Low-constraint insert with a medial pivot design as a potential predictor of favourable outcomes in cruciate-retaining total knee arthroplasty: A propensity score-matched analysis.

PURPOSE: The influence of polyethylene insert conformity on the outcomes of cruciate-retaining (CR) total knee arthroplasty (TKA) with a medial pivot design remains uncertain. Therefore, this study aimed to evaluate the effects of polyethylene insert conformity in CR-TKA on patient-reported outcomes. METHODS: The data of 255 knees (FINE Total Knee System) from 255 patients were retrospectively analysed to compare outcomes for high- or low-constraint medial pivot inserts, as determined through historical controls, over an average follow-up period of 2.2 years (range, 2.0-5.5 years). Multivariate logistic regression analysis was used to identify predictors of achieving the patient-acceptable symptom state (PASS) for the Forgotten Joint Score-12 (FJS-12). Propensity score-matched cohorts for age, sex, body mass index, Kellgren-Lawrence grade, Charlson Comorbidity Index, knee flexion contracture, FJS-12 and follow-up duration were created for between-group comparison (n = 50 in each group). RESULTS: Low-constraint insert (p = 0.031) and age (p = 0.043) were independent predictors of achieving the PASS for the FJS-12 (>33, 153/255). After successful matching, compared to the high-constraint insert, the low-constraint insert improved patient satisfaction (p = 0.029 for pain on going up or downstairs, and p = 0.047 for the function of going upstairs) and increased the likelihood of achieving the minimal clinically important difference (p = 0.019) and PASS (p = 0.025) for the FJS-12. A significant correlation was observed between the posterior tibial slope and the FJS-12 in the low-constraint insert group (p < 0.001), indicating that a greater posterior tibial slope was associated with better functional outcomes in this group. CONCLUSIONS: Compared with high-constraint inserts, low-constraint medial pivot inserts yielded higher functional outcomes and patient satisfaction. Therefore, insert conformity may play a crucial role in CR-TKA outcomes. LEVEL OF EVIDENCE: Level III.

Measurement uncertainty for <711> Dissolution tests using Monte Carlo methods - Uncertainties arising from sampling and analytical steps.

BACKGROUND: The dissolution test is a critical quality control method in the pharmaceutical industry, primarily used to assess drug bioavailability and ensure the consistency of manufactured batches. This test simulates the release of the active ingredient in the body and verifies compliance with specifications through multiple stages (e.g., S1, S2, S3). However, measurement uncertainty can undermine the reliability of test results, potentially leading to erroneous conformity decisions. This study aims to quantify the uncertainties arising from the dissolution, sampling, and quantification steps, as well as to estimate the risk of false conformity decisions in the dissolution test results for tablets. RESULTS: A comprehensive uncertainty evaluation was conducted for the dissolution, sampling, and quantification stages. The Monte Carlo method (MCM) was applied to assess the overall measurement uncertainty, which was determined to be approximately 5.2 %. The study revealed that sampling was the predominant contributor, accounting for 92 % of the total uncertainty, compared to 7 % from quantification and 1 % from dissolution steps. An MS Excel spreadsheet was developed to calculate the total risk value and classify it as either producer or consumer risk. This tool enables the evaluation of uncertainty in both individual tested units and mean values, depending on the stage criteria (e.g., S1, S2, S3). The proposed improved criteria were tested across various scenarios where the risk of false decisions due to measurement uncertainty was considered. These tests demonstrated the effectiveness of the criteria in managing consumer risk, highlighting the critical impact of sampling uncertainty on the decision-making process. SIGNIFICANCE AND NOVELTY: This study introduces novel, improved criteria for the dissolution test that account for the risk of false decisions due to measurement uncertainty. The proposed criteria significantly enhance the reliability of drug quality assessments. The study provides a robust framework for minimizing false conformity decisions. The development of a practical MS Excel tool further supports the reliable assessment of dissolution test results, ensuring higher standards of drug safety and efficacy in pharmaceutical quality control.

Discrepancy between antibiotic pack sizes and guideline recommendations: a real-world analysis based on claims data.

PURPOSE: Antibiotics are often only available in predefined pack sizes, which may not align with guideline recommendations. This can result in leftover pills, leading to inappropriate self-medication or waste disposal, which can both foster the development of antibiotic resistance. The magnitude of inappropriate pack sizes is largely unknown. The objective of this study was to evaluate the potential non-conformity of prescribed antibiotic pack sizes. METHODS: This retrospective observational study was based on claims data from a large Swiss health insurance company. The study analysed the prescriptions of eleven different antibiotic substances recommended for the five most common indications for antibiotics in Switzerland. All prescriptions for adult outpatients issued by general practitioners in 2022 were included and extrapolated to the entire Swiss population. Potential non-conformity was defined as a mismatch between the total dosage in a pack and the total dosage recommended. RESULTS: A total of n = 947,439 extrapolated prescriptions were analysed. In 10 of 23 of all analysed substance/indication combinations none of the prescribed packs aligned with the respective guideline recommendation. Considering pack sizes in which the total prescribed dosage of a substance did not correspond to any of the total dosages recommended in at least one of the guidelines, 31.6% of prescriptions were potentially non-conform and an estimated number of 2.7 million tablets were overprescribed. CONCLUSIONS: We found a large discrepancy between prescribed pack sizes and guideline recommendations. Since inadequately prepacked antibiotics may lead to antibiotic resistance and unnecessary waste, efforts are needed to implement alternatives like exact pill dispensing.

The role of loss aversion in social conformity: psychological and neural representations.

The impact of others' choices on decision-making is influenced by individual preferences. However, the specific roles of individual preferences in social decision-making remain unclear. In this study, we examine the contributions of risk and loss preferences as well as social influence in decision-making under uncertainty using a gambling task. Our findings indicate that while both individual preferences and social influence affect decision-making in social contexts, loss aversion plays a dominant role, especially in individuals with high loss aversion. This phenomenon is accompanied by increased functional connectivity between the anterior insular cortex and the temporoparietal junction. These results highlight the critical involvement of loss aversion and the anterior insular cortex-temporoparietal junction neural pathway in social decision-making under uncertainty. Our findings provide a computational account of how individual preferences and social information collectively shape our social decision-making behaviors.

Determining Simple and Effective Cost Functions for an Efficient Volumetric-Modulated Arcs-Based Stereotactic Radiosurgery for Single Brain Metastases Using Monaco® Planning System.

Introduction Volumetric-modulated arcs (VMA) can produce dose distributions suitable for stereotactic radiosurgery (SRS) with a multi-leaf collimator (MLC) for brain metastases (BMs). The treatment planning and verification for VMA are more complicated than for dynamic conformal arcs. The longer the preparation time from image acquisition to the start of irradiation, the higher the risk of tumor growth and/or displacement. This planning study aimed to exploit the simple and effective cost function (CF) for establishing semi-automatic efficient VMA optimization for SRS of single BMs. Materials and methods The study population included 30 clinical BMs with a gross tumor volume (GTV) of 0.72-44.30 cc (median 9.81 cc) and a depth of 20-79 mm (median 41 mm). The treatment platform included a 5-mm leaf-width MLC Agility® (Elekta AB, Stockholm, Sweden) and a planning system Monaco® (Elekta AB). Among various physical and biological CFs available, three combinations consisting of just two or three physical CFs were compared. The Target Penalty CF was uniformly used for ensuring the GTV dose. Three different CF combinations were applied for reducing the surrounding tissue doses: (1) the Conformality alone with the 4-cm margin around target (MAT) that optimizes the limited voxels around the GTV (woQO); (2) the Conformality with the 4-cm MAT and the Quadratic Overdose (wQO_4 cm); and (3) the Conformality with the 8-cm MAT that optimizes the overall voxels around the GTV and the Quadratic Overdose (wQO_8 cm). The prescribed dose was uniformly assigned to each GTV D V-0.01 cc, the minimum dose of GTV minus 0.01 cc. Results Adding the Quadratic Overdose (wQO_4 cm and wQO_8 cm) significantly improved the overall dose distribution in comparison to the woQO, while no significant difference was observed between the wQO_4 cm and wQO_8 cm overall. However, for the GTVs of ≥14 cc, the GTV dose conformity and dose gradient outside the GTV boundary, including the dose attenuation margin, were significantly superior in the wQO_8 cm than wQO_4 cm. In addition, for the GTV depth of ≥41 mm, the GTV dose conformity and the dose concentric lamellarity at 2 mm outside the GTV were significantly superior in the wQO_8 cm than wQO_4 cm. Meanwhile, for the GTVs of ≥10 cc, the GTV dose was significantly more inhomogeneous in the wQO_4 cm than the wQO_8 cm. In addition, for the GTVs of <10 cc and the depth of ≤40 mm, the dose concentric lamellarity at 4 mm inside the GTV surface was significantly higher in the wQO_4 cm than the wQO_8 cm. Conclusions Applying at least three physical CFs to a GTV and the head surface contour is recommended as an effective and efficient optimization method using Monaco for VMA-based SRS of single BMs. In addition, optimizing the overall voxels around the GTV is suitable for reducing the surrounding tissue dose, especially for large and deeply located lesions. Templating the combination of the three CFs with the detailed settings allows for semi-automated and rapid treatment planning, facilitating the prompt start of irradiation after image acquisition.

Application of a customized 3D-printed osteotomy guide plate for tibial transverse transport.

Enhance the efficiency of tibial transverse transport by employing customized 3D-printed osteotomy guide plates and striving to improve precision through CT evaluation for enhanced guide design. 17 diabetic foot patients were treated with the plate for tibial transverse transport. Preoperatively, we collected DICOM data from the affected tibia's CT and designed the geometric parameters of the tibial cortical bone window. A customized 3D-printed osteotomy guide plate was then fabricated using 3D printing technology. Postoperative X-ray and CT evaluations, conducted at two and five weeks post-surgery, assessed five crucial geometric parameters of the bone window. Measurements included the distance from the upper edge of the tibial cortical bone window to the tibial plateau, the distance from the anterior edge of the tibial cortical bone window to the bone ridge, the height of the tibial cortical bone window, the center-to-center distance between the 4.0 mm diameter Schanz pin and the osteotomy Kirschner pin, and the center-to-center distance of the 4.0 mm diameter Schanz pin. These measured parameters were subsequently compared to the preoperative design parameters. The Clinical trial registration number is ChiCTR2400087174. CT measurements showed no significant differences (P > 0.05) from preoperative design parameters across the five evaluated aspects. The average osteotomy duration was 35 ± 15 min with no bone window fractures. The bone window aligned effectively with the tibial shaft, achieving complete incorporation after distraction. A 4 to 8-month postoperative follow-up confirmed full healing of the tibial surgical wound and diabetic foot wounds. Utilizing customized 3D-printed osteotomy guide plates in tibial transverse bone transport surgery enables accurate translation of preoperative virtual designs into real-time procedures, enhancing surgical efficiency and quality.

Cultural Values Influence the Developmental Trajectory of Resistance to Social Influence Over the Course of Adolescence.

The opinions of peers are among the most potent factors influencing human decision-making. Research conducted in Western societies suggests that individuals become more resistant to peer influence from late adolescence to adulthood. It is unknown whether this developmental trajectory is universal across cultures. Through two cross-national studies, we present consistent self-report and behavioral evidence for culturally distinct developmental trajectories of resistance to peer influence (RPI). Our findings from the US samples replicated prior findings that reported increasing RPI. Yet, data from the Chinese participants were better fitted using a nonlinear model, displaying a U-shaped trajectory with lowest RPI levels at around 20 years old. In contrast to the long-held belief that increasing RPI from adolescence to early adulthood is a universal developmental trait, we propose that this developmental trajectory may depend on cultural context.

A lung SBRT treatment planning technique to focus high dose on gross disease.

This study investigated a straightforward treatment planning technique for definitive stereotactic body radiation therapy (SBRT) for patients with early-stage lung cancer aimed at increasing dose to gross disease by strategically penalizing the normal tissue objective (NTO) in the EclipseTM treatment planning system. Twenty-five SBRT cases were replanned to 50 Gy in 5 fractions using static and dynamic NTO methods (50 plans total). The NTO had a start dose of 100% at the target border, end dose of 20%, fall-off rate of 0.4/mm, and a priority of 150. For the static NTO plans, a lower planning target volume (PTV) objective was placed at 52 Gy with a priority of 100. Maximum dose was not penalized. Optimization was performed without user interaction. In contrast, the planner incrementally increased the priority of the NTO on the dynamic NTO plans until 95% of the target volume was covered by the prescription dose. Further, the dynamic NTO plans used both PTV lower and upper objectives at 63-64 Gy with priorities of 50. Maximum dose was penalized to ensure that the hot spot was within ± 2% of the static NTO global maximum dose. Following optimization, all plans were normalized so that the prescription dose covered 95% of the PTV. Plans were scored based on RTOG 0813 criteria, and dose to the internal target volume (ITV) and PTV was evaluated. The Wilcoxon signed-rank test (threshold = 0.05) was used to evaluate differences between the static and dynamic NTO plans. All plans met RTOG 0813 planning guidelines. In comparison to the static NTO plans, the dynamic NTO plans exhibited statistically significant increases in PTV mean dose, ITV mean dose, and PTV-ITV mean dose. Notably, the dynamic NTO plans more effectively concentrated the high dose on gross disease at the center of the PTV. As compared to the static NTO plans, the mean dose was 4.6 Gy higher in the ITV while only 1.3 Gy higher in the PTV-ITV rind of the dynamic NTO plans. Global maximum doses were similar. There were some small yet statistically significant differences in dose conformity between plan types. Furthermore, the dynamic NTO plans demonstrated a significant reduction in total monitor units (MU). This study demonstrated an efficient optimization strategy for lung SBRT plans that concentrates the highest dose in the gross disease, which may improve local control.

Lung SBRT: Dose gradient optimization based on target size.

This study investigated optimization settings that steepen the dose gradient as a function of target size for lung stereotactic body radiation therapy (SBRT). Sixty-eight lung SBRT patients with planning target volumes (PTVs) ranging from 2-203 cc were categorized into small (<20 cc), medium (20-50 cc), and large (>50 cc) groups. VMAT plans were generated using the normal tissue objective (NTO) to penalize the dose gradient at progressively steeper NTO fall-off values (0.1, 0.2, 0.3, 0.4, 0.5 mm-1). Dose was calculated using the AcurosXB algorithm and was normalized so the prescription dose covered 95% of the PTV. Mann-Whitney, Kruskal-Wallis and ANOVA tests were used to assess for statistical differences in the Conformity Index at the 50% isodose level (CI50%), global maximum dose (Dmax), and monitor units (MU) across the various NTO settings. All plans adhered to institutional criteria and met the guidelines of the Radiation Therapy Oncology Group 0813. Steeper NTO fall-off values significantly increased Dmax and MUs across all groups (p < 0.05). CI50% significantly differed with fall-off values in small (0.3 mm-1) and medium (0.2 mm-1) targets, indicating steeper NTO fall-off values improve CI50% for small and medium targets (p < 0.05). Large targets showed no significant CI50% difference across these fall-off values. As target size increases, the importance of fall-off values in achieving an acceptable CI50% diminishes. Smaller targets benefit from steeper fall-off values despite increased Dmax and MUs. Consideration of fall-off value relative to target size is crucial to limit dose spillage outside the target.

Study on hand disinfection in inpatient geriatric care on the superiority of cold plasma aerosol versus alcohol-based disinfection methods in a parallel group design.

The introduction of fundamental hygiene protocols within the healthcare sector during the nineteenth century led to a significant reduction in mortality rates. Contemporary advancements, such as alcohol-based sanitizers, have further enhanced hand hygiene practices. However, these measures are often overlooked in nursing facilities, resulting in low staff compliance rates and increased cross-infection rates. Novel approaches, such as cold plasma hand disinfection, present promising alternatives due to their minimal skin damage and economic benefits. This study aims to compare the disinfectant efficacy of cold plasma aerosol under practical application conditions with an alcoholic hand disinfectant listed by the Association for Applied Hygiene. The microbial count on participants' hands was measured, with particular attention paid to the spontaneous occurrence of fecal indicators and the presence of potentially infectious bacteria. A t-test for independent samples was conducted to determine whether there was a significant difference between the two cohorts regarding the research question. Statistical analysis revealed that the mean log colony-forming unit (CFU) values were significantly lower in the test cohort using only the cold plasma method for hand disinfection compared to the cohort using conventional alcohol-based hand disinfection. Moreover, it was demonstrated that, unlike alcohol-based hand disinfection, cold plasma application ensures the effective elimination of Staphylococcus aureus. The findings indicate that staff utilizing plasma disinfection have an average bacterial count that is 0.65 log units lower than those who regularly use alcohol-based hand disinfection. In addition to the efficacy of cold plasma disinfection, its superiority over alcohol-based hand disinfection was also established. Beyond offering economic and logistical advantages, cold plasma disinfection provides additional health benefits as it does not induce skin damage, unlike alcohol-based hand disinfection.

Lessons learned: drive-through COVID-19 clinic testing during an adaptive epidemic response and a point-of-care test assessment of a computer-read rapid lateral flow immunoassay with fluorescence-based detection.

Background. The COVID-19 pandemic demonstrated a need for robust SARS-CoV-2 test evaluation infrastructure to underpin biosecurity and protect the population during a pandemic health emergency.Gap statement. The first generation of rapid antigen tests was less accurate than molecular methods due to their inherent sensitivity and specificity shortfalls, compounded by the consequences of self-testing. This created a need for more accurate point-of-care SARS-CoV-2 detection methods.Aim. Here we present the lessons-learned during the COVID-19 emergency response in Western Australia including the detailed set-up, evaluation and operation of rapid antigen test in a state-run drive-through sample collection service during the COVID-19 pandemic after the strict border shutdown ended.Methods. We report a conformity assessment of a novel, second-generation rapid antigen test (Virulizer) comprising a technician-operated rapid lateral flow immunoassay with fluorescence-based detection.Results. The Virulizer rapid antigen test demonstrated up to 100% sensitivity (95% CI: 61.0-100%), 91.94% specificity (95% CI: 82.5-96.5%) and 92.65% accuracy when compared to a commercial PCR assay method. Wide confidence intervals in our series reflect the limits of small sample size. Nevertheless, the Virulizer assay performance was well-suited to point-of-care screening for SARS-CoV-2 in a drive-through clinic setting.Conclusion. The adaptive evaluation process necessary under changing pandemic conditions enabled assessment of a simple sample collection and point-of-care testing process, and showed how this system could be rapidly deployed for SARS-CoV-2 testing, including to regional and remote settings.

Non-coplanar Arc-Involved Beam Arrangement With Sufficient Arc Rotations Is Suitable for Volumetric-Modulated Arc-Based Radiosurgery for Single Brain Metastasis.

Introduction In linac-based stereotactic radiosurgery (SRS) leveraging a multileaf collimator (MLC) for brain metastasis (BM), volumetric-modulated arcs (VMAs) enable the generation of a suitable dose distribution with efficient planning and delivery. However, the arc arrangement, including the number of arcs, allocation, and rotation ranges, varies substantially among devices and facilities. Some modalities allow coplanar arc(s) (CA(s)) or beam(s) alone, and some facilities only use them intentionally despite the availability of non-coplanar arcs (NCAs). The study was conducted to examine the significance of NCAs and the optimal arc rotation ranges in VMA-based SRS for a single BM. Materials and methods This was a planning study for the clinical scenario of a single BM, including 20 clinical cases with a gross tumor volume (GTV) of 0.72-44.30 cc. Three different arc arrangements were compared: 1) reciprocating double CA alone of each 360º rotation with different collimator angles of 0 and 90º, 2) one CA and two NCAs of each 120º rotation with the shortest beam path lengths to the irradiation isocenter (NCA_L), and 3) one CA of 360º rotation and two NCAs of each 180º rotation (NCA_F). The three arcs were allocated similarly to equally divide the cranial hemisphere with different collimator angles of 0, 45, and 90º. Three VMA-based SRS plans were generated for each GTV using a 5 mm leaf-width MLC with the identical optimization method that prioritized the steepness of dose gradient outside the GTV boundary without any constraints to the GTV internal dose. A prescribed dose was uniformly assigned to the GTV D V-0.01 cc, the minimum dose of GTV minus 0.01 cc. The GTV dose conformity, the steepness of dose gradients both outside and inside the GTV boundary, the degree of concentric lamellarity of the dose gradients, and the appropriateness of the dose attenuation margin outside the GTV boundary were evaluated using metrics appropriate for each. Results The arc arrangements including NCAs showed significantly steeper dose gradients both outside and inside the GTV boundary with smaller dose attenuation margins than the CAs alone, while NCAs showed no significant advantage on the GTV dose conformity. In the NCA-involved arc arrangements, the NCA_F was significantly superior to the NCA_L in terms of the GTV dose conformity, the steepness of dose gradient outside the GTV, the degree of concentric lamellarity of the dose gradients outside and inside the GTV boundary, and the appropriateness of dose attenuation margin. However, the NCA_F showed no significant advantage on the steepness of dose increase inside the GTV boundary over the NCA_L. The dose increase just inside the prescribed isodose surface to the GTV boundary was significantly steeper with the NCA_L than the NCA_F. Conclusions In VMA-based SRS for a single BM, an arc arrangement including NCAs is indispensable, and sufficient arc rotations are suitable for achieving a dose distribution that maximizes therapeutic efficacy and safety in comparison to limited ones which are appropriate for dynamic conformal arcs. Although VMA with CAs alone can provide a non-inferior GTV dose conformity to NCAs, CA(s) alone should be applied only to situations where shorter irradiation time is prioritized over efficacy and safety.

In-house validation of a visible and near infrared spectroscopy non-targeted method to support panel test of virgin olive oils.

In this study, an in-house validation of Visible and Near Infrared Spectroscopy was performed to distinguish between extra virgin olive oil (EVOO) and virgin olive oil (VOO). A total of 161 samples of olive oil of three different categories (EVOO, VOO and lampante (LOO)) were analysed by transflectance using a monochromator instrument. One-class models were initially developed using Partial Least Squares (PLS) Density Modelling to characterize EVOO and VOO category. Once the LOO samples were discriminated, linear and non-linear discriminant models were built to classify EVOO and VOO. Different data pre-treatments and variable selection algorithms were evaluated to establish the best models in terms of Correct Classification Rate (CCR). The best model, obtained after variable selection using PLS Discriminant Analysis, yielded CCR values of 82.35 % for EVOO and 66.67 % for VOO in external validation. These results confirmed that VIS + NIRS technology may be used to provide rapid, non-destructive preliminary screening of olive oil samples for categorization; suspect samples may then be analysed by official analytical methods.

Strategy and Metrological Support for Indoor Radon Measurements Using Popular Low-Cost Active Monitors with High and Low Sensitivity.

Traditionally, for indoor radon testing, predominantly passive measurements have been used, typically applying the solid-state alpha track-etch method for long-term and the charcoal method for short-term measurements. However, increasingly, affordable consumer-grade active monitors have become available in the last few years, which can generate a concentration time series of an almost arbitrary duration. Firstly, we argue that consumer-grade monitors can well be used for quality-assured indoor radon assessment and consequent reliable decisions. Secondly, we discuss the requirements of quality assurance, which actually allow for reliable decision-making. In particular, as part of a rational strategy, we discuss how to interpret measurement results from low-cost active monitors with high and low sensitivity with respect to deciding on conformity with reference levels that are the annual average concentration of indoor radon. Rigorous analysis shows that temporal variations in radon are a major component of the uncertainty in decision-making, the reliability of which is practically independent of monitor sensitivity. Manufacturers of low-cost radon monitors already provide sufficient reliability and quality of calibration for their devices, which can be used by both professional inspectors and the general public. Therefore, within the suggested measurement strategy and metrologically assured criteria, we only propose to clarify the set and values of the key metrological characteristics of radon monitors as well as to upgrade user-friendly online tools. By implementing clear metrological requirements as well as the rational measurement strategy for the reliable conformity assessment of a room (building) with radon safety requirements, we anticipate significant reductions in testing costs, increased accessibility, and enhanced quality assurance and control (QA/QC) in indoor radon measurements.

Anticonformists catalyze societal transitions and facilitate the expression of evolving preferences.

The world is grappling with emerging, urgent, large-scale problems, such as climate change, pollution, biodiversity loss, and pandemics, which demand immediate and coordinated action. Social processes like conformity and social norms can either help maintain behaviors (e.g. cooperation in groups) or drive rapid societal change (e.g. rapid rooftop solar uptake), even without comprehensive policy measures. While the role of individual heterogeneity in such processes is well studied, there is limited work on the expression of individuals' preferences and the role of anticonformists-individuals who value acting differently from others-especially in dynamic environments. We introduce anticonformists into a game-theoretical collective decision-making framework that includes a complex network of agents with heterogeneous preferences about two alternative options. We study how anticonformists' presence changes the population's ability to express evolving personal preferences. We find that anticonformists facilitate the expression of preferences, even when they diverge from prevailing norms, breaking the "spiral of silence" whereby individuals do not act on their preferences when they believe others disapprove. Centrally placed anticonformists reduce by five-fold the number of anticonformists needed for a population to express its preferences. In dynamic environments where a previously unpopular choice becomes preferred, anticonformists catalyze social tipping and reduce the "cultural lag," even beyond the role of committed minorities-that is, individuals with a commitment to a specific cause. This research highlights the role of dissenting voices in shaping collective behavior, including their potential to catalyze the adoption of new technologies as they become favorable and to enrich democracy by facilitating the expression of views.

Adolescent boys' aggressive responses to perceived threats to their gender typicality.

When adult men are made to feel gender-atypical, they often lash out with aggression, particularly when they are pressured (vs. autonomously motivated) to be gender-typical. Here, we examined the development of this phenomenon. Specifically, we provided a first experimental test of whether threatening adolescent boys' perceived gender typicality elicits aggression as a function of their pressured (vs. autonomous) motivation to be gender-typical. We also investigated whether this causal link emerges as a function of boys' chronological age versus pubertal development. Participants were a geographically diverse sample of 207 adolescent US boys (ages 10-14; 23.2% boys of color) and one of their parents. Boys played a "game" and received randomly-assigned feedback that their score was atypical versus typical of their gender. For boys in mid-to-late puberty (but not before), feedback that they are gender-atypical predicted an aggressive reaction, particularly among boys whose motivation to be gender-typical was pressured (vs. autonomous). Next, we explored which aspects of boys' social environments predicted their pressured motivation to be gender-typical. Boys' pressured motivation was positively correlated with their perceptions that their parents and peers would be "upset" if they deviated from gender norms, as well as with their parents' endorsement of so-called hegemonic beliefs about masculinity (i.e., that men should hold power over women). Parents with these beliefs resided in more conservative areas, had less formal education, and had lower incomes. Our results inform theorizing on gender identity development and lay the foundation for mitigating the harmful effects of gender typicality threat among adult men. RESEARCH HIGHLIGHTS: Similar to young adult men, adolescent boys in mid-to-late puberty (but not before) responded with aggression to perceived threats to their gender typicality. Aggression was heightened among boys whose motivation to be gender-typical was pressured (i.e., driven by social expectations) rather than autonomous. Which boys showed pressured motivation? Those whose parents endorsed hegemonic beliefs about masculinity (e.g., that men should have more power than people of other genders). Hegemonic beliefs about masculinity were strongest among parents who resided in more conservative US counties, had less formal education, and had lower incomes.

A dosimetric evaluation of intensity modulated radiotherapy and three-dimensional conformal radiotherapy for prostate cancer in Ghana.

External beam radiotherapy incorporates treatment techniques such as three-dimensional conformal radiotherapy (3DCRT), intensity-modulated radiotherapy (IMRT), image-guided radiotherapy and volumetric modulated arc therapy to deliver high-energy radiation to cancer. The use of IMRT for cancer treatment is also associated with significant costs for patients in low-middle-income countries. The purpose of this study was to compare the dosimetric properties of 3DCRT and IMRT treatment plans for the external beam irradiation of patients with prostate cancer (Pca) to ascertain the superiority of IMRT in terms of dose homogeneity, conformity and dose limitation to organs at risk (OAR) in a resource-limited setting. One hundred and sixty treatment plans for 80 patients were created using 3DCRT and IMRT on the Eclipse treatment planning system (version 13.6). Data were collected and assessed from the dose-volume histogram of each plan. The conformity and homogeneity index (HI) for each of the plans were calculated. The doses to the OAR were also recorded and evaluated. The mean HIs for the IMRT and 3DCRT treatment techniques were 0.04 ± 0.02 (range: 0.01-0.011) and 0.09 ± 0.02 (range: 0.04-0.016), respectively. The mean conformity index (CI) for IMRT and 3DCRT techniques were 1.257 ± 0.112 (range: 0.99-1.58) and 1.302 ± 0.196 (range: 1.10-2.26). IMRT had a better significant mean HI and CI compared to 3DCRT. Generally, for this study, IMRT had better organ sparing compared to 3DCRT. The mean doses for the OARs ranged from 4.3-74.6 Gy for IMRT and 3.1-75.9 Gy for the 3DCRT technique. Overall, this study demonstrates that IMRT may offer an enhanced therapeutic profile, potentially reducing toxicity to the patient and ensuring more precise dose delivery to the target volume compared to 3DCRT in PCa external beam irradiation.

Decoding the Dynamics of Cultural Change: A Cultural Evolution Approach to the Psychology of Acculturation.

PUBLIC ABSTRACT: Acculturation describes the cultural and psychological changes resulting from intercultural contact. Here, we use concepts from "cultural evolution" to better understand the processes of acculturation. Cultural evolution researchers view cultural change as an evolutionary process, allowing them to borrow tools and methods from biology. Cultural evolutionary mechanisms such as conformity (copying the numerical majority), anti-conformity (copying the numerical minority), prestige bias (copying famous individuals), payoff bias (copying successful people), and vertical cultural transmission (copying your parents) can cause people to adopt elements from other cultures and/or conserve their cultural heritage. We explore how these transmission mechanisms might create distinct acculturation strategies, shaping cultural change and diversity over the long-term. This theoretical integration can pave the way for a more sophisticated understanding of the pervasive cultural shifts occurring in many ethnically diverse societies, notably by identifying conditions that empower minority-group members, often marginalized, to significantly influence the majority group and society.

Conformity behavior in crises: evidence from the COVID-19 epidemic in China.

Once a mass health crisis breaks out, it causes concern among whole societies. Thus, understanding the individual's behavior in response to such events is key in government crisis management. From the perspective of social influence theory, this study adopts the empirical research method to collect data information in February 2020 through online survey, with a view to comprehensively describe the individuals'conformity behavior during the COVID-19 outbreak in China. The individual's conformity behavior and new influencing factors were identified. The results revealed that affective risk perception, cognitive risk perception, and individual risk knowledge had a positive significant impact on normative influence. Affective risk perception and individual risk knowledge had a positive significant on informative influence. Cognitive risk perception did not significantly impact informative influence. Informative influence and normative influence had a positive effect on conformity behavior. These results have significant implications for the management behavior of the government.

Trend Conformity Behavior of Luxury Fashion Products for Chinese Consumers in the Social Media Age: Drivers and Underlying Mechanisms.

When a bandwagon consumption trend of luxury fashion products appears, potential consumers tend to conform to the trend. The conformity behavior is enhanced by social media because it makes bandwagon trends more visible. However, no research has explored the drivers of fashion trend conformity in the social media age and the underlying mechanisms. Our empirical research demonstrates that fashion trend conformity is a socially directed type of behavior driven by trend perception and reference group pressure, which represent the informational and normative social influence stimuli, respectively. In addition to the direct impact, we also examine the mediating roles of demand amplification and the urge to buy impulsively (UBI). Demand amplification and UBI, respectively, reflect the rational cognitive reaction and irrational emotional reaction to stimuli of fashion bandwagon consumption. However, our results show that only the cognitive reaction path works, but the emotional reaction path does not. Put simply, trend conformity behavior is largely the result of consumers' rational reactions rather than irrational reactions to the social influence stimuli of bandwagon consumption. Our study contributes to the research on luxury fashion consumption by introducing three new concepts, i.e., fashion trend conformity, trend perception, and demand amplification, to describe and theorize the characteristics of consumer behavioral patterns for luxury fashion products and new drivers and novel underlying mechanisms of consumer behaviors in the social media age. Our findings offer practical insights for retailers and manufacturers to promote fashion trend conformity behavior.