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The world population is rapidly aging. Societal aging poses many challenges for individuals, families, nations, and the global healthcare system. Therefore, geriatric care is a crucial issue that demands our attention. In this case report, we describe a woman in her early 70s with multiple comorbidities, polypharmacy, and renal insufficiency who developed cefepime-induced encephalopathy with moderate to severe cerebral dysfunction during treatment of a urinary tract infection. The patient's consciousness level gradually improved, and no further seizures were observed following the discontinuation of cefepime for several days. This case report underscores the fact that polypharmacy and medication safety are significant concerns that are often overlooked when caring for older patients. The report also highlights the increased susceptibility of older individuals to antibiotic-associated adverse reactions during the management of infectious diseases. Therefore, optimization of antibiotic therapy for older patients is a critical issue that requires thorough investigation and consideration in geriatric care.
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Antibacterianos , Encefalopatías , Cefepima , Polifarmacia , Insuficiencia Renal , Infecciones Urinarias , Humanos , Cefepima/efectos adversos , Cefepima/uso terapéutico , Femenino , Anciano , Encefalopatías/inducido químicamente , Infecciones Urinarias/tratamiento farmacológico , Insuficiencia Renal/inducido químicamente , Antibacterianos/efectos adversos , Antibacterianos/uso terapéuticoRESUMEN
To meet the demand for quillaic acid, a multigram synthesis of quillaic acid was accomplished in 14 steps, starting from oleanolic acid, leading to an overall yield of 3.4%. Key features include C-H activation at C-16 and C-23. Through Pd-catalyzed C-H acetoxylation, the oxidation at C-23 was observed as the major product, as opposed to at C-24. A copper-mediated C-H hydroxylation using O2 successfully afforded the single isomer, 16ß-ol triterpenoid, followed by configuration inversion to the desired 16α-ol compound. In summary, with steps optimized and conducted on a multigram scale, quillaic acid could be feasibly acquired through C-H activation with inexpensive copper catalysts, promoting a more sustainable approach.
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Anthropogenic shifts in seas are reshaping fishing trends, with significant implications for aquatic food sources throughout this century. Examining a 21-year abundance dataset of Argentine shortfin squids Illex argentinus paired with a regional oceanic analysis, we noted strong correlations between squid annual abundance and sea surface temperature (SST) in January and February and eddy kinetic energy (EKE) from March to May in the Southwest Atlantic. A deeper analysis revealed combined ocean-atmosphere interactions, pinpointed as the primary mode in a rotated empirical orthogonal function analysis of SST. This pattern produced colder SST and amplified EKE in the surrounding seas, factors crucial for the unique life stages of squids. Future projections from the CMIP6 archive indicated that this ocean-atmosphere pattern, referred to as the Atlantic symmetric pattern, would persist in its cold SST phase, promoting increased squid abundance. However, rising SSTs due to global warming might counteract the abundance gains. Our findings uncover a previously unrecognized link between squids and specific environmental conditions governed by broader ocean-atmosphere interactions in the Southwest Atlantic. Integrating these insights with seasonal and decadal projections can offer invaluable information to stakeholders in squid fisheries and marine conservation under a changing climate.
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Atmósfera , Decapodiformes , Decapodiformes/fisiología , Animales , Océano Atlántico , Temperatura , Estaciones del Año , Cambio ClimáticoRESUMEN
Plasmonic Cu@semiconductor heteronanocrystals (HNCs) have many favorable properties, but the synthesis of solid structures is often hindered by the nanoscale Kirkendall effect. Herein, we present the use of an atomically thin Au3Cu palisade interlayer to reduce lattice mismatch and mediate the Kirkendall effect, enabling the successive topological synthesis of Cu@Au3Cu@Ag, Cu@Au3Cu@Ag2S, and further transformed solid Cu@Au3Cu@CdS core-shell HNCs via cation exchange. The atomically thin and intact Au3Cu palisade interlayer effectively modulates the diffusion kinetics of Cu atoms as demonstrated by experimental and theoretical investigations and simultaneously alleviates the lattice mismatch between Cu and Ag as well as Cu and CdS. The Cu@Au3Cu@CdS HNCs feature exceptional crystallinity and atomically organized heterointerfaces between the plasmonic metal and the semiconductor. This results in the efficient plasmon-induced injection of hot electrons from Cu@Au3Cu into the CdS shell, enabling the Cu@Au3Cu@CdS HNCs to achieve high activity and selectivity for the photocatalytic reduction of CO2 to CO.
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Tailoring nanoparticles' composition and morphology is of particular interest for improving their performance for catalysis. A challenge of this approach is that the nanoparticles' optimized initial structure often changes during use. Visualizing the three dimensional (3D) structural transformation in situ is therefore critical, but often prohibitively difficult experimentally. Although electron tomography provides opportunities for 3D imaging, restrictions in the tilt range of in situ holders together with electron dose considerations limit the possibilities for in situ electron tomography studies. Here, an in situ 3D imaging methodology is presented using single particle reconstruction (SPR) that allows 3D reconstruction of nanoparticles with controlled electron dose and without tilting the microscope stage. This in situ SPR methodology is employed to investigate the restructuring and elemental redistribution within a population of PtNi nanoparticles at elevated temperatures. The atomic structure of PtNi is further examined and a heat-induced transition is found from a disordered to an ordered phase. Changes in structure and elemental distribution are linked to a loss of catalytic activity in the oxygen reduction reaction. The in situ SPR methodology employed here can be extended to a wide range of in situ studies employing not only heating, but gaseous, aqueous, or electrochemical environments to reveal in-operando nanoparticle evolution in 3D.
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3-O-ß-Glucuronide triterpenes are plant-derived compounds. Some of them have been used as herbal medicine and in pharmaceuticals, such as chikusetsu saponins and Quillaja saponins. However, the demand for these materials has remained largely a challenge owing to their natural scarcity and low-yielding purification process. Therefore, a chemical triterpene 3-O-glucuronidation was conducted in this study to alleviate the surging demand on natural source. Various glucuronyl imidate donors and oleanane-type triterpene acceptors were synthesized, and the relative reactivity values (RRV) and acceptor nucleophilic constants (Aka) were systematically measured to study their influence on glucuronidation yield. As a result, applying donors in higher RRV value generally improved the production of 3-O-glucuronide triterpenes. Meanwhile, a bulky pivaloyl group was an ideal 2-O-protection to provide ß-selectivity and prevented side reactions, including orthoester formation and acyl-transfer reaction. Collectively, a positive correlation was observed between reactive donors/acceptors and improved glucuronidation yields. These findings offered insights on the influence of donors' and acceptors' reactivities on 3-O-ß-glucuronide triterpenes synthesis, and this knowledge would help to access saponins of interest to address future needs.
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Plantas Medicinales , Saponinas , Triterpenos , Triterpenos/química , Glucurónidos , Plantas Medicinales/química , Saponinas/química , Extractos Vegetales/químicaRESUMEN
People with dementia (PwD) who receive home healthcare (HHC) may have distressing symptoms, complex care needs and high mortality rates. However, there are few studies investigating the determinants of mortality in HHC recipients. To identify end-of-life care needs and tailor individualized care goals, we aim to explore the mortality rate and its determinants among PwD receiving HHC. We conducted a retrospective cohort study using a Taiwanese national population database. People with new dementia diagnosis in 2007-2016 who received HHC were included. We calculated the accumulative mortality rate and applied Poisson regression model to estimate the risk of mortality for each variable (adjusted risk ratios, aRR) with a 95% confidence interval (CI). We included 95,831 PwD and 57,036 (59.5%) of them died during the follow-up period (30.5% died in the first-year). Among comorbidities, cirrhosis was associated with the highest mortality risks (aRR 1.65, 95% CI 1.49-1.83). Among HHC-related factors, higher visit frequency of HHC (> 2 versus â¦1 times/month, aRR 3.52, 95% CI 3.39-3.66) and higher level of resource utilization group (RUG, RUG 4 versus 1, aRR = 1.38, 95% CI 1.25-1.51) were risk factor of mortality risk. Meanwhile, HHC provided by physician and nurse was related to reduced mortality risk (aRR 0.79, 95% CI 0.77-0.81) compared to those provided by nurse only. Anticipatory care planning and timely end-of life care should be integrated in light of the high mortality rate among PwD receiving HHC. Determinants associated with increased mortality risk facilitate the identification of high risk group and tailoring the appropriate care goals. Trial registration number: ClinicalTrials.gov Identifier is NCT04250103 which has been registered on 31st January 2020.
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Demencia , Servicios de Atención de Salud a Domicilio , Humanos , Estudios de Cohortes , Estudios Retrospectivos , Atención a la Salud , Demencia/epidemiologíaRESUMEN
Tunable devices constructed by ferroelectric thin films are often desired to possess a low dielectric loss while maintainging a high dielectric tunability over a broad operating temperature range in applications, for example, resonators, filters, or phase shifters. However, it is difficult to simultaneously achieve these characteristics by traditional strategies, such as doping and strain modifying. Here, we demonstrate that the dielectric tunability of the sol-gel-prepared Pb(Sc1/2Nb1/2)0.9(Mg1/3Nb2/3)0.1O3 (PSNMN) thin film can be almost doubled from ~47% to ~80.0% (at 10 kHz) at a low electric field (~530 kV/cm), and the dielectric loss can be sharply reduced by more than an order of magnitude, from ~0.50 to ~0.037 (at 1 kHz) when the thin film was annealed in air at 650°C for 15 h under the help of an atmosphere-compensating-block (ACB) made from the proto-PSNMN gel. Moreover, the PSNMN thin film annealed with ACB also exhibited an extremely high thermally-stable dielectric tunability in an ultrabroad temperature range (>130 K), which could be attributed to the Maxwell-Wagner (MW) effect generated by the interface between the PSNMN disordered matrix and the B-site nanoscale-ordered structure formed during the long-term annealing process. The reduced dielectric loss is mainly benefited from the reduced concentration of oxygen vacancy and the possible MW effects, and the enhanced dielectric tunability could be ascribed to the weaker domain-pinning effect by oxygen vacancy. The breakthrough provides a new universal strategy to achieve utrahigh tunable performance in A(B'1/2B"1/2)O3 ferroelectric thin films with a B-site nanoscale-ordered structure, meanwhile it paves the way for ultraintergrated tunable thin-film-devices with great phase shifter performance in practical applications.
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Silicon carbide (SiC), one of the third-generation semiconductor materials with excellent electrical and optoelectronic properties, is ideal for high light-sensing performance. Here, a self-powered SiC ultraviolet (UV) photodetector (PD) is constructed with wider applicability and higher commercialization potential. The great performance of the PD is realized by a remarkable photoinduced dynamic Schottky effect derived from the symbiotic modulation of Schottky and Ohmic contact. Using the pyro-phototronic effect that exists in the N-doped 4H-SiC single crystal PDs, a fast pyroelectric response time of 0.27 s is achieved, which is almost ten times shorter than that obtained from the steady-state signal under UV illumination. The maximal transient photoresponsivity reaches 9.12 nA mW-1 , which is ≈20% higher than the conventional photoelectric signal. Moreover, different regions of the 4H-SiC centimeter-scale chip output distinct signals under UV illumination, demonstrating efficient optical imaging and information transmission capabilities of this device. This work not only reveals the fundamental optoelectronic physics lying in this vital third-generation semiconductor, but also sheds light on its potential photosensing applications for large-scale commercialization.
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Scanning transmission electron microscopy (STEM) tomography is widely used to reveal three-dimensional (3D) structure of the specimens from nanometers to atomic resolution. Advances in transmission electron microscope enable high resolution and low dose data acquisition for 3D reconstruction to resolve 3D coordinates of single atoms. Meanwhile, the developments of reconstruction algorithms increase the reconstruction quality. However, the as-acquired raw datasets often require alignments before they can be used as inputs to feed a reconstruction algorithm. The effect of post-acquisition data misalignments on the final reconstruction quality of STEM tomography is less discussed. Here, using phantom datasets with a focus on atomic features, we simulate a range of misalignments on each alignment step and correlate the level of misalignments to the final reconstruction quality. The study pinpoints that accurate alignments of tilt angles and stack positions and minimizing scan distortion are important to the reconstruction quality, while the sequence of alignment steps do not affect the reconstruction quality. The study not only emphasizes the most important alignment steps that should be pay attention to for a high-quality 3D reconstruction, but also summarizes post-acquisition data alignment procedures as a primer for new practitioners to use STEM tomography.
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Tomografía con Microscopio Electrónico , Procesamiento de Imagen Asistido por Computador , Algoritmos , Tomografía con Microscopio Electrónico/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Fantasmas de ImagenRESUMEN
Engineering the structure of core-shell colloidal semiconductor nanoparticles (CSNPs) is attractive due to the potential to enhance photo-induced charge transfer and induce favorable optical and electronic properties. Nonetheless, the sensitivity of telluride CSNPs to high temperatures makes it challenging to precisely modulate their surface crystallinity. Herein, we have developed an efficient strategy for synthesizing telluride CSNPs with thin amorphous shells using aqueous cation exchange (ACE). By changing the synthesis temperature in the range of 40-110 °C, the crystallinity of the CdTe nanoparticles was controllable from perfect crystals with no detectable amorphous shell (c-CdTe) to a core-shell structure with a crystalline CdTe NP core covered by an amorphous shell of tunable thickness up to 7-8 nm (c@a-CdTe). A second ACE step transformed c@a-CdTe to crystalline CdTe@HgTe core-shell NPs. The c@a-CdTe nanoparticles synthesized at 60 °C and having a 4-5 nm thick amorphous shell exhibited the highest surface-enhanced Raman scattering activity with a high enhancement factor around 8.82 × 105, attributed to the coupling between the amorphous shell and the crystalline core.
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The physical properties of clays and micas can be controlled by exchanging ions in the crystal lattice. Atomically thin materials can have superior properties in a range of membrane applications, yet the ion-exchange process itself remains largely unexplored in few-layer crystals. Here we use atomic-resolution scanning transmission electron microscopy to study the dynamics of ion exchange and reveal individual ion binding sites in atomically thin and artificially restacked clays and micas. We find that the ion diffusion coefficient for the interlayer space of atomically thin samples is up to 104 times larger than in bulk crystals and approaches its value in free water. Samples where no bulk exchange is expected display fast exchange at restacked interfaces, where the exchanged ions arrange in islands with dimensions controlled by the moiré superlattice dimensions. We attribute the fast ion diffusion to enhanced interlayer expandability resulting from weaker interlayer binding forces in both atomically thin and restacked materials. This work provides atomic scale insights into ion diffusion in highly confined spaces and suggests strategies to design exfoliated clay membranes with enhanced performance.
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BACKGROUND: People with dementia are a high-risk group for hip fractures. Although the increased risk of hip fractures associated with antipsychotic drugs (APD) is found in older populations, little is known about the risk for people with dementia living in Asia. We aimed to investigate the association between hip fractures and the characteristics of APD use in patients with dementia. METHODS: A nested case-control analysis was conducted on a nationwide cohort in Taiwan. People with diagnoses of dementia during 2003-2012 were identified. Conditional logistic regression analysis was performed, and adjusted odds ratios (aORs) were calculated with a 95% confidence interval (CI) to estimate the risk of hip fractures. RESULTS: APD use was associated with an increased risk of hip fractures in patients with dementia; current use or combined use of first and second generations of APDs had even higher risks. Regarding the duration of APD use, a U-shape curve of hip fracture risk was noted, and the risk peaked during 0-15 days and >215 days of exposure (aOR = 1.46, 95% CI 1.37-1.57; aOR = 1.47, 95% CI 1.37-1.58; respectively). Considering the doses of APDs, the hip fracture risk was significantly increased with all four levels of the cumulative doses and average daily doses and peaked in the group with the highest average daily dose. CONCLUSIONS: The findings suggest that caution must be taken when initiating APD use in patients with dementia, even in a small dose, and mixed types of APD prescriptions should be administered with care. Furthermore, frequent evaluation of the possibility of tapering or withdrawal of the medication is necessary, as the risk does not attenuate after long-term use.
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Demencia , Fracturas de Cadera , Preparaciones Farmacéuticas , Anciano , Estudios de Casos y Controles , Demencia/inducido químicamente , Demencia/epidemiología , Fracturas de Cadera/inducido químicamente , Fracturas de Cadera/epidemiología , Humanos , Factores de RiesgoRESUMEN
We report a rapid solution-phase strategy to synthesize alloyed PtNi nanoparticles which demonstrate outstanding functionality for the oxygen reduction reaction (ORR). This one-pot coreduction colloidal synthesis results in a monodisperse population of single-crystal nanoparticles of rhombic dodecahedral morphology with Pt-enriched edges and compositions close to Pt1Ni2. We use nanoscale 3D compositional analysis to reveal for the first time that oleylamine (OAm)-aging of the rhombic dodecahedral Pt1Ni2 particles results in Ni leaching from surface facets, producing aged particles with concave faceting, an exceptionally high surface area, and a composition of Pt2Ni1. We show that the modified atomic nanostructures catalytically outperform the original PtNi rhombic dodecahedral particles by more than two-fold and also yield improved cycling durability. Their functionality for the ORR far exceeds commercially available Pt/C nanoparticle electrocatalysts, both in terms of mass-specific activities (up to a 25-fold increase) and intrinsic area-specific activities (up to a 27-fold increase).
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Single-particle reconstruction can be used to perform three-dimensional (3D) imaging of homogeneous populations of nano-sized objects, in particular viruses and proteins. Here, it is demonstrated that it can also be used to obtain 3D reconstructions of heterogeneous populations of inorganic nanoparticles. An automated acquisition scheme in a scanning transmission electron microscope is used to collect images of thousands of nanoparticles. Particle images are subsequently semi-automatically clustered in terms of their properties and separate 3D reconstructions are performed from selected particle image clusters. The result is a 3D dataset that is representative of the full population. The study demonstrates a methodology that allows 3D imaging and analysis of inorganic nanoparticles in a fully automated manner that is truly representative of large particle populations.
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Piezo-phototronic effect is a fundamental effect of semiconductors lacking of central symmetry with geometries from one-dimensional (1D) nanowire to 3D bulk. Here, we present that the piezo-phototronic effect can even tune a spin-orbit coupled photoluminescence (PL) based on all-inorganic perovskite CsPbBr3 quantum dots (QDs). Although the cubic structure of CsPbBr3 QDs is nonpiezoelectric, a cooling treatment can change it to an orthorhombic structure, which is proven to possess a piezoelectric property. The spin-orbit coupled PL intensity is demonstrated to be dependent on the polarization of the excited light. Because of the manipulation of the spin-split energy levels via the piezo-phototronic effect, the spin-orbit coupled PL intensities under a -0.9% compressive strain for linearly and circularly polarized light excitations can be enhanced by 136% and 146%, respectively. These findings reveal fundamental understandings of the spin-orbit coupled PL dynamics and demonstrate promising optoelectronic applications of the piezo-phototronic effect in these QDs.
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Metal sulfide and metal oxide alloys of the form Mo1-x W x S2 and Mo1-x W x O3 (0 ≤ x ≤ 1) are synthesized with varying nominal stoichiometries (x = 0, 0.25, 0.50, 0.75, and 1.0) by thermolysis of the molecular precursors MoL4 and WS(S2)L2 (where L = S2CNEt2) in tandem and in various ratios. Either transition-metal dichalcogenides or transition-metal oxides can be produced from the same pair of precursors by the choice of reaction conditions; metal sulfide alloys of the form Mo1-x W x S2 are produced in an argon atmosphere, while the corresponding metal oxide alloys Mo1-x W x O3 are produced in air, both under atmospheric pressure at 450 °C and for only 1 h. Changes in Raman spectra and in powder X-ray diffraction patterns are observed across the series of alloys, which confirm that alloying is successful in the bulk materials. For the oxide materials, we show that the relatively complicated diffraction patterns are a result of differences in the tilt angle of MO6 octahedra within three closely related unit cell types. Alloying of Mo and W in the products is characterized at the microscale and nanoscale by scanning electron microscopy-energy-dispersive X-ray spectroscopy (EDX) and scanning transmission electron microscopy-EDX spectroscopy, respectively.
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AIMS: We evaluated the association between type 2 diabetes and gout by a retrospective cohort study. METHODS: Data of 17,259 male and 18,318 female patients with type 2 diabetes were retrieved for the 1998-2010 period. These patients were matched to a comparison group (n=34,518 and n=36,636, respectively) in a 1:2 ratio by age and region. RESULTS: We found that patients with type 2 diabetes after adjustment for hyperlipidemia and hypertension had a lower risk of incident gout than the matched population (incidence rate ratio, men: 0.39 [95% CI: 0.36-0.42]; women: 0.78 [0.72-0.84]). Specifically, type 2 diabetes alone without hyperlipidemia and hypertension was associated with a reduced risk of incident gout in men (adjusted relative risk [RR]: 0.29, 95% CI: 0.22-0.39), but not in women (0.86, 95% CI: 0.55-1.36). We found that insulin users with hyperlipidemia and hypertension associated with risk of incident gout and no sex-specific differences were noted (adjusted RR, men: 1.28 [95% CI: 1.11-1.48]; women: 1.32 [95% CI: 1.14-1.53]). Specifically, insulin users alone without hyperlipidemia and hypertension were not statistically significantly associated with gout risk (P≥.0954). CONCLUSIONS: The results of this study indicated that hyperlipidemia and hypertension modified the association between type 2 diabetes and gout.
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Diabetes Mellitus Tipo 2 , Gota , Hiperlipidemias , Hipertensión , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiología , Femenino , Gota/diagnóstico , Gota/epidemiología , Humanos , Hiperlipidemias/diagnóstico , Hiperlipidemias/epidemiología , Hipertensión/diagnóstico , Hipertensión/epidemiología , Incidencia , Masculino , Estudios Retrospectivos , Factores de RiesgoRESUMEN
We develop herein plasmonic-catalytic Au-IrO2 nanostructures with a morphology optimized for efficient light harvesting and catalytic surface area; the nanoparticles have a nanoflower morphology, with closely spaced Au branches all partially covered by an ultrathin (1 nm) IrO2 shell. This nanoparticle architecture optimizes optical features due to the interactions of closely spaced plasmonic branches forming electromagnetic hot spots, and the ultra-thin IrO2 layer maximizes efficient use of this expensive catalyst. This concept was evaluated towards the enhancement of the electrocatalytic performances towards the oxygen evolution reaction (OER) as a model transformation. The OER can play a central role in meeting future energy demands but the performance of conventional electrocatalysts in this reaction is limited by the sluggish OER kinetics. We demonstrate an improvement of the OER performance for one of the most active OER catalysts, IrO2, by harvesting plasmonic effects from visible light illumination in multimetallic nanoparticles. We find that the OER activity for the Au-IrO2 nanoflowers can be improved under LSPR excitation, matching best properties reported in the literature. Our simulations and electrocatalytic data demonstrate that the enhancement in OER activities can be attributed to an electronic interaction between Au and IrO2 and to the activation of Ir-O bonds by LSPR excited hot holes, leading to a change in the reaction mechanism (rate-determinant step) under visible light illumination.