| 1. |
- Poley, L., et al.
(författare)
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The ABC130 barrel module prototyping programme for the ATLAS strip tracker
- 2020
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Ingår i: Journal of Instrumentation. - : IOP PUBLISHING LTD. - 1748-0221. ; 15:9
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Tidskriftsartikel (refereegranskat)abstract
- For the Phase-II Upgrade of the ATLAS Detector [1], its Inner Detector, consisting of silicon pixel, silicon strip and transition radiation sub-detectors, will be replaced with an all new 100% silicon tracker, composed of a pixel tracker at inner radii and a strip tracker at outer radii. The future ATLAS strip tracker will include 11,000 silicon sensor modules in the central region (barrel) and 7,000 modules in the forward region (end-caps), which are foreseen to be constructed over a period of 3.5 years. The construction of each module consists of a series of assembly and quality control steps, which were engineered to be identical for all production sites. In order to develop the tooling and procedures for assembly and testing of these modules, two series of major prototyping programs were conducted: an early program using readout chips designed using a 250 nm fabrication process (ABCN-250) [2, 3] and a subsequent program using a follow-up chip set made using 130 nm processing (ABC130 and HCC130 chips). This second generation of readout chips was used for an extensive prototyping program that produced around 100 barrel-type modules and contributed significantly to the development of the final module layout. This paper gives an overview of the components used in ABC130 barrel modules, their assembly procedure and findings resulting from their tests.
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| 2. |
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| 3. |
- Santangelo, James S., et al.
(författare)
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Global urban environmental change drives adaptation in white clover
- 2022
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 375
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Tidskriftsartikel (refereegranskat)abstract
- Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural dines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale.
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| 4. |
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| 5. |
- Mangold, N., et al.
(författare)
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Perseverance rover reveals an ancient delta-lake system and flood deposits at Jezero crater, Mars
- 2021
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 374:6568
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Tidskriftsartikel (refereegranskat)abstract
- Observations from orbital spacecraft have shown that Jezero crater on Mars contains a prominent fan-shaped body of sedimentary rock deposited at its western margin. The Perseverance rover landed in Jezero crater in February 2021. We analyze images taken by the rover in the 3 months after landing. The fan has outcrop faces, which were invisible from orbit, that record the hydrological evolution of Jezero crater. We interpret the presence of inclined strata in these outcrops as evidence of deltas that advanced into a lake. In contrast, the uppermost fan strata are composed of boulder conglomerates, which imply deposition by episodic high-energy floods. This sedimentary succession indicates a transition from sustained hydrologic activity in a persistent lake environment to highly energetic short-duration fluvial flows.
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| 6. |
- Stack, K. M., et al.
(författare)
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Sedimentology and Stratigraphy of the Shenandoah Formation, Western Fan, Jezero Crater, Mars
- 2024
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Ingår i: Journal of Geophysical Research: Planets. - 2169-9097. ; 129:2
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Tidskriftsartikel (refereegranskat)abstract
- Sedimentary fans are key targets of exploration on Mars because they record the history of surface aqueous activity and habitability. The sedimentary fan extending from the Neretva Vallis breach of Jezero crater's western rim is one of the Mars 2020 Perseverance rover's main exploration targets. Perseverance spent ∼250 sols exploring and collecting seven rock cores from the lower ∼25 m of sedimentary rock exposed within the fan's eastern scarp, a sequence informally named the “Shenandoah” formation. This study describes the sedimentology and stratigraphy of the Shenandoah formation at two areas, “Cape Nukshak” and “Hawksbill Gap,” including a characterization, interpretation, and depositional framework for the facies that comprise it. The five main facies of the Shenandoah formation include: laminated mudstone, laminated sandstone, low-angle cross stratified sandstone, thin-bedded granule sandstone, and thick-bedded granule-pebble sandstone and conglomerate. These facies are organized into three facies associations (FA): FA1, comprised of laminated and soft sediment-deformed sandstone interbedded with broad, unconfined coarser-grained granule and pebbly sandstone intervals; FA2, comprised predominantly of laterally extensive, soft-sediment deformed laminated, sulfate-bearing mudstone with lenses of low-angle cross-stratified and scoured sandstone; and FA3, comprised of dipping planar, thin-bedded sand-gravel couplets. The depositional model favored for the Shenandoah formation involves the transition from a sand-dominated distal alluvial fan setting (FA1) to a stable, widespread saline lake (FA2), followed by the progradation of a river delta system (FA3) into the lake basin. This sequence records the initiation of a relatively long-lived, habitable lacustrine and deltaic environment within Jezero crater.
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| 7. |
- Vaniman, D.T., et al.
(författare)
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Mineralogy of a mudstone at Yellowknife Bay, Gale Crater, Mars
- 2014
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 343:6169
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Tidskriftsartikel (refereegranskat)abstract
- Sedimentary rocks at Yellowknife Bay (Gale crater) on Mars include mudstone sampled by the Curiosity rover. The samples, John Klein and Cumberland, contain detrital basaltic minerals, calcium sulfates, iron oxide or hydroxides, iron sulfides, amorphous material, and trioctahedral smectites. The John Klein smectite has basal spacing of ~10 angstroms, indicating little interlayer hydration. The Cumberland smectite has basal spacing at both ~13.2 and ~10 angstroms. The larger spacing suggests a partially chloritized interlayer or interlayer magnesium or calcium facilitating H2O retention. Basaltic minerals in the mudstone are similar to those in nearby eolian deposits. However, the mudstone has far less Fe-forsterite, possibly lost with formation of smectite plus magnetite. Late Noachian/Early Hesperian or younger age indicates that clay mineral formation on Mars extended beyond Noachian time.
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| 8. |
- Grotzinger, J.P., et al.
(författare)
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A habitable fluvio-lacustrine environment at Yellowknife Bay, Gale Crater, Mars
- 2014
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 343:6169
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Tidskriftsartikel (refereegranskat)abstract
- The Curiosity rover discovered fine-grained sedimentary rocks, which are inferred to represent an ancient lake and preserve evidence of an environment that would have been suited to support a martian biosphere founded on chemolithoautotrophy. This aqueous environment was characterized by neutral pH, low salinity, and variable redox states of both iron and sulfur species. Carbon, hydrogen, oxygen, sulfur, nitrogen, and phosphorus were measured directly as key biogenic elements; by inference, phosphorus is assumed to have been available. The environment probably had a minimum duration of hundreds to tens of thousands of years. These results highlight the biological viability of fluvial-lacustrine environments in the post-Noachian history of Mars.
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| 9. |
- Caizergues, Aude E., et al.
(författare)
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Does urbanisation lead to parallel demographic shifts across the world in a cosmopolitan plant?
- 2024
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Ingår i: Molecular Ecology. - 0962-1083 .- 1365-294X. ; 33:7
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Tidskriftsartikel (refereegranskat)abstract
- Urbanisation is occurring globally, leading to dramatic environmental changes that are altering the ecology and evolution of species. In particular, the expansion of human infrastructure and the loss and fragmentation of natural habitats in cities is predicted to increase genetic drift and reduce gene flow by reducing the size and connectivity of populations. Alternatively, the 'urban facilitation model' suggests that some species will have greater gene flow into and within cities leading to higher diversity and lower differentiation in urban populations. These alternative hypotheses have not been contrasted across multiple cities. Here, we used the genomic data from the GLobal Urban Evolution project (GLUE), to study the effects of urbanisation on non-adaptive evolutionary processes of white clover (Trifolium repens) at a global scale. We found that white clover populations presented high genetic diversity and no evidence of reduced Ne linked to urbanisation. On the contrary, we found that urban populations were less likely to experience a recent decrease in effective population size than rural ones. In addition, we found little genetic structure among populations both globally and between urban and rural populations, which showed extensive gene flow between habitats. Interestingly, white clover displayed overall higher gene flow within urban areas than within rural habitats. Our study provides the largest comprehensive test of the demographic effects of urbanisation. Our results contrast with the common perception that heavily altered and fragmented urban environments will reduce the effective population size and genetic diversity of populations and contribute to their isolation.
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| 10. |
- Holm-Alwmark, S., et al.
(författare)
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Stratigraphic Relationships in Jezero Crater, Mars : Constraints on the Timing of Fluvial-Lacustrine Activity From Orbital Observations
- 2021
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Ingår i: Journal of Geophysical Research: Planets. - 2169-9097. ; 126:7
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Tidskriftsartikel (refereegranskat)abstract
- On February 18, 2021 NASA's Perseverance rover landed in Jezero crater, located at the northwestern edge of the Isidis basin on Mars. The uppermost surface of the present-day crater floor is dominated by a distinct geologic assemblage previously referred to as the dark-toned floor. It consists of a smooth, dark-toned unit overlying and variably covering light-toned, roughly eroded deposits showing evidence of discrete layers. In this study, we investigated the stratigraphic relations between materials that comprise this assemblage, the main western delta deposit, as well as isolated mesas located east of the main delta body that potentially represent delta remnants. A more detailed classification and differentiation of crater floor units in Jezero and determination of their relative ages is vital for the understanding of the geologic evolution of the crater system, and determination of the potential timeline and environments of habitability. We have investigated unit contacts using topographic profiles and DEMs as well as the distribution of small craters and fractures on the youngest portions of the crater floor. Our results indicate that at least some of the deltaic deposition in Jezero postdates emplacement of the uppermost surface of the crater floor assemblage. The inferred age of the floor assemblage can therefore help to constrain the timing of the Jezero fluviolacustrine system, wherein at least some lake activity postdates the age of the uppermost crater floor. We present hypotheses that can be tested by Perseverance and can be used to advance our knowledge of the geologic evolution of the area.
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| 11. |
- Quantin-Nataf, C., et al.
(författare)
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The Complex Exhumation History of Jezero Crater Floor Unit and Its Implication for Mars Sample Return
- 2023
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Ingår i: Journal of Geophysical Research: Planets. - 2169-9097. ; 128:6
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Tidskriftsartikel (refereegranskat)abstract
- During the first year of NASA's Mars 2020 mission, Perseverance rover has investigated the dark crater floor unit of Jezero crater and four samples of this unit have been collected. The focus of this paper is to assess the potential of these samples to calibrate the crater-based Martian chronology. We first review the previous estimation of crater-based model age of this unit. Then, we investigate the impact crater density distribution across the floor unit. It reveals that the crater density is heterogeneous from areas which have been exposed to the bombardment during the last 3 Ga to areas very recently exposed to bombardment. It suggests a complex history of exposure to impact cratering. We also display evidence of several remnants of deposits on the top of the dark floor unit across Jezero below which the dark floor unit may have been buried. We propose the following scenario of burying/exhumation: the dark floor unit would have been initially buried below a unit that was a few tens of meters thick. This unit then gradually eroded away due to Aeolian processes from the northeast to the west, resulting in uneven exposure to impact bombardment over 3 Ga. A cratering model reproducing this scenario confirms the feasibility of this hypothesis. Due to the complexity of its exposure history, the Jezero dark crater floor unit will require additional detailed analysis to understand how the Mars 2020 mission samples of the crater floor can be used to inform the Martian cratering chronology.
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| 12. |
- Silver Karcioglu, Amanda L., et al.
(författare)
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Emerging Imaging Technologies for Parathyroid Gland Identification and Vascular Assessment in Thyroid Surgery : A Review from the American Head and Neck Society Endocrine Surgery Section
- 2023
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Ingår i: JAMA Otolaryngology - Head and Neck Surgery. - : American Medical Association (AMA). - 2168-6181. ; 149:3, s. 253-260
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Forskningsöversikt (refereegranskat)abstract
- Importance: Identification and preservation of parathyroid glands (PGs) remain challenging despite advances in surgical techniques. Considerable morbidity and even mortality result from hypoparathyroidism caused by devascularization or inadvertent removal of PGs. Emerging imaging technologies hold promise to improve identification and preservation of PGs during thyroid surgery. Observation: This narrative review (1) comprehensively reviews PG identification and vascular assessment using near-infrared autofluorescence (NIRAF) - both label free and in combination with indocyanine green - based on a comprehensive literature review and (2) offers a manual for possible implementation these emerging technologies in thyroid surgery. Conclusions and Relevance: Emerging technologies hold promise to improve PG identification and preservation during thyroidectomy. Future research should address variables affecting the degree of fluorescence in NIRAF, standardization of signal quantification, definitions and standardization of parameters of indocyanine green injection that correlate with postoperative PG function, the financial effect of these emerging technologies on near-term and longer-term costs, the adoption learning curve and effect on surgical training, and long-term outcomes of key quality metrics in adequately powered randomized clinical trials evaluating PG preservation.
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| 13. |
- Falahee, Marie, et al.
(författare)
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Patients' Perceptions of Their Relatives' Risk of Developing Rheumatoid Arthritis and of the Potential for Risk Communication, Prediction, and Modulation
- 2017
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Ingår i: Arthritis care & research. - : WILEY. - 2151-464X .- 2151-4658. ; 69:10, s. 1558-1565
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To understand the perspectives of patients with rheumatoid arthritis (RA) about the risk of their relatives developing RA in the future, and about communicating with their relatives concerning risk and its modulation.Methods: Twenty-one RA patients took part in semistructured interviews.Results: Participants reported willingness to communicate with relatives about their risk of developing RA, but described choosing which relatives to communicate with, on the basis of the relatives' perceived receptivity to such risk information. Participants described the potential for risk information to cause negative emotions. Some participants did not consider RA to be hereditable, and few reported smoking as a risk factor. Patients described a lack of public awareness about the causes of RA and the negative impact that RA has on the quality of life. Awareness of this negative impact was identified as an important driver for predictive and preventive strategies. Participants held positive perceptions of predictive testing for RA, though the results of predictive tests were conceptualized as having a high degree of accuracy. Negative views of predictive testing were associated with an appreciation of the probabilistic nature of risk information. Participants felt that their relatives would prefer lifestyle modification over medication as a risk reduction strategy.Conclusion: Information about risk factors for RA, and the potential impact of RA on the quality of life, is needed to support family communication about RA risk. Management of expectations is needed in relation to the probabilistic nature of risk information, and appropriate support should be provided for negative psychological outcomes.
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| 14. |
- Litvak, M.L., et al.
(författare)
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Local variations of bulk hydrogen and chlorine-equivalent neutron absorption content measured at the contact between the Sheepbed and Gillespie Lake units in Yellowknife Bay, Gale Crater, using the DAN instrument onboard Curiosity
- 2014
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Ingår i: Journal of Geophysical Research - Planets. - 2169-9097 .- 2169-9100. ; 119:6, s. 1259-1275
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Tidskriftsartikel (refereegranskat)abstract
- Data gathered with the Dynamic Albedo of Neutron (DAN) instrument onboard rover Curiosity were analyzed for variations in subsurface neutron flux and tested for possible correlation with local geological context. A special DAN observation campaign was executed, in which 18 adjacent DAN active measurements were acquired every 0.75–1.0 m to search for the variations of subsurface hydrogen content along a 15 m traverse across geologic contacts between the Sheepbed and Gillespie Lake members of the Yellowknife Bay formation. It was found that several subunits in Sheepbed and Gillespie Lake could be characterized with different depth distributions of water-equivalent hydrogen (WEH) and different chlorine-equivalent abundance responsible for the distribution of neutron absorption elements. The variations of the average WEH at the top 60 cm of the subsurface are estimated at up to 2–3%. Chlorine-equivalent neutron absorption abundances ranged within 0.8–1.5%. The largest difference in WEH and chlorine-equivalent neutron absorption distribution is found between Sheepbed and Gillespie Lake.
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| 15. |
- O'Meara, Elaine, et al.
(författare)
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Characterization of the chromosomal translocation t(10;17)(q22;p13) in clear cell sarcoma of kidney
- 2012
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Ingår i: Journal of Pathology. - : Wiley. - 0022-3417. ; 227:1, s. 72-80
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Tidskriftsartikel (refereegranskat)abstract
- Clear cell sarcoma of kidney (CCSK) is classified as a tumour of unfavourable histology by the National Wilms' Tumor Study Group. It has worse clinical outcomes than Wilms' tumour. Virtually nothing is known about CCSK biology, as there have been very few genetic aberrations identified to act as pointers in this cancer. Three cases of CCSK bearing a chromosomal translocation, t(10;17)(q22;p13), have been individually reported but not further investigated to date. The aim of this research was to characterize t(10;17)(q22;p13) in CCSK to identify the genes involved in the translocation breakpoints. Using fluorescently labelled bacterial artificial chromosomes (BACs) and a chromosome-walking strategy on an index case of CCSK with t(10;17)(q22;p13) by karyotype, we identified the chromosomal breakpoints on 17p13.3 and 10q22.3. The translocation results in rearrangement of YWHAE on chromosome 17 and FAM22 on chromosome 10, producing an in-frame fusion transcript of similar to 3 kb, incorporating exons 15 of YWHAE and exons 2-7 of FAM22, as determined by RT-PCR using YWHAE- and FAM22-specific primers. The YWHAE-FAM22 transcript was detected in six of 50 further CCSKs tested, therefore showing an overall incidence of 12% in our cohort. No transcript-positive cases presented with stage I disease, despite this being the stage for 31% of our cohort. Tumour cellularity was significantly higher in the cases that were transcript-positive. Based on the chromosome 10 breakpoint identified by FISH and the sequences of the full-length transcripts obtained, the FAM22 members involved in the translocation in these CCSK cases include FAM22B and FAM22E. Elucidation of the role of YWHAE-FAM22 in CCSK will assist development of more efficient and targeted therapies for this childhood cancer, which currently has poor outcomes. Copyright (c) 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
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| 16. |
- Simons, Gwenda, et al.
(författare)
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Perceptions of first-degree relatives of patients with rheumatoid arthritis about lifestyle modifications and pharmacological interventions to reduce the risk of rheumatoid arthritis development : a qualitative interview study
- 2018
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Ingår i: BMC Rheumatology. - : Springer Nature. - 2520-1026. ; 2:1
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundThere is increasing interest in the identification of people at risk of rheumatoid arthritis (RA) to monitor the emergence of early symptoms (and thus allow early therapy), offer lifestyle advice to reduce the impact of environmental risk factors and potentially offer preventive pharmacological treatment for those at high risk. Close biological relatives of people with RA are at an increased risk of developing RA and are therefore potential candidates for research studies, screening initiatives and preventive interventions. To ensure the success of approaches of this kind, a greater understanding of the perceptions of this group relating to preventive measures is needed.MethodsTwenty-four first-degree relatives of patients with an existing diagnosis of RA from the UK, three from Germany and seven from Austria (age: 21-67 years) took part in semi-structured interviews exploring their perceptions of RA risk, preventive medicine and lifestyle changes to reduce RA risk. Interviews were audio-recorded, transcribed verbatim and analysed using thematic analysis.ResultsMany first-degree relatives indicated that they anticipated being happy to make lifestyle changes such as losing weight or changing their diet to modify their risk of developing RA. Participants further indicated that in order to make any lifestyle changes it would be useful to know their personal risk of developing RA. Others implied they would not contemplate making lifestyle changes, including stopping smoking, unless this would significantly reduce or eliminate their risk of developing RA. Many first-degree relatives had more negative perceptions about taking preventive medication to reduce their risk of RA, and listed concerns about potential side effects as one of the reasons for not wanting to take preventive medicines. Others would be more willing to consider drug interventions although some indicated that they would wish to wait until symptoms developed.ConclusionsInformation targeted at those considered to be at risk of RA should contain information about RA, the extent to which risk can be quantified at an individual level and how risk levels may differ depending on whether early symptoms are present. The benefits (and risks) of lifestyle changes and pharmacological interventions as potential preventive measures should be clearly described.
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| 17. |
- Stack, Rebecca J., et al.
(författare)
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Perceptions of risk and predictive testing held by the first-degree relatives of patients with rheumatoid arthritis in England, Austria and Germany : a qualitative study
- 2016
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Ingår i: BMJ Open. - : BMJ. - 2044-6055. ; 6:6
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Tidskriftsartikel (refereegranskat)abstract
- Objectives The family members of patients with rheumatoid arthritis (RA) are at increased risk of developing RA and are potential candidates for predictive testing. This study explored the perceptions of first-degree relatives of people with RA about being at risk of RA and engaging in predictive testing. Methods 34 first-degree relatives (siblings and offspring) of patients with RA from the UK, Germany and Austria participated in semistructured interviews about their perceptions of RA risk and the prospect of predictive testing. Interviews were audio-recorded, transcribed verbatim and analysed using thematic analysis. Results First-degree relatives were aware of their susceptibility to RA, but were unsure of the extent of their risk. When considering their future risk, some relatives were concerned about the potential impact that RA would have on their lives. Relatives were concerned that knowing their actual risk would increase their anxiety and would affect decisions about their future. Also, relatives were concerned about the levels of uncertainty associated with predictive testing. Those in favour of knowing their future risk felt that they would need additional support to understand the risk information and cope with the emotional impact of this information. Conclusions Identifying individuals at risk of RA may allow targeted interventions to reduce the risk and consequence of future disease; however, relatives have concerns about predictive testing and risk information. The development of strategies to quantify and communicate risk needs to take these views into account and incorporate approaches to mitigate concerns and minimise the psychological impact of risk information.
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| 18. |
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| 19. |
- Sun, Vivian Z., et al.
(författare)
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Overview and Results From the Mars 2020 Perseverance Rover's First Science Campaign on the Jezero Crater Floor
- 2023
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Ingår i: Journal of Geophysical Research: Planets. - : John Wiley and Sons Inc. - 2169-9097 .- 2169-9100. ; 128:6
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Tidskriftsartikel (refereegranskat)abstract
- The Mars 2020 Perseverance rover landed in Jezero crater on 18 February 2021. After a 100-sol period of commissioning and the Ingenuity Helicopter technology demonstration, Perseverance began its first science campaign to explore the enigmatic Jezero crater floor, whose igneous or sedimentary origins have been much debated in the scientific community. This paper describes the campaign plan developed to explore the crater floor's Máaz and Séítah formations and summarizes the results of the campaign between sols 100–379. By the end of the campaign, Perseverance had traversed more than 5 km, created seven abrasion patches, and sealed nine samples and a witness tube. Analysis of remote and proximity science observations show that the Máaz and Séítah formations are igneous in origin and composed of five and two geologic members, respectively. The Séítah formation represents the olivine-rich cumulate formed from differentiation of a slowly cooling melt or magma body, and the Máaz formation likely represents a separate series of lava flows emplaced after Séítah. The Máaz and Séítah rocks also preserve evidence of multiple episodes of aqueous alteration in secondary minerals like carbonate, Fe/Mg phyllosilicates, sulfates, and perchlorate, and surficial coatings. Post-emplacement processes tilted the rocks near the Máaz-Séítah contact and substantial erosion modified the crater floor rocks to their present-day expressions. Results from this crater floor campaign, including those obtained upon return of the collected samples, will help to build the geologic history of events that occurred in Jezero crater and provide time constraints on the formation of the Jezero delta.
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| 20. |
- Unger, Eva, et al.
(författare)
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Sequential "click'' functionalization of mesoporous titania for energy-relay dye enhanced dye-sensitized solar cells
- 2015
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Ingår i: Physical Chemistry Chemical Physics. - : Royal Society of Chemistry (RSC). - 1463-9084 .- 1463-9076. ; 17:9, s. 6565-6571
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Tidskriftsartikel (refereegranskat)abstract
- Energy relay dyes (ERDs) have been investigated previously as a mean to achieve panchromatic spectral response in dye-sensitized solar cells via energy transfer. To reduced the distance between the ERDs and energy-accepting injection dyes (IDs) on the surface of a mesoporous titanium dioxide electrode, the ERDs were immobilized adjacent to the IDs via a sequential functionalization approach. In the first step, azidobenzoic acid molecules were co-adsorbed on the mesoporous titanium dioxide surface with the ID. In the second step, the highly selective copper(I)-catalyzed 1,3-dipolar azide-alkyne cycloaddition "click'' reaction was employed to couple an alkyne-functionalized ERD to the azidobenzoic acid monolayer. The cycloaddition step in the mesoporous electrode was slowed dramatically due to reactants and catalysts forming agglomerates. In solar cell devices, the close proximity between the surface-immobilized ERD and energy-accepting squaraine sensitizer dyes results in energy transfer efficiencies of up to 91%. The relative improvement in device performance due to the additional ERD spectral response was 124%, which is among the highest reported. The sequential functionalization approach described herein is transferrable to other applications requiring the functionalization of electrodes with complex molecules.
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