Reciprocal adaptation of rice and Xanthomonas oryzae pv. oryzae: cross-species 2D GWAS reveals the underlying genetics.

A 1D/2D genome-wide association study strategy was adopted to investigate the genetic systems underlying the reciprocal adaptation of rice (Oryza sativa) and its bacterial pathogen, Xanthomonas oryzae pv. oryzae (Xoo) using the whole-genome sequencing and large-scale phenotyping data of 701 rice accessions and 23 diverse Xoo strains. Forty-seven Xoo virulence-related genes and 318 rice quantitative resistance genes (QR-genes) mainly located in 41 genomic regions, and genome-wide interactions between the detected virulence-related genes and QR genes were identified, including well-known resistance genes/virulence genes plus many previously uncharacterized ones. The relationship between rice and Xoo was characterized by strong differentiation among Xoo races corresponding to the subspecific differentiation of rice, by strong shifts toward increased resistance/virulence of rice/Xoo populations and by rich genetic diversity at the detected rice QR-genes and Xoo virulence genes, and by genome-wide interactions between many rice QR-genes and Xoo virulence genes in a multiple-to-multiple manner, presumably resulting either from direct protein-protein interactions or from genetic epistasis. The observed complex genetic interaction system between rice and Xoo likely exists in other crop-pathogen systems that would maintain high levels of diversity at their QR-loci/virulence-loci, resulting in dynamic coevolutionary consequences during their reciprocal adaptation.

Genome-Wide Association Study Identifies Resistance Loci for Bacterial Blight in a Collection of Asian Temperate Japonica Rice Germplasm.

Growing resistant rice cultivars is the most effective strategy to control bacterial blight (BB), a devastating disease caused by Xanthomonas oryzae pv. oryzae (Xoo). Screening resistant germplasm and identifying resistance (R) genes are prerequisites for breeding resistant rice cultivars. We conducted a genome-wide association study (GWAS) to detect quantitative trait loci (QTL) associated with BB resistance using 359 East Asian temperate Japonica accessions inoculated with two Chinese Xoo strains (KS6-6 and GV) and one Philippine Xoo strain (PXO99A). Based on the 55K SNPs Array dataset of the 359 Japonica accessions, eight QTL were identified on rice chromosomes 1, 2, 4, 10, and 11. Four of the QTL coincided with previously reported QTL, and four were novel loci. Six R genes were localized in the qBBV-11.1, qBBV-11.2, and qBBV-11.3 loci on chromosome 11 in this Japonica collection. Haplotype analysis revealed candidate genes associated with BB resistance in each QTL. Notably, LOC_Os11g47290 in qBBV-11.3, encoding a leucine-rich repeat receptor-like kinase, was a candidate gene associated with resistance to the virulent strain GV. Knockout mutants of Nipponbare with the susceptible haplotype of LOC_Os11g47290 exhibited significantly improved BB resistance. These results will be useful for cloning BB resistance genes and breeding resistant rice cultivars.

Evaluation of open reduction of distal humerus fractures in children after implementation of an enhanced recovery after surgery program.

OBJECTIVE: This study assessed whether an enhanced recovery after surgery (ERAS) protocol could be beneficial for children with distal humerus fractures. METHODS: Children with distal humerus fractures (n = 85) were randomly assigned to the ERAS and control groups and subjected to different perioperative managements. This was followed by the evaluation of their intraoperative characteristics (operation time and bleeding), postoperative characteristics (food intake conditions, pain scores, and discharge time), and postoperative functions. RESULTS: The operation time, intraoperative bleeding, and postoperative hematological indices did not differ significantly between the two groups. Preoperative thirst and hunger were considerably less and the initial food intake duration following surgery was markedly shorter in the ERAS group than in the control group, whereas no difference between the groups was observed in the incidences of postoperative nausea and vomiting. A markedly reduced highest postoperative pain score and reduced mean pain score and demand for additional analgesic interventions were observed in the ERAS group compared with those in the control group, although the differences were not statistically significant. No noticeable between-group differences were observed in the incidences of postoperative incision problems, aspirational pneumonia, and gastroesophageal reflux. The total length of hospital stay was not significantly different between the two groups. However, the length of postoperative hospital stay was remarkably shorter and the elbow joint function at 2 months after surgery was significantly improved in the ERAS group compared with those in the control group. CONCLUSION: The ERAS protocol can ameliorate preoperative discomfort and postoperative pain, shorten the postoperative hospital stay, and accelerate postoperative functional recovery without increasing the risks of postoperative nausea, vomiting, and poor incision healing and is, therefore, worthy of clinical application.

Risk factors of developmental dysplasia of the hip in infants: A meta-analysis based on cohort studies.

INTRODUCTION: Developmental dysplasia of the hip (DDH) is a prevalent condition in children. Currently, the exact etiology of DDH remains uncertain. The objective of this study was to conduct a meta-analysis to investigate the risk factors associated with DDH in infants. The findings would provide a theoretical foundation for targeted early screening and diagnosis. HYPOTHESIS: Several indicators, such as gender, intrauterine position, family history of DDH, gestational age, delivery mode, amniotic fluid levels, swaddling, parity, fetus number, combined musculoskeletal deformities, birth weight, and physical examination results, may serve as risk factors for DDH. MATERIALS AND METHODS: Cohort studies investigating the risk factors of DDH in infants through logistic regression analysis were searched in the Wanfang, VIP citation, China National Knowledge Infrastructure (CNKI), China Biology Medicine disc, Excerpta Medica Database (Embase), PubMed, and Cochrane Library databases up to May 2023. After extracting the data from eligible literature and assessing them using the Newcastle-Ottawa Scale (NOS), articles were selected based on pre-established inclusion and exclusion criteria. RESULTS: A total of eleven literature reports covering 979,757 infants were included in this meta-analysis. The publication bias did not significantly influence the results. The incidence rate of DDH was 47.99‰ among infants with risk factors compared to 3.21‰ in the general population. Risk factors for DDH included being female (OR=6.97, 95% CI: 5.18-9.39, p<0.001), breech delivery (OR=4.14, 95% CI: 3.09-5.54, p<0.001), positive family history (OR=4.07, 95% CI: 2.20-7.52, p<0.001), cesarean section (OR=1.11, 95% CI: 1.01-1.21, p=0.032), oligohydramnios (OR=3.93, 95% CI: 1.29-12.01, p=0.016), swaddling (OR=6.74, 95% CI: 1.25-36.31, p=0.026), firstborn status (OR=1.84, 95% CI: 1.49-2.53, p<0.001), combined musculoskeletal malformations (OR=2.27, 95% CI: 1.58-3.27, p<0.001), and physical signs of DDH (OR=8.71, 95% CI: 2.44-31.07, p=0.001). Premature delivery (OR=0.91, 95% CI: 0.88-0.95, p<0.001) was a protective factor for DDH. The relationship between multiple pregnancies (OR=0.58, 95% CI: 0.33-1.02, p=0.060) and low birth weight (OR=0.62, 95% CI: 0.14-2.76, p=0.529) in relation to DDH remained uncertain. DISCUSSION: This meta-analysis shows that female, breech delivery, positive family history, cesarean section, firstborn status, oligohydramnios, swaddling and combined musculoskeletal malformations are associated with DDH. Premature delivery appeared to be a protective factor against DDH. Nevertheless, the other factors need more research to reach more conclusive results. LEVEL OF EVIDENCE: III; meta-analysis.

Successful use of Palbociclib combined with Venetoclax and Azacitidine in an adult with refractory/relapsed therapy-related acute myeloid leukemia.

BACKGROUND: Therapy-related acute myeloid leukemia (t-AML) is considered high risk as it related to prior exposure to cytotoxic chemotherapy agents for solid tumors or hematologic malignancies. Compared with de novo AML, t-AML is associated with lower remission rates, inferior overall survival (OS) and higher relapse rates. Many efforts have been devoted to improving the overall but with limited success, and novel strategy is thus highly needed. CASE DESCRIPTION: We reported one patient with refractory/relapsed t-AML was successfully treated with Palbociclib combined with Venetoclax and Azacytidine (AZA). In this case, a 47-year-old patient with t-AML recurred during Venetoclax in combination with AZA therapy. However, the patient achieved morphological, immunophenotypic and molecular complete remission again after Palbociclib combined with Venetoclax and AZA. CONCLUSIONS: Although only one successful case is presented here, three-drug combination regimens should be considered as another treatment option for t-AML in the future.

Submuscular plating vs. elastic stable intramedullary nailing for diaphyseal femur fractures in children: a systematic review and meta-analysis.

Objectives: This review evaluates the safety and efficacy of submuscular plating (SMP) vs. elastic stable intramedullary nailing (ESIN) in the treatment of pediatric femur shaft fracture. Method: Studies comparing the efficacy and safety of SMP and ESIN in pediatric shaft fracture were retrieved from five databases (PubMed, Embase, Cochrane, OVID, and Web of Science) from inception to March 2023 using a systematic literature search strategy. A total of 13 outcome measures, such as perioperative parameters, clinical outcomes, and radiographic results, were included in the meta-analysis. Results: Eight eligible studies involving 491 patients were included in the narrative synthesis. There were no significant differences in baseline characteristics between the two groups. Meta-analysis showed reduced radiation time (RT), soft tissue irritation and angular deformation in the SMP group than in the ESIN group. However, the SMP group had greater estimated blood loss (EBL) than the ESIN group. The duration of surgery, length of hospital stay (LOS), implant removal, complications requiring surgery, Flynn score, incidence of infection, fracture healing time, and limb length discrepancy (LLD) were similar between the two groups. Only one study reported higher incidences of fracture nonunion or delayed healing in the ESIN group. Conclusion: SMP is an effective and safe intervention superior to ESIN in reducing soft tissue irritation, angular deformation and radiation time. Given the presence of potential bias and heterogeneity, surgeons should select the treatment that would provide the best outcomes for EBL, LOS, operation time, and bone nonunion or delayed healing based on their experience. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023404118, Identifier PROSPERO (CRD42021228512).

Can Electronic Nose Replace Human Nose?-An Investigation of E-Nose Sensor Responses to Volatile Compounds in Alcoholic Beverages.

Electronic nose (E-nose) technology is frequently attempted to simulate the human olfactory system to recognize complex odors. Metal oxide semiconductors (MOSs) are E-noses' most popular sensor materials. However, these sensor responses to different scents were poorly understood. This study investigated the characteristic responses of sensors to volatile compounds in a MOS-based E-nose platform, using baijiu as an evaluation system. The results showed that the sensor array had distinctive responses for different volatile compounds, and the response intensities varied depending on the sensors and the volatile compounds. Some sensors had dose-response relationships in a specific concentration range. Among all the volatiles investigated in this study, fatty acid esters had the greatest contribution to the overall sensor response of baijiu. Different aroma types of Chinese baijiu and different brands of strong aroma-type baijiu were successfully classified using the E-nose. This study provided an understanding of detailed MOS sensor response with volatile compounds, which could be further applied to improve the E-nose technology and its practical application in food and beverages.

Motor neuron-specific RhoA knockout delays degeneration and promotes regeneration of dendrites in spinal ventral horn after brachial plexus injury.

Dendrites play irreplaceable roles in the nerve conduction pathway and are vulnerable to various insults. Peripheral axotomy of motor neurons results in the retraction of dendritic arbors, and the dendritic arbor can be re-expanded when reinnervation is allowed. RhoA is a target that regulates the cytoskeleton and promotes neuronal survival and axon regeneration. However, the role of RhoA in dendrite degeneration and regeneration is unknown. In this study, we explored the potential role of RhoA in dendrites. A line of motor neuronal RhoA conditional knockout mice was developed by crossbreeding HB9Cre+ mice with RhoAflox/flox mice. We established two models for assaying dendrite degeneration and regeneration, in which the brachial plexus was transection or crush injured, respectively. We found that at 28 days after brachial plexus transection, the density, complexity, and structural integrity of dendrites in the ventral horn of the spinal cord of RhoA conditional knockout mice were slightly decreased compared with that in Cre mice. Dendrites underwent degeneration at 7 and 14 days after brachial plexus transection and recovered at 28-56 days. The density, complexity, and structural integrity of dendrites in the ventral horn of the spinal cord of RhoA conditional knockout mice recovered compared with results in Cre mice. These findings suggest that RhoA knockout in motor neurons attenuates dendrite degeneration and promotes dendrite regeneration after peripheral nerve injury.

Reduction in arsenic intake from water has different impacts on lung cancer and bladder cancer in an arseniasis endemic area in Taiwan.

BACKGROUND: Excessive arsenic intake has a detrimental effect on human health, as reflected in an increase in cancer incidence. In an area on the southwest coast of Taiwan, arsenic intake from well water since the 1920s had caused an exceptionally high mortality from cancer. Municipal water has become available to people living in the arseniasis endemic area since the early 1970s. This study explored the impacts of reduction in arsenic intake from water on lung cancer and bladder cancer in the arseniasis endemic area in Taiwan. METHODS: Chart records of 23,013 patients diagnosed with bladder cancer and 93,633 patients with lung cancer from 1979 to 2003 were retrieved from the Taiwan Cancer Registry Center. We used the age-period-cohort model to study the changes in the incidence of lung cancer and bladder cancer in the arseniasis endemic area and the rest of Taiwan. RESULTS: Three decades after municipal water supply to the arseniasis and black foot disease endemic area (BFDEA), we saw a marked decrease in the incidence of both bladder cancer and lung cancer in the area, especially for those in the later cohorts. The relative risk (RR) of getting a bladder cancer for people living in BFDEA when compared with those in the rest of Taiwan has dropped from 20 for the early cohorts to 5 for the late cohorts. As to lung cancer, the RR has decreased from 8 to between 1.5 and 2. CONCLUSION: Reduction in arsenic intake from water has a positive impact on the incidence of both lung and bladder cancer; however, while RR for lung cancer has dropped to below 2, RR for bladder cancer remained at around 5. The difference may be because (1) there are other risk factors beside the well-water intake or (2) bladder cancer may have longer latency period for excessive arsenic exposure than lung cancer. More studies are required to understand the causes behind the difference in RR for these two types of cancer.

Genome-Wide Association Study Dissects Resistance Loci against Bacterial Blight in a Diverse Rice Panel from the 3000 Rice Genomes Project.

BACKGROUND: Bacterial blight (BB), caused by Xanthomonas oryzae pv. oryzae (Xoo) is one of the most devastating bacterial diseases of rice in temperate and tropical regions. Breeding and deployment of resistant cultivars carrying major resistance (R) genes has been the most effective approach for BB management. However, because of specific interaction of each R gene with the product of the corresponding pathogen avirulence or effector gene, new pathogen strains that can overcome the deployed resistance often emerge rapidly. To deal with ever-evolving Xoo, it is necessary to identify novel R genes and resistance quantitative trait loci (QTL). RESULTS: BB resistance of a diverse panel of 340 accessions from the 3000 Rice Genomes Project (3 K RGP) was evaluated by artificial inoculation with four representative Xoo strains, namely Z173 (C4), GD1358 (C5), V from China and PXO339 (P9a) from Philippines. Using the 3 K RG 4.8mio filtered SNP Dataset, a total of 11 QTL associated with BB resistance on chromosomes 4, 5, 11 and 12 were identified through a genome-wide association study (GWAS). Among them, eight resistance loci, which were narrowed down to relatively small genomic intervals, coincided with previously reported QTL or R genes, e.g. xa5, xa25, xa44(t). The other three QTL were putative novel loci associated with BB resistance. Linear regression analysis showed a dependence of BB lesion length on the number of favorable alleles, suggesting that pyramiding QTL using marker-assisted selection would be an effective approach for improving resistance. In addition, the Hap2 allele of LOC_Os11g46250 underlying qC5-11.1 was validated as positively regulating resistance against strain C5. CONCLUSIONS: Our findings provide valuable information for the genetic improvement of BB resistance and application of germplasm resources in rice breeding programs.

Untargeted Headspace-Gas Chromatography-Ion Mobility Spectrometry in Combination with Chemometrics for Detecting the Age of Chinese Liquor (Baijiu).

This paper proposes the combination of headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and chemometrics as a method to detect the age of Chinese liquor (Baijiu). Headspace conditions were optimized through single-factor optimization experiments. The optimal sample preparation involved diluting Baijiu with saturated brine to 15% alcohol by volume. The sample was equilibrated at 70 °C for 30 min, and then analyzed with 200 µL of headspace gas. A total of 39 Baijiu samples from different vintages (1998-2019) were collected directly from pottery jars and analyzed using HS-GC-IMS. Partial least squares regression (PLSR) analysis was used to establish two discriminant models based on the 212 signal peaks and the 93 identified compounds. Although both models were valid, the model based on the 93 identified compounds discriminated the ages of the samples more accurately according to the goodness of fit value (R2) and the root mean square error of prediction (RMSEP), which were 0.9986 and 0.244, respectively. Nineteen compounds with variable importance for prediction (VIP) scores > 1, including 11 esters, 4 alcohols, and 4 aldehydes, played vital roles in the model established by the 93 identified compounds. Overall, we determined that HS-GC-IMS combined with PLSR could serve as a rapid and accurate method for detecting the age of Baijiu.

Genome-Wide Association Analysis of the Genetic Basis for Sheath Blight Resistance in Rice.

BACKGROUND: Sheath blight (ShB), caused by Rhizoctonia solani Kühn, is one of the most destructive rice diseases. Developing ShB-resistant rice cultivars represents the most economical and environmentally sound strategy for managing ShB. RESULTS: To characterize the genetic basis for ShB resistance in rice, we conducted association studies for traits related to ShB resistance, namely culm length (CL), lesion height (LH), and relative lesion height (RLH). Combined a single locus genome-wide scan and a multi-locus method using 2,977,750 single-nucleotide polymorphisms to analyse 563 rice accessions, we detected 134, 562, and 75 suggestive associations with CL, LH, and RLH, respectively. The adjacent signals associated with RLH were merged into 27 suggestively associated loci (SALs) based on the estimated linkage disequilibrium blocks. More than 44% of detected RLH-SALs harboured multiple QTLs/genes associated with ShB resistance, while the other RLH-SALs were putative novel ShB resistance loci. A total of 261 ShB resistance putative functional genes were screened from 23 RLH-SALs according to bioinformatics and haplotype analyses. Some of the annotated genes were previously reported to encode defence-related and pathogenesis-related proteins, suggesting that quantitative resistance to ShB in rice is mediated by SA- and JA-dependent signalling pathways. CONCLUSIONS: Our findings may improve the application of germplasm resources as well as knowledge-based ShB management and the breeding of ShB-resistant rice cultivars.

[Expression of autophagy-related protein Beclin-1 and microtubule-associated protein 2 light chain 3 in periodontal ligament cells in orthodontic tooth pressure areas].

OBJECTIVE: To investigate the expression of autophagy-related protein Beclin-1 and microtubule-associated protein 2 light chain 3 (LC3Ⅱ) in periodontal ligament cells in orthodontic tooth pressure areas. METHODS: Sixty male SD rats were randomly divided into a blank control group and nine experimental groups. In the experimental groups, 0.392 N orthodontic force was used to move the first right upper molars for 15 min, 30 min, 1 h, 2 h, 4 h, 12 h, 1 d, 3 d, or 7 d. The blank control group did not receive any treatment. The rats were euthanized. Changes in the morphology of the periodontal membrane in the pressure areas were observed through hematoxylin and eosin (HE) staining. The expression levels of Beclin-1 and LC3Ⅱ were detected by immunohistochemical staining, and tartrate-resistant acid phosphatase (TRAP) staining was performed for the counting of osteoclasts. RESULTS: The HE stains showed that the hyalinization of the periodontal ligament appeared in the pressure areas after 1 day of exertion and was gradually aggravated. The immunohistochemical stains showed that the expression levels of Beclin-1 and LC3Ⅱ in the experimental groups gradually increased, peaked after 1 h, and then gradually decreased. The expression levels peaked again after 1 d, then decreased to baseline levels at 7 d of exertion. Beclin-1 and LC3Ⅱ were expressed in the osteoclasts. The TRAP stains indicated that the number of osteoclasts started to increase after 1 day. CONCLUSIONS: Autophagy may participate in the process of periodontal ligament reconstruction in orthodontic tooth pressure areas by mediating the hyalinization of periodontal ligament and affecting the biological effects of osteoclasts.

Hippo-YAP signaling pathway regulates autophagy of human periodontal ligament cells under cyclic tensile stress / 华西口腔医学杂志

OBJECTIVES@#This work aimed to investigate the molecular mechanism of cyclic tensile stress (CTS) stimulating autophagy in human periodontal ligament cells (hPDLCs).@*METHODS@#hPDLCs were isolated and cultured from normal periodontal tissues. hPDLCs were loaded with tensile stress by force four-point bending extender to simulate the autophagy of hPDLCs induced by orthodontic force du-ring orthodontic tooth movement. XMU-MP-1 was used to inhibit the Hippo signaling pathway to explore the role of the Hippo-YAP signaling pathway in activating hPDLC autophagy by tensile stress. The expression levels of autophagy-related genes (Beclin-1, LC3, and p62) in hPDLCs were detected by real-time quantitative polymerase chain reaction. Western blot was used to detect the expression levels of autophagy-related proteins (Beclin-1, LC3-Ⅱ/LC3-Ⅰ, and p62) and Hippo-YAP pathway proteins (active-YAP and p-YAP) in hPDLCs. Immunofluorescence was used to locate autophagy-related proteins (LC3-Ⅱand p62) and Hippo-YAP pathway proteins (active-YAP) of hPDLCs.@*RESULTS@#CTS-activated autophagy in hPDLCs and expression of autophagy-related proteins initially increased and then decreased; it began to increase at 30 min, peaked at 3 h, and decreased (P<0.05). CTS increased the expression of active-YAP protein and decreased the expression of p-YAP protein (P<0.05). When XMU-MP-1 inhibited the Hippo-YAP signaling pathway (P<0.05), active-YAP protein was promoted to enter the nucleus and autophagy expression was enhanced (P<0.05).@*CONCLUSIONS@#The Hippo-YAP signaling pathway is involved in the regulation of autophagy activation in hPDLCs under CTS.

The benefits of Tai Chi and brisk walking for cognitive function and fitness in older adults.

The purpose of this study was to investigate the benefits of exercises with different cognitive demands for cognitive functions (Executive and non-Executive) in healthy older adults. A cross-sectional design was adopted. In total, 84 healthy older adults were enrolled in the study. They were categorized into the Tai Chi group (TG), the brisk walking group (BG) or the control group (CG). Each participant performed the Stroop task and a digit comparison task. The Stroop task included the following three conditions: a naming condition, an inhibition condition and an executive condition. There were two experimental conditions in the digit comparison task: the non-delay condition and the delay condition. The results indicated that participants of the TG and BG revealed significant better performance than the CG in the executive condition of cognitive tasks and fitness. There was no significant difference of reaction time (RT) and accuracy rate in the inhibition and delay conditions of cognitive tasks and fitness between the TG and BG. The TG showed shorter reaction time in the naming and the executive conditions, and more accurate in the inhibition conditions than the BG. These findings demonstrated that regular participation in brisk walking and Tai Chi have significant beneficial effects on executive function and fitness. However, due to the high cognitive demands of the exercise, Tai Chi benefit cognitive functions (Executive and non-Executive) in older adults more than brisk walking does. Further studies should research the underlying mechanisms at the behavioural and neuroelectric levels, providing more evidence to explain the effect of high-cognitive demands exercise on different processing levels of cognition.

Facile synthesis of ultra-small PbSe nanorods for photovoltaic application.

Nanocrystal array solar cells based on lead chalcogenide quantum dots (QDs) have recently achieved a high power conversion efficiency of over 8%. The device performance is expected to further increase by using 1-dimensional nanorods (NRs), due to their improved carrier transport over zero-dimensional quantum dots. However, previously reported PbSe NRs have not been used in solar cells mainly because of their large diameters, resulting in a small bandgap unsuitable for photovoltaic application. In this work, we have demonstrated a new method for synthesizing monodisperse ultra-small PbSe NRs with the diameter approaching 2 nm (Eg > 1.2 eV), which can be attributed to the use of diphenylphosphine (DPP) and trans-2-octenoic acid (t-2-OA). The introduction of trace DPP can greatly lower the reaction temperature, leading to reduced diameters for the obtained PbSe NRs as well as largely increased yield. The use of short-chain t-2-OA together with oleic acid as capping ligands results in high monomer reactivity, fast nucleus diffusion and high growth rate, which realize the anisotropic growth of ultra-small PbSe NRs at low reaction temperatures. The PbSe NRs show n-type properties and high electron mobility as measured using field-effect transistors. The PbSe NRs with narrow diameters also demonstrate a suitable bandgap for photovoltaic application. They are used for the first time in solar cells and their improved efficiency is demonstrated when used together with QDs.