Variability across time in implicit weight-related bias: Random noise or meaningful fluctuations?

Social psychologists have struggled with the vexing problem of variability over time in implicit bias. While many treat such variability as unexplainable error, we posit that some temporal variability, whether within persons or across society at large, reflects meaningful and predictable fluctuation based on shifts in the social-cultural context. We first examined fluctuations at the group-level in a Project Implicit data set of female participants who completed the Weight Implicit Association Test between 2004 and 2018 (N = 259,613). Extending our prior work showing that mass media celebrity fat-shaming increased women's implicit antifat bias, we show that celebrity body positivity events reduced such bias (Study 1a). We then focused on a specific form of body positivity-that is, celebrity "push-back" in response to fat-shaming. Whereas fat-shaming without antibias push-back was associated with spikes in negative weight attitudes, fat-shaming with push-back showed no change in such bias (Study 1b). Critically, however, closer analysis revealed that this apparent stability was due to the canceling out of opposing negative (fat-shaming) and subsequent positive (body positivity) influences-an effect that was obscured when the window of observation was expanded. Finally, in Study 2, we examined parallel effects at the individual level in a daily diary study. Consistent with the group-level, between-subjects data, women's intraindividual fluctuations in implicit attitudes were reliably predicted based on prior-day exposure to fat-shaming and/or body positivity influences. Taken together, our work highlights how both group- and individual-level variability across time can be meaningfully explained rather than treated as unexplainable or left as unexplained. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Hip and Trunk Muscle Activity and Mechanics During Walking With and Without Unilateral Weight.

Pelvic drop is caused by decreased hip abductor muscle activity and is associated with lower-extremity injury. Hip abductor strengthening exercises are well established; however, no standard method exists to increase hip abductor activity during functional activities. The purpose of this research was to study the effects of walking with a unilateral weight. A total of 26 healthy adults walked on an instrumented treadmill with and without handheld weight (15%-20% body weight). Muscle activity, kinematic, and kinetic data were collected using surface electromyography, motion capture, and force plates, respectively. Average hip and trunk muscle activity, hip, pelvic, and trunk angles, and peak internal hip moments during stance were compared for each side (contralateral/ipsilateral to the weight) between conditions (unweighted/weighted) using a generalized linear model with generalized estimating equation correction. Interactions between condition and side were observed for muscle activity, frontal plane pelvic and trunk angles, and frontal plane hip moments (P ≤ .003). Compared with the unweighted condition, the weighted condition had higher hip abductor activity contralateral to the weight (P < .001), while no change was found ipsilateral to the weight (P ≥ .790). Similar changes were found for kinematic and kinetic variables. Walking with a unilateral weight may be a therapeutic option to increase functional hip abductor activity.

Visuospatial perspective shifting and relational self-association in dispositional shame and guilt.

Although dispositional shame and guilt have been distinguished by perceptions of the self and behavioral responses, the underlying information processing patterns remain unclear. We hypothesized that an ability to contemplate alternatives to perceptions of the current environment, i.e., flexibility in perspective shifting, may be essential to both dispositions. Dispositional shame may additionally relate to negative relational knowledge that involves a self-representation of being rejected. One hundred and six community participants rated the two dispositions, and had their flexibility in perspective shifting and internalized self-association with rejection assessed. Regression analysis indicated that a lower cost of perspective shifting was observed with dispositional guilt and shame. Yet, unlike a direct association with perspective shifting for dispositional guilt, it was an interaction between perspective shifting and negative relational knowledge that accounted for dispositional shame. The association of dispositional shame with perspective shifting was contingent upon the tendency to pair the self with rejection.

Late stage diagnosis of mucinous adenocarcinoma of the appendix: a case report of an unusual tumor with a rare presentation.

BACKGROUND: The incidence of mucinous appendiceal adenocarcinomas (MAA) has increased over the past three decades. Advanced stage tumor diagnosis is likely attributable to non-specific findings. Here we describe advanced stage appendiceal MAA presenting as inguinal ulcers, scrotal abscesses, and other nonspecific symptoms. To our knowledge, this is the first report of MAA presenting as inguinal pain with inflamed phlegmonous tissue and scrotal abscess. CASE PRESENTATION: A 67-year-old male presented to a rural facility complaining of weight-loss, fatigue, hematuria, dysuria, painful right inguinal ulceration, and right scrotal abscess drainage. Computed tomography of the abdomen and pelvis revealed a distended appendix (> 1.3 cm) and a fistula between the appendix, urinary bladder, right scrotum, and right groin. Laparoscopic appendectomy was performed and diagnosed as MAA. After a right hemicolectomy, the MAA was staged as pT3b pN0 M0 G2. CONCLUSION: This case highlights a unique presentation of late stage appendiceal MAA. Due to the increased incidence of appendiceal MAAs, reports of unique clinical features are needed to facilitate early diagnosis and intervention, especially in rural settings with limited access to specialists.

The effects of suppressing the biological stress systems on social threat-assessment following acute stress.

RATIONALE: Stress is associated with increased sensitivity to threat. Previous investigations examining how stress affects threat processing have largely focused on biomarker responses associated with either the sympathetic-nervous-system (SNS) or the hypothalamus-pituitary-adrenal (HPA) axis. OBJECTIVES: We pharmacologically suppressed activations of SNS, HPA, or both, prior to stress and investigated how each stress system modulates social threat assessment. METHODS: One hundred sixty-one healthy men and women were randomized in a between-subject design, to one of four pharmacological or placebo conditions: dexamethasone-placebo, placebo-propranolol, dexamethasone-propranolol, or placebo-placebo. Participants provided threat assessments for angry and neutral human faces on a baseline day, and immediately after stress induction on a testing day. RESULTS: With both systems responding normally to stress (placebo-placebo), threat assessment was higher for neutral faces compared with angry. Compared with placebo, SNS suppression resulted in increased threat assessment for angry faces. HPA suppression resulted in decreased threat assessment for neutral and angry faces. When both systems were suppressed, there was an increase in threat assessment for angry faces, and no difference from placebo for neutral. CONCLUSION: Our findings demonstrated that when intact, the biological stress systems adaptively support organisms during stress by focusing attention towards specific stimuli that are relevant to the threat. Dysregulations of the stress systems result in important system specific consequences on threat evaluation, such that suppression of either stress system alone resulted in reduced threat assessment for contextually relevant threatening stimuli, whereas when both systems were suppressed, individuals appear indiscriminately attentive to all potential threats in the environment, resulting in increased threat processing of both contextually relevant and irrelevant stimuli. Given that stress-related psychopathologies have been associated with dysregulations of the stress systems and biased responses to social threat, a systematic understanding of the mechanisms that underlie how stress systems modulate social threat assessment is needed, and can provide important insights into the cognitive processes that are involved in the development and maintenance of stress-related psychopathologies.

Systematic manipulations of the biological stress systems result in sex-specific compensatory stress responses and negative mood outcomes.

Women are twice as likely as men to be diagnosed with anxiety and mood disorders. One potential underlying mechanism is sex differences in physiological and psychological responses to stress; however, no studies to date have investigated this proposed mechanism experimentally. In a double-blind, placebo-controlled design, pharmacological challenges were administered to individually suppress the hypothalamic-pituitary-adrenal (HPA) axis, or the sympathetic nervous system (SNS) prior to stress exposure, to investigate sex differences in the resulting cross talk among the physiological and psychological stress responses. Sex-specific compensatory patterns and psychological effects emerged when the stress systems were manipulated. Men demonstrated heightened SNS reactivity to stress when the HPA axis was suppressed, and greater HPA reactivity after SNS suppression. This ability to react appropriately to the stressor, even with one system, did not lead to significant negative mood effects. In women, higher baseline activation (but dampened reactivity to stress) of SNS or HPA was observed when the other system was suppressed. This was coupled with worsened mood in response to stress when either stress system was compromised. Our results indicate that men and women may be differentially sensitive to fluctuations of their stress systems. This might be a potential link that underlies the sexual dimorphism in vulnerability for psychopathology.

Insecurity about getting old: age-contingent self-worth, attentional bias, and well-being.

Objectives: Older adulthood has often been recognized as a time of increased well-being and positive cognitive biases. However, older adults can also experience many social and identity challenges. We sought to investigate which older adults might be most vulnerable to these difficulties. We propose that to the extent an older adult has age-related contingent self-esteem they will be at risk for lower well-being and negative attentional biases.Methods: Across three studies, we measured older adults' self-reported aging self-worth contingencies, as well as various measures of well-being including subjective stress. We then had participants complete a cued-dot probe task, where each trial either began with an aging threat or not.Results: In an initial pilot study, we found that older adults reporting specific cognitive decline contingencies held an attentional bias toward rejection, primarily when cued with the word senile. In Study 1, we found general aging contingencies to be associated with lower well-being and a rejection bias when cued with old. In Study 2, we found that a stronger rejection bias, particularly when cued with old, was associated with greater stress.Conclusions: These findings demonstrate that older adults who are insecure about aging may have lower well-being and negatively biased social cognitive patterns. Negatively biased attentional patterns may play a key role in maintaining feelings of insecurity. Importantly, our research sheds light on those older adults who may not experience a positivity effect.

Shaping the Body Politic: Mass Media Fat-Shaming Affects Implicit Anti-Fat Attitudes.

The human psyche is profoundly shaped by its cultural milieu; however, few studies have examined the dynamics of cultural influence in everyday life, especially when it comes to shaping people's automatic, implicit attitudes. In this quasi-experimental field study, we investigated the effect of transient, but salient, cultural messages-the pop-cultural phenomenon of celebrity "fat-shaming"-on implicit anti-fat attitudes in the population. Adopting the "copycat suicide" methodology, we identified 20 fat-shaming events in the media; next, we obtained data from Project Implicit of participants who had completed the Weight Implicit Association Test from 2004 to 2015. As predicted, fat-shaming led to a spike in women's (N=93,239) implicit anti-fat attitudes, with events of greater notoriety producing greater spikes. We also observed a general increase in implicit anti-fat attitudes over time. Although these passing comments may appear harmless, we show that feedback at the cultural level can be registered by the "body politic."

Psychological, endocrine, and neural correlates of attentional bias in subclinical depression.

BACKGROUND: Our knowledge with respect to psychological, endocrine, and neural correlates of attentional bias in individuals with high vulnerability to developing depression - the subclinically depressed, still remains limited. DESIGN: The study used a 2 × 2 mixed design. METHODS: Attentional bias toward happy and sad faces in healthy (N = 26) and subclinically depressed individuals (N = 22) was assessed via a neuroimaging dot-probe attention task. Participants also completed trait and state psychological measures and provided saliva samples for cortisol analysis. RESULTS: The subclinical group showed attentional bias toward happy faces; past use of problem-focused coping strategies when dealing with a personally relevant stressor as well as state levels of anxiety, together, contributed to this bias. In the control group, the happy attentional bias was positively correlated with activity in the right caudate. In the subclinical group, the bias was negatively associated with the left fusiform gyrus and positively with the left inferior parietal lobule and bilateral putamen. We observed group differences in association between cortisol levels during the task and neural activity during happy attentional bias processing within the key regions involved in attention. CONCLUSIONS: The attentional bias toward happy faces may reflect an active coping attempt by the subclinical participants.

The primary care physician/nephrologist partnership in treating chronic kidney disease.

Chronic kidney disease (CKD) continues to be an ever-increasing health problem in the United States and elsewhere. Diabetes mellitus and hypertension remain the primary causes, and much of this is related to increased rates of obesity. Studies have demonstrated that early referral to a nephrologist can be life-saving and can also markedly improve quality of life. Besides recommending treatments for CKD, early referral can assist in medication management and in minimizing exposure to potential nephrotoxins. In patients who progress to end-stage renal disease, having an established patient-PCP-nephrologist relationship can ease the transition to renal replacement therapy or transplantation.

The "Rod and Fran Test": relationship priming influences cognitive-perceptual performance.

We theorized that interpersonal relationships can provide structures for experience. In particular, we tested whether primes of same-sex versus mixed-sex relationships could foster cognitive-perceptual processing styles known to be associated with independence versus interdependence respectively. Seventy-two participants visualized either a same-sex or other-sex relationship partner and then performed two measures of cognitive-perceptual style. On a computerized Rod and Frame Test, individuals were more field-dependent after visualizing a mixed-sex versus same-sex relationship partner. On a measure involving perceptions of group behavior, participants demonstrated more holistic/contextually based perception after being primed with a female versus male relationship partner. These findings support the hypothesis that activated cognitive structures representing interpersonal relationships can shape individuals' cognitive-perceptual performance.

Facial expressions depicting compassionate and critical emotions: the development and validation of a new emotional face stimulus set.

Attachment with altruistic others requires the ability to appropriately process affiliative and kind facial cues. Yet there is no stimulus set available to investigate such processes. Here, we developed a stimulus set depicting compassionate and critical facial expressions, and validated its effectiveness using well-established visual-probe methodology. In Study 1, 62 participants rated photographs of actors displaying compassionate/kind and critical faces on strength of emotion type. This produced a new stimulus set based on N = 31 actors, whose facial expressions were reliably distinguished as compassionate, critical and neutral. In Study 2, 70 participants completed a visual-probe task measuring attentional orientation to critical and compassionate/kind faces. This revealed that participants lower in self-criticism demonstrated enhanced attention to compassionate/kind faces whereas those higher in self-criticism showed no bias. To sum, the new stimulus set produced interpretable findings using visual-probe methodology and is the first to include higher order, complex positive affect displays.

Enteral arginine partially ameliorates parenteral nutrition-induced small intestinal atrophy and stimulates hepatic protein synthesis in neonatal piglets.

BACKGROUND: Arginine is an indispensable amino acid in neonates; de novo synthesis of arginine occurs in the small intestine (SI) but is reduced during parenteral nutrition (PN), limiting the arginine available to the mucosa. We assessed the effects of route of intake and dietary concentration of arginine on protein synthesis, superior mesenteric artery (SMA) blood flow, and SI morphology. METHODS: Piglets (n = 18, 14-17 days old) were given complete PN for 3 days to induce SI atrophy, then switched to 1 of 3 treatments: arginine-free PN plus an intragastric (IG) infusion of high arginine (1.6 g · kg(-1)· d(-1), IG-H Arg) or low arginine (0.6 g · kg(-1)· d(-1), IG-L Arg) or complete high-arginine PN (1.6 g · kg(-1)· d(-1), IV-H Arg). RESULTS: Enteral arginine, irrespective of amount provided, stimulated hepatic protein synthesis compared with intravenous delivery of arginine (P = .01). SMA blood flow declined for all groups following the initiation of PN. After 48 hours on the test diets, all groups reached low constant levels, but the IV-H group was significantly higher than both IG groups (P < .05). Despite greater blood flow, the SI morphological characteristics in IV-H Arg pigs were not significantly improved over the other groups. IV-H Arg pigs had higher plasma concentrations of indispensable amino acids (tyrosine, isoleucine, and valine) compared with IG-H Arg, despite identical amino acid intakes. CONCLUSIONS: Intravenous delivery of arginine sustained the best SMA blood flow, whereas even a moderate amount of enteral arginine stimulated liver protein synthesis and maintained SI growth, independent of blood flow.

Evaluating knee replacement mechanics during ADL with PID-controlled dynamic finite element analysis.

Validated computational knee simulations are valuable tools for design phase development of knee replacement devices. Recently, a dynamic finite element (FE) model of the Kansas knee simulator was kinematically validated during gait and deep flexion cycles. In order to operate the computational simulator in the same manner as the experiment, a proportional-integral-derivative (PID) controller was interfaced with the FE model to control the quadriceps actuator excursion and produce a target flexion profile regardless of implant geometry or alignment conditions. The controller was also expanded to operate multiple actuators simultaneously in order to produce in vivo loading conditions at the joint during dynamic activities. Subsequently, the fidelity of the computational model was improved through additional muscle representation and inclusion of relative hip-ankle anterior-posterior (A-P) motion. The PID-controlled model was able to successfully recreate in vivo loading conditions (flexion angle, compressive joint load, medial-lateral load distribution or varus-valgus torque, internal-external torque, A-P force) for deep knee bend, chair rise, stance-phase gait and step-down activities.

Identifying alignment parameters affecting implanted patellofemoral mechanics.

Complications of the patellofemoral (PF) joint remain a common cause for revision of total knee replacements. PF complications, such as patellar maltracking, subluxation, and implant failure, have been linked to femoral and patellar component alignment. In this study, a dynamic finite element model of an implanted PF joint was applied in conjunction with a probabilistic simulation to establish relationships between alignment parameters and PF kinematics, contact mechanics, and internal stresses. Both traditional sensitivity analysis and a coupled probabilistic and principal component analysis approach were applied to characterize relationships between implant alignment and resulting joint mechanics. Critical alignment parameters, and combinations of parameters, affecting PF mechanics were identified for three patellar designs (dome, modified dome, and anatomic). Femoral internal-external (I-E) alignment was identified as a critical alignment factor for all component designs, influencing medial-lateral contact force and anterior-posterior translation. The anatomic design was sensitive to patellar flexion-extension (F-E) alignment, while the dome, as expected, was less influenced by rotational alignment, and more by translational position. The modified dome was sensitive to a combination of superior-inferior, F-E, and I-E alignments. Understanding the relationships and design-specific dependencies between alignment parameters can aid preoperative planning, and help focus instrumentation design on those alignment parameters of primary concern.

Proline supplementation to parenteral nutrition results in greater rates of protein synthesis in the muscle, skin, and small intestine in neonatal Yucatan miniature piglets.

Proline and arginine are each indispensable during parenteral feeding due to limited interconversion by an atrophied gut. Commercial amino acid parenteral products designed for neonates contain proline concentrations that differ by almost 4-fold. To assess the adequacy of the lowest concentration of proline provided in commercial total parenteral nutrition (TPN) products, we compared rates of tissue-specific protein synthesis and nitrogen balance in neonatal piglets provided TPN at 2 different proline concentrations. Yucatan miniature piglets (9-11 d old, n = 12) were randomized to complete isonitrogenous TPN diets with low proline (LP; L-proline as 3% of amino acids) or proline supplemented (PS; 9%). After 7 d of receiving TPN, rates of protein synthesis in liver, gastrocnemius muscle, jejunal mucosa, and skin were determined by the flooding dose technique and tissue free amino acids were measured. Nitrogen balance was assessed during the last 3 d. The LP TPN resulted in lower free proline concentrations in plasma, muscle, and skin (P < 0.05) and lower rates of protein synthesis in the jejunum (by 25%; P = 0.02), muscle (by 45%; P = 0.015), and skin (by 60%; P = 0.01); there was no difference in liver. Nitrogen retention was 20% lower in the LP group (P = 0.01). In conclusion, muscle and skin protein synthesis was profoundly sensitive to parenteral proline supply and the reduced protein synthesis in the intestine could affect intestinal integrity. Low-proline TPN solutions that are currently in wide use in neonatal care may result in impaired tissue growth.

Control-matched computational evaluation of tendo-femoral contact in patients with posterior-stabilized total knee arthroplasty.

Painful patellar crepitus is a potential complication in up to 14% of patients following posterior-stabilized (PS) total knee arthroplasty (TKA). A recent clinical study identified influential patient and surgical variables by comparing a group of crepitus patients with controls matched for age, sex, and body mass index. The purpose of our study was to evaluate effects of variables identified as significant in the clinical study, including patellar ligament length, femoral component flexion, patellar button size, and position of the joint line, on contact between the quadriceps tendon and the PS femoral component. A previously verified finite element model was utilized to estimate tendo-femoral contact during deep flexion activity. Using discrete perturbations, the computational model confirmed the clinical findings in that an increased patellar ligament length, flexed femoral component, lowered joint line, and larger patellar component all reduced potentially deleterious contact near the intercondylar notch. With the selected level of anatomic and component alignment perturbations, the most influential factor affecting tendo-femoral contact was patellar ligament length. Three crepitus patients with matched controls were subsequently modeled, and contact with the anterior border of the notch was present in each crepitus patient, but none of the controls. Alternative surgical alignments for these patients were evaluated to improve the potential long-term outcomes. By characterizing conditions that may lead to painful crepitus, the modeling approach supports clinicians by identifying pre-surgical indicators and important alignment parameters to control intraoperatively.

Dynamic finite element knee simulation for evaluation of knee replacement mechanics.

In vitro pre-clinical testing of total knee replacement (TKR) devices is a necessary step in the evaluation of new implant designs. Whole joint knee simulators, like the Kansas knee simulator (KKS), provide a controlled and repeatable loading environment for comparative evaluation of component designs or surgical alignment under dynamic conditions. Experimental testing, however, is time and cost prohibitive for design-phase evaluation of tens or hundreds of design variations. Experimentally-verified computational models provide an efficient platform for analysis of multiple components, sizes, and alignment conditions. The purpose of the current study was to develop and verify a computational model of a dynamic, whole joint knee simulator. Experimental internal-external and valgus-varus laxity tests, followed by dynamic deep knee bend and gait simulations in the KKS were performed on three cadaveric specimens. Specimen-specific finite element (FE) models of posterior-stabilized TKR were created from magnetic resonance images and CAD geometry. The laxity data was used to optimize mechanical properties of tibiofemoral soft-tissue structures on a specimen-specific basis. Each specimen was subsequently analyzed in a computational model of the experimental KKS, simulating both dynamic activities. The computational model represented all joints and actuators in the experimental setup, including a proportional-integral-derivative (PID) controller to drive quadriceps actuation. The computational model was verified against six degree-of-freedom patellofemoral (PF) and tibiofemoral (TF) kinematics and actuator loading during both deep knee bend and gait activities, with good agreement in trends and magnitudes between model predictions and experimental kinematics; differences were less than 1.8 mm and 2.2° for PF and TF translations and rotations. The whole joint FE simulator described in this study can be applied to investigate a wide range of clinical and research questions.

Assessing cardiovascular risk factors and selecting agents to successfully treat patients with type 2 diabetes mellitus.

Type 2 diabetes mellitus (T2DM), obesity, and cardiovascular disease (CVD) share a common pathogenic mechanism. The prevalence of each of these conditions is increasing at an alarming rate. Despite the availability of several treatment options for patients with T2DM and the use of intensive regimens combining several antidiabetic drugs, less than half of all patients reach a target glycosylated hemoglobin level of less than 7%. Given the rapid increase in the number of patients with T2DM and obesity, as well as the CVD morbidity and mortality associated with this burden, efforts must be made to change the course of disease. The author reviews clinical trial data on the effect of glucose control on CVD risk, the selection and timing of antihyperglycemic agents, the management of associated CVD risk factors, and strategies to improve patient adherence and acceptance-with the goal of assisting physicians in selecting appropriate management strategies for their patients with T2DM.