Quantifying Magnetic Moments And Susceptibilities Of Small Cylindrical And Spherical Objects In Mri

Purpose: The purpose of this PhD work is to develop a method for accurately quantifying effective magnetic moments and susceptibility of either cylindrical or spherical-like small objects from magnetic resonance imaging (MRI). A standard 3D gradient echo sequence with only one echo time is intended for our approach to measure the effective magnetic moment of a given object of interest. For the quantification of the susceptibility in the cylindrical objects at different orientations, a standard 3D gradient echo sequence with only one or two echo times is needed. Methods: Our method is to sum over complex MR signals around the object and equates those sums to equations derived from the magnetostatic theory. With those equations, our method is able to determine the center of the object with subpixel precision. By rewriting those equations, the effective magnetic moment or susceptibility of the object becomes the only unknown to be solved. The uncertainty of quantified effective magnetic moment and susceptibility of the object is derived from the error propagation method. For the object without having signal, if it is also imaged in the spin echo sequence, the volume of the object can be measured from spin echo images, the susceptibility difference between the object and its surrounding can be further quantified from the effective magnetic moment. If the cylindrical object has signal such as veins, the susceptibility of this object can be quantified by rearranging the equation with the known effective magnetic moment and the spin density surrounding the object. Numerical simulations, a variety of air straw, glass beads, and the gadolinium doped straw in phantom studies with different MR imaging parameters from a 1.5T and 3.0T machines have been conducted to test the robustness of this method. This method also quantified the magnetic moments and susceptibility of cerebral veins in human images from a 3.0T and 4.0T machines. Results: Quantified effective magnetic moments and susceptibility differences from different imaging parameters and methods all agree with each other within two standard deviations of estimated uncertainties. Conclusion: CISSCO method is developed to accurately quantify the effective magnetic moment and susceptibility of a given small object of interest. Most results are accurate within 10% of true values and roughly half of the total results are accurate within 5% of true values using very reasonable imaging parameters. Our method is minimally affected by the partial volume, dephasing, and phase aliasing effects

Pharmacological effects of Radix Angelica Sinensis (Danggui) on cerebral infarction

Radix Angelica Sinensis, the dried root of Angelica sinensis (Danggui), is a herb used in Chinese medicine to enrich blood, promote blood circulation and modulate the immune system. It is also used to treat chronic constipation of the elderly and debilitated as well as menstrual disorders. Research has demonstrated that Danggui and its active ingredients, as anti-arthrosclerotic, anti-hypertensive, antioxidant anti-inflammatory agents which would limit platelet aggregation, are effective in reducing the size of cerebral infarction and improving neurological deficit scores

Assessing the Stroke-Specific Quality of Life for Outcome Measurement in Stroke Rehabilitation: Minimal Detectable Change and Clinically Important Difference

<p>Abstract</p> <p>Background</p> <p>This study was conducted to establish the minimal detectable change (MDC) and clinically important differences (CIDs) of the physical category of the Stroke-Specific Quality of Life Scale in patients with stroke.</p> <p>Methods</p> <p>MDC and CIDs scores were calculated from the data of 74 participants enrolled in randomized controlled trials investigating the effects of two rehabilitation programs in patients with stroke. These participants received treatments for 3 weeks and underwent clinical assessment before and after treatment. To obtain test-retest reliability for calculating MDC, another 25 patients with chronic stroke were recruited. The MDC was calculated from the standard error of measurement (SEM) to indicate a real change with 95% confidence for individual patients (MDC₉₅). Distribution-based and anchor-based methods were adopted to triangulate the ranges of minimal CIDs. The percentage of scale width was calculated by dividing the MDC and CIDs by the total score range of each physical category. The percentage of patients exceeding MDC₉₅and minimal CIDs was also reported.</p> <p>Results</p> <p>The MDC₉₅of the mobility, self-care, and upper extremity (UE) function subscales were 5.9, 4.0, and 5.3 respectively. The minimal CID ranges for these 3 subscales were 1.5 to 2.4, 1.2 to 1.9, and 1.2 to 1.8. The percentage of patients exceeding MDC₉₅and minimal CIDs of the mobility, self-care, and UE function subscales were 9.5% to 28.4%, 6.8% to 28.4%, and 12.2% to 33.8%, respectively.</p> <p>Conclusions</p> <p>The change score of an individual patient has to reach 5.9, 4.0, and 5.3 on the 3 subscales to indicate a true change. The mean change scores of a group of patients with stroke on these subscales should reach the lower bound of CID ranges of 1.5 (6.3% scale width), 1.2 (6.0% scale width), and 1.2 (6.0% scale width) to be regarded as clinically important change. This information may facilitate interpretations of patient-reported outcomes after stroke rehabilitation. Future research is warranted to validate these findings.</p

How the Design Leadership and Strategic Design Drive New Value in Enterprises and Organizations

Today's design has shifted from the original primary pursuit of appearance and function to processes and systems, creating new meanings for corporate strategies, products and services. Nowadays, enterprises are increasingly paying attention to the power of design, and regard design as the main innovation method and incorporate it into the organizations. Design began to be considered a key role at the top of large organizations. Although people recognize that design can bring good effects to enterprises and organizations, and there is growing interest in cultivating design thinking, what are the leaders who can lead enterprises, organizations and have design thinking? Their characteristics and how to formulate and plan strategic design still not fully elucidated. Therefore, this research uses related theories to understand the way of thinking and characteristics of design leaders, only in this way we formulate good strategic design for enterprises and organizations, and become an indispensable and important help in today rapidly changing world

Oromotor variability in children with mild spastic cerebral palsy: a kinematic study of speech motor control

<p>Abstract</p> <p>Background</p> <p>Treating motor speech dysfunction in children with CP requires an understanding of the mechanism underlying speech motor control. However, there is a lack of literature in quantitative measures of motor control, which may potentially characterize the nature of the speech impairments in these children. This study investigated speech motor control in children with cerebral palsy (CP) using kinematic analysis.</p> <p>Methods</p> <p>We collected 10 children with mild spastic CP, aged 4.8 to 7.5 years, and 10 age-matched children with typical development (TD) from rehabilitation department at a tertiary hospital. All children underwent analysis of percentage of consonants correct (PCC) and kinematic analysis of speech tasks: poly-syllable (PS) and mono-syllable (MS) tasks using the Vicon Motion 370 system integrated with a digital camcorder. Kinematic parameters included spatiotemporal indexes (STIs), and average values and coefficients of variation (CVs) of utterance duration, peak oral opening displacement and velocity. An ANOVA was conducted to determine whether PCC and kinematic data significantly differed between groups.</p> <p>Results</p> <p>CP group had relatively lower PCCs (80.0-99.0%) than TD group (<it>p </it>= 0.039). CP group had higher STIs in PS speech tasks, but not in MS tasks, than TD group did (<it>p </it>= 0.001). The CVs of utterance duration for MS and PS tasks of children with CP were at least three times as large as those of TD children (<it>p </it>< 0.01). However, average values of utterance duration, peak oral opening displacement and velocity and CVs of other kinematic data for both tasks did not significantly differ between two groups.</p> <p>Conclusion</p> <p>High STI values and high variability on utterance durations in children with CP reflect deficits in relative spatial and/or especially temporal control for speech in the CP participants compared to the TD participants. Children with mild spastic CP may have more difficulty in processing increased articulatory demands and resulted in greater oromotor variability than normal children. The kinematic data such as STIs can be used as indices for detection of speech motor control impairments in children with mild CP and assessment of the effectiveness in the treatment.</p

Effects of Childhood Adversity and Resilience on Taiwanese Youth Health Behaviors

Adverse childhood experiences (ACEs) can leave negative impacts on one\u27s health behaviors or social functioning later in life. Resilient characteristics have been shown to mitigate effects against risk behaviors in developing adolescents. However, clinical and research attention has rarely been given to jointly consider the effects of ACEs and resilient characteristics on health behaviors in Taiwanese youth. Method: A total of 200 individuals aged 15–22 years were recruited from primary care settings, communities, and schools. Participants completed questionnaires assessing their ACEs, resilient characteristics, and health behaviors. Univariate analysis was firstly used to describe the correlates of ACEs and resilient characteristics. Further multivariate logistic regression analysis was used to examine the association of both factors with health behaviors. Results: More than half (61.5%) of those surveyed had been exposed to at least one category of ACE. Verbal (37%) and physical (21%) abuses were the most common types of ACEs. The counts in the ACE categories were associated with being involved in physical fights (odds ratio 1.28 [confidence interval 1.01–1.63]), property damage (1.29 [1.03–1.61]), running away from home (1.30 [1.05–1.60]), bullying victimization (1.37 [1.16–1.61]), and sleep problems/tiredness (1.25 [1.03–1.52]). Meanwhile, resilience scores were associated with decreased odds of infrequent seatbelt use (0.47 [0.23–0.97]), low fruit and vegetable intake (0.42 [0.21–0.86]) unsatisfied body image (0.46 [0.22–0.97]), and sleep problems/tiredness (0.37 [0.18–0.79]). Conclusions: ACEs and resilience characteristics play a significant role in shaping youth health behaviors. Further research should be undertaken to identify ways to build resilience against health risks in youth with prior ACE exposure

Paeonol Protects Memory after Ischemic Stroke via Inhibiting β-Secretase and Apoptosis

Poststroke dementia commonly occurs following stroke, with its pathogenesis related to β-amyloid production and apoptosis. The present study evaluate the effects of paeonol, one of the phenolic phytochemicals isolated from the Chinese herb Paeonia suffruticosa Andrews (MC), on protection from memory loss after ischemic stroke in the subacute stage. Rats were subjected to transient middle cerebral artery occlusion (tMCAo) with 10 min of ischemia. The data revealed that paeonol recovered the step-through latency in the retrieval test seven days after tMCAo, but did not improve the neurological deficit induced by tMCAo. Levels of Amyloid precursor protein (APP)- and beta-site APP cleaving enzyme (BACE; β-secretase)-immunoreactive cells, and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL)-positive cells decreased in the paeonol-administered group. Western blotting revealed decreased levels of Bax protein in mitochondria and apoptosis-inducing factor (AIF) in cytosol following paeonol treatment. In conclusion, we speculate that paeonol protected memory after ischemic stroke via reducing APP, BACE, and apoptosis. Supression the level of Bax and blocking the release of AIF into cytosol might participate in the anti-apoptosis provided by paeonol

Psychological Pathway from Obesity-Related Stigma to Anxiety via Internalized Stigma and Self-Esteem among Adolescents in Taiwan

The objective of this research was to examine the pathway from public stigma, to perceived stigma, to depression in adolescents via internalized stigma. Adolescents in grade 7 through 9 from a junior high school in Changhua County in Taiwan completed self-administered surveys from March to July in 2018. Adolescents were asked questions regarding depressive symptoms, obesity-related perceived stigma, and internalized stigma. Structural equation modeling was used to fit the pathway model. The pathway was first analyzed with the full sample and then stratified by actual and perceived weight status. Our final analytic sample consisted of 464 adolescents. The pathway model suggested an acceptable model fit. Perceived weight stigma (PWS) was significantly associated with internalized stigma regardless of actual or self-perceived weight status. Internalized stigma was significantly associated with anxiety for both actual (β = 0.186) and self-perceived nonoverweight (non-OW) participants (β = 0.170) but not for overweight (OW) participants (neither actual nor self-perceived). For OW adolescents, perceived weight stigma was associated with anxiety. However, the internalization process did not exist. It may be that the influence of perceived weight stigma is larger than internalized stigma on anxiety. It may also be that the level of internalization was not yet high enough to result in anxiet

Hot Cracking Susceptibility of 800H and 825 Nickel-Base Superalloys during Welding via Spot Varestraint Test

Hot cracking susceptibility of fillers 52 and 82 in 800H and 825 nickel-base superalloys was discussed using the Spot Varestraint test. The fillers of 52 and 82 were added into nickel-base superalloys via a gas tungsten arc welding (GTAW).Experimental results showed that the hot cracking sensitivity of the nickel-base superalloys with filler at high temperature was lower than that without filler. The hot cracking sensitivity had a slight effect when the filler 82 was added. The total length of crack was increased, the liquid-solid (L-S) two-phase range is higher so that the hot cracking susceptibility will be raised. The morphologies of cracks included the intergranular crack in the molten pool, molten pool of solidification cracking, heat-affected zone of intergranular cracks, and transgranular crack in the heat-affected zone

Neuroprotective Effect of Paeonol Mediates Anti-Inflammation via Suppressing Toll-Like Receptor 2 and Toll-Like Receptor 4 Signaling Pathways in Cerebral Ischemia-Reperfusion Injured Rats

Paeonol is a phenolic compound derived from Paeonia suffruticosa Andrews (MC) and P. lactiflora Pall (PL). Paeonol can reduce cerebral infarction volume and improve neurological deficits through antioxidative and anti-inflammatory effects. However, the anti-inflammatory pathway of paeonol remains unclear. This study investigated the relationship between anti-inflammatory responses of paeonol and signaling pathways of TLR2 and TLR4 in cerebral infarct. We established the cerebral ischemia-reperfusion model in Sprague Dawley rats by occluding right middle cerebral artery for 60 min, followed by reperfusion for 24 h. The neurological deficit score was examined, and the brains of the rats were removed for cerebral infarction volume and immunohistochemistry (IHC) analysis. The infarction volume and neurological deficits were lower in the paeonol group (pretreatment with paeonol; 20 mg/kg i.p.) than in the control group (without paeonol treatment). The IHC analysis revealed that the number of TLR2-, TLR4-, Iba1-, NF-κB- (P50-), and IL-1β-immunoreactive cells and TUNEL-positive cells was significantly lower in the paeonol group; however, the number of TNF-α-immunoreactive cells did not differ between the paeonol and control groups. The paeonol reveals some neuroprotective effects in the model of ischemia, which could be due to the reduction of many proinflammatory receptors/mediators, although the mechanisms are not clear