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Understanding how terrestrial ecosystems would respond to future climate change can substantially contribute to scientific evaluation of the interactions between vegetation and climate. To reveal the future climate impacts might on the nature and magnitude of global vegetation, the spatiotemporal distribution and net primary productivity (NPP) of global terrestrial biomes and their dynamics in this century were quantitatively simulated and compared by using the improved Comprehensive and Sequential Classification System and the segmentation model. The 33 general circulation models under the four scenarios of Representative Concentration Pathways (RCPs) were utilized to simulate the future climate change. The multi-model ensemble results showed that at the global scale, the distribution of forests and deserts would expand by more than 2% and 4% over this century, respectively. By contrast, more than 11% of grassland regions would shrink. Despite the considerable differences in the simulated responses of the biomes, the poleward movement or expansion of temperate forest were prominent features across all the scenarios. Meanwhile, the terrestrial NPP was projected to increase by 7.44, 9.51, 9.46, and 12.02 Pg DW·a − 1 in 2070s relative to 1970s in the RCP2.6, RCP4.5, RCP6.0, and RCP8.5, respectively. The largest NPP decrease would occur in tundra & alpine steppe. NPP in the Tropical Zone, the North Temperate Zone, and the North Frigid Zone was estimated to increase in this century, whereas NPP in the South Temperate Zone was projected to decrease slightly across all scenarios. Overall, ecosystems in the mid-/high latitudes would be more vulnerable to future climate change in terms of distribution ranges and primary productivity despite the existing uncertainties. Some vegetation would benefit from the warmer and wetter climate. However, most of these plants would suffer and experience irreversible changes, particularly in the northern hemisphere. [ABSTRACT FROM AUTHOR]

Micro piezoresistive pressure sensor has become one of the most widely used microelectromechanical systems devices due to its high sensitivity, low cost and simple fabrication. For developing piezoresistive pressure sensor, one of the most important considerations is the configuration (structure) of the diaphragm. Although various types of diaphragm structure have been proposed, they are often designed intuitively, and thus to a large extent they depend on the designers' intuition and experience. This paper presents a systematic approach for designing diaphragm structures for piezoresistive pressure sensor by using topology optimization. The design problem is treated as a three dimensional topology optimization problem with design dependent loads in which the dependence is regarded due to transmissible loads. The objective is to minimize the mean compliance to achieve high linearity. Several geometrical constraints are developed to achieve high sensitivity. The design problem is solved by using the popular SIMP (Solid Isotropic Material With Penalization) method. A number of design examples are used to demonstrate the ability of the procedure to generate nonintuitive diaphragm structures. Solutions obtained from this procedure are compared with diaphragms with other configurations reported in the literature. [ABSTRACT FROM AUTHOR]

Invited for this month's cover picture is the group of Gunther Wittstock at Carl von Ossietzky University of Oldenburg. The cover picture represents the illustration of a single microscopic drop which is generated and directed to a reactive surface, where the liquid content is detected. The electrochemical detection is made possible by a phase transfer to a viscous ion‐conducting carrier liquid. Read the full text of the Research Article at10.1002/celc.202200004. [ABSTRACT FROM AUTHOR]

The insula is a region that integrates interoception and drug urges, but little is known about its role in behavioral addiction such as internet addiction. We investigated insula-based functional connectivity in participants with internet gaming disorder (IGD) and healthy controls (HC) using resting-state functional MRI. The right and left insula subregions (posterior, ventroanterior, and dorsoanterior) were used as seed regions in a connectivity analysis. Compared with the HC group, the IGD group showed decreased functional connectivity between left posterior insula and bilateral supplementary motor area and middle cingulated cortex, between right posterior insula and right superior frontal gyrus, and decreased functional integration between insular subregions. The finding of reduced functional connectivity between the interoception and the motor/executive control regions is interpreted to reflect reduced ability to inhibit motor responses to internet gaming or diminished executive control over craving for internet gaming in IGD. The results support the hypothesis that IGD is associated with altered insula-based network, similar to substance addiction such as smoking. [ABSTRACT FROM AUTHOR]

Compound machining (CM) compounded by arc machining and electrical discharge machining (EDM) milling is a new and fast processing method used to machine so-called “difficult-to-machine” materials. This method has an exciting maximum material removal rate that reaches 11,218 mm3/min with the relative electrode wear rate (REWR) of 1.54% when machining Inconel718. The electrode material is an important factor that affects the processing cost and quality of CM. Traditionally used electrode materials in arc machining and EDM, including pure tungsten (W), cerium tungsten (WCe20), copper (Cu), tungsten copper alloy (W80), and graphite (C), were used as electrode materials to process Inconel718. Experimental results show that tubular C is the best electrode material for CM. When tubular C is unavailable, WCe20 is the suitable electrode material for rough machining and W is a better choice in finish machining. Cu electrode is unsuitable for CM because of its low melting point. Results of this work provide guidance for selecting electrode materials for the industry application of efficient CM. [ABSTRACT FROM AUTHOR]

Electrical discharge machining (EDM) was developed over 70 years ago, but the knowledge of plasma channels that form during this process remain understudied. Therefore, this study systematically investigated the breakdown process and impedance characteristics of plasma channels through singe-pulse discharge experiments. The influence of discharge current and gap distance on the breakdown process and impedance characteristics of plasma channels was also analyzed. The results of this work can contribute to the existing body of knowledge of the physical nature of EDM. [ABSTRACT FROM AUTHOR]

Experiments of high-throughput electrical discharge milling (HTED milling) of WC-8%Co at 600-A peak current and 4766 mm/min material removal rate (MRR) using a 12-mm-external-diameter and 4-mm-internal-diameter tubular graphite electrode were conducted. The HTED milling process parameters, including peak current, electrode rotation speed, flushing pressure, and peak voltage, were studied to evaluate the effect on MRR, relative electrode wear rate, and diameter of overcut. The cross section, surface morphology, and microhardness of WC-8%Co for HTED milling were also investigated. Peak current has proven to be a critical factor for MRR. The MRR of HTED milling at peak current 600 A can be increased by ten times compared to that of HTED milling at peak current 100 A. Faster electrode rotation speed, larger flushing pressure, and higher peak voltage are essential to achieve low relative electrode wear rate (REWR) and high MRR. This study demonstrates that, using proper HTED milling process parameters and tubular graphite electrode, the HTED milling of WC-8%Co can be processed efficiently. [ABSTRACT FROM AUTHOR]