Interfractional Geometric Variations and Dosimetric Benefits of Stereotactic MRI Guided Online Adaptive Radiotherapy (SMART) of Prostate Bed after Radical Prostatectomy: Post-Hoc Analysis of a Phase II Trial

Purpose: To evaluate geometric variations of patients receiving stereotactic body radiotherapy (SBRT) after radical prostatectomy and the dosimetric benefits of stereotactic MRI guided adaptive radiotherapy (SMART) to compensate for these variations. Materials/Methods: The CTV and OAR were contoured on 55 MRI setup scans of 11 patients treated with an MR-LINAC and enrolled in a phase II trial of post-prostatectomy SBRT. All patients followed institutional bladder and rectum preparation protocols and received five fractions of 6−6.8 Gy to the prostate bed. Interfractional changes in volume were calculated and shape deformation was quantified by the Dice similar coefficient (DSC). Changes in CTV-V95%, bladder and rectum maximum dose, V32.5Gy and V27.5Gy were predicted by recalculating the initial plan on daily MRI. SMART was retrospectively simulated if the predicted dose exceeded pre-set criteria. Results: The CTV volume and shape remained stable with a median volumetric change of 3.0% (IQR −3.0% to 11.5%) and DSC of 0.83 (IQR 0.79 to 0.88). Relatively large volumetric changes in bladder (median −24.5%, IQR −34.6% to 14.5%) and rectum (median 5.4%, IQR − 9.7% to 20.7%) were observed while shape changes were moderate (median DSC of 0.79 and 0.73, respectively). The median CTV-V95% was 98.4% (IQR 94.9% to 99.6%) for the predicted doses. However, SMART would have been deemed beneficial for 78.2% of the 55 fractions based on target undercoverage (16.4%), exceeding OAR constraints (50.9%), or both (10.9%). Simulated SMART improved the dosimetry and met dosimetric criteria in all fractions. Moderate correlations were observed between the CTV-V95% and target DSC (R2 = 0.73) and bladder mean dose versus volumetric changes (R2 = 0.61). Conclusions: Interfractional dosimetric variations resulting from anatomic deformation are commonly encountered with post-prostatectomy RT and can be mitigated with SMART.

Choice of Continuous Glucose Monitoring Systems May Affect Metrics: Clinically Relevant Differences in Times in Ranges

Background Continuous glucose monitoring-derived parameters are becoming increasingly important in the treatment of people with diabetes. The aim of this study was to assess whether these parameters, as calculated from different continuous glucose monitoring systems worn in parallel, are comparable. In addition, clinical relevance of differences was investigated. Methods A total of 24 subjects wore a FreeStyle Libre (A) and a Dexcom G5 (B) sensor in parallel for 7 days. Mean glucose, coefficient of variation, glucose management indicator and time spent in different glucose ranges were calculated for each system. Pairwise differences between the two different continuous glucose monitoring systems were computed for these metrics. Results On average, the two CGM systems indicated an identical time in range (67.9±10.2 vs. 67.9±11.5%) and a similar coefficient of variation; both categorized as unstable (38.1±5.9 vs. 36.0±4.8%). In contrast, the mean time spent below and above range, as well as the individual times spent below, in and above range differed substantially. System A indicated about twice the time spent below range than system B (7.7±7.2 vs. 3.8±2.7%, p=0.003). This could have led to different therapy recommendations in approximately half of the subjects. Discussion The differences in metrics found between the two continuous glucose monitoring systems may result in different therapy recommendations. In order to make adequate clinical decisions, measurement performance of CGM systems should be standardized and all available information, including the HbA1c, should be utilized.

The Effect of Downsizing, Merger & Acquisition, and Transformational Leadership on Company Performance

Do downsizing and merger & acquisition significantly and positively affect a company performance? Previous studies on the case showed contradictory results. The result of this research supports that downsizing and merger & acquisition do not positively and significantly affect company performance.Standardized regression weights coefficients on AMOS output for both variables of downsizing and merger & acquisition are -0.0787 and -0.0109, each. Thus, downsizing and merger & acquisition actually have negative impacts on company performance. Similar coefficient for the variable of transformational leadership is 0.7611; it has a positive and significant impact on company performance.Research’s respondents are 327 employees of PT Holcim Indonesia Tbk. Test of Cronbach’s Alpha gives 0.886 indicating that the research data is reliable. Some tests of the research model yield good fit for CMIN/df (1.41), RMSEA (0.04), RMR (0.04), AGFI (0.92), and CFI (0.98), as well as acceptable fit for GFI (0.94) and NFI (0.94).Transformational leadership needs to be applied continuously to improve company performance. Transformational leader shall not put downsizing and merger & acquisition from corporate agenda because they both have a negative impact on company performance.

FGM based on copper–alumina composites for brake disc applications

Copper–alumina composites of the interpenetrating networks type are interesting materials for many applications because of their properties. On the base of preliminary investigations and practical works, in order to obtain a material with high resistance to friction wear as well as good dissipation of heat generated during work, it was decided that a developed material would be prepared on the base of the Cu–Al2O3 composite, with a graded composition. In this paper, we present the developed method of manufacturing dense copper–alumina FGMs, using ceramic preform with a graded porosity infiltrated with molten copper. The article also presents the full characterization of the obtained materials and mainly the impact of microstructure on the useful properties. The produced gradient material of a Cu–Al2O3 brake disk underwent tribological tests under conditions resembling real conditions. These disks also went through a series of abrasive wear trials at different operation stages. In comparison with the reference material (i.e., grey cast iron), the obtained gradient materials are characterized by a lower degree of wear when retaining a similar coefficient of friction value due to the ceramic phase addition. Additionally, it was found that using the copper-based gradient material guarantees faster heat dissipation from the contact area.

DNA POLYMORPHISM AND GENETIC DIVERSITY OF MANGO (Mangifera sp.) GERMPLASM IN TROPICAL ISLAND

Creation of new superior varieties of mango through the empowerment of local genetic resources requires information about the potential properties of mango germplasm, including DNA polymorphism and its genetic diversity. This research aimed to obtain basic data on DNA polymorphism, genetic relationship, genetic similarity level, and molecular accession of Bali’s unique local mango. Sampling was conducted in four regencies in the Province of Bali. DNA preparation, PCR, and microsatellite analysis were carried out at the Laboratory of Genetics and Plant Breeding, Faculty of Agriculture, Gadjah Mada University. It found 44accessions of mangoes in Bali. The test results with 10 pairs of SSR markers showed that all primers produced polymorphic loci. There were 825 amplified DNA bands. Primer of AY31 produced the highest number of loci, which were 14 loci, while AY21 produced the fewest loci, i.e., 3 loci. Forty-four mango accessions showed a genetic similarity coefficient of 0.27 to 0.97. At a coefficient of 0.27, accessions were divided into 2 major groups: group A and group B. Group A consisted of two accessions, namely, KRA-005 and BDG-006 (Mangifera foetida Lour.), which had a similar coefficient of 0.657. Group B was divided into twosmaller groups, namely, groups B1 and B2, at a similarity coefficient of 0.342. Group B1 consisted of 39 accessions, while group B2 consisted of 3 accessions. Accessions Madu Anggur, Gading, Sambuk Mengwi, Kakul and Pakel Sulangai were identified as having unique alleles.

Relationships and comparative reliability of ultrasound derived measures of upper and lower limb muscle thickness, and estimates of muscle area from anthropometric measures

The gold standard measure for assessing muscular size currently is magnetic resonance imaging; however, it is expensive and not easily accessible. Both anthropometric techniques (AN) and ultrasound (UT) are commonly employed methods to measure muscle size. However, the degree to which these approaches offer similar information has not been examined. The aim of the study was to investigate the relationship between UT and AN measurements of muscle thickness in addition to their comparative reliability. Fifteen males (27±9 years) volunteered to take part in the study and underwent both AN and UT measures, taken to assess their upper arm and upper leg muscle size on separate days a week apart. Correlations between the two measures ranged from r=0.548-0.918 (p<0.05) suggesting a good relationship and thus comparable information. Results showed similar coefficient of variation (CV%) for the upper leg (AN 2.3%, UT 2.4%), but slightly greater reliability for UT results for the upper arm (AN 5.5%, UT 2.8%). It appears that both methods are reliable approaches to measurement of muscle size, though AN likely represents a lower cost and greater ease of use. Researchers should consider this when deciding upon which approach to use in the assessment of muscle size in the absence of gold standard approaches.

ISOLATING THE MONOKARYON COLLECTION OF Pleurotus spp.

Pleurotus spp. is one of the most important cultivated mushrooms in the world by their nutrition and medicinal property. In Vietnam, although many Pleurotus species are popularly cultivated, but most of them are imported. These strains are easily degenerated when they are cultivated in large scale, because they are difficult to adapt to the environment of Vietnam. This research aims to construct the monokaryon collection of Pleurotus spp. with details of taxonomy, genetic diversity, cultivating traits, monokaryotic mating types focused on Pleurotus strains with the high yield, genetic stable and adaptability to Vietnam environment. 09 Pleurotus strains were collected in South Vietnam and signed PL1 to PL9. Identification by morphology and phylogenetic analysis based on ITS sequences showed that PL1 is P. citrinopileatus; PL2, PL6 and PL9 are P. ostreatus; PL3 is P. cystidiosus; PL4 and PL8 are P. pulmonarius; PL5 is P. cornucopiae; PL7 is P. incarnatus. AFLP analyses indicated a wide genetic diversity of the collected strains with the similar coefficient 52 – 90 %. Pair of PL2 and PL9 is the most closed genetic distance and pair of PL6 and PL7 is the furthest genetic distance. PL4, PL8 and PL1 adapted well to Vietnam environment. PL2, PL5, PL6 and PL9 are cold strains and formed fruiting bodies slowly. PL3 had the highest biological efficiency, but the longest harvesting period (2.5 – 3 months). Except PL7, the biological efficiencies of other strains are over 50 %. 120 monokaryotic isolates of PL1, PL2 and PL8 are collected and determined the mating type.

Proposed Solution to the Problem of Thermal Stress Induced Failures in Medical Electronic Systems

The concept of miniaturization has propagated to all types of electronic applications. The complexity of electronic systems has been increasing due to increase in the number of functions and features offered to the users. At the same time the number of devices working per unit volume of the system has increased enormously, due to which the power density per unit volume has increased. Dissipating high power in small volumes has increased the thermal problems in all types of electronic systems, including medical gadgets. Thermal stress has been identified to be the major cause of failure of electronic devices in electronic systems, based on the analysis of failures, based on research work. The causative mechanism of failure of semiconductor device package due to thermal overstress in medical electronic systems is the differential expansion between plastic and metal parts of the device which causes a differential strain and package failure. Selection of materials with similar coefficient of thermal expansion is important to prevent thermal overstress caused failures. In this paper, we discuss a technique which uses mathematical analysis to provide a solution to this problem of selecting the suitable material to prevent differential thermal stress failures in medical electronics systems.