Despite unique properties of layered transition-metal dichalcogenide (TMD) nanosheets, there is still lack of a facile and general strategy for the preparation of TMD nanodots (NDs). Reported herein is the preparation of a series of TMD NDs, including TMD quantum dots (e.g. MoS2 , WS2 , ReS2 , TaS2 , MoSe2 and WSe2 ) and NbSe2 NDs, from their bulk crystals by using a combination of grinding and sonication techniques. These NDs could be easily separated from the N-methyl-2-pyrrolidone when post-treated with n-hexane and then chloroform. All the TMD NDs with sizes of less than 10 nm show a narrow size distribution with high dispersity in solution. As a proof-of-concept application, memory devices using TMD NDs, for example, MoSe2 , WS2 , or NbSe2 , mixed with polyvinylpyrrolidone as active layers, have been fabricated, which exhibit a nonvolatile write-once-read-many behavior. These high-quality TMD NDs should have various applications in optoelectronics, solar cells, catalysis, and biomedicine.

Compared with CsPbBr3 nanocrystals (NCs), the study of the structure and physical properties of Cs4PbBr6 and CsPb2Br5 NCs is not sufficient. In this paper, CsPbBr3, CsPb2Br5, and Cs4PbBr6 NCs were prepared by a hot-injection method using oleylamine (OAm) and oleic acid (OA) without adding other ligands. The evolution of phase composition, morphology, and photoluminescence (PL) property was investigated. It is found that rhombohedral Cs4PbBr6 was created at low temperature with low Pb/Cs ratios and short reaction time. The CsPbBr3 phase was then obtained with increasing Pb/Cs ratios at high temperature through the reaction of Cs4PbBr6 and PbBr2. The evolution of phase composition occurred with time to create CsPbBr3, CsPb2Br5, and Cs4PbBr6 NCs. For a Pb/Cs molar ratio of 3, CsPbBr3 was first obtained at 180 °C. However, the resulting sample is the CsPb2Br5 phase after 120 min. The excess PbBr2 is a key for such phase change because no similar phenomenon was observed in the case of molar ratio of Pb/Cs of 2. At low temperature (e.g., 140 and 160 °C), the rhombohedral Cs4PbBr6 phase was obtained and then reacted with PbBr2 to fabricate cubic CsPbBr3 nanosheets with sizes of several hundred nanometers. With changing phase composition, cubic, rod, and rhombohedral morphologies were created. The PL properties of the NCs depended strongly on the phase composition. As a result, CsPbBr3 NCs reveal highly bright PL with narrow and symmetrical PL spectra (PL peak at 520 nm). In contrast, no PL was observed for Cs4PbBr6 and CsPb2Br5 phases. The results provide a possibility to well control the growth for the application of cesium lead halide NCs.

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This experiment was conducted to study the effects of pantothenic acid on the growth performance, slaughter performance, lipid metabolism, and antioxidant function of one-to four-week-old Wulong geese and determine the appropriate supplemental level of pantothenic acid. A total of 360 one-day-old Wulong geese were randomly divided into 6 groups with 6 replicates per group and 10 geese (5 males and 5 females) per replicate. The geese in group Ⅰ (control group) were fed a basal diet, and the geese in groups Ⅱ to Ⅵ (experimental groups) were given the basal diet supplemented with 8, 15, 30, 60, and 120 mg/kg pantothenic acid, respectively. The experiment lasted for 4 weeks. Based on the results of unrelated comparative analysis, the body weight was the highest when the dietary pantothenic acid level was 27.57 mg/kg. When the dietary pantothenic acid level was 26.17 mg/kg, the average daily gain peaked. When the dietary pantothenic acid level was 15.50 mg/kg, the feed:gain ratio was the lowest. The percentage of abdominal fat in groups Ⅲ and Ⅳ was significantly lower than that in group Ⅰ (P < 0.05). The content of total cholesterol in serum in groups Ⅲ to Ⅴ was significantly lower than that in group Ⅰ (P < 0.05). The triglyceride content in groups Ⅲ and Ⅳ was significantly lower than that in group Ⅰ (P < 0.01). The high-density lipoprotein–cholesterol content in group Ⅳ was significantly higher than that in group Ⅰ (P < 0.05). The total antioxidant capacity of serum and liver in group Ⅳ was significantly higher than that in group Ⅰ (P < 0.05). The malondialdehyde content in the liver in groups Ⅲ and Ⅳ was significantly lower than that in group Ⅰ (P < 0.05). Glutathione peroxidase activity in the serum in group Ⅳ was significantly higher than that in group Ⅰ (P < 0.05). Glutathione peroxidase activity in the liver in groups Ⅳ and Ⅴ was significantly higher than that in group Ⅰ (P < 0.01). The addition of pantothenic acid in the diet of one-to four-week-old Wulong geese significantly affected the growth performance, slaughter performance, lipid metabolism, and antioxidant function of the geese. In terms of economic benefits, the optimal supplemental level of pantothenic acid in one-to four-week-old geese was 15.50 mg/kg.

PurposeOsteopontin (OPN) is a proinflammatory cytokine with diverse functions. Increased levels of OPN in vitreous fluid have been reported in patients with diabetic retinopathy (DR); however, studies on circulating OPN levels in DR are limited. We aim to examine the association of plasma OPN levels with the presence and severity of DR in a multiethnic cohort with type 2 diabetes mellitus (type 2 diabetes) in Singapore.MethodsPlasma levels of OPN were measured using enzyme-linked immunosorbent assay. Digital color fundus photographs were assessed for DR. DR severity was categorized into non-proliferative DR (NPDR) and proliferative DR (PDR). Gradable fundus photographs and OPN measurements for 443 patients were used for analysis. A logistic regression model was used to evaluate the association of OPN with DR.ResultsDR was diagnosed in 174 (39.3%) patients, including 132 (75.9%) with NPDR and 42 (24.1%) with PDR. The median of OPN was higher in the patients with DR (64.7 [49.7–89.5] ng/ml) than in the patients without DR (51.7 [38.9–66.9] ng/ml; p<0.001). After adjustment for clinical and biochemical factors, a 1-unit increase in nature logarithm (ln)-transformed OPN was associated with the presence of DR (2.770 [1.599–3.800], p<0.001). The area under the curve (AUC) increased statistically significantly after the addition of OPN (0.805[0.763–0.846] versus 0.825 [0.785–0.865], p=0.011). In the severity analyses, the median of OPN was statistically significantly higher in the patients with PDR (76.8 [55.0–103.6] ng/ml) than in the patients with NPDR (61.7 [47.7–87.3] ng/ml; p=0.017). After adjustment, the 1-unit increase in lnOPN remained associated with NPDR (2.673 [1.519–4.704], p=0.001) and PDR (3.389 [1.254–9.226], p=0.017), respectively (p-trend=0.001).ConclusionsPlasma OPN levels were associated with the presence and severity of DR in patients with type 2 diabetes, suggesting OPN may be useful as a potential biomarker for DR.