Port Sample Research Articles

Microwave heating of coal slime based on multi-physics field simulations: Regulating waveguide port size and sample radius to improve microwave utilization efficiency

Microwave pyrolysis, a promising green-processing technology with high efficiency and low consumption, is particularly applicable in the pyrolysis of solid waste fuels such as coal slime. The microwave thermal effect plays an imperative role in the pyrolysis process. Low microwave utilization efficiency in single-mode microwave cavities is caused by the irregular field intensity distribution, and since of the high manufacturing costs of the equipment, it is unclear the relationship between waveguide port size, microwave field intensity distribution, and the temperature of sample. In this study, the effects of different waveguide port sizes and sample radius on the heating characteristics of coal slime were investigated using COMSOL Multiphysics software to construct a coupled multiphysics finite-element model. Moreover, the effects of the radius of the coal slime on the microwave utilization efficiency. The results demonstrated that only two types of wave distribution were found within the cavity, α and β, under the size of the waveguide port. The field intensity distribution in the β-type cavity was uniform, which prompted the sample temperature from 176 °C to 657 °C and microwave utilization efficiency from 10.16 % to 33.87 %. The maximum microwave utilization efficiency was increased from 33.87 % to 67.22 % by adjusting the radius of the sample at the optimal port size. The efficiency of the microwaves was maximized when the width-to-height ratio of the waveguide is 70:65 and the sample radius is 30–35 mm, and the sample temperature was maintained in a more desirable range. From the findings of this study, both the waveguide port size and sample radius are essential influencing factors in determining the sample temperature and microwave energy utilization efficiency during the heating of coal slime.

Behavior and fate of a novel neonicotinoid cycloxaprid in water–sediment systems through position-specific C-14 labeling

Neonicotinoid insecticides are ubiquitous worldwide, are problematic for pollinators and other nontarget creatures and affect the stability of the environment. These negative impacts prompt the ongoing development of alternatives. Cycloxaprid, a novel cis-nitromethylene neonicotinoid, exhibits high efficacy against imidacloprid-resistant pests and is viewed as a promising alternative candidate. However, information about the fate of cycloxaprid in water–sediment systems is limited. To bridge this knowledge gap, radioactive isotope-labeled 14C-cycloxaprid was employed to determine the formation of residues, transformation products, and degradation pathways. First, the mass balance analysis of residue was investigated. The extractable residue of cycloxaprid accounted for 100–40% of the total radioactive residue; cycloxaprid could transform into bound residue (0–54%) and mineralization (0–0.015%). It was partitioned from the water phase to sediments with dissipation half-lives of 6.62 d in the Dianshan Lake sample and 4.61 d in the Jinhui Port sample. Three degradation products were then detected and identified by liquid chromatography coupled to mass spectrometry. Its main metabolite, 2-chloro-5-[(2-(nitromethylene)-1-imidazolidinyl)methyl]pyridine, was more toxic than the parent compound and should be given priority in monitoring. Ring opening, carboxylation, and reduction of nitro groups were confirmed as the primary degradation pathways. The present study assessed the fate of cycloxaprid in two different water–sediment systems for the first time, and this information could provide insight into the potential ecological impacts of cycloxaprid and more precisely into evaluating its environmental risks in the future.

Analysis of port efficiency using imprecise and incomplete data

Port efficiency assessments based on data envelopment analysis (DEA) usually assume that the inputs-outputs are measured using known and crisp data values. However, the data accuracy, the imprecision, and the missing values are common problems in many port efficiency assessment applications, particularly when the data are drawn from various heterogeneous sources. In those cases, common practice so far was to use either approximated values or to completely exclude these ports from the analysis. This paper proposes Imprecise DEA (IDEA) to assess the efficiency of ports when imprecise and missing data appear in a port assessment problem. In this approach, the missing or imprecise data are replaced by interval or ordinal data, properly estimated using auxiliary data. In a post-DEA analysis stage an iterative procedure is developed with the purpose of estimating new interval bounds that turn non-efficient ports into efficient. This methodology is put into practice through an application that assesses the efficiency of a port sample with missing and imprecise data in the year of reference.

Male color phase in gag: implications for monitoring sex ratio via visual underwater surveys and port sample observations

Male color phase in gag: implications for monitoring sex ratio via visual underwater surveys and port sample observations

Injection-port derivatization coupled to GC–MS/MS for the analysis of glycosylated and non-glycosylated polyphenols in fruit samples

Polyphenols, including glycosylated polyphenols, were analyzed via a procedure based on injection-port derivatization coupled to gas chromatography–tandem mass spectrometry (GC–MS/MS). The polyphenols in lyophilized fruit samples were extracted with an acidified MeOH mixture assisted by ultrasound. Samples were dried under vacuum, and carbonyl groups were protected with methoxylamine. Free hydroxyl groups were subsequently silylated in-port. Mass fragmentations of 17 polyphenol and glycosylated polyphenol standards were examined using Multiple Reaction Monitoring (MRM) as the acquisition mode. Furthermore, in-port derivatization was optimized in terms of optimal injection port temperature, derivatization time and sample: N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) volume ratio. A C18 solid-phase-extraction clean-up method was used to reduce matrix effects and injection liner degradation. Using this clean-up method, recoveries for samples spiked at 1 and 10μg/g ranged from 52% to 98%, depending on the chemical compound. Finally, the method was applied to real fruit samples containing the target compounds. The complete chromatographic runtime was 15min, which is faster than reported for recent HPLC methods able to analyze similar compounds.

Male color phase in gag: implications for monitoring sex ratio via visual underwater surveys and port sample observations

Fishing of gag (Mycteroperca microlepis Goode and Bean, 1879) spawning aggregations in the northern Gulf of Mexico has reduced the percentage of males in the population from approximately 17% to 2% since the 1970s. This is critical as gag are monandric, protogynous hermaphrodites, and accurate estimation of size-at-transition and sex ratio is necessary for proper management. Presence of darkened pigmentation on the abdomen was thought to indicate transition from female to male, and thus, video observations of gag with dark pigmentation were used to estimate sex ratios and indices of abundance. Recent video observations of gag demonstrate that they can change pigmentation patterns within seconds, which could be leading to misidentification of males in those surveys. Results of our investigation showed that males observed in the video survey, as determined by pigmentation only, are significantly shorter than males observed in the commercial fishery, which were determined using both pigmentation and histological examination. Significant differences were detected between pigmented and non-pigmented gag in the commercial data, but not in the video survey data. Additionally, size at which 50% of females had transitioned to male was significantly larger when estimated using commercial fishery data vs the video survey data. Due to significant differences in length distributions and estimates of size-at-transition, and evidence of rapid changes in pigmentation patterns, it is inadvisable to estimate sex ratios or relative indices of abundance by sex for gag from video observations. To address potential shifts in size- and age-at-transition, continued monitoring of sex ratios using histological techniques is recommended.

Analysis of chemical forms of heavy metals in contaminated soil by sequential extraction methods

The samples collected from soils and sediments near the mouth of a river (samples A, B, and C), port (sample D), or shooting range (samples E and F) were investigated with Tessier's sequential extraction method to design the remediation process for contaminated sites. This method was chosen to determine the chemical forms of heavy metal contaminants, which consists of five fractions such as ‘exchangeable’, ‘bound to carbonate’, ‘bound to oxide’, ‘bound to organic matter’, and ‘residue’. In the case of samples from sediments near the mouth of a river, zinc (Zn) distributes in the fractions ‘bound to oxide’ and ‘bound to organic matter’, while copper is observed in the fractions ‘bound to organic matter’ and ‘residue’, respectively. When the sample obtained from the sediment near a port was examined, most of Zn distributes in the fractions ‘bound to organic matter’ and ‘residue’. In sites E and F, lead, Zn, and copper distributed in the fractions ‘bound to carbonate’ and ‘bound to oxide’. On the basis of results, physical treatment followed by chemical leaching for sites A, B, and C, physical separation process for site D, and chemical treatment process for sites E and F would be required to remediate the contaminated sites.

Efficacy of decontamination and sterilization of a single-use single-incision laparoscopic surgery port

To determine the efficacy of decontamination and sterilization of a disposable port intended for use during single-incision laparoscopy. 5 material samples obtained from each of 3 laparoscopic surgery ports. Ports were assigned to undergo decontamination and ethylene oxide sterilization without bacterial inoculation (negative control port), with bacterial inoculation (Staphylococcus aureus, Escherichia coli, and Mycobacterium fortuitum) and without decontamination and sterilization (positive control port), or with bacterial inoculation followed by decontamination and ethylene oxide sterilization (treated port). Each port underwent testing 5 times; during each time, a sample of the foam portion of each port was obtained and bacteriologic culture testing was performed. Bacteriologic culture scores were determined for each port sample. None of the treated port samples had positive bacteriologic culture results. All 5 positive control port samples had positive bacteriologic culture results. One negative control port sample had positive bacteriologic culture results; a spore-forming Bacillus sp organism was cultured from that port sample, which was thought to be an environmental contaminant. Bacteriologic culture scores for the treated port samples were significantly lower than those for the positive control port samples. Bacteriologic culture scores for the treated port samples were not significantly different from those for negative control port samples. Results of this study indicated standard procedures for decontamination and sterilization of a single-use port intended for use during singleincision laparoscopic surgery were effective for elimination of inoculated bacteria. Reuse of this port may be safe for laparoscopic surgery of animals.

MEASUREMENT OF ELECTRICAL CHARACTERISTICS OF FEMALE BREAST TISSUES FOR THE DEVELOPMENT OF THE BREAST CANCER DETECTOR

In this paper, dielectric characteristics of female breast tissues were measured. Breast Tissues were mainly composed of fat, flbro-glandular and tumor. Measured tissues were directly extracted from mice and a rat just before the measurements to maintain the tissues as fresh as living ones before degeneration. This makes the measured results more accurate. Because the extracted tissues were very thin, they were measured by two methods using HP probe and a newly designed two-port sample holder. Numerical results for the two- port sample holder were obtained for both the forward and inverse problems. Dielectric properties of breast tissues were measured in the frequency range between 50MHz and 5GHz. We calculated the electrical constant with the measured data from the two-port sample holder. As a result of the measurement, the dispersion characteristics of the female breast tissues were fltted into the flrst Cole-Cole model.

한국 근해 쌍끌이대형저인망어업의 어종군집 분석

The fishing grounds of Korean large-pair trawlers have shifted since exclusive economic zones (EEZs) were established in a fisheries agreement involving countries neighboring Korean waters. The distributions of marine ecosystems and fisheries resources have been changing with environmental changes such as global warming and with the shift in species targeted as a result of changes in fishing technology and fishing gear. This study analyzed variation in the species assemblages caught in Korean waters by large-pair trawlers as a result of these geopolitical and environmental changes. The data used in this study were obtained from the Fishery Production Statistics of Korea and the Port Sample Survey of the National Fisheries Research and Development Institute (NFRDI) from 1990 to 2007. Hierarchical clustering analysis (HCA) and correspondence analysis (CA) were used to explore the characteristics of the catch-species composition. The overall variation in the species composition of the catch of Korean large-pair trawlers showed that the proportions of croaker Johnius grypotus, small yellow croaker Larimichthys polyactis, eel Anguilla japonica, and blue crab Portunus trituberculatus decreased, whereas those of hairtail Trichiurus lepturus, Spanish mackerel Scomberomorus niphonius, anchovy Engraulis japonicus, and common squid Todarodes pacificus increased in Korean waters over the 18-year period. The results of the HCA of the annual catch data by species showed four different distributions of fish species according to year. Results of the CA showed that the species assemblages differed between the 1990s and 2000s.

A Reliable and Safe Method of Collecting Blood Samples from Implantable Central Venous Catheters for Determination of Plasma Gentamicin Concentrations

To evaluate the extent of agreement between plasma gentamicin concentrations determined from samples collected by using implantable subcutaneous central venous catheters (ports) with the push-pull method and those collected by finger lancet punctures in children with febrile neutropenia. Prospective, randomized study. University-affiliated, tertiary care hospital. Sixty-two children with cancer who had single- or double-lumen ports and who received gentamicin for treatment of febrile neutropenia between February 2008 and October 2009. One blood sample was collected from the port by using the push-pull method at the same time one blood sample was collected by finger lancet puncture for determination of plasma gentamicin concentrations. Forty-four pairs of samples were available for assessment of agreement, and 43 were available for pharmacokinetic analysis. Agreement between plasma gentamicin concentrations determined from blood samples from ports and finger lancet punctures was assessed by the intraclass correlation coefficient (ICC), Bland-Altman analysis, and comparison of simulated dosage adjustments. Changes in port patency were monitored for 1 week after port sampling. Differences in simulated dosage adjustments calculated by using either the port or finger lancet puncture samples that differed by greater than 20% were considered clinically significant. Agreement between the 44 finger lancet puncture and port sample pairs was excellent (ICC 0.991, 95% confidence interval 0.984-0.995). Port plasma gentamicin concentrations were 4.7% lower than those concentrations determined in blood from finger lancet punctures. The observed limits of agreement ranged from -20.5% to 11%. Differences in dosage adjustments calculated by using port and finger lancet puncture plasma gentamicin concentrations were not clinically significant in 38 (88%) of 43 cases. No changes in port patency were observed in the week after port sampling. The push-pull method of blood sampling is a reliable and safe option for determining plasma gentamicin concentrations in children with ports.

Reconstruction Technology on the Surface of Engine Port Based on Reverse Engineering

Applying reverse engineering technology to the design of engine port, the reconstruction technology on the free-form surfaces of the engine port were investigated deeply. The data on the 3D surfaces of the engine port sample were collected by means of laser scanner, and the scattered data points were processed in regularization. Triangulation processing of surface data cloud was carried out based on surface grid method. According to the free-form surface technology and curve fitting algorithm used at present, the methods used to reconstruct the port surface were proposed. Taking CATIA software as developing platform, the free-form surfaces of the engine port were reconstructed.

Evaluation of a small mechanical and pneumatic bladder pump for water quality sampling

AbstractTwo small‐diameter (≤0.5‐inch/13‐mm O.D.) bladder pumps were evaluated under the U.S. EPA Environmental Technology Verification Program to assess their ability to provide representative water quality samples for several volatile organic compounds (VOCs) and major element cations. Both a pneumatic bladder pump (PnBP) and a newly designed mechanical bladder pump (MBP) were evaluated. Since the MBP does not require compressed air to operate, the field logistics are simplified and cost of conducting low‐flow sampling can be reduced. Replicate samples were collected from an above‐ground standpipe spiked with selected VOCs and cations. Low‐flow sampling protocol was followed during collection of replicate samples from six direct push (DP)–installed monitoring wells at Tyndall Air Force Base, Florida. Simple statistical methods are used to evaluate the sample quality provided by the pumps as compared to reference samples. F‐tests are used to evaluate pump sample precision, and t‐tests are applied to evaluate comparability of the pump sample results to the colocated reference or port sample results. Statistical analysis reveals that the samples collected with the pumps provide precision comparable to that observed in the reference samples. Significantly greater variability was observed between the pump and reference samples collected from the DP wells than was observed during the standpipe trials. The results and statistics from the trials at the standpipe indicate that both the PnBP and MBP provide water quality samples that are comparable to the reference samples, for the analytes investigated.

GIT (Glucose Infusion Test): Polycentric Evaluation of a New Test for Vascular Access Recirculation

Introduction. Vascular access recirculation (AR), which is often unacknowledged, remains an important cause of inadequate dialytic dose. The glucose infusion test (GIT) is a new method for detecting and quantifying AR. This paper reports on a polycentric evaluation of the new test and a comparison with the classical Urea-test (UT). Methods. GIT protocol comprises withdrawal from the arterial port (sample A), injection into the venous drip chamber of 1 g glucose in 4 seconds, withdrawal from the arterial port (sample B) continuously from 13 to 17 seconds. Glucose is determined on A and B by a reflectance photometer. If B = A then there is no recirculation. If B exceeds A by at least 20 mg/dl there is recirculation. AR quantification: AR% = (B-A) / 20. GIT was performed on 623 patients from eleven dialysis centers to screen the patients for AR. Subsequently, GIT and Urea-test (UT) were compared in 189 paired tests. The reproducibility of GIT and UT was studied in 28 paired tests performed in sequence. Results. The screening test by GIT was positive in 68 cases (11 %). The majority of positivities was found in central venous catheters (CVC, 27/50 cases, 54 %), whereas only 7 % of artero-venous fistulas (AVF) were positive. In the CVC group, Tesio catheters were more frequently positive compared to Dual Lumen Catheters (64 % vs. 29 %). The comparison GIT - UT showed that results matched in 162 tests (79 negative and 83 positive both by GIT and UT), showing that on the grounds of UT, GIT has high sensitivity and specificity. In 27 tests GIT was positive, but UT negative. This disagreement is due to the different minimal limit of detection, 1 % for GIT and 5% for UT. The reproducibility was greater with GIT than with UT with a lower D% (respectively -0.6 +/- 2.5 and -0.4 +/- 6.1 %, p<0.001) and a lower coefficient of variation (17 vs 33 %). Conclusions. The screening of 623 patients by GIT confirmed that AR in AVF is normally absent, whereas an un-expectedly high frequency of moderate AR in CVC was found. The GIT-UT comparison showed that the new test is simple and immediate, and gives results with higher accuracy, sensitivity and reproducibility than UT.

Pre-column derivatization of sulfa drugs with fluorescamine and high-performance liquid chromatographic determination at their residual levels in meat and meat products

A rapid, sensitive and selective high-performance liquid chromatographic method is described for simultaneous determination of eight sulfa drugs in meat and meat products using pre-column derivatization with fluorescamine. The drugs are sulfisomidine, sulfadiazine, sulfamerazine, sulfadimidine, sulfamonomethoxine, sulfamethoxazole, sulfadimethoxine and sulfaquinoxaline. The method includes blender extraction of 3-g samples with choloroform, partition with 3 M hydrochloric acid, derivatization with fluorescamine at pH 3.0 and subsequent high-performance liquid chromatographic analysis on a C 18 column with fluorescence detection at an excitation wavelength of 405 nm and an emission wavelength of 495 nm. The drugs were separated with a mobile phase of acetonitrile-2% acetic acid (3:5) at 55°C. The average recovery from samples fortified at 0.1 ng/g was 92.6% with a coefficient of variation of 6.2%. The detection limit was 0.01 ng/g for sulfaquinoxaline and 0.005 ng/g for the other seven drugs. The method was field-tested in a survey of 37 samples including beef (five), pork (seven), chicken (seven), ham (five), sausage (eight), bacon (two) and roast beef (three). Sulfadimidine was detected in one port sample at the level of 0.295 ng/g and in ham at 0.178 ng/g.

High-performance liquid chromatographic analysis of glycosphingolipids and phospholipids.

The modern form of liquid chromatography commonly referred to as high-speed or high-performance liquid chromatography (HPLC) has developed very rapidly in the past few years. HPLC implies the use of reusable columns, injection port sample application, the use of pumps for uniform solvent flow at high-pressure if necessary and automatic sample detection. Since 1696–1970 a better understanding of the factors which improve the speed and resolution in liquid chromatography has evolved. New column packing materials, column packing techniques, high pressure — low volume equipment and highly sensitive detectors have been developed. A large variety of such columns and equipment are now available commercially. The modern HPLC techniques have led to the development of sensitive, quantitative methods, analogous to that available for volatile materials by gas-chromatography, for a very large variety of relatively high molecular weight substances of biological interest.