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Inter-particle interactions play important roles in controlling the structures, dispersion state and chemo-physical properties of colloidal nanoparticles (NPs) in liquid media. In this work, we prepared palladium (Pd) NPs with an average diameter of ∼4.6 nm in situ inside the liquid cell, and investigated their coupled diffusion and aggregation behaviors through liquid cell transmission electron microscopy (LCTEM). Via analyzing the interaction energies and forces, we derived the effective working range for repulsive double layer interaction experimentally, a value larger than two times the Debye length, suggesting a different interaction behavior of sub-5 nm NPs from that of colloidal NPs in larger sizes. Our results provide insights for the interactions between colloidal ultrafine nanoparticles in solution and will also shed light on the precisely controlled assembly of colloidal nanocrystals for practical applications.

Melastomataceae have abundant morphological diversity with high economic and ornamental merit in Myrtales. The phylogenetic position of Myrtales is still contested. Here, we report the first chromosome-level genome assembly of Melastoma dodecandrum in Melastomataceae. The assembled genome size was 299.81 Mb with a contig N50 value of 3.00 Mb. Genome evolution analysis indicated that M. dodecandrum, Eucalyptus grandis and Punica granatum were clustered into a clade of Myrtales and formed a sister group with the ancestor of fabids and malvids. We found that M. dodecandrum experienced four whole-genome polyploidization events: the ancient event was shared with most eudicots, one event was shared with Myrtales, and the other two events were unique to M. dodecandrum. Moreover, we identified MADS-box genes and found that the AP1-like genes expanded, and AP3-like genes might have undergone subfunctionalization. We found that the SUAR63-like genes and AG-like genes showed different expression patterns in stamens, which may be associated with heteranthery. In addition, we found that LAZY1-like genes were involved in the negative regulation of stem branching development, which may be related to its creeping features. Our study sheds new light on the evolution of Melastomataceae and Myrtales, which provides a comprehensive genetic resource for future research.

Optimal treatment options for post-infectious bronchiolitis obliterans (PIBO) have not yet been established. The present study retrospectively analyzed the effect of budesonide, montelukast and azithromycin on treating PIBO in children

The development of ratiometric fluorescence sensing platforms with simple synthetic routes and good anti-interference capacities are of great importance for their further application. Herein, hyperbranched polyethylenimine passivated carbon dots (HPEI-CDs) with concentration-modulated dual-excitation fluorescence property were synthesized. At a low concentration, HPEI-CDs only showed one fluorescence center, while at a relatively high concentration, its excitation peak around 355 nm would split into two peaks. Energy level splitting and broadening were demonstrated to be the origin of such dual-excitation behavior. Based on the dual-excitation signals, HPEI-CDs could serve as a ratiometric sensor for the detection of Fe3+ in aqueous solution. The assay exhibited a wide linear response concentration range (2–360 μM) with a limit of detection of 0.47 μM. Significantly, benefiting from the high concentration of HPEI-CDs, the sensor showed good selectivity and excellent anti-interference capacity. In addition, this nanosensor was successfully applied for the detection of Fe3+ in real water samples with satisfactory recoveries.

To assess the efficacy and safety of alvimopan in conjunction with enhanced recovery strategy, compared with this strategy alone, in management of postoperative ileus in patients undergoing open abdominal surgery.Electronic databases were comprehensively searched for relevant randomized controlled trials. We were interested in doses of 6 and 12 mg. The efficacy end points included the time to recovery of full gastrointestinal (GI) function (a composite end point measured by the time to first toleration of solid food [SF] and the time to first passage of stool, GI-2), the recovery of upper (SF) or the lower (the time to first bowel movement, BM) GI function, and the length of hospital stay (the time to discharge order written). Safety end points included GI-related, non-GI-related, and serious adverse events. These parameters were all analyzed by RevMan 5.3 software.Nine randomized controlled trials involving 4075 patients were enrolled in this study. The pooled results showed that alvimopan significantly decreased the time to GI-2 recovery (6 mg, hazard ratio [HR] = 1.45, P 0.00001; 12 mg, HR = 1.59, P 0.00001), BM (6 mg, HR = 1.54, P 0.00001; 12 mg, HR = 1.74, P = 0.0002), and the time to discharge order written (6 mg, HR = 1.37, P 0.00001; 12 mg, HR = 1.34, P 0.00001) compared with the placebo group. However, SF was significantly reduced in 6 mg group (HR = 1.23, P = 0.008) rather than 12 mg group (HR = 1.14, 95% confidence interval 1.00, 1.30, P = 0.04). The incidence of some GI-related and serious adverse events were significantly lower in the alvimopan group than the placebo group, and the dose of 12 mg was superior to 6 mg in this regard.Alvimopan can accelerate recovery of GI function (especially for the lower GI tract), shorten the length of hospital stay, and reduce postoperative ileus-related morbidity without compromising opioid analgesia in an enhanced recovery setting.

Magnesium is one of the elements necessary for the body, is the man behind the body’s content of potassium ions within the cell are involved in a series of metabolic processes in vivo, including the formation of bone cells , acceleration of bone healing ability. Resulting from the good mechanical properties and biocompatibility, magnesium alloy is used in medical intervention material, but the high corrosion rate of magnesium alloys is the main drawback to their widespread use, especially in biomedical applications. There is a need for developing new coatings that provide simultaneously corrosion resistance and enhanced biocompatibility. In this work the medical magnesium alloy surface are dipped and coated with polylactic acid, so that obtain a dense uniform polylactic acid coating. And the corrosion resistance of the coating is studied in order to obtain controlled degradable and corrosion resisted magnesium alloy biological material. This paper mainly studies the influence of different concentrations of polylactic acid coating on AZ91D magnesium alloy corrosion resistance. The coated samples were immersed in Hank’s solution and the coating performance was studied by electrochemical impedance spectroscopy and scanning electron microscopy. This research is about the influence of the coating on the corrosion resistance of magnesium alloy through the open circuit potential, polarization curves, electrochemical impedance spectroscopy and Mott-Schottky. The results confirmed that the polylactic acid slow down the corrosion rate of AZ91D magnesium alloys in Hank’s solution. And along with the increase of poly lactic acid concentration, the corrosion resistance of magnesium alloys is improved. There is a wide variation of the corrosion morphology magnesium alloy AZ91D specimens after the surface modification using polylactic acid coating, compared with the unmodified.

Thermal stabilities and thermal decomposition mechanisms of amino-functionalized ionic liquid (IL) 1-aminoethyl-3-methylimidazolium bromide ([C2NH2MIM][Br]) and hydroxyl-functionalized IL 1-hydropropyl-3-methylimidazolium chloride ([C3OHMIM][Cl]) were investigated by thermogravimetric analysis (TGA), TG–mass spectroscopy (TG–MS), density functional theory (DFT), and nuclear magnetic resonance (NMR) spectrum. Results show that the [C2NH2MIM][Br] and [C3OHMIM][Cl] are stable up to 200 °C and 220 °C, respectively. Also, DFT calculation indicates that the thermal decomposition mechanisms of [C2NH2MIM][Br] and [C3OHMIM][Cl] are complicated, while bimolecular nucleophilic substitution (SN2) is the main reaction mechanism. TG–MS and NMR spectra further prove the mechanisms.

In this study, an amine-functionalized ionic liquid 1,2-dimethyl-(3-aminoethyl) imidazolium tetrafluoroborate [aEMMIM][BF 4 ] was designed and synthesized for better performance of CO 2 capture based on previous reports. Quantum chemical calculations had been used to investigate the interactions between CO 2 molecules and the as-synthesized ionic liquids. The molecular structures of the most stable conformation of [aEMMIM] cation and [aEMMIM][BF 4 ] were optimized at B3LYP/6-311++G (d, p) level. At the same time, we had performed CO 2 capture by [aEMMIM] cation. Compared with [aEMMIM][BF 4 ], the performance of [aEMMIM] cation on CO 2 capture was not as good as supposed. It was found that the anionic part of [aEMMIM][BF 4 ] played a non-neglectful role in CO 2 capture [aEMMIM][BF 4 ] was found to capture CO 2 with a 1:1 mol stoichiometry by quantum calculations due to the steric effect of the methyl group on C2 position of imidazolium ring. It was consistent with the experimental results. In order to understand the reaction mechanisms, we calculated the configuration variations on the reactant, intermediate, transition state and product, as well as energy barrier and vibration frequency changes in gas phase and using the conductor-like polarizable continuum model (CPCM) in water solution. The barrier height for [aEMMIM] and ([aEMMIM][BF 4 ]) capturing CO 2 is 47.25 (38.25) kcal/mol in gas phase and 38.92 (20.02) kcal/mol in water solution. These results indicate that the polarity of the solvent has played an important role on the reaction mechanisms. Frequency analysis indicates that the experimental results of the vibration frequencies are in better agreement with the scaled calculated values.

Taking military barracks wastewater treatment as an example, this paper presents a new concept design of a modified DEWATS system with both the horizontal subsurface constructed wetland and aquatic plants pond. Results show that this process in treating the military barracks area wastewater have many advantages such as low operation cost, simple operation and maintenance, and the effluent could meet the urban wastewater treatment plant pollutant discharge standard "(GB18919-2002) for first level Class A. It is suitable for the military barracks which have difficulty to be connected to centralized sewerage treatment system. At the same time, it can effectively improve the internal and surrounding water environment around the military barracks. This is a flexible wastewater treatment technology and can be replicated and applied for decentralized wastewater treatment.

There are both physical and chemical interactions between amine-functionalized ionic liquids (ILs) and CO2. A method to estimate the ratio between physical and chemical interactions based on NMR spectra was proposed. Results showed that 21% of [aEMMIM][BF4] interacted with CO2 chemically at 1:1 (CO2/IL) stoichiometry, leading to a 94% contribution to the solubility, whereas 79% of [aEMMIM][BF4] interacted with CO2 physically at 0.017:1 stoichiometry, leading to a 6% contribution. This method can be extended to other similar systems. Tethering high sterically substitute group at IL helps to obtain an equimolar CO2 absorption.

Three dimensional molecular dynamics simulation on the nanocutting of monocrystalline silicon is carried out to investigate the material deformation behaviors and atomic motion characteristics of the machined workpiece. A deformation criterion is developed to determine the material deformation and phase transformation behavior in the subsurface layer based on the single-atom potential energy variations. The results show that the machined chips suffer a complex phase transformation and eventually present an amorphous structure caused by the plastic deformation behavior. A polycrystalline structure is obtained on the machined surface. Both plastic and elastic deformation simultaneously takes place on the machined surface, and elastic deformation takes place under the machined surface. In order to further unveil the mechanism of nanocutting process, the displacements of all atoms are also simulated. The simulation results shows that different atomic motions occur in different regions in the workpiece, and the chips formations occur via extrusion.

Firstly, the superior performance and industrial application prospects of non-rotationally symmetric (NRS) optical surfaces are detailed. Secondly, those high precision machining processes to generate NRS optical surfaces are overviewed, it’s been stressed that fast tool servo (FTS) based diamond turning has been the most promising, cost-effective, and high precision machining process to generate NRS surfaces. Finally, the recent research progress in FTS based diamond turning of NRS optical surfaces is remarked, both the tool trajectory generation and the FTS actuation techniques are discussed, the limitations of the existing researches are disclosed, and then the academic and technological researches to be urgently carried out are suggested.

This paper discusses the design of a new type fast tool servo (FTS) for precision diamond turning. The FTS has two degrees. One of them is transversal along the Z axis of lathe and the other is rotation around the Y axis. Both of the two movements are driven by electromagnetic force. The moving assembly is designed to be parallel structure for guarantying both of the two movements has similar response frequency and maximum stroke. The output force of normal electromagnetic force generated by magnetic flux bias motor has been calculated. The design of transmission mechanism has been presented. The result of acceleration calculation shows that the FTS achieves acceleration up to about 650G in both directions of movement.

Although rare, burns suffered by neonates can be fatal. Many complex difficulties are faced during the management of burns in neonates because of the neonate's complex physiological and pathological changes. We compiled a retrospective review from the treatment of four burned neonates (including a premature neonate). All four neonates suffered bath-related burns in the hospital as a result of careless nursing when being bathed. The total body surface area burned ranged from 1 to 60% in these patients, and all survived the burn injury. All the patients were treated in the Burn Intensive Care Unit with close co-operation of burn surgeons and neonatologists. Based on our experience as well as a review of literature, management recommendations are proposed as the following: 1) prompt and aggressive fluid resuscitation, 2) early administration of oxygen and keeping the patient warm, 3) application of specific biological dressing and recombinant human growth hormone if necessary, 4) establishment of a multidisciplinary team, and 5) removal of necrosis tissue early and aggressively. Furthermore, a very important issue is also discussed, which is about the prevention of newborn burns in the neonate unit in developing countries.

A new iridoid glycoside, 6'-O-sinapoylgeniposide, was isolated from Gardenia jasminoides Ellis and its structure was elucidated on the basis of 1D and 2D NMR, HR-ESI-MS techniques.

To investigate the physical characteristic of Chinese Mandarin Monosyllabic word phonemes by the time-frequency analysis.Manufactured and study the three-dimensional speech chart which was on the basic of information of the time-frequency analysis in 40 monosyllabic words with the SigmaPlot 9.0 and Matlab 7.0 software.The mean value of basic frequency in 40 monosyllabic words was between 220 to 320 Hz area, and the mean value of four groups has significant difference by t-test. It is indicated by time-frequency analysis that the characteristics vary according to the tone of monosyllabic words. With the change of time, the various frequencies and its intensity of tone first remain basically unchanged, the curve is horizontal type; the different frequencies of tone second gradually tend to high-frequency direction, the graph is upward-type, additionally, the intensity of some tone drops little; the divers frequencies of tone third firstly deflect to low-frequency areas, then increasingly deviate to high-frequency direction of bias after maintaining a period of time, the figure is v-type, intensity changes are concave-shaped; The various frequencies of tone fourth deviate from high-frequency to low-frequency areas, and its intensity drops sharply, the graph is decreased type.Through time-frequency analysis and three-dimensional speech chart observation, we consider that the physical characteristic of Chinese Mandarin Monosyllabic word phonemes mainly reflects the frequencies and intensity change with time.

After establishing a murine model of aminoglycoside antibiotic (AmAn) induced ototoxicity, the sensitivity of AmAn induced ototoxicity in three murine strains and the effect of kanamycin on the expression of Na-K-2Cl cotransporter-1 (NKCC1) in stria vascularis were investigated.C57BL/6J, CBA/CaJ, NKCC1(+/-) mice (24 of each strain) were randomly divided into four experimental groups: A: kanamycin alone; B: kanamycin plus 2, 3-dihydroxybenzoate; C: 2, 3-dihydroxybenzoate alone; and D: control group. Mice were injected with kanamycin or/and 2, 3-dihydroxybenzoate twice daily for 14 days. Auditory brainstem response (ABR) was measured and morphology of cochlea delineated with succinate dehydrogenase staining. Expression of NKCC1 in stria vascularis was detected immunohistochemically.All three strains in groups A and B developed significant ABR threshold shifts (P0.01), which were accompanied by outer hair cell loss. NKCC1 expression in stria vascularis was the weakest in group A (A cf D, P0.01) and the strongest in groups C and D (P0.05). CBA/CaJ mice had the highest sensitivity to AmAn.Administration of kanamycin established AmAn induced ototoxicity. Kanamycin inhibited the expression of NKCC1 in stria vascularis. 2, 3-dihydroxybenzoate attenuated AmAn induced ototoxicity-possibly by enhancing the expression of NKCC1. Age related hearing loss did not show additional sensitivity to AmAn induced ototoxicity in murine model.