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Stimuli uncorrelated with reinforcement have been shown to enhance response rates and resistance to disruption; however, the effects of different rates of stimulus presentations have not been assessed. In two experiments, we assessed the effects of adding different rates of response-dependent brief stimuli uncorrelated with primary reinforcement on relative response rates and resistance to change. In both experiments, pigeons responded on variable-interval 60-s schedules of food reinforcement in two components of a multiple schedule, and brief response-dependent keylight-color changes were added to one or both components. Although relative response rates were not systematically affected in either experiment, relative resistance to presession feeding and extinction were. In Experiment 1, adding stimuli on a variable-interval schedule to one component of a multiple schedule either at a low rate (1 per min) for one group or at a high rate (4 per min) for another group similarly increased resistance to disruption in the components with added stimuli. When high and low rates of stimuli were presented across components (i.e., within subjects) in Experiment 2, however, relative resistance to disruption was greater in the component presenting stimuli at a lower rate. These results suggest that stimuli uncorrelated with food reinforcement do not strengthen responding in the same way as primary reinforcers. (Contains 7 figures.)

Introduction: TikTok has quickly gained popularity through its platforming of large amounts of short video content. Given its widespread popularity, unrestricted access and poor content monitoring may allow 3,4‐methylenedioxymethamphetamine (MDMA)‐related content to influence perception of MDMA use. We aimed to investigate how MDMA‐related videos are portrayed on TikTok and explore MDMA‐related harm reduction content. Methods: MDMA‐related hashtags and sounds were utilised to collect data from TikTok (n = 498). Video views, likes, comments and shares were recorded and quantified, and videos were coded for depiction/sentiment towards MDMA and thematic content. Results: The total sample view count was 82,413,781. Videos had a median view count of 28,900 (SD = ±561,645), median like count of 2269 (SD = ±102,904), median comment count of 52 (SD = ±755), and median share count of 34 (SD = ±3292). Most videos depicted MDMA neutrally (40.6%), while 34.9% were positive. MDMA intoxication was presumed in 40.2% of videos. The analysis produced seven themes, of which humour was the most common (80.5%). Harm reduction content was present in nine videos, viewed 999,700 times, and consisted of mixed subject matter. Discussion and Conclusions: Similar themes and issues surrounding drug‐related content on TikTok are relevant to MDMA, and intoxication was present in a significant portion of the sample. Better monitoring or regulation of content could potentially offset harm that may arise from consumption of such content. Promotion of harm reduction content could also be trialled to minimise harm. [ABSTRACT FROM AUTHOR]

This article explores the concept of "the spirit of Elijah" in the context of justice and solidarity. It suggests that the traditional interpretation of this concept, which focuses on genealogy and temple work for the dead, should be expanded to include addressing and reversing injustice in the present life. The author examines the prophetic ministry of Elijah in the historical context of economic inequality and exploitation in Israel, highlighting the connection between idolatry and oppressive social and political systems. The article also discusses the importance of standing in solidarity with those who suffer and advocating for justice on their terms. Finally, it reinterprets the prophecy of Malachi and the revelation of the priesthood by Elijah as a call to work for God's justice in the world and stand in solidarity with the oppressed. [Extracted from the article]

Working memory and attention are complex cognitive functions that are disrupted in several neuropsychiatric disorders. Mouse models of such human diseases are commonly subjected to maze-based tests that can neither distinguish between these cognitive functions nor isolate specific aspects of either function. Here, we have adapted a simple visual discrimination task, and by varying only the timing of events within the same task construct, we are able to measure independently the behavioral response to increasing attentional demand and increasing length of time that information must be maintained in working memory. We determined that mPFC lesions in mice impair attention but not working memory maintenance.

Purpose: Prostatic urethral lift with UroLift is a minimally invasive approach to treat symptomatic benign prostatic hypertrophy. This device causes artifacts on prostate magnetic resonance images. Our aim was to evaluate the impact of artifact on prostate magnetic resonance image quality. Materials and Methods: This was a single-center retrospective review of patients with UroLift who subsequently had prostate magnetic resonance imaging. Two readers graded UroLift artifact on each pulse sequence using a 5-point scale (1dnondiagnostic; 5dno artifact). Prostate Imaging Quality scores were assigned for the whole data set. The volume of gland obscured by artifact was measured. Linear and logistic regression models were used to identify predictors of poor image quality. Results: Thirty-seven patients were included. Poor image quality occurs more in the transition zone than the peripheral zone (15% vs 3%), at base/mid regions vs the apex (13%, 9%, and 5%, respectively) and on diffusion-weighted images vs T2-weighted and dynamic contrast-enhanced sequences (27%, 0.3%, 0%, respectively; P < .001). Suboptimal image quality (ie, Prostate Imaging Quality score ≤2) was found in 16%-24% of exams. The percentage of gland obscured by the UroLift artifact was higher on diffusion-weighted images and dynamic contrast-enhanced sequences than T2-weighted (32%, 9%, and 6%, respectively; P < .001). Conclusions: UroLift artifact negatively affects prostate magnetic resonance image quality with greater impact in the mid-basal transition zone, obscuring a third of the gland on diffusion-weighted images. Patients considering this procedure should be counseled on the impact of this device on image quality and its potential implications for any image-guided prostate cancer workup. [ABSTRACT FROM AUTHOR]

The present experiment developed a methodology for assessing sensitivity of conditional-discrimination performance to within-session variation of reinforcer frequency. Four pigeons responded under a multiple schedule of matching-to-sample components in which the ratio of reinforcers for correct S[subscript 1] and S[subscript 2] responses was varied across components within session. Initially, five components, each arranging a different reinforcer-frequency ratio (from 1:9 to 9:1), were presented randomly within a session. Under this condition, sensitivity to reinforcer frequency was low. Sensitivity failed to improve after extended exposure to this condition, and under a condition in which only three reinforcer-frequency ratios were varied within session. In a later condition, three reinforcer-frequency ratios were varied within session, but the reinforcer-frequency ratio in effect was differentially signaled within each component. Under this condition, values of sensitivity were similar to those traditionally obtained when reinforcer-frequency ratios for correct responses are varied across conditions. The effects of signaled vs. unsignaled reinforcer-frequency ratios were replicated in two subsequent conditions. The present procedure could provide a practical alternative to parametric variation of reinforcer frequency across conditions and may be useful in characterizing the effects of a variety of manipulations on steady-state sensitivity to reinforcer frequency. (Contains 3 figures and 1 table.)

The present case study investigated whether the tub-standing of a typically-developing toddler could be reduced by a noncontingent reinforcement procedure. The results of a brief functional analysis suggested that tub-standing was maintained by automatic reinforcement. Noncontingent reinforcement, consisting of presentation of bath toys on a fixed-time schedule, was effective in reducing the number of tub-stands per session. These results suggest that noncontingent reinforcement can be successfully applied to problem behavior in typically-developing children in naturalistic settings. (Contains 2 figures.)

This experiment assessed the effects of "d"-Amphetamine and ethanol on reinforced variable and repetitive key-peck sequences in pigeons. Pigeons responded on two keys under a multiple schedule of Repeat and Vary components. In the Repeat component, completion of a target sequence of right, right, left, left resulted in food. In the Vary component, 4-peck sequences differing from the previous 10 produced food. "d"-Amphetamine (0.1-3.0 mg/kg, i.m.) was administered in two separate phases, separated by ethanol administration (1.0-2.0 g/kg, i.g.). Under control conditions, measures of variability were high in the Vary component, and lower in the Repeat component. Following administration of the highest dose of d-amphetamine, but not ethanol, response rates decreased in both components. "d"-Amphetamine and ethanol tended to increase overall sequence variability in the Repeat component, and had less of an effect in the Vary component. Performance in the Repeat component during Phase 2 of "d"-Amphetamine administration was more disrupted than during Phase 1. Measures of variability and repetition based on shifts in the relative frequency distributions of the 16 possible key-peck sequences differed from those based on the overall measure of variability, highlighting the importance of considering both molar and molecular measures when assessing the effects of drugs on reinforced variability and repetition. In addition, the shifts in the relative frequency distribution of response sequences suggest that "d"-Amphetamine produced decrements in repeat performance by decreasing discriminative control within response sequences, whereas ethanol decreased repeat performance by decreasing discriminability between components as well as discriminative control within response sequences. (Contains 1 footnote, 1 table and 7 figures.)

Four experiments examined the effects of delays to reinforcement on key peck sequences of pigeons maintained under multiple schedules of contingencies that produced variable or repetitive behavior. In Experiments 1, 2, and 4, in the repeat component only the sequence right-right-left-left earned food, and in the vary component four-response sequences different from the previous 10 earned food. Experiments 1 and 2 examined the effects of nonresetting and resetting delays to reinforcement, respectively. In Experiment 3, in the repeat component sequences had to be the same as one of the previous three, whereas in the vary component sequences had to be different from each of the previous three for food. Experiment 4 compared postreinforcer delays to prereinforcement delays. With immediate reinforcement sequences occurred at a similar rate in the two components, but were less variable in the repeat component. Delays to reinforcement decreased the rate of sequences similarly in both components, but affected variability differently. Variability increased in the repeat component, but was unaffected in the vary component. These effects occurred regardless of the manner in which the delay to reinforcement was programmed or the contingency used to generate repetitive behavior. Furthermore, the effects were unique to prereinforcement delays. (Contains 5 tables and 8 figures.)

Previous experiments have shown that unsignaled delayed reinforcement decreases response rates and resistance to change. However, the effects of different delays to reinforcement on underlying response structure have not been investigated in conjunction with tests of resistance to change. In the present experiment, pigeons responded on a three-component multiple variable-interval schedule for food presented immediately, following brief (0.5 s), or following long (3 s) unsignaled delays of reinforcement. Baseline response rates were lowest in the component with the longest delay; they were about equal with immediate and briefly delayed reinforcers. Resistance to disruption by presession feeding, response-independent food during the intercomponent interval, and extinction was slightly but consistently lower as delays increased. Because log survivor functions of interresponse times (IRTs) deviated from simple modes of bout initiations and within-bout responding, an IRT-cutoff method was used to examine underlying response structure. These analyses suggested that baseline rates of initiating bouts of responding decreased as scheduled delays increased, and within-bout response rates tended to be lower in the component with immediate reinforcers. The number of responses per bout was not reliably affected by reinforcer delay, but tended to be highest with brief delays when total response rates were higher in that component. Consistent with previous findings, resistance to change of overall response rate was highly correlated with resistance to change of bout-initiation rates but not with within-bout responding. These results suggest that unsignaled delays to reinforcement affect resistance to change through changes in the probability of initiating a response bout rather than through changes in the underlying response structure. (Contains 1 table and 6 figures.)

Discrepant effects of drugs on behavior maintained by temporal-discrimination procedures make conclusive statements about the neuropharmacological bases of timing difficult. The current experiment examined the possible contribution of a general, drug-induced disruption of stimulus control. Four pigeons responded on a three-component multiple schedule that included a fixed-interval 2-min, temporal discrimination, and color-matching component. Under control conditions, response rates and choice responses during the first two components showed evidence of control by time, and accuracy for color matching was high in the third component. Morphine administration flattened the distribution of fixed-interval responding and produced a general disruption of accuracy in the temporal-discrimination component, whereas accuracy in the color-matching component was relatively unaffected. Analysis of the psychophysical functions from the temporal-discrimination component indicated that morphine decreased accuracy of temporal discrimination by decreasing overall stimulus control, rather than by selectively affecting timing. These results suggest the importance of determining the neurophysiological bases of stimulus control as it relates to temporal discrimination. (Contains 5 figures and 1 table.)

Recent experiments suggest that the effects of drugs of abuse on the discrimination of the passage of time may differ for experimenter-imposed and subject-produced events. The current experiment examined this suggestion by determining the effects of morphine on the discrimination of interresponse times (IRTs). Pigeons pecked a center key on a random-interval 20-s schedule of matching-to-sample trials. Once the interval had timed out, a choice trial randomly followed either a short (2- to 3-s) or long (6- to 9-s) IRT on the center key. Pecking the side key lit one color produced food after a short IRT, and pecking the side key lit the other color produced food after a long IRT. Two experimental phases differed in the functional role of the different key colors. Under control conditions, the IRT distributions had two modes, one at the lower bound of the short category and a smaller one at the lower bound of the long category. Pigeons accurately categorized the duration of the IRTs: One key color was pecked following short IRTs and the other key color was pecked following long IRTs. Morphine flattened the IRT distribution and reduced the accuracy of categorizing IRTs. Categorization of long IRTs was particularly disrupted. Morphine did not produce overestimation of time as assessed by the production or categorization of IRTs. These results are similar to those obtained previously for the effects of morphine on the discrimination of the duration of experimenter-imposed events. (Contains 1 table and 7 figures.)

Three experiments assessed the relation between the differential outcomes effect and resistance to change of delayed matching-to-sample performance. Pigeons produced delayed matching-to-sample trials by responding on variable interval schedules in two components of a multiple schedule. In the same-outcome component, the probability of reinforcement was the same for both samples (.9 in Experiments 1 and 2, .5 in Experiment 3); in the different-outcomes component, the probability of reinforcement was .9 for one sample and .1 for the other. In all three experiments, the forgetting functions in the different-outcomes component were higher and shallower than in the same-outcomes component. When total reinforcement was greater in the same-outcomes component (Experiments 1 and 2), resistance to disruption by prefeeding, intercomponent food, extinction, or flashing lights typically was greater in that component. In Experiment 3, when total reinforcement was equated, resistance to disruption was similar across components. Thus, the level and slope of forgetting functions depended on differential reinforcement correlated with the samples, but the resistance to change of forgetting functions depended on total reinforcement in a component. Both aspects of the results can be explained by a model of delayed matching to sample performance. Keywords: delayed matching to sample, differential outcome effect, probability of reinforcement, resistance to change, pigeons

I "Truth, the sum of existence... " i I - John Jaques, 1851 i [1] The way of viewing truth in the Church differs from the common philosophical concept of truth as something that corresponds to the historical or present facts of a given situation. Because this theology considers all of our experience in mortality as helping us to become like God - indeed, gods in our own right - we can therefore view God as the potentiality of humanity and creation. The revelation taught that all humankind existed in the beginning with God and Christ as intelligences - autonomous agents organized by God: "Man was also in the beginning with God. According to the current interpretation, God cannot create truth because truth is independent of God. [Extracted from the article]

Rigorous behavioral analysis is essential to the translation of research conducted using animal models of neuropsychiatric disease. Here we discuss the use of operant paradigms within our lab as a powerful approach for exploring the biobehavioral bases of disease in the maternal immune activation rat model of schizophrenia. We have investigated a range of disease features in schizophrenia including abnormal perception of time, cognition, learning, motivation, and internal state (psychosis), providing complex insights into brain and behavior. Beyond simple phenotyping, implementing sophisticated operant procedures has been effective in delineating aspects of pathological behavior, identifying interacting pathologies, and isolating contributing mechanisms of disease. We provide comment on the strengths of operant techniques to support high‐quality behavioral investigations in fundamental neuropsychiatric research. [ABSTRACT FROM AUTHOR]

An interrespone times (IRTs)-cutoff method was used to examine underlying response structure because log survivor functions of IRTs deviated from simple modes of bout initiations and within-bout responding. The analyses suggest that baseline rates of initiating bouts of responding decreased as scheduled delays increased, and within-bout response rates tended to be lower in the component with immediate reinforcers.

Background: Animal models of psychiatric diseases suffer from a lack of reliable methods for accurate assessment of subjective internal states in nonhumans. This gap makes translation of results from animal models to patients particularly challenging. Aims/methods: Here, we used the drug-discrimination paradigm to allow rats that model a risk factor for schizophrenia (maternal immune activation, MIA) to report on the subjective internal state produced by a subanesthetic dose of the N-methyl-D-aspartate (NMDA) receptor antagonist ketamine. Results/outcomes: The MIA rats' discrimination of ketamine was impaired relative to controls, both in the total number of rats that acquired and the asymptotic level of discrimination accuracy. This deficit was not due to a general inability to learn to discriminate an internal drug cue or internal state generally, as MIA rats were unimpaired in the learning and acquisition of a morphine drug discrimination and were as sensitive to the internal state of satiety as controls. Furthermore, the deficit was not due to a decreased sensitivity to the physiological effects of ketamine, as MIA rats showed increased ketamine-induced locomotor activity. Finally, impaired discrimination of ketamine was only seen at subanesthetic doses which functionally correspond to psychotomimetic doses in humans. Conclusion: These data link changes in NMDA responses to the MIA model. Furthermore, they confirm the utility of the drug-discrimination paradigm for future inquiries into the subjective internal state produced in models of schizophrenia and other developmental diseases. [ABSTRACT FROM AUTHOR]

Positron emission tomography (PET) using fluorodeoxyglucose (18F-FDG) combined with magnetic resonance imaging (MR) is an emerging hybrid modality that has shown utility in evaluating abdominal and pelvic disease entities. Together, the high soft tissue contrast and metabolic/functional imaging capabilities make this modality ideal for oncologic imaging in many organ systems. Its clinical utility continues to evolve and future research will help solidify its role in oncologic imaging. In this manuscript, we aim to (1) provide an overview of the various PET/MR systems, describing the strengths and weaknesses of each system, and (2) review the oncologic applications for 18F-FDG PET/MR in the abdomen and pelvis. [ABSTRACT FROM AUTHOR]

Experimental study is conducted to assess the effects of d-amphetamine and ethanol on reinforced variable and repetitive key-peck sequences in pigeons. It is found that d-amphetamine increased overall sequence variability in the Repeat component, and did not produce systematic stereotype in the key-peck sequences across phases in the Vary component.

A multiple schedule is used to assess how drug affect the stimulus control engendered by temporal and color samples during fixed interval. The results suggest that the effects of drugs on behavior maintained by some temporal-discrimination procedures might have little to do with the neuropharmacological correlates of timing performance but disruption of temporal discrimination by some drugs might be a result of a general decrease in stimulus control.

The experiment examined the effects of drugs abuse on the discrimination of the passage of time may differ for experimenter-imposed and subject-produced events by determining the effects of morphine on interresponse times (IRTs). The result reveals that morphine did not produce overestimation of time as assessed by the production or categorization of IRTs.

Hepatic capsular retraction is a morphologic descriptor that refers to invagination or focal flattening of the typical smooth contour of the liver capsule. It is an uncommon finding that, when combined with other imaging features and clinical context, can help to refine the differential diagnosis in patients with liver lesions. Although this descriptor has historically been used in reference to a small subset of benign and malignant lesions, the differential has since been expanded with the discovery of new entities causing capsular retraction as well as with novel and increased use of liver-directed treatment techniques. Additionally, modern imaging techniques now allow for improved detection and characterization of capsular retraction. In this review, we discuss these common and uncommon causes of capsular retraction, with an emphasis on findings from body MRI. [ABSTRACT FROM AUTHOR]

Background: Recent data indicate that kidney stone formers (KSFs) may have increased biomineralization at anatomic sites throughout the body compared with nonstone formers (NSFs). The objective of this study is to compare the volume of nonrenal systemic calcifications between KSF and NSF by using a standardized system to analyze calcifications in the abdominal aorta (AA) and splenic artery (SA). Methods: The NSF cohort was obtained from a kidney donor's prospectively maintained database. One hundred ninety-seven NSF were matched to 197 KSF based on age, gender, and body mass index. Noncontrast CT scans were evaluated and semiautomated CT software was utilized to provide an AA and SA calcification Agatston score. Wilcoxon rank-sum test was used on continuous variables and chi-squared test or Fisher's exact test on categorical variables. Odds ratios (ORs) were given for a variable's influence on the formation of stones or calcifications. Results: AA and SA calcifications were more prevalent in the KSF group (p = 0.011 and p = 0.027, respectively). KSFs were 1.9 times more likely to have intermediate or severe AA calcification than NSFs (OR = 1.9, p = 0.004). Severe AA calcifications had even a greater association (OR = 3.1, p = 0.019). KSFs were also more likely to have SA, but this did not reach statistical significance (OR = 3.7, p = 0.103). Conclusion: Patients with increased systemic calcifications, specifically aortic or splenic calcifications, may be at an increased risk for future kidney stone formation. Patients with these imaging findings and additional risk factors for stone disease may be counseled on the future risk of stones. [ABSTRACT FROM AUTHOR]

Introduction and Objectives: Studies have demonstrated associations between nephrolithiasis and systemic conditions, including low bone mineral density (BMD), which may correlate with hypercalciuria in kidney stone formers (KSFs). Traditionally, low BMD is diagnosed with dual-energy X-ray absorptiometry. As a noncontrast CT (NCCT) scan is typically part of a stone evaluation, our objective was to evaluate the association of NCCT-based vertebral BMD with 24-hour urine parameters in KSF. Materials and Methods: This is a retrospective analysis of 99 KSFs who had CT imaging and 24-hour urine studies. For each patient, BMD was estimated at the L1 vertebral body and CT attenuation measured in HU. A threshold of 160 HU was chosen to distinguish normal from low BMD. Univariate and multivariate logistic regression analysis was performed to compare patients with low and normal BMD. Multivariate linear regression was performed to assess for variables associated with 24-hour urine parameters. Results: Patients with low BMD had higher 24-hour urine calcium (219 vs 147 mg/day, p < 0.0001) and larger stone volume (259 vs 78.4 mm3, p = 0.009). Multivariate analysis demonstrated age >60 years (odds ratio [OR] 9.3, p < 0.0001) and hypercalciuria (OR 4.34, p = 0.004) correlated with low BMD. Linear regression demonstrated that lower BMD was associated with higher urinary calcium (β-coefficient −0.268, p = 0.009) and lower urinary citrate (β-coefficient 0.332, p = 0.01). Conclusions: CT-based diagnosis of low mineral bone density is associated with derangement in 24-hour urine calcium and citrate in KSFs, as well as larger stone volumes. [ABSTRACT FROM AUTHOR]

Background. In patients with reduced systolic function, the natriuretic peptide system affects heart failure (HF) progression, but the expression of key activating (corin) and degrading enzymes (neprilysin) is not well understood. Methods and Results. This pilot study (n=48) compared plasma levels of corin, neprilysin, ANP, BNP, and cGMP in control patients with normal ejection fractions (mean EF 63±3%) versus patients with systolic dysfunction, with (EF 24±8%) and without (EF 27±7%) decompensated HF (dHF), as defined by Framingham and BNP criteria. Mean ages, use of beta blockers, and ACE-inhibitors-angiotensin receptor blockers were similar between the groups. Corin levels were depressed in systolic dysfunction patients (797±346 pg/ml) versus controls (1188±549, p<0.02), but levels were not affected by dHF (p=0.77). In contrast, levels of neprilysin (p<0.01), cGMP (p<0.001), and ANP (p<0.001) were higher in systolic dysfunction patients than controls and were the highest in patients with dHF. Conclusions. Levels of neprilysin, ANP, BNP, and cGMP increased in patients with reduced systolic function and were the highest in dHF patients. Conversely, corin levels were low in patients with reduced EF with or without dHF. This pattern suggests possible enzymatic downregulation of natriuretic peptide activity in patients with reduced EF, which may have diagnostic and prognostic implications. [ABSTRACT FROM AUTHOR]