Ng Of Material Research Articles

Native Proteomics by Capillary Zone Electrophoresis-Mass Spectrometry.

Native proteomics measures endogenous proteoforms and protein complexes under a near physiological condition using native mass spectrometry (nMS) coupled with liquid-phase separations. Native proteomics should provide the most accurate bird's-eye view of proteome dynamics within cells, which is fundamental for understanding almost all biological processes. nMS has been widely employed to characterize well-purified protein complexes. However, there are only very few trials of utilizing nMS to measure proteoforms and protein complexes in a complex sample (i.e., a whole cell lysate). Here, we pioneer the native proteomics measurement of large proteoforms or protein complexes up to 400 kDa from a complex proteome via online coupling of native capillary zone electrophoresis (nCZE) to an ultra-high mass range (UHMR) Orbitrap mass spectrometer. The nCZE-MS technique enabled the measurement of a 115-kDa standard protein complex while consuming only about 0.1 ng of protein material. nCZE-MS analysis of an E.coli cell lysate detected 72 proteoforms or protein complexes in a mass range of 30-400 kDa in a single run while consuming only 50-ng protein material. The mass distribution of detected proteoforms or protein complexes agreed well with that from mass photometry measurement. This work represents a technical breakthrough in native proteomics for measuring complex proteomes.

Native Proteomics by Capillary Zone Electrophoresis‐Mass Spectrometry

Native proteomics measures endogenous proteoforms and protein complexes under a near physiological condition using native mass spectrometry (nMS) coupled with liquid‐phase separations. Native proteomics should provide the most accurate bird’s‐eye view of proteome dynamics within cells, which is fundamental for understanding almost all biological processes. nMS has been widely employed to characterize well‐purified protein complexes. However, there are only very few trials of utilizing nMS to measure proteoforms and protein complexes in a complex sample (i.e., a whole cell lysate). Here, we pioneer the native proteomics measurement of large proteoforms or protein complexes up to 400 kDa from a complex proteome via online coupling of native capillary zone electrophoresis (nCZE) to an ultra‐high mass range (UHMR) Orbitrap mass spectrometer. The nCZE‐MS technique enabled the measurement of a 115‐kDa standard protein complex while consuming only about 0.1 ng of protein material. nCZE‐MS analysis of an E.coli cell lysate detected 72 proteoforms or protein complexes in a mass range of 30‐400 kDa in a single run while consuming only 50‐ng protein material. The mass distribution of detected proteoforms or protein complexes agreed well with that from mass photometry measurement. This work represents a technical breakthrough in native proteomics for measuring complex proteomes.

Native Proteomics by Capillary Zone Electrophoresis-Mass Spectrometry.

Native proteomics measures endogenous proteoforms and protein complexes under a near physiological condition using native mass spectrometry (nMS) coupled with liquid-phase separations. Native proteomics should provide the most accurate bird's-eye view of proteome dynamics within cells, which is fundamental for understanding almost all biological processes. nMS has been widely employed to characterize well-purified protein complexes. However, there are only very few trials of utilizing nMS to measure proteoforms and protein complexes in a complex sample (i.e., a whole cell lysate). Here, we pioneer the native proteomics measurement of large proteoforms or protein complexes up to 400 kDa from a complex proteome via online coupling of native capillary zone electrophoresis (nCZE) to an ultra-high mass range (UHMR) Orbitrap mass spectrometer. The nCZE-MS technique enabled the measurement of a 115-kDa standard protein complex while consuming only about 0.1 ng of protein material. nCZE-MS analysis of an E . coli cell lysate detected 72 proteoforms or protein complexes in a mass range of 30-400 kDa in a single run while consuming only 50-ng protein material. The mass distribution of detected proteoforms or protein complexes agreed well with that from mass photometry measurement. This work represents a technical breakthrough in native proteomics for measuring complex proteomes.

Soft Sensor Technology for the Determination of Mechanical Seal Friction Power Performance

Mechanical seals ensure the internal sealing of centrifugal pumps from the surrounding environment. They are one of the most critical components in a centrifugal pump. For this reason, the condition of mechanical seals should be monitored during operation. Mechanical seal friction power is an important component of mechanical losses in centrifugal pumps and is used as an indicator of wear and therefore seal condition. The soft sensor described in this paper is based on temperature measurements at the seal and can be used for determining the frictional power performance. A major factor in determining frictional power performance is the heat transfer between the mechanical seal and the medium inside the pump. For calculating the heat transfer, the stationary temperature fields in the rings of the mechanical seal are described by transmission efficiencies. The root mean squared error was determined for steady-state operating conditions to assess the quality of the soft sensor calculation. The frictional power performance can be determined by recording the temperature at the mechanical seal mating ring and the medium. The algorithm detects when the steady-state operating conditions change but does not map the dynamic changes between the stationary operating conditions.

Performance Evaluation of Strengthened Scrapped Mating Rings of Face Seals Used as Single Point Turning Tool

The scrapped mating ring of face seals has been studied and recycled into single point turning tools (SPTTs) and performed comparably with standard turning tools. Three sets of tools, namely, standard tungsten tool, strengthened and unstrengthened scrapped ring, have been studied and performed satisfactorily as SPTTs. Standard tungsten tool, strengthened and unstrengthened scrapped mating ring of face seal respectively. The tools were configured with a nose radius 2mm, positive rake angles of 3o, 5o and 8o and used to perform turning operations on mild carbon steel (CS1030) with surface roughness measured. The results showed that the strengthened tools generated the best surface finish for mild carbon steel among all three tools under consideration. The statistical analysis showed that surface finish, the model, cutting speed and feed rate are significant with their P-values < 0.0001 but the depth of cut, rake angle and tool have no significant impact on surface finish at 95% confidence level. This research will provide the machine tools shop with more durable SPTT and enhance reliability, quality, minimize downtimes and accidents in machining processes.

Development and Validation of a Segregated Conjugate Heat Transfer Procedure on a sCO2 Dry Gas Seal Test Bench

Abstract Carbondioxide at supercritical state shows particularly favorable thermodynamic properties for closed-loop Brayton and Rankine cycles. High density, close to a liquid, and low viscosity, close to a gas, drive to achieve higher energy conversion efficiency with smaller size turbines and components. Since minimizing the sCO2 leakage flows drives to a further increasing of overall efficiency, dry gas seals (DGS) are considered as a key enabling technology for achieving this purpose and for achieving a carbon footprint in line with the increasingly stringent targets. DGSs are gas-lubricated, mechanical, noncontacting, end-face seals, consisting of a mating (rotating) ring and a primary (stationary) ring. The operating equilibrium clearance of the seal is determined by the balance of opening dynamic forces, mainly depending on angular velocity and grooves shape, and closing forces caused by pressure gradients and spring force. Due to high rotational speeds, typical small size sealing gaps (order of magnitude of Micron), high fluid pressure and density, the heat generated by friction through the seal has a large impact on the temperature distribution, therefore a thermal design is needed to stay below the seal allowable temperature; this requirement has been even amplified in the last years with the DGS application to hot turbomachinery. Nowadays, numerical conjugate heat transfer (CHT) analysis is a good industrial practice to quantify the thermal distribution in turbomachinery components. On the other hand, due to different order of magnitude of secondary flows cavity sizes and DGS seal gaps, simulating the whole fluid domain with three-dimensional (3D) computational fluid dynamic (CFD) calculation could drive to prohibitive computational costs. In this regard, this paper presents a fast numerical iterative procedure based on a commercial one-dimensional flow network modeler (altair flow simulator), with real gas effects included, coupled with a commercial finite element solver (ansys mechanical). Additional 3D CFD simulations are carried out to enhance the predictability of the fluid solver in specific critical areas. The proposed procedure is applied and validated in a DGS specific test bench designed, owned and operated by Flowserve. The validation dataset has been generated operating the DGS in the test bench at 15 different conditions in terms of angular velocity and housing temperature with sCO2 as working fluid aligned with those expected on the unit. Test rig consists of a rotor and housing where the turbomachine operating condition (pressure, speed, temperature and sealing fluid) are mirrored to verify the seal performance. The rig is equipped with test seal and a plug seal mounted in a back-to-back configuration. Data set used for this comparison is composed by thermocouples on the statoric rings, retainers and housing of each seal, operating at five different angular speeds and three minimum levels of housing temperature (100 °C, 210 °C, and 250 °C). These temperatures are designed to mirror turbomachinery conditions around the seal, and, if friction heat is not enough to guarantee them, a series of 18x1 kW heating elements circumferentially distributed in the test bench housing, are activated. The nominal operating condition has been considered as the starting point of the model predictions and, there, several sensitivity analyses have been carried out to align the model to test bench measurements; then, the selected configuration has been frozen and used to assess the model performance on other operating conditions. The numerical results have shown a good agreement with experimental data at each operating condition in terms of punctual temperatures previously described and with extremely low computational times.

Dancing the Nanopore limbo – Nanopore metagenomics from small DNA quantities for bacterial genome reconstruction

BackgroundWhile genome-resolved metagenomics has revolutionized our understanding of microbial and genetic diversity in environmental samples, assemblies of short-reads often result in incomplete and/or highly fragmented metagenome-assembled genomes (MAGs), hampering in-depth genomics. Although Nanopore sequencing has increasingly been used in microbial metagenomics as long reads greatly improve the assembly quality of MAGs, the recommended DNA quantity usually exceeds the recoverable amount of DNA of environmental samples. Here, we evaluated lower-than-recommended DNA quantities for Nanopore library preparation by determining sequencing quality, community composition, assembly quality and recovery of MAGs.ResultsWe generated 27 Nanopore metagenomes using the commercially available ZYMO mock community and varied the amount of input DNA from 1000 ng (the recommended minimum) down to 1 ng in eight steps. The quality of the generated reads remained stable across all input levels. The read mapping accuracy, which reflects how well the reads match a known reference genome, was consistently high across all libraries. The relative abundance of the species in the metagenomes was stable down to input levels of 50 ng. High-quality MAGs (> 95% completeness, ≤ 5% contamination) could be recovered from metagenomes down to 35 ng of input material. When combined with publicly available Illumina reads for the mock community, Nanopore reads from input quantities as low as 1 ng improved the quality of hybrid assemblies.ConclusionOur results show that the recommended DNA amount for Nanopore library preparation can be substantially reduced without any adverse effects to genome recovery and still bolster hybrid assemblies when combined with short-read data. We posit that the results presented herein will enable studies to improve genome recovery from low-biomass environments, enhancing microbiome understanding.

Face grooves for state monitoring in dry gas seals

The monitoring of abnormal states of dry gas seals is a critical but challenging task for equipment reliability. This paper proposes an end-face groove structure oriented to the condition monitoring of dry gas seals. In addition to hydrodynamic grooves on the end face of the mating ring, seven special monitoring grooves are manufactured on the other side of the dual end face. These monitoring grooves can induce characteristics of end-face contact that can be detected by an acoustic emission sensor, where the primary characteristic is the seven times the motor speed frequency(7-TMSF). Simulations are conducted using a dynamic model to help establish the monitoring method.

Thermus thermophilus Argonaute-Based Isothermal Amplification Assay for Ultrasensitive and Specific RNA Detection.

Recent advances in prokaryotic Argonaute proteins (pAgos) as potential genome-editing tools have provided new insights into the development of pAgos-based nucleic acid detection platforms. However, pAgos-based isothermal detection remains challenging. Here, we report a true isothermal amplification strategy, termed Thermus thermophilus Argonaute-based thermostable exponential amplification reaction (TtAgoEAR), to detect RNA with ultrasensitivity and single-nucleotide resolution at a constant temperature of 66 °C. We demonstrate the reliable detection of lncRNA, mRNA, and virus RNA with attomolar sensitivity and that TtAgoEAR can be applied to detect RNA targets in in cell lines, saliva, and tissues. We utilize this assay to distinguish pancreatic cancer cells carrying the mutation from wild-type cells with as little as 2 ng of RNA material. We also show that TtAgoEAR is easily adaptable to a lateral-flow-based readout. These results demonstrate that TtAgoEAR has great potential to facilitate reliable and easy RNA detection in point-of-care diagnosis and field analysis.

(Invited) Resonator and SERS Sensing in the Field of Drug Delivery

Introduction Our research center of excellence IDUN combines research in nanosensors/centrifugal microfluidics and microfabricated devices for oral drug delivery. This allows us to explore the synergy between sensor development and search for new pharmaceutical delivery tools and materials. Our developed nanosensors get access to unique polymers and biomolecules and are able to characterize, among others, small volumes of materials and molecules, which are today not possible to analyze by any standard technologies. We will show examples of recent findings and results within drug/polymer characterization (1) and process monitoring (2) using nanomechanical sensors. Also, new applications within therapeutic drug monitoring using Surface Enhanced Raman Scattering (SERS) will be presented as well as sensor integration with centrifugal microfluidics platforms. Resonators By monitoring the resonance frequency shift of micrometer sized strings or cantilevers coated with thin layers of polymers, it is possible to monitor phase transitions using only ng of material. We have been able to observe beta relaxation of polymers (3) and drugs (2), see figure 1. These systems also allowed us to monitor degradation of biomaterials used in the fabrication of the microcontainers (4). Also, strings are inherently sensitive to temperature changes (5). The resonant frequency detunes as a function of temperature and temperature changes down to 10-5 °C can be detected. The effect has been used to perform photothermal IR spectra on samples deposited on resonating strings and resonating filters. This has been used to for example study the amorphous and crystalline forms of indomethacin (1). As an alternative to cleanroom fabricated resonators we have used single drug and collagen particles as micro mechanical resonators, thereby eliminating the need for cleanroom processing. This method additionally makes it possible to study the behavior of single crystals, which would otherwise be extremely difficult/impossible. This method has, among others, allowed us to study new phenomena in the hydration/dehydration of drugs (6). Centrifugal microfluidics The optics and mechanics from a DVD player can be used to realize compact and sensitive sensor systems. By rotating a polymer disc with integrated microfluidic channels it is possible to manipulate liquid samples such as blood – performing crucial operations like separation, valving and mixing. We integrate sensor elements such as cantilevers, nanoparticles, resonating strings and SERS substrates with centrifugal microfluidics (7). The sensors are read out by a DVD pick-up head, which can perform transmission/absorption measurements and can detect nm deflections. Also, electrodes and spectrometers are integrated on a disc platform, facilitating electrochemical/Raman measurements. Our nanopillar SERS substrate can be used for sample filtration and separation. Here the nanopillars function similarly to a filter paper in chromatography and can be used to distinguish e.g. different components in a urine sample as well as drug residuals. A SERS chip is placed in a centrifugal microfluidics platform, whereby the sample can be initially centrifuged. Subsequently half the SERS chip is exposed to the centrifuged liquid. Hereby, liquid can travel up the chip by the so-called wicking effect, and depending on affinity of molecules to the surface, different molecules will travel different lengths. Hereby, a separation is secured and the different molecules are read-out as bands on the SERS chip. Acknowledgements This research has received funding from the ERC grant agreement n° 320535 and from the Center of Excellence ’IDUN’ granted by Danish National Research Foundation, DNRF122/the Velux Foundations.

(Invited) Resonator and SERS Sensing in the Field of Drug Delivery

Introduction Our research center of excellence IDUN combines research in nanosensors/centrifugal microfluidics and microfabricated devices for oral drug delivery. This allows us to explore the synergy between sensor development and search for new pharmaceutical delivery tools and materials. Our developed nanosensors get access to unique polymers and biomolecules and are able to characterize, among others, small volumes of materials and molecules, which are today not possible to analyze by any standard technologies. We will show examples of recent findings and results within drug/polymer characterization (1) and process monitoring (2) using nanomechanical sensors. Also, new applications within therapeutic drug monitoring using Surface Enhanced Raman Scattering will be presented as well as sensor integration with centrifugal microfluidics platforms. Resonators By monitoring the resonance frequency shift of micrometer sized strings or cantilevers coated with thin layers of polymers, it is possible to monitor phase transitions using only ng of material. We have been able to observe beta relaxation of polymers (3) and drugs (2), see figure 1. These systems also allowed us to monitor degradation of biomaterials used in the fabrication of the microcontainers (4). Also, strings are inherently sensitive to temperature changes (5). The resonant frequency detunes as a function of temperature and temperature changes down to 10-5 °C can be detected. The effect has been used to perform photothermal IR spectra on samples deposited on resonating strings and resonating filters. This has been used to for example study the amorphous and crystalline forms of indomethacin (1). Centrifugal microfluidics The optics and mechanics from a DVD player can be used to realize compact and sensitive sensor systems. By rotating a polymer disc with integrated microfluidic channels it is possible to manipulate liquid samples such as blood – performing crucial operations like separation, valving and mixing. We integrate sensor elements such as cantilevers, nanoparticles, resonating strings and surface enhanced Raman scattering (SERS) substrates with centrifugal microfluidics (6). The sensors are read out by a DVD pick-up head, which can perform transmission/absorption measurements and can detect nm deflections. Also, electrodes and spectrometers are integrated on a disc platform, facilitating electrochemical/Raman measurements. Acknowledgements This research has received funding from the ERC grant agreement n° 320535 and from the Center of Excellence ’IDUN’ granted by Danish National Research Foundation, DNRF122/the Velux Foundations.

Dynamic Analysis of the Stick-Slip Phenomenon in an Automotive Water Pump

In this paper, we present a study on the stick-slip torsional vibration of the spinning shaft in an automotive water pump. We propose a dynamic rotor model with a pulley, an impeller, a mechanical seal and a shaft to analyze the stick-slip vibration of a water pump. The dynamic states of the mechanical seal are classified into stick and slip states depending on whether the seal and mating rings of the mechanical seal have relative motion or not. We derived the partial differential equations of motion and the corresponding boundary conditions for each state of the seal. In addition, we established a judgement criterion for the stick and slip states of the seal. After the equations of motion were discretized by a proposed finite element procedure, the dynamic responses of the rotor system of a water pump were computed by using the generalized-a time integration method. Furthermore, we analyzed the effects of various system parameters on stick-slip vibration, including the mass moment of inertia for the pulley, the drag torque at the impeller, the external torque at the pulley, and the normal force between the seal and mating rings.

Pengembangan Strategi Pembelajaran Pengkonkritan Materi Abstrak PAI Anak Usia Dini di RA Perwanida 3 Palembang

Early childhood who are in the preoperational stage have not been able to think logically and abstractly, but Islamic religious subjects that must be instilled in children from an early age especially the aspects of aqidah are included in the abstract material category, thus learning strategies are needed that can make it easier for students to understand abstract material the. This study aims to produce a learning strategy for the abstracting of PAI abstract material for early childhood in RA Perwanida 3 Palembang, knowing the results of expert validation, and knowing the effectiveness of the learning strategy for the abstracting of PAI abstract material for early childhood in RA Perwanida 3 Palembang. This research is research and development. The research and development stages are requirements analysis, planning, product design development, product validation and revision, trials and revisions, final product. The results of the study are: 1) the product developed in the form of a draft learning strategy design, 2) the learning strategy is assessed and validated based on the aspects of the suitability of the media and methods to the material, student characteristics, time allocation and infrastructure, the results of the assessment of learning strategies obtain an average score 4.62 with the category "very appropriate", 3) the average test score of 13 students before using the developed learning strategy is 6.3885 while after using the developed learning strategy the average student score is 7.3462. While the paired samples test obtained 0.000 significance less than the 0.05 significance level. Based on the results of the assessment, the learning strategy of abstracting PAI material in early childhood in RA Perwanida 3 Palembang is effective and feasible to use.

Frictional characteristics of impregnated graphite with different graphitization degree versus chromium stainless steel under varying PV values

An experimental study was performed by employing a seal pair of phenolic resin impregnated graphite and high chromium martensitic stainless steel 9Cr18. A purpose-built test rig was designed and fabricated to study the effect of face temperature on the surface morphology of a seal ring made of phenolic resin impregnated graphite with different graphitization degrees for varying PV values (pressure × velocity). As revealed by the results, the effect of rotational speed on heat generation between the two mating surfaces was more significant than that of fluid pressure. The effects of surface frictional temperature between the two faces were found different when the phenolic resin impregnated graphite ring with different graphitization degrees. The worn surfaces of the phenolic resin impregnated graphite rings were examined with the assistance of scanning electron microscopy and 3D measuring laser microscopy to investigate the wear mechanism for these different mating rings. Both adhesive and abrasive wear mechanisms were discovered under the working conditions. It was found out that the phenolic resin impregnated graphite ring with a high degree of graphitization was worn more severely at high PV values. Under the conditions of high speeds or high PV values, the phenolic resin impregnated graphite with fine and compact graphite matrix particles, medium degree of graphitization, high thermal conductivity and hardness is the top choice.

Abstract 432: Novel method for NGS analysis of actionable mutations in circulating tumor DNA specimens: improved quality control and 20-fold lower sequencing required

Abstract Background: Identification of actionable mutations in circulating tumor DNA (ctDNA) enables gene-targeted therapy of solid tumors based on a simple blood test. NGS methods that attach a unique molecular identifier (UMI) to each DNA molecule reduce variant allele fraction (VAF) limit of detection (LOD) to <0.01% at a cost of 10-20-fold higher sequencing requirement. Importantly, the VAF lower limit of detection (LOD) for analysis of ctDNA specimens does not typically extend below 0.5% due to limits of ctDNA specimen quantity. For example, the average ctDNA specimen is 32 ng (10,000 genome copies) and at 0.1% VAF, 10 mutant molecules would be added to library prep. At this level, signal loss during library prep (typically 70-90%) will be associated with stochastic sampling variation. For example, in the Sequencing Quality Control Consortium (SEQC) 2 study, we measured inter-site and inter-replicate reproducibility of VAF measurement in 50 ng (15,000 genome copies) of synthetic ctDNA reference material. Thus, even using UMI NGS, measurement, reproducibility at VAF >0.5% was >95%, but reproducibility at 0.1-0.5% VAF was about 70%. Given limited value of UMI NGS when size of ctDNA specimen restricted VAF LOD to 0.5%, we tested the hypothesis that synthetic internal standard (IS) spike-in molecules provide reliable alternative quality control while eliminating UMI-imposed sequencing burden. Methods: We synthesized IS for 61 actionable mutations, cloned them into pUC vectors, confirmed each IS to be wild-type sequence, linearized, quantified abundance and combined at a 1:1 genome copy mixture. An aliquot of IS mixture was added to the ctDNA reference material at 1:1 genome copy prior to library prep, followed by Illumina HiSeq sequencing, separation of target from IS reads using custom splitter, then pipeline analysis on Qiagen CLC Genomics Workbench. Results: Analysis of each target relative to IS reliably identified base-substitution sequencing errors at each measured actionable mutation site and determined that VAF for each was <0.2%. Further, although a typical UMI method requires >200,000 reads per target in each sample, with analysis relative to IS spike-ins, 20,000 reads was sufficient (10,000 reads for the specimen and 10,000 reads for the spike-in). Because the IS spike-in molecules were validated to be wild-type, any variants were assumed to be due to technical error. Thus, a z-score comparing sequence count for a) specimen wild-type, b) specimen mutant, c) IS wild-type, and d) IS mutant enabled calculation of confidence level regarding each biological variant call. Conclusion: Preliminary data indicate that IS spike-in mixtures enable reliable analysis of ctDNA mutation fraction to LOD of 0.5% without need for UMI. Disclaimer: The views expressed here are those of the authors only and do not necessarily express the views/policies of the FDA. Citation Format: Daniel J. Craig, Erin L. Crawford, Joshua Xu, Thomas M. Blomquist, Leihong Wu, Thomas Morrison, James C. Willey. Novel method for NGS analysis of actionable mutations in circulating tumor DNA specimens: improved quality control and 20-fold lower sequencing required [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 432.

Massing a laser-induced plasma with atomic absorption spectroscopy

A new technique, pseudocontinuum source atomic absorption spectroscopy, is used to map neutral atomic populations in a titanium laser-ablation plasma under helium cover. Measurements show good reproducibility and spatial resolution adequate to measure inhomogeneity in atmospherically-confined LIBS plasmas. 160 ± 20 ng of material is imaged across four terms (one ground and three metastable) of the neutral atom. This mass exceeds the crater volume, indicating substantial redeposition within the crater from pulse to pulse. At five microseconds comparison of the ground and the lowest metastable terms indicates departure from local thermodynamic equilibrium conditions. The technique shows promise for understanding the evolution of these inhomogeneous plasmas, particularly the fate of ablated material.

Method validation parameters for drugs and explosives in ambient pressure ion mobility spectrometry

An approach using method validation (MV) parameters, otherwise known as analytical figures of merit was combined with electrospray ionization high performance ion mobility spectrometry (ESI-HPIMS) to describe an approach for evaluating drugs and explosives analysis in the field. MV parameters such as reduced mobility (K o ), conditional reduced mobility (K c ), resolving power (R p ), theoretical plates (N), linearity, accuracy, precision, limit of detection (LOD), limit of quantitation (LOQ), repeatability, range, and reporting limit were investigated and developed for eleven drugs and six explosives. Our investigation estimated resolving power at 66 ± 0.64 for the ESI-HPIMS used. The LOD’s calculated ranged from 0.45–2.97 ng of material electrosprayed into the ESI-HPIMS. The LOQ’s calculated falls in the range 4.11–8.63 ng of material electrosprayed into the ESI-HPIMS. The key findings from this investigation were the following: K c proves to be a measure of the identity of an explosive or drug ion; a parameter that may be applied to help aid IMS devices when detecting drugs and explosives. MV parameters, especially, K c , introduced in this study is an effective parameter for establishing a unique identity of a drug or explosive. A control chart is an effective way to monitor the performance of an instrument and may be a useful tool for establishing reliability of confirmatory data in forensic investigations. MV parameters may be a reliable, accurate and unique identification marker for target drugs and explosives capable of differentiating these substances from false positive responses.

AKTIVITAS KUAU RAJA (Argusianus argus Linnaeus, 1766) PADA MATING RING DI HUTAN KONSERVASI KALAWEIT SUPAYANG, SOLOK, SUMATERA BARAT

A behavioral study of Great Argus Pheasants (Argusianus argus Linnaeus, 1766) at their mating ring has been done from October 2015 to January 2016 in The Kalaweit Supayang Conservasion Forest, Solok, West Sumatra. The purpose of this research is to know about activities of Great Argus Pheasant and how their activities done. Field observation in the mating ring was conducted using ten video camera traps for three months at their mating ring. Those cameras were activated for 60 seconds per session by 10 seconds intersession intervals. Behavioral data were tabulated from video records using continuous recording method. There were eight activities of Great Argus Pheasant at their mating ring which divided into individual and pairmate activities. The individual activities of male included clearing, walking, vigilance, feeding, grooming, resting, and calling. While female activities included resting, grooming, and walking. Activity with pairmate was dancing where male performed dancing only in the present of female. Male spent 26 times longer than females appeared at the mating ring. The peak activities at mating ring was in the morning between 7:00 and 8:00 am.

Physical aging in PLA through standard DSC and fast scanning calorimetry investigations

Physical aging on wholly amorphous polylactide (PLA) has been performed by means of standard differential scanning calorimetry (DSC) and fast scanning calorimetry (FSC) just below its glass transition. Compared to the in-situ aging study through the standard DSC, an increase of 80–90% has been observed in the enthalpy recovery by FSC investigations. Such increase has been related to the high cooling rates used by FSC. Besides, an influence of the sample geometry has been measured when glasses are vitrified by high cooling rates. This implies that the critical thickness involved in the physical aging acceleration is cooling rate dependent. High cooling rates allow to reach the thermodynamic equilibrium, as observed from physical aging investigations by FSC. In addition, few ng of material analyzed by FSC are representative of the bulk one analyzed by standard DSC, when the glass is formed in the same conditions.

Spiral-grooved gas face seal for steam turbine shroud tip leakage reduction: Performance and feasibility analysis

In order to minimize shroud leakage and its effect on aerodynamic loss of steam turbines, a new shroud seal design by employing spiral-grooved gas face seal theory is presented. To verify the method, a flow numerical simulation was conducted to investigate the effect of the new shroud seal on aerodynamic loss in steam turbine rotor row. The results show, compared with a traditional two-tooth labyrinth seal, the new shroud seal leakage is reduced by 99.3%, and the rotor row efficiency is improved by 1.9%. Furthermore, a feasibility analysis including lift and stiffness of gas film, tracking response of primary ring and deformation of mating ring was presented. The present design is a potential approach to further improve turbine stage performance.