Formation and Transformation of CdS Clusters during the Prenucleation Stage and in a Dilute Dispersion at Room Temperature.

The formation and transformation of colloidal semiconductor clusters remain poorly understood. With CdS as a model system, we show that, in the reaction of cadmium myristate (Cd(MA)2) and S powder in 1-octadecene (ODE), clusters form in the prenucleation stage of quantum dots (QDs). Called precursor compounds (PCs), the clusters can transform to magic-size clusters (MSCs) in reaction at a relatively high temperature (MSC-322 displaying optical absorption peaking at 322 nm) or in a dispersion at room temperature (MSC-360). When the reaction temperature is increased, PC-360 forms at 140 °C, while PC-322 and MSC-322 form at 180 °C. In a dispersion of cyclohexane and octylamine, MSC-322 transforms to MSC-360 via MSC-345. The MSC-345 to MSC-360 transformation displays continuous and discontinuous shifts in the optical absorption. The PCs and MSCs are a group of isomers. The present findings bring insight into the cluster formation and isomerization in the prenucleation stage of QDs and in a dispersion.

Lower-Temperature Nucleation and Growth of Colloidal CdTe Quantum Dots Enabled by Prenucleation Clusters with Cd-Te Bond Conservation.

The reason why heating is required remains elusive for the traditional synthesis of colloidal semiconductor quantum dots (QDs) of II-VI metal chalcogenide (ME). Using CdTe as a model system, we show that the formation of Cd-Te covalent bonds with individual Cd- and Te-containing compounds can be decoupled from the nucleation and growth of CdTe QDs. Prepared at an elevated temperature, a prenucleation-stage sample contains clusters that are the precursor compound (PC) of magic-size clusters (MSCs); the Cd-Te bond formation occurs at temperatures higher than 120 °C in the reaction. Afterward, the PC-to-QD transformation appears via monomers at lower temperatures in dispersion. Our findings suggest that the number of Cd-Te bonds broken in the PC reactant is similar to that of Cd-Te bonds formed in the QD product. For the traditional synthesis of ME QDs, heating is responsible for the M-E bond formation rather than for nucleation.

Pathway of Room-Temperature Formation of CdSeS Magic-Size Clusters from Mixtures of CdSe and CdS Samples.

The synthetic application of prenucleation-stage samples of colloidal semiconductor quantum dots (QDs) is in its infancy. It is shown that when two prenucleation-stage samples of binary CdSe and CdS are mixed, ternary CdSeS magic-size clusters (MSCs) grow at room temperature in dispersion. As the amount of the CdS sample increases, the optical absorption of the CdSeS MSCs blueshifts from ≈380 to ≈360 nm. It is proposed that the cluster in the CdSe sample reacts with the CdS monomer from the CdS sample. The monomer substitution reaction of CdSe by CdS can proceed continuously; thus, CdSeS MSCs with tunable compositions are obtained. The present study provides compelling evidence that clusters formed in the prenucleation stage of QDs. The clusters are precursor compounds (PCs) of MSCs, transforming at room temperature with the thermoneutrality principle of isodesmic reactions. The nucleation and growth of QDs follows a multi-step non-classical instead of one-step classical nucleation model.

Room-Temperature Formation of CdTeSe Magic-Size Clusters from Oleate-Capped CdTe Precursor Compounds via CdSe Monomer Substitution.

We report the first room-temperature synthesis of ternary CdTeSe magic-size clusters (MSCs) that have mainly the surface ligand oleate (OA). The MSCs display sharp optical absorption peaking at ∼399 nm and are thus referred to as MSC-399. They are made from prenucleation-stage samples of binary CdTe and CdSe, which are prepared by two reactions in 1-octadecene (ODE) of cadmium oleate (Cd(OA)2) and tri-n-octylphosphine chalcogenide (ETOP, E = Te and Se) at 25 °C for 120 min and 80 °C for 15 min, respectively. When the two binary samples are mixed at room temperature and dispersed in a mixture of toluene (Tol) and octylamine (OTA), the CdTeSe MSC-399 develops. Also, when the CdSe sample is added to CdTe MSC-371 in a dispersion, the transformation from CdTe MSC-371 to CdTeSe MSC-399 is seen. We propose that the MSCs develop from their precursor compounds (PCs) that are relatively transparent in optical absorption, such as CdTeSe MSC-399 from CdTeSe PC-399 and CdTe MSC-371 from CdTe PC-371. The formation of CdTeSe PC-399 undergoes monomer substitution and not anion exchange, which is the reaction of CdTe PC-371 and the CdSe monomer to produce CdTeSe PC-399 and the CdTe monomer. Our study provides evidence of monomer substitution for the transformation from binary CdTe to ternary CdTeSe PCs.

Efficacy of Acupuncture for Chronic Spontaneous Urticaria : A Randomized Controlled Trial.

BACKGROUND: The effectiveness of acupuncture for patients with chronic spontaneous urticaria (CSU), reported in a few small-scale studies, is not convincing. OBJECTIVE: To investigate whether acupuncture leads to better effects on CSU than sham acupuncture or waitlist control. DESIGN: A multicenter, randomized, sham-controlled trial. (Chinese Clinical Trial Registry: ChiCTR1900022994). SETTING: Three teaching hospitals in China from 27 May 2019 to 30 July 2022. PARTICIPANTS: 330 participants diagnosed with CSU. INTERVENTION: Participants were randomly assigned in a 1:1:1 ratio to receive acupuncture, sham acupuncture, or waitlist control over an 8-week study period (4 weeks for treatment and another 4 weeks for follow-up). MEASUREMENTS: The primary outcome was the mean change from baseline in the Weekly Urticaria Activity Score (UAS7) at week 4. Secondary outcomes included itch severity scores, self-rated improvement, and Dermatology Life Quality Index scores. RESULTS: The mean change in UAS7 (range, 0 to 42) for acupuncture from baseline (mean score, 23.5 [95% CI, 21.8 to 25.2]) to week 4 (mean score, 15.3 [CI, 13.6 to 16.9]) was -8.2 (CI, -9.9 to -6.6). The mean changes in UAS7 for sham acupuncture and waitlist control from baseline (mean scores, 21.9 [CI, 20.2 to 23.6] and 22.1 [CI, 20.4 to 23.8], respectively) to week 4 (mean scores, 17.8 [CI, 16.1 to 19.5] and 20.0 [CI, 18.3 to 21.6], respectively) were -4.1 (CI, -5.8 to -2.4) and -2.2 (CI, -3.8 to -0.5), respectively. The mean differences between acupuncture and sham acupuncture and waitlist control were -4.1 (CI, -6.5 to -1.8) and -6.1 (CI, -8.4 to -3.7), respectively, which did not meet the threshold for minimal clinically important difference. Fifteen participants (13.6%) in the acupuncture group and none in the other groups reported adverse events. Adverse events were mild or transient. LIMITATION: Lack of complete blinding, self-reported outcomes, limited generalizability because antihistamine use was disallowed, and short follow-up period. CONCLUSION: Compared with sham acupuncture and waitlist control, acupuncture produced a greater improvement in UAS7, although the difference from control was not clinically significant. Increased adverse events were mild or transient. PRIMARY FUNDING SOURCE: The National Key R&D Program of China and the Science and Technology Department of Sichuan Province.

Analysis of Factors Influencing the Stigma Associated with Postoperative Cervical Cancer Patients and the Impact of Integrated Nursing Interventions on Stigma.

Objective: To investigate the influencing factors related to stigma and nursing interventions for patients after cervical cancer surgery. Methods: The clinical data of 158 patients with cervical cancer treated with radical cervical cancer in Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology from November 2016 to December 2021 were retrospectively analyzed. The patients were divided into a research group (79 cases) and a control group (79 cases) based on the random number method. In the control group, patients were given general nursing instructions during the post-operative visit. In contrast, the research group provided comprehensive nursing interventions to patients and their families based on the observation group. The Social Impact Scale (SIS) was used to assess the patients' stigma; the Self-Rating Anxiety Scale (SAS), Trait Coping Style Questionnaire (TCSQ), and Quality of Life Questionnaire for Cancer Patients (QLQ-C30) were also used to assess the patients' pre- and post-care interventions. The patients' status was assessed before and after the intervention. Results: The SIS score (49.68±8.41) and TCSQ negative coping score (30.14±7.06) of the patients in the research group after the nursing intervention were much smaller than those in the control group, and the TCSQ positive coping score (40.36±6.51) was much larger than that of the control group (P < .05). The SAS anxiety score (31.65±7.36) was much smaller, and the QLQ-C30 score (78.65±16.59) was much larger in the research group than in the control group after the nursing intervention (P < .05). Conclusion: Risk factors affecting postoperative cervical cancer patients' sense of stigma include age 18-35 years, high school and above, employed, monthly income >3000 RMB, family history of the disease, disease duration >5 years, and postoperative chemotherapy, etc. Comprehensive clinical interventions can be given to patients with these conditions to reduce the sense of stigma.

Environmental Impact Assessment for the Use of an Orally Aerosolized Adenovirus Type-5 Vector-Based COVID-19 Vaccine in Randomized Clinical Trials.

BACKGROUND: An orally aerosolized adenovirus type-5 vector-based coronavirus disease 2019 (COVID-19) vaccine (Ad5-nCoV) has recently been authorized for boosting immunization in China. Our study aims to assess the environmental impact of the use of aerosolized Ad5-nCoV. METHODS: We collected air samples from rooms, swabs from the desks on which the vaccine nebulizer was set, mask samples from participants, and blood samples of nurses who administered the inoculation in the clinical trials. The viral load of adenovirus type-5 vector in the samples and the antibody levels against the wild-type severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain in serum were detected. RESULTS: Only one (4.00%) air sample collected before initiation of vaccination was positive and most air samples collected during and after vaccination were positive (97.96%, 100%, respectively). All nurses in trial A showed at least 4-fold increase of the neutralizing antibody against SARS-CoV-2 after initiation of the study. In trial B, the proportion of positive mask samples was 72.97% at 30 minutes after vaccination, 8.11% at day 1, and 0% at days 3, 5, and 7. CONCLUSIONS: Vaccination with the orally aerosolized Ad5-nCoV could result in some spillage of the vaccine vector viral particles in the environment and cause human exposure. Clinical Trials Registration. NCT04840992 and NCT05303584.

Macrophage Gpx4 deficiency aggravates foam cell formation by regulating the expression of scavenger receptors, ABCA1, and ABCG1.

Macrophage-derived foam cell formation is critical for the initiation and development of atherosclerosis, which contributes to atherosclerotic cardiovascular disease (ASCVD). Glutathione peroxidase 4 (GPX4), a crucial ferroptosis regulator, protects cells from excessive oxidative stress by neutralizing lipid peroxidation. However, the role of macrophage GPX4 in foam cell formation remains unknown. We reported that oxidized low-density lipoprotein (oxLDL) upregulated GPX4 expression in macrophages. Using the Cre-loxP system, we generated myeloid cell-specific Gpx4 knockout (Gpx4myel-KO ) mice. Bone marrow-derived macrophages (BMDMs) were isolated from WT and Gpx4myel-KO mice and incubated with modified low-density lipoprotein (LDL). We found that Gpx4 deficiency promoted foam cell formation and increased the internalization of modified LDL. Mechanistic studies unveiled that Gpx4 knockout upregulated scavenger receptor type A and LOX-1 expression and downregulated ABCA1 and ABCG1 expression. Collectively, our study lends a novel insight into the role of GPX4 in suppressing macrophage-derived foam cell formation and suggests GPX4 as a promising therapeutic target to interfere with atherosclerosis-related diseases.

Sex-based influential factors for dental caries in patients with schizophrenia.

BACKGROUND: Schizophrenia is a common mental disorder that seriously affects patients' daily lives and brings heavy psychological and economic burdens to their families and society. The oral problems of patients with schizophrenia are gradually gaining attention, among which dental caries are among the most common oral diseases. Sex differences may be related not only to the various clinical symptoms of schizophrenia but also to different oral hygiene statuses; therefore, the main purpose of this paper is to investigate sex differences related to influencing factors for dental caries in patients with schizophrenia. METHOD: Inpatients with schizophrenia over 18 years old were included in this study, and multidimensional indicators such as demographics, symptom and cognitive impairment assessments, medications, and the caries index of decayed, missing, and filled teeth (DMFT) were collected. An analysis of sex-based influential factors for dental caries in schizophrenia patients was performed. RESULTS: Four-hundred and ninety-six patients with schizophrenia were included, with a mean age of 46.73 ± 12.23 years, of which 142 were females and 354 were males. The mean DMFT was significantly higher in males (8.81 ± 8.50) than in females (5.63 ± 6.61, p < 0.001), and the odd ratio of caries in males to females was significantly higher as well (OR = 2.305, p < 0.001). The influential factors of caries in male patients were independently associated with age and smoking status, in which current smokers were at the highest risk for developing caries, and different smoking statuses had various influencing factors for caries. The influencing factors for caries in female patients were independently associated with age, antipsychotic dose, PANSS-positive symptoms, and MMSE levels. CONCLUSION: Our findings suggest sex differences exist among influential factors for caries in patients with schizophrenia. These risk factors may even be associated with and affect the treatment and prognosis of psychiatric symptoms in patients. Therefore, oral hygiene management of patients with schizophrenia should be enhanced. These differential factors provide new visions and ideas for formulating individual interventions, treatments, and care priorities.

Thermally-Induced Isomerization of Prenucleation Clusters During the Prenucleation Stage of CdTe Quantum Dots.

The evolution of prenucleation clusters in the prenucleation stage of colloidal semiconductor quantum dots (QDs) has remained unexplored. With CdTe as a model system, we show that substances form and isomerize prior to the nucleation and growth of QDs. Called precursor compounds (PCs), the prenucleation clusters are relatively optically transparent and can transform to absorbing magic-size clusters (MSCs). When a prenucleation-stage sample at 25, 45, or 80 °C is dispersed in a mixture of cyclohexane (CH) and octylamine (OTA) at room temperature, either MSC-371, MSC-417, or MSC-448 evolves with absorption peaking at 371, 417, or 448 nm, respectively. We propose that PC-371 forms at 25 °C, and isomerizes to PC-417 at 45 °C and to PC-448 at 80 °C. The PCs and MSCs are quasi isomers. Relatively large and small amounts of OTA favor PC-371 and PC-448 in dispersion, respectively. The present findings suggest the existence of PC-to-PC isomerization in the QD prenucleation stage.

Overexpressed IncRNA GATA3-AS1 in Preeclampsia and Its Effects on Trophoblast Proliferation and Migration by the miR-488-3p/ROCK1 Axis.

Recently, dysregulation of long noncoding RNAs (lncRNAs) has been reported to be involved in the pathogenesis of preeclampsia (PE). Here, the role and molecular mechanisms of lncRNA GATA3 antisense RNA 1, GATA3-AS1 in PE were explored. The expression of GATA3-AS1, miR-488-3p and Rho-associated coiled-coil-containing protein kinase 1 (ROCK1) in placental tissues from patients with PE was measured by reverse transcription quantitative PCR (RT-qPCR). Proliferation, migration, invasion, and apoptosis of trophoblast cells were examined by 5-ethynyl-2'-deoxyuridine (EdU), wound healing, Transwell, and flow cytometry analyses. The subcellular localization of GATA3-AS1 in trophoblast cells was determined by fluorescent hybridization (FISH) assay. The interactions among GATA3-AS1, miR-488-3p and ROCK1 were identified by luciferase reporter and RNA pulldown assays. Our results showed that GATA3-AS1 and ROCK1 were overexpressed while miR-488-3p was downregulated in placental samples with PE. Functionally, GATA3-AS1 overexpression promoted trophoblast cell apoptosis and inhibited cell proliferation, migration, and invasion. Mechanically, GATA3-AS1 acted as a molecular sponge of miR-488-3p and miR-488-3p targeted ROCK1 in trophoblast cells. In rescue assays, ROCK1 overexpression or miR-488-3p downregulation reversed the effects of GATA3-AS1 silencing on trophoblast cell phenotypes. GATA3-AS1 is overexpressed in PE and promotes PE progression by the miR-488-3p/ROCK1 axis.

Downregulation of microRNA-342-3p Eases Insulin Resistance and Liver Gluconeogenesis via Regulating Rfx3 in Gestational Diabetes Mellitus.

Gestational diabetes mellitus (GDM) is a worldwide public health problem. MicroRNAs (miRNAs) have been reported to be associated with GDM progression. We intended to figure out the function of miR-342-3p in the insulin resistance (IR) and liver gluconeogenesis in GDM. GDM mouse models were established by intraperitoneal injection of streptozocin. The expression of miR-342-3p and regulatory factor X3 (Rfx3) in placenta and pancreatic tissues of GDM mice were evaluated by reverse transcription quantitative polymerase chain reaction (RT-qPCR). GDM mice were treated with lentivirus-mediated antagomir-miR-342-3p for miR-342-3p downregulation. Enzyme-linked immunosorbent assay, hematoxylin-eosin staining, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining and periodic acid-Schiff staining were conducted to detect the influence of miR-342-3p knockdown on the levels of blood glucose, insulin, biochemical indices as well as the apoptosis and pathological changes in placenta or pancreatic tissues of GDM mice. The binding between Rfx3 and miR-342-3p was validated by dual luciferase reporter assays. miR-342-3p was upregulated and Rfx3 was downregulated in placenta and pancreatic tissues of GDM mice. Moreover, miR-342-3p bound with Rfx3 3'-UTR and therefore downregulated the expression of Rfx3. miR-342-3p expression was negatively correlated to Rfx3 expression in placenta tissues of GDM mice. In addition, miR-342-3p depletion decreased the levels of blood glucose, insulin, biochemical indices as well as restrained the apoptosis and pathological changes in GDM mouse placenta and pancreatic tissues. Furthermore, Rfx3 silencing countervailed the alleviative influence of miR-342-3p downregulation on IR and liver gluconeogenesis in GDM mice. Collectively, downregulation of miRNA-342-3p inhibits IR and liver gluconeogenesis in GDM by upregulating Rfx3, which may provide novel insight for GDM treatment.

Unveiling Mechanism of Organic Photogenerator for Hydroxyl Radicals Generation by Molecular Modulation.

Photodynamic therapy (PDT) with organic photosensitizers generally goes through the oxygen-dependent process, generating singlet oxygen and/or superoxide anion. However, the generation of reactive oxygen species is often suppressed as a result of hypoxia, one of the common features in tumors, therefore limiting the effectiveness of the tumor treatments. Consequently, it is urgent and significant to develop an oxygen-independent hydroxyl radical photogenerator and unveil the mechanism. In this work, a hydroxyl radical (·OH) photogenerator originating from the electron transfer process is engineered. Detailed mechanism studies reveal that the optimized photosensitizer, WS2D, which contains a bithiophene unit, could both promote charge carrier generation and accelerate reaction efficiency, resulting in the efficient production of ·OH. In addition, WS2D nanoparticles are constructed to improve the polydispersity and stability in aqueous solution, which exhibit excellent biocompatibility and mitochondrial targeting. Bearing the above advantages, WS2D is employed in phototheranostics, which could release ·OH effectively and damage mitochondria precisely, achieving high PDT efficiency in vitro and in vivo. Overall, this work successfully provides valuable insights into the structural design of a hydroxyl radicals (·OH) photogenerator with great practical perspectives.

Transformations Among Colloidal Semiconductor Magic-Size Clusters.

A knowledge of colloidal semiconductor magic-size clusters (MSCs) is essential for understanding how fundamental properties evolve during transformations from individual molecules to semiconductor quantum dots (QDs). Compared to QDs, MSCs display much narrower optical absorption bands; the higher cluster stability gives rise to a narrower size distribution. During the production of binary QDs such as II-VI metal (M) chalcogenide (E) ones, binary ME MSCs observed were interpreted as side products and/or the nuclei of QDs. Prior to the current development of our two-step approach followed by our two-pathway model, it had been extremely challenging to synthesize MSCs as a unique product without the nucleation and growth of QDs. With the two-step approach, we have demonstrated that MSCs can be readily engineered as a sole product at room temperature from a prenucleation stage sample, also called an induction period (IP) sample. It is important that we were able to discover that the evolution of the MSCs follows first-order reaction kinetics behavior. Accordingly, we proposed that a new type of compound, termed as "precursor compounds" (PCs) of MSCs, was produced in an IP sample. Such PCs are optically transparent at the absorption peak positions of their MSC counterparts as well as to longer wavelengths. It is thought that quasi isomerization of a single PC results in the development of one MSC.In this Account, we provide an overview of our latest advances regarding the transformations among binary CdE MSCs as well as from binary CdTe to ternary CdTeSe MSCs. Optical absorption spectroscopy has been employed to study these transformations, all of which display well-defined isosbestic points. We have proposed that these MSC to MSC transformations occur via their corresponding PCs, also called immediate PCs. It is reasonable that the as-synthesized PC (in an IP sample) and the immediate PC (in an incubated and/or diluted sample) probably have different configurations. A transformation between two PCs may involve an intermolecular reaction, with either first-order reaction kinetics or a more complicated time profile. A transformation between one immediate PC and its counterpart MSC may contain an intramolecular reaction. The present Account, which addresses the PC-enabled MSC transformations with isosbestic points probed by optical absorption spectroscopy, calls for more experimental and theoretical attention to understand these magic species and their transformation processes more precisely.

A CHCHD6-APP axis connects amyloid and mitochondrial pathology in Alzheimer's disease.

The mechanistic relationship between amyloid-beta precursor protein (APP) processing and mitochondrial dysfunction in Alzheimer's disease (AD) has long eluded the field. Here, we report that coiled-coil-helix-coiled-coil-helix domain containing 6 (CHCHD6), a core protein of the mammalian mitochondrial contact site and cristae organizing system, mechanistically connects these AD features through a circular feedback loop that lowers CHCHD6 and raises APP processing. In cellular and animal AD models and human AD brains, the APP intracellular domain fragment inhibits CHCHD6 transcription by binding its promoter. CHCHD6 and APP bind and stabilize one another. Reduced CHCHD6 enhances APP accumulation on mitochondria-associated ER membranes and accelerates APP processing, and induces mitochondrial dysfunction and neuronal cholesterol accumulation, promoting amyloid pathology. Compensation for CHCHD6 loss in an AD mouse model reduces AD-associated neuropathology and cognitive impairment. Thus, CHCHD6 connects APP processing and mitochondrial dysfunction in AD. This provides a potential new therapeutic target for patients.

A Real-Time In Situ Demonstration of Direct and Indirect Transformation Pathways in CdTe Magic-Size Clusters at Room Temperature.

The transformations of colloidal semiconductor magic-size clusters (MSCs) are expected to occur with only discrete, step-wise redshifts in optical absorption. Here, we challenge this assumption presenting a novel, conceptually different transformation, for which the redshift is continuous. In the room-temperature transformation from CdTe MSC-448 to MSC-488 (designated by the peak wavelengths in nanometer), the redshift of absorption monitored in situ displays distinctly continuous and/or step-wise behavior. Based on conclusive evidence provided by real-time experiments, the former transformation is apparently direct and intra-cluster with a relatively large energy barrier. The latter transformation is indirect and assisted by MSC precursor compounds (PCs). The former transformation follows the latter often, being predominant at a relatively high temperature. The present findings encourage a reconsideration of the absorption redshift reported previously for transformations of binary II-VI MSCs, together with the pathway associated without the increase of cluster mass.

Transformation Pathways in Colloidal CdTeSe Magic-Size Clusters.

A rarely studied transformation in colloidal ternary magic-size clusters (MSCs) is addressed. We report the first observation of the transformation from ternary CdTeSe MSC-399 to MSC-422, which occurs at room temperature. These two MSC types display sharp optical absorption resonances at 399 and 422 nm, respectively, and are related in that they are quasi isomers, together with their counterpart precursor compounds (PCs). Binary CdTe and CdSe samples were prepared in the prenucleation stage also called the induction period (IP). After they were mixed and placed in a mixture of toluene and octylamine, the transformation was found to take place and to be assisted by the addition of the CdSe IP sample. A binary IP sample contains corresponding binary PCs and monomers (Mo) and fragments (Fr). We argue that the transformation pathway is enabled by the corresponding ternary PCs, involving the substitution reaction, namely CdTeSe PC-399 + CdSe (Mo/Fr)-1 ⇒ CdTeSe PC-422 + CdSe (Mo/Fr)-2. The present study provides an in-depth understanding of the formation characteristics of the MSCs.

Manipulating Reaction Intermediates to Aqueous-Phase ZnSe Magic-Size Clusters and Quantum Dots at Room Temperature.

It is not resolved which model describes better the aqueous-phase nucleation and growth of semiconductor quantum dots (QDs), the classical one-step one or the nonclassical multi-step one. Here, we design a room-temperature reaction to trap reaction intermediates in the prenucleation stage of ZnSe QDs (as a model system). We show that the trapped intermediate can transform to magic-size clusters (MSCs) via intra-molecular reorganization and can fragment to enable the growth of QDs. The MSCs exhibit a sharp optical absorption peaking at 299 nm, labelled MSC-299. The intermediate, the precursor compound (PC-299) of MSC-299, is optically transparent at 299 nm and to longer wavelengths. This intermediate forms in various Zn and Se reaction systems. The present study provides unambiguous evidence that the nonclassical and classical pathways are both necessary to explain the nucleation and growth of aqueous-phase QDs, with the former pathway favored more by high reaction concentrations.

Reversible Transformations at Room Temperature among Three Types of CdTe Magic-Size Clusters.

We report the first observation of the reversible transformations that occur among three types of CdTe magic-size clusters (MSCs) in dispersion at room temperature and discuss our understanding of the transformation pathway. The reversible transformations were achieved with CdTe prenucleation stage samples, which were prepared with reactions of cadmium oleate [Cd(OA)2] and tri-n-octylphosphine telluride in 1-octadecene and were then dispersed in mixtures of toluene and a primary amine at room temperature. Three types of OA-passivated CdTe MSCs evolved, exhibiting sharp optical absorption singlets peaking at 371, 417, and 448 nm. The MSCs and their immediate precursor compounds (PCs; with no sharp optical absorption) are labeled by the MSC absorption peak wavelengths. The transformation between MSC-371 and MSC-417 has a distinct isosbestic point at ∼385 nm and that between MSC-417 and MSC-448 at ∼430 nm. Our findings suggest that these PC-enabled reversible transformations occur through a process of quasi-isomerization, transforming between PCs and their counterpart MSCs, combined with substitution reactions that cause transformation between the two involved PCs.

Attitudes and Behavior of Patients with Gynecologic Malignancy Towards Sexual Issues: a Single-institutional Survey.

To better understand patients' perspectives and preferences for sexual issues and to provide information to guide medical staff in delivering sexual health care, an anonymous, cross-sectional survey of inpatient gynecologic cancer patients was conducted from April 2017 to March 2018. The questionnaire consisted of three parts: basic information, a history of sexuality discussion, and eight preference questions. A total of 1192 patients were included, and the median age was 43 years. More than half of the patients had a junior high school education or less and low income. Of the patients, 46.2% agreed that, "Doctors should deal with patients' sexual issues," and 56.2% agreed that, "Doctors should raise the topic of sexual issues." While 69.1% of the patients were willing to raise the topic themselves if any sexual problem existed, 35.9% of the patients agreed, "It's not the right time to discuss sex due to my severe disease." Less than 30% of the patients thought that "There's no need to intervene because sex is private" and "I do not feel comfortable discussing sex." A total of 41.1% of the patients were interested in undertaking basic sexual health consultation. Multiple logistic regression analysis demonstrated the following predictive factors for a history of consultation: young age; good education; and agreement with the statements, "Doctors should raise the topic of sexual issues," "If any sexual problem exists, I will raise the topic," and "I have an interest in participating in sex-counseling activities." Patients were willing to discuss sexual issues and were interested in sexual health training. It is important to increase the medical staff awareness of the need to inquire about and address patients' sexual issues.