refractive index of fabricated glasses have all been found to be higher. As the concentration of Fe2O3 rises, energy bandgap reduces. The radiation shielding characteristics were examined using Phy-X/PSD. Increases in the Fe2O3 ratio have a positive impact on MAC values. These results reveal G 5 as the best candidate for shielding against gamma radiation.

Anesthesia Methods in Pregnant Women: A Review Study

Background: Manage and deal with the pregnant patient undergoing anesthesia for surgical non-obstructed surgery, assess the effects of non-obstetric surgeries on both fetus and mother during pregnancy, and measures to prevent it. Methods: A review search study was currently managed in PubMed, MEDLINE, Embase, Science gate, Elsevier, Scientific report, Google Scholar, and Cochrane Evidence-Based Medicine Reviews, after obtaining approval from the ethics committee of Tehran University of Medical Sciences. All the reviews identified were restricted to human studies and available in English. Results: Elective surgery ideally should be avoided during pregnancy while emergency surgery should proceed with consideration for the anesthetic implications of the altered physiology of pregnancy. Caution must be taken during anesthetic application and Airway management. Conclusion: Pre-oxygenation is essential and consider the rapid-sequence induction accompanied with cricoid pressure to lower the incidence of aspiration. Lower MAC values of the volatile anesthetic should be used and medications titrated to preferably produce beneficial effects only.

Efficacy of Oral Clonidine as Premedication on Intraoperative Bleeding and Consumption of Inhalational Agent in Patients Undergoing Functional Endoscopic Sinus Surgery

Aim: To study the efficacy of oral clonidine on intraoperative bleeding and consumption of inhalational agent in patients undergoing FESS under general anesthesia.
 Study Design: Prospective, comparative observational study.
 Place and Duration of Study: Department of Anesthesiology, AVBRH, from June 2020 to May 2021.
 Methodology: A total of 30 patients fulfilling inclusion criteria scheduled for FESS were randomly allocated into 2 groups of 15 each; GROUP C (Clonidine group, n=15) who received tab clonidine 5 mcg/kg, 90 minutes before surgery and GROUP M (Multivitamin group, n=15) who received multivitamin tablet. Mean ± standard deviation (SD) or absolute values were used to indicate data; comparison of qualitative data were done using Chi-square test and Fisher’s exact test and quantitative variables using the student ‘t’ Test. P value < 0.05 was taken as statistically significant.
 Results: Bleeding was considerably less in the group C [1.65 ± 0.4] as compared to group M [2.20 ± 0.6] and is statistically significant [ P value = 0.006]. The mean MAC value (%) of sevoflurane consumption is lesser in the group C [1.25 ±0.25] than the group M [1.30 ±0.20] but not statistically significant (P value = 0.55). The mean dose (microgram) of fentanyl requirement was more in group M [ 120 ±20] than the group C [100 ± 25] and this was statistically significant (P value = 0.02).
 Conclusion: Oral Clonidine can be used as an excellent premedication and provides cost effective method to attain controlled hypotension as there is lesser requirement of costly inhalational agent and other analgesic drugs. Also, it maintains better hemodynamic stability with fewer side effects.

Estimates of mass absorption cross sections of black carbon for filter-based absorption photometers in the Arctic

Abstract. Long-term measurements of atmospheric mass concentrations of black carbon (BC) are needed to investigate changes in its emission, transport, and deposition. However, depending on instrumentation, parameters related to BC such as aerosol absorption coefficient (babs) have been measured instead. Most ground-based measurements of babs in the Arctic have been made by filter-based absorption photometers, including particle soot absorption photometers (PSAPs), continuous light absorption photometers (CLAPs), Aethalometers, and multi-angle absorption photometers (MAAPs). The measured babs can be converted to mass concentrations of BC (MBC) by assuming the value of the mass absorption cross section (MAC; MBC= babs/ MAC). However, the accuracy of conversion of babs to MBC has not been adequately assessed. Here, we introduce a systematic method for deriving MAC values from babs measured by these instruments and independently measured MBC. In this method, MBC was measured with a filter-based absorption photometer with a heated inlet (COSMOS). COSMOS-derived MBC (MBC (COSMOS)) is traceable to a rigorously calibrated single particle soot photometer (SP2), and the absolute accuracy of MBC (COSMOS) has been demonstrated previously to be about 15 % in Asia and the Arctic. The necessary conditions for application of this method are a high correlation of the measured babs with independently measured MBC and long-term stability of the regression slope, which is denoted as MACcor (MAC derived from the correlation). In general, babs–MBC (COSMOS) correlations were high (r2= 0.76–0.95 for hourly data) at Alert in Canada, Ny-Ålesund in Svalbard, Barrow (NOAA Barrow Observatory) in Alaska, Pallastunturi in Finland, and Fukue in Japan and stable for up to 10 years. We successfully estimated MACcor values (10.8–15.1 m2 g−1 at a wavelength of 550 nm for hourly data) for these instruments, and these MACcor values can be used to obtain error-constrained estimates of MBC from babs measured at these sites even in the past, when COSMOS measurements were not made. Because the absolute values of MBC at these Arctic sites estimated by this method are consistent with each other, they are applicable to the study of spatial and temporal variation in MBC in the Arctic and to evaluation of the performance of numerical model calculations.

Source attribution of black and Brown carbon near-UV light absorption in Beijing, China and the impact of regional air-mass transport

Black and Brown Carbon (BC, BrC) are key parameters of climate forcing, yet significant challenges exist assigning emission source contributions to light-absorption by carbonaceous aerosols. Additionally, BC and BrC emissions add to extreme air pollution events in Chinese mega-cities, which harm human health and detract from the natural and built environment. To address these concerns, the ability to estimate atmospheric light absorption related to emission sources and global inventories is a highly valuable tool for climate modelers and policy makers. Three months of BC and BrC data was collected using an Aethalometer in parallel to PM2.5 filter sampling during a stringent emission controls period and post controls period, including during the regional heating season. In this study reconstructed 370 nm wavelength absorption was calculated by applying source specific Mass Absorption Cross-Sections to PMF apportioned EC and OC results. Reconstructed absorption showed good agreement with the ambient measured absorption for both BC and BrC. In Beijing, the major contributor to near-UV absorption was mobile sources, which accounted for 45–54% of absorption by BC and 14–18% by BrC. BrC absorption from secondary aerosols, biomass burning, and soil dust was also estimated, with these sources contributing from 1 to 9% individually. Meteorological cluster analysis showed that air mass origin did not impact the absorption reconstruction and that the highest regional contribution to near-UV light absorption originated primarily in areas south and east of Beijing. The study shows ambient near-UV light absorption can be predicted using BC and BrC MAC values from sources. However, the current number of multi-wavelength and source specific BrC MAC values reported in the literature is limited. The reconstruction approach allows for a more robust method of assigning light absorption to source categories, allowing the expansion of aethalometer derived BrC apportionment to multiple sources, including biomass burning.

Gamma and neutron shielding properties of B4C particle reinforced Inconel 718 composites

Neutron and gamma-ray shielding properties of Inconel 718 reinforced B4C (0-25 wt%) were investigated using PSD software. Mean free path (MFP), linear and mass attenuation coefficients (LAC,MAC), tenth-value and half-value layers (TVL,HVL), effective atomic number (Zeff), exposure buildup factors (EBF), and fast neutron removal cross-sections (FNRC) values were calculated for 0.015–15 MeV. It was found that MAC and LAC increased with the decrease in the content of B4C compound by weight in Inconel 718. The EBFs were computed using G-P fitting method for 0.015–15 MeV up to the penetration depth of 40 mfp. HVL, TVL, and FNRC values were found to range between 0.018 cm and 3.6 cm, between 2.46 cm and 12.087 cm, and between 0.159 cm−1 and 0.194 cm−1, respectively. While Inconel 718 provides the maximum photon shielding property since it offered the highest values of MAC and Zeff and the lowest value of HVL, Inconel 718 with B4C(25 wt%) was observed to provide the best shielding material for neutron since it offered the highest FNRC value. The study is original in terms of several aspects; moreover, the results of the study may be used in nuclear technology, as well as other technologies including nano and space technologies.

The significant role of CeO2 content on the radiation shielding performance of Fe2O3-P2O5 glass-ceramics: Geant4 simulations study

Natural and artificial sources of radiation can be encountered in many areas of our lives. Particularly, ionizing radiation has harmful effects on humans therefore researchers look for novel materials an alternative to traditional shielding materials to protect humans. For this purpose, in this paper, newly developed glass-ceramics in the chemical form of x is between 0 and 8 mol%, were reported in terms of their gamma/neutron attenuation properties to serve for radiation shielding applications. Gamma attenuation features were investigated by using the Monte Carlo method via Geant4 toolkit. From Geant4 simulations, the coefficients of mass attenuation (denoted by μ/ρ or MAC) were extracted and then compared with those of Phy-X/PSD calculations. The MAC values (at 0.015 MeV as an example) increased from 21.029 cm2 g−1 to 24.446 cm2 g−1 as the content increased from 0 to 8 mol%. The HVL values are between 0.011–9.830 cm for CFP-0, 0.010–9.376 cm for CFP-2, 0.010–8.863 cm for CFP-4, 0.009–8.675 cm for CFP-6 and 0.009–8.424 cm for CFP-8 in energy range from 0.015–15 MeV. The Zeff values (at 1 MeV gamma energy) are 11.70, 11.84, 11.99, 12.15, and 12.30 for CFP-0, CFP-2, CFP-4, CFP-6, and CFP-8 glass-ceramics, respectively. The maximum Zeq values for the present glass-ceramics are occurred at 1 MeV with the values of 19.21, 22.69, 25.14, 27.10, and 28.73 for CFP-0, CFP-2, CFP-4, CFP-6, and CFP-8 glass-ceramics, respectively. The results show that theoretically, CFP-8 has better photon absorption features due to the higher content of among the investigated CFP ceramic glasses. Contrary to these results, there is not considerable variations between among removal cross section (RCS) for fast neutron of CFP glass ceramics with the rising of

Seasonal variations of macro-, micro-, and toxic elements in tissues of vimba bream (Vimba vimba) from the Danube River near Belgrade, Serbia.

Vimba bream (Vimba vimba) individuals were collected from the Danube River near Belgrade, from May 2016 to May 2017. Samples of muscle and liver tissue were analyzed for concentrations of 25 elements (macro-, micro-, and toxic elements) using inductively coupled plasma optical emission spectrometry (ICP-OES). For both tissues, the highest concentrations of most elements were observed in late spring/early summer (months of May and June). Majority of statistically significant correlations between elements were positive in both tissues. Contributions of Ca, K, and Mg to human diet were in a similar range. The lowest contribution of all macroelements was observed for Na, while the contribution of Se was well above the recommended dietary allowance for this element. Levels of detected elements were well below MAC values prescribed by national and international regulations. The highest value of Hg liver/muscle index (>1) was observed in August, which could indicate a higher contamination of the sampling location in that month. Se:Hg molar ratio never drops below 1, which could indicate that Hg toxicity is prevented. THQ values showed little variation thought the year and were well below the threshold of 1, with the exception of THQ for Al in May (0.92). This element also strongly affects the hazard index.

Role of Sm+3 ions on structural, optical and radiation shielding properties of lead borosilicate glasses

lead borosilicate glasses comprising samarium oxide (Sm2O3) had been developed by using melt-quenching procedure. The values of glass density became reported to enhance as Sm2O3 raise from 3.632 g/cm3 for 1 percent Sm2O3 to 3.764 g/cm3 for 6 percent Sm2O3, were attributable to the substitution of boron with lower density by samarium with higher density. The molar volume of the samples prepared was calculated from the density data. Optical absorption spectra have been reported and optical parameter values like the optical transformation, optical electronegative behavior, index of refraction, high frequency constant of dielectric, singular oscillator energy and dispersive energy have been calculated. The optical parameters were associated with the Sm2O3 ratio. Judd–Official concept has been extended to the glass absorption spectra to the model of radiative and laser properties. Judd–Official parameters (Ω2, Ω4, Ω6) were defined as Ω2 > Ω4 > Ω6 and linked to the composition of glass. Such glasses have been realized to be used as photonic devices. The maximum & least MAC values were obtained at the energies of 15 keV & 6 MeV for all Sm-Glasses. The trend of the LAC values follows the trend: (LAC)Sm1 < (LAC)Sm2 <(LAC)Sm3 <(LAC)Sm4 < (LAC)Sm5 < (LAC)Sm6. The HVL of the Sm-glasses were lower than those of ordinary concrete and RS-360. Thus, indicates that the Sm-glasses absorbs photon better than these two materials and can be used in their instead especially where space is a constrain.

Exploring the FTIR, Optical and Nuclear Radiation Shielding Properties of Samarium-Borate Glass: A Characterization through Experimental and Simulation Methods.

(Tl2O3)30-(Li2O)10-(B2O3)(60−y)-(Sm2O3)y glass system with various Sm2O3 additives (y = 0, 0.2, 0.4, 0.6) was studied in detail. The vibrational modes of the (Tl2O3)30-(Li2O)10-(B2O3)(60−y) network were active at three composition-related IR spectral peaks that differed from those mixed with Samarium (III) oxide at high wavenumber ranges. These glass samples show that their permeability increased with the Samarium (III) oxide content increase. Additionally, the electronic transition between localized states was observed in the samples. The MAC, HVL, and Zeff values for radiation shielding parameters were calculated in the energy range of 0.015–15 MeV using the FLUKA algorithm. In addition, EBF, EABF, and ΣR values were also determined for the prepared glasses. These values indicated that the parameters for shielding (MAC, HVL, Zeff, EBF, EABF, and ΣR) are dependent upon the Samarium (III) oxide content. Furthermore, the addition of Samarium (III) oxide to the examined glass samples greatly reinforced their shielding capacity against gamma photon. The findings of the current study were compared to analyses of the XCOM software, some concretes, and lead. In the experiment, it was found that the SMG0.6 glass sample was the strongest shield.

Pyrazole-Thiazole Core-Containing Analogs Exhibit Adjunctive Activity with Meropenem against Carbapenem-Resistant Enterobacteriaceae (CRE).

Pyrazole-thiazole core-containing compound KP-40 and 20 novel derivatives were designed and synthesized through traditional SAR analysis. These molecules displayed adjunctive activity with meropenem against Gram-negative bacteria evidenced by a range of fractional inhibitory concentration (FIC=0.5-0.25) and minimum adjunctive concentration (MAC=128-32 μM) values. Of this series of molecules, four compounds displayed notable adjunctive potential, with FIC and MAC values of 0.25 and 32 μM, respectively. Moreover, the solubility of these compounds was improved to an acceptable range. Further analysis using our "in house" permeation and efflux multi parameter optimization (PEMPO) algorithm revealed key physicochemical properties that may be critical for the development of active Gram-negative antibacterials. Taking PEMPO scores into consideration prior to executing synthesis of analogs may be a simple, yet rapid and effective strategy that can be used in conjunction with traditional SAR approaches to aid in the design of potent Gram-negative antibacterials.

2-Methoxypropan-1-ol. Documentation of proposed values of occupational exposure limits (OELs)

2-Methoxypropan-1-ol is a by-product of a propylene glycol methyl ether (PGME) manufacturing process, in which it is an impurity at concentrations up to 5%. 2-Methoxypropan-1-ol as a PGME impurity can occur in industry in paints solvents, varnishes, dyes, inks, adhesion agents, ingredients in cleaning formulations and chemical synthesis intermediates. It may also occur as an impurity in cosmetics, although its use in these products is prohibited. At occupational exposure, 2-methoxypropan-1-ol may be absorbed through inhalation and skin. There are no data on the number of people exposed to this compound in Poland and no data on its toxic effects in humans. There is only one study that showed a statistically significant increase in the occurrence of birth defects in children of mothers exposed to 2-methoxypropan-1-ol. The proposed MAC value for 2-methoxypropan-1-ol (20 mg/m3) is based on the systemic toxicity demonstrated in a study on pregnant rabbits (NOAEC value of 1335 mg/m3). Due to its irritant effects, STEL value of 40 mg/m3 and “I” notation are also proposed. There is no basis for establishing a BEI value. Since dermal exposure may contribute significantly to the absorption of 2-methoxypropan-1-ol by workers, a "skin" notation is also required.

New shielding ZnO-PbO-TeO2 glasses

The effect of PbO and TeO2 concentration on the photon, fast neutron and charged particles shielding capacity of the ternary ZnO-PbO-TeO2 glass systems with the form [(TeO2)0.7-(PbO)0.3]1−x(ZnO)x: x = 0.15–0.25 mol% (TPZ1-TPZ5) glass system was investigated. For this purpose, the mass attenuation coefficient (MAC=μρ) values of the glasses were produced with MCNPX codes and WinXCOM program in the wide energy range of 0.015–15 MeV. Due to the high PbO and TeO2 contributions, the largest MAC values were obtained for the TPZ5 glass. Then important gamma parameters such as effective atomic number, half value layer, effective electron density, equivalent atomic number, and exposure and energy absorption buildup factors (Zeff, HVL, Nel, Zeq and EBF and EABF) were also calculated for TPZ glasses. While the highest Zeff values were found for TPZ5 glass, changing between 48.43 and 51.01, the lowest HVL, EABF and EBF values were calculated for TPZ5 glass. As can be seen from the removal cross section, mass stopping power, and projected range (ΣR, MSP, and PR) results for TPZ glasses, the TPZ5 glass can also be a good shielding material for fast neutrons and alpha-proton particles. As a result, the hypothesis of the study has been confirmed and we believe that the obtained data from this study will be beneficial for the potential use of Te-based glasses in shielding applications.

Attenuation characteristics of high-energy radiation on As-Se-Sn chalcogenide glassy alloy

The present work is mainly interested in the use of chalcogenide glass materials as shielding materials for the highly energetic radiations as X-rays and Gamma rays and particles of high energies as neutrons. The chalcogenide glass system concerned with this study is As40-Se60-x-Snx (x = 0, 5, 10, 15, 20 at %). Numerous radiation shielding factors have been deduced by the aid of Phy-X/PSD online software. This software enabled us to achieve the linear and mass attenuation coefficients (LAC, MAC), effective atomic number Zeff, effective electron density, Neff, half-value layer, HVL, tenth value layer TVL, mean free path MEF, energy absorption and exposure buildup factors (EABF, EBF) in photon energy range extended from 0.15 to 15 MeV. The most interesting findings are that the LAC and MAC values are more suitable for shielding purposes than that of some commercial and traditional glasses. Also the results refer to that HVL, TVL, and MFP decrease with the substitution of Selenium by Tin in the tested system, this decreasing is clearer at the medium and high range of photon energies, which indicate to the improvement of shielding features by the adding of Sn to these specimens. Zeff and Neff of these glasses were in the range (33.6- 40.6) and (2.5-2.86 x 1023 electrons/g) respectively. The results also point to that EBF and EABF decrease with further raising of Snpercentage in the investigated chalcogenide system at all the values of MFP at the hole range of the photon energy, that confirm with no doubt that the samples with higher ratios of Tin have better shielding ability than those of lower ratios of Tin in the investigated system. It is also found that FNRCS of the five investigated specimens is in between 0.0886 Cm-1 and 0.0943 Cm-1 that makes them promising protective materials against neutrons, when compared with other commercial and traditional glasses.

Circular models of air distribution due to piston effect in subways

Subways as places of stay of many people are imposed with higher standards of microclimate at platforms and in tunnels, including the dust criterion. To reduce dust concentrations in tunnel air to MAC values, the authors suggest installation of filters at ventilation connections nearby platforms. Aimed to find operational parameters of the filtering facilities, the authors determine the air velocities at ventilation connections. An original approach is proposed to the air distribution analysis using circular models as they considerably diminish the subway test area size without the loss of the computational accuracy and reduce the computation time.

Extraction of methylene blue coloring agent from model solutions with a plant-origin sorbent

The production output of dyes and pigments in chemical industry is constantly increasing. Sewage waters, which contain synthetic and organic coloring agents, produce toxic effect, which is preconditioned by their low MAC values - below 0.001 mg/dm 2. The most promising method of the pigmented wastewater treatment, which allows reducing the pollutants’ content to the regulated permissible amount, is the adsorption method. This work presents research findings concerning sorption purification of test water media, containing methylene blue coloring agent, by using crop farming waste - chopped sunflower (Heliánthus ánnuus) stalks - as a sorption material. It has been determined that the maximum sorption capacity of chopped sunflower stalks biomass for this coloring agent is 0.245 mmol/dm 2. The processing of the received data has demonstrated that the obtained adsorption isotherm of methylene blue belongs to Type V isotherms according to classification by Brunauer-Deming-Deming-Teller (BDDT) or to the S-type, according to Giles’ classification. This adsorption process is the most accurately described by the Brunauer-Emmett-Teller model (BET), based on the concept of multilayer adsorption.

Synthesis, physical properties, and gamma–ray shielding capacity of different Ni-based super alloys

In this work, five Ni-based alloys with different Cr, Fe, Cu, W, and Re metals mixtures have been prepared and coded as S0, S3, S4, S6, and S9. The crystal structure of the synthesized alloys was analyzed via X-ray Diffraction. The ability of using the prepared alloys for gamma-ray shielding applications has been evaluated via MCNP-5 Monte Carlo simulation code and Xcom theoretical program. All effective shielding factors; mass and linear attenuation coefficient, half-value thickness, and mean free path have been calculated. Mass attenuation coefficient values were ranged from 77.03 to 68.7 cm2/g for S9 and S0 alloys at 0.015 and 15 MeV, respectively. MAC values of the alloys follow the trend that (MAC)S9 > (MAC)S6 > (MAC)S4> (MAC)S3> (MAC)S0 . Additionally, effective atomic number, exposure and energy absorption buildup factors have also been investigated. It is found that the sample posses high values of W + Re ratios possess highest effective atomic number. Furthermore the buildup factors have been changed according to the change in equivalent atomic number. The prepared alloys can be considered useful candidates in radiation shielding applications to reduce workers' exposure in the nuclear reactor area and medical centers.

Characterization of optical and radiation shielding behaviors of ferric oxide reinforced bismuth borate glass

This study aimed to investigate the ferric oxide effect on optical and radiation shielding behaviors of bismuth borate glasses. Gamma-ray attenuation competencies of six glass samples along with optical properties were investigated in terms of their utilization suitability as a shield or personal protection equipment in industrial and medical fields. The chemical composition (60-x) B2O3 + 20Bi2O3 + 20Li2O+xFe2O3 with different Fe2O3 concentrations were prepared using the melt-quenching technique. Gamma-ray attenuation competencies of six glass samples along with optical properties were investigated in terms of their utilization suitability in industrial and medical fields. The outcomes of optical investigations indicated that direct optical band gap (Eg direct) decrease from 5.11 eV to 4.82 eV, while for indirect transition (Eg indirect) decrease from 4.62 eV to 3.79 eV, with increasing Fe2O3 concentrations. To determine the radiation shielding performance, mass attenuation coefficients (μ m) of samples were calculated using FLUKA code and XCOM program between 0.015–15 MeV photon energy range. Accordingly, gamma shielding parameters such as mass (MAC) and linear (LAC) attenuation coefficients, half-value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic numbers (Zeff), electron density (Nel), and fast neutron removal cross sections (ΣR) were evaluated for all glass samples. The results showed that increasing Fe2O3 concentration in glass structure increased the MAC and Zeff. The Fe-10 was reported with the lowest HVL values in addition to the highest MAC and Zeff values.

An investigation into gamma radiation shielding parameters of the (Al:Si) and (Al+Na):Si-doped international simple glasses (ISG) used in nuclear waste management, deploying Phy-X/PSD and SRIM software

Nuclear power plants that produce sustainable energy are the most striking examples of generating carbon-free energy. However, nuclear power plants demand the safe management of nuclear waste. The radiation tests of the materials, which are used in successful waste management in nuclear power plants, must be carried out. In this study, the radiation interaction parameters were examined of International simple glasses (ISG) with superior properties, used in nuclear waste management. The gamma radiation shielding properties of the (Al:Si) and (Al + Na):Si-dopped ISG glasses were investigated using Photon Shielding and Dosimetry (Phy-X / PSD) software for the selected energy range. LAC, MAC, MFP, HVL, TVL, Zeff, Neff, Ceff Zeq, EBF, EABF and FNRCS calculations were applied to assess the radiation protection parameters by Phy-X/PSD software. In addition, MSP and PR (H1, He+2) values were calculated by SRIM software. Also, each obtained parameter provided us with so important information on radiation protection, and these methods have been used frequently in the literature. Substituting an atomic fraction of (Al:Si) with (Al + Na):Si resulted in a reduction of the total atomic cross-section of the glass, which lowered the MAC. The obtained results showed that the highest MAC value belong to ISG-A00N glass. The MAC value gradually decreased as the Al, Na and Si contents increased. Likewise, the HVL, TVL and MFP values changed coherent with this. Moreover, Zeff and Neff values were seen in the ISG-A00N sample to take the maximum values to each other inversely. The most effective glass sample turned out to be ISG-A00N glass at the mean free path penetration power of MSP and PR values. Computations were made for glasses with SiO2, Al2O3, B2O3, Na2O, CaO and ZrO2 content given with ISG-C, ISG-A00, ISG-A12, ISG-A22, ISG-A00N, ISG-A11N, ISG-A18N and ISG-A23N codes. When all the results were evaluated, ISG-A00N glass which has the highest Si and Ca contents and density was found to be the glass with the best radiation shielding feature. It is also noteworthy that this glass does not contain any Al component. As the results of the investigation, it was found out that such a small doped of the Si increases the radiation shielding feature of the glass. The obtained results have revealed that the ISG-A00N > ISG-A00 > ISG-C > ISG-A12 > ISG-A11N > ISG-A22 > ISG-A18N > ISG-A23N samples, in ascending order that attenuators for low energy radiations.

Handgrip Strength and Vitamin D as Predictors of Liver Fibrosis and Malnutrition in Chronic Hepatitis C Patients.

Background In patients with chronic hepatitis C (CHC), a negative impact of associated malnutrition on both morbidity and mortality was reported. We aimed to elucidate the efficacy of serum liver fibrosis markers (fibronectin (FN), hydroxyproline (Hyp), and hyaluronic acid (HA)) and their respective indices (HA index, Hyp index, and FN index) and vitamin D status in predicting malnutrition associated with liver fibrosis in CHC patients and to investigate their association with the value of current clinical malnutrition assessment tools subjective global assessment (SGA), handgrip strength (HGS), and muscle mass scores (SGA, BMI, MAMC, and HGS). Materials and Methods A cross-sectional study was conducted on 80 patients aged 40-60 years with proven viremia, HCV antibodies, HCV-RNA positivity, genotype determinations, and established chronic hepatitis C virus for more than 6 years and 80 control subjects. SGA, HGS, and muscle mass score (MAMC) were estimated in both patients and control subjects. Based on SGA scores, CHC patients were classified into three groups: well nourished (n = 12; SGA-A); mild or moderately malnourished (n = 25; SGA-B); and severely malnourished (n = 43; SGA-C). Liver fibrosis markers, inflammatory indicator α-Fetoprotein (AFP), tumor necrosis factor-alpha (TNF-α), 25-hydroxyvitamin D, and PTH were estimated using immunoassay techniques. Results CHC patients with moderate and severe malnutrition SGA scores showed a significant decline in the levels of vitamin D, increased PTH, and lower values of HGS and muscle mass indices compared to well-nourished patients and control subjects. In addition, malnutrition, vitamin D deficiency, and lower values of HGS, MAC, TSF, and MAMC showed significant correlation with liver severity among CHC patients. Liver fibrosis markers Hyp, HA, FN, APRI, HypI, HAI, and FNI as noninvasive biomarkers showed significant correlation with both severity of liver diseases and associated malnutrition, especially in cirrhotic HCV patients (F4) compared to those with significant fibrosis (F2–F3). Conclusion The results showed that deficiency in vitamin D levels, HGS, SGA, and muscle mass scores (MAC, MAMC, or TSF) could be used as markers of liver pathogenicity in patients with CHC. In addition, the study concluded that noninvasive biomarkers Hyp, HA, FN, APRI, HypI, HAI, and FNI separately or in association with vitamin D status, HGS, SGA, and muscle mass scores (MAC, MAMC, or TSF) were significantly associated with an incidence of malnutrition between ~70.5% and 89.6% of CHC patients with significant fibrosis and cirrhosis.