Laboratory Hall Research Articles

JLab spectral functions of argon in nuwro and their implications for MicroBooNE

The Short-Baseline Neutrino program in Fermilab aims to resolve the nature of the low-energy excess events observed in LSND and MiniBooNE, and analyze with unprecedented precision neutrino interactions with argon. These studies require a reliable estimate of neutrino cross sections, in particular for charged current quasielastic scattering (CCQE). Here, we report updates of the uro Monte Carlo generator that, most notably, bring the state-of-the-art spectral functions to model the ground state properties of the argon nucleus, and improve the accuracy of the cross sections at low energies by accounting for the effects of the nuclear Coulomb potential. We discuss these developments in the context of electron and neutrino interactions, by comparing updated uro predictions to experimental data from Jefferson Laboratory Hall A and MicroBooNE. The MicroBooNE CCQE-dominated data are described with the χ2 per degree of freedom of 0.7, compared with 1.0 in the local Fermi gas model. The largest improvement is observed for the angular distributions of the produced protons, where the χ2 reduces nearly by half. Being obtained using the axial form factor parametrization from MINERvA, our results indicate a consistency between the CCQE measurements in MINERvA and MicroBooNE. Published by the American Physical Society 2024

Different Sandboxes: Past Emerging Leader Winners Talk Networking, Stress, and Work-Life Balance

For this special issue of LCGC, we caught up with five prior winners of our annual Emerging Leader Award to get their perspectives on how they first found success in the separation science field, how they have maintained and grown their reputations in the industry in the age of social media, and what they do to take their minds out of the laboratory or lecture hall.

Using Avida-ED Digital Organisms to Teach Evolution and Natural Selection Benefits a Broad Student Population

In instructional settings, evolution and natural selection are challenging concepts to teach, due to the fact that these topics are difficult to observe in the laboratory or lecture hall. In the past few years, Avida-ED has emerged as an innovative tool for teaching evolutionary principles. It allows students to directly observe effects of evolution by changing different variables, such as environmental conditions and genetic sequences. In our study, we used pretest and posttest questionnaires to investigate the use of Avida-ED in undergraduate coursework. We showed that students demonstrated similar improvement in evolutionary understanding irrespective of major, undergraduate level, sex, or final end-of-course grade. These results reinforce the idea that Avida-ED can facilitate learning of evolution in all student populations.

Magnetic field deflection in a 100 W Hall thruster with permanent magnets

The compact structure restrains the application of magnetic shielding in low-power Hall thrusters (LpHTs), leading to an asymmetric magnetic field or partial magnetic shielding of the channel wall. This study employs a trim coil to implement an asymmetric magnetic configuration in a 100 W laboratory Hall thruster. The locations of the maximum curvature of magnetic lines are deflected toward the inner and outer channel wall corresponding to the inward and outward deflected magnetic field configurations. Effects of the magnetic field deflection on the position of the ionization zone, efficiency of the thruster, discharge oscillations, and wall erosion are studied. Optical imaging and electrostatic probes are employed to monitor and scan the plasma beam. Experimental results show that the outward deflection induces a change in the magnetic mirror effect and alters the location of the ionization zone. The radial movement of the ionization zone away from the inner channel wall decreases the near-wall conductivity, reducing the electron current by 13.5% and promoting the current efficiency. Discharge oscillations are suppressed, and the propellant utilization efficiency is improved by 8.2%. Erosion of the channel wall shows an improvement of 40%. Generally, an outward deflected magnetic configuration can significantly improve the performance of LpHTs.

Effects of Bed Materials to Flow Characteristics on Open Channel and Gradually Varied Flow Simulation Using Genetic Algorithm (GA)

Determination of accurate roughness coefficient was realized necessary for hydraulic parameters estimation in open channel flow. For the purpose this study was planned to carry out on experimental basis in hydraulic laboratory hall of campus itself. In this study, a combination between experimental and numerical models study were carried out to investigate the influence of bed roughness on flow characteristics. Experiments were conducted on six bed materials (Sand, Gravel, Cement plaster, Grass, Formica and cast iron (original bed of channel)) in three conditions. Firstly the discharge was varied at same tail water level. Secondly the depths were varied for same discharge and thirdly the depths were measured for different discharges for each bed material Results were analyzed and were graphically presented .The Manning roughness coefficient was estimated for each bed material using the experimental and discharge optimization technique. The percentages of errors between the observed and predicted were reported. Since the channel represents compound case having glass wall and different bed material, the roughness coefficient of each bed materials were predicted by optimization on genetic algorithm to the lotter’s modified equation in which the exponent alpha value varies from 1.28 to 1.76 The shear stress distribution was examined by first and second approximation theory on smooth rectangular channel on Knight et al (1984) model. It was compared with the experimental average shear stress and was found the first approximation theory over estimated to the experimental value whereas second approximation result was within the average relative error of 1.61% for bed. Side wall/bed stress ration was found of 0.61. Similarly gradually varied flow was simulated in python using optimal value of roughness coefficient.

Identification of Pathogenic Bacteria in Traditional Packaged Donuts at Ampenan Market Using Xylose Lysine Deoxychoalate (XLD) Media

Snacks in traditional packaging are a type of food favored by the community. However, not a few buyers and sellers are not aware of the importance of cleanliness of these favorite foods from contamination with pathogenic bacteria that can cause illness for people who eat them. Many of them also do not know and are skilled at checking whether the food is clean from germs or not. This study aims to transfer knowledge and skills to identify bacteria in donuts in Ampenan Market using xylose lysine deoxychoalate (XLD) media. Samples of donut snacks in traditional packaging were taken from the Ampenan market in Mataram City and then examined for the content of pathogenic bacteria in the laboratory at The Mataram Laboratory Hall for Health, Testing and Calibration. The examination began with the isolation of bacteria from the sample on Selenit Broth Media in 24 hours incubation at 350C then continued with the isolation of Salmonella on selective agar media, namely XLD. The results of the isolation were examined and identified by Gram staining and bio-chemical assayt of control sugar and Salmonella suspect, oxidase and catalase tests. The results showed that Selenit Broth media could multiply and repair Salmonella cells and XLD media could separate it from other bacteria in the Gram stain. Gram stain, biochemical test, oxidase test and catalase test showed the presence of Gram negatif bacteria which was confirmed as Salmonella in the sample.

Comparison of Line Probe Assay (LPA) and Mycobacterium Growth Indicator Tubes (MGIT) Assay for Second-line TB Drug Susceptibility Testing

BACKGROUND: Tuberculosis (TB) infection is one of the most prominent health issues in the world, including in Indonesia. TB is evolving into multidrug-resistant tuberculosis (MDR-TB) and requiring second-line TB drugs. Mycobacterium growth indicator tube (MGIT) is the gold standard for susceptibility testing of second-line TB drugs. Alternatively, line probe assay (LPA), which detects genes resistant to second-line TB drugs, takes a shorter time to run. This study aims to compare MGIT and LPA's ability to detect TB resistance to second-line TB drugs and observe mutation patterns of genes encoding second-line TB drugs.METHODS: This was an observational analytic study, using cross-sectional method. The data were acquired from the MDR-TB clinic’s medical records at the Dr. Hasan Sadikin Hospital from September to December 2019. LPA and MGIT test were conducted at the Health Laboratory Hall of West Java Province, then tested using Kolmogorov-Smirnov and chi-square statistic.RESULTS: From 121 subjects, 113 people were not resistant to the second-line TB drugs, which was examined using both LPA and MGIT (93.4%), p=0.991. Mutations were found in gyrA and rrs gene. There was no significant difference between the proportion of subjects resistant to the second-line of TB drugs tested using LPA and MGIT.CONCLUSION: LPA is an alternative method to MGIT because it requires a shorter time and reduces the risk of exposure that will improve MDR-TB patients management.KEYWORDS: line probe assay (LPA), multidrug-resistant TB, mycobacterium growth indicator tube (MGIT), second-line TB drugs

Experimental Design of Physical Unconfined Aquifer for Evaluation of Well Abstraction Effects: Laboratory Approach

In unconfined aquifer water flows in both horizontal and vertical direction when pumping. So its study during pumping action is more complex. Soil type, porosity, hydraulic conductivity and transmissivity are important parameters that control the specific yield, drawdown and radius of influence on aquifer while abstraction. Due to large extraction of water from the aquifer, the water table drops down and may lead to permanent depletion of yield capacity of aquifer. For practical understanding of water being pumped from aquifer and its impacts on water storage the easiest method is experimental approach .So therefore, this study was planned to carry out the well abstraction from unconfined aquifer of homogeneous sandy soil designed as physical model on rainfall simulator at hydraulic laboratory hall of Campus itself. The catchment dimension is 2.2 meter length, 1 meter width and 0.15 meter depth with impermeable base filled with fine sand as per specification. The simulator was adjusted to make horizontal aquifer. The experimental observations were carried out in two conditions, first was well abstraction with no rainfall after saturation and the second is with rainfall even after saturation condition obtained. The two wells were operated for the abstraction of water simultaneously so that the effect of one well to another could be studied. After observation and data collection, for the analysis of hydraulic conductivity Dupit model. Empirical model and relative effective porosity model (REPM) were used for the comparative study. Similarly the radius of influence was estimated by three models (weber,Kusakin and Sichardt). For the estimation of transmissivity of the aquifer Thien model was used. Also the general equation (product of hydraulic conductivity and depth of aquifer) was used. Study showed the suitability of the available theories and governing equations for unconfined aquifer. The most important part of the study was to establish the correlation of drawdown and radius of influence with the time period of well abstraction. From the results the correlation coefficient for time and drawdown was of 90% and for time and radius of influence was 97%.

Spectroscopy of A=9 hyperlithium with the (e,e′K+) reaction

Missing mass spectroscopy with the $(e,e^{\prime}K^{+})$ reaction was performed at Jefferson Laboratory's Hall C for the neutron rich $\Lambda$ hypernucleus $^{9}_{\Lambda}{\rm Li}$. The ground state energy was obtained to be $B_{\Lambda}^{\rm g.s.}=8.84\pm0.17^{\rm stat.}\pm0.15^{\rm sys.}~{\rm MeV}$ by using shell model calculations of a cross section ratio and an energy separation of the spin doublet states ($3/2^{+}_1$ and $5/2^{+}_1$). In addition, peaks that are considered to be states of [$^{8}{\rm Li}(3^{+})\otimes s_{\Lambda}=3/2^{+}_{2}, 1/2^{+}$] and [$^{8}{\rm Li}(1^{+})\otimes s_{\Lambda}=5/2^{+}_{2}, 7/2^{+}$] were observed at $E_{\Lambda}({\rm no.~2})=1.74\pm0.27^{\rm stat.}\pm0.11^{\rm sys.}~{\rm MeV}$ and $E_{\Lambda}({\rm no.~3})=3.30\pm0.24^{\rm stat.}\pm0.11^{\rm sys.}~{\rm MeV}$, respectively. The $E_{\Lambda}({\rm no.~3})$ is larger than shell model predictions by a few hundred keV, and the difference would indicate that a ${\rm ^{5}He}+t$ structure is more developed for the $3^{+}$ state than those for the $2^{+}$ and $1^{+}$ states in a core nucleus $^{8}{\rm Li}$ as a cluster model calculation suggests.

Levels Pb (Lead) Content in The Thallus Lichens at Three Shade Tress in The Terminal Pinang Baris Medan, North Sumatera

This research aims to know the levels of Pb (Lead) on thalus lichens found on the three forest shade trees road in the area of Terminal Pinang Medan, North Sumatera. Type of this research is a descriptive exploratory survey method. Measurement of the levels of lead (Pb) using Furnace (destruction of dried) and Atomic Absorbance Spectrophotometer (AAS) in Medical Field Laboratory Hall. From the results of research conducted in the Terminal Area of Pinang Baris Medan, it is known that there are 12 different types of lichens. Results of the study known types of lichens that have levels of lead (Pb) is a type of most lichens Parmelia grabratula 49,01 mg/kg from Acacia trees (Acacia auriculiformis) I, and the lowest levels of lead (Pb) is a Palm tree from Buellia canescens 10,19 mg/kg III (Hyophorbe sp.).

PENGARUH PEMBERIAN RANSUM DENGAN DOSIS HERBAL YANG BERBEDA TERHADAP LEMAK DARAH AYAM PERSILANGAN

This study aimed to determine the effect of giving rations with different of herbs dosages on the blood lipid of crossbred chicken and to find out the best dosage of herbs in ration that affect the blood lipid of crossbred chicken. This research was conducted in 19 September 2018 to 26 September 2018 in the poultry house of the Integrated Field Laboratory, Faculty of Agriculture, University of Lampung. The examination of blood lipid levels was conducted at Lampung UPTD Laboratory Hall. The chickens used were crossbred chickens between male Lohman brown and female kampong (3/4 Lohman brown +1/4 kampong) layer phase (48 weeks) with total of 12 chickens. The experimental design used was completely randomized design (CRD) with 4 treatments and 3 replications. The treatment given were H0: without herbs, H1: 1g/kg herbs, H2 : 2g/kg herbs, and H3: 3g/kg herbs. The data obtained were analyzed using analysis of variance with significant level of 5%. The variables observed were consumption of rations, cholesterol, high density lipoprotein, and triglyceride content. The results showed that the rations with different herbs had no significant effect (P> 0.05) on the blood lipid levels of the crossbred chicken.
 Keywords: Rations, Herbs, Blood lipids, Crossbred chicken

Efektivitas Ekstrak Nanas (Ananas comosus(L.) pada Pertumbuhan Streptococcus beta-hemolitycus

<p><span>Prevalence of Group A <em>beta-hemolyticus Streptococcus</em> in the upper respiratory tract in healthy children is 10-35%, and at most high, in children aged 3-15 years Career <em>Streptococcus beta-hemolyticus</em> Group A can cause throat infections. The use of traditional medicine in the world is part of the history of human culture for thousands of years. One of the natural ingredients that can be used as traditional medicine is pineapple. The effectiveness of pineapple (<em>Ananas comosus (L</em>.) extract on the growth of <em>beta-hemolitycus Streptococcus</em> has been carried out. The purpose of this study was to determine the effectiveness of pineapple extract (<em>Ananas comosus (L.</em>) on the growth of <em>Streptococcus beta-hemolitycus</em>. This study was an experimental laboratory study) pure in vitro. In this study, the inhibitory and killing power of <em>Ananas comosus (L.</em>) extract against the growth of <em>Streptococcus β haemolyticus</em> at various concentrations of 0.5%; 1%; 2%; 4%; 8%; 10%; 20%; 30%; 40%; 50%; 60%; 70%; 80%; 90%; 100% .. The research was conducted at the Lampung Provincial Health Laboratory Hall conducted from June to November 2018. The results of the One-way Anova test obtained p-value=0,000 so that p-value<0.05 which means that the concentration of pineapple extract tested had an effect on growth of <em>Streptococcus beta hemolyticus</em> bacteria and the results of the Least Significant Difference (LSD) or Post hoc LSD (Least Significance Different) test (p-value<0,05) showed that pineapple extract was effective in inhibiting and killing germs of <em>Streptococcus β haemolyticus</em> at a concentration of 8%.</span></p>

Measurement of emissivity in student laboratories

Two alternative methods for measuring emissivity of opaque grey diffusive materials are presented. The first method is based on direct computations of emissivity in the form of a fraction consisting of three temperatures, namely the contact and contactless temperatures of the tested sample and the temperature of the laboratory hall envelope. The second method is based on the functional dependence between the contact and contactless temperatures of the measured sample. This dependence is fitted by a linear function. Fitting parameters provide the value of emissivity and the radiant temperature of the laboratory hall envelope. Both these methods seem to be convenient for student laboratory work.

Investigation into the ionization and acceleration regions shift in a Hall thruster channel

Location of the ionization and acceleration regions determines erosion belt location and thruster’s maximum throughput consequently. For Hall thrusters with wide throttle ratio the location of the ionization and acceleration regions in each operating mode could vary significantly, which makes it difficult to provide necessary throughput for multi-mode operation. In this article, the shift of the ionization and acceleration region location caused by the change of operating mode is studied with the help of numerical method. Numerical investigation was conducted with 1D3V hybrid-PIC simulations. According to the results, the ionization and acceleration regions could move upstream significantly with gas flow rate increase and magnetic field decrease. In addition, it was proved that an increase in the magnetic field gradient shifts the ionization and acceleration region location outside of the channel significantly. The trends obtained in numerical simulations were experimentally testified. The acceleration region trend validation was carried out with electrical probe measurements on a 1.5 kW laboratory Hall thruster. The ionization region shift was validated with the shift of the maximum light intensity of the xenon inside the channel of a 2.3 kW laboratory Hall thruster. Moreover, experimental investigations indicate that the ionization and acceleration regions could move significantly when oscillation mode changes.

Impact of Selected Environment Conditions on the Shrinkage Strains in Respect to Standard Recommendations

The article discusses the issues related to concrete shrinkage. The basic information on the phenomenon is presented as well as the factors that determine the shrinkage are described. Under laboratory conditions, these factors can be imposed and controlled, but in the field, it is not possible to maintain stable environmental conditions. The paper describes the experimental research that allows determining the effect of changes of humidity and ambient temperature on the values of shrinkage strains in concrete samples and verify the obtained results based on the theoretical model included in the Eurocode 2 standard. The shrinkage strains were measured on samples with dimensions 150x150x600 mm, made of C30/37 concrete with Portland cement and limestone aggregate and with water/cement ratio of 0.43. The samples were divided into two groups - the first group of samples was stored in a chamber with set and controlled values of temperature and humidity, and the second group was left in the laboratory hall with freely changing environmental conditions. The shrinkage strains were measured on samples in accordance with the ITB 194/98 for 175 days. A 20 cm base extensometer was used for the strain measurements. The studies of experimental results of the concrete shrinkage strain are presented with a comparative analysis of the results estimated by the guidelines of the standard according to PN-EN 1992-1-1:2008. The obtained results confirmed that the unstable humidity as well as temperature have a significant impact on the course of shrinkage strains in concrete and they both should be taken into consideration during performing concrete elements.

Sensitivity and Specificity of BMI and Abdominal Circumference as Indicators of Diabetes Risks

Background: Increased prevalence of obesity has an impact on increasing the risk of diabetes mellitus. BMI (Body Mass Index) and abdominal circumference are measure to assess a person including obesity or not and the best indicator in determining the risk of developing diabetes. Objective: This study aims to assess sensitivity and specificity of BMI and abdominal circumference as an indicator of diabetes risk and using Receiver Operator Characteristic Curve (ROC). Design: The design of this study was observational (cross sectional). The data used are secondary data from the results of research metabolic syndrome on adults at Health Laboratory Hall, West Sumatera Province in 2014, with 58 people. inclusion criteria aged 30-60 years, blood glucose examination and exclusion criteria of pregnant women. Results: Shows that the average of BMI are 25,18 kg/m 2 . The test of sensitivity and specificity of BMI as both an indicator of diabetes risk was > 25 kg/m 2 (Se 87% and Sp 76%) whereas, in both abdominal circumference as an indicator of diabetes risk was 90 cm in men and 80 in women (Se 91% Sp 58%). Analysis with ROC showed that the optimum sensitivity and specificity combination (> 0.8) was at 25.6 kg/m 2 BMI with Se 87% and Sp 83% for diabetes risk. Conclusions: abdominal circumference is better than BMI when used as an indicator of diabetes risk. Anthropometric measurements of height, weight and abdominal circumference can be done regularly and periodically to detect the occurrence of metabolic syndrome or the risk of diabetes.

The Design of Environmental Monitoring System Based on ARM and ZigBee

In this paper, an environmental monitoring system based on ARM and ZigBee is introduced in detail. The system is designed for a large scientific device. The whole monitoring system is divided into two parts. One part is above water and another part is in water. The above water monitoring part is to monitor the environmental parameters, including temperature (±0.5℃), humidity (±4.5%RH@25℃) and air pressure (500~1100mbar, ±1mbar) in the laboratory hall of the large scientific device. The underwater part is the temperature monitoring of the purification water, the accuracy of temperature measurement is better than 0.2℃ in the range of 10℃. All the data is uploaded to the terminal server through the network.

Tinjauan Keamanan Pangan Makanan Gorengan Berdasarkan Cemaran Kimia yang Dijual di Sepanjang Jalan Kaliurang Sleman Yogyakarta

Background : Food is a basic need for human growth, maintenance, health improvement. Safe food is free from biology and chemistry impurities, and other substances that are harmful for human health such as heavy metal contamination of lead (Pb) and zinc (Zn). Lead found at vehicle exhaust fumes and water can be a poison that damages the central nervous system. Although zinc is needed for the body, zinc can be toxic if it is over consumed. Zinc can be found in cooking utensils, water, and air. Foods sold on the roadside have great risksof impurities exposition of Pb and Zn, one of them is fried foods that are highly preferred by people.
 Objective : To find out the food safety of fried foods that are sold along Kaliurang street, Sleman, Yogyakarta based on chemical
 impurities of Pb and Zn
 Method.: This research was a descriptive observational with cross sectional study design. The data obtained were analyzed descriptively. The sample consists of 9 fried foods (it was known as tahuisi, fried tofu filled with vegetables) which were cooked on the street and exposed to 2 hours. The samples were raw tofu and fried tofu. This research was conducted at Health Laboratory Hall Yogyakarta quantitatively with AAS method.
 Results :100% of samples containing lead level between 0.1 to 0.6 mg/kg and zinc levels 12 to 15 mg/kg. The lead level of 77,7% of the sample ? the maximum level to consume, with 22.2% sample ? the maximum level to consume, that is 0.25 mg/kg. The lead level was increased from raw to fried tofu to after-2-hour-exposed tofu. The level of zinc in 100% of samples ? tolerable upper intake level (40 mg/kg).The difference of the zinc level in raw, fried, after a 2-hour exposed tofuwas caused by the use of water, the frying pan, and the condition of the contaminated air.
 Conclusion : The food safety of fried foods based on the lead impurities was 22.2% of the samples was safe to consume and 77,2% of the sample was not safe to consume, while based on the impurities of zinc, 100% of the sample was safe to consume.
 

Tinjauan Keamanan Pangan Makanan Gorengan Berdasarkan Cemaran Kimia yang Dijual di Sepanjang Jalan Kaliurang Sleman Yogyakarta

Background : Food is a basic need for human growth, maintenance, health improvement. Safe food is free from biology and chemistry impurities, and other substances that are harmful for human health such as heavy metal contamination of lead (Pb) and zinc (Zn). Lead found at vehicle exhaust fumes and water can be a poison that damages the central nervous system. Although zinc is needed for the body, zinc can be toxic if it is over consumed. Zinc can be found in cooking utensils, water, and air. Foods sold on the roadside have great risksof impurities exposition of Pb and Zn, one of them is fried foods that are highly preferred by people.
 Objective : To find out the food safety of fried foods that are sold along Kaliurang street, Sleman, Yogyakarta based on chemical
 impurities of Pb and Zn
 Method.: This research was a descriptive observational with cross sectional study design. The data obtained were analyzed descriptively. The sample consists of 9 fried foods (it was known as tahuisi, fried tofu filled with vegetables) which were cooked on the street and exposed to 2 hours. The samples were raw tofu and fried tofu. This research was conducted at Health Laboratory Hall Yogyakarta quantitatively with AAS method.
 Results :100% of samples containing lead level between 0.1 to 0.6 mg/kg and zinc levels 12 to 15 mg/kg. The lead level of 77,7% of the sample ≥ the maximum level to consume, with 22.2% sample ≤ the maximum level to consume, that is 0.25 mg/kg. The lead level was increased from raw to fried tofu to after-2-hour-exposed tofu. The level of zinc in 100% of samples ≤ tolerable upper intake level (40 mg/kg).The difference of the zinc level in raw, fried, after a 2-hour exposed tofuwas caused by the use of water, the frying pan, and the condition of the contaminated air.
 Conclusion : The food safety of fried foods based on the lead impurities was 22.2% of the samples was safe to consume and 77,2% of the sample was not safe to consume, while based on the impurities of zinc, 100% of the sample was safe to consume.
 
 Keywords. Fried food, food safety, lead (Pb) level, zinc (Zn) level.

Numerical Investigation of Plasma Sheath Under Multiple Oscillations in Acceleration Region of Hall Thrusters

Oscillations range from KHz-GHz have been measured in the experimental measurements within the laboratory Hall thruster. With the various frequency oscillations, different kinds of collisions between particles and the complex electromagnetic field environment, the dynamics of particles in the discharge chamber are really intricate. The dynamics of particles become even untraceable in the near-wall region where the plasma sheath exists. In this study, the two-dimensional fully kinetic Immersed Finite Element Particle-In-Cell (IFE-PIC) numerical models are developed in the axial-radial (z-r) plane at the acceleration region, with the intent of examining the effects of multiple oscillations on the plasma sheath. The results are valuable for understanding the features of plasma sheath in acceleration region at the real working conditions.