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Negative performance feedback is vital for stimulating employees to enhance their performance despite resulting in stress and adverse work outcomes. Fortunately, artificial intelligence (AI)‐enabled automated agents have gradually assumed certain functions led by human leaders, such as providing feedback. Drawing from regulatory focus theory, we propose that AI‐based feedback systems can serve as a "remediation" tool, effectively mitigating employees' apprehensions about receiving negative feedback. In two studies, we found that for employees who fear losing face, AI‐based negative feedback motivates promotion‐focused cognition—motivation to learn—representing a learning mechanism to promote job performance and impedes their prevention‐focused cognition—interpersonal rumination—reducing the depletion needed for job performance. These findings present novel perspectives on using AI in performance feedback. [ABSTRACT FROM AUTHOR]

The ability to learn is typically attributed to animals with brains. However, the apparently simplest form of learning, habituation, in which a steadily decreasing response is exhibited to a repeated stimulus, is found not only in animals but also in single-cell organisms and individual mammalian cells. Habituation has been codified from studies in both invertebrate and vertebrate animals as having ten characteristic hallmarks, seven of which involve a single stimulus. Here, we show by mathematical modeling that simple molecular networks, based on plausible biochemistry with common motifs of negative feedback and incoherent feedforward, can robustly exhibit all single-stimulus hallmarks. The models reveal how the hallmarks arise from underlying properties of timescale separation and reversal behavior of memory variables, and they reconcile opposing views of frequency and intensity sensitivity expressed within the neuroscience and cognitive science traditions. Our results suggest that individual cells may exhibit habituation behavior as rich as that which has been codified in multi-cellular animals with central nervous systems and that the relative simplicity of the biomolecular level may enhance our understanding of the mechanisms of learning. [Display omitted] • Habituation is a form of learning characterized by specific hallmarks • Biochemically plausible models exhibit all single-stimulus hallmarks • Timescale separation and reversal behavior underlie the hallmarks • Models reconcile opposing views from neuroscience and cognitive science Eckert et al. study mathematical models of habituation, the simplest learning behavior, in single cells. They find that biochemically plausible networks based on negative feedback or incoherent feedforward motifs satisfy all single-stimulus hallmarks of habituation, as codified in animals with brains. [ABSTRACT FROM AUTHOR]

Background: Sleep loss has sometimes catastrophic effects on risky decision-making. However, it is unknown to what extent such deficits are exacerbated with increasing duration of sleep deprivation (SD) and whether sustained vigilant attention mediates this sleep deprivation-induced deficit. Methods: The present study aimed to investigate the effect of 36 hours of SD on 37 male college students' arousal, emotion, vigilant attention, and risky decision-making, using the Psychomotor Vigilance Test, the Game of Dice Task, and scales assessing fatigue, sleep, and emotions. Results: Compared to baseline, SD significantly increased sleepiness, fatigue, and negative emotions, decreased positive emotions and vigilant attention, and led to a shift toward risky decision-making, and these effects often appeared 15 or 20 hours after SD. Interestingly, participants' ability to employ positive feedback was maintained, whereas their performance to utilize negative feedback was impaired even after 8 hours of sleep deprivation. Meanwhile, vigilant attention acted as a mediator between SD and risky decision-making (z = -1.97, 95% [-6.00, -0.30]). Discussion: These results suggest that sleep-deprived individuals are unable to use negative feedback to optimize their judgments, which may account for their poor decision-making under risk. [ABSTRACT FROM AUTHOR]

Cognitive flexibility, the capacity to adapt behaviour to changes in the environment, is impaired in a range of brain disorders, including schizophrenia and Parkinson's disease. Putative neural substrates of cognitive flexibility include mesencephalic pathways to the ventral striatum (VS) and dorsomedial striatum (DMS), hypothesized to encode learning signals needed to maximize rewarded outcomes during decision‐making. However, it is unclear whether mesencephalic projections to the ventral and dorsal striatum are distinct in their contribution to flexible reward‐related learning. Here, rats acquired a two‐choice spatial probabilistic reversal learning (PRL) task, reinforced on an 80%|20% basis (correct|incorrect responses) that assessed the flexibility of behaviour to repeated reversals of response‐outcome contingencies. We report that optogenetic stimulation of projections from the ventral tegmental area (VTA) to the nucleus accumbens shell (NAcS) in the VS significantly impaired reversal learning when optical stimulation was temporally aligned with negative feedback (i.e., reward omission). VTA → NAcS stimulation during other phases of the behavioural task was without significant effect. Optogenetic stimulation of projection neurons from the substantia nigra (SN) to the DMS, aligned either with reward receipt or omission or prior to making a choice, had no significant effect on reversal learning. These findings are consistent with the notion that increased activity in the VTA → NAcS pathway disrupts behavioural flexibility by impairing learning from negative reinforcement. [ABSTRACT FROM AUTHOR]

Feedback at the photoreceptor synapse is the first neuronal circuit computation in vision, which influences downstream activity patterns within the visual system. Yet, the identity of the feedback signal and the mechanism of synaptic transmission are still not well understood. Here, we combined perturbations of cell-type-specific genes of mouse horizontal cells with two-photon imaging of the result of light-induced feedback in cones and showed that the electrogenic bicarbonate transporter Slc4a5, but not the electroneutral bicarbonate transporter Slc4a3, both expressed specifically in horizontal cells, is necessary for horizontal cell-to-cone feedback. Pharmacological blockage of bicarbonate transporters and buffering pH also abolished the feedback but blocking sodium-proton exchangers and GABA receptors did not. Our work suggests an unconventional mechanism of feedback at the first visual synapse: changes in horizontal cell voltage modulate bicarbonate transport to the cell, via Slc4a5, which leads to the modulation of feedback to cones. [Display omitted] • Feedback from horizontal cells to cones was measured by imaging calcium in cones • Slc4a5 is an electrogenic Na+-HCO 3 − cotransporter specific to horizontal cells • Knocking out or down Slc4a5 abolished horizontal cell-to-cone feedback • Blocking HCO 3 − transporters and buffering pH also abolished feedback Molecular mechanisms of horizontal cell-to-cone feedback in the retina have been under debate. Morikawa et al. show that Slc4a5, an electrogenic sodium-bicarbonate cotransporter specific to horizontal cells, is crucial for feedback. They suggest that Slc4a5, through its voltage-dependent transport of bicarbonate, regulates pH in the synaptic cleft that mediates feedback. [ABSTRACT FROM AUTHOR]

Cushing's syndrome is characterized by chronic glucocorticoid oversecretion and diverse clinical manifestations. Distinguishing between adrenocorticotropic hormone (ACTH)‐independent and ACTH‐dependent forms is crucial for determining treatment options. Plasma ACTH levels aid in the differential diagnosis, with undetectable or low levels suggesting ACTH‐independent hypercortisolemia. ACTH is derived from pro‐opiomelanocortin, and its processing involves prohormone convertase 1/3. High‐molecular‐weight ACTH is generally found in ACTH‐producing pituitary tumors and ectopic ACTH syndrome. The mechanism of negative feedback and the process of high‐molecular‐weight ACTH alternation during ACTH‐independent Cushing's syndrome remain unclear. A 40‐year‐old woman with hypertension and multiple fractures developed symptoms suggestive of Cushing's syndrome. Computed tomography revealed a left adrenocortical tumor along with atrophy of the right adrenal gland. ACTH levels were undetectable at the previous clinic, indicating ACTH‐independent Cushing's syndrome. However, subsequent measurements at our hospital revealed non‐suppressed ACTH (18.1 pg/mL), prompting further investigation. Gel exclusion chromatography confirmed the presence of high‐molecular‐weight ACTH. Metyrapone treatment decreased the cortisol levels. In this situation, in which ACTH levels should be elevated, a decrease in high‐molecular‐weight ACTH levels was observed. Histological findings revealed cortisol‐producing adenoma without ACTH expression. This case highlights the importance of assay differences in evaluating ACTH concentrations and introduces a novel finding of circulating high‐molecular‐weight ACTH. The observed decline in high‐molecular‐weight ACTH levels suggests a potential time lag in the negative feedback within the hypothalamic–pituitary–adrenal axis exhibited by glucocorticoids. This temporal aspect of the regulation of ACTH‐related molecules warrants further exploration to enhance our understanding of the hypothalamic–pituitary–adrenal axis feedback mechanism. [ABSTRACT FROM AUTHOR]

Retinoic acid is crucial for vertebrate embryogenesis, influencing anterior‐posterior patterning and organogenesis through its interaction with nuclear hormone receptors comprising heterodimers of retinoic acid receptors (RARα, β, or γ) and retinoid X receptors (RXRα, β, or γ). Tissue retinoic acid levels are tightly regulated since both its excess and deficiency are deleterious. Dehydrogenase/reductase 3 (DHRS3) plays a critical role in this regulation by converting retinaldehyde to retinol, preventing excessive retinoic acid formation. Mutations in DHRS3 can result in embryonic lethality and congenital defects. This study shows that mouse Dhrs3 expression is responsive to vitamin A status and is directly regulated by the RAR/RXR complex through cis‐regulatory elements. This highlights a negative feedback mechanism that ensures retinoic acid homeostasis. [ABSTRACT FROM AUTHOR]

Abstract The discrepancy between model predictions and actual processes, known as process-model mismatch (PMM), remains a substantial challenge in bioprocess optimization. We previously introduced a hybrid in silico/in-cell controller (HISICC) that combines model-based optimization with cell-based feedback to address this problem. Here, we extended this approach to regulate a key enzyme level using intracellular biosensing. The extended HISICC was implemented using an Escherichia coli strain engineered for fatty acid production (FA3). This strain contains a genetically encoded feedback controller that decelerates the expression of acetyl-CoA carboxylase (ACC) in response to malonyl-CoA synthesized through the enzymatic reaction. We modeled FA3 to allow the HISICC to optimize an inducer input that accelerates the enzyme expression. Simulations showed that the HISICC slowed the unexpectedly rapid accumulation of ACC resulting from PMMs before it reached cytotoxic levels, thereby improving fatty acid yields. These results highlight the potential of our approach, particularly in cases where monitoring intracellular biomolecules is required to handle PMMs.

Niche-derived growth factors support self-renewal of mouse spermatogonial stem and progenitor cells through ERK MAPK signaling and other pathways. At the same time, dysregulated growth factor-dependent signaling has been associated with loss of stem cell activity and aberrant differentiation. We hypothesized that growth factor signaling through the ERK MAPK pathway in spermatogonial stem cells is tightly regulated within a narrow range through distinct intracellular negative feedback regulators. Evaluation of candidate extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK)-responsive genes known to dampen downstream signaling revealed robust induction of specific negative feedback regulators, including Spry4, in cultured mouse spermatogonial stem cells in response to glial cell line-derived neurotrophic factor or fibroblast growth factor 2. Undifferentiated spermatogonia in vivo exhibited high levels of Spry4 mRNA. Quantitative single-cell analysis of ERK MAPK signaling in spermatogonial stem cell cultures revealed both dynamic signaling patterns in response to growth factors and disruption of such effects when Spry4 was ablated, due to dysregulation of ERK MAPK downstream of RAS. Whereas negative feedback regulator expression decreased during differentiation, loss of Spry4 shifted cell fate toward early differentiation with concomitant loss of stem cell activity. Finally, a mouse Spry4 reporter line revealed that the adult spermatogonial stem cell population in vivo is demarcated by strong Spry4 promoter activity. Collectively, our data suggest that negative feedback-dependent regulation of ERK MAPK is critical for preservation of spermatogonial stem cell fate within the mammalian testis.

The relevance of student evaluation of teaching (SET) for both development of individual teaching as well as for institutional quality management in higher education (HE) contexts has been investigated in numerous studies. However, how educators incorporate students’ feedback into their teaching, especially in the case of negative evaluations, depends on how educators perceive and deal with students’ feedback. To address this issue, we conducted an experimental vignette study to document how university teachers (N = 107) respond to negative SET at cognitive, emotional, and behavioral levels. Further, we varied the focus (student- vs. teacher-oriented) and the content (learning outcomes, interest in course, and learning activities) of feedback messages in the vignettes. Our results show that students’ negative feedback, especially concerning learning outcomes, evoked predominantly negative emotions of sadness or anxiety in HE teachers. Further, participants perceived the students’ negative feedback as moderately unstable and as to some extent limited within their control. Student-oriented negative comments regarding students’ interest in course or students’ engagement in learning activities were interpreted as more trustworthy and valid than negative feedback on teacher-focused characteristics related to the educators’ instructional competences. On average the participants indicated higher approach tendencies than avoidance tendencies after receiving students’ negative feedback. Finally, how HE teachers perceived and dealt with negative SET was linked to teachers’ perceived value of students’ feedback. Our findings underline the importance of incorporating more student-focused elements into SET and introducing activities that assist HE teachers in handling negative feedback within the SET process. [ABSTRACT FROM AUTHOR]

TORC1 (target of rapamycin complex 1) is a highly conserved protein kinase that plays a central role in regulating cell growth. Given the role of mammalian TORC1 (mTORC1) in metabolism and disease, understanding mTORC1 downstream signaling and feedback loops is important. mTORC1 recognizes some of its substrates via a five amino acid binding sequence called the TOR signaling (TOS) motif. mTORC1 binding to a TOS motif facilitates phosphorylation of a distinct, distal site. Here, we show that LST2, also known as ZFYVE28, contains a TOS motif (amino acids 401 to 405) and is directly phosphorylated by mTORC1 at serine 670 (S670). mTORC1-mediated S670 phosphorylation promotes LST2 monoubiquitination on lysine 87 (K87). Monoubiquitinated LST2 is stable and displays a broad reticular distribution. When mTORC1 is inactive, unphosphorylated LST2 is degraded by the proteasome. The absence of LST2 enhances EGFR (epidermal growth factor receptor) signaling. We propose that mTORC1 negatively feeds back on its upstream receptor EGFR via LST2. [ABSTRACT FROM AUTHOR]

This study examined the role of positive and negative feedback on goal commitment and energy investment among English as a foreign language learners who experienced directed motivational currents (DMCs). To this purpose, a systematic methodology was used to identify language learners with a DMC experience (six students, four females, two males, mean of age = 19.5). Semi-structured interviews were conducted with the participants. The results of qualitative content analysis indicated that the three key features of DMCs were found in participants' motivational experiences. In addition, the results showed that positive feedback affected goal commitment in DMCs by increasing goal persistence and sense of self-efficacy, while negative feedback enhanced motivation in DMCs by reducing the discrepancy between current state with the well-defined target state. The results also showed that feedback had some affective consequences that influenced goal pursuit in DMCs. [ABSTRACT FROM AUTHOR]

Despite widespread and striking examples of physiological oscillations, their functional role is often unclear. Even glycolysis, the paradigm example of oscillatory biochemistry, has seen questions about its oscillatory function. Here, we take a systems approach to argue that oscillations play critical physiological roles, such as enabling systems to avoid desensitization, to avoid chronically high and therefore toxic levels of chemicals, and to become more resistant to noise. Oscillation also enables complex physiological systems to reconcile incompatible conditions such as oxidation and reduction, by cycling between them, and to synchronize the oscillations of many small units into one large effect. In pancreatic β-cells, glycolytic oscillations synchronize with calcium and mitochondrial oscillations to drive pulsatile insulin release, critical for liver regulation of glucose. In addition, oscillation can keep biological time, essential for embryonic development in promoting cell diversity and pattern formation. The functional importance of oscillatory processes requires a re-thinking of the traditional doctrine of homeostasis, holding that physiological quantities are maintained at constant equilibrium values, a view that has largely failed in the clinic. A more dynamic approach will initiate a paradigm shift in our view of health and disease. A deeper look into the mechanisms that create, sustain and abolish oscillatory processes requires the language of nonlinear dynamics, well beyond the linearization techniques of equilibrium control theory. Nonlinear dynamics enables us to identify oscillatory ('pacemaking') mechanisms at the cellular, tissue and system levels.

BackgroundSleep loss has sometimes catastrophic effects on risky decision-making. However, it is unknown to what extent such deficits are exacerbated with increasing duration of sleep deprivation (SD) and whether sustained vigilant attention mediates this sleep deprivation-induced deficit.MethodsThe present study aimed to investigate the effect of 36 hours of SD on 37 male college students’ arousal, emotion, vigilant attention, and risky decision-making, using the Psychomotor Vigilance Test, the Game of Dice Task, and scales assessing fatigue, sleep, and emotions. ResultsCompared to baseline, SD significantly increased sleepiness, fatigue, and negative emotions, decreased positive emotions and vigilant attention, and led to a shift toward risky decision-making, and these effects often appeared 15 or 20 hours after SD. Interestingly, participants’ ability to employ positive feedback was maintained, whereas their performance to utilize negative feedback was impaired even after 8 hours of sleep deprivation. Meanwhile, vigilant attention acted as a mediator between SD and risky decision-making (z = -1.97, 95% [-6.00, -0.30]).DiscussionThese results suggest that sleep-deprived individuals are unable to use negative feedback to optimize their judgments, which may account for their poor decision-making under risk.

Abstract During growth phase, antlers exhibit a very rapid rate of chondrogenesis. The antler is formed from its growth center reserve mesenchyme (RM) cells, which have been found to be the derivatives of paired related homeobox 1 (Prrx1)-positive periosteal cells. However, the underlying mechanism that drives rapid chondrogenesis is not known. Herein, the miRNA expression profiles and chromatin states of three tissue layers (RM, precartilage, and cartilage) at different stages of differentiation within the antler growth center were analyzed by RNA-sequencing and ATAC-sequencing. We found that miR-140-3p was the miRNA that exhibited the greatest degree of upregulation in the rapidly growing antler, increasing from the RM to the cartilage layer. We also showed that Prrx1 was a key upstream regulator of miR-140-3p, which firmly confirmed by Prrx1 CUT&Tag sequencing of RM cells. Through multiple approaches (three-dimensional chondrogenic culture and xenogeneic antler model), we demonstrated that Prrx1 and miR-140-3p functioned as reciprocal negative feedback in the antler growth center, and downregulating PRRX1/upregulating miR-140-3p promoted rapid chondrogenesis of RM cells and xenogeneic antler. Thus, we conclude that the reciprocal negative feedback between Prrx1 and miR-140-3p is essential for balancing mesenchymal proliferation and chondrogenic differentiation in the regenerating antler. We further propose that the mechanism underlying chondrogenesis in the regenerating antler would provide a reference for helping understand the regulation of human cartilage regeneration and repair.

Opposite dynamics are behind natural selection and sexual selection. When considering natural and sexual selection separately, the fittest individuals survive. However, when these processes interact, luck often determines the survivor. As a result, chance has a greater impact on evolution. [ABSTRACT FROM AUTHOR]

The menstrual cycle of fertile female is regulated by multiple organs and hormones, controlling the reproductive health and fertility of females. This paper is dedicated to exploring how two negative feedback loops regulate and influence the dynamic behavior of the menstrual cycle. We simplified the regulation circuit of the menstrual cycle into a nonlinear differential equation with two time delays. This simplified mathematical model integrates the hypothalamus–pituitary–ovary primary negative feedback loop and the negative feedback auxiliary loop between the ovary and the pituitary. We investigated the delay-dependent conditions for the stability of the model’s equilibrium points and also demonstrated the presence of Hopf bifurcations. Theoretical analysis suggests that the primary feedback loop is the major factor driving oscillation in the system. Further numerical simulations indicate that the negative feedback auxiliary loop allows the system to adjust its amplitude while maintaining the robustness of the cycle length. Consequently, the results obtained from this model provide new insights into the regulation of oscillations in menstrual cycle irregularities. [ABSTRACT FROM AUTHOR]

Emotion-regulation goals are often studied in isolation, despite them typically occurring in the presence of alternative goals. Negative feedback situations offer an intriguing context to study the interplay of emotionregulation goals (wanting to feel better) and performance goals (wanting to perform better). Across five preregistered online studies (N= 1,087), we investigated emotion-regulation choice (i.e., whether and how to regulate) in feedback situations. Challenging the assumption that the goal to perform better is the focal goal in negative-feedback situations, we show that negative feedback increases the salience of the goal to feel better via negative affect in Studies 1-2. Moving beyond the question of whether people regulate their emotions when they receive negative feedback, we examined how they regulate their emotions in Studies 3-5. Focusing on the relative importance of the goals to feel and to perform better, we found that the goal to perform better but not the goal to feel better influences negative-feedback recipients' emotion-regulation strategy choice. A salient goal to perform better was associated with a preference for reappraisal over distraction. These results have critical implications for the emotion-regulation literature and models of feedback processing from an emotion-regulation perspective. They demonstrate that affect-oriented processes such as emotion regulation operate when people receive negative feedback. They also highlight the importance of studying alternative goals given their relevance for how people regulate their emotions. From a practical standpoint, the findings may help us to better understand why people sometimes fail to perform better following negative feedback. [ABSTRACT FROM AUTHOR]

SUMMARY: Negative feedback can induce adverse responses. This is problematic in auditing as negative feedback is common during workpaper reviews, and auditors' follow-through on this feedback is essential to staff development and audit quality. Psychology research suggests supervisors' framing of feedback can impact subordinates' feedback reactions and subsequent performance, and this effect might vary depending on their relative receptivity to feedback (i.e., feedback orientation). In a 2 × 2 between-subjects experiment, using a review notes task, I examine the joint influence of these factors and find divergent effects. Results show novice auditors with stronger feedback orientations have more positive reactions to negative feedback when reviewers emphasize learning goals, but framing does not influence performance. However, those with weaker feedback orientations react poorly regardless of framing, but learning goals improve their performance. These results enhance understanding of effects of goal framing on audit quality and help guide reviewers on how to frame negative feedback. JEL Classifications: M40; M42. [ABSTRACT FROM AUTHOR]

Long-term series of annual and seasonal water flow and major ions in the Pechora River were analyzed. Long-term phases of increased and decreased water flow were identified, ranging in duration from 11 to 49 years, and the major characteristics of these phases were determined. Changes in the sequence and boundaries of contrast phases in the annual and snowmelt spring–summer flood runoff were found to coincide. The difference between the mean seasonal water runoff during the phases of increased and decreased flow varied from 12 to 41%. The ion flow values of contrast phases typically differed by 9 to 36%, which is less than for water flow. This is due to the inverse dependence between ion concentrations and water discharge. Such peculiar negative feedback stabilizes the rates of chemical denudation in the river catchments to some extent and, thus, the discharge of major ions into seas, even during significant variations in water. [ABSTRACT FROM AUTHOR]

During growth phase, antlers exhibit a very rapid rate of chondrogenesis. The antler is formed from its growth center reserve mesenchyme (RM) cells, which have been found to be the derivatives of paired related homeobox 1 (Prrx1)-positive periosteal cells. However, the underlying mechanism that drives rapid chondrogenesis is not known. Herein, the miRNA expression profiles and chromatin states of three tissue layers (RM, precartilage, and cartilage) at different stages of differentiation within the antler growth center were analyzed by RNA-sequencing and ATAC-sequencing. We found that miR-140-3p was the miRNA that exhibited the greatest degree of upregulation in the rapidly growing antler, increasing from the RM to the cartilage layer. We also showed that Prrx1 was a key upstream regulator of miR-140-3p, which firmly confirmed by Prrx1 CUT&Tag sequencing of RM cells. Through multiple approaches (three-dimensional chondrogenic culture and xenogeneic antler model), we demonstrated that Prrx1 and miR-140-3p functioned as reciprocal negative feedback in the antler growth center, and downregulating PRRX1/upregulating miR-140-3p promoted rapid chondrogenesis of RM cells and xenogeneic antler. Thus, we conclude that the reciprocal negative feedback between Prrx1 and miR-140-3p is essential for balancing mesenchymal proliferation and chondrogenic differentiation in the regenerating antler. We further propose that the mechanism underlying chondrogenesis in the regenerating antler would provide a reference for helping understand the regulation of human cartilage regeneration and repair. [ABSTRACT FROM AUTHOR]

Living systems have developed control mechanisms for achieving homeostasis. Here, we propose a plausible biological feedback architecture that exploits ultrasensitivity and shows adaptive responses without requiring error detection mechanism (i.e., by measuring an external reference signal and deviation from this). While standard engineering control systems are usually based on error measurements, this is not the case for biological systems. We find that a two-state negative feedback control system, without explicit error measurements, is able to track a reference signal that is implicitly determined by the tunable threshold and slope characterizing the sigmoidal ultrasensitive relationship implemented by the control system. We design different ultrasensitive control functions (ultrasensitive up- or down-regulation, or both) and, by performing sensitivity analysis, show that increasing the sensitivity level of the control allows achieving robust adaptive responses to the effects of parameter variations and step disturbances. Finally, we show that the devised control system architecture without error detection is implemented within the yeast osmoregulatory response network and allows achieving adaptive responses to osmotic stress, by exploiting the ubiquitous ultrasensitive features of the involved biomolecular circuitry. [ABSTRACT FROM AUTHOR]

Drawing on attention capacity theory, we proposed a nonlinear relationship between supervisor negative feedback and subordinate job performance, while subordinate work concentration will non-linearly mediate, and leader-member exchange (LMX) will moderate, this relationship. Using cross-sectional (N = 234, Study 1) and three-wave data (N = 327, Study 2) from employee-supervisor dyads, we found that supervisor negative feedback had a significant inverted-U relationship with subordinate job performance. Furthermore, subordinate work concentration non-linearly mediated this relationship. Additionally, the results revealed that such curvilinear patterns only exist when LMX was low. Finally, the theoretical and managerial implications of our findings were discussed. [ABSTRACT FROM AUTHOR]

In this paper, a novel wideband low noise amplifier (LNA) operating in the 9–23 GHz frequency range is presented. The proposed LNA design utilizes a combination technique consisting of pole‐tuning technique, shunt resistive‐capacitor negative feedback, and gate‐capacitive peaking technique to achieve significant bandwidth extension while maintaining acceptable overall performance. For verification, a one‐stage triple‐stacked LNA using the combination technique is designed and implemented in a 0.18‐μm SiGe BiCMOS heterojunction bipolar transistor (HBT) process. The fabricated prototype demonstrates a peak gain of 13.8 dB at 19.5 GHz, minimum noise figure of 3.1 dB at 14 GHz, 3‐dB bandwidth of 14 GHz, and a fractional bandwidth of 87.5%, while consuming a dc power of 39.6 mW. Moreover, the chip occupies a small silicon area of 0.39 mm2 including all testing pads with a core size of only 0.192 mm2. [ABSTRACT FROM AUTHOR]

Abstract Introduction While feedback aims to support learning, students frequently struggle to use it. In studying feedback responses there is a gap in explaining them in relation to learning theory. This study explores how feedback experiences influence medical students’ self-regulation of learning. Methods Final-year medical students across three campuses (Ireland, Bahrain and Malaysia) were invited to share experiences of feedback in individual semi-structured interviews. The data were thematically analysed and explored through the lens of self-regulatory learning theory (SRL). Results Feedback interacts with learners’ knowledge and beliefs about themselves and about learning. They use feedback to change both their cognitive and behavioural learning strategies, but how they choose which feedback to implement is complex. They struggle to generate learning strategies and expect teachers to make sense of the “how” in addition to the “what”” in planning future learning. Even when not actioned, learners spend time with feedback and it influences future learning. Conclusion By exploring our findings through the lens of self-regulation learning, we advance conceptual understanding of feedback responses. Learners’ ability to generate “next steps” may be overestimated. When feedback causes negative emotions, energy is diverted from learning to processing distress. Perceived non-implementation of feedback should not be confused with ignoring it; feedback that is not actioned often impacts learning.

Using the example of an electron source with a plasma cathode based on a low-pressure arc discharge with grid stabilization of the cathode/emission plasma boundary and an open anode/beam plasma boundary, a mechanism is described for increasing the electrical strength of a high-voltage accelerating gap by introducing a series negative current feedback (NCF) in the accelerating interval, which makes it possible to level out uncontrolled bursts of the beam current during its pulse. The introduction of NCF is achieved by using a special electrode in the space of the plasma emitter connected through a resistance to the anode of the arc discharge, and the main task of which is to intercept accelerated ions penetrating into the emitter from the high-voltage accelerating gap, due to which the current of electron emission from the arc discharge plasma decreases by a value proportional to the ion current in the accelerating gap. Since most sources and accelerators of electrons with plasma cathodes based on discharges of various types have a similar principle of operation, the use of this method will not only expand the limiting parameters of the generated electron beams, but also increase the stability of the operation of such electron sources, and, accordingly, beam irradiation of various materials and products. [ABSTRACT FROM AUTHOR]

This research aims to gain a better understanding of the critical role that teachers play in explaining why pupils are motivated to learn. This can help students explore information and new concepts in settings in which they feel competent and motivated. The term motivation according to Gardner and Lambert (1972) indicates motivation as a "desire to achieve a goal, effort expended, and attitudes to learning a language". Therefore, their motivation has a direct influence on the effort they put in and on their academic outcome. Understanding what motivates students well could encourage teachers to decide the best methods to educate their students and how to put those methods into practice. This study provides insight into how English teachers who have been teaching for several years see the impact of motivation on language learning and what they think they can do as language teachers to motivate their students. The main aims and focus of this study were to find out what motivates EFL students and factors that affect their motivation. [ABSTRACT FROM AUTHOR]

In this study, we investigate the temperature-dependent electrical characteristics of bistable silicon resistors (biristors) at temperatures ranging from 275 to 400 K. The proposed biristor exhibits low latch voltages owing to the surface accumulation layer transistor concept. Moreover, the biristor was abruptly turned on and off by positive and negative feedback phenomena, respectively. As the temperature increased from 275 to 400 K, the latch-up voltage decreased from 2.131 to 1.696 V, while the latch-down voltage increased from 1.486 to 1.637 V. Mechanisms of temperature-dependent change in latch voltage were analyzed using energy band diagrams. This temperature-dependent analysis on silicon biristor can serve as blueprint for the contribution of stable operation. [ABSTRACT FROM AUTHOR]

Introduction: While feedback aims to support learning, students frequently struggle to use it. In studying feedback responses there is a gap in explaining them in relation to learning theory. This study explores how feedback experiences influence medical students' self-regulation of learning. Methods: Final-year medical students across three campuses (Ireland, Bahrain and Malaysia) were invited to share experiences of feedback in individual semi-structured interviews. The data were thematically analysed and explored through the lens of self-regulatory learning theory (SRL). Results: Feedback interacts with learners' knowledge and beliefs about themselves and about learning. They use feedback to change both their cognitive and behavioural learning strategies, but how they choose which feedback to implement is complex. They struggle to generate learning strategies and expect teachers to make sense of the "how" in addition to the "what"" in planning future learning. Even when not actioned, learners spend time with feedback and it influences future learning. Conclusion: By exploring our findings through the lens of self-regulation learning, we advance conceptual understanding of feedback responses. Learners' ability to generate "next steps" may be overestimated. When feedback causes negative emotions, energy is diverted from learning to processing distress. Perceived non-implementation of feedback should not be confused with ignoring it; feedback that is not actioned often impacts learning. [ABSTRACT FROM AUTHOR]

The paper presents the results of the study of the influence of symmetry in the design of bit-stream digital converters. We have shown realizations of the symmetry-based approach at different levels: at the level of basic elements, functional converters, and at the level of processes occurring in bit-streaming devices. Using symmetry in design, we have developed basic bit-stream elements that realize frequently used transformations with good technical performance. As a research result, we present descriptions and implementation results of the designed symmetric bit-stream devices in FPGA chips. Using the proposed elements and the concept of symmetric bit-stream device design, we designed and presented a specialized computing module for a temperature sensor controller. [ABSTRACT FROM AUTHOR]

We study the scalar difference equation \[x(k+1) = x(k) + \frac{f(x(k-N))}{N},\] where \(f\) is nonincreasing with negative feedback. This equation is a discretization of the well-studied differential delay equation \[x'(t) = f(x(t-1)).\] We examine explicit families of such equations for which we can find, for infinitely many values of $ and appropriate parameter values, various dynamical behaviors including periodic solutions with large numbers of sign changes per minimal period, solutions that do not converge to periodic solutions, and chaos. We contrast these behaviors with the dynamics of the limiting differential equation. Our primary tool is the analysis of return maps for the difference equations that are conjugate to continuous self-maps of the circle.

Research shows that negative or threatening emotional stimuli can foster movement velocity and force. However, less is known about how evaluative threat may influence movement parameters in endurance exercise. Based on social self-preservation theory, the authors predicted that evaluative threat would facilitate effort expenditure in physical exercise. In an exploratory study, 27 young men completed a bogus intelligence test and received either low-intelligence-quotient feedback (evaluative threat) or no feedback (control). Next, they were asked to pedal on a stationary bicycle for 30 min at a constant cadence. After 10 min (calibration period), the cadence display was hidden. Findings show that participants under evaluative threat increased cadence more than control participants during the subsequent 20-min critical period. These findings underline the potential importance of unrelated evaluative threat on physical performance. [ABSTRACT FROM AUTHOR]

ABSTRACTThe archetypal PhoQP two-component system from Enterobacteria regulates pathways like magnesium homeostasis in Escherichia coli and virulence factor expression in Salmonella enterica. We had previously reported that E. coli rapidly accumulated mutations in the mgrB gene, a negative feedback regulator of PhoQP, when evolved in the antibiotic trimethoprim. Here, we first show that trimethoprim-selected mutations in mgrB either lower its expression or alter the C-terminus of the MgrB protein and prevent interaction with PhoQ. Both mechanisms compromise MgrB activity, leading to PhoQP hyperactivation and overexpression of dihydrofolate reductase (folA), which is the target of trimethoprim. We then investigate the consequences of deregulating PhoQP for the fitness of E. coli and elucidate the underlying mechanisms. Using laboratory evolution, we demonstrate that mgrB mutations facilitate rapid fixation of resistant bacteria in populations evolving in trimethoprim, even though their independent effect on drug IC50 is nominal. This effect is explained by a pervasive transcriptional response to deregulated PhoQP, specifically on the downstream RstA-regulon, in addition to activating folA transcription. Pervasive gene deregulation also explained the fitness costs of mgrB mutations, although involving different molecular players. PhoQP hyperactivation perturbed the balance of RpoS- and RpoD-regulated transcriptional programs and mutations that reset this balance-restored bacterial fitness in antibiotic-free conditions. Our study shows that the deregulation of a single signaling pathway permeates the wider gene expression network and leads to adaptation or maladaptation depending on the environmental context. The implications of our findings for the evolution of feedback mechanisms in two-component signaling are discussed.IMPORTANCEBacteria employ a number of mechanisms to adapt to antibiotics. Mutations in transcriptional regulators alter the expression levels of genes that can change the susceptibility of bacteria to antibiotics. Two-component signaling proteins are a major class of signaling molecule used by bacteria to regulate transcription. In previous work, we found that mutations in MgrB, a feedback regulator of the PhoQP two-component system, conferred trimethoprim tolerance to Escherichia coli. Here, we elucidate how mutations in MgrB have a domino-like effect on the gene regulatory network of E. coli. As a result, pervasive perturbation of gene regulation ensues. Depending on the environmental context, this pervasive deregulation is either adaptive or maladaptive. Our study sheds light on how deregulation of gene expression can be beneficial for bacteria when challenged with antibiotics, and why regulators like MgrB may have evolved in the first place.

In this article, we mainly consider the dynamic analysis of a stochastic infectious disease model with negative feedback, a symmetric and compatible distribution family. Based on the sir epidemic model taking into account the isolation (y) and the death (v), we consider adding a new variable (w) to control the information of non-drug interventions, which measures transformations in isolation performance that determine the epidemic, and establish a new model. We have demonstrated various properties of the model solution using Lyapunov functions for this model. To begin with, we demonstrate the existence and uniqueness of the global positive solution. After that, we obtained the conditions that need to be met for the extinction of the disease and verified the correctness of the conclusion by simulating numerical values. Afterwards, we prove the stochastic boundedness and stationary distribution of the model solution. [ABSTRACT FROM AUTHOR]

Individuals with grandiose narcissism exhibit enhanced antagonism and a defensive pattern of discordance between their emotional and physiological reactions to self‐threatening evaluations. Although theoretical perspectives link narcissistic defensiveness to negative emotions, empirical evidence linking grandiose narcissism to emotional reactivity remains mixed. The current study used self‐reported affect, electrocardiography, and facial electromyography (fEMG) to examine whether people scoring high in grandiose narcissism show amplified physiological and self‐reported emotional reactivity to negative social evaluation. Following two challenging cognitive tasks, participants received negative and neutral feedback in a face‐to‐face evaluation situation. Receiving negative feedback decreased self‐reported positive affect and dominance, slowed heart rate, and amplified fEMG activity related to frowning and eye constriction. Although self‐reported emotional reactions were unrelated to grandiose narcissism, fEMG activity associated with negative affect was significantly enhanced by grandiose narcissism. In conclusion, individuals with higher levels of grandiose narcissism may not be willing to report overt emotional reactivity to self‐threatening feedback, but physiological responses "beneath their thin skin" reveal amplified threat‐related facial muscle activity suggestive of a negative emotional state. Although grandiose narcissism is often linked with strong negative emotional reactions to social evaluations, direct evidence of the reactions remains mixed. We show that while narcissistic recipients do not report stronger negative emotions when receiving feedback on their performance than others do, their facial muscle responses to negative feedback are amplified. The findings align with theoretical accounts on narcissistic defensiveness and demonstrate a discordance in narcissistic individuals' self‐reported and physiological reactions to social evaluation. [ABSTRACT FROM AUTHOR]