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The development of efficient and low-cost catalysts is essential for photocatalysis; however, the intrinsically low photocatalytic efficiency as well as the difficulty in using and recycling photocatalysts in powder morphology greatly limit their practical performance. Herein, we describe quasi-homogeneous photocatalysis to overcome these two limitations by constructing ultrastiff, hierarchically porous, and photoactive aerogels of conjugated microporous polymers (CMPs). The CMP aerogels exhibit low density but high stiffness beyond 105 m2 s-2, outperforming most low-density materials. Extraordinary stiffness ensures their use as robust scaffolds for scaled photocatalysis and recycling without damage at the macroscopic level. A challenging but desirable reaction for direct deaminative borylation is demonstrated using CMP aerogel-based quasi-homogeneous photocatalysis with gram-scale productivity and record-high efficiency under ambient conditions. Combined terahertz and transient absorption spectroscopic studies unveil the generation of high-mobility free carriers and long-lived excitonic species in the CMP aerogels, underlying the observed superior catalytic performance.
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High-risk HPV infection accounts for 99.7% of cervical cancer, over 90% of anal cancer, 50% of head and neck cancers, 40% of vulvar cancer, and some cases of vaginal and penile cancer, contributing to approximately 5% of cancers worldwide. The development of cancer is a complex, multi-step process characterized by dysregulation of signaling pathways and alterations in metabolic pathways. Extensive research has demonstrated that metabolic reprogramming plays a key role in the progression of various cancers, such as cervical, head and neck, bladder, and prostate cancers, providing the material and energy foundation for rapid proliferation and migration of cancer cells. Metabolic reprogramming of tumor cells allows for the rapid generation of ATP, aiding in meeting the high energy demands of HPV-related cancer cell proliferation. The interaction between Human Papillomavirus (HPV) and its associated cancers has become a recent focus of investigation. The impact of HPV on cellular metabolism has emerged as an emerging research topic. A significant body of research has shown that HPV influences relevant metabolic signaling pathways, leading to cellular metabolic alterations. Exploring the underlying mechanisms may facilitate the discovery of biomarkers for diagnosis and treatment of HPV-associated diseases. In this review, we introduced the molecular structure of HPV and its replication process, discussed the diseases associated with HPV infection, described the energy metabolism of normal cells, highlighted the metabolic features of tumor cells, and provided an overview of recent advances in potential therapeutic targets that act on cellular metabolism. We discussed the potential mechanisms underlying these changes. This article aims to elucidate the role of Human Papillomavirus (HPV) in reshaping cellular metabolism and the application of metabolic changes in the research of related diseases. Targeting cancer metabolism may serve as an effective strategy to support traditional cancer treatments, as metabolic reprogramming is crucial for malignant transformation in cancer.
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Developing efficient artificial photocatalysts for the biomimetic photocatalytic production of molecular materials, including medicines and clean energy carriers, remains a fundamentally and technologically essential challenge. Hydrogen peroxide is widely used in chemical synthesis, medical disinfection, and clean energy. However, the current industrial production, predominantly by anthraquinone oxidation, suffers from hefty energy penalties and toxic byproducts. Herein, we report the efficient photocatalytic production of hydrogen peroxide by protonation-induced dispersible porous polymers with good charge-carrier transport properties. Significant photocatalytic hydrogen peroxide generation occurs under ambient conditions at an unprecedented rate of 23.7 mmol g-1 h-1 and an apparent quantum efficiency of 11.3% at 450 nm. Combined simulations and spectroscopies indicate that sub-picosecond ultrafast electron "localization" from both free carriers and exciton states at the catalytic reaction centers underlie the remarkable photocatalytic performance of the dispersible porous polymers.
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Singlet fission (SF) presents an attractive solution to overcome the Shockley-Queisser limit of single-junction solar cells. The conversion from an initial singlet state to final triplet is mediated by the correlated triplet pair state 1(T1T1). Despite significant advancement on 1(T1T1) properties and its role in SF, a comprehensive understanding of the energetic landscape during SF is still unclear. Here, we study an unconventional SF system with excited-state aromaticity, i.e., cyano-substituted dipyrrolonaphtheridinedione derivative (DPND-CN), using time-resolved spectroscopy as a function of the temperature. We demonstrate that the population transfer from S1 to 1(T1T1) is driven by a time-dependent exothermicity resulting from the coherent coupling between electronic and spin degrees of freedom. This is followed by thermal-activated dissociation of 1(T1T1) to yield free triplets. Our results provide some new insight into the SF mechanism, which may guide the development of new efficient and stable SF materials for practical applications.
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Ovarian cancer (OC) is among the most common gynecologic malignancies with a poor prognosis and a high mortality rate. Most patients are diagnosed at an advanced stage (stage III or IV), with 5-year survival rates ranging from 25% to 47% worldwide. Surgical resection and first-line chemotherapy are the main treatment modalities for OC. However, patients usually relapse within a few years of initial treatment due to resistance to chemotherapy. Cell-based therapies, particularly adoptive T-cell therapy and chimeric antigen receptor T (CAR-T) cell therapy, represent an alternative immunotherapy approach with great potential for hematologic malignancies. However, the use of CAR-T-cell therapy for the treatment of OC is still associated with several difficulties. In this review, we comprehensively discuss recent innovations in CAR-T-cell engineering to improve clinical efficacy, as well as strategies to overcome the limitations of CAR-T-cell therapy in OC.
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Neoplasias Ovarianas , Receptores de Antígenos Quiméricos , Humanos , Feminino , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos de Linfócitos T , Neoplasias Ovarianas/terapia , Linfócitos T , Terapia Baseada em Transplante de Células e TecidosRESUMO
BACKGROUND: The purpose of this study was to report the rare case of a pregnant woman with congenital dysfibrinogenemia (CD) misdiagnosed as acute fatty liver. She was treated according to the principles of acute fatty liver but achieved good clinical results. CASE SUMMARY: A 30-year-old woman presented with 39 (6/7) wk of menopause and 6 h of irregular abdominal pain and attended our hospital. Emergency surgery was performed due to fetal distress. Postoperative management followed the treatment principle of acute fatty liver. DNA sequencing was carried out on the pregnant woman and her pedigree. Coagulation values of the patient on admission were prothrombin time 33.7 s, activated partial thromboplastin time 60.4 s, thrombin time 45.2 s, and fibrinogen 0.60 g/L. DNA sequencing results showed that the woman carried a pathogenic heterozygous variation of the fibrinogen alpha chain gene (FGA), which is closely related to hereditary fibrinogen abnormality, and the mutation site was located in p.R350H. After a follow-up period of 12 mo, the mother and her newborn had a good prognosis without bleeding or thrombosis. CONCLUSION: Pregnant women with CD may have atypical symptoms, which can easily lead to misdiagnosis. In addition, treatment can be attempted according to the principles of acute fatty liver management. This rare pregnant patient with CD was caused by a novel FGA (p.R350H) gene mutation.
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BACKGROUND: Lynch syndrome (LS) is an autosomal dominant hereditary disorder because of germline mutations in DNA mismatch repair genes, such as MutL homolog 1 (MLH1), PMS1 homolog 2, MutS homolog 2, and MutS homolog 6. Gene mutations could make individuals and their families more susceptible to experiencing various malignant tumors. In Chinese, MLH1 germline mutation c.(453+1_454-1)_(545+1_546-1)del-related LS has been infrequently reported. Therefore, we report a rare LS patient with colorectal and endometrioid adenocarcinoma and describe her pedigree characteristics. CASE SUMMARY: A 57-year-old female patient complained of irregular postmenopausal vaginal bleeding for 6 mo. She was diagnosed with LS, colonic malignancy, endometrioid adenocarcinoma, secondary fallopian tube malignancy, and intermyometrial leiomyomas. Then, she was treated by abdominal hysterectomy, bilateral oviduct oophorectomy, and sentinel lymph node resection. Genetic testing was performed using next-generation sequencing technology to detect the causative genetic mutations. Moreover, all her family members were offered a free genetic test, but no one accepted it. CONCLUSION: No tumor relapse or metastasis was found in the patient during the 30-mo follow-up period. The genetic panel sequencing showed a novel pathogenic germline mutation in MLH1, c.(453+1_454-1)_(545+1_546-1)del, for LS. Moreover, cancer genetic counseling and testing are still in the initial development state in China, and maybe face numerous challenges in the further.
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Achieving high exciton utilization is a long-cherished goal in the development of organic light-emitting diode materials. Herein, a three-step mechanism is proposed to achieve 200% exciton utilization: (i) hot triplet exciton (T2) conversion to singlet S1; (ii) singlet fission from S1 into two T1; (iii) and then a Dexter energy transfer to phosphors. The requirement is that S1 should lie slightly lower than or close to T2 and twice as high as T1 in energy. For this, a scenario is put forward to design a series of donor-bridge-acceptor (DBA) type molecules with 2E(T1) ≤ E(S1) < E(T2), in which the Baird-type aromatic pyrazoline ring is used as a bridge owing to its stabilized T1 (1.30-1.74 eV) and different kinds of donors and acceptors are linked to the bridge for regulating S1 (2.35-3.87 eV) and T2 (2.44-3.96 eV). The ultrafast spectroscopy and sensitization measurements for one compound (TPA-DBPrz) fully confirm the theoretical predictions.
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Despite advances in cervical cancer screening and human papilloma virus (HPV) vaccines, cervical cancer remains a global health burden. The standard treatment of cervical cancer includes surgery, radiation therapy, and chemotherapy. Radiotherapy (RT) is the primary treatment for advanced-stage disease. However, due to radioresistance, most patients in the advanced stage have an adverse outcome. Recent studies have shown that long noncoding RNAs (lncRNAs) participate in the regulation of cancer radiosensitivity by regulating DNA damage repair, apoptosis, cancer stem cells (CSCs), and epithelial-mesenchymal transition (EMT). In this review, we summarize the molecular mechanisms of long noncoding RNAs in cervical cancer and radiosensitivity, hoping to provide a theoretical basis and a new molecular target for the cervical cancer RT in the clinic.
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Two new sets of UiO-Zr metal-organic framework (MOF) bearing mixed linkers BDC-(SCH3)2 and BDC-(SOCH3)2 that have different band gaps and edges were prepared through post oxidation and direct methods, namely, UiO-66-(SCH3)2-xh (x = 4, 9, 12 oxidation hours) and UiO-66-(SOCH3)x(SCH3)2-x (x = 0, 0.4, 0.6, 2), respectively. These composites with stoichiometric components were fully characterized via proton nuclear magnetic resonance (1H NMR) spectroscopy, powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectra, Brunauer-Emmett-Teller (BET), photo electrochemical measurements, and femtosecond transient absorption (fs-TA) spectroscopy. The structure, electronic property, and photoresponsive and catalytic ability as the functions of the molar ratio of linkers and the synthetic protocol were first investigated. The mixed-linker UiO-66-(SCH3)2-xh and UiO-66-(SOCH3)x(SCH3)2-x exhibited improved performances as compared to the UiO-66-(SCH3)2 and UiO-66-(SOCH3)2 possessing neat linkers only. Their photo response and catalytic activity varied with different linker ratios. For UiO-66-(SCH3)2-xh, the performance increased with the increasing linker BDC-(SOCH3)2 ratio upon oxidation but reached the highest as the BDC-(SOCH3)2 being of 24.4% in UiO-66-(SCH3)2-9h. In comparison, the best photocurrent (80.74 uA/cm-2) and the highest H2 generation rate (2018.8 µmol g-1 h-1) (λ > 400 nm) in UiO-66-(SCH3)2-9h are about twice those of UiO-66-(SOCH3)0.4(SCH3)1.6 obtained by direct synthesis, although the linker BDC-(SOCH3)2 ratio of those two composites is almost the same (24.4% vs 23.9%). Recorded shorter lifetime and higher charge separation efficiency of the former than those of the latter suggest the postsynthetic protocol as the efficient method for achieving the mixed-liner-MOF-based photocatalyst with high performance. A new type-II tailored homojunction is proposed in these mixed-linker MOFs for their efficient charge separation and improved activity.
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Singlet fission (SF), the conversion of one high-energy singlet to two low-energy triplets, provides the potential to increase the efficiency of photovoltaic devices. In the SF chromophores with C2h symmetry, exemplified by polyenes, singlet-to-triplet conversion generally involves a low-lying 21Ag dark state, which serves as either a multiexciton (ME) intermediate to promote the SF process or a parasitic trap state to shunt excited-state populations via internal conversion. This controversial behavior calls for a deep understanding of dark-state-related photophysics involving the higher-lying singlet state. However, the optical "dark" and "transient" nature of these dark states and strong correlation feature of double exciton species make their characterization and interpretation challenging from both experimental and computational perspectives. In the present work combining transient spectroscopy and multireference electronic structure calculations (XDW-CASPT2), we addressed a new photophysical model, i.e., a high-lying 31Ag dark-state-mediated ultrafast SF process in the benzodipyrrolidone (BDPP) skeleton. Such a 31Ag dark state with distinctive double excitation character, described as the ME state, could be populated from the initial 11Bu bright state on an ultrafast time scale given the quasi-degeneracy and intersection of the two electronic states. Furthermore, the suitable optical band gap and triplet energy, high triplet yield, and excellent photostability render BDPP a promising SF candidate for photovoltaic devices. These results not only enrich the arsenal of SF materials but also shed new insights into the understanding of dark-state-related photophysics, which could promote the development of new SF-active materials.
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Stimulated emission depletion (STED) nanoscopy plays a key role in achieving sub-50 nm high spatial resolution for subcellular live-cell imaging. To avoid re-excitation, the STED wavelength has to be tuned at the red tail of the emission spectrum of fluorescent probes, leading to high depletion laser power that might damage the cell viability and functionality. Herein, with the highly emissive silica-coated core-shell organic nanoparticles (CSONPs) enabling a giant Stokes shift of 150 nm, ultralow power STED is achieved by shifting the STED wavelength to the emission maximum at 660 nm. The stimulated emission cross section is increased by â¼20-fold compared to that at the emission red tail. The measured saturation intensity and lateral resolution of our CSONP are 0.0085 MW cm-2 and 25 nm, respectively. More importantly, long-term (>3 min) dynamic super-resolution imaging of the lysosomal fusion-fission processes in living cells is performed with a resolution of 37 nm.
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Nanopartículas , Corantes Fluorescentes , Lasers , Microscopia de Fluorescência , Dióxido de SilícioRESUMO
Synthetic routes for heteroatom-containing polycyclic aromatic hydrocarbons (H-PAHs) with alkyl and aryl substitution are demonstrated. Three H-PAHs, including heteroatom-containing rubicenes (H-rubicenes), angular-benzothiophenes (ABTs), and indenothiophene (IDTs) were successfully synthesized by two key steps, including polysubstituted olefin formation and cyclization. Specifically, ABT and H-rubicenes were comprehensively investigated by single-crystal X-ray diffraction, NMR spectroscopy, UV-vis absorption, cyclic voltammetry, transient absorption, and single-crystal OFET measurements.
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Large-area 2D cocrystals with strong near-infrared (NIR) absorption have been designed and prepared. Driven by the intermolecular charge-transfer (CT) interactions, zinc tetraphenylporphyrin (donor) and C60 (acceptor) self-assemble into a NIR cocrystal with absorption wavelength up to 1080â nm. By tailoring the growth solvents and processes, the cocrystal morphologies can be tuned from 1D nanowires, 2D nanosheets to large-area 2D cocrystal films with length reaching several millimeters. Owing to the highly ordered donor-acceptor arrangement, the CT absorption in the 2D cocrystals is enhanced and is comparable to singlet absorption. The uniform 2D cocrystals, with enhanced CT absorption in the NIR region, displays a high responsivity of 2424â mA W-1 to NIR light and a fast response time of 0.6â s. The excellent device performance is attributed to the generation of long-lived free charge carriers as revealed by transient absorption spectroscopy and optimization of device configuration.
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Obtaining a large open-circuit voltage (VOC ) and high short-circuit current density (JSC ) simultaneously is important in improving power conversion efficiency (PCE) of organic photovoltaics. The ternary strategy with using a higher lowest unoccupied molecular orbital (LUMO) level nonfullerene acceptor (NFA) guest can achieve increased VOC , yet JSC is decreased or maintained, so it's still a challenge to offer increased VOC and JSC values concurrently via the newly presented VOC -increased ternary strategy. To overcome this issue, a new narrow bandgap NFA TT-S-4F is reported by introducing 3,6-dimethoxylthieno[3,2-b]thiophene (TT) as π-spacers to connect electron-rich core with terminal groups, so as to upshift the LUMO level and extend π-system. When adding 10% TT-S-4F into binary system based on PTB7-Th:IEICO-4F, the higher-LUMO-level of TT-S-4F, the increased charge mobilities, the reduced trap-assisted combination loss, and a finer nanofiber structure and increased phase separation size are obtained, which simultaneously promotes JSC , VOC , and fill factor (FF), thus obtaining an optimal PCE (12.5% vs 11.5%). This work illustrates that an extending conjugated backbone with large π-spacers and inclusion of alkylthiophenyl side-chains is a concept to synthesize NFA guests for use on the VOC -increased ternary strategy that enables to realize simultaneously increased JSC , VOC , and FF.
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Nanofibras , Energia Solar , Fontes de Energia Elétrica , Polímeros , TiofenosRESUMO
The exploitation of singlet fission (SF) in photovoltaic devices is restricted by the limited number of SF materials available and the conflicting requirement of intermolecular interactions to satisfy both efficient SF and subsequent triplet extraction. Intramolecular SF (iSF) represents an emerging alternative and may prove simpler to implement in devices. On account of the excellent chemical structure tunability and solution processability, conjugated polymers have emerged as promising candidates for iSF materials despite being largely underexplored. It remains a significant challenge to develop SF-capable conjugated polymers and achieve efficient dissociation of the formed triplet pairs simultaneously. In this contribution, we present a new iSF material in a para-azaquinodimethane-based quinoidal conjugated polymer. Using transient optical techniques, we show that an ultrafast iSF process dominates the deactivation of the excited state in such polymer, featuring ultrafast population (<1 ps) and stepwise dissociation of triplet pairs. Notably, these multiexciton states could further diffuse apart to produce long-lived free triplets (tens of µs) in strongly coupled aggregates in solid thin film. Such findings not only introduce a new iSF-active conjugated polymer to the rare SF material family but also shed unique insight into interchain interaction-promoted triplet pair dissociation in aggregates of conjugated polymers, thus openning new avenues for developing next-generation SF-based photovoltaic materials.
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Organic room-temperature phosphorescence (ORTP) has been demonstrated successfully in solids. In contrast, solution-phase ORTP is rarely achieved, because the T1 â S0 phosphorescence is too slow to compete against nonradiative decay and the oxygen-quenching effect. Here, we reported that suppression of Kasha's rule is a strategy to achieve solution-phase ORTP from the high-lying T2 state by spatially separating T2 and T1 on different parts of the molecule (CzCbDBT) composed of carbonyl (Cb), dibenzothiophene (DBT), and carbazole moiety (Cz). On one hand, intersystem crossing (ISC) is much faster from S1 to T2 than that to T1, owing to the small energy-gap ΔES1-T2 and large spin-orbital coupling ξS1-T2. On the other hand, T2 â T1 internal conversion is inhibited owing to spatial separation, i.e., T2 on CbDBT and T1 on Cz, respectively. Also, combination of very fast radiative decay from T2 to S0 owing to large ξT2-S0, the efficient solution-phase ORTP emission from the T2 state was finally achieved.
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Singlet fission (SF) materials hold the potential to increase the power conversion efficiency of solar cells by reducing the thermalization of high-energy excited states. The major hurdle in realizing this potential is the limited scope of SF-active materials with high fission efficiency, suitable energy levels, and sufficient chemical stability. Herein, using theoretical calculation and time-resolved spectroscopy, we developed a highly stable SF material based on dipyrrolonaphthyridinedione (DPND), a pyrrole-fused cross-conjugated skeleton with a distinctive adaptive aromaticity (dual aromaticity) character. The embedded pyrrole ring with 4n+2 π-electron features aromaticity in the ground state, while the dipole resonance of the amide bonds promotes a 4n π-electron Baird's aromaticity in the triplet state. Such an adaptive aromaticity renders the molecule efficient for the SF process [E(S1) ≥ 2E(T1)] without compromising its stability. Up to 173% triplet yield, strong blue-green light absorption, and suitable triplet energy of 1.2 eV, as well as excellent stability, make DPND a promising SF sensitizer toward practical applications.
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Exosomes are endosome-derived extracellular vesicles that are released upon the fusion of multivesicular bodies with the plasma membrane. These vesicles contain proteins, lipids, and nucleic acids and are found in various human body fluids. Exosomes can transfer bioactive molecules to nearby or distant recipient cells, thereby affecting their function. Recently, exosomes have gained importance as a medium of communication between tumor cells. An increasing number of studies have found that non-coding RNAs in tumor cell-derived exosomes can regulate tumor microenvironments, inhibit immune cell function, promote the growth and invasion of tumor cells, and impart resistance to chemicals in tumor cells. In this review, we focus on the effects of exosomal long non-coding RNAs (lncRNAs) on tumors. As exosomes and their parent cells have similar biological characteristics and coated lncRNAs can exist stably in vivo without being degraded by RNases, exosomal lncRNAs have emerged as novel non-invasive tumor biomarkers for use in the early diagnosis and evaluation of prognosis of tumors. Advancements in the field have led to the development of a variety of techniques in exosomal non-coding RNA research. Currently, most methods include the separation and purification of exosomes, followed by RNA extraction, reverse transcription, and subsequent analyses; thus, these processes are very tedious and vulnerable to contamination and could lead to inaccurate and inconsistent results. Thus, there has been an increase in the development of detection methods for exosomal RNAs. Here, we discuss the existing research methods, their advantages and disadvantages, and a few new techniques.
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Exossomos/metabolismo , Neoplasias/metabolismo , RNA Longo não Codificante/metabolismo , Microambiente Tumoral/fisiologia , Antineoplásicos/uso terapêutico , Exossomos/genética , Humanos , RNA Longo não Codificante/genética , Projetos de PesquisaRESUMO
Singlet fission (SF) holds the potential to boost the maximum power conversion efficiency of photovoltaic devices. Internal conversion (IC) has been considered as one of the major competitive deactivation pathways to transform excitation energy into heat. Now, using time-resolved spectroscopy and theoretical calculation, it is demonstrated that, instead of a conventional IC pathway, an unexpected intramolecular singlet fission (iSF) process is responsible for excited state deactivation in isoindigo derivatives. The 1 TT state could form at ultrafast rate and nearly quantitatively in solution. In solid films, the slipped stacked intermolecular packing of a thiophene-functionalized derivative leads to efficient triplet pair separation, giving rise to an overall triplet yield of 181 %. This work not only enriches the pool of iSF-capable materials, but also contributes to a better understanding of the iSF mechanism, which could be relevant for designing new SF sensitizers.