bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic MRI, dynamic multidetector‐row computed tomography (MDCT), and coregistered 2‐[fluorine‐18]‐fluoro‐2‐deoxy‐D‐glucose–positron emission tomography (FDG‐PET)/CT: Comparative study of capability for management of pulmonary nodules
Authors: Ohno Yoshiharu , Koyama Hisanobu , Takenaka Daisuke , Nogami Munenobu , Maniwa Yoshimasa , Nishimura Yoshihiro , Ohbayashi Chiho , Sugimura Kazuro
Published: May 2008

Purpose

To compare the nodule management capabilities of dynamic MRI, dynamic multidetector‐row computed tomography (MDCT) and coregistered positron emission tomography (PET)/CT.

Materials and Methods

Dynamic MRI, dynamic MDCT, PET, microbacterial, and pathological examinations were administered to 175 consecutive patients with 202 nodules (<30 mm in diameter). The final diagnoses resulted in the classification of 202 nodules into two groups: requiring further intervention and treatment (N = 163) and no further evaluation (N = 39) groups. Maximum relative enhancement and slope of enhancement ratio were calculated as dynamic MR indices. Maximum enhancement, net enhancement, slope of enhancement, and absolute loss of enhancement were calculated as dynamic CT indices. maximum value of standard uptake value (SUVmax) was measured on coregistered PET/CT. Receiver operating characteristics (ROC) analyses were performed to determine feasible threshold values for nodule management, and results were tested using McNemar's test.

Results

When feasibility threshold values were adopted for nodule management, the specificity (82.1%) and accuracy (93.6%) of the slope of the enhancement ratio were significantly higher than those of dynamic CT indices (P < 0.05) and SUVmax (P < 0.05).

Conclusion

Dynamic MRI can play a more specific and/or accurate role for nodule management as compared with dynamic MDCT and coregistered PET/CT. J. Magn. Reson. Imaging 2008;27:1284–1295. © 2008 Wiley‐Liss, Inc.
MR factor analysis: Improved technology for the assessment of 2D dynamic structures of benign and malignant salivary gland tumors
Authors: Eida Sato , Ohki Masafumi , Sumi Misa , Yamada Toshiro , Nakamura Takashi
Published: May 2008

Purpose

To establish an MR factor analysis technique for two‐dimensional (2D) MR dynamic structures of benign and malignant salivary gland tumors.

Materials and Methods

Dynamic contrast‐enhanced MRI using a surface coil was performed on 36 patients with benign (N = 24) or malignant (N = 12) salivary gland tumors. Signal intensity kinetics in each pixel of the tumors after contrast medium injections were semiautomatically categorized into four patterns (slow uptake, rapid uptake with high washout, rapid uptake with low washout, and flat). The 2D distributions of the kinetic patterns in the tumors were compared with the histological features of the corresponding parts of the excised tumors and with overall kinetics obtained by a conventional analysis.

Results

The MR factor analysis technique allowed the pixel‐to‐pixel evaluation of the contrast enhancement kinetics of the salivary gland tumors. The 2D distributions of the time‐intensity curve (TIC) patterns correlated well with the histological features of the salivary gland tumors and allowed more detailed dynamic structures of the tumors compared with the results obtained by the conventional dynamic study analysis.

Conclusion

The proposed MR factor analysis would be clinically feasible to diagnose salivary gland tumors and tumor‐like lesions. J. Magn. Reson. Imaging 2008;27:1256–1262. © 2008 Wiley‐Liss, Inc.
Evaluation of optimized inversion‐recovery fat‐suppression techniques for T2‐weighted abdominal MR imaging
Authors: Lauenstein Thomas C. , Sharma Puneet , Hughes Timothy , Heberlein Keith , Tudorascu Dana , Martin Diego R.
Published: May 2008

Purpose

To test the theoretical benefits of a spectral attenuated inversion‐recovery (SPAIR) fat‐suppression (FS) technique in clinical abdominal MRI by comparison to conventional inversion‐recovery (IR) FS combined with T2‐weighted (T2W) partial Fourier single shot fast spin echo (SSFSE).

Materials and Methods

1.5T MRI studies of the abdomen were performed in 28 patients with liver lesions (hemangiomas n = 14; metastases n = 14). T2W sequences were acquired using IR and SPAIR SSFSE. Measurements included retroperitoneal and mesenteric fat signal‐to‐noise (SNR) to evaluate FS; liver lesion contrast‐to‐noise (CNR) to evaluate bulk water signal recovery effects; and bowel wall delineation to evaluate susceptibility and physiological motion effects.

Results

SPAIR‐SSFSE images produce significantly improved FS and liver lesion CNR. The mean SNR of the retroperitoneal and mesenteric fat for SPAIR SSFSE was 20.5 ± 10.2 (±1 SD) and 12.7 ± 6.2, compared to 43.2 ± 24.1 (P = 0.000006) and 29.3 ± 16.8 (P = 0.0000005) for IR‐SSFSE. SPAIR‐SSFSE images produced higher CNR for both hemangiomas CNR = 164 ± 88 vs. 126 ± 83 (P = 0.00005) and metastases CNR = 75 ± 27 vs. 53 ± 19 (P = 0.007). Bowel wall visualization was significantly improved using SPAIR‐SSFSE (P = 0.002).

Conclusion

The theoretical benefits of SPAIR over conventional IR FS translate into significant multiple improvements that can be measured on clinical abdominal MRI scans. J. Magn. Reson. Imaging 2008;27:1448–1454. © 2008 Wiley‐Liss, Inc.
Equivalent cross‐relaxation rate imaging of axillary lymph nodes in breast cancer
Authors: Mastsushima Shigeru , Nishiofuku Hideyuki , Iwata Hiroji , Era Seiichi , Inaba Yoshitaka , Kinosada Yasutomi
Published: May 2008

Purpose

To determine whether equivalent cross‐relaxation rate (ECR) imaging (ECRI) is a feasible method for optimization of axillary lymph node dissection (ALND) and thereby improve quality‐of‐life (QOL).

Materials and Methods

A total of 50 breast cancer patients underwent ECRI, with off‐resonance saturation pulse at frequency offset of 5 ppm. ECR threshold values were determined to evaluate metastases to lymph nodes in the ALND group before examining the relationship between ECR value and cellular density. Metastases to lymph nodes of the sentinel lymph node biopsy (SLNB) group were evaluated based on the results of the ALND group.

Results

In the ALND group, regions without metastases showed a higher cellular density and ECR value than those with metastases. The relationship of ECR value to cellular density formed two clusters according to the presence or absence of metastasis; cellular density was related to ECR value for both clusters. In the SLNB group, supposing a threshold ECR value of 80%, sensitivity and specificity were 88.2% and 100%, respectively.

Conclusion

ECRI is a potentially useful method for cellular density imaging of axillary lymph nodes. ECRI provides active information that enables ALND to be avoided, thus improving QOL. J. Magn. Reson. Imaging 2008;27:1278–1283. © 2008 Wiley‐Liss, Inc.
MRI measurement of change in vascular parameters in the 9L rat cerebral tumor after dexamethasone administration
Authors: Ewing James R. , Brown Stephen L. , Nagaraja Tavarekere N. , Bagher‐Ebadian Hassan , Paudyal Ramesh , Panda Swayamprava , Knight Robert A. , Ding Guangliang , Jiang Quan , Lu Mei , Fenstermacher Joseph D.
Published: May 2008

Purpose

To demonstrate in the rat 9L cerebral tumor model that repeated MRI measurements can quantitate acute changes in the blood‐brain distribution of Gadomer after dexamethasone administration.

Materials and Methods

A total of 16 Fischer 344 rats were studied at 7T, 15 days after cerebral implantation of a 9L tumor. MRI procedures employed a T‐One by Multiple Read Out Pulses (TOMROP) sequence to estimate R1 (R1 = 1/T1) at 145‐second intervals before and after administration of Gadomer (Bayer), a macromolecular contrast agent (CA). Two baseline studies preceded Gadomer administration and 10 subsequent R1 maps tracked CA concentration in blood and brain for 25 minutes. Thereafter, either dexamethasone (N = 10) or normal saline (N = 6) was administered intravenously. A total of 90 minutes later a second series of 12 TOMROP measurements of Gadomer distribution was performed. The influx constant, K1, plasma distribution volume, vD, backflux constant, kb, and interstitial space, ve, were determined, and the test‐retest differences of each of four vascular parameters were calculated.

Results

Dexamethasone decreased K1 approximately 60% (P = 0.02), lowered kb and vD (P = 0.03 and P < 0.01, respectively), and marginally but insignificantly decreased ve.

Conclusion

This noninvasive MRI technique can detect drug effects on blood‐brain transfer constants of CAs within two hours of administration. J. Magn. Reson. Imaging 2008;27:1430–1438. © 2008 Wiley‐Liss, Inc.
Late structural alterations of cerebral white matter in long‐term survivors of childhood leukemia
Authors: Dellani Paulo R. , Eder Stefan , Gawehn Joachim , Vucurevic Goran , Fellgiebel Andreas , Müller Matthias J. , Schmidberger Heinz , Stoeter Peter , Gutjahr Peter
Published: May 2008

Purpose

To look for the presence and age‐dependence of late structural alterations of otherwise normal‐appearing cerebral gray and white matter after radiation and chemotherapy in adult survivors of acute lymphoblastic leukemia (ALL) during childhood.

Materials and Methods

In a group of 13 adult survivors 17–37 years old, who had been treated by total brain radiation (18–24 Gy) and chemotherapy 16–28 years ago, prospective MR examinations including diffusion tensor imaging (DTI) were performed. Evaluation included volumetry, calculation of mean diffusivity (MD) and fractional anisotropy (FA), and comparison of results to an age‐matched control group.

Results

DTI showed significantly reduced FA values in the temporal lobes (difference of 0.069 units, P < 0.001), hippocampi (difference of 0.033 units, P < 0.001), and thalami (difference of 0.046 units, P = 0.001), which were accompanied by significant white matter volume loss (difference of 92 cm3, P < 0.001). Significant elevations of MD were limited to the temporal white matter (difference of 42 × 10−6 mm2/s, P = 0.005). Global and frontal white matter MD correlated negatively to increasing age of the survivors (P < 0.01).

Conclusion

With regard to structural white matter alterations, adult long‐term survivors of childhood ALL, who had received total brain radiation and chemotherapy, apparently show the same overall age dependence as controls. Follow‐up studies are needed for confirmation. J. Magn. Reson. Imaging 2008;27:1250–1255. © 2008 Wiley‐Liss, Inc.
Differential interictal activity of the precuneus/posterior cingulate cortex revealed by resting state functional MRI at 3T in generalized vs. Partial seizure
Authors: Lui Su , Ouyang Luo , Chen Qin , Huang Xiaoqi , Tang Hehan , Chen Huafu , Zhou Dong , Kemp Graham J. , Gong Qiyong
Published: May 2008

Purpose

To characterize, using functional MRI (fMRI), the pattern of active brain regions in the resting state in patients with epilepsy.

Materials and Methods

We studied 28 patients with epilepsy, divided into a partial seizure (PS; N = 9) and a generalized seizure group (GS; N = 19), and 34 control subjects. Resting state fMRI was performed using a GE 3T scanner by collecting 200 volumes of echo‐planar imaging (EPI) images with subjects relaxed, eyes closed. Data were processed using a modification of the method of Fransson (Hum Brain Mapp 2005;26:15–29), which reveals information on regional low‐frequency Blood Oxygenation Level Dependent (BOLD) signal oscillations in the resting state without any a priori hypothesis. The significant active areas in brain were identified with both individual and group analysis.

Results

Controls showed active regions in the precuneus/posterior cingulate cortex (PCC) and medial prefrontal cortex (MPFC)/ventral anterior cingulate cortex (vACC), theregions associated with the brain “default mode.” Similar active regions were observed in PS, whereas GS showed no significant activation of precuneus/PCC.

Conclusion

In GS, the lack of activation in precuneus/PCC may partly account for their more severe interictal deficits, compared to PS, in cognitive functions such as concentration and memory. J. Magn. Reson. Imaging 2008;27:1214–1220. © 2008 Wiley‐Liss, Inc.
Improvement of vessel visibility in time‐of‐flight MR angiography of the brain
Authors: Shonai Takaharu , Carpenter Jeffrey S. , Lemieux Susan K. , Harada Kuniaki , Omori Kazumi , Kaneko Nobuaki , Fukushima Takanori
Published: May 2008

Purpose

To improve vessel visibility in time‐of‐flight MR angiography (TOF‐MRA) by careful consideration of coil choice, coil position, and frequency offset and profile of the nonspatially selective chemical shift selective (CHESS) presaturation pulse.

Materials and Methods

The effects of both the CHESS and the excitation radiofrequency (RF) pulses on flow signal and signals from stationary substances were evaluated by changing the spatial area where RF pulses were applied to upstream flow in a flow phantom and in human subjects. The difference between the eight‐channel phased‐array receive‐only coil and the transmit–receive coil was evaluated.

Results

The CHESS pulse suppresses the flow signal over a wider frequency range than the signals from stationary substances, especially when using the body coil for transmission. Even without presaturation pulse, the excitation pulse slightly suppressed the flow signal. Adjusting the position of the transmit–receive coil relative to the head improved these TOF‐MRA images. The results were better than those obtained with the eight‐channel coil.

Conclusion

The excitation and the nonspatially selective CHESS pulses degraded the flow signal. Our results suggest that reduced spatial extent of RF pulse application to upstream flow can improve image quality of TOF‐MRA. This result can be implemented on conventional scanners. J. Magn. Reson. Imaging 2008;27:1362–1370. © 2008 Wiley‐Liss, Inc.
Fully automatic segmentation of the brain from T1‐weighted MRI using Bridge Burner algorithm
Authors: Mikheev Artem , Nevsky Gregory , Govindan Siddharth , Grossman Robert , Rusinek Henry
Published: May 2008

Purpose

To validate Bridge Burner, a new brain segmentation algorithm based on thresholding, connectivity, surface detection, and a new operator of constrained growing.

Materials and Methods

T1‐weighted MR images were selected at random from three previous neuroimaging studies to represent a spectrum of system manufacturers, pulse sequences, subject ages, genders, and neurological conditions. The ground truth consisted of brain masks generated manually by a consensus of expert observers. All cases were segmented using a common set of parameters.

Results

Bridge Burner segmentation errors were 3.4% ± 1.3% (volume mismatch) and 0.34 ± 0.17 mm (surface mismatch). The disagreement among experts was 3.8% ± 2.0% (volume mismatch) and 0.48 ± 0.49 mm (surface mismatch). The error obtained using the brain extraction tool (BET), a widely used brain segmentation program, was 8.3% ± 9.1%. Bridge Burner brain masks are visually similar to the masks generated by human experts. Areas affected by signal intensity nonuniformity artifacts were occasionally undersegmented, and meninges and large sinuses were often falsely classified as the brain tissue. Segmentation of one MRI dataset takes seven seconds.

Conclusion

The new fully automatic algorithm appears to provide accurate brain segmentation from high‐resolution T1‐weighted MR images. J. Magn. Reson. Imaging 2008;27:1235–1241. © 2008 Wiley‐Liss, Inc.
Sex differences in language processing: Functional MRI methodological considerations
Authors: Harrington Greg S. , Farias Sarah Tomaszewski
Published: May 2008

Purpose

To evaluate the influence of both analysis methods and tasks used in the determination of language related sex differences. Previous neuroimaging studies evaluating sex differences in language processing have been inconsistent.

Materials and Methods

The current study compared FMRI activation between men and women on a variety of language tasks using different types of individual (laterality and activation volume) and group analyses to evaluate the effects of task and methodology. Forty subjects completed five language tasks, 19 men and 21 women.

Results

Group analyses revealed greater activation for men compared with women in the left pars orbitalis while women showed greater activation within the right insula. With individual analyses, there were no significant sex differences in laterality using two large regions of interest (ROIs) covering the inferior frontal and temporoparietal regions; however, there were significant sex effects within small, specific ROIs (insula, middle temporal and pars opercularis, triangularis, and orbitalis). When holding the task constant, some methods (for example different ROIs within individual analyses) revealed sex differences while others methods did not, indicating a dependence on methodology.

Conclusion

The results partly explain why FMRI studies evaluating language related sex effects have been inconsistent. J. Magn. Reson. Imaging 2008;27:1221–1228. © 2008 Wiley‐Liss, Inc.
Temporal evolution of MR perfusion in neonatal hypoxic‐ischemic encephalopathy
Authors: Wintermark Pia , Moessinger Adrien C. , Gudinchet François , Meuli Reto
Published: May 2008

Purpose

To illustrate the evolution of brain perfusion‐weighted magnetic resonance imaging (PWI‐MRI) in severe neonatal hypoxic‐ischemic (HI) encephalopathy, and its possible relation to further neurodevelopmental outcome.

Materials and Methods

Two term neonates with HI encephalopathy underwent an early and a late MRI, including PWI. They were followed until eight months of age. A total of three “normal controls” were also included. Perfusion maps were obtained, and relative cerebral blood flow (rCBF) and cerebral blood volume (rCBV) values were measured.

Results

Compared to normal neonates, a hyperperfusion (increased rCBF and rCBV) was present on early scans in the whole brain. On late scans, hyperperfusion persisted in cortical gray matter (normalization of rCBF and rCBV ratios in white matter and basal ganglia, but not in cortical gray matter). Diffusion‐weighted imaging (DWI) was normalized, and extensive lesions became visible on T2‐weighted images. Both patients displayed very abnormal outcome: Patient 2 with the more abnormal early and late hyperperfusion being the worst.

Conclusion

PWI in HI encephalopathy did not have the same temporal evolution as DWI, and remained abnormal for more than one week after injury. This could be a marker of an ongoing mechanism underlying severe neonatal HI encephalopathy. Evolution of PWI might help to predict further neurodevelopmental outcome. J. Magn. Reson. Imaging 2008;27:1229–1234. © 2008 Wiley‐Liss, Inc.
EVP‐ABD‐enhanced MRI to evaluate diffuse liver disease in a rat model
Authors: Zuo Chun S. , Seoane Peter R. , Thomsen Morgane , Gillis Tim , Meloni Edward , Harnish Phillip P. , Renshaw Perry F.
Published: May 2008

Purpose

To evaluate the feasibility of using manganese‐based MR imaging contrast agent EVP‐ABD to detect diffuse liver disease in an established rat hepatitis model.

Materials and Methods

Hepatitis was induced by administration of CCl4in corn oil vehicle to rats intraperitoneally. MR images were acquired on a 3T scanner using a volume coil ≈36 hours after the administration of CCl4. EVP‐ABD was administered via a tail vein at a dose of 10 μmol/kg. Multi‐TI turboflash images were acquired to evaluate liver R1 (=1/T1) values before and after the EVP‐ABD administration. Eighteen rats received various doses of CCl4and completed pre‐ and postcontrast MRI scans and liver histologic evaluation.

Results

The liver R1 after the EVP‐ABD administration and the change of the liver R1 before and after the administration, ΔR1, show significant correlations with the CCl4dose. A significant correlation was also found between the histologic scores and the CCl4doses despite known variability in the relationship of CCl4dose to histology. A significant correlation was found between the histologic score and ΔR1.

Conclusion

Our results indicate that EVP‐ABD‐enhanced MRI can detect diffuse liver disease generated by CCl4based on the significant correlation between proton R1 in liver following EVP‐ABD and the CCl4doses as well as the histologic scores. J. Magn. Reson. Imaging 2008;27:1317–1321. © 2008 Wiley‐Liss, Inc.
Prostate MR imaging at 3T with a longitudinal array endorectal surface coil and phased array body coil
Authors: Kim David Y. , Schnall Mitchell D. , Rosen Mark A. , Connick Thomas
Published: May 2008

Purpose

To demonstrate the feasibility of using a double loop phased array endorectal coil combined with a phased array body coil to image the prostate at 3T.

Materials and Methods

We designed and constructed a novel prostate coil employing two arrayed 4.0 × 5.0 cm loops, tuned the device for optimal performance at 3T, and characterized the signal‐to‐noise ratio (SNR) associated with it.

Results

The coil Q factor was calculated to be ≈50 unloaded, and 30 when loaded on human tissue. SNR maps at multiple orientations were constructed and images were acquired on both a phantom and a human. As expected, SNR was highest along the midpoint of the array and demonstrated strong signal even at 4 cm from the coil.

Conclusion

The double loop phased array endorectal coil combined with a phased array body coil at 3T is feasible in vivo and compelling enough to warrant future clinical trials to evaluate its efficacy. These trials are currently under way. J. Magn. Reson. Imaging 2008;27:1327–1330. © 2008 Wiley‐Liss, Inc.
Contrast‐enhanced timing robust acquisition order with a preparation of the longitudinal signal component (CENTRA plus) for 3D contrast‐enhanced abdominal imaging
Authors: Beck Gabriele M. , De Becker Jan , Jones Alun C. , von Falkenhausen Marcus , Willinek Winfried A. , Gieseke Jürgen
Published: May 2008

Purpose

To investigate a new image acquisition method that enables an accurate hepatic arterial phase definition and the visualization of contrast agent uptake processes in abdominal organs like liver, spleen, and pancreas.

Materials and Methods

A 3D turbo gradient echo method where a fat suppression prepulse is followed by the acquisition of several profiles was combined with an elliptical centric k‐space ordering technique and 3D dynamic elliptical centric keyhole. The new k‐space ordering method (CENTRA+) was validated experimentally. In an initial clinical evaluation phase the method was employed in five patients to assess the accuracy of the hepatic arterial phase definition and the visualization of the contrast uptake processes in dynamic scanning in abdominal organs like liver, spleen, and pancreas.

Results

In total, five patients were evaluated using the new k‐space order. Our initial results indicate that the new k‐space order allows consistent capture of the hepatic arterial phase. In dynamic scanning the extreme short temporal resolution obtained with 3D elliptical centric keyhole enables contrast enhancement to be followed in organs with fast contrast uptake characteristics.

Conclusion

The elliptical centric nature of the new image acquisition method effectively allows capture of the contrast enhancement processes with good fat suppression. J. Magn. Reson. Imaging 2008;27:1461–1467. © 2008 Wiley‐Liss, Inc.
Finite‐difference time‐domain analysis of radiation characteristics of monopoles on space probes
Authors: Zunoubi Mohammad R. , Kalhor Hassan A.
Published: May 2008

A general numerical solution based on finite‐difference time‐domain (FDTD) is presented to calculate the radiation characteristics of wire antennas on space probes. The method is versatile and can treat conductor loss, arbitrary‐shaped probes, and wires as well as inhomogenities. Numerical results are obtained and compared with those for a few specific cases available in the literature. Additionally, laboratory models of the antennas have been built and their properties have been measured for comparison with computed results. Copyright © 2008 John Wiley & Sons, Ltd.
The coastal winds off western subtropical South America in future climate scenarios
Authors: Garreaud René D. , Falvey Mark
Published: May 2008

The west coast of subtropical South America is characterized by a semi‐arid climate and very persistent southerly winds that often exhibit a low‐level jet structure. The nearly alongshore flow forces coastal and offshore upwelling of cold, nutrient‐rich waters, thus supporting one of the most productive marine ecosystems in the world and a wealth of fishery resources. Therefore, the evaluation of the changes in the coastal winds in future climate is a key step to predict the regional environmental impacts of global climate change linked to anthropogenic greenhouse gas (GHG) increases.

In this work we document the wind changes between present‐day conditions and those projected for the end of the 21st century under two Intergovernmental Panel on Climate Change (IPCC) scenarios (A2 and B2). We first estimate and interpret the changes of the wind field over the southeast Pacific from 15 coupled atmosphere–ocean Global Circulation Models (GCMs). Very consistent among the GCMs is the strengthening of the southerlies along the subtropical coast as a result of a marked increase in surface pressure farther south. We then examine the coastal wind changes in more detail using the Providing REgional Climate for Impact Studies (PRECIS) regional climate model (RCM) with 25 km horizontal resolution nested in the Hadley Centre Atmospheric global Model (HadAM3). PRECIS results indicate that the largest southerly wind increase occurs between 37–41°S during spring and summer, expanding the upwelling‐favourable regime in that region, at the same time that coastal jets at subtropical latitudes will become more frequent and last longer than current events. During fall and winter, the strengthening of the southerlies occurs at subtropical latitudes maintaining a mean jet year‐round. Finally, we discuss the possibility that strengthening of the coastal southerlies might actually lead to a relative regional cooling even as the world as a whole continues to warm up. Copyright © 2008 Royal Meteorological Society
Examination of pigments on Thai manuscripts: the first identification of copper citrate
Authors: Eremin Katherine , Stenger Jens , Huang Jo‐Fan , Aspuru‐Guzik Alan , Betley Theodore , Vogt Leslie , Kassal Ivan , Speakman Scott , Khandekar Narayan
Published: May 2008

Samples from Thai manuscripts dated to the 18th to 20th century were analyzed by Raman spectroscopy and Fourier‐transform infrared spectroscopy (FTIR) to determine the pigments used. This suggested a change in palette from the 18th to 20th century, with use of imported pigments in the later manuscripts. In the 18th century, the main green used was an organic copper salt, which was replaced by emerald green and mixtures of Prussian blue with gamboge, chrome yellow and zinc yellow (zinc potassium chromate). Chrome yellow was used in addition to gamboge in one later 19th century manuscript. Similarly, indigo in the 18th century manuscripts was replaced by Prussian blue and then synthetic ultramarine in the 19th century manuscripts.

Lead white was the main white pigment in all but one manuscript, which contained huntite, a magnesium calcium carbonate. Huntite also occurred in mixtures with other pigments in two other manuscripts. In all the works studied, red lead, vermilion and red earth were used for red, orange and pink shades and red earth in brown areas.

The organic copper salt used in the 18th century gave good FTIR spectra but could not initially be matched with any published compound. X‐ray diffraction (XRD) suggested this was a copper citrate phase, and examination of the literature showed that the FTIR spectra matched those published for a hydrated copper citrate. Raman spectra were obtained from this organic copper salt, which showed close agreement with those obtained from synthetic copper citrate. Copper citrate has not been identified previously as an artist's material, although its use has been postulated on the basis of historical texts. Minor copper formate and/or copper chloride were also identified by XRD and scanning electron microscopy (SEM) in some green samples containing copper citrate. Copyright © 2008 John Wiley & Sons, Ltd.
New developments in nonlinear spectroscopy: ECONOS meeting in St. Petersburg
Authors: Zheltikov A. M. , Radi P. P.
Published: May 2008

The sixth European Conference on Nonlinear Optical Spectroscopy(ECONOS) took place in St. Petersburg, Russia, in May 2007. This special issue includes ten contributions from ECONOS authors, presenting the latest developments and achievements in nonlinear optical spectroscopy. Copyright © 2008 John Wiley & Sons, Ltd.
Pre‐ or post‐harvest applications of putrescine and low temperature storage affect fruit ripening and quality of ‘Angelino’ plum
Authors: Khan Ahmad S , Singh Zora , Abbasi Nadeem A , Swinny Ewald E
Published: May 2008

BACKGROUND: Plum has a very short storage life. The role of pre‐ or post‐harvest applications of putrescine (PUT) and low temperature storage on fruit ripening and quality was investigated in plum fruit (Prunus salicina Lindl. cv. Angelino).

RESULTS: Pre‐ or post‐harvest PUT treatments [(0.1, 1.0 or 2.0 mmol L−1) + 0.01% Tween‐20 as a surfactant] delayed and suppressed the climacteric ethylene production and respiration rate irrespective of the method used to apply PUT. PUT‐treated fruit following low temperature storage (0 ± 1 °C; 90 ± 5% RH), at the ripe stage exhibited higher fruit firmness and titratable acidity (TA), while soluble solids content (SSC), levels of ascorbic acid, total carotenoids and total antioxidants were lower than in untreated fruit. Fruit both sprayed with PUT and stored in low temperature for 6 weeks, at the ripe stage showed reduced respiration rate, delayed changes in the SSC:TA ratio and levels of total carotenoids compared to post‐harvest PUT application.

CONCLUSION: Pre‐harvest application of 2.0 mmol L−1 PUT 1 week before the anticipated commercial harvest was more effective in delaying plum fruit ripening and can be used to extend the storage (0 ± 1 °C) life of plums for up to 6 weeks with minimum losses in fruit quality. Copyright © 2008 Society of Chemical Industry
Effects of agricultural practices on instrumental colour, mineral content, carotenoid composition, and sensory quality of mandarin orange juice, cv. Hernandina
Authors: Beltrán‐González Felipe , Pérez‐López Antonio J , López‐Nicolás José M , Carbonell‐Barrachina Ángel A
Published: May 2008

BACKGROUND: Frequent consumption of fruits and vegetables is associated with a lowered risk of cancer, hypertension and heart disease, due, among other factors such as modulation of gene expression and improvement of gap junctional communication, to the presence of various forms of antioxidants present in the foods as carotenoids. Otherwise, consumers demand organic products which they believe have more flavour and are of greater benefit to the environment and human health. The effects of organic farming on CIE L*a*b* colour, mineral content, carotenoid composition and sensory quality of Hernandina mandarin juices were studied.

RESULTS: Organic farming of mandarin oranges resulted in juices with higher contents of minerals and carotenoids, and of better sensory quality. For instance, organic juice contained a total concentration of carotenoids of 14.4 mg L−1 compared to 10.2 mg L−1 of conventional juice.

CONCLUSION: Mandarin orange juices can be considered as a good source of some important nutrients, such as potassium and antioxidant chemicals, e.g. β‐cryptoxanthin. Copyright © 2008 Society of Chemical Industry
Covalent interactions between amino acid side chains and oxidation products of caffeoylquinic acid (chlorogenic acid)
Authors: Prigent Stéphanie VE , Voragen Alfons GJ , Li Feng , Visser Antonie JWG , van Koningsveld Gerrit A , Gruppen Harry
Published: May 2008

BACKGROUND: Physicochemical properties and digestibility of proteins can be modified by covalent interactions with oxidized phenolic compounds, i.e., quinones. In order to control these interactions in food products, the covalent interactions between quinones from caffeoylquinic acid (CQA) and amino acid side chains were studied with mass spectrometry using N‐terminally protected amino acids.

RESULTS: The addition of two molecules of CQA, presumably in the form of a pre‐formed dimer, was observed for lysine, tyrosine, histidine and tryptophan. A monomer of CQA seemed to be able to react with histidine and tryptophan, whereas no interaction with a CQA monomer was observed for lysine and tyrosine. Serine and threonine showed no covalent interactions with CQA. Cross‐linking between CQA and the side chains of two molecules of lysine is likely to occur also in proteins. The results show that protein cross‐linking may also be expected to occur via two tyrosine residues in the absence of other phenolic substrates. The side chains of lysine and tyrosine are more reactive than that of histidine and tryptophan.

CONCLUSIONS: These results show that covalent protein modification by oxidized phenolics occurs preferentially via an initial dimerization and encompasses not only lysine and cysteine residues. Copyright © 2008 Society of Chemical Industry
Optimization of processing of fresh‐cut pear
Authors: Arias Esther , González Jaime , López‐Buesa Pascual , Oria Rosa
Published: May 2008

BACKGROUND: Successful processing of pears to render fresh‐cut fruits requires a thorough knowledge of their sensitivity to browning reactions, their respiratory metabolism, and their behaviour under modified atmosphere packaging.

RESULTS: First, three different varieties of pear (Williams, Conference, Passacrassana) that had reached their commercial ripening stage were evaluated for suitability for minimal processing. Two antioxidant treatments were tested (treatment 1: 2% ascorbic acid + 1% citric acid + 1% CaCl2; treatment 2: 2% ascorbic acid + 0.01% 4‐hexylresorcinol + 1% CaCl2) to decide which one was the most effective against enzymatic browning. Finally, a modified atmosphere packaging was designed after two previous tests: measurement of respiratory activity of the peeled and cut pear at three temperatures (4, 15 and 25 °C); and evaluation of fruit tolerance to three different atmospheric compositions (21% O2 + 10% CO2; 2% O2 + 0% CO2; 2% O2 + 10% CO2).

CONCLUSIONS: Conference pear was found to be the most suitable variety. Among the antioxidant treatments the one consisting of ascorbic acid, 4‐hexylresorcinol and CaCl2 was proven to be the most effective against browning. The samples were packaged in a modified atmosphere with a composition of 10% O2 + 10% CO2 + 80% N2. Copyright © 2008 Society of Chemical Industry
Gelatin/PLLA Sponge‐Like Scaffolds Allow Proliferation and Osteogenic Differentiation of Human Mesenchymal Stromal Cells
Authors: Mattii Letizia , Battolla Barbara , D'Alessandro Delfo , Trombi Luisa , Pacini Simone , Cascone Maria Grazia , Lazzeri Luigi , Bernardini Nunzia , Dolfi Amelio , Galimberti Sara , Petrini Mario
Published: May 2008

Tissue engineering has the potential to supply constructs capable of restoring the normal function of native tissue following injury. Poly(L‐lactic acid) (PLLA) scaffolds are amongst the most commonly used biodegradable polymers in tissue engineering and previous studies performed on ovine fibroblasts have showed that addition of gelatin creates a favorable hydrophilic microenvironment for the growth of these cells. The attractiveness of using mesenchymal stromal cells (MSCs) in tissue regeneration is that they are able to differentiate into several lines including osteoblasts. In this study, we investigated the ability of gelatin/PLLA sponges to support the adhesion, proliferation, and osteogenic differentiation of human MSCs isolated from the bone marrow of four donors.

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Ethylene/4‐Methyl‐1‐pentene Copolymers by a “Constrained Geometry Catalyst”: Advances in 13C NMR Assignment
Authors: Losio Simona , Boccia Antonella C. , Sacchi Maria Carmela
Published: May 2008

Ethylene/4‐methyl‐1‐pentene (E/4M1P) copolymers were synthesized by [Me2Si(η5‐Me4C5)‐(η1‐N‐tBu)TiCl2] and methylalumoxane (MAO) catalyst (CG) and analyzed by 13C NMR. The low regio‐ and stereoregularity of CG leads to spectral multiplicities which can be ascribed not only to differences in comonomer sequences but also to the presence of regio‐ and stereoirregularities. The tendency of CG to give a nearly random comonomer distribution gives rise to so far undetectable alternating sequences. The complete set of assignments proposed allows a satisfactory characterization of variously microstructured E/4M1P copolymers and the evaluation of the amount of regioirregular sequences in addition to the full determination of dyad and triad copolymer composition.

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Ultra‐Small‐Angle X‐Ray Scattering Study of PET/PC Nanolayers and Comparison to AFM Results
Authors: Ania Fernando , Puente‐Orench Inés , Baltá Calleja Francisco J. , Khariwala Devang , Hiltner Anne , Baer Eric , Roth Stephan V.
Published: May 2008

The forced assembly of two immiscible polymers, produced by layer‐multiplying co‐extrusion, is analyzed by means of USAXS. Comparison of scattering and AFM results sheds light on many details of the nanolayered structure in PET/PC films. The role played by the volume concentration and cold crystallization of PET on the experimental scattering is discussed. The appearance of at least two scattering maxima in all cases, corresponding to higher orders of the same repeating distance, accounts for the high regularity of the developed nanostructure. It is finally shown that long spacing values, derived from a localized area in AFM, are in a good agreement with the USAXS values averaged over much larger areas.

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Smooth Surface Polypyrrole‐Silica Core‐Shell Nanoparticles: Preparation, Characterization and Properties
Authors: Marini Michele , Pilati Francesco , Pourabbas Behzad
Published: May 2008

Polypyrrole‐silica nanoparticles were prepared by in situ polymerization of pyrrole monomer in the presence of specially modified silica nanoparticles having vinyl functional groups on the surface. The presence of polypyrrole (PPy) on the surface of silica nanoparticles was confirmed using FT‐IR spectroscopy. The core‐shell morphology was analyzed by TEM. A uniform and smooth shell of PPy on the silica nanoparticles and absence of free PPy homopolymer were the main features of the proposed method that employs modified silica nanoparticles for the synthesis of the PPy‐coated silica nanoparticles. SEM investigation of the particles deposited on a glass surface showed a narrow size distribution with an average diameter of 240 nm for the particles. The weight percentage of PPy was estimated using TGA and DSC to be approximately 10 wt.‐%. Further investigations a by two‐probe conductivity method of glass slides coated with the nanoparticles showed an electrical conductivity of 7 S · cm−1. The static water contact angle was as high as 169 °.

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Milder Changes in Chemistry Make a Significant Difference in Phase Transition Temperatures for Triblock Copolymers on PEO106‐PPO70‐PEO106 Block Copolymer Chains
Authors: Zhang Chi , Easteal Allan J.
Published: May 2008

Here we report a simple oxidative route to making triblock copolymers with significantly higher phase transition temperatures than their precursor analogs at the same wt.‐% in water. This may be the easiest way to tune the phase transition temperatures of other analogs of Pluronic copolymers. Self‐capped triblock copolymers were synthesized, starting with Pluronic F127, using a milder selective oxidizer, to confer a near one‐fold increase in phase transition temperatures and alternative textures of the hydrogel surface in 30 wt.‐% copolymer. Comparison between the Pluronic triblock copolymer F127 and the end‐capped triblock copolymers was carried out using XPS, XRD, FT‐IR, environmental scanning electron microscopy (ESEM), polarization microscopy (PM) and NMR, though the change in chemistry was small. The present work provides a paradigm that a long macromolecular chain with a slightly modified chemistry may lead to huge alterations in the properties of materials which have potential applications in environmental monitoring, sensors, tissue engineering, artificial skin and drug delivery, particularly in injectable gel delivery systems.

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An H‐Bonded Main‐Chain Liquid‐Crystalline Polymer Obtained by In Situ Photochemical Conversion from an H‐Bonded LC Dimer
Authors: Kihara Hideyuki , Tamaoki Nobuyuki
Published: May 2008

An H‐bonded main‐chain liquid‐crystalline (LC) polymer was obtained by in situ photochemical conversion from an H‐bonded LC dimer. A bifunctional compound, 1, having a cinnamoyl group at one end and a carboxylic acid group at the other, was synthesized as the H‐bonded LC dimer. UV irradiation of 1 in the LC phase in the presence of a sensitizer resulted in its conversion to a photodimer, with a carboxylic acid at both ends, through photocycloaddition of the cinnamoyl moiety. The LC phase was maintained during irradiation, because that of the photodimer was more thermally stable than that of 1. FT‐IR analysis revealed that the carboxylic acids of the photodimer dominantly formed hydrogen bonds in the LC phase, which suggests that the photodimers assembled into an H‐bonded main‐chain LC polymer.

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Ethylene–Propylene–Silsesquioxane Thermoplastic Elastomers
Authors: Seurer Bradley , Coughlin E. Bryan
Published: May 2008

Preparative methods for the incorporation of polyhedral oligomeric silsesquioxane (POSS) macromonomers into ethylene–propylene (EP) polymers have been developed that utilize metallocene polymerization. Analysis of these novel ethylene–propylene–POSS polymers using wide‐angle X‐ray diffraction reveals that pendant POSS groups off the polymer backbones aggregate with a phenyl periphery, and the polymers crystallize as anisotropically shaped nanocrystals. POSS particle aggregation is strongly dependent on the nature of the POSS peripheral group. X‐Ray studies suggest that aggregation of POSS in the EP elastomers did not occur with isobutyl and ethyl peripheries, as they disperse within the polymer matrix. The formation of POSS nanocrystals increases the mechanical properties of these thermoplastic elastomers. The tensile storage modulus increases significantly with the addition of POSS, as does the length of the rubbery plateau region. Tensile studies reveal an elongation at break of 720% for one EP‐phenyl POSS polymer sample, with the others between 400 and 500%.

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Swelling Deswelling Behavior of PS‐PNIPAAM Copolymer Particles and PNIPAAM Brushes Grafted from Polystyrene Particles & Monoliths
Authors: Mittal Vikas , Matsko Nadejda B. , Butté Alessandro , Morbidelli Massimo
Published: May 2008

Two sets of emulsion particles have been synthesized. In the first set, surfactant free emulsion was used to directly synthesize PS‐PNIPAAM copolymer particles. In the second set, polystyrene particles with an ATRP initiator shell were first synthesized and subsequently grafted with PNIPAAM brushes. Swelling/deswelling behavior of both sets of particles was studied with respect to temperature and time. Monoliths with two different porosities were also formed by grafting and crosslinking of PNIPAAM chains on the aggregated particles and characterized. In all cases, swelling kinetics is sufficiently fast to use these supports for separation driven by temperature changes only. However, hindrance and cross‐linking is sensibly reducing the material performance.

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Sonochemical Synthesis of Magnetic Protein Container for Targeted Delivery
Authors: Han Yongsheng , Radziuk Darya , Shchukin Dmitry , Moehwald Helmuth
Published: May 2008

A new targeted delivery system was developed in this paper by depositing magnetic NPs on protein containers which were prepared by sonicating oil in a protein solution. The deposition was conducted by layer‐by‐layer technique and monitored by zeta potential measurement. Such prepared samples can be targeted delivery in an external magnetic field. The hydrophobic dye TPP, as a model of drug, was loaded in the containers by dissolution in the oil phase before sonication. The containers loaded with dye are stable and can sustain the deposition treatment without loss of dye due to the protection of protein nanoshells.

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Structure–Reactivity Correlation in “Click” Chemistry: Substituent Effect on Azide Reactivity
Authors: Golas Patricia L. , Tsarevsky Nicolay V. , Matyjaszewski Krzysztof
Published: May 2008

An investigation was conducted into substituent effects on azide reactivity during CuI‐catalyzed click reactions by reacting a variety of model azides with propargyl alcohol in DMF‐d7 using CuBr as catalyst, and monitoring conversions via 1H NMR. The model azides utilized for this investigation were selected due to structural similarity with the end groups of polymers typically employed in azide‐alkyne cycloadditions including polystyrene, poly(methyl acrylate), poly(methyl methacrylate), and polyacrylonitrile. Reactivities of alkyl azides depend on both the electronic properties of the substituent and steric congestion around the end group. The fastest reactions were observed for azides with electron‐withdrawing substituents and less sterically congested end groups.

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The Introduction of Pyrrolotetrathiafulvalene into Conjugated Architectures: Synthesis and Electronic Properties
Authors: Kanibolotsky Alexander L. , Forgie John C. , Gordeyev Sergey , Vilela Filipe , Skabara Peter J. , Lohr Jan E. , Petersen Bo M. , Jeppesen Jan O.
Published: May 2008

A series of new conjugated copolymers incorporating the redox‐active pyrrolo‐TTF unit has been synthesised. The properties of the polymers have been investigated by cyclic voltammetry and electronic absorption spectroscopy, revealing that the pyrrolo‐TTF behaves very differently to its thieno‐TTF variant. In comparison to thieno analogues, the band gaps of the new polymers are wider than expected due to a decrease in the polarizability of the heteratom (nitrogen vs. sulfur) and steric interactions between repeat units. Whilst the pyrrolo‐TTF units are stronger electron donors than thieno‐TTFs in related structures, the two redox active elements of the new polymers (TTF and conjugated chain) function independently under oxidative conditions.

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Micro‐Raman and Tip‐Enhanced Raman Spectroscopy of Carbon Allotropes
Authors: Hoffmann Günter G. , de With Gijsbertus , Loos Joachim
Published: May 2008

Summary: Raman spectroscopic data are obtained on various carbon allotropes like diamond, amorphous carbon, graphite, graphene and single wall carbon nanotubes by micro‐Raman spectroscopy, tip‐enhanced Raman spectroscopy and tip‐enhanced Raman spectroscopy imaging, and the potentials of these techniques for advanced analysis of carbon structures are discussed. Depending on the local organisation of carbon the characteristic Raman bands can be found at different wavenumber positions, and e.g. quality or dimensions of structures of the samples quantitatively can be calculated. In particular tip‐enhanced Raman spectroscopy allows the investigation of individual single wall carbon nanotubes and graphene sheets and imaging of e.g. local defects with nanometer lateral resolution. Raman spectra of all carbon allotropes are presented and discussed.
Planar Array Transient Infrared Spectroscopy: A New Tool for the Time‐Resolved Analysis of Polymers
Authors: Pellerin Christian
Published: May 2008

Summary: Planar array infrared spectroscopy (PA‐IR) was used for the first time to record transient infrared (TIRS) spectra. In proof‐of‐concept experiments, it was demonstrated that PA‐TIRS can record high quality spectra of common polymeric samples. It was shown the this new technique allows acquiring spectra in as little as 17 ms, opening the door to high speed, real‐time monitoring applications.