Spatio-temporal dynamics of quantum-well excitons

We investigate the lateral transport of excitons in ZnSe quantum wells by using time-resolved micro-photoluminescence enhanced by the introduction of a solid immersion lens. The spatial and temporal resolutions are 200 nm and 5 ps, respectively. Strong deviation from classical diffusion is observed up to 400 ps. This feature is attributed to the hot-exciton effects, consistent with previous experiments under cw excitation. The coupled transport-relaxation process of hot excitons is modelled by Monte Carlo simulation. We prove that two basic assumptions typically accepted in photoluminescence investigations on excitonic transport, namely (i) the classical diffusion model as well as (ii) the equivalence between the temporal and spatial evolution of the exciton population and of the measured photoluminescence, are not valid for low-temperature experiments.Comment: 8 pages, 6 figure

Systems-level analysis of age-related macular degeneration reveals global biomarkers and phenotype-specific functional networks

Abstract Background Age-related macular degeneration (AMD) is a leading cause of blindness that affects the central region of the retinal pigmented epithelium (RPE), choroid, and neural retina. Initially characterized by an accumulation of sub-RPE deposits, AMD leads to progressive retinal degeneration, and in advanced cases, irreversible vision loss. Although genetic analysis, animal models, and cell culture systems have yielded important insights into AMD, the molecular pathways underlying AMD's onset and progression remain poorly delineated. We sought to better understand the molecular underpinnings of this devastating disease by performing the first comparative transcriptome analysis of AMD and normal human donor eyes. Methods RPE-choroid and retina tissue samples were obtained from a common cohort of 31 normal, 26 AMD, and 11 potential pre-AMD human donor eyes. Transcriptome profiles were generated for macular and extramacular regions, and statistical and bioinformatic methods were employed to identify disease-associated gene signatures and functionally enriched protein association networks. Selected genes of high significance were validated using an independent donor cohort. Results We identified over 50 annotated genes enriched in cell-mediated immune responses that are globally over-expressed in RPE-choroid AMD phenotypes. Using a machine learning model and a second donor cohort, we show that the top 20 global genes are predictive of AMD clinical diagnosis. We also discovered functionally enriched gene sets in the RPE-choroid that delineate the advanced AMD phenotypes, neovascular AMD and geographic atrophy. Moreover, we identified a graded increase of transcript levels in the retina related to wound response, complement cascade, and neurogenesis that strongly correlates with decreased levels of phototransduction transcripts and increased AMD severity. Based on our findings, we assembled protein-protein interactomes that highlight functional networks likely to be involved in AMD pathogenesis. Conclusions We discovered new global biomarkers and gene expression signatures of AMD. These results are consistent with a model whereby cell-based inflammatory responses represent a central feature of AMD etiology, and depending on genetics, environment, or stochastic factors, may give rise to the advanced AMD phenotypes characterized by angiogenesis and/or cell death. Genes regulating these immunological activities, along with numerous other genes identified here, represent promising new targets for AMD-directed therapeutics and diagnostics. Please see related commentary: http://www.biomedcentral.com/1741-7015/10/21/abstrac

Global disparities in surgeons’ workloads, academic engagement and rest periods: the on-calL shIft fOr geNEral SurgeonS (LIONESS) study

: The workload of general surgeons is multifaceted, encompassing not only surgical procedures but also a myriad of other responsibilities. From April to May 2023, we conducted a CHERRIES-compliant internet-based survey analyzing clinical practice, academic engagement, and post-on-call rest. The questionnaire featured six sections with 35 questions. Statistical analysis used Chi-square tests, ANOVA, and logistic regression (SPSS® v. 28). The survey received a total of 1.046 responses (65.4%). Over 78.0% of responders came from Europe, 65.1% came from a general surgery unit; 92.8% of European and 87.5% of North American respondents were involved in research, compared to 71.7% in Africa. Europe led in publishing research studies (6.6 ± 8.6 yearly). Teaching involvement was high in North America (100%) and Africa (91.7%). Surgeons reported an average of 6.7 ± 4.9 on-call shifts per month, with European and North American surgeons experiencing 6.5 ± 4.9 and 7.8 ± 4.1 on-calls monthly, respectively. African surgeons had the highest on-call frequency (8.7 ± 6.1). Post-on-call, only 35.1% of respondents received a day off. Europeans were most likely (40%) to have a day off, while African surgeons were least likely (6.7%). On the adjusted multivariable analysis HDI (Human Development Index) (aOR 1.993) hospital capacity > 400 beds (aOR 2.423), working in a specialty surgery unit (aOR 2.087), and making the on-call in-house (aOR 5.446), significantly predicted the likelihood of having a day off after an on-call shift. Our study revealed critical insights into the disparities in workload, access to research, and professional opportunities for surgeons across different continents, underscored by the HDI

Crisis Management and Security Program (CMS) (Semester Unknown) IPRO 370

The IIT IPRO 370 Crisis Management and Security Program (CMS) is in its fourth stage of development. The current goal is to further develop the capabilities of our web based program that can be used by organizations to assist when determining how well their crisis management plans stand up to different methodologies, assessments, and scenarios during the testing process. Also to start marketing our web site to attract a community of many users to assist in the growth of the CMS program. The initial grant for this project was funded by the Homeland Security Innovation & Entrepreneurship Center. Ms. Irene Rozansky, CEO and founder of R&A Crisis Management Services Inc. will be our sponsor to ensure that we develop a program able to test existing crisis management plans for companies, organizations, and individuals who lack a response ready approach in times of crisis.Deliverable

Crisis Management and Security Program (CMS) (Semester Unknown) IPRO 370: Crisis Management and Security Program IPRO 370 Final Presentation Sp08

The IIT IPRO 370 Crisis Management and Security Program (CMS) is in its fourth stage of development. The current goal is to further develop the capabilities of our web based program that can be used by organizations to assist when determining how well their crisis management plans stand up to different methodologies, assessments, and scenarios during the testing process. Also to start marketing our web site to attract a community of many users to assist in the growth of the CMS program. The initial grant for this project was funded by the Homeland Security Innovation & Entrepreneurship Center. Ms. Irene Rozansky, CEO and founder of R&A Crisis Management Services Inc. will be our sponsor to ensure that we develop a program able to test existing crisis management plans for companies, organizations, and individuals who lack a response ready approach in times of crisis.Deliverable

Crisis Management and Security Program (CMS) (Semester Unknown) IPRO 370: Crisis Management and Security Program IPRO 370 Brochure2 Sp08

The IIT IPRO 370 Crisis Management and Security Program (CMS) is in its fourth stage of development. The current goal is to further develop the capabilities of our web based program that can be used by organizations to assist when determining how well their crisis management plans stand up to different methodologies, assessments, and scenarios during the testing process. Also to start marketing our web site to attract a community of many users to assist in the growth of the CMS program. The initial grant for this project was funded by the Homeland Security Innovation & Entrepreneurship Center. Ms. Irene Rozansky, CEO and founder of R&A Crisis Management Services Inc. will be our sponsor to ensure that we develop a program able to test existing crisis management plans for companies, organizations, and individuals who lack a response ready approach in times of crisis.Deliverable

Crisis Management and Security Program (CMS) (Semester Unknown) IPRO 370: Crisis Management and Security Program IPRO 370 Ethics Sp08

The IIT IPRO 370 Crisis Management and Security Program (CMS) is in its fourth stage of development. The current goal is to further develop the capabilities of our web based program that can be used by organizations to assist when determining how well their crisis management plans stand up to different methodologies, assessments, and scenarios during the testing process. Also to start marketing our web site to attract a community of many users to assist in the growth of the CMS program. The initial grant for this project was funded by the Homeland Security Innovation & Entrepreneurship Center. Ms. Irene Rozansky, CEO and founder of R&A Crisis Management Services Inc. will be our sponsor to ensure that we develop a program able to test existing crisis management plans for companies, organizations, and individuals who lack a response ready approach in times of crisis.Deliverable

Crisis Management and Security Program (CMS) (Semester Unknown) IPRO 370: Crisis Management and Security Program IPRO 370 Final Report Sp08

The IIT IPRO 370 Crisis Management and Security Program (CMS) is in its fourth stage of development. The current goal is to further develop the capabilities of our web based program that can be used by organizations to assist when determining how well their crisis management plans stand up to different methodologies, assessments, and scenarios during the testing process. Also to start marketing our web site to attract a community of many users to assist in the growth of the CMS program. The initial grant for this project was funded by the Homeland Security Innovation & Entrepreneurship Center. Ms. Irene Rozansky, CEO and founder of R&A Crisis Management Services Inc. will be our sponsor to ensure that we develop a program able to test existing crisis management plans for companies, organizations, and individuals who lack a response ready approach in times of crisis.Deliverable

Crisis Management and Security Program (CMS) (Semester Unknown) IPRO 370: Crisis Management and Security Program IPRO 370 Midterm Report Sp08

The IIT IPRO 370 Crisis Management and Security Program (CMS) is in its fourth stage of development. The current goal is to further develop the capabilities of our web based program that can be used by organizations to assist when determining how well their crisis management plans stand up to different methodologies, assessments, and scenarios during the testing process. Also to start marketing our web site to attract a community of many users to assist in the growth of the CMS program. The initial grant for this project was funded by the Homeland Security Innovation & Entrepreneurship Center. Ms. Irene Rozansky, CEO and founder of R&A Crisis Management Services Inc. will be our sponsor to ensure that we develop a program able to test existing crisis management plans for companies, organizations, and individuals who lack a response ready approach in times of crisis.Deliverable

Crisis Management and Security Program (CMS) (Semester Unknown) IPRO 370: Crisis Management and Security Program IPRO 370 Brochure1 Sp08

The IIT IPRO 370 Crisis Management and Security Program (CMS) is in its fourth stage of development. The current goal is to further develop the capabilities of our web based program that can be used by organizations to assist when determining how well their crisis management plans stand up to different methodologies, assessments, and scenarios during the testing process. Also to start marketing our web site to attract a community of many users to assist in the growth of the CMS program. The initial grant for this project was funded by the Homeland Security Innovation & Entrepreneurship Center. Ms. Irene Rozansky, CEO and founder of R&A Crisis Management Services Inc. will be our sponsor to ensure that we develop a program able to test existing crisis management plans for companies, organizations, and individuals who lack a response ready approach in times of crisis.Deliverable