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To investigate the formation and evolution mechanisms of nano-clusters formed during the rapid solidification process, a molecular dynamics (MD) simulation study has been performed for a system consisting of 10 6 atoms of Cu 64.5 Zr 35.5 alloy. Adopting a new cluster-type index method (CTIM-3) to analyse the local atomic clusters, it is found that the dominant microstructural configurations in the supercooled liquid and amorphous are the icosahedrons and their combinations, especially the intercross-sharing (IS) clusters linked of two icosahedrons (IS-ICO-clusters) can be used to build some larger IS-ICO nano-clusters with different sizes. Highly interesting, in the system the number of atoms in various IS-ICO nano-clusters demonstrates a magic number sequence of 19, 23, 25, 27, 29, 31, 33, 35, 37, 41, 43, and so on. The magic number clusters can be classified into three main types: chain-like, triangle-tailed and quadrilateral-tailed. The degree of tightness for IS-ICO nano-cluster can be expressed by formula n I / n IS . And some IS-ICO nano-structures have stronger mechanical stability and can bear higher load. [ABSTRACT FROM AUTHOR]

Highlights: [•] Memory cells containing chemically-synthesized FePt nanocrystals are fabricated. [•] A hexagonal arrangement monolayer is self-assembled on alumina by dip-coating. [•] The core–shell structure is formed with alloy core and amorphous iron oxide shell. [•] The MOS capacitors are electrically measured exhibiting obvious memory effects. [ABSTRACT FROM AUTHOR]

Abstract: Self-assembled face-centered cubic FePt nanoparticles were capped by a amorphous Al2O3 capping layer with the thickness of 10nm using the atomic layer deposition (ALD) technology, and transmission electron microscopy indicates that the FePt nanocrystals are well-separated. After annealing the composite film at 700°C, well-monodispersed face-centered tetragonal FePt particles can be obtained, yielding a coercivity value Hc=5.9kOe with the magnetocrystalline anisotropy of 3.86MJ/m3. The thermal factor for the composite film is 68.5, meeting the industry requirement (K u V/k B T ≥ 50). The protection of amorphous Al2O3 matrix can effectively inhibit grain growth and particle aggregation, and preserve the ordered domains of FePt nanoparticles during the L10 ordering transition. The combination of ALD-capping layer and self-assembled FePt nanoparticles provides a new potential approach to fabricate patterned magnetic recording media with ultrahigh areal density. [Copyright &y& Elsevier]

Abstract: Objective: To explore the effects of particulate matters less than 2.5 μm in aerodynamic diameter (PM2.5) on heart repolarization/depolarization and heart rate variability (HRV). Methods: We conducted a panel study for elderly subjects with heart disease in Beijing from 2007 to 2008. PM2.5 was measured at a fixed station for 20 h continuously each day while electrocardiogram (ECG) indexes of 42 subjects were also recorded repeatedly. Meteorological data was obtained from the China Meteorological Data Sharing Service System. A mixed linear regression model was used to estimate the associations between PM2.5 and the ECG indexes. The model was adjusted for age, body mass index, sex, day of the week and meteorology. Results: Significant adverse effects of PM2.5 on ECG indexes reflecting HRV were observed statistically and the strongest effect of PM2.5 on HRV was on lag 1 day in our study. However, there were no associations between PM2.5 and ECG indexes reflecting heart repolarization/depolarization. Additionally, the effects of PM2.5 on subjects with hypertension were larger than on the subjects without hypertension. Conclusion: This study showed ambient PM2.5 could affect cardiac autonomic function of the elderly people with heart disease, and subjects with hypertension appeared to be more susceptive to the autonomic dysfunction induced by PM2.5. [Copyright &y& Elsevier]

Abstract: FePt nanoparticles (NPs) have been encapsulated in the insulating and protective oxide matrix, using a sol–gel process, in order to prevent particles from agglomerating and sintering during the heat-treatment process required for the L10 ordering. The microstructural and ferromagnetic properties of FePt/TiO2 nanocomposites were characterized. The presence of oxide-matrix leads to more homogeneous microstructures and better magnetic properties. The short range positional order of the FePt NPs can be preserved upon annealing at 700°C to possess higher room-temperature coercivities (HC =3.7kOe). Such nanocomposites with assemblies of high-coercivity magnetic nanoparticles are attractive for realizing new types of ultra-high-density data storage devices and magneto-composites. [Copyright &y& Elsevier]

Abstract: We studied the quality and internal changes in Huanghua pears (Pyrus pyrifolia Nakai, cv. Huanghua) coated with shellac, Semperfresh™ (sucrose polyester base coating), and carboxymethyl chitosan (CMC) during cold storage (4°C). The changes in respiration rate, weight loss, cell membrane permeability and texture profile analysis (TPA) such as hardness, brittleness and chewiness were recorded periodically for up to 60 days after harvest to compare the effects of the applied coatings. Magnetic resonance (MR) imaging was used to inspect the internal characteristics of pears after storage. The soluble solids contents (SSCs), titratable acidity (TA), ascorbic acid concentration, and taste scores were also measured. Our data suggest that shellac coating was more effective in reducing the respiration rate and weight loss and in maintaining the quality of pears than Semperfresh and CMC coatings. [Copyright &y& Elsevier]

Purpose: To evaluate the safety and diagnostic accuracy of computed tomographic (CT)-guided core needle biopsy (CNB) in the diagnosis of pancreatic diseases by using an automated biopsy gun with a cutting-type needle. Materials and Methods: From January 2000 to January 2006, CT-guided CNB was performed in 80 patients suspected of having pancreatic diseases in the absence of liver metastasis. Biopsies were performed with an 18–20-gauge cutting needle driven by a spring-loaded biopsy gun. Histologic reports and medical records of all patients were retrospectively reviewed. An institutional review board exemption was obtained to perform this retrospective study. Results: All patients tolerated the biopsies well, with no serious complications. Three patients had mild abdominal pain after the procedure, and a limited abdominal CT scan did not reveal any marked abnormality. Two patients had an elevated serum amylase level, which returned to normal within 2 weeks. A definitive diagnosis and accurate histologic diagnosis were obtained for 69 patients, for a successful diagnosis rate of 86%. Surgical sampling was performed in 11 patients with neoplasms and nondiagnostic core-needle biopsies. Only 50% of patients with well-differentiated adenocarcinomas were definitely diagnosed with CT-guided CNB. Conclusions: CT-guided CNB with an automated biopsy gun is a safe and effective method for obtaining tissue for the histologic evaluation of pancreatic diseases. However, CT-guided CNB requires further development for the accurate diagnosis of well-differentiated adenocarcinomas. [Copyright &y& Elsevier]

Abstract: Purpose: To potentiate the anticancer activity of paclitaxel-loaded PLGA nanoparticles through surface conjugation with wheat germ agglutinin (WGA). Methods: PLGA nanoparticles loaded with paclitaxel and isopropyl myristate (IPM) as release modifier were prepared by a solvent evaporation method. WGA was conjugated to the nanoparticle surface to give novel WIT-NP of 330±3 nm. In vitro cytotoxicity of WIT-NP against malignant (A549 and H1299) and normal (CCL-186) pulmonary cell lines was evaluated alongside control formulations. IC50 doses were determined by the MTT assay, while cellular apoptosis was detected by cell nuclei staining and DeadEnd™ Fluorometric TUNEL assay. Cell cycle arrest was confirmed by flow cytometry. Cellular uptake of 3[H]-paclitaxel from the test and control formulations was also quantified. In vivo anticancer efficacy was evaluated in the SCID mice model engrafted with the A549 tumor nodule. Results: WIT-NP had superior anti-proliferation activity against the A549 and H1299 cell lines compared with conventional paclitaxel formulations as measured by IC50 doses. This was attributed to a more efficient intracellular accumulation of paclitaxel via WGA-receptor-mediated endocytosis and IPM-facilitated intracellular paclitaxel release. WIT-NP activity was associated with paclitaxel-induced apoptosis and cell arrest in the G2/M phase. A single intratumoral injection of WIT-NP at paclitaxel dose of 10 mg/kg inhibited the growth of A549 tumor nodules without inducing significant weight loss in the SCID mice over a period of 25 days. Tumor doubling time was greater than 25 days, compared with 11 days for nodules treated with conventional paclitaxel formulation. Conclusion: The formulation of WIT-NP, in which WGA is conjugated to the surface of paclitaxel and IPM-loaded PLGA nanoparticles, significantly potentiates the anticancer activity of paclitaxel. [Copyright &y& Elsevier]

Abstract: The purpose of this study was to develop a novel lectin-conjugated isopropyl myristate (IPM)-incorporated PLGA nanoparticle system (NP) for the local delivery of paclitaxel to the lungs. Wheat germ agglutinin (WGA) was conjugated onto preformed IPM- and paclitaxel-loaded PLGA NPs by a two-step carbodiimide method following comparative uptake studies of Concanavalin A, Ricinus communis-120 and WGA on A549, H1299 and CCL-186 cells. WIT-NP with mean diameter of 331 nm and zeta potential of −4.3 mV were prepared with yield of 66% and paclitaxel encapsulation efficiency of 61%. Particle size was expanded by surface conjugation with WGA, while zeta potential was reduced by the addition of IPM and WGA. In vitro paclitaxel release profile was not affected by WGA but initial drug release was enhanced by adding IPM into the formulation. The WIT-NP showed a burst-release of about 32% of the paclitaxel load within the first 5 h followed by a slow zero-order release of another 7% of the drug load in the next 115 h. Compared with the clinical paclitaxel formulation, paclitaxel-loaded nanoparticles without IPM or WGA, or paclitaxel-loaded nanoparticles with only IPM or WGA, the WIT-NP had superior in vitro cytotoxicity against A549 and H1299 cells. IC50 for WIT-NP after 5 and 24 h incubation with A549 cells were not significantly different (15.5 and 15 μM, respectively) whereas the clinical formulation was not cytotoxic after 5 h but had IC50 of 14 μM after 24 h incubation. WIT-NP exhibited stronger cell-killing effect because of more efficient cellular uptake via WGA-receptor-mediated endocytosis and IPM-facilitated release of paclitaxel from the NPs. [Copyright &y& Elsevier]

Establishing the relationship between microstructures and mechanical properties of metallic glasses (MGs) is of great significance for guiding its application. Therefore, four groups of Mg 65 Cu 25 Y 10 MGs with the same size were obtained by rapid solidification at four pressures by molecular dynamics (MD) simulation in this paper, and uniaxial compression were performed. The results show that the volumes of shear transformation zones (STZ) of four models increase sequentially. The average atomic potential energy increases, and the plasticity increases. The smaller the non-affine displacement (NAD), the higher Top-10 Topologically close-packed (TCP) and defective TCP clusters, which are the main structural units of MGs. Medium-range ordered (MRO) nanoclusters composed of their interconnections, are broken into small-sized nanoclusters during compression. Regions with large-sized MRO nanoclusters tend to be "stiffer", making these regions difficult for large-scale structural rearrangement and plastic flow. The deformation resistance of these regions is thus improved. Chain-like nanoclusters are easier broken during compression, and MRO nanoclusters linked with larger bond numbers can withstand greater strain for enhancing their plasticity. These findings have excellent theoretical guidance for promoting plasticity in MGs. ● The plasticity of MGs improves as the increases of STZ volume. ● Stress is released by the massive decrease of Top10T& D -TCP clusters. ● The MRO nanoclusters can resist large non-affine deformation. ● The MRO nanoclusters with higher bond numbers can withstand greater strain. [ABSTRACT FROM AUTHOR]

Background: As the Diagnostic and Statistical Manual of Mental Disorders fifth version (DSM-5) was published, the Kiddie-Schedule for Affective Disorders and Schizophrenia-Present and Lifetime version (K-SADS-PL) was modified to adapt the new version (K-SADS-PL DSM-5). We translated it to Chinese (K-SADS-PL-C DSM-5) and described its reliability and validity.Methods: A total of 154 groups of 6 to 18-year-old children and their guardians were included. Trained interviewers interviewed subjects using the K-SADS-PL-C DSM-5. Interrater reliability was assessed by audio recording. Parent-reported scales, like child behavior checklist (CBCL), the Chinese version of Swan-son Nolan and Pelham, version IV scale-parent form (SNAP-IV), social responsiveness scale (SRS-1), and children-reported scales like depression self-rating scale for children (DSRSC) and the screen for child anxiety related emotional disorders (SCARED) were used to examine the validity of depressive disorder, ADHD, ASD, and ODD.Results: The K-SADS-PL-C DSM-5 had fair to excellent interrater (0.537-1.000) and test-retest (0.468-0.885) reliability of affective disorder and neurodevelopment disorder. The convergent validity of affective disorder and neurodevelopment disorder was good, and their divergent validity was acceptable.Limitations: i) Clinical questionnaires were insensitive in classifying disorders and had limitations in derived diagnoses. ii) Samples only came from clinical environment, iii) covered limited disease species, and iv) were small.Conclusion: The K-SADS-PL-C DSM-5 can support reliable and valid diagnoses for children with affect, neurodevelopmental, and behavioral disorders in China. [ABSTRACT FROM AUTHOR]

Highlights: [•] The rapid solidification of liquid Mg70Zn30 has been investigated by MD simulation. [•] The atomic configurations have been deeply analyzed by several microscopic methods. [•] Geometry analysis is for the icosahedron and the IS cluster linked of two icosahedra. [•] The second peak splitting in PDF g(r) curve of Mg70Zn30 alloy has been confirmed. [•] The R 2/R 1 =1.69, R 3/R 1 =1.98 and R 4/R 1 =2.57, is mainly caused by IS clusters. [ABSTRACT FROM AUTHOR]

Highlights: [•] Atomic layer deposition growth of Pt nanocrystals on Al2O3 film is investigated. [•] Pure metallic Pt nanocrystals can be formed at the initial growth stage. [•] Large area high density Pt nanocrystals are utilized for nonvolatile memory. [•] The MOS capacitors exhibit obvious memory effects including good retention. [•] Fowler–Nordheim tunneling serves as the dominant tunneling mechanism. [Copyright &y& Elsevier]

Understanding the mechanism of the formation and evolution of shear band is important for improving and designing the mechanical properties of amorphous alloys. Molecular dynamics simulation study on the uniaxial compression of amorphous Ca 65 Mg 15 Zn 20 alloy was performed in this work. The hidden correlation between the microstructure and evolution of shear band was revealed by a tracing method based on our previously proposed largest standard cluster analysis method. Results indicated that the topologically close-packed clusters are intrinsic characteristic structures of metallic glasses that closely related with the deformation process. And the three stages of the deformation process were highlighted and reasonably explicated by the number of shear transformation zones (STZs), the size of the largest STZs, and the indexes based on the Top-10 largest standard clusters. Where the shear transformation occurs closely depends on the local atomic structure of the sample, the areas of lower order and looser compaction are more prone to shear transformation, which gradually nucleated and evolved into shear bands with increased strain. Interestingly, results also revealed that the generation and propagation of shear bands conduct to the rejuvenation of the atomic structure outside the shear bands of the amorphous sample during compression. These findings improve the understanding of the generation and propagation of shear bands, so as to provide guidance for designing of new amorphous materials with desired mechanical properties. • TCP is the intrinsic characteristic structure of MGs which clearly reflects the deformation mechanism. • Three stages evolution process was explored by the tracing method. • Where the STZs initially form depends on the degree of the local structure order. • Once the shear bands form and propagate, the skeleton regions rejuvenate. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To describe differences in the primary tumour and distribution of cervical lymphadenopathy for cases of nasopharyngeal carcinoma (NPC) and nasopharyngeal non-Hodgkin''s lymphoma (NPNHL) using magnetic resonance (MR) imaging. Materials and methods: MR images of patients with NPC (n =272) and NPNHL (n =118) were independently reviewed by two experienced radiologists. Results: NPC had a higher incidence of tumour invasion associated with the levator and tensor muscles of the velum palatine, the longus colli and medial pterygoid muscles, the base of the pterygoid process, the clivus, the base and greater wing of the sphenoid bone, the petrous apex, the foramen lacerum, the foramen ovale, the hypoglossal canal, and intracranial infiltration. In contrast, NPNHL had a higher incidence of tumour invasion associated with the hypopharynx, the palatine and lingual tonsils, as well as the ethmoid and maxillary sinuses. NPNHL also had a higher incidence of extensive and irregular bilateral lymphadenopathy, and lymphadenopathy in the parotid. Conclusions: NPC more often involved an unsymmetrical tumour with a propensity to invade both widely and deeply into muscle tissue, the fat space, the neural foramen, and the skull base bone. In contrast, NPNHL tended to be a symmetrical and diffuse tumour with a propensity to spread laterally through the fat space and along the mucosa to the tonsils of the oropharynx and hypopharynx. These differences facilitate a differentiation of these diseases using MR images, and enhance our understanding of the biological behavior of these malignant tumours of the nasopharynx. [Copyright &y& Elsevier]

Abstract: Objective: To summarize the CT and MRI features in a series of fifteen cases of Kimura''s disease. Materials and methods: The clinical data, CT and MRI findings of 15 patients with histologically proved Kimura''s disease were retrospectively reviewed. All imaging data were consensually evaluated by two radiologists to determine the lesion location, number, morphology, margin, signal intensity or CT density, lesion texture, contrast enhancement pattern and involvement of adjacent structures. Results: There were 14 male and 1 female, with peripheral blood eosinophilia in all 14 patients. 13 patients were presented with a painless mass. 13 patients had lesions located in the head and neck related to the major salivary glands. 1 patient had lesion in groin. Subcutaneous fat diffuse atrophy around the tumor site was found in 11 patients. 9 patients had solitary mass and 6 patients had multiple masses. Most masses were ill-defined, but no specific density or signal patterns were found. Most patients exhibited enlarged or obviously enhanced abnormal lymph nodes but without necrosis. Conclusion: The characteristic distribution, morphology with enlarged draining lymphadenopathy, combined with the clinical features and laboratory examination enables a confident preoperative diagnosis of Kimura''s disease. [Copyright &y& Elsevier]

To deeply understand the effects of pressure on microstructural evolutions and mechanical properties, a molecular dynamics simulation study has been performed under pressures of 0–50 GPa for liquid Ni 64 Zr 36 alloy during solidification process. Adopting several microstructural analyzing methods, especially the cluster-type index method (CTIM-3) to analyze the local microstructures in the system, it is found that the icosahedral cluster (12 0 12 0 0 0 0 0 0) and the defect icosahedral cluster (12 0 8 0 0 0 2 2 0), (12 2 8 2 0 0 0 0 0) play a key role during the microstructural transitions. All the solidified structures are of amorphous structures consisted of various basic clusters and their combinations with different sizes. It is worth noting that all the glass transition temperature T g , main bond-types, main basic clusters and elastic constants are almost increased linearly with the increase of pressure. Especially, the amorphous structure formed under 50 GPa would possess the admirable microstructural configuration and excellent mechanical properties of materials. [ABSTRACT FROM AUTHOR]

Objectives The purpose of this study was to investigate the prognostic impact of tumor volume (TV) on patients with stage I non-small cell lung cancer (NSCLC) after complete resection. Materials and Methods We retrospectively reviewed the clinicopathological characteristics of 274 patients with stage I NSCLC who had received preoperative chest computed tomography (CT) scans and complete resection. TV was semi-automatically measured from chest CT scans by using an imaging software program. The optimal cutoff values of TV were determined by X-tile software. Disease-free survival (DFS) and overall survival (OS) were compared using Kaplan-Meier analysis. Univariate and multivariate analyses were performed to identify risk factors for DFS and OS. Results By using 3.046 cm 3 and 8.078 cm 3 as two optimal cutoff values of TV, the patients were separated into three groups. The 5-year DFS and OS for patients with TV ≤ 3.046 cm 3 , 3.046–8.078 cm 3 , and > 8.078 cm 3 were 88.0%, 73.6%, and 62.1%, respectively ( P < 0.001), and 91.4%, 84.5%, and 73.3%, respectively (p < 0.001). Multivariate analysis showed that age and TV were independent factors associated with DFS. Sex, age, histology, visceral pleural invasion, and TV were independent factors associated with OS. Stage Ia patients might be separated into three groups on the basis of TV with significantly different DFS and OS. Patients with tumor diameter ≤ 2 cm and 2–3 cm were also stratified into two groups with significantly different DFS and OS on the basis of TV, respectively. Conclusion TV is an independent risk factor for DFS and OS for stage I NSCLC after complete resection. TV might provide additional prognostic information over tumor diameter in patients with stage I NSCLC. [ABSTRACT FROM AUTHOR]

Background It has been reported that carnosic acid (CA) exhibits a range of biological activities including hepatoprotective, antioxidant and anti-inflammatory. However, the effect of carnosic acid in neuropathic pain remained elusive. Methods A neuropathic pain model of chronic constriction injury (CCI) was established in adult male Sprague–Dawley rats. Mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were recorded, and western blot was performed to detect sirtuin1 and p66shc content. Results Intrathecal administration of carnosic acid attenuated mechanical allodynia and thermal hyperalgesia in rats following chronic constriction injury. Interestingly, carnosic acid analgesic effect was positively associated with spinal sirtuin1 activation; however, p66shc was inhibited by carnosic acid in the spinal cord. In additional, sirtuin1 inhibitor EX-527 reversed the anti-nociceptive effect of carnosic acid. Conclusions Carnosic acid is effective in the treatment of the established CCI-induced pain. It may be possible that spinal sirtuin1 activition by carnosic acid attenuates neuropathic pain through a mechanism involving the down-regulation of p66shc expression. [ABSTRACT FROM AUTHOR]

Highlights: [•] An elaborate on-lattice alignment of Si diamond structure represents as the framework of simulation. [•] A systematic 3D Kinetic Monte Carlo model of GLAD-grown Si spirals on the nanosphere-array substrate has been built. [•] A characteristic length (i.e., the pitch) is proposed to indicate the spiral growth during substrate rotation. [•] The critical rotational speed of translation from spirals to upright columns has been predicted. [•] The competition mechanism between the lateral growth and the vertical growth dominates the structure geometry. [ABSTRACT FROM AUTHOR]

Highlights: [•] LiNi0.5Co0.2Mn0.3O2 powders were prepared by a modified sol–gel method. [•] Influence of anneal temperature on the physical and electrochemical properties of the samples was investigated. [•] LiNi0.5Co0.2Mn0.3O2 synthesized at 800°C exhibits the highest I (003)/I (104) and the lowest (I (006)+I (102))/I (101). [•] Excellent electrochemical performance is attributed to the low cation mixing and well hexagonal ordering. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: This study was focused on the serial changes in magnetic resonance images (MRI) of the skull-base bone that occur after endoscopic nasopharyngectomy in patients with local recurrent nasopharyngeal carcinoma (rNPC). Materials and methods: Nine patients with histologically proven rNPC were enrolled in this study. Two experienced radiologists independently reviewed all presurgical and postsurgical MR images for each patient. Results: At 36 sites on the skull base, the MRI signal underwent a change after surgery, which took the form of a heterogeneous pattern of hypointense regions with moderate contrast enhancement on T1WI. The onset of changes ranged between 2 weeks and 3 months after surgery. For 21 of the sites, the changes subsided over the course of follow-up, while in 6 they remained stable. At 9 sites, the alteration MRI signal became more pronounced with time. Changes were more common on the homolateral side of the skull base with respect to the recurrent tumor (P <0.05). The skull-base bone adjacent to the resection boundary had a higher incidence of signal change than nonadjacent areas (P <0.05). Conclusions: MRI changes in the skull base bone, having a number of distinguishing characteristics, appear to be a common sequel to endoscopic nasopharyngectomy for rNPC. [Copyright &y& Elsevier]

Abstract: Purpose: To investigate the correlation between the alterations of single-voxel 1H MRS and the histopathological characteristics of radiation brain injury following radiation. Materials and methods: Twenty-seven rabbits were randomized into nine groups to receive radiation with a single dose of 25Gy. The observation time points included a pre-radiation and 1, 2, 3, 4, 5, 6, 7, and 8wk following radiation. Each treatment group underwent conventional MRI and single-voxel 1H MRS, N-acetyl aspartate (NAA), choline (Cho), and creatine (Cr) were observed over the region of interest, and the presence or absence of lactate (Lac) and lipid (Lip) was detected. Histological specimens of each group were obtained after image acquisition. Results: The values of Cho were significantly increased in the first 3wk, and decreased over the following 5wk after radiation. Levels of NAA showed a trend toward a decrease 5wk after radiation. The levels of Cr were not changed between before and after radiation. The Cho/NAA metabolic ratio was significantly increased in weeks 6, 7, and 8 following irradiation, compared to pre-radiation values. Vascular and glial injury appeared on 2wk after RT in the histology samples, until 4wk after RT, necrosis of the oligodendrocytes, neuronal degeneration and demyelination could be observed. Conclusions: MRS is sensitive to detect metabolic changes following radiation, and can be used in the early diagnosis of radiation brain injury. [Copyright &y& Elsevier]