Prevalence and bidirectional association of sleep quality and gut health among Chinese midwives: a large population, multi-center cross-sectional study.

Background: Shift work can disrupt sleep quality and gut health. Nurses and midwives constitute approximately half of the global healthcare shift-working workforce. Our previous study revealed that most midwives were experiencing suboptimal health conditions, characterized by poor sleep quality and a high prevalence of gastrointestinal diseases. The gut-brain axis theory highlights the potential interplay between sleep quality and gut health. However, limited research focuses on this relationship among midwives. Methods: A cross-sectional survey included 2041 midwives from 87 Chinese hospitals between March and October 2023. Participants completed standardized questionnaires assessing sleep quality, gut health, depression, anxiety, and work stress. Binary logistic regression analyzed factors associated with poor sleep, and multiple linear regression examined the influence of sleep quality on gut health. Results: Over 60% of midwives reported poor sleep, with many experiencing gastrointestinal disorders. We observed a bidirectional relationship between sleep quality and gut health among midwives. After multivariable adjustments, midwives with higher gut health scores were more likely to experience poor sleep quality (odds ratio = 1.042, 95% confidence interval = 1.03-1.054). Conversely, midwives with higher sleep quality scores were also more likely to have poor gut health (ß = 0.222, 95% confidence interval = 0.529-0.797). These associations remained robust across sensitivity analyses. Furthermore, depression, anxiety, and work stress significantly affected both sleep quality and gut health among midwives. Conclusion: This study enhances our understanding of the intricate relationship between sleep quality and gut health among midwives. Poor gut health was associated with a higher risk of poor sleep, and vice versa. To improve the overall wellbeing of midwives, the findings emphasize the importance of addressing poor sleep quality and promoting gut health through maintaining a healthy diet, lifestyle, and good mental health. Further studies are needed to confirm our findings and clarify the underlying mechanisms.

Association between prepregnancy body mass index or gestational weight gain and adverse pregnancy outcomes among Chinese women with gestational diabetes mellitus: a systematic review and meta-analysis.

OBJECTIVE: The association between prepregnancy body mass index (BMI) or gestational weight gain (GWG) and adverse pregnancy outcomes among Chinese women with gestational diabetes mellitus (GDM) is unknown. This study aims to evaluate such association by synthesising the evidence. DESIGN: Systematic review and meta-analysis. DATA SOURCES: PubMed, Web of Science, Scopus, EMBASE, China Biology Medicine disc, China National Knowledge Infrastructure, Wangfang, and China Science and Technology Journal Database searched from inception to 11 August 2023. ELIGIBILITY CRITERIA: Prospective cohort studies, retrospective cohort studies and case-control studies estimating the relationship of abnormal prepregnancy BMI (including underweight, overweight or obesity) or inappropriate GWG (including excess GWG or insufficient GWG) with adverse pregnancy outcomes of interest were included. Outcomes included macrosomia, caesarean section, preterm birth, gestational hypertension, large for gestational age (LGA) and small for gestational age (SGA). DATA EXTRACTION AND SYNTHESIS: Two reviewers independently selected studies, extracted the data and assessed the risk of bias. OR estimate and its 95% CI were pooled using Stata software fixed-effect model. Subgroup analysis, meta-regression and sensitivity analysis were performed to ensure credibility of the results. RESULTS: Twenty-three studies (eighteen retrospective cohort studies, three prospective cohort studies and two case control studies) involving 57 013 Chinese women with GDM were identified. Meta-analysis results showed that compared with GDM women with normal weight, GDM women with underweight were at a higher risk of SGA (OR=1.79 (1.54 to 2.07), five studies involving 31 967 women); women with overweight had higher risks of macrosomia (OR=1.65 (1.49 to 1.82), eleven studies involving 41 683 women), caesarean section (OR=1.48 (1.38 to 1.59), ten studies involving 34 935 women), preterm birth (OR=1.27 (1.13 to 1.43), eight studies involving 38 295 women) and LGA (OR=1.73 (1.54 to 1.95), seven studies involving 31 342 women) and women with obesity had higher risks of macrosomia (OR=2.37 (2.04 to 2.76), eleven studies involving 41 683 women), caesarean section (OR=2.07 (1.84 to 2.32), nine studies involving 34 829 women), preterm birth (OR=1.31 (1.09 to 1.57), eight studies involving 38 295 women) and LGA (OR=2.63 (2.15 to 3.21), six studies involving 31 236 women). Regard to GWG, compared with Chinese GDM women with sufficient GWG, GDM women with excessive GWG had higher risks of macrosomia (OR=1.74 (1.58 to 1.92), twelve studies involving 40 966 women), caesarean section (OR=1.44 (1.36 to 1.53), nine studies involving 36 205 women) and LGA (OR=2.12 (1.96 to 2.29), twelve studies involving 42 342 women); women with insufficient GWG conversely had higher risks of preterm birth (OR=1.59 (1.45 to 1.74), nine studies involving 37 461 women) and SGA (OR=1.38 (1.27 to 1.51), ten studies involving 41 080 women). CONCLUSIONS: For Chinese women with GDM, abnormal prepregnancy BMI or inappropriate GWG were related to higher risks of many adverse pregnancy outcomes. Therefore, medical staff should pay more attention to the weight management of GDM women during pregnancy.

Entropy-Driven Phase Transition in Nanonucleation via Reciprocal Relations.

Depletion forces, commonly modeled with rigid body assumptions, inadequately describe nanoparticle behavior. This study introduces the roles of Soret and Dufour effects in nanoparticle systems, focusing on mass and energy gradient interchange. The Dufour effect drives energy flow through mass gradients, which implies the possibility of driving the energy flow near the nanoparticles to induce phase transitions via manipulating the monomer concentrations. Our experimental platform confirmed these theories, synthesizing HCP quantum dots from Au, Ag, Pd, and mixed halide perovskites under varied precursor concentrations. By analyzing energy flow and nucleation dynamics through the Dufour effect, we mapped phase transition thresholds, linking them to material entropy. This study provides insight into nanoparticle assembly and phase behavior, highlighting the significance of entropy in nucleation dynamics.

The exploration of optimal gestational weight gain after oral glucose tolerance test for Chinese women with gestational diabetes mellitus.

Now, no recommendations of gestational weight gain (GWG) after gestational diabetes mellitus (GDM) diagnosis for Chinese women was made. This study aimed to explore the optimal GWG after oral glucose tolerance test (OGTT) for Chinese women with GDM. The GWG status of 11,570 women was retrospectively analyzed. Binary regression model and restricted cubic spline were used to estimate the association between GWG after OGTT and the predicted probability of adverse outcomes. Based on above, the optimal GWG was defined as the range that not exceed 1% increase in the predicted probability from the lowest point. Results shown that every increased one unit GWG after OGTT was associated with higher risks of macrosomia, cesarean section and LGA, and lower risk of preterm birth. According to the WHO and Working Group on Obesity in China (WGOC) recommended pre-pregnancy BMI category, the optimal GWG were proposed: 3.66 to 6.66 kg/3.66 to 6.66 kg in underweight group, 3.07 to 6.50 kg/3.02 to 6.40 kg in normal weight group, 1.06 to 2.73 kg/0 to 1.99 kg in overweight group, and not applicable/- 0.22 to 2.53 kg in obese group, respectively. Therefore, it is necessary to classified Chinese population based on the WGOC recommended pre-pregnancy BMI category, that influenced the contribution of pre-pregnancy BMI groups and the optimal GWG recommendation for GDM women with overweight or obesity.

Risk factors and glycaemic control in small-for-gestational-age infants born to mothers with gestational diabetes mellitus: a case-control study using propensity score matching based on a large population.

BACKGROUND: Small for gestational age (SGA) poses a significant concern for newborns, being linked to neonatal complications and potential metabolic disorders in adulthood, especially when born to mothers with gestational diabetes mellitus (GDM), elevating their risk of complications and mortality. However, the pregnancy risk factors and glycaemic control associated with SGA infants born to mothers with GDM remain unclear. AIM: To identify the pregnancy risk factors and glycaemic control associated with SGA infants born to mothers with GDM. METHOD: This case-control study was conducted among 1910 women with GDM in China. Data were collected by the integrated electronic medical record system. Using 1:4 propensity score matching analysis, we adjusted for gestational age as confounder. Univariate and multivariate analyses were performed to identify risk factors. RESULTS: Risk factors for SGA born to mothers with GDM included a history of low birth weight, gestational hypertension, oligohydramnios, short maternal height, underweight pre-pregnancy body mass index and inadequate weight growth. While SGA was protected by weakly positive ketonuria levels in the first trimester, multiparous, anaemia and previous uterine scar were protective factors for SGA. Moreover, 2-hour postprandial glucose and haemoglobin A1c in the second trimester, as well as the 0-hour and 2-hour 75 g oral glucose tolerance test (OGTT) were linked to risk of SGA. CONCLUSIONS: SGA infants are the result of multifactorial interactions among GDM pregnant women. Notably, glycaemic control levels were associated with SGA. There is a need for enhanced perinatal monitoring and antenatal care to reduce SGA.

Effect of different antibacterial agents doping in PET-based electrospun nanofibrous membranes on air filtration and antibacterial performance.

In order to reduce the particulate matter pollution to human health in producing environments, series of polyethylene terephthalate/polyvinyl alcohol (PET/PVA) based nanofibrous membranes were fabricated and investigated the dust collection and antibacterial activity. Silver nanoparticles (AgNPs), berberine (Ber) and titanium oxide nanoparticles (TiO2NPs) were selected as antibacterial agents. These novel membranes were well-characterized using SEM, FTIR, TG, etc. techniques. Results of the dust filtration showed that PET/PVA/Ag membrane had the best filtration efficiency of 99.87% for sodium chloride (NaCl) and 99.89% for dioctyl sebacate (DEHS), held low pressure drop of 160.1 Pa for NaCl and 165.3 Pa for DEHS, and posed a high tensile strength of 4.91 MPa. The bacteriostasis studies exhibited that PET/PVA/TiO2 and PET/PVA/Ag membrane showed the highest bacteriological effect on Escherichia coli (98.7%) and Staphylococcus aureus (95.9%), respectively. Meanwhile, in vitro cytotoxicity test indicated no potential cytotoxicity existed in the cell culture process of these two antibacterial membranes. Moreover, the charge distribution in the nanofibers was increased by these antibacterial agents to improve the filtration performance. The dust filtration process synergistically promoted with the antibacterial process in the antibacterial membranes. It was expected that these membranes could be efficient filter medias with broad application prospects in the field of individual protection.

Rashba Effect and Spin-Dependent Excitonic Properties in Chiral Two-Dimensional/Three-Dimensional Composite Perovskite Films.

Among various chiral semiconductor materials, chiral two-dimensional (2D)/three-dimensional (3D) composite perovskites (CPs) offer the benefits of strong interface asymmetry and energy transfer between 2D and 3D phases, making the chiral CPs promising for spintronic devices. Therefore, understanding their spintronic properties will be greatly important for expanding their relevant applications. In this work, we synthesized one pair of chiral 2D/3D CP films. Their Rashba effect and spin relaxation process have been investigated by polarization-dependent femtosecond transient absorption spectroscopy. Interestingly, under left- and right-handed circularly polarized light (CPL) excitation, a two-photon emission intensity difference is observed in chiral 2D/3D CP films at 298 K. This work sheds light on the spin-dependent excitonic characteristics of chiral 2D/3D CPs and confirms the feasibility of their application in near-infrared CPL detection.

Effect of depressive symptoms on quality of work life in female nurses: a cross-sectional study using propensity score matching.

Background: Female nurses have been considered as a vulnerable population in the context of mental health, due to the nature of their work, which can be stressful and emotionally taxing. Understanding the relationship between depressive symptoms and quality of work life (QWL) can contribute to improving mental health and job performance. However, limited studies have focused on the effect of depressive symptoms on QWL in female nurses. Objectives: The present study aimed to assess the effect of depressive symptoms on female nurses' QWL using propensity score matching (PSM). Methods: A cross-sectional, online study using convenience sampling was conducted among 1,401 female nurses in China. PSM was used to minimize the impact of potential confounders between no depressive symptoms and depressive symptoms. Stepwise multiple linear regression analyses were performed on the PSM samples to explore the effects of depressive symptoms on the QWL. Results: The results revealed there were 33.5% of the female nurses reported depressive symptoms before PSM. And female nurses in this study had a moderate level of QWL before PSM (122.11 ± 18.15), which remained steady after PSM (118.33 ± 18.04). After PSM, the final sample contained 864 female nurses. Stepwise multiple linear regression results indicated that depressive symptoms were the most strongly associated with QWL (ß = -0.454, p < 0.001). Conclusion: This study highlights the importance of developing mental health plans and psychological interventions for female nurses to maintain mental health and QWL, which is critical to the nursing workforce's sustainability.

Association between plant-based or animal-based dietary pattern and plasma glucose during oral glucose tolerance test among Chinese women with gestational diabetes mellitus: a prospective cohort study.

OBJECTIVE: This study explored whether plant-based and animal-based dietary patterns are associated with plasma glucose levels during oral glucose tolerance test in women with gestational diabetes mellitus (GDM). DESIGN: A prospective cohort study was conducted using a Food Frequency Questionnaire to collect dietary data. Dietary patterns were derived using principal component analysis. Multivariate logistic regression analysis was performed to explore the association between dietary patterns and plasma glucose levels. Stratified analyses were conducted according to maternal age, prepregnancy body mass index (BMI) and other confounders. SETTING AND PARTICIPANTS: The study, conducted in January 2022 in two hospitals in Fujian, China, involved 424 women diagnosed with GDM using a 75 g 2-hour oral glucose tolerance test at 24-28 gestational weeks. RESULTS: Six maternal dietary patterns (plant based and animal based) were identified. Participants with plant-based pattern had lower 2-hour plasma glucose levels than those with animal-based pattern (ß=-0.314; 95% CI (-0.596 to -0.032)). After adjusting the regression model covariates, this significant association remained (ß=-0.288; 95% CI (-0.568 to -0.008)) and appeared more pronounced in women aged 30 years or above and those with prepregnancy BMI<24 kg/m2. CONCLUSIONS: Plant-based pattern is associated with lower plasma glucose levels in women with GDM, which is valuable information for dietary counselling and intervention.

The effects of plant-based dietary patterns on the risk of developing gestational diabetes mellitus: A systematic review and meta-analysis.

BACKGROUND: The worldwide prevention of gestational diabetes mellitus (GDM) is a significant health challenge. Plant-based dietary patterns are a series dietary habits that emphasized foods derived from plant sources more and from animal foods less. Now, no consensus exists on the effects of plant-based dietary patterns on the incident of GDM. OBJECTIVE: This study aimed to estimate the effects of plant-based dietary patterns on the risk of developing GDM. METHODS: This systematic review was conducted following the checklist of PRISMA. Six electronic databases including PubMed, Embase, Web of Science, China National Knowledge Infrastructure, Wangfang, and Chinese Scientific Journals Database were searched from inception to November 20, 2022. A fixed or random effect model was used to synthesize results of included studies. Then, subgroup analysis, meta-regression and sensitivity analysis were performed to assure the reliability and stability of the results. RESULTS: Ten studies including 32,006 participants were identified. The results of this study showed that the better adherence to the plant-based dietary patterns was related to the lower risk of developing GDM (RR = 0.88[0.81 to 0.96], I2 = 14.8%). The slightly stronger association between plant-based diets and the risk of developing GDM was found when healthy plant-based dietary pattern index was included in pooled estimate (RR = 0.86[0.79 to 0.94], I2 = 8.3%), compared with that unhealthy one was included (RR = 0.90[0.82 to 0.98], I2 = 8.3%). CONCLUSION: The plant-based dietary patterns are associated with a lower risk of developing GDM. Furthermore, healthy plant-based dietary patterns are more recommended than unhealthy one. It is significant to help medical staff to guide pregnant women to choose reasonable diets.

Spatially Correlated Chirality in Chiral Two-Dimensional Perovskites Revealed by Second-Harmonic-Generation Circular Dichroism Microscopy.

Understanding the chiral mechanism of chiral hybrid perovskites is a prerequisite for developing relevant chiroptoelectronic applications. Although conventional circular dichroism (CD) spectroscopy can be used to characterize chirality in chiral perovskites, it has a low signal-to-noise ratio and can provide only information about macroscopic chirality. Herein, with the aim of revealing the microscopic chiral mechanism in chiral perovskites, we utilize a spacer cation alloying strategy to construct chiral two-dimensional perovskites. For the first time, we demonstrate second-harmonic-generation CD microarea imaging in chiral perovskite thin films to unveil their spatially correlated chirality. In combination with theoretical calculations, it is revealed that the spatially correlated chirality is caused by localized out-of-plane supramolecular orientations. This work will not only advance the understanding of the mechanism of chiroptical activity in chiral perovskites but also provide inspiration for the rational design and synthesis of perovskites for chirality-related nonlinear optoelectronic devices.

Hydrophobic/oleophobic nanofibrous filter media with bead-on-string structure for efficient personal protection of dust in mines.

Pneumoconiosis in mines occupied more than 90% of the total number of occupational diseases, poses tremendous pressure and challenges on the development of personal protection materials with high dust filtration efficiency and long-lasting comfortable wearing. In this study, a kind of polyethylene terephthalate (PET) based filter media with the bead-on-string structure and hydrophobic/oleophobic property was designed and fabricated by electrospinning technology. Nanoscale silicon dioxide (SiO2NPs) and fluorinated polyurethane (PU) used in this work were benefited for the microstructure, surface energy and hydrophobic/oleophobic property, respectively. The morphology and composition of the membranes were conducted by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and fourier transform infrared spectroscopy (FTIR). Furthermore, the filtration performance, pressure drop, moisture permeability and breathing comfortable performance were measured for the study of personal protection of dust. The results showed that at the air flow of 85 L min-1, PET/SiO2/FPU double-layer nanofibrous membrane showed high filtration efficiency and low pressure drop with the filtration efficiency of 99.96%, pressure drop of 142.5 Pa and quality factor of 0.055 Pa-1, respectively. A long term of 24 h water vapor test had proved that this membrane held an outstanding moisture permeability ability of 5296.325 g (m2 24 h)-1. Compared with the commercial 3701CN filter media, the advantages of the regular breathing frequency and strong heart rate control ability indicated that this PET/SiO2/FPU double-layer membrane had the better wearing comfortable performance with broad application prospects in the personal protection of dust in mines.

Mediating effect of resilience between social support and compassion fatigue among intern nursing and midwifery students during COVID-19: a cross-sectional study.

AIMS: To examine the mediating effect of resilience between social support and compassion fatigue among intern nursing and midwifery students during COVID-19. BACKGROUND: Compassion fatigue has become exceedingly common among intern nursing and midwifery students, especially during the COVID-19 pandemic. Social support and resilience can help intern nursing and midwifery students control their negative emotions, reduce compassion fatigue, and increase their well-being. However, the mediating effect of resilience between social support and compassion fatigue remains unclear. DESIGN: A multicentre cross-sectional survey. METHODS: A total of 307 intern nursing and midwifery students were recruited from November 2020 to February 2021 in tertiary grade A hospitals in China. Structural equation modelling was applied to analyse the mediating effects of resilience between social support and compassion fatigue. The Social Support Rating Scale, the 10-item Connor-Davidson Resilience Scale, and the Chinese version of the Compassion Fatigue Short Scale were used to collect data. The hypothetical path model was tested by using IBM SPSS version 26.0 and AMOS version 26.0 software. RESULTS: Intern nursing and midwifery students had moderate compassion fatigue. Social support positively affected resilience (ß = 0.514, p < 0.01). Social support negatively affected compassion fatigue (ß = - 0.310, p < 0.01), while resilience negatively affected compassion fatigue (ß = - 0.283, p < 0.01). Resilience played a mediating role between social support and compassion fatigue. CONCLUSION: Social support can directly affect the compassion fatigue of intern nursing and midwifery students during COVID-19 and indirectly through resilience. Stronger resilience can reduce compassion fatigue. Accordingly, resilience-based interventions should be developed to reduce compassion fatigue.

Alginate-oil gelator composite foam for effective oil spill treatment.

Oil spills threaten ecosystem and health seriously. Porous foams have been proved as ideal candidates for oil absorbents, however, many with poor oil retention (re-bleeding). Here, we creatively developed a composite foam oil absorbent capable of oil absorption and oil gelation, based on porous alginate foam and hydroxyl aluminum stearate oil gelator. The microstructure of alginate foam can be adjusted by the addition of t-butanol in the solvent, and long alkyl chains of gelator endow foam skeleton with good hydrophobicity, avoiding secondary pollution from traditional hydrophobic chemical modification. Interconnected skeleton decorated by oleophilic gelators contributes to high oil absorption. Oleophilic gelator can self-assemble into 3D network to entrap oils to form gels, giving rise to effective oil retention, realizing the integration of high oil absorption and oil retention. The natural abundant, low-cost composite foam would be promising for tackling oil spills.

The 3D-Printing-Accelerated Design for a Biodegradable Respirator from Tree Leaves (TRespirator).

The unpredictable coronavirus pandemic (COVID-19) has led to a sudden and massive demand for face masks, leading to severe plastic pollution. Here, we propose a method for manufacturing biodegradable masks using high-precision 3D printing technology, called "TRespirator", mainly made of banana leaves and dental floss silk fibers. By adding plastic recycling waste appropriately, TRespirator can achieve similar protection and mechanical properties as N95 masks. In addition, microorganisms attracted during the degradation of plant fibers will accelerate the degradation of microplastics. This respirator provides a new idea for solving the global problem of plastic pollution of masks.

The effects of filter characteristics of single-filter cartridge on dust removal performance with simulation and experimental analysis.

To obtain the adaptability range of the single-filter cartridge dust collector, a numerical analysis of the key component (filter cartridge) that affects the filter performance of the dust collector is carried out. The study found that the filtration air velocity gradually decreases from the top A to the bottom C of the filter cartridge surface. During the filtration process, along the surface of the filter cartridge from C to A, the pressure first drops and then rises. At C, the negative pressure is the largest, with an average of about 525 Pa. The ineffective filtration area of section A of the upper part of the filter cartridge accounts for 2/5 of the filtration area, and the concentration of the first layer of dust is y = (0.01 ± a) + 0.02 × (0.08 ± b)x exponentially decreasing. The critical particle size range that the filter cartridge can filter dust is M≥1.87 µm, and the best dust removal range of the dust collector is N≥4.625 µm. An agreement between experiment and simulating results proves the validity of simulation model and reliability of the experimental data. Enterprises can choose a reasonable dust removal method based on the research results to optimize the adaptability of the working environment and the dust collector. It also provides a theoretical basis for researchers to solve the problems in the filtration and cleaning process.

Dual-Structure PVDF/SDS Nanofibrous Membranes for Highly Efficient Personal Protection in Mines.

Pneumoconiosis in miners is considered a global problem. Improving the performance of individual protective materials can effectively reduce the incidence of pneumoconiosis. In this study, the blend membrane of sodium dodecyl sulfate and polyvinylidene fluoride with a dual structure was prepared using electrospinning techniques, and the morphological structure, fiber diameter, and filtration performance of the nanofiber membranes were optimized by adjusting the PVDF concentration and SDS content. The results show that the incorporation of SDS enabled the nanofiber membranes to show tree-like and beaded fibers. Compared with the original PVDF membrane, the small content of tree-like fibers and beaded fibers can improve the filtration efficiency and reduce the resistance of the fiber membrane. The prepared nanofiber membrane has excellent comprehensive filtration performance, and the quality factor is 0.042 pa-1 when the concentration of PVDF is 10 wt% and the addition of SDS is 0.1 wt%. Furthermore, after high-temperature treatment, the membrane could still maintain good filtration performance. The PVDF/SDS blend nanofiber membrane has outstanding filtration efficiency and good thermal stability and can fully meet the personal protection of miners in underground high-temperature operation environments.

Chiroptical Transitions of Enantiomeric Ligand-Activated Nickel Oxides.

Ligand-induced chirality in transition-metal oxide (TMO) nanostructures have great potential for designing materials with tunable chiroptical effects. Herein, a facile strategy is reported to prepare chiroptical active nickel-oxide hybrids combined with pH adjustment, and the redox treatment results in ligand transformation, which is attributable to multiple optical transitions in the TMO nanostructures. The theoretical calculation also explains the chiral origins based on their complex models based on empirical analysis. It is also shown that enantiomeric TMO nanoparticles can be used as chiral inducers for chiroptical sensitive polymerization. These results demonstrate that TMO nanostructures can provide rational control over photochemical synthesis and chiral transfer of inorganics nanoarchitecture chirality.

Authentic Intelligent Machine for Scaling Driven Discovery: A Case for Chiral Quantum Dots.

The scaling laws have long been used as evidence of science where many fundamental physics laws emerge. As emerging nanomaterials, quantum dots are also sensitive to scaling because of their strong size effect. In this work, we developed the chiral dielectric theory based on the exciton absorption mechanism to explain the increment of the dielectric constant from chirality via its dimensionality. To help researchers discover and develop scaling relevant theories, the Authentic Intelligent Machine (AIM) protocol was developed to generate and interpret experimental data in an analytical and scaling-oriented manner. We show how the AIM protocol interprets spectra such as transient absorption data of chiral quantum dots with theories, where discrepancies concerning the dielectric constant were discovered. Examples for applying the AIM protocol on other spectra, such as absorption spectra and photoluminescence spectra, are also given.

Selenocystine and Photo-Irradiation Directed Growth of Helically Grooved Gold Nanoarrows.

The fabrication of discrete nanostructures with both plasmonic circular dichroism (PCD) and chiral features is still a challenge. Here, gold nanoarrows (GNAs) with both chiroptical responses and chiral morphologies are achieved by using L-selenocystine (L-SeCys2 ) as a chiral inducer. While L-SeCys2 generates GNAs with a weak PCD signal, the irradiated L-SeCys2 (irr-L-SeCys2 ) leads to GNAs with featured helical grooves (HeliGNAs) accompanying with a strong PCD signal. It is revealed that when L-SeCys2 is photo-irradiated, the emergence of selenyl radicals plays an important role in the formation of HeliGNAs and enhancement of the chiroptical signal. In comparison with L-SeCys2 and the other kinds of sulfur-containing amino acids, the formation mechanism of helical grooves on the surface of GNAs is proposed. Both HeliGNAs and GNAs are used to discriminate amino acids by utilizing surface enhanced Raman scattering (SERS) effect. In the presence of either GNAs or HeliGNAs as the substrate, Fmoc-L-Phe shows more significant SERS than Fmoc-D-Phe. This study may advance the design of discrete plasmonic nanomaterials with both chiral morphology and potential applications in discrimination of chiral molecules.