Thin Patches Research Articles

AYURVEDIC MANAGEMENT OF PITYRIASIS ALBA (SIDHMA KUSTHA): A CASE STUDY

A skin rash that sometimes begins as a large spot on the chest, abdomen, hands or back followed by pattern of smaller lesions. Pityriasis refers to hypo pigmentation of skin. Pityriasis alba have symptoms like ill-defined patches, round and oval, often with mild scaling and sometimes with mild pruritus. They are most commonly noticeable in people with darker skin type. Clinical examination shows decreased melanin production in affected areas. Pityriasis alba is commonly caused by atrophic sebaceous glands, iron deficiency anemia, low level of serum copper and sun exposure. It occurs commonly in children aged 3-16 years with 90% of occurring in children younger than 12 years. An estimated 5 % of children in US may be affected. Studies have showed a higher prevalence in Egypt 18% and Mali 20%. There is no clear racial predominance of Pityriasis alba found. Duration of the rash is variable. According to Acharya Sushruta Sidhma Kustha is kapha pradhana vyadhi most commonly occurs in Urdhva kaya i.e., hasta, ura, mukha and lalata. Diseases start with mild kandu and result in formation of white thin patches without pain. A female patient of 24 years attended our OPD with complain of various circular, whitish, discoloured patches of irregular edges with moderate pruritis on bilateral upper limbs and neck root region anteriorly. Finally, on the basis of all sign and symptoms it was diagnosed as Sidhma Kustha. In treatment repeated Vamana karma and Virechana karma were done. Given treatment mainly pacifies kapha along with vata dosha.

Experimental Study of the Guided Wave Directivity Patterns of Thin Removable Magnetostrictive Patches.

The characteristics of removable magnetostrictive thin patches are investigated for the generation of guided waves in plates. The directivity patterns of SH, S0 and A0 modes have been measured in a thin metallic plate for different combinations of static and dynamic magnetic field directions. This used different coil geometries such as racetrack and spiral coils to generate the dynamic magnetic field, as well as separate biasing static magnetic fields from permanent magnets. This arrangement generated signals via both Lorentz and magnetostrictive forces, and the resultant emitted guided waves were studied for different dynamic and static magnetic field directions and magnitudes. It is demonstrated that different guided wave modes can be produced by controlling these parameters.

Rapid and Accurate Measurement of Polarization and Fading of Weak VHF Signals Obliquely Reflected From Sporadic-E Layers

In the E-region of the ionosphere, at heights between 90 and 130 km, thin patches of enhanced ionization occur intermittently. The electron density in these sporadic-E (Es) clouds can sometimes be so high that radio waves with frequencies up to 150 MHz are obliquely reflected. While this phenomenon is well known, the reflection mechanism itself is not well understood. To investigate this question, an experimental system has been developed for accurate polarimetric and fading measurements of 50 MHz radio waves obliquely reflected by mid-latitude Es layers. The overall sensitivity of the system is optimized by reducing environmental electromagnetic noise, giving the ability to observe weak, short-lived 50 MHz Es propagation events. The effect of the ground reflection on observed polarization is analyzed and the induced amplitude and phase biases are compensated. It is found that accurate measurements are only possible below the pseudo-Brewster angle. To demonstrate the effectiveness of the system, initial empirical results are presented which provide clear evidence of magneto-ionic double refraction.

Eclogite-Like Metagabbro of the Olkhon Terrane, West Baikal Area

Eclogite-like rocks of the Olkhon terrane correspond to two types according to the mode of occurrence and mineral compositions, although both types developed after the same type of gabbro of a single complex. The rocks of the first type are composed of garnet, clinopyroxene, pargasite (± scapolite, ± anorthite, ± spinel) and occur as thin veins or patches in the marginal parts of several small gabbro massifs of the Tonta Zone. The garnet is of almandine–pyrope–grossular composition and contains up to 40% of the pyrope end member. The rocks of the second type have been found in the Zamogoi Island in the Maloe More Strait. The island is composed of metasomatically altered gabbro cut by numerous granite and syenite veins. Carbonate and carbonate–silicate rocks compose dismembered veins and veinlets, as well as matrix embedding variably sized fragments of metasomatized gabbro and eclogite-like rocks in the southern part of the island. Based on the mode of occurrence and the presence of calcite–anorthite symplectite in some of the rocks, we suggest that the gabbro was penetrated by carbonate fluid or fluid–melt in a tectonic zone. The zone contains veins of garnet–clinopyroxene composition (varying from monomineralic garnetite to monomineralic pyroxenite) with minor pargasite, zoisite, anorthite, scapolite, and titanite. The garnet of Zamogoi Island has a grossular–almandine composition with a minor andradite concentration (about 10%). The compositions of minerals of the Zamogoi massif differ from the compositions of minerals in Tonta Zone, and the former are much more similar to skarn minerals.

Smart panel with piezoelectric patches connected to adaptive multi-resonant shunts for broadband vibration control

This paper presents a simulation study on the broadband control of flexural vibration of thin panels equipped with piezoelectric patches connected to adaptive multi-resonant shunts. The study considers the broadband flexural response of a thin rectangular aluminum panel exposed to a spatial and time stochastic excitation. The panel is equipped with thin square piezoelectric patches connect to shunts encompassing multiple parallel branches formed by RLC components connected in series. The capacitance C of each branch is kept fixed, whereas the inductance L and resistance R are adapted so as each branch maximizes the vibration power absorption from the resonant response of a specific flexural mode of the panel. The study proposes an on-line tuning approach, where the N-branches of each shunt are adapted sequentially to maximize the vibration absorption from the resonant responses of N neighbor flexural modes. The vibration power absorption of each branch is estimated from the electric power absorbed by the shunt. In this way a local tuning system can be implemented, which adapts on-line the shunts to control the flexural response produced by a group of flexural modes of the panel resonating in a given frequency band.

An adaptively enriched coarse space for Schwarz preconditioners forP1 discontinuous Galerkin multiscale finite element problems

AbstractIn this paper, we propose a two-level additive Schwarz domain decomposition preconditioner for the symmetric interior penalty Galerkin method for a second-order elliptic boundary value problem with highly heterogeneous coefficients. A specific feature of this preconditioner is that it is based on adaptively enriching its coarse space with functions created by solving generalized eigenvalue problems on thin patches covering the subdomain interfaces. It is shown that the condition number of the underlined preconditioned system is independent of the contrast if an adequate number of functions are used to enrich the coarse space. Numerical results are provided to confirm this claim.

Shear strengthening of reinforced concrete beams with high strength strain-hardening cementitious composites (HS-SHCC)

Strain-hardening cementitious composite (SHCC) was widely recognized as a material that possesses great potential in the repair and strengthening of reinforced concrete (RC) structures. SHCC can usually achieve high ductility with multiple cracking behavior and it also has excellent durability. Moreover, high tensile strength can also be achieved with proper mix design. In this study, conventional RC beams with shear span-to-depth ratio of 1.5:1 and 2.5:1 were cast first, while high-strength SHCC were then cast as thin patches on lateral surfaces of the RC beams to serve as the strengthening layers. The beams were subject to four-point bending test to obtain their ultimate shear capacities. It was observed from the test results that the ultimate shear capacity of strengthened RC beams increases evidently compared to the reference beams. Upon ultimate shear failure, no spalling of surface concrete occurred as it was restrained by the strengthening layers with the formation of stable multiple fine cracks. A finite element model was constructed to simulate the experimental tests. The results of FEM analysis correlated well with experimental results. A numerical parametric study was then carried out to evaluate the influence of the thickness of HS-SHCC layer and the shear span-to-depth ratio. This study concludes the feasibility of the use of high strength SHCC in shear strengthening of RC structures.

Nanoscale Characteristics of Ocular Lipid Thin Films Using Kelvin Probe Force Microscopy.

PurposeTo describe the use of Kelvin probe force microscopy (KPFM) to investigate the electrical surface potential of human meibum and to demonstrate successful use of this instrument on both human meibum and a meibum model system (six-lipid stock [6LS]) to elucidate nanoscale surface chemistry and self-assembly characteristics.Materials and Methods6LS and meibum were analyzed in this study. Mica-supported thin films were created using the Langmuir-Blodgett trough. Topography and electrical surface potential were quantified using simultaneous atomic force microscopy/KPFM imaging.ResultsBoth lipid mixtures formed thin film patches on the surface of the mica substrate, with large aggregates resting atop. The 6LS had aggregate heights ranging from 41 to 153 nm. The range in surface potential was 33.0 to 125.9 mV. The meibum thin films at P = 5 mN/m had aggregates of 170 to 459 nm in height and surface potential ranging from 15.9 to 76.1 mV, while thin films at P = 10 mN/m showed an aggregate size range of 147 to 407 nm and a surface potential range of 11.5 to 255.1 mV.ConclusionsThis study showed imaging of the differences in electrical surface potential of meibum via KPFM and showed similarities in nanoscale topography. 6LS was also successfully analyzed, showing the capabilities of this method for use in both in vitro and ex vivo ocular research.Translational RelevanceThis study describes the use of KPFM for the study of ocular surface lipids for the first time and outlines possibilities for future studies to be carried out using this concept.

First Report of Powdery Mildew Caused by Erysiphe buhrii on Gypsophila capituliflora in China

Gypsophila capituliflora Rupr. (purplehead baby’s breath), a perennial herb, is native to the desert region of northwestern China and Central Asia. It is valuable for ornamental use and preventing land erosion (Mao 1996). In August 2017, during a survey of diseases of desert plants, severe outbreaks of powdery mildew infections with approximately 90% disease incidence on G. capituliflora were observed in the desert region of Alashankoy City, Xinjiang, China. Symptoms first appeared as thin white patches on needle-like leaves, which subsequently turned yellow and necrotic, and resulted in permanent death of plants. Three representative voucher specimens were deposited in the Mycological Herbarium of Tarim University (HMUT6449.1 to 6449.3). Appressoria were well-developed, multilobed or slightly lobed, solitary or opposite in pairs. Conidiophores arose from the top of the mother cell and produced single conidia. Foot cells were cylindrical, straight, or slightly flexuous at the base, 27 to 58 × 5 to 12 μm (n = 30), and were followed by one to three mostly short cells. Conidia were cylindrical to oblong-ellipsoid, 35 to 56 × 12.5 to 18 μm (n = 50), without fibrosin bodies, and showed angular/rectangular wrinkling of outer walls. Germ tubes were produced on the terminal or subterminal position of conidia with lobed appressoria. Chasmothecia were gregarious or scattered, dark brown, and 85 to 195 μm in diameter (n = 30). Appendages were septate, usually irregularly branched, arising from the lower half of the chasmothecia, 35 to 210 μm in length (n = 30). Asci were sessile or short-stalked in shape, 45 to 87 × 23 to 48 μm, and mostly contained two to six colorless ascospores, ellipsoid-ovoid to subglobose, with dimensions of 15 to 30 × 9 to 21 μm (n = 30). The specific measurements and morphological characteristics were consistent with those of Erysiphe buhrii U. Braun (Braun and Cook 2012; Choi et al. 2016). To confirm the identification, the internal transcribed spacer (ITS) and 28S rRNA gene of the three deposited isolates (HMUT6449.1 to 6449.3) were amplified and sequenced following the method of Meeboon and Takamatsu (2015) and deposited in GenBank (accession nos. MH256036 to MH256038). An NCBI-BLAST search indicated that these sequences showed 100% identity of the ITS (559/559 nucleotides) and LSU (805/805 nucleotides) with E. buhrii on G. paniculata (LC009959) and 99.3% identity of the ITS (558/562 nucleotides) with E. buhrii on G. oldhamiana (KU945278). Based on phylogenetic trees generated from maximum likelihood and Bayesian analysis of the combined alignment of ITS and 28S rRNA, the three strains clustered with E. buhrii (MUMH 0787) in an independent clade with 100% bootstrap support value and posterior probability of 1. The pathogenicity test was confirmed by Koch’s postulates. Leaves of six healthy potted plants were gently pressed against diseased leaves for inoculation. Three noninoculated plants served as controls. Each plant was kept in a separate plastic humid chamber in a greenhouse at 25 to 30°C for 7 days. Typical symptoms of powdery mildew, morphologically identical to the original observations on diseased plants, developed on the inoculated plants. No symptoms were observed on the control plants. E. buhrii has been reported on Gypsophila spp. in Hungary, Romania, Ukraine, Turkey, USSR, Argentina, Korea, and Mongolia (Farr and Rossman 2020). To our knowledge, this is the first record of E. buhrii on G. capituliflora. Considering G. capituliflora is one of the major plant species in the local ecosystem, the occurrence of the powdery mildew disease poses a serious threat to the fragile ecological systems of the desert area, and it may continue to accelerate the process of desertification in Xinjiang, China.

Performance Optimization of Polymer Fibre Actuators for Soft Robotics.

Analytical modeling of soft pneumatic actuators constitutes a powerful tool for the systematic design and characterization of these key components of soft robotics. Here, we maximize the quasi-static bending angle of a soft pneumatic actuator by optimizing its cross-section for a fixed positive pressure inside it. We begin by formulating a general theoretical framework for the analytical calculation of the bending angle of pneumatic actuators with arbitrary cross-sections, which is then applied to an actuator made of a circular polymer tube and an asymmetric patch in the shape of a hollow-cylinder sector on its outer surface. It is shown that the maximal bending angle of this actuator can be achieved using a wide range of patches with different optimal dimensions and approximately the same cross-sectional area, which decreases with pressure. We also calculate the optimal dimensions of thin and small patches in thin pneumatic actuators. Our analytical results lead to clear design guidelines, which may prove useful for engineering and optimization of the key components of soft robotics with superior features.

First Report of Powdery Mildew Caused by Leveillula taurica on Capparis spinosa subsp. himalayensis from China

Capparis spinosa subsp. himalayensis (Capparaceae) as a wild plant grows widely in Xinjiang and Tibet of China, as well as northern India and Pakistan (Fici 2015; Zhang and Tucker 2008). Its root, barks, leaves, and fruits are used for the treatment of rheumatism in traditional medicine. Since 2010, C. spinosa subsp. himalayensis has been affected by a powdery mildew with nearly 80% disease incidence in the northwest of Taklimakan desert, Xinjiang, China. Symptoms of powdery mildew first appear as circular to irregular white colonies, which subsequently develop into an abundant growth on the upper and lower surface of the leaves. As the disease progresses, the infection spreads to whole leaves, resulting in leaf death and decreased medicinal value. Two representative specimens were deposited in the Mycological Herbarium of Tarim University (HMUT0911551 and HMUT0911552). Mycelium was abundantly hypophyllous, sometimes amphigenous, forming thin white patches or covering entire leaves. Conidiophores emerged through leaf stomata, singly or branched, and formed dimorphic conidia. Primary conidia were lanceolate with distinct apical points measuring 44 to 63 × 12 to 22 μm. Secondary conidia were ellipsoid to cylindrical measuring 41 to 59 × 12 to 20 μm. Both conidia were hyaline with angular/rectangular wrinkling of the outer walls. The chasmothecia were nearly gregarious and globe-shaped, 98 to 249 μm in diameter, often immersed in dense mycelial tomentum with numerous asci. Numerous and well-developed appendages on the lower half of the chasmothecia were irregularly branched. Asci were stalked, long or wide ellipsoidal in shape, and 84 to 136 × 25.4 to 56.8 μm. The asci usually contained two ellipsoidal, colorless ascospores measuring 22.8 to 46.7 × 15.4 to 28.7 μm. The specific measurements and morphological features were consistent with those of Leveillula taurica (Lev.) Arnaud (Braun and Cook 2012). To confirm the identification, the internal transcribed spacer (ITS) and 28S rDNA of isolates HMUT0911551 and HMUT0911552 were amplified and sequenced as described by Song et al. (2016). NCBI BLAST search indicated that the ITS sequences (GenBank accession nos. MG600237 and MG600238) were 99.8% (identity: 610/611) similar to L. taurica on C. spinosa and Rosa sp. from Iran (accession nos. AB045002 and AB667881) (Khodaparast et al. 2001). It also indicated that the 28S sequences (GenBank accession nos. MG600239 and MG600240) were 100% similar to L. taurica on Glancium oxylobum and Alcea sp. from Iran (accession nos. AB080474 and AB080467) (Takamatsu et al. 2008). Pathogenicity was confirmed through inoculation by gently pressing diseased leaves onto leaves of healthy potted plants. Six inoculated plants were kept under a plastic humid chamber, and three noninoculated plants served as the control. The plants were placed under greenhouse conditions at 25 to 30°C for 7 days. Typical symptoms of powdery mildew developed on the inoculated plants, with identical morphology to the original observation on diseased leaves. No symptoms were seen on the control plants. To our knowledge, this is the first report of powdery mildew caused by L. taurica on C. spinosa subsp. himalayensis. This study extends the host range of L. taurica.

Boston Ivy Disk-Inspired Pressure-Mediated Adhesive Film Patches.

Boston ivy (Parthenocissus tricuspidata) climbs brick walls using its tendril disks, which excrete a sticky substance to perform binding and attachment. While the cellular structures and adhesive substances involved have been identified for decades, their practical applicability as an adhesive has not yet been demonstrated. A Boston ivy disk-inspired adhesive film patch system is reported in which structural and compositional features of the Boston ivy disk are mimicked with a form of thin adhesive film patches. In analogy to the sticky disk of a mature ivy in which porous microchannels are occupied by catechol-containing microgranules on the bound site, 3,4-dihydroxylphenylalanine bolaamphiphile nanoparticle (DOPA-C7 NP)-coated alginate microgels are two-dimensionally positioned into the cylindrical holes that are periodically micropatterned on the flexible stencil film. Finally, it is demonstrated that the pressurization of the patch breaks the microgels filled in the holes, releasing the polysaccharides and leading to crosslinking with DOPA-C7 NPs via ligandation with combined Ca2+ and Fe3+ ions, thus enabling development of a pressure-mediated adhesion technology.

Recent evolution of Marmolada glacier (Dolomites, Italy) by means of ground and airborne GPR surveys

A 10-year-long evolution of ice thickness and volume of the Marmolada glacier is presented. Quantitative measurements have been performed by using two different Ground Penetrating Radar (GPR) datasets. A ground-based survey using two different ground-coupled systems equipped with 100 MHz and 35 MHz antennas was performed in 2004. In 2015 the dataset was collected by using a helicopter-borne step frequency GPR equipped with a 100 MHz antenna. Through a critical discussion of the two different methodologies, we show how both approaches are useful to estimate the ice volume within a glacier, as well as its morphological characteristics and changes with time, even if datasets are acquired in different periods of the year.The observed 2004–2014 ice volume reduction of the Marmolada glacier is equal to about 30%, while the area covered by ice decreased by about 22%. The glacier is now splitted in several separated units. It is very likely that the fragmentation of the Marmolada glacier observed in the period 2004–2014 was accelerated due to irregular karst topography. By applying the observed 2004–2014 ice-melting trend for the future although the Marmolada glacier might behave slightly differently compared to glaciers on non-karstic terrains owing to dominant vertical subglacial drainage, it will likely disappear by the year 2050. Only few isolated very small and thin ice patches will eventually survive due to avalanche feeding and shading at the foot of the north-facing cliffs.

Fatal Peritoneal Migration of Strongylus edentatus in a Foal

A 7-month-old female mixed breed foal with a 2-day history of recumbency and inability to open its mouth convulsed acutely and died and was submitted for necropsy examination. The foal was thin and large patches of haemorrhage were present throughout the peritoneal wall, the diaphragmatic surfaces and the retroperitoneum. Numerous nematode larvae were visible on the serosal surfaces and penetrated and embedded into the subserosa associated with the haemorrhages. The dorsal portion of the abdominal diaphragm had a partial tear and large numbers of nematodes were within the muscle fibres. Histologically, the larvae had a smooth cuticle, polymyarian/coelomyarian musculature and multinucleated intestinal cells, and were typically surrounded by haemorrhage, neutrophils, dense fibrovascular connective tissue and rare multinucleated giant cells. Parasitological examination identified the larvae as Strongylus edentatus based on the morphology of the buccal capsule. Additionally, there was severe muscle necrosis of the tongue and liver tissue analysis detected selenium deficiency. S. edentatus infections are uncommon in California, USA, and are typically non-lethal. In this case, the selenium deficiency may have led to immunosuppression, resulting in the hyperinfection with S. edentatus, and to the muscle damage and tear of the diaphragm. Although ivermectin treatment was indicated in the history, inadequate deworming or anthelmintic resistance may have played a role in the severity of infection.

Health monitoring of reinforced concrete structures under impact using multiple piezo-based configurations

With new advancements in construction technologies, the researchers and engineers have started taking a greater interest in structural health monitoring (SHM). Some of these techniques involve monitoring of structures using piezo sensors, made of smart materials such as Lead Zirconate Titanate (PZT) in form of thin patches. One of such techniques which has shown promising results in detecting damage at incipient stages is the electro-mechanical impedance (EMI) technique. In this study, damages incurred due to impact loading on reinforced concrete (RC) slabs were studied using four types of piezo-based configurations, namely concrete vibration sensor (CVS) with circular PZT patch (CVS-C), CVS with square PZT patch (CVS-S), resin jacketed piezo (RJP) sensor with a single layer of epoxy (RJP-I) and RJP with double layer of epoxy (RJP-II). The tests showed a successful detection of damage due to impacts by all the four types of piezo-based configurations. The CVS-C and RJP-I proved to be more sensitive in quantifying damage via root mean square deviation (RMSD) variation, i.e. increasing RMSD values with an increase in the number of impacts. In addition, CVS-C, CVS-S, and RJP-II, specifically detected an imminent failure in one of the RC slabs. The equivalent structural parameters computed from the admittance signatures showed a reduction in the equivalent stiffness with the incremental damage. An empirical model was successfully developed for each of the sensors to determine the remaining life of the structure based on a non-dimensional stiffness loss factor. The equivalent stiffness-based model was found to be an improvement over the previous damping-based models which can be reliably used in the field.

Delineating sources of groundwater recharge and carbon in Holocene aquifers of the central Gangetic basin using stable isotopic signatures

ABSTRACTStable isotopes of water (δ2H, δ18O) and δ13CTIC were used as a tool to trace the recharge processes, natural carbon (organic and inorganic) source and dynamics in the aquifers of the central Gangetic basin, India. Stable isotope (δ2H, δ18O) record of groundwater (n = 105) revealed that the groundwater of Piedmont was recharged by meteoric origin before evaporation, while aquifers of the older and younger alluvium were recharged by water that had undergone evaporation loss. River Ganges and its tributaries passing through this area have very little contribution in recharging while ponds play no role in the recharging of adjacent aquifers. The connectivity of shallow aquifers of aquitard formation (comprised of clay/sandy clay with thin patches of fine grey sand), i.e. 25–60 m below ground level (bgl) with the main upper aquifer (at a depth of >120 m bgl) was found to be higher in older and younger alluvium. Negative values of δ13CTIC (median −9.6 ‰; range −13.2 to −5.4 ‰) and high TIC (median 35 mM; range 31–46 mM) coupled with low TOC (median 1.35 mg/L; range 0.99–1.77 mg/L) indicated acceleration in microbial activity in the younger alluvium, especially in the active floodplain of river Ganges and its proximity.

Thickness-Encoded Micropatterns in One-Component Thermoresponsive Polymer Brushes for Culture and Triggered Release of Pancreatic Tumor Cell Monolayers and Spheroids

Fabrication, characterization, and application of micropatterned one-component poly(di(ethylene glycol)methyl ether methacrylate) (PDEGMA) brushes for monolayer cell and spheroid culture and temperature-triggered release are reported. Micropatterns of various shapes and sizes were designed to possess a unique functionality imparted by thermoresponsive thin PDEGMA patches, which are cell adhesive at 37 °C, embedded in a much thicker cell-resistant PDEGMA matrix that does not exhibit measurable thermoresponsive properties. Depending on the cell seeding density, PaTu 8988t human pancreatic tumor cells or spheroids were cultured area-selectively, confined by the 40 ± 4 nm thick passivating PDEGMA matrix, and could be released on demand by a mild thermally triggered brush swelling in the 5 ± 1 nm thin regions. As shown by surface plasmon resonance (SPR) measurements, in contrast to the thinner brushes, the thicker brushes exhibited virtually no fibronectin adhesive properties at 37 °C, whereas at 25 °C, both areas showed similar protein resistant behavior. The quasi-2D thickness-encoded micropatterns were shown to be useful templates for the growth of 3D multicellular aggregates. Thermally induced release after 5 days of incubation afforded 3D cell spheroids comprising up to 99% viable cells demonstrating that the system can be used as a 3D spheroid in vitro model for basic tumor research and anticancer drug screenings.

Fabrication and Photoelectrical Properties of Thin Film g-C3N4 Modified TiO2 Nanotube Photoelectrode

Graphitic carbon nitride (g-C3N4) is an interesting conjugated polymer, being metal-free, stable and active in the lower ranges of visible light with a bandgap of 2.7eV [1]. Titanium dioxide (TiO2) has been researched for photoelectrolysis of water since the late 1960. It is one of the most researched wide-band gap semiconductors, which is only active in ultra-violet-light range [2]. In this work, we report the fabrication and photoelectrical properties of thin film g-C3N4 modified TiO2 nanotube photoelectrodes. Graphitic carbon nitride (g-C3N4) was produced with a thermal polycondensation of urea in nitrogen atmosphere for 2 hours at 550oC, 575oC and 600oC in two different ovens. The samples were designated F550, F575 and F600 for the samples made in the MTI Corporation GSL-1100X Tube Furnace, and TC at the start for the Lenton WHT6/30 Thermal Chamber. To achieve an even film on the substrate, urea was placed in a quartz crucible for the tube furnace and covered with aluminium foil. Holes were cut in the foil and the substrate was placed on top, not covering the holes. More aluminium foil was used to seal the crucible. The substrate was TiO2 nanotubes produced by anodization in ethylene glycol at 60V for 3 hours. Preliminary experiments have been carried out and shown enhancement of photocurrent response. The samples were characterized with UV-vis spectroscopy, Scanning Electron Microscopy (SEM) imaging, Energy Dispersive X-Ray (EDX) and X-ray Diffraction (XRD). For the UV-vis reflectance spectroscopy, the tube furnace results are shown in fig. 1, where F550, F575 and F600 shows significantly increased absorption for wavelengths over 500nm. For F575, the pure TiO2 and all the samples made in the thermal chamber, a clear absorption edge was present around 400nm, corresponding to the TiO2 bandgap. F550 and F600 do not show the absorption edge, as they show an increased absorption all the way down to 350nm. It is also clear that the surface has been modified by looking at the samples, especially F600 which has gotten a very dark, almost black, colour, as shown in fig. 2. The SEM image, fig. 3, shows the TiO2 nanotubes with thin patches of g-C3N4 spread intermittently on top, and the EDX measurements give the variation in g-C3N4 density from sample to sample. F550 and F600 show an increased g-C3N4 (12-17% of C and N) content compared to all the other samples (around 1% C and none detected of N). XRD was done on the powders to verify that the substance was indeed g-C3N4. In summary, depositing g-C3N4 on top of TiO2 nanotubes can give a significant increase in absorption across the whole visible spectrum, and this probably comes from the increased g-C3N4 content seen in F550 and F600. Though even a small amount of g-C3N4 will increase the absorption in the 500-800nm range. [1] W.-J. Ong, L.-L. Tan, Y. H. Ng, S.-T. Yong, and S.-P. Chai, “Graphitic Carbon Nitride (g-C3N4)-Based Photocatalysts for Artificial Photosynthesis and Environmental Remediation: Are We a Step Closer To Achieving Sustainability?,” Chem. Rev., vol. 116, no. 12, pp. 7159–7329, Jun. 2016. [2] K. Hashimoto, H. Irie, and A. Fujishima, “TiO 2 Photocatalysis: A Historical Overview and Future Prospects,” Jpn. J. Appl. Phys., vol. 44, no. 12, pp. 8269–8285, Dec. 2005. Figure 1

Correlation of Reflectance Confocal Microscopy and Dermatopathology Findings in a Case of Acrodermatitis Chronica Atrophicans

Acrodermatitis chronica atrophicans (ACA) that is characterized by thin, papery dry, translucent, and alopecic patches with visible superficial veins is a late cutaneous manifestation of Lyme borreliosis. Clinical findings, a history of exposure to tick bite, and serology are helpful for the diagnosis of ACA and sometimes a biopsy is performed to rule out other infectious or inflammatory processes. In this study, we report reflectance confocal microscopy (RCM) findings in a case of ACA. RCM examination revealed a flattened surface with broadened skin folds, a flattened dermoepidermal junction with few papillae and less bright basal cells and multiple small bright reflecting spots in the dermis. To the best of our knowledge, this is the first description of the RCM findings in this disorder.

Atlas for the properties of elemental two-dimensional metals

Common two-dimensional (2D) materials have a layered 3D structure with covalently bonded, atomically thin layers held together by weak van der Waals forces. However, in a recent transmission electron microscopy experiment, atomically thin 2D patches of iron were discovered inside a graphene nanopore. Motivated by this discovery, we perform a systematic density-functional study on atomically thin elemental 2D metal films, using 45 metals in three lattice structures. Cohesive energies, equilibrium distances, and bulk moduli in 2D are found to be linearly correlated to the corresponding 3D bulk properties, enabling the quick estimation of these values for a given 2D metal and lattice structure. In-plane elastic constants show that most 2D metals are stable in hexagonal and honeycomb, but unstable in square 2D structures. Many 2D metals are surprisingly stable against bending.