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A series of Mg–Y–Zn alloys with varying long-period stacking ordered (LPSO) phase fractions were prepared through control of alloy content, heat-treatment, and single-pass extrusion. The effect of LPSO phase volume fraction and microstructure refinement on the hydrogen absorption/desorption properties of ball-milled powders prepared from the extruded alloys was experimentally assessed. The hydrogen absorption and desorption kinetics scaled with the LPSO phase volume fraction, though the results of this study suggest that the scaling is not linear. Variations in the LPSO phase fraction and alloy content did not alter the (de)hydrogenation equilibrium pressure, indicating there is no significant change in thermodynamics of hydrogenation. Hydrogen absorption experiments on thin foils made from the extruded Mg–Y–Zn alloy with a high LPSO phase fraction demonstrated that the LPSO structures decompose into Mg phase, lamellar Mg/Mg–Zn structures and YH2 particles at hydrogen partial pressures sufficient to form YH2. This study shows that the hydrogen absorption/desorption kinetics in the Mg–Y–Zn alloys can be controlled by tailoring the LPSO phases using conventional metallurgical techniques. Graphical Abstract

ULTRARAMTM is a novel floating-gate nonvolatile memory in which the oxide barrier of flash is replaced by a triple-barrier resonant tunneling structure comprising of multiple InAs/AlSb heterojunctions. The quality of the triple barrier resonant tunneling heterostructure of an ULTRARAMTM device in terms of interface sharpness and the presence of defects was analyzed by cross-sectional scanning tunneling microscopy. We observed two different types of defects: stacking faults originating in the layers below the triple barrier resonant tunneling structure and AlSb accumulations at the interface between the lower AlSb layer of the triple barrier resonant tunneling structure and the InGaAs channel. The InGaAs surface of a second sample was measured by atomic force microscopy in order to investigate whether its unevenness is caused by deposition of the AlSb layer or it is already present before the AlSb deposition process.

NEW FINDINGS What is the central question of this study? During exercise, there are fluctuations in conduit artery blood flow (BF) caused by both cardiac and muscle contraction-relaxation cycles. What is the optimal method to process Doppler ultrasound-measured BF for the purpose of characterizing the dynamic response of BF during step-transitions in exercise? What is the main finding and its importance? Continuous BF data were processed in relation to either cardiac or muscle contraction-relaxation cycles and computed based on 'binned' or 'rolling' averages over one, two or five consecutive cycles. Kinetics characterization revealed no data processing technique-specific differences in steady-state BF, but variability in the rapidity at which BF attained steady-state (i.e., mean response time) was observed. ABSTRACT The overall rate of blood flow (BF) adjustment (i.e., kinetics) from the onset of an exercise transition can be quantified by the mean response time (MRT). However, the BF response profile can be distorted during rhythmic, dynamic exercise consequent to variations caused by the cardiac cycle (HR) and the muscle contraction-relaxation (CR) cycle. We examined the extent to which distortions imposed by HR and CR cycles affected BF kinetics. Eight healthy, young men (27 (4) years; mean (SD)) performed transitions of alternate-leg knee-extension exercise from 3 W to either a moderate- (MOD) or heavy-intensity (HVY) power output. Femoral artery BF was continuously measured by Doppler ultrasound and averaged over one, two or five 'binned' (e.g., HR2b, etc.) or 'rolling' (e.g., CR5r, etc.) HR and CR cycles. Among analysis techniques, there were no differences for steady-state BF values at the 3 W baseline. In MOD, MRT using contraction-relaxation cycle (CR1) was smaller than most other analysis techniques. For both MOD and HVY, the 95% confidence interval for MRT was generally larger when using HR- compared to CR-related methods, and monoexponential fits based on 'rolling' averages (HR2r, HR5r, CR2r, CR5r) had a poorer ability to estimate the true end-exercise BF in HVY than in MOD. When modelling BF kinetics, we conclude that the CR1 method is a good option because of its ability to accurately estimate the 'data-determined' end-exercise BF value from the 'model-derived' response, maintain a relatively high density of data points during the transition and yield a relatively small 95% CI.

ULTRARAM is a III–V compound semiconductor memory concept that exploits quantum resonant tunneling to achieve nonvolatility at extremely low switching energy per unit area. Prototype devices are fabricated in a $2\times2$ memory array formation on GaAs substrates. The devices show 0/1 state contrast from program/erase (P/E) cycles with 2.5 V pulses of 500- $\mu \text{s}$ duration, a remarkable switching speed for a $20~ \mu \text{m}$ gate length. Memory retention is tested for $8\times 10^{4}$ s, whereby the 0/1 states show adequate contrast throughout, whilst performing $8\times 10^{4}$ readout operations. Further reliability is demonstrated via program-read-erase-read endurance cycling for $10^{6}$ cycles with 0/1 contrast. A half-voltage array architecture proposed in our previous work is experimentally realized, with an outstandingly small disturb rate over $10^{5}$ half-voltage cycles.

Non-local muscle fatigue (NLMF) studies have examined crossover impairments of maximal voluntary force output in non-exercised, contralateral muscles as well as comparing upper and lower limb muscles. Since prior studies primarily investigated contralateral muscles, the purpose of this study was to compare NLMF effects on elbow flexors (EF) and plantar flexors (PF) force and activation (electromyography: EMG). Secondly, possible differences when testing ipsilateral or contralateral muscles with a single or repeated isometric maximum voluntary contractions (MVC) were also investigated. Twelve participants (six males: (27.3 ± 2.5 years, 186.0 ± 2.2 cm, 91.0 ± 4.1 kg; six females: 23.0 ± 1.6 years, 168.2 ± 6.7 cm, 60.0 ± 4.3 kg) attended six randomized sessions where ipsilateral or contralateral PF or EF MVC force and EMG activity (root mean square) were tested following a dominant knee extensors (KE) fatigue intervention (2×100s MVC) or equivalent rest (control). Testing involving a single MVC (5s) was completed by the ipsilateral or contralateral PF or EF prior to and immediately post-interventions. One minute after the post-intervention single MVC, a 12×5s MVCs fatigue test was completed. Two-way repeated measures ANOVAs revealed that ipsilateral EF post-fatigue force was lower (-6.6%, p = 0.04, d = 0.18) than pre-fatigue with no significant changes in the contralateral or control conditions. EF demonstrated greater fatigue indexes for the ipsilateral (9.5%, p = 0.04, d = 0.75) and contralateral (20.3%, p < 0.01, d = 1.50) EF over the PF, respectively. There were no significant differences in PF force, EMG or EF EMG post-test or during the MVCs fatigue test. The results suggest that NLMF effects are side and muscle specific where prior KE fatigue could hinder subsequent ipsilateral upper body performance and thus is an important consideration for rehabilitation, recreation and athletic programs.

Wastewater treatment plants (WWTPs) are key components for the capture of microplastics (MPs) before they are released into natural waterways. Removal efficiencies as high as 99% may be achieved but sub-micron MPs as well as nanoplastics have been overlooked because of analytical limitations. Furthermore, short MP fibres are of concern because of their low capture rate as well as the lack of understanding of their influence on purification system efficiency. This study has investigated the impact of poly(ethylene terephthalate) (PET) short nanofibres on the performance of polyvinylidene fluoride (PVDF) ultrafiltration membranes during cross-flow operation. Model MP fibres with an average length of 10 ± 7 μm and a diameter of 142 ± 40 nm were prepared via a combination of electrospinning and fine cutting using a cryomicrotome. The manufactured MPs were added to both pure and synthetic domestic wastewater at a concentration of 1 mg.L

Funding for this study was provided by the European Research Council under the European Union's H2020/ERC grant agreement no. 679651 (ConFooBio) to N.B. The experimental game was derived from NonCropShare, which was produced with financial support from the CGIAR Research Program on Water, Land and Ecosystems (WLE) and the CGIAR Research Program on Policies, Institutions and Markets (PIM). A.B.D. is supported by a Leverhulme Trust Early Career Fellowship. 1. Conflicts between the objectives of agricultural production and conservation are becoming increasingly complex. Of vital importance to the success of conflict interventions is a detailed understanding of how stakeholders react to management interventions as well as the influence of interacting social and political factors. 2. Across Europe, goose populations have increased considerably, leading to widespread impacts on agriculture and significant conflicts between different stakeholder groups. We used a novel experimental game to understand farmer preferences regarding the design of goose conflict interventions in Scotland. We specifically examined how three alternative interventions (government financial support for scaring activities, subsidies and agglomeration payments that include bonus payments for adoption by neighbouring farms) affect farmer propensity to support goose conservation interests through reduced shooting and the provision of sacrificial crops. We also examined the links between within-game behaviour and real-life attributes and attitudes of farmers. 3. We found that all three interventions were conducive to pro-conservation behaviour in the games. The effects of all three interventions were stronger among farmers who had higher trust towards other community members. Agglomeration payments led to increased provision of sacrificial crops among farmers with negative attitudes towards the current allocation of goose finances in Scotland. Farmers with more positive attitudes towards wildlife tourism were more likely to provide more sacrificial crops, and less likely to shoot in the games. 4. Farmers' real-life traits had a statistically significant but marginal impact on the effectiveness of financial payments, such as the number of geese being shot on their own lands, remoteness and crop damage by geese. 5. These game results provide evidence for the potential of innovative financial instruments in conflict management and their interactions with social factors such as community trust, equity attitude and real-life shooting levels. Our study highlights the importance of socio-political elements in fostering mutually beneficial outcomes in conservation conflicts in addition to addressing material losses to wildlife. We also show how games can help in addressing conservation conflicts in a wide range of settings. Publisher PDF

The influence of the parent austenite deformation state on the intervariant boundary network (i.e., population, plane orientation, and connectivity) of a lath martensitic microstructure was investigated using conventional EBSD mapping and five-parameter boundary analysis approach along with quantification of boundary connectivity using homology metrics. The lath martensite largely revealed a bimodal misorientation angle distribution, closely matched with the Kurdjumov–Sachs (K–S) orientation relationship. The application of deformation significantly changed the distribution, gradually reducing the intensity of the 60° misorientation angle peak. This was largely ascribed to substructure development within the parent austenite upon deformation, which stimulates particular variant/s having a habit plane (011)α′ closely parallel to the primary (111)γ and/or secondary (1$$\overline{1 }$$ 1 ¯ 1)γ slip plane. The interaction of these variants eventually promoted specific intervariant boundaries (e.g., 60°/[111], 10.5°/[011], and 49.5°/[110]) at the expense of 60°/[011]. The application of deformation in the parent austenite did not change the intervariant boundary plane character distribution, which mostly exhibited an anisotropic character terminated on {110} planes because of the displacive nature of the martensitic transformation. However, the extent of anisotropy progressively decreased with increasing strain in the austenite prior to transformation. The grain boundary network connectivity was markedly altered due to the local variant selection induced by the deformation. Deformation in the austenite regime generally decreased the connectivity of boundaries having a {110} plane orientation. The intervariant boundaries with the {110} twist character also displayed a similar trend, though the connectivity of {110} tilt boundaries progressively enhanced with increasing strain. The former was closely matched with a decrease in the population of 60°/[110] intervariant boundaries with the strain. The current findings suggest that the intervariant boundary network of lath martensite can be manipulated through changes in the parent austenite deformation state which, in turn, can be used to enhance key final product properties such as toughness. Graphical abstract

ABSRACTBackgroundHumans take vitamin D supplements to reduce risk of vitamin D deficiency and reduce the risk of osteoporosis. However, it is unclear how dietary super-doses (10,000x greater than requirement) can affect vitamin D status in aged animals. Aged laying hens could be a model to compare with women in peri- or postmenopausal stages of life. The hens’ bone health is physiologically taxed from egg production and they are highly susceptible to osteoporosis.ObjectiveWe investigated dietary super-dose impacts of cholecalciferol (vitamin D3) on vitamin D status in aged laying hens in production.MethodsForty-eight 68 wk old Hy-Line Brown laying hens were individually housed in cages with eight hens per dietary treatment for eleven weeks. Hens were randomly assigned to one of six groups of dietary vitamin D3 supplementation and fed ad libitum. Supplementation levels were 400, 800, 7,400, 14,000, 20,000, and 36,000 IU D3/kg of feed. At termination of the study, all hens were euthanized and we collected tissue samples and their feces. Tissue calcium, plasma and egg yolk vitamin D metabolites, and gene expression levels were measured.ResultsWe observed that increasing dietary vitamin D3 increased plasma vitamin D3, 25-hydroxycholecalciferol, and 24,25-dihydroxycholecalciferol concentrations (p < 0.0001 for all 3 metabolites). Also, egg yolk vitamin D3 and 25-hydroxycholecalciferol showed a similar effect like plasma vitamin D metabolites (p < 0.0001 for both metabolites). We also observed super-dose fed hens had decreased kidney 24-hydroxylase expression (p = 0.0006).ConclusionsDietary super-doses of vitamin D3 led to greater plasma and egg yolk vitamin D levels to show that aged laying hens can deposit excess vitamin D in egg yolk. We suggest future research should explore how 24-hydroxylation mechanisms are affected by vitamin D supplementation. Further understanding of 24-hydroxylation can help ascertain ways to reduce risk of vitamin D toxicity.

ULTRARAM™ is a non-volatile memory with the potential to achieve fast, ultra-low-energy electron storage in a floating gate accessed through a triple-barrier resonant tunnelling heterostructure. Here we report the implementation of ULTRARAM™ on a Si substrate; a vital step towards cost-effective mass production. Sample growth was carried out using molecular beam epitaxy, by first depositing an AlSb nucleation layer to seed the growth of a GaSb buffer layer, followed by the III-V memory epilayers. Fabricated single-cell memories show clear 0/1 logic-state contrast after ≤10-ms duration program/erase pulses of ~2.5 V, a remarkably fast switching speed for 10- and 20-µm devices. Furthermore, the combination of low voltage and small device capacitance per unit area results in a switching energy that is orders of magnitude lower than dynamic random access memory and flash, for a given cell size. Extended testing of the devices revealed retention in excess of 1000 years and degradation-free endurance of over 107 program/erase cycles, exceeding very recent results for similar devices on GaAs substrates.

Aim British Paediatric surgery guidelines (2019) state ‘immediate surgery should be performed if testicular torsion is suspected’. However, imaging ‘may be considered for a small number of children under the guidance of a senior clinician in late presenters or in those with atypical features. This study reviewed current practice in our hospital. Method Boys aged 16 and under in 2017-2019 who underwent scrotal exploration for suspected testicular torsion were reviewed. Outcomes assessed were number having ultrasound prior to theatre, pathological findings, number who had an orchidectomy, and post-op complications. Additionally, all testicular ultrasounds in those aged under 16 were screened to establish how many were requested for possible or missed torsion. Results 46 patients underwent surgical exploration of which 18 had a confirmed torsion. Six patients had imaging prior to surgery, of which five suggested torsions and four of these were confirmed in theatre. 202 boys under 16 had a testicular ultrasound; 26 of these were for late presentation or those with atypical features of torsion. Three underwent scrotal exploration two of whom had reports suggestive of torsion which was confirmed on exploration. Conclusions Most testicular torsions occur around the age of puberty with no torsion identified in patients under 10. Ultrasound is a useful tool for identification of vascularity or alternative pathology in late or atypical presentations of torsion; but does not replace clinical judgement. Imaging may have prevented unnecessary exploration in 23 cases, although negative imaging did not always preclude exploration.

Purpose: This pilot study investigated the prevalence of Molar-Incisor Hypomineralization (MIH) in third-grade school children in Milwaukee Wisconsin, USA. Methods: A convenience sample of third-grade school children in the Milwaukee Public School System (MPS) participated in the study. Calibrated examiners trained on the European Academy of Paediatric Dentistry (EAPD) MIH recommendations examined the children between December 1, 2014 and June 30, 2015. Children were examined at their schools using a flashlight and mirror after receiving consent from parents/caregivers and assent from each child. Findings were recorded onto a standardized form by one of five trained examiners. Summary statistics were calculated, and bivariate analysis were done to identify factors associated with MIH. Results: A total of 375 children (average age =8.66 years, range 7–12) were examined, 60% females and 41% Hispanics. Overall, 36 (9.6%) of the children demonstrated findings consistent with the diagnosis of MIH. Among the teeth with MIH defects, severe defects were higher in lower molars. There were no statistically significant differences between those with and without MIH by sex, race/ethnicity, and socioeconomic status in this study. Conclusion: The study revealed that 9.6% of the children examined were affected by MIH. Future studies should focus on statewide and/or nationwide surveys in the United States to ascertain the extent and severity of the condition.

The way in which research-based knowledge is used, interpreted and communicated by different actors can influence the dynamics of conservation conflicts. The conflict that occurs between grouse shooting interests and the conservation of birds of prey in Scotland is notoriously complex, involving multiple actors at multiple levels, and shaped by the values and world views of these actors. This paper explores how research-based knowledge is used in the debate by six key organisations, and looks to understand the drivers that may influence knowledge use and interpretation in this, and other, cases of conservation conflict. Research was used to both legitimise and reinforce certain world views, and to support associated political actions that would cause these to become reality. Actors offered divergent interpretations of the same piece of research, emphasising different findings and outcomes. Research-based knowledge was thus employed by actors to support or counter the ‘status quo’, and challenge other claims that clashed with their own values. Although the intention of such knowledge use is unclear, the selective reconstruction of research by actors could stem from, and reiterate, divergent value systems. This may pose significant challenges to conflict mitigation efforts; whilst some may look to research-based knowledge as the bringer of truth, its interpretation by different actors may exacerbate existing rifts between stakeholders; promoting polarisation of views. Mitigation strategies should be sensitive to this, and aim to improve the inclusiveness and transparency of the knowledge transfer process.

ULTRARAM™ is a III-V semiconductor memory technology which exploits resonant tunneling to allow ultra-low-energy memory logic switching (per unit area), whilst retaining non-volatility. Single-cell memories developed on GaAs substrates with a revised design and atomic-layer-deposition Al 2 O 3 gate dielectric demonstrate significant improvements compared to prior prototypes. Floating-gate (FG) memories with 20-μm gate length show 0/1 state contrast from 2.5-V program-read-erase-read (P/E) cycles with 500-μs pulse duration, which would scale to sub-ns switching speed at 20-nm node. Nonvolatility is confirmed by memory retention tests of 4×103 s with both 0 and 1 states completely invariant. Single cells demonstrate promising endurance results, undergoing 104 cycles without degradation. P/E cycling and disturbance tests are performed using half-voltages (±1.25 V), validating the high-density random access memory (RAM) architecture proposed previously. Finally, memory logic is retained after an equivalent of >105 P/E disturbances.

This work developed a well-bonded bcc/fcc bimetal interphase, which was produced by a two-step process involving diffusion bonding and conventional rolling. The high-quality interface maintained its integrity even at fracture. The earlier tensile instability in the core steel layer was constrained by the neighboring stable Cu layers on both sides, leading to extra strain hardening and consequently higher ductility. An increase in twin density or slip bands and shear deformation between the layers might be the primary causes for the observed hardening behaviors in the near-interface regions.

GaSb-based materials can be used to produce high performance photonic devices operating in the technologically important mid-infrared spectral range. Direct epitaxial growth of GaSb on silicon (Si) is an attractive method to reduce manufacturing costs and opens the possibility of new applications, such as lab-on-a-chip MIR photonic integrated circuits and monolithic integration of focal plane arrays (FPAs) with Si readout integrated circuits (ROICs). However, fundamental material dissimilarities, such as the large lattice mismatch, polar-nonpolar character of the III-V/Si interface and differences in thermal expansion coefficients lead to the formation of threading dislocations and antiphase domains, which effect the device performance. This work reports on the molecular beam epitaxial growth of high quality GaSb-based materials and devices onto Si. This was achieved using a novel growth procedure consisting of an efficient AlSb interfacial misfit array, a two-step GaSb growth temperature procedure and a series of dislocation filter superlattices, resulting in a low defect density, anti-phase domain free GaSb buffer layer on Si. A nBn barrier photodetector based on a type-II InAs/InAsSb superlattice was grown on top of the buffer layer. The device exhibited an extended 50 % cut-off wavelength at 5.40 μm at 200 K which moved to 5.9 μm at 300 K. A specific detectivity of 1.5 x1010 Jones was measured, corresponding in an external quantum efficiency of 25.6 % at 200 K.

Silicon photonics has emerged as the most promising technology for next-generation compact optoelectronic systems, but further development is still required to achieve efficient and reliable on-chip light sources. Direct epitaxial growth of antimonide-based compound semiconductor materials on silicon provides a pathway toward the monolithic integration of new, mid-infrared solid-state light sources and comprehensive photonic circuits on silicon platforms. Such devices have wide-ranging applications in environmental monitoring and medical diagnostics. This paper reports on the realization of a mid-infrared InAsSb light emitting diode directly integrated onto silicon using molecular beam epitaxy. The heteroepitaxial integration of the InAsSb p-i-n device onto silicon was achieved with the use of a novel, antiphase domain-free, GaSb-on-silicon buffer layer. The device exhibited efficient light emission at room temperature, peaking at around 4.5 μm, which corresponds well to the CO2 atmospheric absorption band. An output power of 6 μW and an external quantum efficiency of 0.011% was measured at 300 K. These results demonstrate mid-infrared III-V light emitting diodes can be directly grown on silicon, which is an essential step towards the realization of the next generation, on-chip integrated light sources.

Composite films comprised of silver nanoparticles (AgNPs) grown using a low-cost straightforward chemical bath based method have been deposited on glass microscope slides to investigate their potential as a sacrificial antibacterial coating. The as-deposited films have been characterised using scanning electron microscopy (SEM) and optical profilometry. These suggested that the films were relatively uniform in coverage. Chemical composition of the AgNP films has been studied by using X-ray photoelectron spectroscopy (XPS). The XPS analysis indicated that the Ag was in a metallic form able to sustain plasmon behaviour, and that low levels of residual nanoparticle precursors were present. Particle size was characterised using transmission electron microscopy (TEM) which showed an average particle size of 10.6 nm. The effectiveness of the films as an antibacterial coating was tested against Escherichia coli. The AgNP film was determined to be effective in the killing of E. coli cells over a 24 h period when compared to equivalent samples that contained no silver. Of particular note was that only minimal bacterial growth was detected over the first 12 h of testing, up to 78.6 times less than the control samples, suggesting the film is very efficient at slowing initial biofilm formation. The use of AgNP based films that have been synthesised using a novel low-cost, low-temperature and highly upscalable method is demonstrated as a promising solution for the deployment of silver as an effective sacrifical antimicrobial coating to counter the formation of potentially hazardous Gram negative biofilms.

OBJECTIVES To assess the association between dental sealant placement and subsequent restorative treatment of permanent first molars over time. METHODS We analysed Wisconsin Medicaid claims data from 2001 to 2009 for children aged 6-16 years. Children entered the study cohort at age 6 and were censored if Medicaid eligibility was lost for >31 days. A fixed effects analysis via a Cox proportional hazards model, stratified by individual, was used to estimate the time-averaged and time-dependent effects of sealant placement on dental treatment defined as any restorative, endodontic or surgical procedure. RESULTS A total of 185,262 children with permanent first molars who turned 6 years enrolled in Medicaid were examined. Sealant placement was higher for teeth #16 and 26 (5.42 and 5.46 per 100 person-years (100PY), versus 5.29 and 5.31/100PY for #36 and 46, respectively. The average rate for restorative treatments had the opposite pattern, with lower rate for teeth #16 and 26 (1.78 and 1.72/100PY) versus teeth #36 and 46 (2.14 and 2.12/100PY), respectively. In the fixed effects regression model, the hazard of dental treatment was substantially lower after sealant placement on a tooth, with time-averaged hazard ratio HR = 0.23 (95% CI 0.21-0.25, P

We report the controllable growth of GaAs quantum complexes in droplet molecular-beam epitaxy, and the optical properties of self-assembled Alalt;subagt;xalt;/subagt;Gaalt;subagt;1-xalt;/subagt;As quantum rings embedded in a superlattice. We found that Ga droplets on a GaAs substrate can retain their geometry up to a maximum temperature of 490alt;supagt;alt;/supagt;C during post-growth annealing, with an optimal temperature of 320alt;supagt;alt;/supagt;C for creating uniform and symmetric droplets. Through controlling only the crystallisation temperature under Asalt;subagt;4alt;/subagt; in the range of 450alt;supagt;alt;/supagt;C to 580alt;supagt;alt;/supagt;C, we can reliably control diffusion, adsorption and etching rates to produce various GaAs quantum complexes such as quantum dots, dot pairs and nanoholes. Alalt;subagt;xalt;/subagt;Gaalt;subagt;1-xalt;/subagt;As quantum rings are also realised within these temperatures via the adjustment of As beam equivalent pressure. We found that crystallisation using Asalt;subagt;2alt;/subagt; molecules in the place of Asalt;subagt;4alt;/subagt; creates smaller diameter quantum rings at higher density. The photoluminescence of Asalt;subagt;2alt;/subagt; grown Alalt;subagt;xalt;/subagt;Gaalt;subagt;1-xalt;/subagt;As quantum rings embedded in a superlattice shows a dominant emission from the quantum rings at elevated temperatures. This observation reveals the properties of the quantum ring carrier confinement and their potential application as efficient photon emitters.

PHACE(S) syndrome is a condition characterized by posterior fossa malformations, hemangiomas, arterial anomalies, cardiac defects, eye abnormalities, sternal cleft, and supraumbilical raphe. We present four children with PHACE(S) syndrome who have absence of or severe malformation of the roots of their permanent first molars (PFMs). Root abnormalities in the children's molars were bilateral and not restricted to the segments affected by cutaneous hemangioma. The reason for root abnormalities is unknown, but given the rarity of these findings in healthy children, it is likely an additional dental manifestation of PHACE syndrome. The absence of functional roots in the PFMs can result in significant consequences. Therefore, we recommend a panoramic dental radiograph during transitional dentition for children with PHACE syndrome to screen for dental root abnormalities.

On account of the recent increase in importance of biological and microbiological adhesion in industries such as healthcare and food manufacturing many researchers are now turning to the study of materials, wettability and adhesion to develop the technology within these industries further. This is highly significant as the stem cell industry alone, for example, is currently worth £3.5 million in the United Kingdom (UK) alone. This paper reviews the current state-of-the-art techniques used for surface treatment with regards to modulating biological adhesion including laser surface treatment, plasma treatment, micro/nano printing and lithography, specifically highlighting areas of interest for further consideration by the scientific community. What is more, this review discusses the advantages and disadvantages of the current techniques enabling the assessment of the most attractive means for modulating biological adhesion, taking into account cost effectiveness, complexity of equipment and capabilities for processing and analysis.

We define essential and strongly essential triangulations of 3-manifolds, and give four constructions using different tools (Heegaard splittings, hierarchies of Haken 3-manifolds, Epstein-Penner decompositions, and cut loci of Riemannian manifolds) to obtain triangulations with these properties under various hypotheses on the topology or geometry of the manifold. We also show that a semi-angle structure is a sufficient condition for a triangulation of a 3-manifold to be essential, and a strict angle structure is a sufficient condition for a triangulation to be strongly essential. Moreover, algorithms to test whether a triangulation of a 3-manifold is essential or strongly essential are given., Comment: 30 pages, 14 figures. Exposition improved

Direct integration of III–V semiconductor light sources on silicon is an essential step toward the development of portable, on-chip infrared sensor systems. Driven by the presence of characteristic molecular fingerprints in the mid-infrared (MIR) spectral region, such systems may have a wide range of applications in infrared imaging, gas sensing, and medical diagnostics. This paper reports on the integration of an InAs virtual substrate and high crystalline quality InAs/InAsSb multi-quantum wells on Si using a three-stage InAs/GaSb/Si buffer layer. It is shown that the InAs/GaSb interface demonstrates a strong dislocation filtering effect. A series of strained AlSb/InAs dislocation filter superlattices was also used, resulting in a low surface dislocation density of approximately 4 × 107 cm−2. The InAs/InAsSb wells exhibited a strong photoluminescence signal at elevated temperatures. Analysis of these results indicates that radiative recombination is the dominant recombination mechanism, making this structure promising for fabricating MIR Si-based sensor systems.

Mid-infrared (MIR) silicon photonics holds the potential for realizing next generation ultracompact spectroscopic systems for applications in gas sensing, defense, and medical diagnostics. The direct epitaxial growth of antimonide-based compound semiconductors on silicon provides a promising approach for extending the wavelength of silicon photonics to the longer infrared range. This paper reports on the fabrication of a high performance MIR photodetector directly grown onto silicon by molecular beam epitaxy. The device exhibited an extended cutoff wavelength at ∼5.5 μm and a dark current density of 1.4 × 10–2 A/cm2 under 100 mV reverse bias at 200 K. A responsivity of 0.88 A/W and a specific detectivity in the order of 1.5 × 1010 Jones was measured at 200 K under 100 mV reverse bias operation. These results were achieved through the development of an innovative structure which incorporates a type-II InAs/InAsSb superlattice-based barrier nBn photodetector grown on a GaSb-on-silicon buffer layer. The difficulties in growing GaSb directly on silicon were overcome using a novel growth procedure consisting of an efficient AlSb interfacial misfit array, a two-step growth temperature procedure and dislocation filters resulting in a low defect density, antiphase domain free GaSb epitaxial layer on silicon. This work demonstrates that complex superlattice-based MIR photodetectors can be directly integrated onto a Si platform, which provides a pathway toward the realization of new, high performance, large area focal plane arrays and mid-infrared integrated photonic circuits.

A 6-period GaAs/Al0.9Ga0.1As distributed Bragg reflector (DBR) has been grown and its optical properties have been both measured and simulated. Incremental improvements were made to the simulation, allowing it to account for internal consistency error, incorrect layer thicknesses, and absorption due to substrate doping to improve simulation accuracy. A compositional depth profile using secondary-ion mass spectrometry (SIMS) has been taken and shows that the Al fraction averages 88.0% ± 0.3%. It is found that the amplitude of the transmission is significantly affected by absorption in the n-doped GaAs substrate, even though the energy of the transmitted light is well below the GaAs band gap. The wavelength of the features in the transmission spectrum are mostly affected by DBR layer thicknesses. On the other hand, the transmission spectrum is found to be relatively tolerant to changes to Al fraction.

Purpose: This pilot study investigated the prevalence of Molar-Incisor Hypomineralization (MIH) in third-grade school children in Milwaukee Wisconsin, USA. Methods: A convenience sample of third-grade school children in the Milwaukee Public School System (MPS) participated in the study. Calibrated examiners trained on the European Academy of Paediatric Dentistry (EAPD) MIH recommendations examined the children between December 1, 2014 and June 30, 2015. Children were examined at their schools using a flashlight and mirror after receiving consent from parents/caregivers and assent from each child. Findings were recorded onto a standardized form by one of five trained examiners. Summary statistics were calculated, and bivariate analysis were done to identify factors associated with MIH. Results: A total of 375 children (average age =8.66 years, range 7–12) were examined, 60% females and 41% Hispanics. Overall, 36 (9.6%) of the children demonstrated findings consistent with the diagnosis of MIH. Among the teeth with MIH defects, severe defects were higher in lower molars. There were no statistically significant differences between those with and without MIH by sex, race/ethnicity, and socioeconomic status in this study. Conclusion: The study revealed that 9.6% of the children examined were affected by MIH. Future studies should focus on statewide and/or nationwide surveys in the United States to ascertain the extent and severity of the condition.

Conflict is currently one of the greatest challenges facing wildlife conservation. Whilst conflicts may first appear to concern wildlife, they are often embedded within wider debates surrounding land use, land ownership, and the governance of natural resources. Disputes over the impacts or management of a species therefore become symbols for conflicts that are fundamentally between the divergent interests and values of the people involved. NGOs representing the interests of local stakeholders can become actors within the conflict, often utilising publicly available platforms such as websites and social media in an attempt to influence over others and gain a dominant foothold in the debate. Here, we examined discourses of organisations in relation to a contentious and high-profile case of conflict in Scotland, that occurs between interests of raptor conservation and grouse moor management. News articles sourced from the websites of six organisations – identified as key voices in the debate – were subjected to discourse analysis. 36 storylines were drawn from common phrases and statements within the text. Storylines demonstrated a clear divide in the discourse; organisations differed not only in their portrayal of central issues, but also in their representation of other actors. Discourses were strategic; organisations interpreted the situation in ways that either supported their own interests and agendas, or damaged the image of opposing parties. We argue that discursive contestation at this level could be damaging to mitigation efforts – widening barriers between stakeholders and risking already fragile relationships. This in turn reduces the likelihood of consensus and impacts on successful decision-making and policy implementation. We conclude that conflict managers should be aware of the contestation between high-profile actors, and the ramifications this may have for conflict mitigation processes. An understanding of what constitutes these discourses should therefore be used as a foundation to improve dialogue and collaborative management.

Background Roller massagers are popular devices that are used to improve range of motion (ROM), enhance recovery from muscle soreness, and reduce pain under acute conditions. However, the effects of roller massage training and training frequency are unknown. Purpose The objective was to compare two different roller massage training frequencies on muscle performance. Study Design Randomized controlled intervention study. Methods Twenty-three recreationally active university students were randomly allocated to three groups: control (n=8;), rolling three (3/W; n=8;) and six (6/W; n=7) times per week for four weeks. The roller massage training consisted of unilateral, dominant limb, quadriceps and hamstrings rolling (4 sets x 30 seconds). Both legs of participants were tested pre- and post-training for active and passive hamstrings and quadriceps range of motion (ROM), electromyography (EMG) activity during a lunge movement, unilateral countermovement jumps (CMJ), as well as quadriceps and hamstrings maximum voluntary isometric contraction (MVIC) forces and electromechanical delay. Finally, they were tested for pain pressure threshold at middle and distal segments of their quadriceps and hamstrings. Results There were no significant training interactions for any measure with the exception that 3/W group exhibited 6.2% (p=0.03; Effect Size: 0.31) higher CMJ height from pre- (38.6 ± 7.1 cm) to post-testing (40.9 ± 8.1 cm) for the non-dominant limb. Conclusions Whereas the literature has demonstrated acute responses to roller massage, the results of the present study demonstrate no consistent significant training-induced changes. The absence of change may highlight a lack of muscle and myofascial morphological or semi-permanent neurophysiological changes with rolling. Levels of Evidence 2c.

In ramp-incremental cycling exercise, some individuals are capable of producing power output (PO) in excess of that produced at their limit of tolerance (LoT) whereas others cannot. This study sought to describe the 1) prevalence of a “power reserve” within a group of young men ( n = 21; mean ± SD: age 25 ± 4 yr; V̇o2max 45 ± 8 ml·kg−1·min−1); and 2) muscle fatigue characteristics of those with and without a power reserve. “Power reserve” (ΔPReserve) was determined as the difference between peak PO achieved during a ramp-incremental test to exhaustion and maximal, single-leg isokinetic dynamometer power determined within 45 s of completing the ramp-incremental test. Between-group differences in pre- vs. postexercise changes in voluntary and electrically stimulated single-leg muscle force production measures (maximal voluntary contraction torque, voluntary activation, maximal isotonic velocity and isokinetic power; 1-, 10-, 50-Hz torque; and 10/50-Hz ratio), V̇o2max, and constant-PO cycling time-to-exhaustion also were assessed. Frequency distribution analysis revealed a dichotomy in the prevalence of a power reserve within the sample resulting in two groups: 1) “No Reserve” (NRES: power reserve 15%; n = 11). At the LoT, all participants had achieved V̇o2max. Muscle fatigue was evident in both groups, although the NRES group had greater reductions ( P < 0.05) in 10-Hz peak torque (PT), 10/50 Hz ratio, and maximal velocity. Time to the LoT during the constant PO test was 22 ± 16% greater ( P < 0.05) in RES (116 ± 19 s; PO = 317 ± 52 W) than in NRES (90 ± 23 s; PO = 337 ± 71 W), despite similar ramp-incremental exercise durations and V̇o2max between groups. Compared with the RES group, the NRES group accrued greater peripheral muscle fatigue at the LoT, suggesting that the mechanisms contributing to exhaustion in a ramp-incremental protocol are not uniform. NEW & NOTEWORTHY This study demonstrates that the mechanisms associated with the limit of tolerance during ramp-incremental cycling exercise differ between those who are capable of generating power output in excess of that at exercise termination vs. those who are not. Those without a “power reserve” exhibit greater peripheral muscle fatigue and reduced muscle endurance, supporting the hypothesis that exhaustion occurs at a specific level of neuromuscular fatigue. In contrast, those with a power reserve likely are limited by other mechanisms.