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Computer vision techniques are widely applied to the object detection, license plate recognition, remote sensing, and outdoor monitoring system. The performance of these applications mainly relies on the high quality of outdoor image. However, an outdoor image can be led to contrast decrease, color distortion, and unclear structure by poor weather conditions and human factors such as haze, fog, and air pollution. These issues may lower down the sharpness of a photo. Despite of the single-image dehazing is used to solve these issues, it cannot achieve a satisfactory result when the method deals with the bright scene and sky area. In this article, we aim to design an adaptive dehazing technique based on fusion transmission and sky weight detection. The sky weight detection is employed to distinguish the foreground and background, while detected results are applied to the fusion strategy to calculate deep and shallow transmissions. Thus, this can get rids of the subject of over-adjustment. Experimental results have demonstrated that the new method can outperform the latest state-of-the-art methods in terms of subjective and the objective assessments. &nbsp

Earthquake swarms have provided useful insights into driving mechanisms for triggered earthquakes. However, a majority of earthquake swarms consist of microseismicity in which observations sometimes are limited because of detection ability. Here, we apply a multi-station template matching technique to two temporary seismic networks and investigate microseismicity in southern Hispaniola. We detect a total of 6065 and 1366 new events for the 2010 and 2013–2014 datasets, respectively, using templates from pre-existing catalogs. The magnitude of completeness (Mc) of our updated catalogs drops from 1.7 to 1.2 and from 2.2 to 1.4 for the 2010 and 2013–2014, respectively, after combining new detections with the templates. With the improvement of seismic detections, the spatiotemporal distribution of the seismicity showcases three instances of earthquake swarms. The first one is located offshore on the Trois Baies fault, with over one thousand events triggered during mid-February to early March 2010, whereas the other one is distributed along the western Léogâne fault, which occurs within a day and shows many earthquakes with similar waveforms. The third one is found in the north of Lake Enriquillo in the Dominican Republic, which outlines a nearly vertical fault plane. Our updated earthquake catalogs and observations of these swarms provide necessary information for seismic hazard assessment in southern Hispaniola and will facilitate continued investigations of seismology in the area.

Given the inadequacy of assessed outcomes (e.g., final exam) and the importance of evaluating the learning process in STEM education, we use deep learning to develop the STEM learning behavior analysis system (SLBAS) to assess the behavior of learners in STEM education. We map learner behavior to the ICAP (interactive, constructive, active, passive) framework, helping instructors to better understand the learning process of learners. The results show that SLBAS exhibits high accuracy. Moreover, Cohen’s kappa coefficient between expert coding and SLBAS is high enough to support replacing expert coding in the observation method with SLBAS to recognize the learning process of learners during STEM activities. Finally, statistical analysis establishes a correlation between the learning process and learning effectiveness. The results of this study are in line with most previous studies, demonstrating that STEM education differs from traditional teacher-centered courses in that it helps learners to improve the process of knowledge construction with practice and hands-on opportunities rather than simply receiving knowledge passively.

This paper presents a node-reliability based cyclic redundancy check (CRC)-aided successive cancellation list (NRB CA-SCL) polar decoder architecture, where node reliability is used to determine the number of expanding paths, and a priority-based sorter is devised so as to reduce the number of sorting cycles. In order to reduce the effort required for sorting by the node processor, the expanding segments are generated using off-line flipping patterns. We also propose a post-processing scheme that improves the error-rate performance for the NRB CA-SCL decoders. The proposed techniques are demonstrated by implementing (1024, 512) polar decoders. Compared to other state-of-the-art CA-SCL decoders, the proposed decoder, when the post-processing technique is not included, achieves a better area efficiency. When the post-processing technique is included, the proposed list-16 decoder achieves an area efficiency that is almost 2.5 times greater compared to the latest list-32 CA-SCL decoder, as well as a similar error-rate performance.

Coronavirus disease 2019 (COVID-19) has caused a global pandemic and exerted a profound physiological and mental impact on the public. Due to anxiety from being bombarded by information from the news and social media, people may constantly read and repost, with a fear of missing out (FOMO), information about COVID-19 on social media. So far, there has been little research on COVID-19 FOMO. We therefore compiled the COVID-19 information fear of missing out scale (CIFS) and administered it to 1178 adults in Taiwan to identify the possible factors influencing CIFS scores. We demonstrated that the CIFS had good reliability, factor validity, and criterion validity. With regard to demographic variables, we found that gender, marital status, travel time to the nearest hospital, and educational background influenced CIFS scores. In contrast, the participant age and whether he or she lived in an urban area did not affect the CIFS scores. With regard to social media usage, social media usage time (r = 0.025) and the numbers of COVID-19-related posts read on social media (r = 0.117) or instant messaging (r = 0.169) were not highly correlated with CIFS scores. Rather, CIFS scores were found to be significantly correlated to the frequency of reposting COVID-19-related information on social media (r = 0.497) and on instant messaging (r = 0.447). These results indicate that CIFS scores are closely associated not with passive browsing on social media but with the frequency at which an individual actively reposts information. In other words, what creates CIF is not an overabundance of information (i.e., an infodemic) but the active reposting and interpretation of information. Individual autonomy for interpretation of the received information and self-determination about reposting are key factors for COVID-19 information FOMO. When facing the COVID-19-related news on social media, it is the active information-related FOMO, not the passive infodemic, that influences our social media usage.

In order to minimize the decoding period and the response time for Polar Codes, an early termination (ET) scheme based on additional check points (ACPs) is proposed in this work. For conventional ET schemes based on distributed parity-check (PC) bits, ET can only be triggered when the decoding process reaches the PC bits. The ACPs are selected from the information bits, and extend the feature of the PC bits, where ET can also be triggered at the ACPs, meaning that a more rapid ET is available that does not impact the error-rate performance. With sophisticated method of selecting ACPs based on the channel-independent polarization weight (PW), the proposed ET scheme is able to reduce the response time by about 5

In this study, a coupled ocean–atmosphere model was used to simulate the evolution of Typhoon Nanmadol (2011), an intense typhoon that drifted over the Kuroshio Current over a 2-day period, encountering land twice, once in the Philippines and once in Taiwan. Sensitivity experiments were performed to elucidate the influence of the three-dimensional ocean structure on predictions of typhoon intensity, with a focus on the interaction between the typhoon and the Kuroshio Current in the Luzon Strait (LS) and the unique path of Nanmadol. The cooling of the sea surface, which was associated with frontal movement in the LS, significantly reduced the intensity of the typhoon. The improved predictions of Nanmodal's intensity resulting from this complex interaction between the ocean and atmosphere occur only in model runs which include full two-way coupling between oceanic and atmospheric processes.

The air pollution and foggy weather often result in serious distortion while taking photos or recognizing patterns. He et al. have introduced the dark channel prior to solve this dehazing problem. Unfortunately, it cannot function well once the color difference of target image is large. More precisely, the dehazed result looks unnatural. Thus, we aim to develop a brand-new visibility dehazing technique based on the channel-weighted analysis and illumination tuning. The channel-weighted analysis is adopted to eliminate the unnatural effect, while the illumination tuning is applied to refine the details. Simulation results have demonstrated that the new method can guarantee the readability of a hazed image after removing noise, including the foggy photo and sandstorm one.

Introduction Although infection was the most common symptom in patients returning to the ED, whether intravenous antibiotic administration at the index visit could serve as an indicator of patients with infectious diseases at high risk for hospital admission after returning to the ED within a short period of time remains unclear. The study aimed to investigate the potential risk factors for hospital admission in patients returning to the ED within 72 hours with a final diagnosis of infectious diseases. Material and methods This retrospective cohort study analyzed return visits to the ED from January to December 2019. Adult patients aged >20 years who had a return visit to the ED within 72 hours with an infectious disease were included herein. In total, 715 eligible patients were classified into the intravenous antibiotics and non-intravenous antibiotics group (reference group). The outcome studied was hospital admission to general ward and intensive care unit (ICU) at the return visits. Results Patients receiving intravenous antibiotics at index visits had significantly higher risk—approximately two times—for hospital admission at the return visits than those did not (adjusted odds ratio = 2.47, 95% CI = 1.34–4.57, p = 0.004). For every 10 years increase in age, the likelihood for hospital admission increased by 38%. Other factors included abnormal respiratory rate and high C-reactive protein levels. Conclusions Intravenous antibiotic administration at the index visit was an independent risk factor for hospital admission at return visits in patients with an infection disease. Physicians should consider carefully before discharging patients receiving intravenous antibiotics.

Compositional abruptness of the interfaces is one of the important factors to determine the performance of Group IV semiconductor heterojunction (Si/Ge or Si/SiGe) nanowire devices. However, forming abrupt interfaces in the nanowires using the common vapor-liquid-solid (VLS) method is restricted because large solubility of Si and Ge in the Au eutectic liquid catalyst makes gradual composition change at the heterojunction after switching the gas phase components. According to the VLS growth mechanism, another possible approach to form an abrupt interface is making a change of the semiconductor concentration in the eutectic liquid before precipitation of the second phase. Here we show that the composition in AuSiGe eutectic liquid on SiGe nanowires of low Ge concentration (≤6%) can be altered by thermal oxidation at 700 °C. During the oxidation process, only Si is oxidized on the surface of the eutectic liquid, and the Ge/Si ratio in the eutectic liquid is increased. The subsequently precipitated SiGe step at the liquid/solid interface has a higher Ge concentration (∼20%), and a compositionally abrupt interface is produced in the nanowires. The growth mechanism of the heterojunction includes diffusion of Si and Ge atoms on nanowire surface into the AuSiGe eutectic liquid and step nucleation at the liquid/nanowire interface.

We report the temporal change of the near-surface(

The Science, Technology, Engineering, Arts, and Math (STEAM) has become the buzzword in the field of education. Many studies have revealed the importance of STEAM education and proposed different strategies to enhance it, nevertheless, these strategies are not in perfect alignment with five disciplines of STEAM. Therefore, this study proposed an assessment model which can match each discipline of STEAM activities respectively, including Learning, Using, Practicing, Designing, and Applying (LUPDA). We piloted and reviewed this model through the STEAM learning activities of the Micro:bit-Obstacle Avoidance Car. Finally, the LUPDA model provides effective measurement thorough STEAM hands-on activity.

Achieving a high decoding throughput using a successive cancellation list (SCL) decoder for polar codes is difficult due to its sequential decoding architecture. In this work, combining the local sorter from a single parity check (SPC) node with a shift-based path memory, a modified fast simplified successive cancellation list (Fast-SSCL) decoder is proposed, in order to provide a high-throughput using a low-complexity implementation. The proposed modified Fast-SSCL decoder can be operated at 470 MHz and was synthesized with an area of 5.26 mm2 using a TSMC 90 nm CMOS process. The decoder presented in this work is able to improve the throughput to area ratio (TAR) by more than 30% compared with the previous designs.

This paper presents hardware-friendly LDPC decoding schedules for 5G hybrid automatic repeat request (HARQ) applications. Since there are built-in punctured blocks in the parity check matrix (PCM), a scheduling technique is proposed that allows the punctured nodes to be efficiently recovered. For HARQ using the Chase combining (CC), the previous decoding results corresponding to the punctured part are retained, and the proposed layered decoding is arranged according to the row weight. For HARQ using the incremental redundancy (IR) approach, the parity bits corresponding to the pure-row-orthogonal part of the PCM are transmitted first. The hardware implementation shows that the throughput can be increased by 21.37% for the first decoding attempt, 56.9% for CC-HARQ and 14.51% for IR-HARQ when the code rate reaches 0.303.

A fundamental challenge in chemical biology and medicine is to understand and expand the fraction of the human proteome that can be targeted by small molecules. We recently described a strategy that integrates fragment-based ligand discovery with chemical proteomics to furnish global portraits of reversible small molecule-protein interactions in human cells.Excavating clear structure-activity relationships from these “ligandability” maps, however, was confounded by the distinct physicochemical properties and corresponding overall protein-binding potential of individual fragments. Here, we describe a compelling solution to this problem by introducing a next-generation set of fully functionalized fragments (FFFs) differing only in absolute stereochemistry. Using these enantiomeric probe pairs, or “enantioprobes”, we identify numerous stereoselective protein-fragment interactions in cells and show that these interactions occur at functional sites on proteins from diverse classes. Our findings thus indicate that incorporating chirality into FFF libraries provides a robust and streamlined method to discover ligandable proteins in cells.

Understanding the growth mechanism of heterojunctions in silicon-germanium alloy (Si-Ge) nanowires is helpful for designing adequate physical properties in the material for device applications. We examine the formation of the heterojunction in low Ge-content Si-Ge nanowires by an approach of thermal oxidation, which produces an atomically abrupt interface with an obvious concentration change. Forming heterojunctions in Si-Ge nanowires by this approach involves more complicated reaction routes than direct growth of heterojunction nanowires using the vapor-liquid-solid method. At the beginning of the oxidation process, the AuGeSi eutectic liquid at the nanowire tip significantly etches the Si-Ge alloy nanowires. Selective oxidation of Si results in a change of the relative amount of Ge to Si in the eutectic liquid, which further modulates the solubility of Ge and Si atoms. The compositional variation in the Au-Ge-Si ternary alloy system during the oxidation process accounts for the observed concentration profile in the heterojunction nanowire. The thermal oxidation approach is applied on a low Ge-content Si-Ge thin film that is coated with Au nanoparticles. Si-Ge nanodots, which exhibit a higher Ge concentration, are precipitated epitaxially in the film, as a result of compositional modulation in the AuGeSi eutectic liquid.

In this study, an integrated concept mapping and gaming-based learning approach was proposed to support mobile learning activities. To investigate the effects of the interaction between concept mapping and gaming on the participants' mobile learning outcomes, a quasi-experimental design was adopted and conducted for a learning activity of the elementary school course unit 'knowing the representative rocks in different geographical locations in Taiwan'. The participants were divided into three experimental groups and one control group. The experimental groups used the integrated concept mapping and gaming-based mobile learning approach, the gaming-based mobile learning approach and the integrated concept mapping and guidance-based mobile learning approach, respectively. On the other hand, the control group used the conventional guidance-based mobile learning approach. The experimental results showed that no interaction was observed between the gaming approach and the concept mapping approach. Furthermore, it was found that the concept mapping approach was not beneficial for students' learning achievement, while the gaming approach significantly improved their learning motivation, learning satisfaction and flow experience. Finally, discussion is provided to explain the findings, in particular, to infer why concept mapping did not achieve the expected positive impacts, as a reference for future studies.

Background and Purpose Diabetic ketoacidosis (DKA) and hyperglycemic hyperosmolar state (HHS) are usually life threatening, but the recent trend of 28-day case-fatality and associated risk factors including Charlson index have not been known. Our aim was to evaluate the 28-day case-fatality rate among hospitalized DKA and HHS patients in a teaching hospital in Taiwan from 1991 to 2005. Methods DKA and HHS admissions, identified from in-patient electronic database, were linked to Taiwan's national death registry. Kaplan-Meier analysis was used to determine the 28-day case-fatality rates of DKA and HHS, and to compare the trend of case-fatality over three consecutive 5-year periods (i.e, 1991-1995, 1996-2000, 2001-2005). We also used the Cox proportional hazard regression model to explore the determinants of 28-day case-fatality of the study patients. Results The 28-day case-fatality rates for DKA and HHS were 6.10% and 18.83%, and the lowest ones were observed in 2001-2005 (2.65% and 11.63% in DKA and HHS, respectively). Pneumonia was a significant predictor for increased 28-day case-fatality in both illnesses. Additionally, older age and stroke were significantly associated with increased case-fatality in DKA patients while myocardial infarction and higher Charlson index were significant predictors for higher case-fatality in HHS patients. Conclusion Improvements in case-fatality in recent years for both DKA and HHS were found in the study hospital. Further reduction of the case-fatality rate among DKA and HHS patients can be achieved by optimal management of certain co-morbidities.

Certain factors originating from the perinatal and childhood periods are suspected of contributing to the recent increasing trend of childhood type 1 diabetes (T1D) incidence. This study sought to investigate the relationships between various perinatal and childhood risk factors and T1D incidence in young children (10 years).We used a nested case-control design based on 1,478,573 live births born in 2000-05 in Taiwan. Cases were 632 incident cases of T1D between 2000 and 2008. Ten matched controls for each case were randomly selected. Information on various perinatal risk factors was also identified from claim data. Multiple conditional logistic regression was employed to estimate odds ratio (OR) and 95 confidence interval (CI) of T1D.Childhood infection was significantly associated with an increased risk of T1D (OR = 1.46, 95% CI = 1.23-1.73). Increased risk of T1D was also noted in children born to younger mothers (25 years) (OR = 1.94, 95% CI = 1.34-2.81), older fathers (30 years) (OR = 1.56 (95% CI = 1.16-2.10) to 1.57 (95% CI = 1.19-2.05), mothers with Caesarean section (CS) (OR = 2.35, 95% CI = 1.52-3.64), and mothers with gestational diabetes mellitus (OR = 4.36, 95% CI = 2.76-7.77). Fathers with T1D (OR = 7.36, 95% CI = 1.02-57.21) or type 2 diabetes (OR = 1.54, 95% CI = 1.04-2.26) were observed to substantially increase the risk of offspring T1D.Certain modifiable perinatal factors such as infection and CS may predispose incidence of T1D in young children.

Background: Many reports in the literature suggest that chronic hepatitis C virus (HCV) infection is associated with diabetes, but the results are conflicting. The aim of our study was to investigate the seroprevalence of hepatitis B virus (HBV) and HCV infections in type 2 diabetes mellitus (DM) patients. Methods: We collected 820 consecutive type 2 diabetic patients attending 2 of 5 outpatient endocrinology clinics in Far Eastern Memorial Hospital from March to July 2003. The control group consisted of 905 subjects who came for medical check-ups at the Family Medicine Department. We determined hepatitis B surface antigen (HBsAg) and anti-HCV in both groups, using third-generation microparticle enzyme immunoassay. Results: No significant difference was found between type 2 DM patients and the control group for seropositivity of HBsAg (13.5% versus 12.4%; odds ratio (OR) = 1.09; 95% confidence interval (CI): 0.77-1.55; p = 0.441), but anti-HCV seropositivity was detected in 6.8% of patients and 2.6% of the control subjects (OR = 2.87; 95% CI: 1.51-5.46; p < 0.001). In anti-HCV-positive DM patients, abnormal alanine aminotransferase was observed in 61.8%, compared with only 34.2% of anti-HCV-negative DM patients (p < 0.001). We did not observe any difference in risk factors for HCV infection between anti-HCV-positive and -negative DM patients. Conclusion: The rate of seropositive anti-HCV is 2.8 times higher in type 2 DM patients than non-diabetic control subjects. (J Chin Med Assoc 2006;69(4):146-152)

A stacking metal-insulator-semiconductor (MIS) solar cell structure, which integrates an n-type MIS solar cell with a p-type MIS solar cell, is proposed to effectively enlarge the open-circuit voltage (Voc). The measured Voc is up to 0.71 V under simulated air mass 1.5 illumination (100 mW/cm2). This Voc is larger than those of the n-type or p-type MIS solar cells with or without surface passivation. In this letter, we successfully demonstrate the feasibility of the Voc enhancement of MIS solar cells by using a stacking structure.

The hard clams (Meretrix lusoria) that are cultured in Taiwan have suffered high mortalities each spring and/or summer since 1969. Environmental factors, pollution and infectious diseases have been implicated, but no single factor has been shown to lead directly to large-scale death of the cultured hard clam. In the present study, attempts were made to examine the effects of heavy metals on the susceptibility of the hard clam to birnavirus infection. First we determined the stability of the clam birnavirus in sea, brackish, fresh waters at 4, 15 and 26°C and in solutions containing different concentrations of Zn2+, Cd2+, Cu2+, and Hg2+. For each heavy metal cation, two concentrations which had no influence on clam birnavirus infectivity were selected and used to treat the hard clams before and after virus infection. In experiment I, clams were immersed in 105.0 TCID50 /ml virus solution for 24 h and subsequently exposed to one of the heavy metals. Cumulative mortalities of clams were 20∼52% in most experimental groups although mortalities reached 91% in infected clams exposed to high concentrations of copper. In experiment II, groups of 60 clams were exposed to one of the heavy metals for 7 days and then infected with the virus, while controls were only expose to heavy metals. Mortalities of clams in the experimental groups reached 65∼90% within 28 days, while only 10% mortalities were observed in the groups that were exposed to either heavy metals or virus infection alone.

Silver nanowire (Ag NWs) have been successfully synthesized by thermally assisted photoreduction (TAP) of aqueous silver nitrate (AgNO 3 ) solution on titanium dioxide (TiO 2 ) films [1]. Nevertheless, the nucleation and nucleation and growth of the Ag NWs on TiO 2 substrate were monitored in detail by in-situ synchrotron radiation x-ray diffraction (SR-XRD). As-annealed TiO 2 film, followed by heating from 60 to 300°C, shows strong in-situ SR-XRD ratios of Ag(220)/Ag(200) spectra, indicating the preferred growth direction of NWs toward . The nano-Auger electron spectrum (AES) demonstrates that silver nano-particles could was locally at room temperature on as-annealed TiO 2 , which was partially excited by blackbody radiation. These Ag clusters will act as nucleation site for Ag NWs. It implies that the homogeneity and amount of electrons on the TiO 2 surface and the accumulative direction of Ag atoms are the key points for Ag Nws synthesis.

Session initial protocol (SIP) is a signaling control protocol for creating, modifying, and terminating the multimedia sessions. SIP can provide personal mobility by addressing a single user located at different terminals according to a unique logical address. Moreover, user may register multiple contact addresses to VoIP servers and the server will fork the incoming request to these contact addresses. In this paper, we propose an improvement to reduce the traffic cost for sending INVITE requests by dividing the destination addresses into active and standby groups and phasing the forking processes. Furthermore, the numbers of miss calls and the repeated registrations will be bounded to balance performance and the accuracy of active group.

Ectopic thyroid tissue is a rare entity in thyroidology; however, the occurrence of thyroid carcinoma in such aberrant thyroid tissue has been reported. Carcinoma arising in subhyoid thyroid is especially unusual, with even fewer reports published. Usually, surgical excision is considered to be therapeutic strategy for managing possible malignancy in ectopic thyroid. Thyroid ultrasonography, radioactive iodine scanning, and fine-needle aspiration cytology are rapid, safe, and minimally invasive diagnostic procedures. We report one case of papillary carcinoma in subhyoid ectopic thyroid to emphasise the importance to evaluate all ectopic thyroid tissues.

A series of anatase phase Fe-doped TiO2 nanoparticles are prepared by a modified sol-gel method. Spontaneous Raman spectroscopy is utilized to characterize the crystal structures of these nanoparticles and investigate their structural transformation under the exposure of a 532 nm green laser. The anatase phase of TiO2 can be effectively converted into the rutile phase with the assistance of Fe doping. It is found that the critical laser intensity for phase transformation decreases with increasing the Fe content. We ascribe this tendency to the enhanced optical absorption and the photo-induced thermal heating effect, which can be associated with the defect structure within the bandgap of Fe- TiO2 nanoparticles. Our study demonstrates an all-optical approach to pump and probe the phase transformation of metal-doped TiO2 nanoparticles.

Patients with nonthyroid illness (NTI) often have reduced serum T3, free T3, T4, and free T4 concentrations. Paradoxically, serum TSH is usually in the normal range. The data suggest a diagnosis of hypothalamic hypothyroidism, in which TSH may have reduced biological activity because TRH, which is necessary for key steps in the glycosylation of TSH, is deficient. To study the glycosylation of TSH in patients with NTI, we measured the serum TSH concentration in 36 such patients hospitalized on our intensive care units and compared the results with those from a group of 18 normal subjects. Serum TSH was measured in 2 assays: 1) a sensitive TSH RIA of unextracted serum (TSH-RIA) and 2) a RIA of serum TSH after its extraction with Concanavalin-A (Con-A), a lectin which binds glycoproteins containing mannose residues in their oligosaccharide side-chains (TSH-Con-A). The ratio of TSH-Con-A to TSH-RIA was significantly reduced in the NTI patients [0.61 +/- 0.03 (+/- SE) vs. 0.89 +/- 0.05 in the normal subjects] due to reduced binding of the TSH to the Con-A. This change was not dependent on the extent of the abnormalities of thyroid hormone levels. The data suggest that the TSH secreted in NTI has altered glycosylation which is associated with reduced biological activity. This finding may explain in part the low serum T4 level in NTI patients in the face of an apparently normal immunoreactive TSH level.

We evaluated an immunoenzymatic assay (Abbott HTSH EIA) for thyrotropin (TSH) as a tool for detecting hyperthyroidism and for monitoring thyroid hormone suppressive therapy in patients with nodular goiter, thyroid carcinoma, and hypopituitarism. We also tested with thyroliberin (TRH), to determine the correlation between peak and basal TSH in suppressed patients. For comparison, we used a nonequilibrium radioimmunoassay optimized for maximum sensitivity (J Clin Endocrinol Metab 1975;41:676). Hyperthyroid patients with values for either or both triiodothyronine and thyroxin above the normal reference interval had Abbott assay values less than or equal to 0.2 milli-int. unit/L, clearly below the Abbott assay normal range, as determined in 116 euthyroid subjects. We detected one-third of the suppressed patients (greater than or equal to 0.3 milli-int. unit/L) with RIA, 69% with the Abbott assay (TSH greater than or equal to 0.04 milli-int. unit/L). Only 20% of patients with undetectable basal TSH values in the Abbott assay responded to TRH with a detectable peak TSH value; the peak TSH value after TRH was proportional to the basal TSH value. A single basal TSH measurement by the Abbott HTSH EIA should be adequate for monitoring the degree of thyroidal suppression in thyroid-hormone-treated patients.

hCG stimulates thyroid function, but it has been suggested that it is impurities in commercial hCG preparations or a variant of hCG that are responsible for the thyrotropic activity. In this study, we tested the thyrotropic activity of purified and commercial hCG and compared its action with that of bovine TSH (bTSH) in cultured rat FRTL-5 cells in regard to stimulation of iodide uptake, activation of adenylate cyclase, and synthesis of DNA. Iodide uptake was measured after incubation of the cells for 48-72 h with the test hormones, followed by a 40-min incubation with 0.1 microCi Na125I and 10 mumol/L carrier NaI; the 125I in the washed cells was counted. Adenylate cyclase was measured after incubation of the cells with the test stimulators for 3 h in hypotonic medium by RIA of cAMP in the medium. DNA synthesis was measured after incubation of the cells with the test substances for 24 h, followed by addition of [3H]thymidine for 3 h and then measuring the incorporation of [3H]thymidine into the cells. Both purified and commercial hCG produced a dose-related increase in iodide uptake. The relative potency of commercial hCG was 0.024 microU bTSH/U hCG and that of purified hCG was 0.042 microU bTSH/U hCG; compared with human TSH, the potency of purified hCG was 0.72 microU/U hCG. hCG caused a dose-related increment of adenylate cyclase and [3H]thymidine incorporation. The effect of hCG on iodide uptake and [3H]thymidine incorporation was additive with that of bTSH; hCG was not an antagonist of TSH in these cultured rat thyroid cells. We conclude that hCG has intrinsic thyrotropic activity in FRTL-5 cells in regard to stimulation of iodide uptake, activation of adenylate cyclase, and stimulation of DNA synthesis.