Catalyst size dependent growth of Pd-catalyzed one-dimensional InAs nanostructures

In this study, Pd was used as catalyst to grow one-dimensional InAs nanostructures on GaAs (111)(B) substrates in order to explore the growth mechanism and the effect of non-gold catalysts in growing epitaxial III-V nanostructures. With detailed morphological, structural, and chemical characterizations using electron microscopy, coupled with analysis of the Pd-In binary phase diagram, it was found that size of Pd nanoparticles plays a key role in determining the growth mechanism of one-dimensional InAs nanostructures. (C) 2013 AIP Publishing LLC

Robust H

The robust H∞ control for spacecraft rendezvous with a noncooperative target is addressed in this paper. The relative motion of chaser and noncooperative target is firstly modeled as the uncertain system, which contains uncertain orbit parameter and mass. Then the H∞ performance and finite time performance are proposed, and a robust H∞ controller is developed to drive the chaser to rendezvous with the non-cooperative target in the presence of control input saturation, measurement error, and thrust error. The linear matrix inequality technology is used to derive the sufficient condition of the proposed controller. An illustrative example is finally provided to demonstrate the effectiveness of the controller

Facile Fabrication of Sandwich Structural Membrane With a Hydrogel Nanofibrous Mat as Inner Layer for Wound Dressing Application

A common problem existing in wound dressing is to integrate the properties of against water erosion while maintaining a high water-uptake capacity. To tackle this issue, we imbedded one layer of hydrogel nanofibrous mat into two hydrophobic nanofibrous mats, thereafter, the sandwich structural membrane (SSM) was obtained. Particularly, SSM is composed of three individual nanofibrous layers which were fabricated through sequential electrospinning technology, including two polyurethane/antibacterial agent layers, and one middle gelatin/rutin layer. The obtained SSM is characterized in terms of morphology, component, mechanical, and functional performance. In addition to the satisfactory antibacterial activity against Staphylococcus aureus and Escherichia coli, and antioxidant property upon scavenging DPPH free radicals, the obtained SSM also shows a desirable thermally regulated water vapor transmission rate. More importantly, such SSM can be mechanically stable and keep its intact morphology without appearance damage while showing a high water-absorption ratio. Therefore, the prepared sandwich structural membrane with hydrogel nanofibrous mat as inner layer can be expected as a novel wound dressing

The Protective Effect of Propofol Against Ischemia–Reperfusion Injury in the Interlobar Arteries: Reduction of Abnormal Cx43 Expression as a Possible Mechanism

Background/Aims: This experimental study aims to observe whether the protective effect of propofol against renal ischemia–reperfusion injury (IRI) in the rat interlobar artery occurs through altered expression of the gap junction protein connexin 43 (Cx43). Methods: This study randomly divided male Sprague Dawley (SD) rats into an untreated control group, a sham-operated control group (sham group), an ischemia–reperfusion group (IR group), a propofol group (propofol+IR group) and a fat emulsion group (Intralipid group). The ischemia/reperfusion model was prepared through resection of the right kidney and noninvasive arterial occlusion of the left kidney. Forty-five minutes after renal ischemia–reperfusion, an automatic biochemical analyzer was employed to measure blood urea nitrogen (BUN) and serum creatinine (SCr); changes in renal tissue pathology were observed using hematoxylin and eosin (HE) staining, and the vasomotor activity of the interlobar artery was detected using a pressure mechanogram technique. The protein expression of Cx43 in renal artery cross-sections was determined through western blotting. Results: The experimental study confirmed that the BUN and SCr of rats markedly increased after ischemia–reperfusion injury; additionally, we observed some coagulation necrosis and shedding of cells, some solidification of nuclear chromatin, degeneration of cytoplasmic vacuoles, high renal interstitial vascular congestion and obvious inflammatory cell infiltration, characterized by focal hemorrhages. Furthermore, the contraction activity of the renal interlobar artery greatly decreased, and the tension of the arteries in the renal lobe increased remarkably. After the gap junction blocking agents 2-APB and Gap27 were applied, the systolic velocity of blood vessels and the vascular contraction rate both decreased. In addition, the expression of Cx43 in kidney tissues increased markedly. The damage was more severe after 24 h of ischemic reperfusion than after only 4 h. However, after pretreatment with propofol, regardless of whether ischemia–reperfusion was applied for 4 h or 24 h, the previously increased expression of Cx43 decreased obviously, and all forms of renal damage were reversed. Conclusion: Our research suggests new ways for propofol to relieve ischemia–reperfusion injury by decreasing the abnormal expression of the gap junction protein Cx43. This study reveals a novel mechanism for the action of propofol against IRI, and we hope this finding will lead to new treatments for IRI

Microglia Are Indispensable for Synaptic Plasticity in the Spinal Dorsal Horn and Chronic Pain

Spinal long-term potentiation (LTP) at C-fiber synapses is hypothesized to underlie chronic pain. However, a causal link between spinal LTP and chronic pain is still lacking. Here, we report that high-frequency stimulation (HFS; 100 Hz, 10 V) of the mouse sciatic nerve reliably induces spinal LTP without causing nerve injury. LTP-inducible stimulation triggers chronic pain lasting for more than 35 days and increases the number of calcitonin gene-related peptide (CGRP) terminals in the spinal dorsal horn. The behavioral and morphological changes can be prevented by blocking NMDA receptors, ablating spinal microglia, or conditionally deleting microglial brain-derived neurotrophic factor (BDNF). HFS-induced spinal LTP, microglial activation, and upregulation of BDNF are inhibited by antibodies against colony-stimulating factor 1 (CSF-1). Together, our results show that microglial CSF1 and BDNF signaling are indispensable for spinal LTP and chronic pain. The microglia-dependent transition of synaptic potentiation to structural alterations in pain pathways may underlie pain chronicity

Ground calibration of Gamma-Ray Detectors of GECAM-C

As a new member of GECAM mission, GECAM-C (also named High Energy Burst Searcher, HEBS) was launched onboard the SATech-01 satellite on July 27th, 2022, which is capable to monitor gamma-ray transients from $\sim$ 6 keV to 6 MeV. As the main detector, there are 12 gamma-ray detectors (GRDs) equipped for GECAM-C. In order to verify the GECAM-C GRD detector performance and to validate the Monte Carlo simulations of detector response, comprehensive on-ground calibration experiments have been performed using X-ray beam and radioactive sources, including Energy-Channel relation, energy resolution, detection efficiency, SiPM voltage-gain relation and the non-uniformity of positional response. In this paper, the detailed calibration campaigns and data analysis results for GECAM-C GRDs are presented, demonstrating the excellent performance of GECAM-C GRD detectors.Comment: third versio

Calibration of the Timing Performance of GECAM-C

As a new member of the Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) after GECAM-A and GECAM-B, GECAM-C (originally called HEBS), which was launched on board the SATech-01 satellite on July 27, 2022, aims to monitor and localize X-ray and gamma-ray transients from $\sim$ 6 keV to 6 MeV. GECAM-C utilizes a similar design to GECAM but operates in a more complex orbital environment. In this work, we utilize the secondary particles simultaneously produced by the cosmic-ray events on orbit and recorded by multiple detectors, to calibrate the relative timing accuracy between all detectors of GECAM-C. We find the result is 0.1 $\mu \rm s$, which is the highest time resolution among all GRB detectors ever flown and very helpful in timing analyses such as minimum variable timescale and spectral lags, as well as in time delay localization. Besides, we calibrate the absolute time accuracy using the one-year Crab pulsar data observed by GECAM-C and Fermi/GBM, as well as GECAM-C and GECAM-B. The results are $2.02\pm 2.26\ \mu \rm s$ and $5.82\pm 3.59\ \mu \rm s$, respectively. Finally, we investigate the spectral lag between the different energy bands of Crab pulsar observed by GECAM and GBM, which is $\sim -0.2\ {\rm \mu s\ keV^{-1}}$.Comment: submitte

Look, the World is Watching How We Treat Migrants! The Making of the Anti-Trafficking Legislation during the Ma Administration

Employing the spiral model, this research analyses how anti-human trafficking legislation was promulgated during the Ma Ying-jeou (Ma Yingjiu) presidency. This research found that the gov- ernment of Taiwan was just as accountable for the violation of mi- grants’ human rights as the exploitive placement agencies and abusive employers. This research argues that, given its reliance on the United States for political and security support, Taiwan has made great ef- forts to improve its human rights records and meet US standards for protecting human rights. The reform was a result of multilevel inputs, including US pressure and collaboration between transnational and domestic advocacy groups. A major contribution of this research is to challenge the belief that human rights protection is intrinsic to dem- ocracy. In the same light, this research also cautions against Taiwan’s subscription to US norms since the reform was achieved at the cost of stereotyping trafficking victimhood, legitimising state surveillance, and further marginalising sex workers