Cactus-Inspired Janus Membrane with a Conical Array of Wettability Gradient for Efficient Fog Collection.

Fog collection plays an important role in alleviating the global water shortage. Despite great progress in creating bionic surfaces to collect fog, water droplets still could adhere to the microscale hydrophilic region and reach the thermodynamic stable state before falling, which delays the transport of water and hinders the continuous fog collection. Inspired by lotus leaves and cactuses, we designed a Janus membrane that functions to both collect fog from the air and transport it to a certain region. The Janus membrane with opposite wettability contains conical microcolumns with a wettability gradient and hydrophilic copper mesh surface. The apexes of conical microcolumns are superhydrophobic and the rest are hydrophobic. The fog droplets were deposited, coalesced, and directionally transported to the bottom of the conical microcolumns. Then, the droplets unidirectionally passed through the membrane and flowed into the water film on the surface of the copper mesh. The asymmetric structural and wettability merits endow the Janus membrane with an improved fog collection of ∼7.05 g/cm2/h. The study is valuable for designing and developing fluid control equipment in fog collection, liquid manipulation, and microfluidics.

pH-Responsive Smart Wettability Surface with Dual Bactericidal and Releasing Properties.

Biomaterial-associated infections caused by pathogenic bacteria have important implications on human health. This study presents the design and preparation of a smart surface with pH-responsive wettability. The smart surface exhibited synergistic antibacterial function, with high liquid repellency against bacterial adhesion and highly effective bactericidal activity. The wettability of the surface can switch reversibly between superhydrophobicity and hydrophobicity in response to pH; this controls bacterial adhesion and release. Besides, the deposited silver nanoparticles of the surface were also responsible for bacterial inhibition. Benefiting from the excellent liquid repellency, the surface could highly resist bacterial adhesion after immersing in a bacterial suspension for 10 s (85%) and 1 h (71%). Adhered bacteria can be easily eliminated using deposited silver nanoparticles during the subsequent treatment of alkaline bacterial suspension, and the ratio of deactivated bacteria was above 75%. After the pH returned to neutral, the deactivated bacteria can be easily released from the surface. This antibacterial surface showed an improved bacterial removal efficiency of about 99%. The results shed light on future antibacterial applications of the smart surface combining both bactericidal and adhesion-resistant functionalities.

A controllable oil-triggered actuator with aligned microchannel design for implementing precise deformation.

Soft actuators with the integration of facile preparation, rapid actuation rate, sophisticated motions, and precise control over deformation for application in complex devices are still highly desirable. Inspired by the aligned structures of moisture responsive pineal scales, an oil-triggered Janus actuator composed of a smooth hydrophobic surface and a superhydrophobic surface with aligned microchannels by simple laser etching was fabricated successfully, which can deform into various desirable shapes and recover to the original shape when triggered by oil and ethanol molecules. The aligned microchannel design causes different oil spread distances in the longitudinal and transverse directions, resulting in orientation-controlled bending and twisting with large-scale displacement. By changing the orientations of the patterned microchannels, one-dimensional folding deformation, twisting, rolling curling and object-inspired architectures can be facilely programmed. The reversible oil-triggered actuator will inspire more attractive applications such as in vivo surgery, biomimetic devices, energy harvesting systems and soft robotics.

Janus Soft Actuators with On-Off Switchable Behaviors for Controllable Manipulation Driven by Oil.

Soft actuators have tremendous applications in diverse fields. Facile preparation, rapid actuation, and versatile actions are always pursued when developing new types of soft actuators. In this paper, we present a facile method integrating laser etching and mechanical cutting to prepare Janus actuators driven by oil. A Janus film with superhydrophobic and hydrophobic sides was fabricated successfully. By cutting the functional layer at the desired positions, a number of quintessential oil-driven soft devices were demonstrated. Furthermore, Janus actuators with surfaces of different wettabilities exhibited different swelling behaviors, and different media manifested different surface extensions; thus, these actuators are promising candidates for soft actuators and also realized on-off switchability between an oil/water mixture and ethanol. This study offers novel insight into the design of soft actuators, and this insight may be helpful for developing an oil-driven soft actuator that can be operated like a human finger to manipulate any object and extending stimuli-responsive applications for soft robotics.

Comparison of safety and effectiveness between laparoscopic mini-gastric bypass and laparoscopic sleeve gastrectomy: A meta-analysis and systematic review.

BACKGROUND: The laparoscopic mini-gastric bypass is a newly emerged surgical procedure in recent years. Owe to safe and simple process and effective outcomes, laparoscopic mini-gastric bypass has quickly become one of the most popular procedures in some countries. The safety and effectiveness of laparoscopic mini-gastric bypass versus laparoscopic sleeve gastrectomy remain unclear. METHODS: A systematic literature search was performed in PubMed, Embase, Cochrane library from inception to May 20, 2017. The methodological quality of Randomized Controlled Trials and non-Randomized Controlled Trials were, respectively, assessed by Cochrane Collaboration's tool for assessing risk of bias and Newcastle-Ottawa scale. The meta-analysis was performed by RevMan 5.3 software. RESULTS: Patients receiving mini-gastric bypass had a lot of advantageous indexes than patients receiving sleeve gastrectomy, such as higher 1-year EWL% (excess weight loss), higher 5-year EWL%, higher T2DM remission rate, higher hypertension remission rate, higher obstructive sleep apnea (OSA) remission rate, lower osteoarthritis remission rate, lower leakage rate, lower overall late complications rate, higher ulcer rate, lower gastroesophageal reflux disease (GERD) rate, shorter hospital stay and lower revision rate. No significant statistical difference was observed on overall early complications rate, bleed rate, vomiting rate, anemia rate, and operation time between mini-gastric bypass and sleeve gastrectomy. CONCLUSION: Mini-gastric bypass is a simpler, safer, and more effective bariatric procedure than laparoscopic sleeve gastrectomy. Due to the biased data, small sample size and short follow-up time, our results may be unreliable. Large sample and multicenter RCT is needed to compare the effectiveness and safety between mini-gastric bypass and sleeve gastrectomy. Future study should also focus on bile reflux, remnant gastric cancer, and long term effectiveness of mini-gastric bypass.

Achieving high strength and high ductility in magnesium alloy using hard-plate rolling (HPR) process.

Magnesium alloys are highly desirable for a wide range of lightweight structural components. However, rolling Mg alloys can be difficult due to their poor plasticity, and the strong texture yielded from rolling often results in poor plate forming ability, which limits their further engineering applications. Here we report a new hard-plate rolling (HPR) route which achieves a large reduction during a single rolling pass. The Mg-9Al-1Zn (AZ91) plates processed by HPR consist of coarse grains of 30-60 µm, exhibiting a typical basal texture, fine grains of 1-5 µm and ultrafine (sub) grains of 200-500 nm, both of the latter two having a weakened texture. More importantly, the HPR was efficient in gaining a simultaneous high strength and uniform ductility, i.e., ~371 MPa and ~23%, respectively. The superior properties should be mainly attributed to the cooperation effect of the multimodal grain structure and weakened texture, where the former facilitates a strong work hardening while the latter promotes the basal slip. The HPR methodology is facile and effective, and can avoid plate cracking that is prone to occur during conventional rolling processes. This strategy is applicable to hard-to-deform materials like Mg alloys, and thus has a promising prospect for industrial application.

Ethyl 2-phenyl-5,6-dihydro-pyrrolo-[2,1-a]isoquinoline-3-carboxyl-ate.

In the title compound, C(21)H(19)NO(2), the six-membered heterocycle assumes a screw-boat conformation. The phenyl ring is oriented with respect to the pyrrole ring at a dihedral angle of 64.76 (10)°. An intra-molecular C-H⋯O hydrogen bond helps to stabilize the mol-ecular structure. There are weak C-H⋯π inter-actions between inversion-related mol-ecules in the crystal.