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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.

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Purpose:Contrary to adult force reserve strategies, it is not known whether adolescent females with less experience performing maximal voluntary contractions (MVC) have specific responses to a known or unknown fatigue endpoint. Methods:Using a counterbalanced random crossover design, fourteen inexperienced female adolescents completed three elbow flexor (EF) fatiguing protocols. Participants were randomly assigned to a control (informed they would perform 12 MVCs), unknown (not informed of the number of MVCs to be completed, but stopped after 12) or deception condition (instructed to complete 6 MVCs, however, after the sixth repetition performed another 6 MVCs). Before and during the interventions, EF impulse, force, and biceps brachii (BB) and triceps brachii (TB) electromyography (EMG) activity were recorded. Results: Participants exhibited decreases in impulse (10.9%; p < .05), force (7.5%; p = .001), BB (16.2%; p < .05) and TB (12.9%; p < .05) EMG activity between the pretest and the first repetition of all protocols. Knowledge of endpoint, or lack of it, did not change measures with the repeated MVCs. When informed about the final repetition, force remained depressed suggesting no physiological reserve. Conclusion:Adolescent females exhibited an anticipatory response to the task of performing repeated MVCs. A lack of change with knowledge of endpoint indicates that those lacking in MVC experience do not employ the same pacing strategies as in previous studies of participants with MVC experience.

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.

Roller massage (RM) has been reported to reduce pain associated with exercise-induced muscle soreness and increase range of motion without force or activation impairments. The objective was to examine RM effects on evoked pain and contractile properties. Twelve men received three sets of 30-s RM at a perceived discomfort level of 7/10 on a visual analogue scale on the ipsilateral (IPSI-R) stimulated plantar flexors (PF), contralateral PF (CONTRA-R), Sham (light rolling on stimulated PF), or Control. At pre-test, post-test, and 5-min post-test, they received evoked maximal twitch, tetanus, and 70% maximal tetanic stimulation, and performed a maximal voluntary isometric contraction (MVIC). Data analysis included perceived pain and contractile properties. The 70% tetanus illustrated significant 9–10% increases in pain perception with Sham and Control at post- and 5-min post-test, respectively (p

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.

We report on the fabrication of 5 × 7.5 cm2 CdTe photovoltaic module devices using two alternative routes. One which uses the conventional approach where laser scribing and active layer deposition steps are inter-mixed, and the other via the one-step-interconnection (OSI) process. OSI combines three laser processes with two inkjet processes, depositing insulating and conductive materials. This allows the series interconnection to occur after the deposition of all active layers reducing fabrication time, capital equipment cost and interconnect dead zone. Its suitability for the manufacture of CdTe mini-modules has previously been demonstrated but no direct comparison was made against the conventional process. The structural properties and performance of conventional vs. OSI processed CdTe modules are presented and show comparable performance using both approaches with the OSI showing considerable process simplification.

This article provides a brief introduction to various aspects of oral health care in children, with emphasis on the epidemiology, risk assessment, prevention, and treatment modalities for dental caries. In addition, barriers to dental care and the involvement of pediatricians in advocating for and providing preventive dental care for children are reviewed. Oral health care is one of the most prevalent unmet needs among infants, toddlers, and adolescents in the United States. Routine or preventive dental visits are important for early diagnosis, prevention, and treatment of oral diseases, and for establishing and maintaining good oral health and overall well-being.

The tau lepton lifetime is measured with the L3 detector at LEP using the complete data taken at centre-of-mass energies around the Z pole resulting in tau_tau = 293.2 +/- 2.0 (stat) +/- 1.5 (syst) fs. The comparison of this result with the muon lifetime supports lepton universality of the weak charged current at the level of six per mille. Assuming lepton universality, the value of the strong coupling constant, alpha_s is found to be alpha_s(m_tau^2) = 0.319 +/- 0.015(exp.) +/- 0.014 (theory). The tau lepton lifetime is measured with the L3 detector at LEP using the complete data taken at centre-of-mass energies around the Z pole resulting in τ τ =293.2 ± 2.0 (stat) ± 1.5 (syst) fs . The comparison of this result with the muon lifetime supports lepton universality of the weak charged current at the level of six per mille. Assuming lepton universality, the value of the strong coupling constant, α s is found to be α s ( m τ 2 ) = 0.319 ± 0.015 (exp) ± 0.014 (theory). The tau lepton lifetime is measured with the L3 detector at LEP using the complete data taken at centre-of-mass energies around the Z pole resulting in tau_tau = 293.2 +/- 2.0 (stat) +/- 1.5 (syst) fs. The comparison of this result with the muon lifetime supports lepton universality of the weak charged current at the level of six per mille. Assuming lepton universality, the value of the strong coupling constant, alpha_s is found to be alpha_s(m_tau^2) = 0.319 +/- 0.015(exp.) +/- 0.014 (theory).

Thirty-one horses competing in a 100 kilometre endurance ride had electrocardiograms recorded before and after the ride from which the heart score of each horse was calculated. Blood was also taken to determine the packed cell volume (PCV) and total plasma protein (TPP) before the ride, after 60 kilometres (mid-ride) and at completion of the ride. Statistical analysis of the heart scores showed that a faster group of horses had significantly higher heart scores than either a slower group or those eliminated due to inadequate recovery of heart rate. No horses developed electrocardiogram abnormalities as a result of the ride. Analysis of the results of PCV and TPP showed that horses became dehydrated during the ride. The faster group of horses had significantly higher PCV values and heart rates at both the mid-ride and end of ride sampling times. However, the TPP values indicated no significant differences in the amount of dehydration between the 2 groups.

Evidence for performance decrements following prolonged static stretching (SS) has led to a paradigm shift in stretching routines within a warm-up. Rather than SS, dynamic stretching (DS) and dynamic activity (DA) have replaced SS within warm-up routines. The objective of the present study was to compare the effect of differing lower limb SS durations (30 [SS30s], 60 [SS60s] or 120 s [SS120s] of SS per muscle group or no-stretch control) within a comprehensive warm-up protocol consisting of aerobic activity, DS and DA. Sixteen male participants completed the four stretching conditions in a randomized order, after a 5-min low-intensity (cycle) warm-up and before a DS/DA component on separate days. Tests included passive hip and knee ranges of motion (ROM), maximum voluntary knee extensor/flexor force, force produced at 100 ms (F100), vertical jump height and evoked knee extensor contractile properties. For hip flexion (hamstrings) ROM, SS120s provided the largest increase (5.6–11.7%) followed by SS60s (4.3–11.4%), control (4.4–10.6%) and SS30s (3.6–11.1%). For knee flexion (quadriceps) ROM, SS30s provided the largest increase (9.3–18.2%) followed by SS120s (6.5–16.3%), SS60s (7.2–15.2%) and control (6.3–15.2%). There were decreases in quadriceps F100 following SS in SS120s (29.6%) only. There were increases in vertical jump performance in the control (6.2%), SS60s (4.6%) and SS30s (3.3%). While 120 s SS per muscle increased ROM, even within a comprehensive warm-up routine, it also elicited notable performance decrements. However, moderate durations of SS were observed to improve ROM whilst either having negligible or beneficial (but not detrimental) effects on specific aspects of athletic performance.

III-V semiconductor heterostructures grown on GaSb and InAs substrates are widely used to produce high performance optoelectronic devices operating in the technologically important mid-infrared spectral range. However, these substrates are expensive, only available in small sizes and have low thermal conductivity. Integration of III-Vs onto silicon substrates offers the opportunity to overcome these shortcomings and opens the possibility of new applications in lab-on-chip MIR photonic integrated circuits. However, the unusual III-V/Si interface and large lattice mismatch presents challenges to epitaxial growth. Here, we report on novel techniques employed to grow high quality Sb-based optoelectronic devices on silicon using molecular beam epitaxy.

Individuals with PHACE syndrome (posterior fossa malformations, hemangiomas, arterial anomalies, cardiac defects, eye abnormalities, sternal cleft, and supraumbilical raphe syndrome) have reported dental abnormalities to their healthcare providers and in online forums, but dental involvement has not been comprehensively studied. A study was conducted at the third PHACE Family Conference, held in Milwaukee, Wisconsin, in July 2012. A pediatric dentist examined subjects at enrollment. Eighteen subjects were enrolled. The median age was 4.2 years (range 9 mos-9 yrs; 14 girls, 4 boys). Eleven of 18 patients had intraoral hemangiomas and five of these (50%) had hypomature enamel hypoplasia. None of the seven patients without intraoral hemangiomas had enamel hypoplasia. No other dental abnormalities were seen. Enamel hypoplasia may be a feature of PHACE syndrome when an intraoral hemangioma is present. Enamel hypoplasia increases the risk of caries, and clinicians should refer children with PHACE syndrome to a pediatric dentist by 1 year of age.

Semiconductor quantum dots (QDs) have been encapsulated in poly(methyl, methacrylate) (PMMA) to prepare luminescent down-shifting films. The concentration of the QDs within each film has been varied, up to a maximum of 240 µg/mm3 and the optical properties have been characterised in detail. The QD/PMMA films have been placed over thin-film CdS/CdTe photovoltaic devices and improvements to cell performance have been recorded via external quantum efficiency and current–voltage measurements. The best overall improvement to performance, compared to the uncoated device, was 1.7%. This was obtained with a QD density of 48 µg/mm3, while the largest improvement to short-wavelength photocurrent was 30.30%, with a QD density of 192 µg/mm3. To further explain these results laser beam induced current measurements were carried out using laser wavelengths of 405 and 658 nm on individual cells with and without QD/PMMA films attached.

Commercially available quantum dots have been encapsulated in a poly(methyl methacrylate) film and used as a luminescent downshifting layer on cadmium sulfide/cadmium telluride photovoltaic devices. Application of these films has resulted in a relative improvement to the short-circuit current of over 4% by I–V measurement, with a significant increase in the contribution of short-wavelength light resulting in 25% of the current available in this part of the spectrum being captured. The films have been shown to be highly scattering and the associated difficulties this provides to external quantum efficiency measurements have been discussed. A range of optical characterisation techniques, particularly laser beam induced current, have been used to probe the effect the films have on a cadmium sulfide/cadmium telluride device. An alternate methodology for performing external quantum efficiency measurements with the quantum dot films has been proposed.

We report the successful molecular-beam epitaxial growth of 10 stacked layers of GaSb/GaAs quantum rings using a new procedure. Exact control of the arsenic flux during capping helps to reduce the strong group-V As–Sb exchange reactions, enabling the rings to be capped at the same growth temperature (480 °C) without dissolution. X-ray diffraction and transmission electron microscopy indicate excellent structural quality and uniformity with no threading dislocations. This is due to the reduction in the average strain through the quantum-ring formation. The total ring density in the stacks is 1 × 1011 cm–2. An unusually long-wavelength quantum-ring photoluminescence peak of 1.3 μm is observed at low temperature, which is attributed to a reduction in the quantum-ring charging due to lower unintentional p-doping in the GaAs cap layer. The impact that this effect will have on future device designs in solar cells and lasers is also discussed.

Summary Commercially available semiconductor quantum dots have been encapsulated within a poly(methyl, methacrylate) polymer matrix to form a luminescent down-shifting layer. The films were deposited, via doctor blading on thin film CdTe structures. This paper demonstrates an average increase of 16% in the conversion of photons with energies greater than the window layer band gap (>2.7 eV), which would normally not produce photocurrent due to the filtering effect of the window layer. The films have been characterised using surface mapping laser beam induced current measurements (LBIC) and external quantum efficiency (EQE). While these initial results show an overall decrease in the current output from the device, the possible loss mechanisms are explored and discussed.

In a constant effort to capture effectively more of the spectral range from the sun, multi-junction cells are being investigated. In this context, the marriage of thin film and dye-sensitized solar cells (DSC) PV technologies may be able to offer greater efficiency whilst maintaining the benefits of each individual technology. DSC devices offer advantages in the nature of both the metal oxide photo-electrode and dye absorption bands, which can be tuned to vary the optical performance of this part of a tandem device, while CdTe cells absorb the majority of light above their band-gap in only a few microns of thickness. The key challenge is to assess the optical losses with the goal of reaching a net gain in photocurrent and consequently increased conversion efficiency. This study reports on the influence of optical losses from various parts of the stacked tandem structure using UV-VIS spectrometry and EQE measurements. A net gain in photocurrent was achieved from a model developed for the DSC/CdTe mechanically stacked tandem structure.

Cavanaugh, MT, Aboodarda, SJ, Hodgson, DD, and Behm, DG. Foam rolling of quadriceps decreases biceps femoris activation. J Strength Cond Res 31(8): 2238-2245, 2017-Foam rolling has been shown to increase range of motion without subsequent performance impairments of the rolled muscle, however, there are no studies examining rolling effects on antagonist muscles. The objective of this study was to determine whether foam rolling the hamstrings and/or quadriceps would affect hamstrings and quadriceps activation in men and women. Recreationally, active men (n = 10, 25 ± 4.6 years, 180.1 ± 4.4 cm, 86.5 ± 15.7 kg) and women (n = 8, 21.75 ± 3.2 years, 166.4 ± 8.8 cm, 58.9 ± 7.9 kg) had surface electromyographic activity analyzed in the dominant vastus lateralis (VL), vastus medialis (VM), and biceps femoris (BF) muscles on a single leg landing from a hurdle jump under 4 conditions. Conditions included rolling of the hamstrings, quadriceps, both muscle groups, and a control session. Biceps femoris activation significantly decreased after quadriceps foam rolling (F(1,16) = 7.45, p = 0.015, -8.9%). There were no significant changes in quadriceps activation after hamstrings foam rolling. This might be attributed to the significantly greater levels of perceived pain with quadriceps rolling applications (F(1,18) = 39.067, p < 0.001, 98.2%). There were no sex-based changes in activation after foam rolling for VL (F(6,30) = 1.31, p = 0.283), VM (F(6,30) = 1.203, p = 0.332), or BF (F(6,36) = 1.703, p = 0.199). Antagonist muscle activation may be altered after agonist foam rolling, however, it can be suggested that any changes in activation are likely a result of reciprocal inhibition due to increased agonist pain perception.

A determination of the partial width Γc̄ of the Z0 boson into charm quark pairs is presented, based on a total sample of 36 900 Z0 hadronic decays measured with the DELPHI detector at the LEP collider. The production rate of cc events is derived from the inclusive analysis of charged pions coming from the decay of charmed meson D*+-→D0π+ and D*-→D̄0π- where the π± is constrained by kinematics to have a low pT with respect to the jet axis. The probability to procedure these π± from D*± decay in cc events is taken to be 0.31±0.05 as measured at √S = 10.55 GeV. The measured relative partial width Γ∞/Γh = 0.162± 0.030(stat.) ± 0.050(syst.) is in good agreement with the standard model value of 0.171. Together with our previous measurement of the total hadronic width Γh this implies Γ∞ = 282 ± 53 (stat.) ± 88 (syst.) MeV., 0, SCOPUS: ar.j, info:eu-repo/semantics/published

Bose-Einstein correlation between pairs of like-sign charged particles produced in e+e- annihilations near the Z0 peak have been studied using data taken with the DELPHI detector at LEP. An enhancement is found in the production of pairs of identical pions of similar moments, with respect to a reference sample. Under the hypothesis that the pions are emitted by a spherically symmetrical source with gaussian density, the data indicate a radius of the source of r = 0.62±0.04(stat.)±0.20(syst.) fm. The large systematic uncertainty reflects the sensitivity of r to the choice of the reference sample, 0, info:eu-repo/semantics/published

Contrary to adult force reserve strategies, it is not known whether adolescent females with less experience performing maximal voluntary contractions (MVC) have specific responses to a known or unknown fatigue endpoint.Using a counterbalanced random crossover design, fourteen inexperienced female adolescents completed three elbow flexor (EF) fatiguing protocols. Participants were randomly assigned to a control (informed they would perform 12 MVCs), unknown (not informed of the number of MVCs to be completed, but stopped after 12) or deception condition (instructed to complete 6 MVCs, however, after the 6th repetition performed another 6 MVCs). Before and during the interventions, EF impulse, force, and biceps brachii (BB) and triceps brachii (TB) electromyography (EMG) activity were recorded.Participants exhibited decreases in impulse (10.9%; p0.05), force (7.5%; p=0.001), BB (16.2%; p0.05) and TB (12.9%; p0.05) EMG activity between the pre-test and the first repetition of all protocols. Knowledge of endpoint, or lack of it, did not change measures with the repeated MVCs. When informed about the final repetition, force remained depressed suggesting no physiological reserve.Adolescent females exhibited an anticipatory response to the task of performing repeated MVCs. A lack of change with knowledge of endpoint indicates that those lacking in MVC experience do not employ the same pacing strategies as in previous studies of participants with MVC experience.

During constant-power output (PO) exercise above lactate threshold (LT), pulmonary O2 uptake (V̇o2p) features a developing slow component (V̇o2pSC). This progressive increase in O2 cost of exercise is suggested to be related to the effects of muscle fatigue development. We hypothesized that peripheral muscle fatigue as assessed by contractile impairment would be associated with the V̇o2pSC. Eleven healthy men were recruited to perform four constant-PO tests at an intensity corresponding to ∼Δ60 (very heavy, VH) where Δ is 60% of the difference between LT and peak V̇o2p. The VH exercise was completed for each of 3, 8, 13, and 18 min (i.e., VH3, VH8, VH13, VH18) with each preceded by 3 min of cycling at 20 W. Peripheral muscle fatigue was assessed via pre- vs. postexercise measurements of quadriceps torque in response to brief trains of electrical stimulation delivered at low (10 Hz) and high (50 Hz) frequencies. During exercise, breath-by-breath V̇o2p was measured by mass spectrometry and volume turbine. The magnitude of V̇o2pSC increased ( P < 0.05) from 224 ± 81 ml/min at VH3 to 520 ± 119, 625 ± 134, and 678 ± 156 ml/min at VH8, VH13, and VH18, respectively. The ratio of the low-to-high frequency (10/50 Hz) response was reduced ( P < 0.05) at VH3 (−12 ± 9%) and further reduced ( P < 0.05) at VH8 (−25 ± 11%), VH13 (−42 ± 19%), and VH18 (−46 ± 16%), mirroring the temporal pattern of V̇o2pSC development. The reduction in 10/50 Hz ratio was correlated ( P < 0.001, r2 = 0.69) with V̇o2pSC amplitude. The temporal and quantitative association of decrements in muscle torque production and V̇o2pSC suggest a common physiological mechanism between skeletal muscle fatigue and loss of muscle efficiency.

This paper details the AM0 conversion efficiency of a metal–organic chemical vapor phase deposition thin-film cadmium telluride (CdTe) solar cell deposited onto a cerium-doped cover glass (100 μm). An AM0 best cell conversion efficiency of 12.4% (0.25-cm2 contact area) is reported. An AM0 mean efficiency of 12.1% over eight cells demonstrated good spatial uniformity. Excellent adhesion of the cell structure to the cover glass was observed with an adhesive strength of 38 MPa being measured before cohesive failure of the test adhesive. The device structure on cover glass was also subject to severe thermal shock cycling of +80 °C to −196 °C, showing no signs of delamination and no deterioration of the photovoltaic (PV) performance.

Charge-carrier confinement in nanoscale In-rich agglomerations within a lateral InGaAs quantum well (QW) formed from stacked submonolayers (SMLs) of InAs in GaAs is studied. Low-temperature photoluminescence (PL) and magneto-PL clearly demonstrate strong vertical and weak lateral confinement, yielding two-dimensional (2D) excitons. In contrast, high-temperature (400 K) magneto-PL reveals excited states that fit a Fock-Darwin spectrum, characteristic of a zero-dimensional (0D) system in a magnetic field. This paradox is resolved by concluding that the system is heterodimensional: the light electrons extend over several In-rich agglomerations and see only the lateral InGaAs QW, i.e., are 2D, while the heavier holes are confined within the In-rich agglomerations, i.e., are 0D. This description is supported by single-particle effective-mass and eight-band k⋅p calculations. We suggest that the heterodimensional nature of nanoscale SML inclusions is fundamental to the ability of respective optoelectronic devices to operate efficiently and at high speed.

To improve CdS/CdTe cell/module efficiencies, CdS window layer thinning is commonly applied despite the risk of increased pin-hole defects and shunting. An alternative approach is to widen the band gap of the window layer (2.42eV for CdS) via alloying, for example, by forming compositions of Cd1� xZnxS. In this study, the performance of Cd1� xZnxS/CdTe thin-film solar cells has been studied as a function ofx(from x=0 to 0.9), widening the window layer band gap up to and over 3.4eV. Optimum Cd1� xZnxS compositions were clearly identified to be around x=0.7, and limitations to the achievable photocurrent and conversion efficiencies have been addressed. Copyright © 2012 John Wiley & Sons, Ltd.

The aim of this study was to investigate the effect of near-infrared (NIR) photobiomodulation on the proliferation and glutathione levels in murine Hertwig's epithelial root sheath (HERS) cells after poisoning with vinblastine.Photobiomodulation has been shown to improve wound healing in a number of animal models. There have been no studies on the effect of photobiomodulation on cancer-related chemotherapy injury to the cells that initiate tooth root growth.Control groups consisted of murine HERS cells without vinblastine (VB-) and cells with vinblastine at 10, 20, and 30 ng/mL (VB10, VB20, and VB30). Experimental groups consisted of these same groups with light therapy (VB-L, VB10L, VB20L, and VB30L). The cells were exposed to vinblastine for 1 h. Photobiomodulation consisted of a 75-cm(2) gallium-aluminum-arsenide light-emitting diode (LED) array at an energy density of 12.8 J/cm(2), delivered with 50 mW/cm(2) power over 256 s.Vinblastine alone significantly decreased HERS cell proliferation and glutathione levels at all concentrations (VB10 [-55%, p 1.0 × 10(-8)]; VB20 [-72%, p 1.0 × 10(-9)]; VB30 [-80%, p 1.0 × 10(-10)]; and VB10 [-36%, p 0.0001]; VB20 [-49%, p 1.0 × 10(-6)]; VB30 [-53%, p 1.0 × 10(-7)] respectively). Photobiomodulation significantly increased cell proliferation at all levels of vinblastine exposure (VB10L [+50%, p 0.0001]; VB20L [+45%, p 0.05]; VB30 [+39%, p 0.05]) but not of the control (+22%, p = 0.063). The photobiomodulation significantly increased glutathione production in all concentrations of vinblastine except 20 ng/mL (VB10L [+39%, p = 0.007]; VB20L [+19%, p = 0.087]; VB30 [+14%, p = 0.025]) and the control (+12%, p = 0.13).Photobiomodulation demonstrated an improvement in proliferation and glutathione levels in vinblastine-poisoned murine HERS cells.

We present the results of an investigation into the growth of InGaSb/GaAs quantum dots (QDs) by molecular beam epitaxy using migration-enhanced epitaxy. Surface atomic force microscopy and cross-sectional transmission electron microscopy show that the QDs undergo a significant change in morphology upon capping with GaAs. A GaAs ‘cold capping’ technique was partly successful in preserving QD morphology during this process, but strong group V intermixing was still observed. Energy-dispersive x-ray spectroscopy reveals that the resulting nanostructures are small ‘core’ QDs surrounded by a highly intermixed disc. Temperature varying photoluminescence measurements indicate strong light emission from the QDs, with an emission wavelength of 1230 nm at room temperature. Nextnano 8x8 k.p calculations show good agreement with the PL results and indicate a low level of group-V intermixing in the core QD.

MEDLINE/PubMed and EMBASE.The review included papers published between January 1, 1990 and December 31, 2008. The primary outcome was to retrieve all literature containing original data on dental caries, periodontal disease and pre-cancer dental clearance protocols in cancer patients undergoing head and neck radiotherapy, chemotherapy or combined treatment modalities. Excluded studies included systematic and non-systematic reviews, microbiology studies, growth and development studies, organ transplant studies, studies eliciting dental complications through questionnaires, studies reporting data from previous publications, phase I and II trials, opinion papers, case reports, articles published before 1990, and publications from the 1990 National Cancer Institute Monographs, which were based on the 1989 National Institutes of Health Development Consensus Conference on the Oral Complications of Cancer Therapies.Each article was independently evaluated by two reviewers with pilot-tested collection forms customised for reviewing dental disease data. Dental caries was assessed by the presence (Y/N), DMFT/dmft (decayed, missing, and filled teeth: DMFT for permanent adult teeth and dmft signifying deciduous teeth), and DMFS/dmfs indexes (decayed, missing, and filled surfaces: DMFS for permanent adult teeth and dmfs signifying deciduous teeth), if available. In addition, periodontal health was assessed using the plaque and gingival indexes. Further data collected for each article such as type of study, blinding, presence of control group, scale validity, and sample size were used to determine quality outcomes utilised to determine the weighted prevalence of caries and dental infection.Sixty-four published papers between 1990 and 2008 were reviewed. The weighted overall prevalence of dental caries was 28.1%. The overall DMFT for patients who were post-antineoplastic therapy was 9.19 (n=457). The overall plaque index for patients who were post-antineoplastic therapy was 1.38 (n=189). The gingival index for patients who were post-chemotherapy was 1.02 (n=162). The weighted prevalence of dental infection/abscess during chemotherapy was reported in three studies and was 5.8%.Patients who were post-radiotherapy had the highest DMFT. The use of fluoride products and chlorhexidine rinses is beneficial in patients who are post-radiotherapy. There continues to be a lack of clinical studies on the extent and severity of dental disease that are associated with infectious complications during cancer therapy.