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While the mitigating effects of trees on shallow landslide occurrence are well recognised, the impact of landslides on tree community structure and tree-tree interactions have received much less research attention. The structures of tree communities before and after landslides were compared in a 25-ha subtropical forest plot. Tree-tree interactions were examined by analysing the pre- and post-landslide spatial point patterns of large (DBH ≥ 20 cm) and small (1 cm ≤ DBH < 20 cm) tree cohorts. In landslide scarps, 35 (34%) of 104 large trees and 467 (13%) of 3.072 small trees survived. Large (L) and small (S) tree cohorts were paired together for spatial analyses, including pre-landslide (PL) (LPL-SPL), surviving (S) (LS-SS), and missing (M) large-small tree paired cohorts (LM-SM). We randomly selected trees from the pre-landslide tree cohorts to create two virtual paired cohorts, the L34%-S13% and L66%-S87% paired cohorts, whose population sizes were identical to the field-observed LS-SS and LM-SM paired cohorts respectively, but with random spatial patterns. Post-landslide survival rates of trees increased monotonically with DBH. Large trees dislodged by landslides scarcely reduced small-tree survival. Evidence for this included: (i) the distance from small trees to the nearest large trees of the LM-SM paired cohort did not differ significantly from that of the virtual L66%-S87% paired cohort; (ii) survival rates of small trees near LM individuals did not differ significantly from those without large trees nearby. Surviving large trees had positive effects on the survival of small trees, indicated by: (i) the distance from small trees to the nearest large trees of the LS-SS paired cohort was significantly lower than that of the virtual L34%-S13% paired cohort; (ii) SS individuals clumped around LS individuals, whereas the virtual L34%-S13% spatial relationship was random. Large trees prevent landslide dislodgement of adjacent small trees through the nurse-plant effect. Our study suggests that landslide damage in sloping forests may be reduced simply by constantly maintaining a critical density of large trees.

Domain microstructures in single crystal lamellae of 88%Pb(Zn1/3Nb2/3)O3-12%PbTiO3 (cut from bulk using focused ion beam milling) have been mapped using both piezoresponse force microscopy and transmission electron microscopy. Dramatic changes from mottled microstructures typical of relaxors to larger scale domains typical of ferroelectrics have been noted. Stresses associated with substrate clamping are suspected as the cause for the transition from short- to long-range polar order, akin to effects induced by cation ordering achieved by thermal quenching. [ABSTRACT FROM AUTHOR]

Domain microstructures in single crystal lamellae of 88%Pb(Zn1/3Nb2/3)O3-12%PbTiO3 (cut from bulk using focused ion beam milling) have been mapped using both piezoresponse force microscopy and transmission electron microscopy. Dramatic changes from mottled microstructures typical of relaxors to larger scale domains typical of ferroelectrics have been noted. Stresses associated with substrate clamping are suspected as the cause for the transition from short- to long-range polar order, akin to effects induced by cation ordering achieved by thermal quenching. [ABSTRACT FROM AUTHOR]

Te-doped and ZnTe-doped diluted ZnSeTe samples were grown by using metal-organic chemical vapor deposition. The green lights emitted from these two samples in the photoluminescence (PL) measurement have different peak emission energies and can be attributed to different emission mechanisms. For the Te-doped sample, the PL emission band is excitation laser power independent, the lifetime of the PL emission is short, and the PL emission could be attributed to the emission originated from Te isoelectronic centers. For the ZnTe-doped sample, the energy of the green emission band is laser power dependent, the PL lifetime is much longer than the Te-doped sample, and the PL emission could be attributed to the emission from type-II ZnTe/ZnSe quantum dots. The results demonstrate that there are two different mechanisms responsible for the green PL emission in ZnSeTe system and our growth methods provide a way of selecting one of the two mechanisms for the green light emission in this system. [ABSTRACT FROM AUTHOR]

Background Carbapenems are traditionally reserved as the last line of defence for treatment of serious infections with multiresistant Gram-negative bacilli. Reports of K lebsiella pneumoniae carbapenemase ( KPC)-producing organisms have been emerging globally, but rare in Australasia to date. We describe an outbreak of KPC-2 producing K . pneumoniae at an Australian hospital. Methods After initial detection in October 2012, a retrospective review of patients with meropenem-resistant K . pneumoniae to June 2012, and ongoing prospective surveillance, was undertaken. Included patients were admitted to the hospital after June 2012 and had meropenem-resistant K . pneumoniae isolated from any site. Available isolates underwent detection of the KPC-2 gene by polymerase chain reaction and molecular typing was performed to determine genetic relatedness between isolates. Point-prevalence screening was performed on selected wards to detect asymptomatic carriage. Infection control procedures were implemented to contain the outbreak. Results Ten cases were identified in the initial cluster. Eight were localised to a single inpatient ward. Point-prevalence screening revealed one extra case. After temporary containment, re-emergence of KPC-producing isolates was observed post October 2013 with 18 further cases identified. Four K . pneumoniae isolates in the 2012 cluster and 16 from the 2013-2014 cluster were referred for further testing. All carried the KPC-2 beta-lactamase gene. The 2012 isolates were genetically similar to the 2014 isolates. Conclusion KPC-2 mediated resistance is an emerging threat in Australia. The re-emergence of KPC despite initial containment emphasises the need for constant vigilance in the microbiology laboratory and ongoing maintenance of infection control and antimicrobial stewardship activity. [ABSTRACT FROM AUTHOR]

Inspecific solid-state materials, under the right conditions,collections of magnetic dipoles are known to spontaneously form intoa variety of rather complex geometrical patterns, exemplified by vortexand skyrmion structures. While theoretically, similar patterns shouldbe expected to form from electrical dipoles, they have not been clearlyobserved to date: the need for continued experimental explorationis therefore clear. In this Letter we report the discovery of a rathercomplex domain arrangement that has spontaneously formed along theedges of a thin single crystal ferroelectric sheet, due to surface-relateddepolarizing fields. Polarization patterns are such that nanoscale“flux-closure” loops are nested within a larger mesoscaleflux closure object. Despite the orders of magnitude differences insize, the geometric forms of the dual-scale flux closure entitiesare rather similar. [ABSTRACT FROM AUTHOR]

In this study, the authors demonstrate the synthesis of various gold nanostructures through a one-step, green and complete bio-modulation approach. Nanoparticles were successfully synthesised by the addition of gold aqueous solution to fruit extracts, including orange, papaya, peach or lemon. The particles were of various shapes and sizes with high abundance, such as sphere, marigold, triangle and hexagon. The biocompatibility of the presented gold nanostructures was examined; haemolysis tests revealed a non-toxicity result in blood cell uptake of such gold nanostructures. This study opens the exciting possibility of synthesising various multi-shaped nanoparticles through a simple and green approach, as well as paving the way for future bio-applications. [ABSTRACT FROM AUTHOR]

Friction stir processing (FSP) was applied to produce aluminum-based in-situ composites from powder mixtures of Al-5 mol pct CeO2. A billet of powder mixtures was prepared using the conventional pressing and sintering route. The sintered billet was then subjected to multiple passages of FSP. This technique has combined the hot-working nature of FSP and the exothermic reaction between Al and CeO2. The reinforcing phases were identified as Al11Ce3 and δ *-Al2O3. The Al2O3 particles with an average size of ~10 nm are uniformly distributed in the aluminum matrix, which has an average grain size of approximately 390 to 500 nm. Both the sintering temperature and the tool traversing speed used in FSP have significant influence on the microstructure and mechanical properties of the composite. The composite produced by sintering at 833 K followed by FSP with a tool traversing speed of 30 mm/min possesses an enhanced modulus ( E = 109 GPa) and strength (ultimate tensile strength (UTS) = 488 MPa) as well as a tensile ductility of ~3 pct. [ABSTRACT FROM AUTHOR]

Objective. The important task for anaesthetists is to provide an adequate degree of neuromuscular block during surgical operations, so that it should not be difficult to antagonize at the end of surgery. Therefore, this study examined the application of a simple technique (i.e., fuzzy logic) to an almost ideal muscle relaxant (i.e., rocuronium) at general anaesthesia in order to control the system more easily, efficiently, intelligently and safely during an operation. Methods. The characteristics of neuromuscular blockade induced by rocuronium were studied in 10 ASA I or II adult patients anaesthetized with inhalational (i.e., isoflurane) anaesthesia. A Datex Relaxograph was used to monitor neuromuscular block. And, ulnar nerve was stimulated supramaximally with repeated train-of-four via surface electrodes at the wrist. Initially a notebook personal computer was linked to a Datex Relaxograph to monitor electromyogram (EMG) signals which had been pruned by a three-level hierarchical structure of filters in order to design a controller for administering muscle relaxants. Furthermore, a four-level hierarchical fuzzy logic controller using the fuzzy logic and rule of thumb concept has been incorporated into the system. TheStudent’s t test was used to compare the variance between the groups. p < 0.05 was considered significant. Results. The system achieved stable control of muscle relaxation with a mean T1% error of −0.19 (SD 0.66) % accommodating a range in mean infusion rate (MIR) of 0.21–0.49 mg· kg−1 · h−1. When these results were compared with our previous ones using the same hierarchical structure applied to mivacurium, less variation in the T1% error ( p < 0.05) but the same variation in infusion rate were observed. The controller activity of these two drugs showed no significant difference ( p> 0.5). However, the consistent medium coefficient variance (CV) of the MIR of both rocuronium (i.e., 36.13 (SD 9.35) %) and mivacurium (i.e., 34.03 (SD 10.76)%) indicated a good controller activity. Conclusions. The results showed that a hierarchical rule-based monitoring and fuzzy logic control architecture can provide stable control of neuromuscular block despite the considerable individual variation in neuromuscular block required among patients. Also, there was less variation in T1% error compared with that of previous study on mivacurium. Meanwhile, the consistent medium CV of the MIR of both rocuronium and mivacurium indicated a good controller activity which is able to withstand noise, diathermy effect, artifacts and surgical disturbances. [ABSTRACT FROM AUTHOR]

The extent to which notches inhibit axial switching of polarization in ferroelectric nanowires was investigated by monitoring the switching behavior of single crystal BaTiO3 wires before and after patterning triangular notches along their lengths. Static zero-field domain patterns suggested a strong domain-notch interaction, implying that notches should act as pinning sites for domain wall propagation. Surprisingly though, notches appeared to assist, rather than inhibit, polar switching. The origin of this effect was rationalized using finite element modeling of the electric field distribution along the notched wire; it was found that the air gap associated with the notch acted to enhance the local field, both in the air, and in the adjacent region of the ferroelectric. It seems that this local field enhancement outweighs any pinning interactions. [ABSTRACT FROM AUTHOR]

An attempt has been made to unequivocally identify the influence that inhomogeneous strain fields, surrounding point defects, have on the functional properties of thin film ferroelectrics. Single crystal thin film lamellae of BaTiO3 have been integrated into capacitor structures, and the functional differences between those annealed in oxygen and those annealed in nitrogen have been mapped. Key features, such as the change in the paraelectric-ferroelectric phase transition from first to second order were noted and found to be consistent with mean field modeling predictions for the effects of inhomogeneous strain. Switching characteristics appeared to be unaffected, suggesting that point defects have a low efficacy in domain wall pinning. [ABSTRACT FROM AUTHOR]

Manipulation of internal strain by an external light beam called photoelastic effect has been firmly established in ZnO nanorods. The underlying mechanism of this interesting phenomenon arises from the combination of the screening of internal electric field and converse piezoelectric effect. We demonstrate that the photoelastic effect is more pronounced in thinner nanorods due to a larger surface to volume ratio. In addition to giving a good evidence for the existence of photoelastic effect in semiconductor nanorods, our finding also provides an excellent possibility for the development of nanoscale optical modulators. [ABSTRACT FROM AUTHOR]

Ternary Zr–Cu–Ti system, especial with a high Ti content, is normally difficult to be fully vitrified. In this paper, we demonstrate that cosputtering can produce amorphous Zr–Cu–Ti thin films with an excessive Ti content even as high as 19%. Sub-Tg annealing of the film induces the formation of medium-range-ordered clusters and to raise the nanohardness by 35% to 6.6 GPa. The promising mechanical properties of the sub-Tg annealed Zr52Cu29Ti19 films offer great potential for microelectromechanical system applications. [ABSTRACT FROM AUTHOR]

Thin lamellae were cut from bulk single crystal BaTiO3 using a focused ion beam microscope. They were then removed and transferred onto single crystal MgO substrates, so that their functional properties could be measured independent of the original host bulk ferroelectric. The temperature dependence of the capacitance of these isolated single crystal films was found to be strongly bulklike, demonstrating a sharp Curie anomaly, as well as Curie–Weiss behavior. In addition, the sudden change in the remanent polarization as a function of temperature at TC was characteristic of a first order phase change. The work represents a dramatic improvement on that previously published by Saad et al. [J. Phys.: Condens. Matter 16, L451 (2004)], as critical shortcomings in the original specimen geometry, involving potential signal contributions from bulk BaTiO3, have now been obviated. That the functional properties of single crystal thin film lamellae are comparable to bulk, and not like those of conventionally deposited heterogeneous thin film systems, has therefore been confirmed. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate dioxin and dioxin-like polychlorinated biphenyls (PCBs) levels in human milk and their correlation with indicator PCBs concentrations and associated factors.Subjects were 36 pregnant mothers without clinical complications between 20 and 35 years. The participants answered a detailed questionnaire, including age, height, weight, parity, health, dietary habit and socioeconomic data. Breast milk was collected approximately two weeks after the delivery from December 1, 2000 to November 30, 2001. The samples were stored at -20°C refrigerator, centrifugated and separated, depolarized, and concentrated before the analyses. The extract was identified and quantified by high-resolution gas chromatograph with high-resolution mass spectrometry (HRGC/HRMS). Dioxins including polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), dioxin-like PCBs including non-ortho (IUPAC 77, 81, 126, 169) and mono-ortho (105, 114, 118, 123, 156, 157, 167, 189) congeners, and indicator PCBs (28, 52, 101, 138, 153, 180) were measured to determine the levels in human milk and the correlated factors.Total WHO-TEQ level of dioxin and dioxin-like PCB congeners from human milk was significantly lower (p < 0.001) in those aged > 29 year (10.5 pg-TEQ/g lipid, SD = 1.85) than in those aged 20-28 years (14.5 pg-TEQ/g lipid, SD = 2.39). The total TEQs level in our study was between the mean range from 10 to 35 pg-TEQ/g lipid in industrialized countries in the report from World Health Organization (WHO). For indicator PCBs, PCB 138, PCB153 and PCB 180 (three major indicator PCBs) consisted more than 97% of total concentrations. High correlation (r = 0.893, p < 0.01) was found between total TEQs and the total concentration of three major indicator PCBs in the smaller age group (20-28 year). For the older age group, the total concentration of three major indicator PCBs concentration was positively correlated with the total TEQ value (r = 0.542, p = 0.02). Total PCDD/F-TEQs was best predicted by three major indicator PCBs concentration (r = 0.678, p < 0.01) and total PCB-TEQs was best predicted by PCB 153 concentration (r = 0.891, p < 0.01). We found significantly higher dioxin-TEQs levels in human milk from the mothers eating sea fish more than once a week compared to those eating less ones (p = 0.041). Total TEQs level (dioxin/PCBs-TEQs) was found significant differences between the mothers education level (education level > high school) and yearly income (> $ 29000 dollars).Total WHO-TEQ level in the present study was found no higher than those in the WHO report. Total TEQs level can be best predicted by the total concentration of three major indicator PCBs in human milk exposure. We also found that total TEQs levels were positively associated with the consumption of sea fish, maternal education level, and yearly income. [ABSTRACT FROM AUTHOR]