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PURPOSE In the case of a nuclear incident, the release of radioiodine must be expected. Radioiodine accumulates in the thyroid and by irradiation enhances the risk of cancer. Large doses of stable (non-radioactive) iodine may inhibit radioiodine accumulation and protect the thyroid ('thyroid blocking'). Protection is based on a competition at the active carrier site in the cellular membrane and an additional temporary inhibition of the organification of iodide (Wolff-Chaikoff effect). Alternatively, other agents like e.g. perchlorate that compete with iodide for the uptake into the thyrocytes may also confer thyroidal protection against radioiodine exposure.Biokinetic models for radioiodine mostly describe exchanges between compartments by first order kinetics. This leads to correct predictions only for low (radio)iodide concentrations. These models are not suited to describe the kinetics of iodine if administered at the dosages recommended for thyroid blocking and moreover does not permit to simulate either the protective competition mechanism at the membrane or the Wolff-Chaikoff effect. Models adapted for this purpose must be used. Such models may use a mathematical relation between the serum iodide concentration and a relative uptake suppression or a dependent rate constant determining total thyroidal radioiodine accumulation. Alternatively, the thyroidal uptake rate constant may be modeled as a function of the total iodine content of the gland relative to a saturation amount. Newer models integrate a carrier-mechanism described by Michalis-Menten kinetics in the membrane and in analogy to enzyme kinetics apply the rate law for monomolecular irreversible enzyme reactions with competing substrates to model the competition mechanism. An additional total iodide uptake block, independent on competition but limited in time, is used to simulate the Wolff-Chaikoff effect. CONCLUSION The selection of the best model depends on the issue to be studied. Most models cannot quantify the relative contributions of the competition mechanism at the membrane and the Wolff-Chaikoff effect. This makes it impossible or exceedingly difficult to simulate prolonged radioiodine exposure and the effect of repetitive administrations of stable iodine. The newer thyroid blocking models with a separate modeling of competition and Wolff-Chaikoff effect allow better quantitative mechanistic insights and offer the possibility to simulate complex radioiodine exposure scenarios and various protective dosage schemes of stable iodine relatively easily. Moreover, they permit to study the protective effects of other competitors at the membrane carrier site, like e.g. perchlorate, and to draw conclusions on their protective efficacy in comparison to stable iodine.

We consider a situation, when braking is the only way to avoid obstruction of an automotive vehicle or a railroad train with a suddenly detected steadfast obstacle blocking the path. The velocity a...

In indirect-drive inertial confinement fusion, thin films on laser entrance hole (LEH) windows are needed to reflect thermal infrared radiation (IR) and to protect the deuterium-tritium (D-T) cryog...

Power swing due to the disturbance in the power system is a cause of the untrue operation of protective elements. Previously, many blackouts have been perceived and recorded due to reactive power m...

Wearing blue-blocking lenses (BBLs) in the evening hours may not be effective in improving sleep quality. Optometrists need to be informed in prescribing BBLs by highlighting the consequences of their wear to the circadian system.Excessive exposure to artificial light, particularly at short wavelengths, during the evening, may disrupt normal nocturnal melatonin production, which is a natural process of the circadian rhythm and affect sleep quality. Current BBLs have been designed to limit blue-light exposure and may offer a means to minimise disruption to the circadian system. The purpose of this study was to evaluate the impact of BBLs on a normal sleep-wake circadian rhythm.Seven different commercial brands of BBLs (Crizal Prevencia, Smart Blue Filter, Blu-OLP, Blue Control, UV++Blue Control, SeeCoat Blue UV and Blue Guardian) and powers (+2.00 D, -2.00 D and Plano) were evaluated by quantifying the degree to which they reduce light radiation from lamps and electronic devices. In particular, the non-linear circadian index and the circadian stimulus was determined for various light sources to establish changes in melatonin production that occur while viewing through different BBLs.A large difference was shown in the effectiveness of different BBL brands in reducing the spectral sensitivity of the circadian system. The BBL brand was shown to selectively affect the non-linear circadian index and circadian stimulus, particularly with those with transmittance profiles that block the most blue light having the lowest effect on the suppression of nocturnal melatonin secretion.BBLs may not improve sleep quality, because they continue to allow the transmittance of blue light that may suppress nocturnal melatonin secretion and hence disrupt the normal sleep-wake circadian rhythm.

We evaluated the effect of interfering with echoic responses during stimulus pairing on preschool-age children’s responses in tact probes. During stimulus pairing, children viewed presentations of ...

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. TKP is a serine protease extracted from the fruit of Trichosanthes kirilowii. We investigated the impact of TKP on the pro...

Background: N-methyl-D-aspartate (NMDA) receptors are thought to be for pain memory, and blocking them can help to reduce pain. We aimed to assess the preventive effects of small doses of ketamine ...

Being the most abundant renewable source of energy, photovoltaic arrays (PVA) are extensively used for power generation. A number of factors influence performance of the PVAs, among which complete ...

Navigation in harsh environments mostly encounters many problems such as signal blocking due to a variety of obstacles around the receiver. Vectorised receiver has an architecture in which the chan...

The efficiency loss process of hyper-fluorescent organic light-emitting diodes (OLEDs) was analyzed with different fluorescent emitters. Two blocking units of tert-butyl and 2-phenylpropan-2-yl in fluorescent emitters suppressed the Dexter energy transfer from the host and thermally activated delayed fluorescent (TADF) sensitizer to the fluorescent emitter and concentration quenching caused by intermolecular interaction. The performance of the green hyper-fluorescent OLEDs showed that the device of the fluorescent emitter with the 2-phenylpropan-2-yl unit achieved a high external quantum efficiency of 18.1% with a low efficiency roll-off, compared to the device of the fluorescent emitter with the tert-butyl unit. This study demonstrated the usefulness of the 2-phenylpropan-2-yl blocking unit of the fluorescent emitter for hyper-fluorescent OLEDs, and exhibited the directionality of the development of hyper-fluorescent OLEDs.

The lateral tilt of the arms accompanied by trunk lateral tilt is a typical blocking manoeuvre in volleyball. However, during this unanticipated blocking movement, an associated risk of ACL injury may result. The aim of the present study was to compare associative ACL risk factors at the initial contact and the first and second peak of VGRF during an unanticipated blocking movement with different arm positions. Synchronized kinematic and kinetic data were collected for each trial of each condition. Student paired t-tests and effect size were used to determine differences between two conditions (S - with arms straight up from the body) and (T - with the arms and trunk laterally tilted). The results showed that the T condition significantly decreases knee flexion, increases VGRF at the foot contact, first peak force and increases the valgus moment at the first peak force. The values of the associated risk factors for a non-contact ACL injury appear to be related to the tilted arm position accompanied by trunk tilt towards to right lower limb during landing. The players should be taught to land with greater knee flexion and, if possible, a double-leg landing to decrease right lower limb loading during the blocking manoeuvre.

Emerging data indicate that endothelial-mesenchymal transition (EndMT) is involved in the pathogenesis of idiopathic pulmonary fibrosis (IPF). A previous study noted that blocking the activity of protein phosphatase 2 A (PP2A) could attenuate EndMT. However, the treatment effects of PP2A inhibitors in pulmonary fibrosis remain not investigated. In the present study, we used a PP2A inhibitor, a newly designed peptide named TAT-Y127WT, to determine the role of PP2A in pulmonary fibrosis. Herein, we showed that TAT-Y127WT protected mice against BLM-induced pulmonary fibrosis by attenuating lung injury and fibrosis. Furthermore, a mechanistic study indicated that TAT-Y127WT could alleviate EndMT in the lungs following BLM induction. Overall, our data showed that PP2A might participate in pulmonary fibrogenesis by promoting EndMT, and TAT-Y127WT could be a potential candidate for new anti-fibrotic therapies for IPF patients.

As a chronic airway disease, asthma has two characteristics, tissue remodeling and airway inflammation. This research focused on miR-92a to explore how it works in asthma. We revealed that the expressions of miR-92a were decreased in both serum and lung tissues from ovalbumin-induced asthma mouse. Bioinformatics analysis, quantitative polymerase chain reaction (qPCR) and dual luciferase assay revealed that miR-92a targets MUC5AC, which was linked to mucus hypersecretion in the pulmonary tracts. By injecting miR-92a-mimics into the trachea, both the airway hyper-reactivity and airway inflammation can be alleviated in an asthma mouse model which is induced by ovalbumin. Moreover, the goblet cell phenotype of asthmatic mice is significantly reduced by the action of miR-92a. Furthermore, miR-92a blocked interleukin (IL)-13-induced MUC5AC luciferase activity in 16HBE. Together, upregulation of miR-92a expression in asthmatic mice plays a role in blocking goblet cell metaplasia by targeting MUC5AC, and thus in the treatment of chronic airway diseases, miR-92a can prevent epithelial remodeling, which is a reasonable method.

Blocking other users is a common act on Twitter but one which is underexplored from a scholarly perspective, particularly the analysis of mass blocklists. Although traditionally associated with harassment, blocklists are increasingly engaged to create individualised environments that align with users’ personal convictions and exclude apparent transgressors. This study uses a pro-choice blocklist (Repeal Shield) created during the 2018 Irish abortion referendum campaign to explore how users interpret these altered boundaries and blocklists’ influence on the Twitter landscape. A metaphor analysis of more than 2,000 tweets discussing the blocklist highlights the dominant concepts in how users visualise Twitter as both a personal space and a battlefield, in which mental health is a key factor. By drawing on discussions of spatiality, agency, gender and online interactions, we can see how these blocking affordances allow users to exist in spaces in which they construct their own parameters to feel safer, raising questions about how harm, health and risk are understood. The article explores how users make sense of conflicting images like ‘safe spaces’ or ‘echo chambers’, highlighting the apparent policing role held by blocklists. Users are negotiating the type of civic space in which they want to exist as norms of engagement versus avoidance collide; although digital spaces have always accommodated fragmented interests, the technological affordances of blocklists provide more rigid boundaries, highlighting how the evolving architecture of social media allows users to redefine the parameters of their own online spaces.

The shading board has a negative influence on window ventilation while it is blocking direct sunlight. Circle vents are designed in the shading board to decrease the negative ventilation effect bec...

Blue-blocking lenses (BBLs) are marketed as providing retinal protection from acute and cumulative exposure to blue light over time. The selective reduction in visible wavelengths transmitted through BBLs is known to influence the photosensitivity of retinal photoreceptors, which affects both visual and non-visual functions. This study measured the spectral transmittance of BBLs and evaluated their effect on blue perception, scotopic vision, circadian rhythm, and protection from photochemical retinal damage.Seven different types of BBLs from six manufacturers and untinted control lenses with three different powers (+2.00 D, -2.00 D and Plano) were evaluated. The whiteness index of BBLs used in this study was calculated using Commission International de l'Eclairage (CIE) Standard Illuminates D65, and CIE 1964 Standard with a 2° Observer. The protective qualities of BBLs and their effect on blue perception, scotopic vision, and circadian rhythm were evaluated based on their spectral transmittance, which was measured with a Cary 5,000 UV-Vis-NIR spectrophotometer.BBLs were found to reduce blue light (400-500 nm) by 6-43 per cent, providing significant protection from photochemical retinal damage compared to control lenses (p ≤ 0.05). All BBLs were capable of reducing the perception of blue colours, scotopic sensitivities and circadian sensitivities by 5-36 per cent, 5-24 per cent, and 4-27 per cent, respectively depending on the brand and power of the lens.BBLs can provide some protection to the human eye from photochemical retinal damage by reducing a portion of blue light that may affect visual and non-visual performances, such as those critical to scotopic vision, blue perception, and circadian rhythm.

We described an ‘expansion’ phenomenon of the Trichoplax sp. H2. The animals were transferred from algal mats to a Petri dish without food with the subsequent passage into the similar Petri dish. T...

Conventional cellulose diacetate filter tips of cigarette (CDFTC) are poor filtration performance of toxic compounds. However, environmentally benign filter tips can be made by replacing cellulose ...

The incidence of skin cancer has raised in the last few years. One of the important growth factors found in the skin layers is insulin-like growth factor (IGF)-1. It is directly linked with many cancers in different organs. Therefore, we aimed to explore the therapeutic effects of blocking IGF-1 receptor (IGF-R1) pathway by PQ401 in skin cancer as well as studying its effect on tumor invasion markers.We experimentally induced skin cancer in mice by the application of 7,12-dimethylbenz (a) anthracene. Skin samples were removed for determination of gen and protein expression of IGF-1, IGF-R1, glypican-3, MMP9, syndecan-1 and fascin-1 by Western blot and PCR. Moreover, skin sections were stained with hematoxylin/eosin and Mallory.Treatment with PQ401 blocked the expression of IGF-R1 in the skin, which is associated with reduction in the skin cancer-induced tumors and scratches. In addition, PQ401 ameliorated skin cancer induced formation of epidermal atypia and hyperplasia. PQ401 reduced both gene and protein expression of the tumor invasion markers, MMP9, syndecan-1 and fascin-1, without affecting gene and protein expression of glypican-3 and IGF-1 in skin cancer group.Blocking IGF-R1 has therapeutic effects against experimental skin cancer induced in mice. In addition, blocking IGF = R1 attenuated skin cancer-induced activation of tumor invasion markers.Key pointsIGF-1/IGF-R1is highly expressed in different cancers as skin cancer.Blocking IGF-R1 production ameliorated skin cancer.Blocking IGF-R1 attenuated skin cancer-induced activation of tumor invasion markers.

The interferon-inducible myxovirus resistance B (MxB) protein has been reported to inhibit HIV-1 and herpesviruses by blocking the nuclear import of viral DNA. Here, we report a new antiviral mechanism in which MxB restricts the nuclear import of HIV-1 regulatory protein Rev, and as a result, diminishes Rev-dependent expression of HIV-1 Gag protein. Specifically, MxB disrupts the interaction of Rev with the nuclear transport receptor, transportin 1 (TNPO1). Supporting this, the TNPO1-independent Rev variants become less restricted by MxB. In addition, HIV-1 can overcome this inhibition by MxB through increasing the expression of multiply spliced viral RNA and hence Rev protein. Therefore, MxB exerts its anti-HIV-1 function through interfering with the nuclear import of both viral DNA and viral Rev protein.

Based on the classical 1-D isentropic theory, the relationship between the critical blocking ratio and the critical incoming flow Mach number in the evacuated tube is deduced in this paper. Next, a...

Due to super elevation and centrifugal force, close attention is needed to lateral stability of cargo when the train negotiates curves. To guarantee the security of cargo on wagons, proper blocking...

The roles of institutions in blocking successful technological changes are the prime concerns of this paper. A mixed framework is developed for this purpose based on concepts from national innovati...

This article presents a versatile model to estimate capacity requirements along a patient pathway with delays to transfer and discharge caused by blocking after service. Blocking after service is a...

At present, the most effective means of releasing the ‘water blocking damage’ in the near-well zone is to change the wettability of the rock surface from liquid wetting to gas wetting. Previous stu...

Fine dust contributes to many physical diseases in coal miners, and it is hard to remove effectively. In this paper, the gas-solid two-phase flow theory and the discrete phase model are use...

Parents’ rights to make medical decisions for their children are not absolute and can be limited where the parents’ decision is likely to cause serious harm to their child. Following this reasoning...

Improving the bed allocation policy can alleviate the blocking, a situation where admitted patients cannot be transferred from the Emergency Departments (the upstream) to inpatient departments (the...

sPLA2 is released under inflammatory conditions from neutrophils, basophils and T-cells. They cleave the cellular phospholipids leading to the release of arachidonic acid and there by provide inter...

This study examines how the delay and blocking of studies on the origin of the virus and, at the same time, the effects they have caused or, as the case may be, reactivated have led several Western...

Introduction: The Hippo pathway represents a new and intriguing opportunity for the treatment of cancer. Activation or overexpression of Yes-associated protein (YAP) or transcriptional coactivator ...

Urban-canyon positioning encounters many problems such as successive attenuation and even blocking of the signals. Vectorised receiver is a solution in which stronger signals aid weak and blocked o...

This study investigated the ameliorative and protective effects of long-term obestatin administration (80 nmol/kg/ intraperitoneal injection (i.p.)) on the pathogenesis of high-fat diet (HFD) induced nonalcoholic fatty liver disease (NAFLD) in rats. Rats (n = 8/group) were divided as control, NAFLD, NAFLD + Simvastatin, NAFLD + obestatin, NAFLD then obestatin, and obestatin then NAFLD. Obestatin co -or post-therapy significantly reduced hepatomegaly and reversed hyperlipidemia, hepatic lipid accumulation, and insulin resistance (IR). Mechanistically obestatin treatments in these rats significantly prevented the increases in final body weights and food intake. Concomitantly, it enhanced circulatory adiponectin levels and hepatic signaling as evident by elevated hepatic protein levels of adiponectin receptors (adipoRII), carnitine palmitoyltransferase-1 (CPT-1), peroxisome proliferator-activated receptor- α (PPAR-α), and phosphor-AMPK (p-AMPK). In addition, obestatin enhanced total circulatory ghrelin levels and significantly increased deacylated ghrelin to acylated ghrelin (DAG/AG) ratio. These data suggest that obestatin reverses and protects against development or progression of NAFLD directly by modulating ghrelin and adiponectin signaling or indirectly by lowering food intake.

This report analyzes how the Russian courts apply the digital anti-piracy law through blocking websites and how this law made a difference in the digital content industry in Russia.

Maura Priest (2019) argues that puberty-blocking treatment (PBT) should be made available to gender-dysphoric adolescents “who (after an evaluation) are deemed good candidates” (XX), even in the fa...

We present a series of experimental investigations in which a differentially-heated annulus was used to investigate the effects of topography on rotating, stratified flows with similarities to the Earth’s atmospheric or oceanic circulation. In particular, we compare and investigate blocking effects via partial mechanical barriers to previous experiments by the authors utilising azimuthally-periodic topography. The mechanical obstacle used was an isolated ridge, forming a partial barrier, employed to study the difference between partially blocked and fully unblocked flow. The topography was found to lead to the formation of bottom-trapped waves, as well as impacting the circulation at a level much higher than the top of the ridge. This produced a unique flow structure when the drifting flow and the topography interacted in the form of an “interference” regime at low Taylor number, but forming an erratic “irregular” regime at higher Taylor number. The results also showed evidence of resonant wave-triads, similar to those noted with periodic wavenumber-3 topography by Marshall and Read (Geophys. Astrophys. Fluid Dyn., 2015, 109), though the component wavenumbers of the wave-triads and their impact on the flow were found to depend on the topography in question. With periodic topography, wave-triads were found to occur between both the baroclinic and barotropic components of the zonal wavenumber-3 mode and the wavenumber-6 baroclinic component, whereas with the partial barrier two nonlinear resonant wave-triads were noted, each sharing a common wavenumber-1 mode.

This article examines the current internet content regulatory regime in Ethiopia from the perspectives of the extensively discussed and broadly accepted regulatory models namely statutory regulatio...

Toxic elements are commonly used in cosmetic products for many reasons like coloring pigments or blocking ultraviolet light; however, the level of some metals exceed specific concentration which ca...

An emerging class of agents blocking IL-17 signaling represents a very promising therapeutic approach. One of these agents, brodalumab, has been associated with an increased risk of suicide behavior. Areas covered: This review sought to provide an overview strictly focused on suicide behavior signals related to the use of IL-17 agents. Data collection regarding this peculiar safety aspect was primarily based on: (i) a revision of safety outcomes belonging to phase II and phase III trials; (ii) a systematic search using the Pubmed Medline database; and (iii) collecting recent data issued as posters or communications in eminent international meetings. Expert opinion: Whilst secukinumab and ixekizumab were not associated with increased signal of suicidal behavior, being recently approved for the treatment of psoriasis by EMA and FDA, brodalumab raised concern because of suicide behavior cases that led to pause momentarily its development program during pre-marketing stage before obtaining the positive recommendation by an FDA advisory panel for its approval. Indeed, a careful re-evaluation of brodalumab safety profile is being performed and no evidence clarified a significant association or a pathogenic mechanism linking brodalumab treatment to the risk of suicidal behavior, suggesting that cases of suicidal behavior accidentally occurred during brodalumab trials.

Iran's nuclear program survived, and the American decision to concentrate on ISIS in both Syria and Iraq has been at the expense of blocking Iran in both those countries. Sunni-led Arab states tole...

The 5-HT4 receptor (5-HT4R) agonists are important in treating gastrointestinal motility disorders. Their role is currently being evaluated for the treatment of cognitive and mood disorders. A selective 5-HT4R antagonist GR 125487 is used in many biological assays to cross confirm the 5-HT4R agonist’s activity. A practical synthesis of GR 125487 is developed so as to have it in desired quantities. The synthesis consists of seven steps starting from commercially available methyl 5-fluoroindole 3-carboxylate. The GR 125487 thus synthesized was used in blocking the activity of 5-HT4R agonist compound in animal models of cognition.

The marine electromagnetic transmitter sends high-power variable-frequency electromagnetic waves to acquire seabed structure and distribution law of mineral resources. The traditional transmitter has some shortcomings, such as small power, low efficiency, and poor load adaptability. In this article, a novel transmitter circuit composed of zero voltage zero current switching (ZVZCS) controlled-source circuit is proposed, which overcomes the limitations of a zero-voltage switching one, such as high freewheeling energy, duty ratio loss, and limited zero-voltage switching load range for the lagging-leg switches. Current in primary winding during the freewheeling period is reduced to zero by using a blocking capacitor and a saturable reactor, realizing zero-current switching turn-on for leading-leg switches, as well as zero-current switching for lagging-leg switches. Finally, the proposed circuit is verified by a 200-A marine transmitter.

To make a copy of her husband's film she pointed a camera onto the TV screen and recorded the images from there…“They're part of my film now,” she says, of shadows and silhouettes blocking the view...

In response to peatland degradation by human activities worldwide, restoration through gully blocking is now being implemented in an attempt to return valuable ecological and hydrological services ...

One form of spectrum enhancement technologies for cognitive radio networks is a channel bonding strategy, with which a network user can utilize multiple idle channels as one bonding channel. In this paper, we propose an adjustable channel bonding strategy for centralized cognitive radio networks. The main idea is that the number of channels to be aggregated is set according to the number of packets remaining in the system dynamically. Based on the working principle of the proposed adjustable channel bonding strategy, we present a discrete-time priority queueing model with an adjustable transmission rate for this network system. By constructing a two-dimensional Markov chain, we give the transition probability matrix of the Markov chain and obtain the steady-state distribution of the system model. Accordingly, we derive the formulas for the blocking rate, the normalized throughput, the average latency of the Secondary Users (SUs) and the closed channel ratio. Moreover, we provide numerical experime...

To the Editor,The severe prognosis of Erdheim-Chester disease (ECD) is essentially based on central nervous system involvement and probably on cardiac injuries [1,2]. Recently, treatments blocking ...

Cost-effective radio frequency identification (RFID) transponders (tags) were investigated for wireless corrosion monitoring by applying a metal filled conductive composite coating onto the surface of the plastic tags. The coating acted as an electromagnetic interference (EMI) shield by attenuating or completely blocking the radio frequency signals transmitted between the transceiver (reader) and the tag. When the coated RFID tag was exposed to a corrosive environment through accelerated corrosion tests or marine atmospheric tests, the degradation of the coating decreased the EMI shielding effectiveness and resulted in a strengthened communication between the reader and the tag. By establishing a correlation between the corrosion rate of the metal object to be monitored and the sensor responding performance, it was possible to monitor cumulative corrosion damage via wireless sensor reading.

The electrical and optical characteristics of GaN-based light-emitting diodes (LEDs) with various kinds of electron blocking layers (EBLs) are analyzed numerically. The results indicate that an enhanced hole injection efficiency and a reduced electron leakage could be achieved with the GaN-based LED where a p-InAlGaN/GaN superlattice (SL) was employed as EBL as compared with the conventional GaN-based LEDs using rectangular p-AlGaN EBL or p-AlGaN/GaN SL EBL. Moreover, it was found that the efficiency droop could be significantly improved at high injection current density for GaN-based LEDs with p-InAlGaN/GaN SL EBL.