Genetic Distance of Four Strains of Guppy Fish (Poecilia reticulata) Using RAPD PCR Method

Guppies are one type of organism that can live well, especially in the tropics. The kinship between species that have genetic similarities can be identified through genotypic mapping, one of which is molecular analysis using. RAPD method with PCR technique. This study aims to determine the genetic relationship of four guppy poecilia reticulata strains, respectively are Albino Full Red (AFP), Brazilian Fan Tail (BFT), Koi Guppy Tuxedo (KGT), and Platinum Red Tail Big Ears (PRTB) with the RAPD-PCR method. The genetic relationship data obtained is used as a guide for mating between the four strains. This research was conducted from September 2020 to November 2020. The process were carried out at the Biotechnology Laboratory, Faculty of Fisheries and Marine Sciences, Padjadjaran University and the Central Laboratory, Padjadjaran University. OPA-03 primer (AGTCAGCCAC) is used as a standard parameter to interpret genetic diversity among the four guppy strains. Based on the results, amplification with primer OPA-03 visualized 21 bands consisting of seven polymorphic bands and 13 monomorphic bands. The results of the phylogenetic tree showed that there were two groups. The first group is AFR and BFT a similarity index of 69.5%. The second group is KGT and PRTB a similarity index of 71.5%.

Standardization of Simplicia and Ethanol Extract of Purun Danau (Lepironia articulata (Retz.) Domin) Rhizome

Purun Danau (Lepironia articulata (Retz.) Domin) has been shown to have antimalarial and antioxidant activity. This study aimed to standardize simplicia and extract of L. articulata by determining the value of its specific and non-specific parameters. A sampling of L. articulata rhizome was carried out in Guntung Manggis, Haur Gading, and Halat. The standardization method used was based on the Indonesian Herbal Pharmacopoeia and the General Standard Parameter of Extract. The organoleptic observations showed that L. articulata simplicia was reddish-brown in color, chelated taste, and had a specific odor. Microscopic observation showed parts of this plant: epidermis, cortex, endodermis, parenchyma, bundle vessels, and scalariform vessels. Ethanol-soluble extract content was 10.00-12.66%, water-soluble extract content 8.03-10.87%, drying shrinkage 7.10-7.33%, total ash content 2.03-2.52%, acid-insoluble ash 0.33-0.42%, Pb content 5.698-9.989 ppm, Cd content 0.300-0.500 ppm, Hg content 0.070-0.090 ppm. Ethanol extract of L. articulata rhizome contained alkaloids, flavonoids, tannins, glycosides, and saponins. The yield obtained was 8.05-11.23%, total ash content was 1.58-1.67%, acid-insoluble ash was 0.23-0.33%, and water content was 7.10-8.50%. Standardization of simplicia and ethanol extract of L. articulata rhizome has met the criteria.

Surface roughness variance on different levels of surface inclination of powder bed fused tool steel 1.2709

Evolution of additive manufacturing has allowed increased flexibility and complexity of designs over conventional manufacturing e.g. formative and subtractive manufacturing. Restricting factor of laser powder bed fusion of metals (PBF-LB/M) additive manufacturing is the as-built surface quality. To promote an understanding of the surface roughness and suitable surface measuring technologies octagon shaped tool steel 1.2709 samples was developed and manufactured. Different surface measuring technologies was also literary reviewed. Studied samples were manufactured with commercially available laser-based powder bed fusion system using standard parameter set provided by the system manufacturer. Surface roughness was measured from top and down skins from multiple different building angles in a way that process specific effects, such as direction of movement of the powder re-coater, was considered. Based on these measuring results of the samples the effect surface inclination are discussed. The results show that building angle strongly affects to surface roughness of laser-based powder bed fused parts. Surface roughness was measured to be more than five times worse in unsupported angle manufactured down facing surfaces when compared with vertical walls.

Precision Evaluation of the DC Decay Method for Accurate Characterization of Wound-Field Synchronous Machines and Comparison with the Sudden Short-Circuit

The sudden short-circuit is considered the gold-standard parameter measurement method for wound-field synchronous machines (WFSMs) as it enables the recording of the characteristic quantities in near-to-real conditions. However, the test needs huge pieces of equipment, but even worse, it reduces the lifetime of the electrical components by up to 10 years due to the high winding overhang mechanical forces. The DC-Decay tests are low-power alternatives to obtain the characteristic quantities without damaging the machinery. To allow wider use of this method, there are a couple of challenges left that are tackled by this paper. The two main open challenges are, firstly, the number of measurements needed to reach a particular precision, and secondly, a comparison of the DC-Decay with the sudden short-circuit test to allow the validation against the gold standard. More detailed, this paper explores the main challenges associated with the practical use of the DC decay method, which is a non-conventional and detailed-level approach to characterize WFSMs. We provide replies and recommendations regarding the number of measurements, suggesting the minimum number of recorded tests needed to obtain the equivalent diagram with a given accuracy, which has been further validated with an experimental case study. Moreover, the potential enhancement and precision of the parameter identification algorithm are studied in detail. Finally, the equivalent parameters of the DC decay method are compared to the gold standard, which concludes on what the characterization means in terms of predicting accurate transient short-circuit currents for WFSMs.

Precision Evaluation of the DC Decay Method for Accurate Characterization of Wound-Field Synchronous Machines and Comparison with the Sudden Short-Circuit

The sudden short-circuit is considered the gold-standard parameter measurement method for wound-field synchronous machines (WFSMs) as it enables the recording of the characteristic quantities in near-to-real conditions. However, the test needs huge pieces of equipment, but even worse, it reduces the lifetime of the electrical components by up to 10 years due to the high winding overhang mechanical forces. The DC-Decay tests are low-power alternatives to obtain the characteristic quantities without damaging the machinery. To allow wider use of this method, there are a couple of challenges left that are tackled by this paper. The two main open challenges are, firstly, the number of measurements needed to reach a particular precision, and secondly, a comparison of the DC-Decay with the sudden short-circuit test to allow the validation against the gold standard. More detailed, this paper explores the main challenges associated with the practical use of the DC decay method, which is a non-conventional and detailed-level approach to characterize WFSMs. We provide replies and recommendations regarding the number of measurements, suggesting the minimum number of recorded tests needed to obtain the equivalent diagram with a given accuracy, which has been further validated with an experimental case study. Moreover, the potential enhancement and precision of the parameter identification algorithm are studied in detail. Finally, the equivalent parameters of the DC decay method are compared to the gold standard, which concludes on what the characterization means in terms of predicting accurate transient short-circuit currents for WFSMs.

Interleaved Half-Bridge Submodules with Sensorless Leg Current Balancing in Modular Multilevel Converters

A new state observer-based current balancing method for Modular Multilevel Converters with Interleaved half-bridge Sub-Modules (ISM-MMC) is presented in this paper. The developed observer allows estimating currents through interleaved half-bridge legs in each submodule of ISM-MMC basing only on arm current and submodule’s capacitor voltage measurements. Then, the interleaved current balancing control uses the estimated currents to reduce the interleaved currents imbalance caused by upstream control actions. This technique minimizes the number of required current sensors in ISM-MMC, thereby reducing the converter's cost, weight, and volume. Capabilities of the proposed interleaved currents sensorless balancing control has been tested against standard parameter tolerances of the composing passive elements. The feasibility of the proposed method is verified by extensive simulation and experimental tests.

Interleaved Half-Bridge Submodules with Sensorless Leg Current Balancing in Modular Multilevel Converters

A new state observer-based current balancing method for Modular Multilevel Converters with Interleaved half-bridge Sub-Modules (ISM-MMC) is presented in this paper. The developed observer allows estimating currents through interleaved half-bridge legs in each submodule of ISM-MMC basing only on arm current and submodule’s capacitor voltage measurements. Then, the interleaved current balancing control uses the estimated currents to reduce the interleaved currents imbalance caused by upstream control actions. This technique minimizes the number of required current sensors in ISM-MMC, thereby reducing the converter's cost, weight, and volume. Capabilities of the proposed interleaved currents sensorless balancing control has been tested against standard parameter tolerances of the composing passive elements. The feasibility of the proposed method is verified by extensive simulation and experimental tests.

Validity of Urine Syndecan-1 as A Predictor of Acute Kidney Injury In Pediatric Sepsis Patients

Introduction: AKI (Acute Kidney Injury) complications in sepsis patients generally occur 24 hours after admission to ICU. Creatine Serum Concentration is a standard parameter to diagnose AKI. Unfortunately, the changes in creatine serum concentration will only be seen several days after the decrease of renal function to 50%. The low detection ability has been linked with time loss before preventive therapy is commenced. Furthermore, this instigates the need for biomarkers to ensure early detection. Objective: This study aimed to identify cut-off points of urine syndecan-1 and to measure the prediction ability of urine syndecan-1 towards the AKI occurrence in pediatric sepsis patients. Materials and methods: This study was a prospective cohort study performed at a single center in Dr. Soetomo General Hospital, Surabaya. The inclusion criterion was all children admitted to the resuscitation room from October until December 2019. Furthermore, urine sampling is carried out at 0, 6, 12, and 24 hours for a syndecan-1 urine examination, and every procedure performed on the patient will be recorded. This action was continued up to the third day and aimed to evaluate some factors related to AKI at 48-72 hours of admission. Result and Discussion: Out of 41 pediatric sepsis patients, 30 patients fulfilled the inclusion criteria and 57% had AKI. The value of urine syndecan-1 at hour-0 and hour-6 was significantly featured a cut-off point. Conclusion: The value of urine syndecan-1 at hour-0 and hour-6 are valid parameters to predict the occurrence of AKI grades 1, 2, and 3 in pediatric septic patients at 48-72 hours after their hospital admission. The best cut-off value of urine syndecan-1 at the 0th hour was 0.67 ng/ml.

Forensic Investigation of Bullet Holes for Determining Distance from Glass Fracture Analysis

The study of glass fracture patterns has been of long interest to the forensic community. Fragments of glass can be significant evidence found in the investigation of various types of offenses especially where armed violence is involved on automobiles. Figuring out, whether glass fragments present on crime scene share the same origin as per glass that has been hit by a projectile or any substrate, is quite a success to an examiner because that further leads to the investigation of how and by which means it has done. Holes occurred in the glass at the crime scenes have much importance and many attempts are taken to investigate the properties of these glass holes to find the type, speed, and angle of the projectile which probably produce the hole. For highvelocity projectiles including bullets, these bullet holes in glass can exhibit certain features and fractures. The objective of this research was to determine the distance of shooter from the bullet hole on glass used in automobiles. Bullet holes were prepared and different parameters of glass fractures like bullet hole diameter, cone fractures radius, cone fractures diameter, radial, and concentric fracture count were considered from both front and the backside of the glass. These parameters were observed and analyzed to determine the dependency of these parameters on the variable “distance”. The consistency found in the measurements to conclude our results were checked by goodness of fit test. The study bears great significance as it could lay down a foundation to set a standard parameter to estimate distance of bullet hole from shooter in firing incidents involving glass fracture. This will provide a blueprint to crime scene investigators in order to reconstruct the crime scene for understanding and to take investigation to logical conclusion.