Strain and Bond Length Dynamics upon Growth and Transfer of Graphene by NEXAFS Spectroscopy from First-Principles and Experiment.

As the quest toward novel materials proceeds, improved characterization technologies are needed. In particular, the atomic thickness in graphene and other 2D materials renders some conventional technologies obsolete. Characterization technologies at wafer level are needed with enough sensitivity to detect strain in order to inform fabrication. In this work, NEXAFS spectroscopy was combined with simulations to predict lattice parameters of graphene grown on copper and further transferred to a variety of substrates. The strains associated with the predicted lattice parameters are in agreement with experimental findings. The approach presented here holds promise to effectively measure strain in graphene and other 2D systems at wafer levels to inform manufacturing environments.

Novel approaches for the promotion of physical activity and exercise for prevention and management of type 2 diabetes.

Despite increased evidence for the importance of lifestyle modification, physical activity and diet in diabetes prevention and management, habitual physical activity levels have declined in recent decades in China and India. Further, other risk factors for type 2 diabetes, including overweight, obesity and physical inactivity, have also worsened. Here we present evidence for the importance of physical activity and exercise in the amelioration of type 2 diabetes and propose a novel approach to address the challenge of improving lifestyle behaviors in China and India-Movement is Medicine and a P4 (predictive, preventive, personalized and participatory) approach.

The potential of low-intensity and online interventions for depression in low- and middle-income countries.

The World Health Organization (WHO) reports that low- and middle-income countries (LMICs) are confronted with a serious 'mental health gap', indicating an enormous disparity between the number of individuals in need of mental health care and the availability of professionals to provide such care (WHO in 2010). Traditional forms of mental health services (i.e. face-to-face, individualised assessments and interventions) are therefore not feasible. We propose three strategies for addressing this mental health gap: delivery of evidence-based, low-intensity interventions by non-specialists, the use of transdiagnostic treatment protocols, and strategic deployment of technology to facilitate access and uptake. We urge researchers from all over the world to conduct feasibility studies and randomised controlled studies on the effect of low-intensity interventions and technology supported (e.g. online) interventions in LMICs, preferably using an active control condition as comparison, to ensure we disseminate effective treatments in LMICs.

Internet cognitive behavioural therapy for mixed anxiety and depression: a randomized controlled trial and evidence of effectiveness in primary care.

BACKGROUND: Major depressive disorder (MDD) and generalized anxiety disorder (GAD) have the highest co-morbidity rates within the internalizing disorders cluster, yet no Internet-based cognitive behavioural therapy (iCBT) programme exists for their combined treatment. METHOD: We designed a six-lesson therapist-assisted iCBT programme for mixed anxiety and depression. Study 1 was a randomized controlled trial (RCT) comparing the iCBT programme (n = 46) versus wait-list control (WLC; n = 53) for patients diagnosed by structured clinical interview with MDD, GAD or co-morbid GAD/MDD. Primary outcome measures were the Patient Health Questionnaire nine-item scale (depression), Generalized Anxiety Disorder seven-item scale (generalized anxiety), Kessler 10-item Psychological Distress scale (distress) and 12-item World Health Organization Disability Assessment Schedule II (disability). The iCBT group was followed up at 3 months post-treatment. In study 2, we investigated the adherence to, and efficacy of the same programme in a primary care setting, where patients (n = 136) completed the programme under the supervision of primary care clinicians. RESULTS: The RCT showed that the iCBT programme was more effective than WLC, with large within- and between-groups effect sizes found (>0.8). Adherence was also high (89%), and gains were maintained at 3-month follow-up. In study 2 in primary care, adherence to the iCBT programme was low (41%), yet effect sizes were large (>0.8). Of the non-completers, 30% experienced benefit. CONCLUSIONS: Together, the results show that iCBT is effective and adherence is high in research settings, but there is a problem of adherence when translated into the 'real world'. Future efforts need to be placed on developing improved adherence to iCBT in primary care settings.

The long-term benefits of a multi-component exercise intervention to balance and mobility in healthy older adults.

We examined the long-term effects of a multi-component exercise program on balance, mobility and exercise behavior. The benefits of a community-based resistance and flexibility exercise intervention in a group of healthy older (60-75 years) individuals were recorded 12 months after completion of the randomized control intervention. Differences between those participants who continued to exercise and those who discontinued were investigated. Significant improvements from baseline in sit to stand (p<0.001), timed up and go (p=0.001), and sway (p<0.001) remained at follow up in the exercise intervention group, with a control group unchanged. Participants who continued exercising had significantly greater improvements in strength immediately after the intervention, compared to those who discontinued (p=0.004). Those who continued regular resistance training performed better in the step test at 12-month follow up (p=0.009) and believed that the program was of more benefit to their physical activity (p<0.001) than those who discontinued exercising. Benefits to balance and mobility persist 1 year after participation in a multi-component exercise program, due in part to some continuing participation in resistance training. Motivation to continue resistance training may be related real and perceived benefits attained from the intervention as well as the environmental context of the intervention.

Evaluation of dysfunction following reconstruction of an anorectal anomaly.

To evaluate the utility of anorectal manometry (ARM) and magnetic resonance imaging (MRI) with an endocoil in the assessment of dysfunction in children with repaired anorectal anomalies (ARA), 15 patients aged 1 to 15 years with repaired ARAs and chronic faecal incontinence or constipation were prospectively recruited. They underwent clinical assessment using a modified Wingfield score (MWS). ARM and MRI with an endocoil and conventional external coil were carried out. The results of ARM alone, MRI alone, and a combination of ARM and MRI were correlated with the MWS. Manometric internal anal sphincter (IAS) scores determined from sphincter length and activity correlated with MWS (r = 0.56, P = 0.02); manometric scores of rectal peristaltic activity did not. Overall manometric score (IAS and rectal scores combined) showed a correlation with MWS (r = 0.55, P = 0.02). Endoanal MRI sphincter scores did not correlate with MWS, but the presence of a megarectum on MRI did (r = 0.44, P = 0.05). Overall MRI score did not correlate with MWS. Minor neurosacral anomalies were shown on MRI in 3 children who had poor functional scores. Combined manometric and MRI scores showed a correlation with MWS (r = 0.58, P = 0.01). ARM and MRI are potentially useful in the assessment of dysfunction of children with repaired ARAs. Both modalities require refinement and further assessment in the context of directing management.

Detection of pelvic lymph node metastases in gynecologic malignancy: a comparison of CT, MR imaging, and positron emission tomography.

OBJECTIVE: Accurate assessment of lymph node status before treatment is critical in the treatment of gynecologic cancers because the 5-year survival and treatment of women is influenced by lymph node involvement. The aims of this study were to investigate the ability of X-ray CT, MR imaging, and (18)F-FDG positron emission tomography (PET) to detect pelvic lymph node metastases by comparing imaging with histopathologic findings after lymph node dissection. MATERIALS AND METHODS: Eighteen patients with gynecologic cancers were studied by all three imaging methods before surgery. The images were initially reviewed with routine diagnostic conditions and then, subsequently, by two observers who were unaware of the clinical and histopathologic findings of the patients. The nodal sites were split into upper (aortic to common iliac bifurcations) and lower (common iliac bifurcations to inguinal ligament) iliac chains. All observers' results were statistically analyzed with specificity, sensitivity, positive and negative predictive values, Fisher's exact test (individual observers) or chi-square test (combined observers), and Cohen's kappa test. RESULTS: Eight of 18 patients had lymph node metastases at histology. Findings of all three modalities agreed in full in only one patient. CT correctly revealed 10 node-negative patients, whereas MR imaging was correct in eight of these patients. (18)F-FDG PET correctly depicted one patient with lymph nodes negative for tumor. CT was the most specific imaging modality (97.0%), with MR imaging and PET rendering values of 90.7% and 77.3%, respectively, but sensitivity of all modalities was low (CT, 48.1%; MR imaging, 53.7%; PET, 24.5%). Observer agreement for each modality was good; kappa values among all observers were 0.88 for CT, 0.85 for MR imaging, and 0.72 for PET. CONCLUSION: CT is the most specific modality for detecting lymph nodes positive for tumor in gynecologic cancers, whereas MR imaging is the most sensitive. The poor results of PET in the pelvis are attributed to urinary (18)F-FDG in the ureters or bladder, which may mask or imitate lymph node metastases.

Catheter tracking for MR fluoroscopy: design of a transmit/receive coil for use with a nasogastric tube.

A coil tuned to 21.3 MHz was incorporated into a nasogastric tube and used as a marker of tube position during magnetic resonance (MR) imaging in a 0.5-T scanner. Catheter tracking was investigated with the coil used in both transmit/receive and in receive-only modes. Data acquired from this coil were overlaid on images obtained using the body coil of the scanner. Visualization of the full length of the catheter with local high signal at the tip was achieved with a temporal resolution of approximately 1 second. J. Magn. Reson. Imaging 2001;13:127-130.

Psychometric concerns in neuropsychological testing.

This article describes measurement and norming problems with commonly used neuropsychological tests. Test standards regarding differential diagnoses, validity and reliability, the need for manuals, standardized administration, screening, and research versions are discussed. Further development of reliability, validity, sensitivity and specificity is needed for many tests.

Magnetic resonance imaging of the primary site in stage I cervical carcinoma: A comparison of endovaginal coil with external phased array coil techniques at 0.5T.

OBJECTIVE: To compare endovaginal with pelvic phased array coil magnetic resonance imaging (MRI) in detection of Stage I cervical carcinoma by correlating the findings with histopathology. PATIENTS AND METHODS: Forty consecutive patients with Stage I cervical carcinoma confirmed histologically were studied using an endovaginal coil alone immediately followed by a pelvic phased array coil. T1-W transverse and T2-W FSE sagittal images made with each coil were analyzed independently by two radiologists noting the presence and size of a mass within the cervix and any parametrial extension or involvement of adjacent organs. Tumor volumes were measured using the electronic calliper to compute tumor area on each slice and multiplying by the slice thickness. Thirty patients underwent radical hysterectomy, one a trachylectomy, one simple hysterectomy and four extended cone biopsies. Four patients had radiotherapy to the primary tumor. Following surgery, histopathologic findings were recorded and tumor volumes measured. RESULTS: Tumor volumes ranged from 0-106 cm(3)(median 1.4 cm(3), mean 9 +/- 19.4 cm(3)). Thirty-six patients had correlation of the primary site with the surgical specimen. Agreement between observers was excellent for both endovaginal (k = 0.90) and pelvic phased array (k = 0.96) techniques. Combined sensitivity and specificity for both observers of endovaginal MR imaging for detection of tumor was 96% and 70%, respectively; for pelvic phased array imaging sensitivity was substantially less at 54%. Specificity was higher at 83.7%, probably because small abnormalities were seldom visible. In patients treated surgically, early parametrial involvement in four women on endovaginal MRI was confirmed histologically in two. Pelvic phased array imaging showed early parametrial involvement in four women and was confirmed in one. CONCLUSION: Endovaginal MRI adds substantially to information from pelvic phased array images in the preoperative assessment of patients with early cervical cancer. J. Magn. Reson. Imaging 2000;12:1020-1026.

Chronic myelogenous leukemia primitive hematopoietic progenitors demonstrate increased sensitivity to growth factor-induced proliferation and maturation.

We investigated whether primary chronic myelogenous leukemia (CML) hematopoietic progenitors demonstrated altered proliferation and maturation in response to growth factor (GF) stimulation. The effect of GF stimulation on proliferation and expansion of committed and primitive progenitors (colony forming cells [CFC]) was evaluated. Culture of CML and normal CD34(+) cells with different GF for 7 days resulted in similar expansion of committed progenitors (CFC). In contrast, GF culture conditions that expanded normal primitive progenitors (week-6 long-term culture-initiating cells (LTC-IC)] led to depletion of CML LTC-IC numbers. GF culture also resulted in increased depletion of week-10 extended LTC-IC, which represent an even more primitive progenitor population, from CML compared with normal CD34(+) cells. CML CD34(+) cells enter into cycle more quickly than normal CD34(+) cells and CML CFC expansion was accelerated compared to normal CFC. Evaluation of primitive progenitor proliferation using PKH-26 and single-cell LTC-IC analysis demonstrated that the majority of CML LTC-IC remaining after GF culture originated from divided CD34(+) cells, whereas GF-cultured normal LTC-IC were derived mainly from undivided cells. Depletion of CML primitive progenitor numbers in association with increased proliferation suggests increased sensitivity to GF-induced maturation. These studies indicate that CML primitive progenitors have enhanced sensitivity to GF-induced cell division and maturation. Altered GF responsiveness may contribute to abnormal expansion of malignant myeloid cells in CML. These findings may also be applied toward the development of novel approaches to select benign stem cells in CML.

Pre-polarized saline: an in vivo feasibility study of a potential contrast agent.

The potential for using pre-polarized liquids as contrast agents in vivo is investigated and the feasibility of the method demonstrated. In this study we show the enhancement obtained following intravenous delivery of pre-polarized saline into the antecubital vein of a volunteer. This form of contrast agent provides signal gain on time scales commensurate with its T(1) and allows repeated doses to be administered, thus making alternate acquisitions of data with and without enhancement practicable.

Transanal MR imaging after repair of anorectal anomalies in children: appearances in pull-through versus posterior sagittal reconstructions.

OBJECTIVE: Our objective was to use transanal MR imaging to compare the anatomic appearance of the components of the anal sphincter and the pattern of scarring after a pull-through perineoplasty versus a posterior sagittal anorectoplasty. SUBJECTS AND METHODS: Sixteen children ranging in age from 10 months to 15 years (mean, 10 years) were imaged using transanal receiver coils appropriate to the size of the child. Five had low, four intermediate, and seven high anomalies. Seven had undergone a transanal pull-through procedure, and nine had undergone posterior sagittal reconstruction. The integrity of the muscles was assessed on T1-weighted and short inversion time inversion recovery transverse and coronal images using a qualitative MR imaging score. The pattern of scarring was also assessed. RESULTS: In the transanal pull-through group, four of seven patients showed external sphincter deficiency. A circumferential low-signal-intensity band was seen inferior to the sphincter in six patients. All posterior sagittal reconstructions had a long posterior midline scar. Five of nine patients showed external sphincter deficiency, whereas a further two had internal sphincter deficiency. No differences were seen in MR imaging scores for each operative procedure for all grades of severity of anorectal anomaly. However, a comparison between high and intermediate anomalies showed a small improvement in MR imaging score using the transanal pull-through procedure (Mann-Whitney U test = 3, p < .03). Manometric pressures obtained in 13 patients were poor. CONCLUSION: Transanal MR imaging identifies focal defects and patterns of scarring of the anal sphincter complex in infants and children and provides valuable information about individual muscle components.

Effect of 3 weeks of detraining on the resting metabolic rate and body composition of trained males.

OBJECTIVE: To examine the hypothesis that detraining decreases the resting metabolic rate (RMR) of long-term exercisers. DESIGN: Eight pairs of subjects were matched for age, mass and training volume. They were then randomly allocated to either a control group (continue normal training) or detraining group (stop normal training but continue activities of daily living). SETTING: Exercise Physiology Laboratory, The Flinders University of South Australia. SUBJECTS: Sixteen male subjects (age 23.1 +/- 4.7 y (s.d.); mass 73.73 +/- 8.9 kg; VO2max 60.2 +/- 6.3 ml. kg-1.min-1; height 180.3 +/- 5.0 cm; body fat 14.6 +/- 5.4%) were selected from a pool of respondents to our advertisements. INTERVENTIONS: Each pair of subjects was measured before and after a 3-week experimental period. RESULTS: Two (groups) x 3 (2-, 3-and 4-compartment body composition models) ANOVAs were conducted on the difference between the pre- and post-treatment scores for percentage body fat, fat-free mass (FFM) and relative RMR (kJ.kg FFM-1.h-1). No significant between-group differences were identified except for the detraining group's small decrease in FFM (0.7 kg, P = 0.05). The main effects for body composition model were all significant; but the overall differences between the multicompartment models and the 2-compartment one were less than their technical errors of measurement. No significant interaction (P = 0.51) resulted from a 2 x 2 ANOVA on the pre- and post-treatment absolute RMR data for the control (315.2 and 311.9 kJ/h) and detraining groups (325.4 and 325.5 kJ/h). CONCLUSIONS: 3-weeks detraining is not associated with a decrease in RMR (kJ/h, kJ.kg FFM-1.h-1) in trained males; hence, our data do not support a potentiation of the RMR via exercise training. The greater sensitivity of the multicompartment models to detect changes in body composition was of marginal value.

High-resolution magnetic resonance imaging of the anal sphincter using a dedicated endoanal receiver coil.

The use of a surface coil in MR imaging improves signal-to-noise ratio of adjacent tissues of interest. We therefore devised an endoanal receiver coil for imaging the anal sphincter. The probe is solid and re-usable: it comprises a saddle geometry receiver with integral tuning, matching and decoupling. It is placed in the anal canal and immobilised externally. Both in vitro and in vivo normal anatomy is identified. The mucosa is high signal intensity, the submucosa low signal intensity, the internal sphincter uniformly high signal intensity and the external sphincter low signal intensity on T1- and T2-weighted images. In females, the transverse perineal muscle bridges the inferior part of the external sphincter anteriorly. In perianal sepsis, collections and the site of the endoanal opening are identified. In early-onset fecal incontinence following obstetric trauma/surgery, focal sphincter defects are demonstrated; in late-onset fecal incontinence external sphincter atrophy is seen. In fecally incontinent patients with scleroderma, forward deviation of the anterior sphincter musculature with descent of rectal air and feces into the anal canal is noted. The extent of sphincter invasion is assessed in low rectal tumours. In children with congenital anorectal anomalies, abnormalities of the muscle components are defined using smaller-diameter coils. Such information is invaluable in the assessment and surgical planning of patients with a variety of anorectal pathologies.

Design and use of internal receiver coils for magnetic resonance imaging.

This review describes coils for MRI that are inserted into the body through natural orifices. It covers the design and implementation of small internal receiver coils for use in the pelvis and gastrointestinal tract. Normal anatomy delineated by the high resolution obtained by using these coils and the appearances in a number of disease states for each clinical application are described.

Fecal incontinence in scleroderma: assessment of the anal sphincter with thin-section endoanal MR imaging.

PURPOSE: To compare the magnetic resonance (MR) imaging appearance of the anal sphincter in patients with fecal incontinence and scleroderma with that in patients with fecal incontinence alone, scleroderma alone, or neither. MATERIALS AND METHODS: The study population comprised 14 patients with fecal incontinence and scleroderma, four with scleroderma alone, 13 with incontinence alone, and six with neither. T1- and T2-weighted spin-echo, magnetization transfer contrast-weighted, and dynamic gadolinium-enhanced images were obtained and analyzed for the integrity, thickness, and length of sphincter components. Magnetization transfer contrast ratios and T2 were calculated to assess fibrosis of the internal sphincter. The percentage enhancement above baseline was calculated at 30-second intervals for the internal and the external sphincter. RESULTS: Eleven patients with incontinence and scleroderma showed descent of rectal air and feces into the anterior anal canal, with forward deviation of the significantly (P < .05) atrophied internal sphincter, which showed a slower gadolinium-enhancement pattern compared with that in other groups. Patients with incontinence alone showed no evidence of internal sphincter deviation or altered vascularity but had a significant reduction (P < .05) in deep external sphincter bulk. CONCLUSION: In patients with fecal incontinence and scleroderma, endoanal MR imaging helps delineate the anterior sphincter deformity and shows the slower gadolinium-enhancement pattern on dynamic studies of the internal sphincter.

Platinum coil-mediated implantation of growth factor-secreting endovascular tissue grafts: an in vivo study.

PURPOSE: To demonstrate in vivo that platinum embolic coils can be used to deliver genetically modified, growth factor-secreting fibroblast grafts into the endovascular space with the long-term goal of improving fibrosis within coil-embolized cerebral aneurysms. MATERIALS AND METHODS: Murine fibroblasts that contained multiple inserts of the DNA for human basic fibroblast growth factor were grown in culture onto 10-mm-long segments of Guglielmi detachable coils. Control (n = 4) and fibroblast-bearing (n = 4) coils were implanted into the common carotid artery in nude rats. The arterial segments that contained the coil were harvested after 14 or 35 days. Cellular content and collagen formation in the treated vessels were assessed histologically. RESULTS: At both 14 and 35 days, samples with control coils showed primarily involuting blood elements with minimal fibroblast proliferation or collagen formation. At 14 days, samples with fibroblast-bearing coils showed extensive fibroblast proliferation. At 35 days, samples with fibroblast-bearing coils showed marked interval fibroblast proliferation and collagen formation. CONCLUSION: Platinum coils can be used as a cell delivery device. Direct intravascular implantation of growth factor-secreting fibroblast grafts leads to improved intravascular scar formation, therefore theoretically reducing the potential for aneurysm regrowth or coil compaction.

Impulse response of a dental implant in bone by numerical analysis.

The osseointegration process of titanium dental implants in bone has been simulated previously using natural frequency and impulse excitation. However, the impulse strength was arbitrarily chosen and may not have yielded the correct frequencies and displacements to be compared with those measured in a clinical situation. In this work the range of impulse excitation strengths applied to a dental implant osseointegrated in bone and the corresponding response have been examined using the finite element method. Both conditions of a dental pin only and a dental pin with attached cantilever integrated in the mandible have been examined. The dynamic analysis indicated that the frequency and displacement responses are indeed sensitive to impulse duration and direction but independent of impulse load. The analysis summarizes the proper impulse excitation values for a correct interpretation of clinically measured frequency response data.

Apparent life-threatening events in presumed healthy neonates during the first three days of life.

OBJECTIVE: To study the historical, clinical and pneumographic correlates of apparent life-threatening events (ALTEs) in a term newborn nursery population during the first 3 days of life in a maternity hospital. METHODS: Twenty newborns with ALTEs during the first 3 days of life were studied. Family, antenatal, and intrapartum histories were reviewed. Diagnostic and therapeutic data surrounding the ALTEs were documented. Multichannel recordings performed after the ALTEs occurred were analyzed. Hospital discharge dispositions and postdischarge outcomes were reviewed. RESULTS: Of approximately 15 000 deliveries during a three-year period, 20 infants had ALTEs. Apnea was the most common presenting symptom, and cyanosis usually accompanied the event. Tactile stimulation and oxygen were the most frequent acute treatments, with airway clearance, intermittent positive pressure ventilation, and cardiac massage less common. Forty percent of the events had potentially identifiable causes, including central nervous system abnormality, airway obstruction, or a persistent fetal cardiovascular shunt. Of the initial nultichannel recordings, 11 had desaturation oor less the 85%, 10 had apneic pauses of greater than 15 seconds, and 4 had bradycardia of less than 80 beats per minute. Eighteen infants were discharged and received home monitors; 4 received medication. ALTEs recurred in 4 infants before discharge and in 1 after discharge. No deaths occurred. CONCLUSIONS: (1) ALTEs do occur in the early newborn period in a low-risk term group; (2) causes are unknown in the majority of cases; (3) multichannel recordings may have abnormalities; and (4) the likelihood of recurrent ALTEs is greater during the first week than during the next 2 months.