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Cyanobacteria are ubiquitous microorganisms with crucial ecosystem functions, yet most knowledge of their biology relates to aquatic taxa. We have constructed metagenomes for 50 taxonomically well-characterized terrestrial cyanobacterial cultures. These data will support phylogenomic studies of evolutionary relationships and gene content among these unique algae and their aquatic relatives.

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.

Organisms are constantly extracting information from the temporal structure of the environment, which allows them to select appropriate actions and predict impending changes.  Several lines of research have suggested that interval timing is modulated by the dopaminergic system.  It has been proposed that higher levels of dopamine cause an internal clock to speed up, whereas less dopamine causes a deceleration of the clock.  In most experiments the subjects are first trained to perform a timing task while drug free.  Consequently, most of what is known about the influence of dopaminergic modulation of timing is on well-established timing performance.  In the current study the impact of altered DA on the acquisition of temporal control was the focal question.  Thirty male Sprague-Dawley rats were distributed randomly into three different groups (haloperidol, d-amphetamine or vehicle).  Each animal received an injection 15 min prior to the start of every session from the beginning of interval training.  The subjects were trained in a Fixed Interval (FI) 16s schedule followed by training on a peak procedure in which 64s non-reinforced peak trials were intermixed with FI trials.  In a final test session all subjects were given vehicle injections and 10 consecutive non-reinforced peak trials to see if training under drug conditions altered the encoding of time.  The current study suggests that administration of drugs that modulate dopamine do not alter the encoding temporal durations but do acutely affect the initiation of responding.

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.

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.)

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.)