Range Of Iodine Concentrations Research Articles

4D Dynamic contrast-enhanced breast CT: Phantom-based reconstruction parameter optimization for iodine quantification.

Four-dimensional dynamic contrast-enhanced breast CT (4D DCE-bCT) offers promising high-resolution spatial and temporal imaging capabilities for the characterization and monitoring of breast tumors. However, the optimal combination of parameters for iodine quantification in image space remains to bedetermined. This study aims to optimize a dedicated bCT system to perform long dynamic contrast-enhanced scans with high spatio-temporal resolution while maintaining a reasonable radiation dose. Our protocol includes the acquisition of a high-quality prior image that is reconstructed with a polychromatic iterative algorithm (IMPACT). The acquisition of the post-contrast sequence is continuous but sparse and these images are reconstructed using prior image constrained compressed sensing (PICCS). A four-step optimization process is performed using images of a physical phantom. First, the optimal tube current is selected by taking the noise level into account. Second, the optimal number of angles is selected based on the absence of streak artifacts. Third, the number of iterations in IMPACT is specified at the lowest value that achieves the highest spatial resolution. Finally, the number of iterations in PICCS is determined based on the quantitative accuracy of a range of iodine concentrations. When a high-quality prior image is available, the imaging of post-contrast images can be performed using just 40 projection angles with a tube current of 32 mA. The noise level in the post-contrast images is inherited from the prior image and no streak artifacts are visible. Mean difference between the linear attenuation coefficients of samples containing iodine reconstructed with IMPACT using all 360 projections and PICCS using 40 projections is 0.0004 at most. The spatial resolution of images reconstructed with PICCS is lower than the one of IMPACT images and is concentration dependent. The cut-off frequency at 10% modulation transfer function drops from 1.55 in the prior image to 0.9 when the target with the largest concentration is evaluated. The total mean glandular dose of the protocol does not exceed 22.5mGy. This study found the optimal acquisition and reconstruction parameters for a low-dose dynamic contrast-enhanced bCT protocol. The numerical accuracy of the proposed protocol was ensured by performing a physical phantomstudy.

Impact of patient habitus and acquisition protocol on iodine quantification in dual-source photon-counting computed tomography.

Evaluation of iodine quantification accuracy with varying iterative reconstruction level, patient habitus, and acquisition mode on a first-generation dual-source photon-counting computed tomography (PCCT) system. A multi-energy CT phantom with and without its extension ring equipped with various iodine inserts (0.2 to 15.0mg/ml) was scanned over a range of radiation dose levels ( 0.5 to 15.0mGy) using two tube voltages (120, 140kVp) and two different source modes (single-, dual-source). To assess the agreement between nominal and measured iodine concentrations, iodine density maps at different iterative reconstruction levels were utilized to calculate root mean square error (RMSE) and generate Bland-Altman plots by grouping radiation dose levels (ultra-low: ; low: 1.5 to 5; medium: 5 to 15mGy) and iodine concentrations (low: ; high: 5 to 15mg/mL). Overall, quantification of iodine concentrations was accurate and reliable even at ultra-low radiation dose levels. RMSE ranged from 0.25 to 0.37, 0.20 to 0.38, and 0.25 to 0.37mg/ml for ultra-low, low, and medium radiation dose levels, respectively. Similarly, RMSE was stable at 0.31, 0.28, 0.33, and 0.30mg/ml for tube voltage and source mode combinations. Ultimately, the accuracy of iodine quantification was higher for the phantom without an extension ring (RMSE 0.21mg/mL) and did not vary across different levels of iterative reconstruction. The first-generation PCCT allows for accurate iodine quantification over a wide range of iodine concentrations and radiation dose levels. Stable accuracy across iterative reconstruction levels may allow further radiation exposure reductions without affecting quantitative results.

The Assessment of Iodine Concentrations in Colostrum and Breast Milk Using ICP-MS: The Impact of Delivery Type, Thyroid Function and Gestational Diabetes-A Pilot Study.

Considering the spectrum of benefits of breast milk feeding, determining the essential components of an infant's only food-mother's milk-seems justified, especially in the case of those whose deficiency (e.g., iodine) may result in developmental disorders. The main aim of this study was the determination of the total iodine content of breast milk (including colostrum and mature milk). A secondary objective was to assess the influence of factors such as the type of delivery, hypothyroidism, gestational diabetes or the stage of lactation on this parameter. The study materials were colostrum and milk after 1 (n = 14), 2 and 3 months (n = 8) of lactation with a range of iodine concentrations (µg/L): 195-1648 and 170-842, 174-650 and 273-751, respectively. Iodine was determined using the inductively coupled plasma mass spectrometry (ICP-MS). Multivariate statistical analysis revealed, e.g., that delivery by caesarean section or dose of L-thyroxine taken by women to normalise thyroid hormones, had a significant effect on iodine concentrations in breast milk. Further research aimed at assessing the quality of breast milk should also include determining the factors influencing it.

Analytical validation of an inductively coupled plasma mass spectrometry method for urinary iodine concentration measurements in Taiwan

Urinary iodine concentration (UIC) measured by Sandell-Kolthoff spectrophotometric method has been used in the Nutrition and Health Surveys in Taiwan but this method is time consuming and produces toxic waste from arsenic trioxide. The aim of this study was to develop and validate an inductively coupled plasma mass spectrometry (ICP-MS) system to determine UIC in Taiwan. Samples and iodine calibrators were diluted 100-fold into an aqueous solution containing Triton X-100, 0.5% ammonia solution, and tellurium (128Te) as an internal standard. Digestion prior to analysis was not necessary. Precision, accuracy, serial dilution, and recovery tests were performed. A total of 1243 urine samples covering a wide range of iodine concentrations were measured by both Sandell-Kolthoff method and ICP-MS. Passing-Bablok regression and Bland-Altman plots were used to compare values across methods. The limit for detection and quantification by ICP-MS was 0.95μg/L and 2.85μg/L, respectively. The intra-assay and inter-assay coefficients were <10%, with a recovery range of 95%-105%. The results obtained by ICP-MS and the Sandell-Kolthoff method were highly correlated (Pearson's correlation: r=0.996, 95% confidence interval [CI]: 0.9950-0.9961, p<0.001). For UIC between 20 and 1000μg/L, the y-intercept for the Passing-Bablok regression was -1.9 (95% CI: -2.5599 to -1.3500) and the slope was 1.01 (95% CI: 1.0000-1.0206). This validated ICP-MS system can be used for measuring UIC.

Determination of total iodine content in edible seaweeds: Application of inductively coupled plasma-atomic emission spectroscopy

Iodine is an essential element necessary for the synthesis of thyroid hormones, and its deficiency is a common problem worldwide. To avoid iodine insufficiency, the intake of this element must be properly evaluated concerning its adequate intake (AI), which is estimated at 90, 150, and 200 μg per day, for children, adults, and pregnant women, respectively. One of the most abundant resources available for iodine is the consumption of edible seaweeds. In this work, ten species of edible seaweeds: one green (Ulva rigida), five red (Chondracanthus teedei var. lusitanicus, Chondrus crispus, Gracilaria gracilis, Grateloupia turuturu, Osmundea pinnatifida), and four brown species (Bifurcaria bifurcata, Fucus vesiculosus, Saccorhiza polyschides, Undaria pinnatifida), collected from the near-pristine Portuguese seashore, were analyzed for iodine content. The iodine concentration was determined by optimized microwave-assisted extraction in aqua regia (AR), followed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis. The method was validated by using the standard reference material (kelp) obtaining a maximum recovery of 100 ± 15%. The studied species contained a wide range of iodine concentrations, ranging from 33 ± 3 μg g−1 dry weight (dw) (U. rigida), up to 302 ± 26 μg g−1 dw (O. pinnatifida), 352 ± 21 μg g−1 dw (F. vesiculosus) and 391 ± 24 μg g−1 dw (B. bifurcata). The results show that the analyzed seaweeds can serve as a beneficial resource for iodine, however, their consumption must be balanced in a way that does not exceed the adequate estimated iodine intake for population groups.

Quality Assessment of some Povidone-Iodine Pharmaceutical Preparations

The aim of the present work was to determine the active pharmaceutical ingredient of samples of povidoneiodine solutions 10% (topical solution and vaginal douche), which were obtained from market in Syria (A, B, C) for povidone-iodine 10% topical solution and (D, E, F) for povidone-iodine 10% vaginal douche and one solution produced by Mundipharma Company (Betadine 10% topical solution and Betadine 10% vaginal douche), which used as a reference. The research included control of solutions pH and free iodine concentration. In addition, the factors affecting stability of previous solutions and control stability of samples during the date of validity were studied. The results obtained showed that only 50% of the samples evaluated were within the iodine concentration range required. For povidone-iodine 10% topical solution, sample (A) was the closest to Betadine 10% topical solution, which had the highest level. Study revealed significant difference between local companies, where (A) had the best bactericidal effect. In addition, stability study of samples revealed that 50% of samples showed a significant decrease in iodine content in the second year of validity. For povidone-iodine 10% vaginal douche, the sample (E) was the closest to Betadine 10% vaginal douche, which had the highest level. Study revealed significant difference between local companies, where (E) had the best bactericidal effect. In addition, stability study of samples revealed that 50% of samples showed a significant decrease in iodine content in the second year of validity. The pH values of the local samples solutions were within the range (1.56.5) of activity and stability.

Accuracy of the raw-data-based effective atomic numbers and monochromatic CT numbers for contrast medium with a dual-energy CT technique.

To evaluate the accuracy of raw-data-based effective atomic number (Zeff) values and monochromatic CT numbers for contrast material of varying iodine concentrations, obtained using dual-energy CT. We used a tissue characterization phantom and varying concentrations of iodinated contrast medium. A comparison between the theoretical values of Zeff and that provided by the manufacturer was performed. The measured and theoretical monochromatic CT numbers at 40-130 keV were compared. The average difference between the Zeff values of lung (inhale) inserts in the tissue characterization phantom was 81.3% and the average Zeff difference was within 8.4%. The average difference between the Zeff values of the varying concentrations of iodinated contrast medium was within 11.2%. For the varying concentrations of iodinated contrast medium, the differences between the measured and theoretical monochromatic CT values increased with decreasing monochromatic energy. The Zeff and monochromatic CT numbers in the tissue characterization phantom were reasonably accurate. The accuracy of the raw-data-based Zeff values was higher than that of image-based Zeff values in the tissue-equivalent phantom. The accuracy of Zeff values in the contrast medium was in good agreement within the maximum SD found in the iodine concentration range of clinical dynamic CT imaging. Moreover, the optimum monochromatic energy for human tissue and iodinated contrast medium was found to be 70 keV. Advances in knowledge: The accuracy of the Zeff values and monochromatic CT numbers of the contrast medium created by raw-data-based, dual-energy CT could be sufficient in clinical conditions.

Performance characteristics of the Inveon micro-CT scanner in small animal imaging

InveonTM is a tri-modality (Siemens Medical Solutions) imaging system designed to image rodents such as mice and rats. The objective of this study was to characterize the performance of the CT component of the scanner in terms of image noise, uniformity, spatial resolution as well as image quality. A clinically relevant water phantom was used for the measurement of image noise and uniformity. Spatial resolution was measured by calculating the modulation transfer function (MTF) using the slanted edge method. Image noise was estimated under several conditions of beam amperage (50–500 μA) and x-ray CT voltages (40–80 kVp) at an exposure time of 200 ms. The CT number for different tissues was measured using a manufacturer-supplied phantom of different densities (0, 50, 250, 750 mg/cc). System linearity was assessed using a wide range of iodine concentrations (Ultravist 370) ranging from 5 to 70 mg/cc. No significant change was noticed for image uniformity across the whole range of tube currents at voltage of 80 kVp. However, a significant reduction of the noise was noticed when the current increased from 50 to 500 μA and also with gradual increment of the tube voltage. The best noise measure was obtained at 500 μA and 80 kVp. Noise or ring reduction feature showed a significant reduction of the noise level. The relationship between noise and the current was shown to be dominated by the photon statistics with less contribution from the system noise. The MTF measurements showed a resolution of 198 μm, 43 μm and 9.52 μm respectively at 10% modulation. A good linear correlation was found between the CT number and iodine concentrations with high statistical significance. The system has shown good CT performance measures in terms of uniformity, spatial resolution, image noise and contrast linearity. Clinical results showed the capability of the system in acquiring high spatial resolution images. One of the shortcomings is disability to perform 4D CT and thus additional engineering work is requested to further enhance the sensitivity and temporal resolution of the scanner.

Properties of iodine containing diamond-like carbon films prepared by plasma source ion implantation

The addition of halogens to diamond-like carbon (DLC) films provides attractive film properties, e.g. a hydrophobic surface combined with an improved corrosion protection. The use of iodine is of interest in this regard because of its additional marked influence on the band gap and therefore on the optical properties of the film. Instead of solid iodine, the gaseous precursor trifluoroiodomethane (CF3I) was used to prepare iodine containing DLC films. In contrast to our earlier experiments, a lower voltage was used in the plasma based preparation process thereby extending the iodine concentration range. The film properties, such as halogen content, bonding, water contact angle and corrosion protection were evaluated. The iodine containing DLC films are suitable to be deposited on polymer materials.

Preparation of monoclinic Cu2SnS3 single crystal by chemical vapor transport with iodine

Single crystals of monoclinic Cu2SnS3 (CTS) were prepared by chemical vapor transport using iodine as a transport agent. A range of iodine concentrations from 1.5 to 3.0mg/cm3 was employed to determine its effect on crystal growth. The crystals were quenched after vapor transport to prevent the growth of additional, secondary CTS phases. A stoichiometrically balanced CTS product (with a composition ratio of Cu:Sn:S=2.05:1.01:2.94) was achieved using an iodine concentration of 2.0mg/cm3. The results of Raman scattering and X-ray diffraction analyses showed that the samples were CTS crystals with a monoclinic structure. The sample was confirmed to be a single crystal by selected-area electron diffraction patterns, which showed a regular array of spots consistent with monoclinic CTS.

The value of using iodine maps in distinguishing the benign and malignant thyroid nodule with dual-source CT by dual energy

Objective To investigate the clinical application of iodine-enhanced image of dual-source computed tomography(DSCT)in distinguishing benign and malignant thyroid nodules. Methods Thirty patients with thyroid nodules underwent DSCT imaging with dual-source computed tomography. All thyroid nodules were confirmed by operation or biopsy. Iodine concentration in the thyroid nodule and normal thyroid tissue were calculated and not enhanced. A receiver operator characteristic curve in SPSS software was utilized to select critical value of optimum sensitivity and specificity. The data were retrospectively analyzed. Results There were 30 patients with 40 thyroid nodules(17 malignant nodules, 23 benign nodules). The range of iodine concentration in malignant nodules was -2.4-0.9 mg/ml(median -0.5 mg/ml), and that in normal thyroid tissue was -0.9-2.2 mg/ml(median 0.7 mg/ml). The range of iodine concentration in benign nodules was 1.5-4.4 mg/ml(median 2.4 mg/ml), and that in normal thyroid tissue was 1.5-4.3 mg/ml(median 2.6 mg/ml). Among them, the iodine concentration in the solid part of benign nodules was significantly higher than that in malignant nodules, the difference was statistically significant(Z=-3.23, P=0.21). When critical value was 0.15 mg/ml, sensitivity was 82.40%, specificity was 81.00%. Conclusion Iodine-enhanced images with DSCT in non-enhanced weighted images may be an implement tool for differential diagnosis of benign and malignant nodules of the thyroid gland. (Chin J Endocrinol Metab, 2015, 31: 333-336) Key words: Thyroid nodule; Tomography, X-ray computed; Iodine image

Accuracy of dual-energy computed tomography for the measurement of iodine concentration using cardiac CT protocols: validation in a phantom model

To assess the accuracy of dual-energy CT (DECT) for the quantification of iodine concentrations in a thoracic phantom across various cardiac DECT protocols and simulated patient sizes. Experiments were performed on first- and second-generation dual-source CT (DSCT) systems in DECT mode using various cardiac DECT protocols. An anthropomorphic thoracic phantom was equipped with tubular inserts containing known iodine concentrations (0-20 mg/mL) in the cardiac chamber and up to two fat-equivalent rings to simulate different patient sizes. DECT-derived iodine concentrations were measured using dedicated software and compared to true concentrations. General linear regression models were used to identify predictors of measurement accuracy Correlation between measured and true iodine concentrations (n = 72) across CT systems and protocols was excellent (R = 0.994-0.997, P < 0.0001). Mean measurement errors were 3.0 ± 7.0% and -2.9 ± 3.8% for first- and second-generation DSCT, respectively. This error increased with simulated patient size. The second-generation DSCT showed the most stable measurements across a wide range of iodine concentrations and simulated patient sizes. Overall, DECT provides accurate measurements of iodine concentrations across cardiac CT protocols, strengthening the case for DECT-derived blood volume estimates as a surrogate of myocardial blood supply. • Dual-energy CT provides new opportunities for quantitative assessment in cardiac imaging. • DECT can quantify myocardial iodine as a surrogate for myocardial perfusion. • DECT measurements of iodine concentrations are overall very accurate. • The accuracy of such measurements decreases as patient size increases.

Eliminated risk of iodine contrast cancellation with multibin spectral CT

This note compares the extent of contrast cancellation induced by iodinated contrast agents in energy integrating and photon counting multibin CT images. The contrast between a hypodense target and soft tissue is modeled for the two systems for a range of iodine concentrations and tube voltages. In energy integrating systems, we show that the contrast vanishes for low concentrations of iodine whereas the same effect is not seen in multibin systems. We conclude that it is the ability of multibin systems to apply weighting schemes post-acquisition that allows the operator to eliminate the risk of contrast cancellation between iodinated targets and the background.

Nuclear Magnetic Resonance Studies of Reorientational Motion and Li Diffusion in LiBH4–LiI Solid Solutions

To study the reorientational motion of the BH4 groups and the translational diffusion of Li+ ions in LiBH4–LiI solid solutions with 2:1, 1:1, and 1:2 molar ratios, we have measured the 1H, 11B, and 7Li NMR spectra and spin–lattice relaxation rates in these compounds over the temperature range 18–520 K. It is found that, at low temperatures, the reorientational motion of the BH4 groups in LiBH4–LiI solid solutions is considerably faster than in all other borohydride-based systems studied so far. Our results are consistent with a coexistence of at least two types of reorientational processes with different characteristic rates. For the faster reorientational process, the average activation energies derived from our data are 53 ± 4, 39 ± 4, and 33 ± 4 meV for the LiBH4–LiI solid solutions with 2:1, 1:1, and 1:2 molar ratios, respectively. In the studied range of iodine concentrations, the Li+ jump rates are found to decrease with increasing I– content. The activation energies for Li diffusion obtained from o...

Use of Iodized Versus Non-iodized Sodium Chloride in Therapeutic Dips and Baths for Freshwater Fish

Salt (NaCl) is a common therapeutant in fish culture. The use of salt containing iodine may be harmful to fish. The goal of this study was to determine if using iodized saltfor dips and baths increases morbidity/mortality of fish and establishes the LC50 of iodine for three commercially important species: koi, Cyprinus carpi; guppy, Poecilia reticulata; and Jack Dempsey, Rocio octofasciata. Fish were exposedto a salt bath (4 g/L) or a salt dip (25 g/L) using either iodized or non-iodized salt and observed for clinical signs of iodine toxicity or death. For the LC50 trials, one fish of each species was exposed to a range of iodine concentrations for a period of 24 h. There were no significant differences in mortality between fish treated with iodized vs. non-iodized salt. The use of iodized salt for baths and dips appears to be safe in the three species tested. LC50 of iodine in these species appears to be greater than 1.4 mg/L.

A solid iodinated phantom material for use in tomographic x‐ray imaging

Iodinated phantoms are of value in x-ray imaging for quality control measurements, system calibration, and for use in the research setting; however, the liquid phantoms that are most often used have several limitations including variability between repeated dilutions, inhomogeneities from air bubbles or precipitants, and long set up times. Although suitable materials have been investigated for projection radiography, quantitative measurements of contrast enhancement in computed tomography (CT) have become increasingly important in the clinic, and a need exists for a durable and reproducible iodinated phantom material. In this work, the authors describe a solid radiographic phantom material that has an accurately known concentration of iodine distributed uniformly throughout its volume and that has stable properties over time. This material can be molded or machined into a desired shape to create a test object or for use in an anthropomorphic phantom. Two sets of calibration phantoms were produced with a clinically relevant range of iodine concentrations. Measurements were made on these phantoms to characterize the material properties in terms of accuracy of iodine concentration, radiographic uniformity, temporal stability of x-ray attenuation, and manufacturing repeatability. Experimentally measured linear x-ray attenuation coefficients were compared to those predicted by a theoretical model. The uniformity of the iodine distribution in the material was assessed by measuring image intensity variation, both in projection images and in reconstructed CT volumes. The reproducibility of manufacture was estimated on a set of independently produced samples. A longitudinal study was performed to assess the stability of the material x-ray characteristics over time by making measurements at 6 month intervals. Good agreement was seen between the experimental measurements of effective attenuation and the theoretically predicted values. It is estimated that a desired iodine concentration could be produced to within 0.04 mg/ml. Comparison of the measured effective linear iodine attenuation coefficients of eight 1.0 mg/ml samples indicated a manufacturing reproducibility of +/-0.03 mg/ml iodine. Variations in uniformity across each of the samples were on the order of image intensity fluctuations (sigma). No inhomogeneities due to mixing or settling were apparent. An analysis of longitudinal data collected for both calibration sets revealed no perceptible change in radiographic properties over the first 6 months after manufacture, nor over a subsequent 1.5 yr period from 1 yr postmanufacture onward. The uniformity, stability, and precision of this iodinated material suggest that it is suitable for use in accurate calibration tools for contrast tomographic imaging.

Experimental vapour–liquid equilibrium data of HI–H 2O–I 2 mixtures for hydrogen production by Sulphur–Iodine thermochemical cycle

The Sulphur–Iodine thermochemical cycle for hydrogen production has been investigated by ENEA in the framework of the Italian TEPSI Project whose main objective is the realization of an integrated loop plant at a laboratory scale. For the design of the separation–purification equipments, the study of vapour–liquid equilibrium characterization of the ternary HI–H 2O–I 2 system is considered a key factor. The aim of the present work is to provide new experimental isobaric vapour–liquid equilibrium data for this system by ebulliometry varying both temperature and solution composition. The temperature range has been extended up to about 144 °C, the iodine concentration range from 0.2%w/w to 90%w/w while HI weight fraction varies from 4%w/w to 67%w/w in the liquid phase. Most of the data obtained in this work are in good agreement with other experimental data retrieved from literature, which have been recorded in similar operative conditions but acquired by different procedures.

A simple method to estimate the optimum iodine concentration of contrast material through microcatheters: hydrodynamic calculation with spreadsheet software

It is important to increase the iodine delivery rate (I), that is the iodine concentration of the contrast material (C) × the flow rate of the contrast material (Q), through microcatheters to obtain arteriograms of the highest contrast. It is known that C is an important factor that influences I. The purpose of this study is to establish a method of hydrodynamic calculation of the optimum iodine concentration (i.e., the iodine concentration at which I becomes maximum) of the contrast material and its flow rate through commercially available microcatheters. Iopamidol, ioversol and iohexol of ten iodine concentrations were used. Iodine delivery rates (I meas) of each contrast material through ten microcatheters were measured. The calculated iodine delivery rate (I cal) and calculated optimum iodine concentration (calculated C opt) were obtained with spreadsheet software. The agreement between I cal and I meas was studied by correlation and logarithmic Bland-Altman analyses. The value of the calculated C opt was within the optimum range of iodine concentrations (i.e. the range of iodine concentrations at which I meas becomes 90% or more of the maximum) in all cases. A good correlation between I cal and I meas (I cal = 1.08 I meas, r = 0.99) was observed. Logarithmic Bland–Altman analysis showed that the 95% confidence interval of I cal/I meas was between 0.82 and 1.29. In conclusion, hydrodynamic calculation with spreadsheet software is an accurate, generally applicable and cost-saving method to estimate the value of the optimum iodine concentration and its flow rate through microcatheters.

Iodine concentrations in cow's milk in Central and Northern Bohemia

Iodine deficiency and related risks of medical and/or developmental disorders in humans are a worldwide problem. In the last years, Czech endocrinologists and paediatricians have observed a significant increase in the occurrence of goitre in children and adolescents caused by a low dietary intake of iodine. Given the low consumption of seafood, milk and dairy products are the main sources of iodine in theCzechRepublic. Iodine contents of milk of dairy cows of different breeds from seven farms located in Central andNorthern Bohemia were studied over a period of 17 months (April 2000 through August 2001). Iodine content was determined by high-performance liquid chromatography with electrochemical detection (HPLC-ECD) based on IDF Standard 167 (1994), following alkaline mineralization of the sample. An analysis of the certified reference material CRM&amp;nbsp;063 was used to examine the accuracy of determination. Two-way analysis of variance (ANOVA) with and without replications, including Scheffe&amp;rsquo;s comparison at a 5% level of significance, was used for statistical evaluation of experimental data. The iodine content of milk ranged from 147 to 605 &amp;micro;g/kg (mean 251  110 &amp;micro;g/kg) during the winter season, and from 35 to 484 &amp;micro;g/kg (mean 212  104 &amp;micro;g/kg) during the summer season. The mean iodine concentration in all samples of milk during the studied period was 225  109 &amp;mu;g/kg.The wide range of iodine concentrations is connected with differences in iodine saturation of dairy cows and it is a result of multiple factors. Iodine reserves in the soil play an important role and influence the content of iodine in feeds for dairy cows and thereby the iodine levels in milk. The presence of goitrogenic substances in feed for dairy cows is another important factor. The iodine content was found to be statistically significantly lower in the milk from dairy cows fed a diet enriched with rapeseed cakes compared to that of dairy cows on a diet without rapeseed cake. Dairy cows on farm F6, which were fed maize silage without added rapeseed cake during winter, had a statistically higher iodine content in milk during the winter season compared to summer, when they were fed fresh fodder. Fresh fodder is supposed to contain goitrogenic substances which significantly reduce iodine levels in milk. This opinion is supported by experimental findings that the date of milk sample collection has no statistically significant influence on milk iodine levels if the dairy cows are fed a diet containing added rapeseed cake (farms F1, F2, F3, and F4) throughout the year. Compared to the other farms, statistically significantly higher milk iodine content was found on farm F5. The mean iodine content in milk from farm F5 was 425  74 &amp;mu;g/kg during the studied period. The main cause is probably that the diet contained no rapeseed cake. &amp;nbsp;

Electronic and Structural Evidences for Charge Transfer and Localization in Iodine-Doped Pentacene

We have investigated the doping mechanism of pentacene with iodine and its impact on the structure and on the electronic properties of single crystals, powders, and thin films in a large range of iodine concentration up to six iodine per pentacene (PEN) molecule (I/PEN = 6). Three regimes of doping have been identified. In the low doping regime I/PEN < 0.05, the pristine pentacene structure of single crystals is maintained. Electron spin resonance (ESR) evidences a Pauli susceptibility, that is, the characteristic fingerprint of delocalized holes in the valence band of pentacene. In the intermediate doping regime (0.1 < I/PEN ≤ 2.0), iodine diffuses between the (a,b) planes of the pentacene structure and forms an intercalate. Charge transfer between iodine and pentacene is witnessed by both UV−vis and IR signatures of PEN+ cations and related species, for example, cation dimers (PEN+)2 and typical Raman signatures of the I3- and I5- species. Spin pairing of pentacene cation radicals is further supported b...