Esthetic and endosurgical management of Turner's hypoplasia; a sequlae of trauma to developing tooth germ.

Turner's hypoplasia usually manifests as a portion of missing or diminished enamel, generally affecting one or more permanent teeth in the oral cavity. A case report of 8 year old girl who met with trauma at 2 years of age leading to primary incisors being knocked out, reported after 6 years with complaint of pain and discharge in her anterior malformed teeth is discussed in this article. The permanent incisors erupted with dilacerated crown, root malformations and missing enamel.

Surgical repositioning of intruded immature permanent incisor: an updated treatment concept.

Intrusion of immature permanent anterior teeth presents a great dilemma due to variety of treatment options. The ideal treatment option is the one with least probability of developing complications like external root resorption, obliteration of pulp canal, marginal bone loss etc. This paper presents a case report with treatment strategy of repositioning, splinting, successfully attempted apexification and obturation of a completely intruded immature permanent central incisor.

Lotus-like biomimetic hierarchical structures developed by the self-assembly of tubular plant waxes.

Hierarchical roughness is beneficial for superhydrophobic and self-cleaning surfaces. Biomimetic hierarchical surfaces were fabricated by replication of a micropatterned master surface and self-assembly of two kinds of tubular wax crystals, which naturally occur on the superhydrophobic leaves of Tropaeolum majus (L.) and Leymus arenarius (L.

TNF-alpha gene polymorphism and TNF-alpha levels in obese Asian Indians with obstructive sleep apnea.

Background: Obstructive sleep apnea (OSA) is emerging as a significant disorder in India. Tumor necrosis factor-alpha (TNFalpha) is an important marker of inflammation. Recent data indicate that inflammation may be an important correlate of OSA.

Separation and identification of enzymatically prepared dephosphorylated products of myo-inositolhexakisphosphate using LC-MS.

LC-MS technique described here is a new way for the separation and direct determination of UV-Vis insensitive inositol phosphates (InsP(2)-InsP(6)). This circumvents the need of radioisotopic labeling and post-column derivatization techniques. The method involves separation of various enzymatically dephosphorylated derivatives of InsP(6) on C(18)-column using MeOH/H(2)O (30:70 v/v) and their identification using electron spray ionization MS in positive ion mode (+pESI-MS).

Nanoscale adhesion, friction and wear studies of biomolecules on silane polymer-coated silica and alumina-based surfaces.

Proteins on biomicroelectromechanical systems (BioMEMS) confer specific molecular functionalities. In planar FET sensors (field-effect transistors, a class of devices whose protein-sensing capabilities we demonstrated in physiological buffers), interfacial proteins are analyte receptors, determining sensor molecular recognition specificity. Receptors are bound to the FET through a polymeric interface, and gross disruption of interfaces that removes a large percentage of receptors or inactivates large fractions of them diminishes sensor sensitivity.

Manipulating microobject by using liquid droplet as a transporting vehicle.

Liquid droplets are proposed as transport vehicles for manipulating microobjects. An atomic force microscope (AFM) cantilever is used as a gripper to pick-up a droplet and then a particle from a hydrophobic substrate. The droplet and the particle are then released to a hydrophilic substrate from the cantilever.

Slip-length measurement of confined air flow using dynamic atomic force microscopy.

We present an experimental measurement of the slip length of air flow close to solid surfaces using an atomic force microscope (AFM) in dynamic mode. The air was confined between a glass surface and a spherical glass particle glued to an AFM cantilever. The Knudsen number was varied continuously over three decades by varying the distance between the two surfaces.

Obstructive sleep apnoea correlates with C-reactive protein in obese Asian Indians.

Background: C-reactive protein (CRP), a marker of systemic inflammation, is an important predictor of future cardiovascular events. Whether the relationship of obstructive sleep apnoea (OSA) and CRP is independent of adiposity, needs to be investigated.

Objective: To investigate the association of CRP levels with OSA in the obese and their comparison with lean subjects without OSA in Asian Indians residing in India.

A nanoscale friction investigation during the manipulation of nanoparticles in controlled environments.

Future micro/nanodevices will contain very small features such that liquid lubrication is not practical and inherent lubricity is needed. In this study, a nanoscale friction investigation was carried out during the manipulation of Au and SiO(2) nanoparticles on silicon using atomic force microscopy (AFM). Nanoparticle sliding was characterized by quantifying the lateral force associated with the AFM tip twisting as it hits the particle edge.

Studies on the dephosphorylation of phytic acid in livestock feed using phytase from Aspergillus niger van Teighem.

Phytase from Aspergillus niger van Teighem efficiently hydrolyses phytate phosphorus present in various commercial live stock feeds and was not inactivated by various formulations and antibiotics present. The enzyme retained 90-95% phytase activity at 55 degrees C, pH 2.5 after 72 h of incubation with all the commercial feeds tested, thus indicating its suitability in feed application.

Effect of rubbing load on nanoscale charging characteristics of human hair characterized by AFM based Kelvin probe.

The manageability and feel of human hair is significantly affected by its surface charge. Understanding and developing ways to control charge build up is hence highly beneficial. Previous studies have looked at static charging characteristics of hair on a macroscale.

Handedness, Hinduism and sculpture: searching for evidence of lateralisation.

The majority of people throughout the world show extreme preference for the right hand. We studied lateral bias depicted in ancient Indian sculptures dating between the 7th and 9th centuries ad. A total of 288 sculptures were selected from various excavation sites/museums and the frequencies were computed on 13 different criteria in order to see the preferential bias for hand depicted in sculptures of male and female figures.

Capillary effects and instabilities in nanocontacts.

Several examples of instabilities related to the capillary effects during nanocontacts are studied. For the single-asperity contact, there is a significant negative Laplace pressure inside water capillary bridges and the bridge may become unstable with respect to the phase transition, leading to an unstable capillary force. For the contact of two rough solid surfaces, the capillary force is also unstable with respect to small variations of roughness.

Dynamic effects of bouncing water droplets on superhydrophobic surfaces.

Superhydrophobic surfaces have considerable technological potential for various applications due to their extreme water repellent properties. Superhydrophobic surfaces may be generated by the use of hydrophobic coating, roughness, and air pockets between solid and liquid. Dynamic effects, such as the bouncing of a droplet, can destroy the composite solid-air-liquid interface.

Phase behavior of capillary bridges: towards nanoscale water phase diagram.

Water capillary bridges often condense at contact spots between small particles or asperities. The capillary adhesion force caused by these bridges is a major component of the attractive adhesion force, and thus it significantly affects the nanotribological performance of contacting surfaces. Recent atomic force microscope (AFM) measurements indicate that phase behavior of water in these tiny bridges may be different from macroscale water behavior.

Adhesion, friction and wear on the nanoscale of MWNT tips and SWNT and MWNT arrays.

The nanotribological characterization of carbon nanotubes is fundamental for the exploration of new sliding applications. In this study, a comprehensive investigation of adhesion, friction and wear of a multiwalled nanotube (MWNT) tip, and SWNT (single-walled nanotube) and MWNT arrays has been carried out. A nonlinear response of the MWNT tip is observed when the tip is brought into and out of contact with various surfaces.

Nanomechanical and nanotribological characterization of noble metal-coated AFM tips for probe-based ferroelectric data recording.

Probe-based data recording is being developed as an alternative technology for ultrahigh areal density. In ferroelectric data storage, a conductive atomic force microscope (AFM) probe with a noble metal coating is placed in contact on lead zirconate titanate (PZT) film, which serves as the ferroelectric material. A crucial mechanical reliability concern is tip wear during contact of the ferroelectric material with the probe.

Meniscus and viscous forces during separation of hydrophilic and hydrophobic smooth/rough surfaces with symmetric and asymmetric contact angles.

Adhesive or repulsive forces contributed by both meniscus and viscous forces can be significant and become one of the main reliability issues when the contacting surfaces are ultra smooth, and the normal load is small, as is common for micro/nano devices. In this study, both meniscus and viscous forces during separation for smooth and rough hydrophilic and hydrophobic surfaces are studied. The effects of separation distance, initial meniscus height, separation time, contact angle and roughness are presented.

Nanotribology and nanomechanics in nano/biotechnology.

Owing to larger surface area in micro/nanoelectromechanical systems (MEMS/NEMS), surface forces such as adhesion, friction, and meniscus and viscous drag forces become large when compared with inertial and electromagnetic forces. There is a need to develop lubricants and identify lubrication methods that are suitable for MEMS/NEMS. For BioMEMS/BioNEMS, adhesion between biological molecular layers and the substrate, and friction and wear of biological layers may be important, and methods to enhance adhesion between biomolecules and the device surface need to be developed.

Wetting behaviour during evaporation and condensation of water microdroplets on superhydrophobic patterned surfaces.

Superhydrophobic surfaces have considerable technological potential for various applications due to their extreme water repellent properties. The superhydrophobic surfaces may be generated by the use of hydrophobic coating, roughness and air pockets between solid and liquid. The geometric effects and dynamic effects, such as surface waves, can destroy the composite solid-air-liquid interface.

Nanoscale friction and wear maps.

Friction and wear are part and parcel of all walks of life, and for interfaces that are in close or near contact, tribology and mechanics are supremely important. They can critically influence the efficient functioning of devices and components. Nanoscale friction force follows a complex nonlinear dependence on multiple, often interdependent, interfacial and material properties.

Nanotribology, nanomechanics and nanomaterials characterization.

Nanotribology and nanomechanics studies are needed to develop fundamental understanding of interfacial phenomena on a small scale and to study interfacial phenomena in magnetic storage devices, nanotechnology and other applications. Friction and wear of lightly loaded micro/nanocomponents are highly dependent on the surface interactions (a few atomic layers). These structures are generally coated with molecularly thin films.

Patterned nonadhesive surfaces: superhydrophobicity and wetting regime transitions.

Nonadhesive and water-repellent surfaces are required for many tribological applications. We study mechanisms of wetting of patterned superhydrophobic Si surfaces, including the transition between various wetting regimes during microdroplet evaporation in environmental scanning electron microscopy (ESEM) and for contact angle and contact angle hysteresis measurements. Wetting involves interactions at different scale levels: macroscale (water droplet size), microscale (surface texture size), and nanoscale (molecular size).