Periodontal ligament regulatory role in experimental diabetic rat model of periodontium remodelling.

BACKGROUND: Diabetes, among multiple systemic harmful health issues, also may deteriorate normal regenerative and reparative functions of periodontium. The aim of this research was to study the role of periodontal ligament in tissue remodelling under the orthodontic appliance stimulation in two rat experimental models (healthy Wistar rats and Goto-Kakizaki, rodent model of non-obese type 2 diabetes). MATERIALS AND METHODS: Four groups of rats were defined: Wistar (WI; n = 8) and Goto-Kakizaki (GK; n = 8) control groups without orthodontic appliances, and Wistar (n = 16) and Goto-Kakizaki (n = 16) appliance groups with orthodontic appliances. After 42 days, rats were sacrificed and histopathology descriptive analysis about periodontal ligament and adjacent structures was performed as well as cellularity of periodontal ligament and Kappa curvature of tooth roots were measured. RESULTS: Goto-Kakizaki control rats showed statistically significantly higher cellularity in comparison with Wistar control rats (p < 0.001). Both applied groups (WI 44.63 ± 6.68; GK 79.58 ± 10.06) also showed statistically significantly higher cellularity (p < 0.001) in comparison with control groups (WI 34.48 ± 6.92; GK 45.31 ± 11.18). Applied groups (WI 0.197 ± 0.2; GK 0.126 ± 0.083) had statistically significant higher values of Kappa curvature in comparison with control groups (WI 0.023 ± 0.011; GK 0.037 ± 0.011) (WI appliance vs. WI control: p < 0.001; GK appliance vs. GK control: p < 0.05). Agitated periodontal ligament caused different degrees of cementoclasia and additionally dentinoclasia, altering the natural root curvature. CONCLUSIONS: Although not significantly different (WI and GK appliance groups) according to degree of molar roots odontoclasia, higher cellularity of agitated GK periodontal ligament could be influencing factor for, as previously reported, elevated osteoclast mobilization and possible prolonged periodontium reconstitution.

Colossal topological Hall effect at the transition between isolated and lattice-phase interfacial skyrmions.

The topological Hall effect is used extensively to study chiral spin textures in various materials. However, the factors controlling its magnitude in technologically-relevant thin films remain uncertain. Using variable-temperature magnetotransport and real-space magnetic imaging in a series of Ir/Fe/Co/Pt heterostructures, here we report that the chiral spin fluctuations at the phase boundary between isolated skyrmions and a disordered skyrmion lattice result in a power-law enhancement of the topological Hall resistivity by up to three orders of magnitude. Our work reveals the dominant role of skyrmion stability and configuration in determining the magnitude of the topological Hall effect.

Skyrmion-(Anti)Vortex Coupling in a Chiral Magnet-Superconductor Heterostructure.

We report experimental coupling of chiral magnetism and superconductivity in [IrFeCoPt]/Nb heterostructures. The stray field of skyrmions with radius ≈50 nm is sufficient to nucleate antivortices in a 25 nm Nb film, with unique signatures in the magnetization, critical current, and flux dynamics, corroborated via simulations. We also detect a thermally tunable Rashba-Edelstein exchange coupling in the isolated skyrmion phase. This realization of a strongly interacting skyrmion-(anti)vortex system opens a path toward controllable topological hybrid materials, unattainable to date.

Microwave resonances of magnetic skyrmions in thin film multilayers.

Non-collinear magnets exhibit a rich array of dynamic properties at microwave frequencies. They can host nanometre-scale topological textures known as skyrmions, whose spin resonances are expected to be highly sensitive to their local magnetic environment. Here, we report a magnetic resonance study of an [Ir/Fe/Co/Pt] multilayer hosting Néel skyrmions at room temperature. Experiments reveal two distinct resonances of the skyrmion phase during in-plane ac excitation, with frequencies between 6-12 GHz. Complementary micromagnetic simulations indicate that the net magnetic dipole moment rotates counterclockwise (CCW) during both resonances. The magnon probability distribution for the lower-frequency resonance is localised within isolated skyrmions, unlike the higher-frequency mode which principally originates from areas between skyrmions. However, the properties of both modes depend sensitively on the out-of-plane dipolar coupling, which is controlled via the ferromagnetic layer spacing in our heterostructures. The gyrations of stable isolated skyrmions reported in this room temperature study encourage the development of new material platforms and applications based on skyrmion resonances. Moreover, our material architecture enables the resonance spectra to be tuned, thus extending the functionality of such applications over a broadband frequency range.

A perpendicular field electromagnet with a 250 mm access bore.

We present a laboratory electromagnet capable of generating magnetic fields up to ±0.48 T, specifically designed as a perpendicular flux source for thin film samples in an ambient environment. The magnet features a 250 mm diameter clear access bore above the sample plane, thus offering compatibility with a wide variety of experimental apparatus. Despite its generous size, the magnet thermally dissipates less than 1 kW at maximum field. A shaped ferromagnetic core is used to amplify and homogenize the field B, leading to an estimated uniformity of ±1.5 mT (≲0.3%) in B within a 28 mm2 zone at maximum field. The sample stage is thermally regulated and isolated from the magnet, enabling temperature control with ±5 mK precision even at elevated magnetic fields.

An ultra-high-vacuum rotating sample manipulator with cryogenic cooling.

We report a homebuilt ultra-high-vacuum (UHV) rotating sample manipulator with cryogenic cooling. The sample holder is thermally anchored to a built-in cryogenic cold head through flexible copper beryllium strips, permitting continuous sample rotation. A similar contact mechanism is implemented for electrical wiring to the sample holder for thermometry. The apparatus thus enables continuous sample rotation at regulated cryogenic temperatures in a UHV environment. We discuss applications of this apparatus for cryogenic sputtering.

Resolving the taxonomic status of biocontrol agents belonging to the Aphidius eadyi species group (Hymenoptera: Braconidae: Aphidiinae): an integrative approach.

Species that belong to the Aphidius eadyi group have been used as biocontrol agents against Acyrthosiphon pisum worldwide. However, despite their extensive use, there are still gaps in our knowledge about their taxonomy and distribution. In this study, we employed an integrative taxonomic approach by combining genetic analyses (mtDNA COI barcoding) with standard morphological analyses and geometric morphometrics of forewing shape. We identified three species within the A. eadyi species group, viz., A. smithi, A. eadyi and A. banksae. Genetic separation of all three species was confirmed, with mean genetic distances between species ranging from 5 to 7.4%. The following morphological characters were determined as the most important for separating species of the A. eadyi group: number and shape of costulae on the anterolateral part of the petiole, shape of the central areola on the propodeum, and shape and venation of the forewings. The differences in wing shape of all three species were statistically significant, but with some overlapping. We identified A. banksae as a widely distributed pea aphid parasitoid, whose known range covers most of the western Palaearctic (from the UK to Israel). Aphidius banksae is diagnosed and redescribed.

Large-cell calcifying Sertoli cell tumour with macrocalcification in partially resected testis of young adult patient.

INTRODUCTION: There are less than 100 cases of Large-cell calcifying Sertoli cell tumour (LCCSCT) reported in English literature. Most of them are benign, bilateral and affect paediatric population. Malignant cases occur in older patients. LCCSCT is often associated with Carney complex or Peutz-Jaghers syndrome. We present the clinicopathological features of a young adult, with unilateral "stone-like" LCCSCT, without changes in hormonal status and no clinical characteristics of noted genetic disorders. CASE REPORT: A 24-year-old male presented with painless hardening of the right testis. There was no gynaecomastia, and serum levels of human chorionic gonadotropin and α-fetoprotein were normal. Ultrasound depicted hyperechogenic, clearly demarcated intratesticular lesion. Partial orchiectomy was performed. Macroscopically, tumour appeared as almost entirely calcified round mass, measuring 10 mm. Histopathological evaluation showed well-circumscribed, unencapsulated tumour composed of massive calcified geographic formations, surrounded with tumour cells. Neoplastic cells were large, polygonal, with abundant eosinophilic cytoplasm, and formed irregular cords, pseudo tubular structures, and nests in a fibrous and myxoid stroma, surrounded with lymphocytes. Other forms of calcification were also present: Needle-like deposits and lamellar, mulberry-like structures. There was no necrosis, mitotic activity and nuclear pleomorphism. Immunohistochemical study was positive for inhibin α and negative for Melan A, EMA, synaptophysin, chromogranin and AFP. DISCUSSION: LCCSCT needs to be differentiated from other, more frequent, sex cord stromal tumours. Clinical and genetical evaluation of these patients had to be performed, due to connection of LCCSCT with genetic abnormalities. In evidently benign cases, organ-sparing surgery should be considered for younger patients, followed by long term follow-up.

Tunable room-temperature magnetic skyrmions in Ir/Fe/Co/Pt multilayers.

Magnetic skyrmions are nanoscale topological spin structures offering great promise for next-generation information storage technologies. The recent discovery of sub-100-nm room-temperature (RT) skyrmions in several multilayer films has triggered vigorous efforts to modulate their physical properties for their use in devices. Here we present a tunable RT skyrmion platform based on multilayer stacks of Ir/Fe/Co/Pt, which we study using X-ray microscopy, magnetic force microscopy and Hall transport techniques. By varying the ferromagnetic layer composition, we can tailor the magnetic interactions governing skyrmion properties, thereby tuning their thermodynamic stability parameter by an order of magnitude. The skyrmions exhibit a smooth crossover between isolated (metastable) and disordered lattice configurations across samples, while their size and density can be tuned by factors of two and ten, respectively. We thus establish a platform for investigating functional sub-50-nm RT skyrmions, pointing towards the development of skyrmion-based memory devices.

Pseudogap and proximity effect in the Bi2Te3/Fe1+yTe interfacial superconductor.

In the interfacial superconductor Bi2Te3/Fe1+yTe, two dimensional superconductivity occurs in direct vicinity to the surface state of a topological insulator. If this state were to become involved in superconductivity, under certain conditions a topological superconducting state could be formed, which is of high interest due to the possibility of creating Majorana fermionic states. We report directional point-contact spectroscopy data on the novel Bi2Te3/Fe1+yTe interfacial superconductor for a Bi2Te3 thickness of 9 quintuple layers, bonded by van der Waals epitaxy to a Fe1+yTe film at an atomically sharp interface. Our data show highly unconventional superconductivity, which appears as complex as in the cuprate high temperature superconductors. A very large superconducting twin-gap structure is replaced by a pseudogap above ~12 K which persists up to 40 K. While the larger gap shows unconventional order parameter symmetry and is attributed to a thin FeTe layer in proximity to the interface, the smaller gap is associated with superconductivity induced via the proximity effect in the topological insulator Bi2Te3.

A disorder-enhanced quasi-one-dimensional superconductor.

A powerful approach to analysing quantum systems with dimensionality d>1 involves adding a weak coupling to an array of one-dimensional (1D) chains. The resultant quasi-1D (q1D) systems can exhibit long-range order at low temperature, but are heavily influenced by interactions and disorder due to their large anisotropies. Real q1D materials are therefore ideal candidates not only to provoke, test and refine theories of strongly correlated matter, but also to search for unusual emergent electronic phases. Here we report the unprecedented enhancement of a superconducting instability by disorder in single crystals of Na2-δMo6Se6, a q1D superconductor comprising MoSe chains weakly coupled by Na atoms. We argue that disorder-enhanced Coulomb pair-breaking (which usually destroys superconductivity) may be averted due to a screened long-range Coulomb repulsion intrinsic to disordered q1D materials. Our results illustrate the capability of disorder to tune and induce new correlated electron physics in low-dimensional materials.

Baerveldt tube implantation following failed deep sclerectomy versus repeat deep sclerectomy.

PURPOSE: To compare the surgical outcomes of repeat deep sclerectomy (DS) and the Baerveldt glaucoma implant (BGI) in eyes with failed primary deep sclerectomy. DESIGN: A retrospective comparative case-control study. METHODS: Fifty-eight eyes of 56 glaucoma patients with previously failed DS underwent BGI (group BGI) and 58 eyes of 55 patients underwent repeat DS (group DS) at a tertiary referral centre. Visual acuity, intraocular pressure (IOP), number of glaucoma medications, surgical failure rates and complication rates were compared between groups. Surgical failure was defined as loss of IOP control, loss of light perception, or need for further glaucoma surgery. RESULTS: Baseline demographics were similar between groups. Preoperatively, median IOP was lower in the DS than the BGI group (19 mmHg versus 21 mmHg, p = 0.10). Postoperatively at year 1, median IOP was significantly higher in the DS than BGI group (14 mmHg versus 11 mmHg, p = 0.02). There were no differences between the DS and BGI groups in mean number of medications preoperatively (2.3 versus 2.6) or postoperatively (1.3 versus 1.1). Complication rates were significantly higher in the DS group [41 % (n = 24) versus 14 % (n = 8); p = 0.01]. The failure rate at 1 year was higher in eyes with repeat DS than in eyes with BGI (30 vs. 21 %, respectively; p = 0.07). CONCLUSIONS: Baerveldt implants were more effective in lowering IOP and resulted in significantly fewer complications than repeat deep sclerectomy in eyes with previously failed deep sclerectomy.

The safety and feasibility of probiotics in children and adolescents undergoing hematopoietic cell transplantation.

Hematopoietic cell transplantation (HCT) has become a standard treatment for many adult and pediatric conditions. Emerging evidence suggests that perturbations in the microbiota diversity increase recipients' susceptibilities to gut-mediated conditions such as diarrhea, infection and acute GvHD. Probiotics preserve the microbiota and may minimize the risk of developing a gut-mediated condition; however, their safety has not been evaluated in the setting of HCT. We evaluated the safety and feasibility of the probiotic, Lactobacillus plantarum (LBP), in children and adolescents undergoing allogeneic HCT. Participants received once-daily supplementation with LBP beginning on day -8 or -7 and continued until day +14. Outcomes were compliance with daily administration and incidence of LBP bacteremia. Administration of LBP was feasible with 97% (30/31, 95% confidence interval (CI) 83-100%) of children receiving at least 50% of the probiotic dose (median 97%; range 50-100%). We did not observe any case of LBP bacteremia (0% (0/30) with 95% CI 0-12%). There were not any unexpected adverse events related to LBP. Our study provides preliminary evidence that administration of LBP is safe and feasible in children and adolescents undergoing HCT. Future steps include the conduct of an approved randomized, controlled trial through Children's Oncology Group.

A device for the application of uniaxial strain to single crystal samples for use in synchrotron radiation experiments.

We present the design, construction, and testing of a straining device compatible with many different synchrotron radiation techniques, in a wide range of experimental environments (including low temperature, high field and ultra-high vacuum). The device has been tested by X-ray diffraction on single crystal samples of quasi-one-dimensional Cs2Mo6Se6 and K2Mo6Se6, in which microscopic strains up to a Δc/c = 0.12% ± 0.01% change in the c lattice parameters have been achieved. We have also used the device in an inelastic X-ray scattering experiment, to probe the strain-dependent speed of sound ν along the c axis. A reduction Δν/ν of up to -3.8% was obtained at a strain of Δc/c = 0.25% in K2Mo6Se6.

Pseudophakic Retinal Detachment Surgery by 23 G Vitrectomy using Slit-Lamp and Non-Contact 90 D Lens.

BACKGROUND: The purpose of this study is to report the anatomic and functional results of primary 23 G vitrectomy using slit-lamp and non-contact 90 D lens for the treatment of pseudophakic rhegmatogenous retinal detachment. PATIENTS AND METHODS: Pseudophakic eyes were operated by 23 G vitrectomy using slit-lamp and non-contact 90 D lens, internal subretinal fluid drainage, cryopexy and internal gas tamponade. The preoperative and postoperative characteristics were analysed. Main outcome measures were anatomic success rates after initial surgical intervention and after reoperation for primary failures, visual outcome at the last follow-up visit, and complications. RESULTS: 46 pseudophakic eyes were included in this retrospective study (October 2013- January 2014). In 40 cases, sulfur hexafluoride 23% gastamponade was used, silicone oil in 6 cases (13%). The retina was reattached successfully after a single surgery in 44 eyes (96%). Recurrence of retinal detachment occurred in 2 eyes. Final anatomic reattachment was obtained in 100% after a second operation. Silicone oil was removed in all eyes. Visual acuity improved significantly from logMAR 0 (IQR 0-0.9) to logMAR 0 (IQR 0-0.2) (p<0.005). CONCLUSIONS: Primary 23 G vitrectomy using slit-lamp and non contact 90 D lens for the treatment of pseudophakic rhegmatogenous retinal detachment provides a high anatomic and functional success rate and is associated with few complications.

Long-range electronic reconstruction to a dxz,yz-dominated Fermi surface below the LaAlO3/SrTiO3 interface.

Low dimensionality, broken symmetry and easily-modulated carrier concentrations provoke novel electronic phase emergence at oxide interfaces. However, the spatial extent of such reconstructions - i.e. the interfacial "depth" - remains unclear. Examining LaAlO3/SrTiO3 heterostructures at previously unexplored carrier densities n(2D) ≥ 6.9 × 10(14) cm(-2), we observe a Shubnikov-de Haas effect for small in-plane fields, characteristic of an anisotropic 3D Fermi surface with preferential dxz,yz orbital occupancy extending over at least 100 nm perpendicular to the interface. Quantum oscillations from the 3D Fermi surface of bulk doped SrTiO3 emerge simultaneously at higher n(2D). We distinguish three areas in doped perovskite heterostructures: narrow (<20 nm) 2D interfaces housing superconductivity and/or other emergent phases, electronically isotropic regions far (>120 nm) from the interface and new intermediate zones where interfacial proximity renormalises the electronic structure relative to the bulk.

Molecular and morphological variability within the Aphidius colemani group with redescription of Aphidius platensis Brethes (Hymenoptera: Braconidae: Aphidiinae).

We have identified the following three taxa related to the Aphidius colemani species group, which are important biological control agents: Aphidius colemani, Aphidius transcaspicus and Aphidius platensis. Using partial sequences of the mitochondrial cytochrome oxidase subunit I (mtCOI) gene and geometric morphometric analysis of the forewing shape, we have explored the genetic structure and morphological variability of the A. colemani group from different aphid host/plant associations covering a wide distribution area. The topology of the maximum parsimony and maximum likelihood trees were identical with 98-100% bootstrap support, clustering A. colemani, A. platensis and A. transcaspicus into separate species. The distances among the taxa ranged from 2.2 to 4.7%, which is a common rate for the between-species divergence within the subfamily Aphidiinae. Differences in the shape of the forewing investigated within the biotypes of A. colemani group are congruent with their genetic diversification. Both A. platensis and A. colemani share a common host range pattern, and it would be interesting to estimate and compare the role of these two species in future biological control strategies against aphids of economic importance. Our results indicate that 'genetic screening' is a reliable approach for identification within the A. colemani group. The high variation in the wing shape among species, including a significant divergence in the wing shape among specimens that emerged from different hosts, makes the forewing shape and wing venation less reliable for species determination. Aphidius platensis is diagnostified and redescribed, and the key for the A. colemani group is presented.