Fairness-Aware Ranking in Search & Recommendation Systems with Application to LinkedIn Talent Search

We present a framework for quantifying and mitigating algorithmic bias in mechanisms designed for ranking individuals, typically used as part of web-scale search and recommendation systems. We first propose complementary measures to quantify bias with respect to protected attributes such as gender and age. We then present algorithms for computing fairness-aware re-ranking of results. For a given search or recommendation task, our algorithms seek to achieve a desired distribution of top ranked results with respect to one or more protected attributes. We show that such a framework can be tailored to achieve fairness criteria such as equality of opportunity and demographic parity depending on the choice of the desired distribution. We evaluate the proposed algorithms via extensive simulations over different parameter choices, and study the effect of fairness-aware ranking on both bias and utility measures. We finally present the online A/B testing results from applying our framework towards representative ranking in LinkedIn Talent Search, and discuss the lessons learned in practice. Our approach resulted in tremendous improvement in the fairness metrics (nearly three fold increase in the number of search queries with representative results) without affecting the business metrics, which paved the way for deployment to 100% of LinkedIn Recruiter users worldwide. Ours is the first large-scale deployed framework for ensuring fairness in the hiring domain, with the potential positive impact for more than 630M LinkedIn members.Comment: This paper has been accepted for publication at ACM KDD 201

Image effects in transport at metal-molecule interfaces

We present a method for incorporating image-charge effects into the description of charge transport through molecular devices. A simple model allows us to calculate the adjustment of the transport levels, due to the polarization of the electrodes as charge is added to and removed from the molecule. For this, we use the charge distributions of the molecule between two metal electrodes in several charge states, rather than in gas phase, as obtained from a density-functional theory-based transport code. This enables us to efficiently model level shifts and gap renormalization caused by image-charge effects, which are essential for understanding molecular transport experiments. We apply the method to benzene di-amine molecules and compare our results with the standard approach based on gas phase charges. Finally, we give a detailed account of the application of our approach to porphyrin-derivative devices recently studied experimentally by Perrin et al. [Nat. Nanotechnol. 8, 282 (2013)], which demonstrates the importance of accounting for image-charge effects when modeling transport through molecular junctions

Patrones estacionales de fotoaclimatación en el alga intermareal, Cystoseira tamariscifolia (Ochrophyta)

Cystoseira tamariscifolia thalli collected from rocky shores and rockpools in winter and summer in Southern Spain were incubated for 7 days in UV transparent cylindrical vessels under outdoor conditions. Photosynthetic activity estimated as in vivo chlorophyll α fluorescence of photosystem II, photosynthetic pigments, antioxidant activity (DPPH assay), phenolic compounds and total internal C and N contents were determined after short-term (3 d) and mid-term (7 d) periods. Maximum quantum yield of PSII (Fv/Fm) was significantly higher in field-collected algae and after 7 d incubation in winter than in summer. In rocky shores and rockpools thalli, maximum electron transport rate (ETRmax) and photosynthetic efficiency (αETR) were much higher in summer than in winter. ETR of outdoor-grown thalli (in situ ETR) showed a daily pattern, with a decrease at noon in both winter and summer (3rd and 7th days). We found much higher antioxidant activity in thalli collected in summer than in winter. However, the concentration of internal UV screen substances (polyphenols) was higher in winter than in summer, whereas the release of phenolic compounds was lower. The highest capacity of acclimation in C. tamariscifolia found in summer and RS with emersion periods was explained by the highest dynamic photoinhibition, energy dissipation (non-photochemical quenching) and antioxidant activity (EC50).Talos de Cystoseira tamariscifolia recolectados en pozas y plataformas rocosas intermareales (Sur de España) en invierno y en verano se incubaron bajo radiación solar durante 7 días en recipientes cilíndricos de metacrilato transparentes a la radiación UV. Se estimó la actividad fotosintética a través de la fluorescencia de la clorofila α asociada al fotosistema II, el contenido de pigmentos fotosintéticos y compuestos fenólicos, actividad antioxidante y el contenido total en C y N internos tras 3 y 7 días de incubación. Los valores iniciales del rendimiento cuántico máximo (Fv/Fm) fueron significativamente mayores en algas recolectadas en invierno que en verano mientras que la tasa de transporte electrónico máximo (ETRmax) y la eficiencia fotosintética fueron mayores en verano que en invierno en ambas zonas. Por otra parte, la tasa de transporte electrónico determinada bajo radiación solar presentó un patrón diario, con una disminución a mediodía, tanto en invierno como en los períodos de verano. La actividad antioxidante fue mayor en algas recogidas en verano; sin embargo, la concentración interna de compuestos fenólicos fue mayor en invierno que en verano, mientras que en la tasa de excreción se observó lo contrario. La alta capacidad de aclimatación en C. tamariscifolia en algas sometidas a emersión en las plataformas rocosas en verano se explica por su alta fotoinhibición dinámica, su capacidad de disipación de energía (amortiguamiento no fotoquímico, NPQ) y su actividad antioxidante (EC50)

Socio-demographic variation in adherence to the World Cancer Research Fund (WCRF)/American Institute for Cancer Research (AICR) Cancer Prevention Recommendations within the UK Biobank prospective cohort study

\ua9 The Author(s) 2023. Published by Oxford University Press on behalf of Faculty of Public Health. Background: The 2018 (WCRF)/American Institute for Cancer Research (AICR) Cancer Prevention Recommendations are evidence-based lifestyle recommendations which aim to reduce the risk of cancer worldwide. Sociodemographic factors modulate lifestyle behaviours, and both cancer incidence and survival are socio-economically patterned. We investigated adherence to these recommendations and examined patterns of adherence across sociodemographic subgroups in the UK Biobank cohort. Methods: We included 158 415 UK Biobank participants (mean age 56 years, 53% female). Total adherence scores were derived from dietary, physical activity and anthropometric data using the 2018 WCRF/AICR standardized scoring system. One-Way analysis of variance (ANOVA) was used to test for differences in total scores and in values for individual score components according to sociodemographic factors and Pearson’s X2 test to investigate associations between sociodemographic factors according to tertiles of adherence score. Results Mean total adherence score was 3.85 points (SD 1.05, range 0–7 points). Higher total scores were observed in females, and older (>57 years), Chinese or South Asian, and more educated participants. We found significant variations in adherence to individual recommendations by sociodemographic factors including education, Townsend deprivation index and ethnicity. Conclusions: Identifying and understanding lifestyle and dietary patterns according to sociodemographic factors could help to guide public health strategies for the prevention of cancers and other non-communicable diseases

Abbreviated Score to Assess Adherence to the 2018 WCRF/AICR Cancer Prevention Recommendations and Risk of Cancer in the UK Biobank

\ua92023 The Authors; Published by the American Association for Cancer Research. BACKGROUND: The World Cancer Research Fund (WCRF)/American Institute for Cancer Research (AICR) Cancer Prevention Recommendations are lifestyle-based guidelines which aim to reduce cancer risk. This study investigated, in the UK Biobank, associations between an abbreviated score to assess adherence to these Recommendations and the risk of all cancers combined and of 14 cancers for which there is strong evidence for links with diet, adiposity, and physical activity. METHODS: We used data from 288,802 UK Biobank participants (mean age 56.2 years), cancer-free at baseline. An abbreviated version of the 2018 WCRF/AICR Score was calculated to assess adherence to five Recommendations on (i) body weight, (ii) physical activity, (iii) fruits, vegetables, and dietary fiber, (iv) red and processed meat, and (v) alcohol. Multivariable Cox proportional hazards models were used to analyze associations between the abbreviated score (range, 0-5 points) and cancer incidence, adjusting for confounders. RESULTS: During a median follow-up of 8.2 years (interquartile range, 7.4-8.9), 23,448 participants were diagnosed with cancer. The abbreviated score was inversely associated with risk of cancer overall [HR: 0.93; 95% confidence interval (CI): 0.92-0.95 per 1-point increment], and breast (HR: 0.90; 95% CI: 0.87-0.94), colorectal (HR: 0.86; 95% CI: 0.83-0.90), lung (HR: 0.89; 95% CI: 0.84-0.94), kidney (HR: 0.83; 95% CI: 0.76-0.90), pancreatic (HR: 0.86; 95% CI: 0.79-0.94), uterine (HR: 0.79; 95% CI: 0.73-0.86), esophageal (HR: 0.82; 95% CI: 0.75-0.90), stomach (HR: 0.89; 95% CI: 0.79-0.99), and liver (HR: 0.80; 95% CI: 0.72-0.90) cancers. CONCLUSIONS: Greater adherence to the Cancer Prevention Recommendations, assessed using an abbreviated score, was associated with reduced risk of all cancers combined and of nine site-specific cancers. IMPACT: Our findings support compliance to these Recommendations for cancer prevention

Tribocorrosion of commercially pure titanium in oral simulating environments

According to several studies, commercially pure (cp) titanium presents the required properties for dental applications such as mechanical resistance, low density, corrosion resistance and biocompatibility [1-3]. Also, it is widely accepted that the surface properties of the metallic material will play an essential role in the interaction between implanted materials and tissue. Whatever Ti is used in crowns or implants, a relative displacement between the implant and the adjacent material (gum, bone, porcelain…) might occur, always in the presence of an environment constituted by inorganic and organic species. Therefore, a tribocorrosion system may be formed, and the synergistic effect of wear and corrosion may lead to accelerated failure of the system. Nevertheless, few studies have focused on the tribocorrosion behavior of titanium in oral simulating environments, considering the presence of fluoride solutions and/or bacterial biofilms [4-8]. The aim of this work was to study the effect of sliding wear of cp titanium in the presence of artificial saliva containing different amounts of fluoride. Also, the behavior of the tribocorrosion system when a biofilm is present at the surface of the metallic materials was evaluated. Samples of grade 2 Ti were prepared by grinding using SiC sandpapers till 1200 mesh. Tribocorrosion tests were accomplished in Fusayama’s artificial saliva (AS) containing two different fluoride concentrations: 30 and 227 ppmF-. Open-circuit potential (OCP) was monitored during the entire experiment and electrochemical impedance spectroscopy tests (EIS) were carried out at 50 mV above corrosion potential (Ecorr) at frequencies from 100 KHz to 15.8 mHz, before and after sliding. The sliding tests were carried out using an alumina sphere as counterbody under a normal load of 3 N, an amplitude of 2 mm for 20 min. Results were statistically analyzed at significance level of p < 0.05. Samples were inspected by SEM-EDS and AFM. As shown in fig. 1, the addition of 227 ppmF- to the AS resulted in a higher Ecorr during sliding. However, in the same solution, Ti presents a significantly higher passive current density in the absence of mechanical action. During sliding, third-body particles were produced, and chemical analysis of the solution revealed a significant release of Ti ions. The influence of the presence of bacterial cultures of S.mutans on the corrosion and tribocorrosion behavior of titanium is also discussed.Fundação para a Ciência e a Tecnologia (FCT)Programa Alban - Bolsas de Alto Nível da União Europeia para a América LatinaFlemish Science Foundation.Scientific Research Community on Surface Modification of Material

Adherence to the 2018 World Cancer Research Fund (WCRF)/American Institute for Cancer Research (AICR) Cancer Prevention Recommendations and risk of 14 lifestyle-related cancers in the UK Biobank prospective cohort study

\ua9 2023, The Author(s).Background: The World Cancer Research Fund (WCRF)/American Institute for Cancer Research (AICR) Cancer Prevention Recommendations are lifestyle-based recommendations which aim to reduce cancer risk. This study investigated associations between adherence, assessed using a standardised scoring system, and the risk of all cancers combined and of 14 cancers for which there is strong evidence for links with aspects of lifestyle in the UK. Methods: We used data from 94,778 participants (53% female, mean age 56 years) from the UK Biobank. Total adherence scores (range 0–7 points) were derived from dietary, physical activity, and anthropometric data. Associations between total score and cancer risk (all cancers combined; and prostate, breast, colorectal, lung, uterine, liver, pancreatic, stomach, oesophageal, head and neck, ovarian, kidney, bladder, and gallbladder cancer) were investigated using Cox proportional hazard models, adjusting for age, sex, deprivation index, ethnicity, and smoking status. Results: Mean total score was 3.8 (SD 1.0) points. During a median follow-up of 8 years, 7296 individuals developed cancer. Total score was inversely associated with risk of all cancers combined (HR: 0.93; 95%CI: 0.90–0.95 per 1-point increment), as well as breast (HR: 0.90; 95%CI: 0.86–0.95), colorectal (HR: 0.90; 95%CI: 0.84–0.97), kidney (HR: 0.82; 95%CI: 0.72–0.94), oesophageal (HR: 0.84; 95%CI: 0.71–0.98), ovarian (HR: 0.76; 95%CI: 0.65–0.90), liver (HR: 0.78; 95%CI: 0.63–0.97), and gallbladder (HR: 0.70; 95%CI: 0.53–0.93) cancers. Conclusions: Greater adherence to lifestyle-based recommendations was associated with reduced risk of all cancers combined and of breast, colorectal, kidney, oesophageal, ovarian, liver, and gallbladder cancers. Our findings support compliance with the Cancer Prevention Recommendations for cancer prevention in the UK

Transnuclear TRP1-Specific CD8 T Cells with High or Low Affinity TCRs Show Equivalent Antitumor Activity

We have generated, via somatic cell nuclear transfer, two independent lines of transnuclear (TN) mice, using as nuclear donors CD8 T cells, sorted by tetramer staining, that recognize the endogenous melanoma antigen TRP1. These two lines of nominally identical specificity differ greatly in their affinity for antigen (TRP1(high) or TRP1(low)) as inferred from tetramer dissociation and peptide responsiveness. Ex vivo-activated CD8 T cells from either TRP1(high) or TRP1(low) mice show cytolytic activity in 3D tissue culture and in vivo, and slow the progression of subcutaneous B16 melanoma. Although naïve TRP1(low) CD8 T cells do not affect tumor growth, upon activation these cells function indistinguishably from TRP1(high) cells in vivo, limiting tumor cell growth and increasing mouse survival. The anti-tumor effect of both TRP1(high) and TRP1(low) CD8 T cells is enhanced in RAG-deficient hosts. However, tumor outgrowth eventually occurs, likely due to T cell exhaustion. The TRP1 TN mice are an excellent model for examining the functional attributes of T cells conferred by TCR affinity, and they may serve as a platform for screening immunomodulatory cancer therapies

Daily changes on seasonal ecophysiological responses of the intertidal brown macroalga Lessonia spicata: Implications of climate change

Global climate change is expected to have detrimental effects on coastal ecosystems, with impacts observable at the local and regional levels, depending on factors such as light, temperature, and nutrients. Shifts in dominance between primary producers that can capitalize on carbon availability for photosynthesis will have knock-on effects on marine ecosystems, affecting their ecophysiological responses and biological processes. Here, we study the ecophysiological vulnerability, photoacclimation capacity, and tolerance responses as ecophysiological responses of the intertidal kelp Lessonia spicata (Phaeophyceae, Laminariales) during a year through different seasons (autumn, winter, spring, and summer) in the Pacific Ocean (central Chile). Six different daily cycle experiments were carried out within each season. A battery of different biochemical assays associated with antioxidant responses and in-vivo chlorophyll a fluorescence parameter showed that during spring and summer, there was an increase in photosynthetic capacity in the macroalgae, although their responses varied depending on light and nutrient availability in the course of the year. Lessonia spicata showed maximal photosynthesis and a similar photoinhibition pattern in summer compared to the other seasons, and the contents of nitrate and phosphorous in seawater were less in winter. Thus, high irradiance during spring and summer displayed a higher maximal electron transport rate (ETRmax), irradiance of saturation (Ek), non-photochemical quenching (NPQmax), nitrogen and carbon contents, and photoprotector compound levels. Antioxidant activity increased also in summer, the seasonal period with the highest oxidative stress conditions, i.e., the highest level of hydrogen peroxide (H2O2). In contrast, under low irradiance, i.e., wintertime conditions, L. spicata demonstrated lower concentrations of the photosynthetic pigments such as chlorophyll a and carotenoids. Our study suggests that macroalgae that are subjected to increased irradiance and water temperature under lower nutrient availability mediated by seasonal changes (expected to worsen under climate change) respond with higher values of productivity, pigment contents, and photoprotective compounds. Thus, our findings strengthen the available evidence to predict that algae in the order Laminariales, specifically L. spicata (kelp), could better proliferate, with lower vulnerability and greater acclimation, than other marine species subject to future expected conditions associated with climate change.Financial and logistical support was granted by the project of Fondo Nacional de Desarrollo Científico y Tecnológico, Chile through grant Project FONDECYT, Chile N° 11180197, ANID, Chile - provided to Paula Celis - Plá