[Endovascular embolization for pulmonary artery pseudoaneurysms with massive hemoptysis]

Objective: To investigate the efficacy and safety of transcatheter embolization for the treatment of pulmonary artery pseudoaneurysms (PAPs) with massive hemoptysis via both arterial and venous access. Methods: The clinical data of 15 patients of pulmonary tuberculosis presenting with massive hemoptysis, who were confirmed by CTA/DSA with PAPs at the Second Affiliated Hospital of Hainan Medical University from January 2016 to February 2018, were retrospectively analyzed. The imaging presentation, technical and clinical success of endovascular treatment, and recurrence of hemoptysis within 1 year was recorded. Results: A total of 15 PAPs were involved. Fourteen PAPs were confirmed by pulmonary CTA and one by angiography. Six PAPs were visualized during bronchial artery angiography, 4 PAPs during pulmonary artery angiography, and 4 PAPs both. One PAP was not shown during catheter-directed angiography. Except for one patient who died of asphyxia due to severe hemoptysis undergoing embolization, hemoptysis relapse was achieved in 14 patients after endovascular treatment. During 12 months follow-up, one patient underwent surgical resection because of recurrent hemoptysis 2 weeks after embolization, and another patient with recurrence hemoptysis 3 months after embolization received repeated intervention and hemoptysis relapsed. Conclusion: Transcatheter embolization via dual access is effective and feasible for the treatment of PAPs with massive hemoptysis in patients with pulmonary tuberculosis, but still some risks.

A graphene-like membrane with an ultrahigh water flux for desalination

An ultrathin nanoporous membrane which combines high water permeability and high salt rejection is the core of ultrafiltration technology. Recently, we reported the synthesis of a chemically robust and nanoporous two-dimensional conjugated aromatic polymer (2D-CAP) membrane. Due to its array of highly regular sub-nanometer pores and channels, the ultrathin 2D-CAP membrane can be potentially used in desalination. Herein, we used molecular dynamics simulations to analyze the transmembrane hydrodynamics of mono- and multi-layer 2D-CAP membranes as a function of layer number. The energy barriers to water and ions across these membranes were calculated to evaluate the potential of 2D-CAP to function as the ultimate RO membrane. Our simulation results show that the bilayer CAP membrane exhibits superior ion rejection (100%) and a water flux (1172 L m^-2 h^-1 bar^-1) with a performance that is three orders of magnitude higher than the commercial reverse osmosis membrane, which is three times higher than the theoretically reported monolayer nanoporous MoS₂ membrane (the state-of-the-art membrane reported for desalination). In addition, the 2D-CAP bilayer membrane is highly resistant to swelling even at a high water flux. The monolayer 2D-CAP membrane shows good ion selectivity between monovalent and divalent ions.

Regulation of size and uniformity of In2O3 nanooctahedra

Rational regulation of the size and uniformity of nanoparticles has drawn great interests and shown widespread application, but this cannot be simply achieved by the vapor route. In this work, by adopting a chemical vapor deposition approach, the growth process was intricately regulated to guide the reagent supersaturation, and the large-scale growth of uniform-sized In2O3 nanooctahedra was realized. A one-time nucleation and synchronous growth mode controlled by the reagent supersaturation ratio is proposed to be responsible for the uniformity of size. Furthermore, a series of comparative experiments were conducted to study the size dependence on reaction duration, and temperature difference between the heating and depositing zones. This study demonstrates a feasible approach to prepare uniform-sized nanoparticles through precisely controlling the crystal growth process, and the developed growth strategy could be generalized to synthesize uniform-sized nanostructures of other material systems.

A temperature dependent screening tool for high throughput thermoelectric characterization of combinatorial films

Combinatorial metrology has evolved as a useful approach to rapidly determine the composition-structure-property relationships for solid solution systems in a far more efficient way than the traditional one composition at a time approach. The success of this method applied in thermoelectric (TE) research relies on screening tools to evaluate the TE properties for a combinatorial library. We report here on a thermoelectric screening tool capable of performing temperature dependent measurement of the Seebeck coefficient and electrical resistivity from 300 K to 800 K. The validity of the apparatus is demonstrated by screening the power factor of a filled skutterudite combinatorial film at room temperature and at elevated temperatures as well. The accuracy of the measurement is verified using the low temperature Seebeck coefficient Standard Reference Material (NIST SRM 3451) and a heavily doped SiGe specimen for high temperature comparison. Several important parameters, such as measurement atmosphere, film substrate, and probe configuration, are identified that directly affect the Seebeck coefficient measurement in this and other similar apparatus.

gamma-Tocotrienol modulates the paracrine secretion of VEGF induced by cobalt(II) chloride via ERK signaling pathway in gastric adenocarcinoma SGC-7901 cell line

Hypoxia is a common characteristic feature of solid tumors, and carcinoma cells are known to secrete many growth factors. These growth factors, such as vascular endothelial growth factor (VEGF), play a major role in the regulation of tumor angiogenesis and metastasis. In this study, the effect of gamma-tocotrienol, a natural product commonly found in palm oil and rice bran, on the accumulation of HIF-1alpha protein and the paracrine secretion of VEGF in human gastric adenocarcinoma SGC-7901 cell line induced by cobalt(II) chloride (as a hypoxia mimic) was investigated. These results showed that cobalt(II) chloride induced the high expression of VEGF in SGC-7901 cells at dose of 150 micromol/L for 24h. Both basal level and cobalt(II) chloride-induced HIF-1alpha protein accumulation and VEGF paracrine secretion were inhibited in SGC-7901 cells treated with gamma-tocotrienol at 60 micromol/L treatment for 24 h. U0126, a MEK1/2 inhibitor, decreased the expression of HIF-1alpha protein and the paracrine secretion of VEGF under normoxic and hypoxic conditions. In this study, gamma-tocotrienol also significantly inhibited the hypoxia-stimulated expression of phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2). The mechanism seems to involve in inhibiting hypoxia-mediated activation of p-ERK1/2, it leads to a marked decrease in hypoxia-induced HIF-1alpha protein accumulation and VEGF secretion. These data suggest that HIF-1alpha/VEGF could be a promising target for gamma-tocotrienol in an effective method of chemoprevention and chemotherapy in human gastric cancer.

Integrated centralized utility services to a chemical complex on Jurong Island, Singapore

SUT pioneered centralized utility services for the chemical industry on Jurong Island, which are cost-effective due to economies of scale, reliable due to inter-connection of satellite operations, and customer tailored for special requirements. The utility services range from the supply of steam and water, wastewater treatment, incineration, terminalling, service corridor to fire fighting. Among the services, water management achieves the complete cycle from wastewater treatment to effluent recycling.