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To compare detection rates of NET liver metastases of MRI and Ga-68-DOTATATE PET/CT to provide more clarity when selecting diagnostic imaging tests for NET staging. In this IRB-approved single-institution retrospective study, all patients with pathology-proven NET who underwent Ga-68-DOTATATE and MRI scans within 8 weeks of each other (3/2017–2/2020) were reviewed. Number of metastases for each patient on diffusion-weighted imaging (DWI), dynamic contrast-enhanced (DCE) MRI, and Ga-68 DOTATATE were recorded by two blinded radiologists, followed by consensus review with two separate blinded readers for MRI and nuclear medicine. Per-lesion and -modality scoring at each lesion location were then performed in consensus. Per-patient linear regression was performed comparing MRI and Ga-68 DOTATATE detection rates for each reader and in consensus, and per-lesion-matched pair difference means were used to compare detection frequency between modalities. 32 patients (mean age 59 years, 59.4% male) and 90 liver metastases were analyzed. Intraclass coefficients (ICC) [95% CI] between the two readers were 0.97 [0.95, 0.99], 0.89 [0.82, 0.94], and 0.98 [0.97, 0.99] for Ga-68 DOTATATE, DWI, and DCE, respectively. Matched per-lesion mean differences were + 0.17 ± 0.07 (p = 0.01) and + 0.22 ± 0.06 (p =

The aroma characteristics of Pu-erh tea were studied in this work. A total of 117 volatile compounds were identified by HS-SPME combined with GC–TOF/MS, of which 29 active aroma compounds were identified by olfactometry. The active aroma compounds of Pu-erh tea were analyzed by intensity aroma (IA), aroma extraction dilution (AEDA), sensory quantification value (MF), detection frequency (DFA) and odor activity value (OAV). 24, 21 and 23 active aroma components were identified by DFA, AEDA and OAV, while 20 by IA and MF. Recombination of the obtained active aroma components indicated that OAV method was best for determining the active aroma compounds as the aroma profile of OAV recombination model was the most similar to that of Pu-erh tea sample. Omission test of the OAV recombination model furtherly identified 19 characteristic active aroma compounds of Pu-erh tea, and linalool, 1,2,3-trimenthoxybenzebe, 1,2,4-trimethoxybenzene and ɑ-ionone were the key characteristic active aromatic compounds.

Per- and polyfluoroalkyl substances (PFASs) are persistent and bio-accumulative substances that have many adverse effects on human bodies. This study investigated the PFASs distribution characteristics in urine samples of workers from an acrylic fiber plant and a chemical plant. It was found that perfluorobutanoic acid (PFBA) was the predominant PFASs both in urine samples from the chemical plant (detection frequency: 86.52%; median value: 39.01 ng/mL) and the acrylic fiber plant (detection frequency: 88.16%; median value: 44.36 ng/mL). Meanwhile, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) were detected with very low frequencies and low concentrations. Furthermore, the results showed that PFASs levels in urine samples of workers from different units of the plants were quite different. PFASs concentrations of urine samples in males were higher than those in females, especially for PFBA, PFHxA, and PFDoA. The age had limited effects on the PFASs distribution in urine samples in this study, as short-chain PFASs were the dominant compounds. The correlations between PFASs concentrations in urine and gender/ages of workers were finally analyzed by Person correlation. The overall results may indicate that short-chain PFASs (such as: PFBA and PFBS) were becoming dominant for human exposure, especially occupational workers.

The phthalate concentrations in dust from undergraduate dormitories, classrooms, and homes in Beijing, China, were measured in April 2017. We analyzed the characteristics of phthalates in dust from three environments. In addition, we estimated the daily intake of phthalates via three pathways using Monte Carlo simulations. The detection frequency of eight phthalates in dust ranges from 74.5 to 100%. Di (2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DnBP), and di-isobutyl phthalate (DiBP) are the most abundant phthalates. The median proportion of DEHP in dust is the highest, ranging from 67.1 to 72.9%. The PMF results indicated that two, four, and three types of phthalate sources exist in home, dormitory, and classroom, respectively. The differences in the phthalate concentrations between sunny and shaded rooms and urban and suburban classrooms are insignificant, whereas that between male and female dormitories is significant. The total daily intake of DEHP, DnBP, and DiBP ranges from 97.3 to 336 ng/ (kg·day). The oral intake for DEHP in classrooms and the dermal intake of DnBP and DiBP in homes are the highest. The carcinogenic risk of DEHP to university students is the highest in classrooms and the total carcinogenic risk of the three environments is 4.70 × 10-6.

The mycotoxins aflatoxin B1 (AFB1) and deoxynivalenol (DON) are found worldwide in crops and dietary staples. The prevalence and levels of these contaminants can vary greatly, and data in Bangladeshi food commodities are scarce. To characterize human exposure, we have conducted biomonitoring, analyzing AFM1 (a metabolite of AFB1) and DON levels in urines of adult cohorts in Bangladesh. Yet, AFM1 and DON occurrence has not been studied in the very young population of this country. Thus, the same methods, HPLC-FD for AFM1 and LC–MS/MS for DON analysis, were now applied to determine these biomarkers in urines of infants (n = 49) and young children (n = 105) in Rajshahi and Dhaka district. Overall, AFM1 and DON detection frequency was 43.5% and 33.4%, with 34.7% and 11.5% in infant and 47.6% and 39.4% in children urines, respectively. The mean AFM1 levels in all infants (9.1 ± 14.3, max 55.6 pg/mL) and children (8.8 ± 12.9, max 75.3 pg/mL) were not significantly different. The AFM1 mean level was slightly higher in Dhaka (9.4 ± 12.4) compared to Rajshahi (8.5 ± 13.9 pg/mL) district. The average DON level was about 2-fold higher in infant (3.8 ± 2.9, max 6.8 ng/mL) than children urines (1.6 ± 1.8, max 8.6 ng/mL), and higher in Rajshahi (2.1 ± 2.3 ng/mL) than Dhaka (1.4 ± 1.6 ng/mL) district. The biomarker-based estimated average daily DON intake (29.6 ± 108.3 ng/kg bw in infants and 36.4 ± 81.8 ng/kg bw in children) or the maximum exposure (560 ng/kg bw) do not exceed the current maximum provisional tolerable daily intake value of 1 µg/kg bw for DON, although DON exposure in infants and children is higher than that of Bangladeshi adults. The AFM1 urine levels in young children are somewhat lower than those found previously in adult cohorts in Bangladesh, but the frequent detection of this biomarker for AFB1 exposure raises further concerns, also for this vulnerable part of the population. Therefore, continuous surveillance for aflatoxins in Bangladeshi food commodities is clearly required, first to identify major sources of intake and then to reduce exposure.

The impact of industrial activities on atmospheric volatile organic compounds (VOCs) in the Sihwa-Banwol complexes, i.e., the largest industrial area in Korea, was investigated. More than 60 VOCs were determined from 850 samples collected from four sites in and around the complexes through a 2-year monitoring campaign from 2005 to 2007. The VOCs of particular concern found in the area were benzene, toluene, ethylbenzene, xylenes, trichloroethylene, and formaldehyde, given their toxicity, concentration, and detection frequency. Toluene was the most abundant one. The VOC concentration rankings were consistent with their emission rankings. Most VOCs had higher concentrations at the industrial sites than at residential sites, indicating a significant impact of industrial emissions. The ambient levels of benzene and formaldehyde were additionally affected by vehicular emissions and secondary formation, respectively. Overall, the VOC levels increased in winter and at night, because of the local weather conditions. In contrast, the formaldehyde concentration increased in summer, owing to its secondary formation in the atmosphere. The ambient VOC levels in Sihwa-Banwol were higher than those in other parts of Korea. Additionally, the cumulative cancer risks posed by the toxic VOCs exceeded a tolerable risk level of 1 × 10−4 in not only the industrial areas but also the residential areas. The sum of the non-cancer risks in both areas significantly exceeded the threshold criterion of 1. The large amounts of aromatic compounds emitted from the industrial complexes are believed to play a crucial role in the elevated levels of surface ozone in the Seoul metropolitan area during the summer season. Therefore, comprehensive measures for controlling the VOC emissions in the Sihwa-Banwol area need to be prioritized to reduce the health risks for residents of not only this area but also the capital Seoul and its surrounding areas.

Hepatitis E virus (HEV) is the causative agent of acute hepatitis E. Genotype 3 (G3) and 4 (G4) HEV have recently been identified in and isolated from swine as the main HEV genotypes worldwide. However, there is limited information on HEV infection status among pigs in Taiwan, especially pigs in the stage before transportation to the slaughterhouse. To determine the frequency of HEV infection among pigs in Taiwan, we detected and quantified HEV RNA contained in 295 fecal specimens collected from 6-month-old pigs bred in 30 pig farms located in 8 counties. We found that 25.1% (74/295) of the fecal specimens were positive for HEV RNA by a quantitative real-time reverse transcription-polymerase chain reaction, and the copy number ranged from 2.3 × 103 to 2.08 × 107 copies/g. Amplification of a 338 bp sequence in ORF2 was achieved in 16 of 74 HEV RNA-positive samples, and their nucleotide sequences were determined. Two HEV sequences appeared to belong to subtype 3a of G3 and the remaining 14 HEV sequences belonged to subtype 4b of G4 (G4b). The entire genome sequence of two G4b HEVs was obtained by next-generation sequence analyses, and the phylogenetic analyses indicated that unique G4b HEVs were circulating in pig farms in Taiwan. In the present study, we found that both G3 and G4 HEVs were circulating in Taiwanese pig farms and G4b was the predominant subtype. In addition, the relatively high detection frequency of HEV RNA in the 6-month-old pigs indicated that Taiwanese pigs just before transportation to the slaughterhouse are at risk of carrying HEVs, and thus thorough cooking or heating of pork meat or organs is needed before consumption in Taiwan and possibly in other countries as well.

We develop three methods for the joint symbol detection, frequency offset and channel estimation in time-varying multiple-input multiple-output channels with multiple frequency offsets between transmit and receive antennas. These methods are based on particle filtering. The first method utilizes the posterior proposal distribution (PD) to generate particles, which is optimal PD because it minimizes the variance of the importance weights, conditionally on the observations and past particles. Second, we develop an improved sampling strategy, which exploits the discrete nature of the symbol variable. The improved sampling strategy has same computational complexity as the posterior PD, while its performance is significantly improved. Finally, we derive a suboptimal complexity-reduced method, which utilizes the artificial sequential structure of the Bell-Labs layered space–time detection scheme to compress the sample space of symbol variable. Compared to the posterior PD, the computational complexity of the suboptimal method is largely reduced, while it still significantly outperforms the posterior PD. Simulation results are provided to illustrate the performance of these methods.

Risk assessment methodology for chemicals in Shenyang Chemical Industrial Park (SCIP) was established from the realities of frequent environmental pollution emergencies, just for the sake of quantitatively describing the risk levels of the chemicals, and for conducting priority control for those typical ones among them. Meanwhile vapor pressure (PV), median lethal concentration (LC50), combustibility and explosibility (CE), popularity (P) and detection frequency (DF) are selected as the risk assessment index for the chemicals, and then the weight from each assessment indicator on the surveillance levels for those chemicals has been identified. Finally, Fuzzy Comprehensive Evaluation (FCE) was adopted to work out the surveillance assessment level for each chemical in SCIP. The results show that 14 chemicals with relatively high-risk levels have been identified based on the above methods. Study on the risk assessment methodology for SCIP shall avail judgment on the risk levels for chemicals, allowing better management and control for chemicals accordingly.

Polychlorinated biphenyl (PCB) concentrations in surface soil samples (0-10 cm) from 23 city parks (8 urban and 15 suburban) from Xi'an, China were presented. The average concentration of Σ7 PCBs among all the sites was 1.68 ng g(-1) dry weight. High detection frequency (100 %) of PCB 28 and PCB 52 suggested wide occurrence of PCB contaminations in Xi'an. Among these PCBs, PCB 28, 52 and 153 were the most dominant compounds (14.9 %, 39.3 % and 9.5 % of the Σ7 PCBs on average, respectively). "Urban fractionation effect" was found in Xi'An. In other words, PCB concentrations were higher in the urban city park soils than those in suburban park soils. The PCB contamination in Xi'an city park soils were at a low level based on the Dutch guideline. However, dioxin-like PCB congeners were detected from 12 parks, which indicated further investigation was urgently required in future. Furthermore, total PCB concentrations were used to evaluate the cancer risk via ingestion, dermal and inhalation and the results showed that the total cancer risk was at the very low level in this area.

Odor-active compounds are commonly analyzed using gas chromatography–olfactometry (GC–O). However, there are only limited guidelines available for panelist training with this technique. In the current study, 29 volunteers were trained to detect, describe, and rate the intensity of odors. In addition, three GC–O methods, i.e., aroma extraction dilution method, detection frequency, and posterior intensity (PI), were used to evaluate the newly trained panelists’ ability to analyze key compounds of kvass (fermented nonalcoholic drink) aroma. A five-step approach is proposed for training as follows: (1) introduction of the method; (2) vocabulary training using standard compounds and learning the use of the scale; (3) training with the reference mixture A; (4) training with the real product of interest—the beverage kvass; and (5) monitoring and further training of the panel. Following these steps, all panelists learned how to perform GC–O analysis. Some variances among subjects were observed; however, the background of the trainees was found to be insignificant. Assessors for the “professional” GC–O panel were chosen for further training and included people with a sensory and food science background, but also ordinary consumers. The PI method, where subjects rate odor intensity after a peak eluted, was found to provide a sufficient amount of data for key compound analysis. The method enabled easy data handling, provided valuable feedback for panel monitoring, and aided in the selection process to decide which assessors would be suitable for further training and placement on a professional panel.

Aims Tree roots in forest soils can be detected using nondestructive ground-penetrating radar (GPR). However, few studies have investigated root detection frequency; i.e., how many and which roots are identified in a radar profile out of the total quantity of roots present in a forest stand. The objective of this study was to quantify root detection frequency and uncertainty, including relationships between root detection and radar parameters using 1.5 GHz GPR in a Pinus thunbergii forest on sandy soils.

Concentrations of butyltin (BT) and phenyltin (PT) compounds were measured in organs and tissues of dugongs (Dugong dugon) from the coastal waters of Thailand. Concentrations of BTs and PTs were in the range of 14-14,468 and

The coherent diffusion of the resonance radiation was studied in the case of the excitation by amplitude-modulated light in weak magnetic fields of about 2 and 4 G. The width of the observed resonance curves decreased with the increase of the Hg atomic density in the case when the detection frequency was equal to the frequencyf of the modulation of the exciting light as well as in the case of detection frequency two times greater (2f).

Uncertain frequency detection of brief sinusoids in noise was studied in a special Yes-No paradigm that included single-frequency trials randomly interleaved with trials on which either of two frequencies could be presented. Contrary to implications from previous studies, and to sensory filter models of attention, the Os’ deliberate attempts to impose narrow- or wide-band listening had only a small effect on the relative detectability of signals at 500 Hz and at 1100 Hz. If frequency selectivity is to be understood as sensitivity adjustment (rather than as a recognition process), the relevant parameters may be entirely stimulus determined.

It has been shown by Wetsel, Jr. and Spicer that, in the special case of nonlinear boundary conditions, the resolution of a thermal wave microscope increases with the square root of the detection frequency. Such a case offers no gain above the linear detection technique. In this paper we treat the more general situation in which bulk parameters are also nonlinear. It is shown that under these circumstances the nonlinear resolution is proportional to the detection frequency. Direct proportionality involves superior resolution in nonlinear imaging.

I HAVE earlier postulated1,2 a completely new concept of the insect environment based on infra-red frequency transmission through infra-red atmospheric windows. This concept involves the utilization of such transmitted frequencies in the life cycle and behaviour of night-flying moths. I postulated that moths may locate their mates, chemical releasers (scents), and host plants by means of infra-red frequency detection and that the night-adapted eye of nocturnal moths shifts slowly from the short-wave visible spectrum of daylight to the longer and longer infra-red frequencies as it becomes night-adapted. When totally dark-adapted, it attains the configuration of a mosaic optic-electromagnetic thermal radiometer for night-time detection of infra-red frequencies. I further postulated that the antennal spines may be resonant cavities for infra-red detection. Laithwaite3 has postulated a similar theory for the assembling of moths. In testing the validity that a moth might locate its mate by thermal far infra-red, the following experiments were performed