A Novel Gelatin-Based Sustained-Release Molluscicide for Control of the Invasive Agricultural Pest and Disease Vector Pomacea canaliculata

Pomacea canaliculata, one of the 100 most destructive invasive species in the world, and it is an important intermediate host of Angiostrongylus cantonensis. The molluscicides in current use are an effective method for controlling snails. However, most molluscicides have no slow-release effect and are toxic to nontarget organisms. Thus, these molluscicides cannot be used on a large scale to effectively act on snails. In this study, gelatin, a safe and nontoxic substance, was combined with sustained-release molluscicide and was found to reduce the toxicity of niclosamide to nontarget organisms. We assessed the effects of gelatin and molluscicide in controlling P. canaliculata snails and eggs. The results demonstrated that the niclosamide retention time with 1.0% and 1.5% gelatin sustained-release agents reached 20 days. Additionally, the mortality rate of P. canaliculata and their eggs increased as the concentration of the niclosamide sustained-release agents increased. The adult mortality rate of P. canaliculata reached 50% after the snails were exposed to gelatin with 0.1 mg/L niclosamide for 48 h. The hatching rate of P. canaliculata was only 28.5% of the normal group after the treatment was applied. The sustained-release molluscicide at this concentration was less toxic to zebrafish, which means that this molluscicide can increase the safety of niclosamide to control P. canaliculata in aquatic environments. In this study, we explored the safety of using niclosamide sustained-release agents with gelatin against P. canaliculata. The results suggest that gelatin is an ideal sustained-release agent that can provide a foundation for subsequent improvements in control of P. canaliculata.     

‘One‐Touch’ Voltammetry of Microparticles for the Identification of Corrosion Products in Archaeological Lead

Voltammetry of microparticles is applied to the identification of lead corrosion products by means of an essentially non‐invasive ‘one‐touch’ technique based on the use of graphite pencil. This methodology permits the mechanical attachment of few nanograms of sample from the surface of lead archaeological artefacts to a paraffin‐impregnated graphite electrode, which, upon immersion in aqueous electrolytes, provides distinctive voltammetric responses for litharge and cotunnite‐ anglesite‐, cerusite‐based corrosion products. The reported method is applied to the identification of corrosion products in archaeological lead pieces from different Iberian sites in Valencia (Spain).     

Transoral Robotic Surgery (TORS): Glottic Microsurgery in a Canine Model

OBJECTIVES/HYPOTHESIS: We hypothesize that bimanual, three-dimensional robotic surgery will prove valuable for glottic microsurgical procedures. STUDY DESIGN: To test this hypothesis, we developed and optimized a canine model for glottic microsurgery using a commercially available surgical robot. Methods Using a da Vinci Surgical Robot (Intuitive Surgical, Inc., Sunnyvale, CA), glottic microsurgery was performed with a hydrodissection technique in a canine model. The experiments were performed on two orotracheal intubated mongrel dogs under general anesthesia in the supine position on a standard operating room table. A videoscope and two, 360-degree rotating, 5- and 8-mm, wrested-end effector instruments were introduced transorally with three robotic arms. The surgeon performed the actual procedures while positioned at a robotic system console that was located across the operating room suite. The procedure was performed in duplicate and was documented with still and video photography. RESULTS: Glottic microsurgery was successfully performed using the da Vinci Surgical Robot, with both 5- and 8-mm instrumentation. The smaller, 5-mm instruments afforded greater visualization of the operative site and increased maneuverability, which resulted in reduced operative time. The robotic system provided excellent visualization as well as controlled and delicate microdissection at the vocal cord level. CONCLUSIONS: Robotic laryngeal microsurgery is technically feasible in the canine model and warrants consideration for evaluation in controlled human trials.     

Image-based hysteresis reduction for the control of flexible endoscopic instruments

The limited dexterity of conventional flexible endoscopic instruments restricts the clinical procedures that can be performed by flexible endoscopy. Advanced instruments with a higher degree of dexterity are being developed, but are difficult to control manually. Adding actuators to these instruments may make them easier to control. However, the intrinsic hysteresis that is present between the actuators and the tip of the instrument needs to be reduced in order to allow accurate control. We present an estimation algorithm that determines the hysteresis between the actuators and the instrument tip in all three degrees of freedom of the instrument: insertion, rotation, and bending. The estimation is performed on-line. The endoscopic images are used as the only feedback, and no additional sensors are placed on the instrument, which is beneficial for application in clinical practice. The estimated parameters are used to reduce the hysteresis that is present. Experimental validation showed a hysteresis reduction of 75%, 78%, and 73% for the insertion, rotation, and bending degrees of freedom, respectively.     

Micro‐Raman spectroscopy identification of urinary stone composition from ureteroscopic lithotripsy urine powder

Urolithiasis is a prevalent, disturbing, and highly recurrent disease. Knowing the composition of a urinary stone is important for prevention purposes. Traditional urinary stone analysis methods need large stone fragments for analysis. However, the advancement of ureteroscopic lithotripsy (URSL) has resulted in micro‐stone fragments and unapparently expelled urinary stone powder. In this study, we developed a micro‐Raman spectroscopy (MRS) based diagnosis method for detecting micro‐stones or stone powders in urine after URSL. In our experiment, urine samples of 10 ml each were collected from 12 patients over the fragmented stone site in the ureter after the URSL procedure. The post‐URSL urine sediments extracted from urine were analyzed by MRS. The small urinary stones caught by grasping forceps were analyzed by both MRS and Fourier‐transform infrared (FTIR) spectroscopy. We have identified common urinary stone compositions: calcium oxalate monohydrate (COM), calcium oxalate dihydrate (COD), dicalcium phosphate dihydrate (DCPD), calcium phosphate hydroxide (hydroxyl apatite or HAP), and uric acid, by using a 632.8 nm He‐Ne laser for excitation, a 100× microscope objective lens for irradiation and collection, and a short photobleaching time for fluorescent background reduction. Thus, we developed an MRS‐based method for analyzing the composition of urinary stone powders directly from the urine samples after the URSL procedure. This approach provides a quick and convenient method for urinary stone analysis. Copyright © 2009 John Wiley & Sons, Ltd.     

Tight bounds for the vertices of degree k in minimally k‐connected graphs

For minimally k‐connected graphs on n vertices, Mader proved a tight lower bound for the number of vertices of degree k in dependence on n and k. Oxley observed 1981 that in many cases a considerably better bound can be given if is used as additional parameter, i.e. in dependence on m, n, and k. It was left open to determine whether Oxley's more general bound is best possible. We show that this is not the case, but give a closely related bound that deviates from a variant of Oxley's long‐standing one only for small values of m. We prove that this new bound is best possible. The bound contains Mader's bound as special case.     

Wearable and Miniaturized Sensor Technologies for Personalized and Preventive Medicine

The unprecedented medical achievements of the last century have dramatically improved our quality of life. Today, the high cost of many healthcare approaches challenges their long‐term financial sustainability and translation to a global scale. The convergence of wearable electronics, miniaturized sensor technologies, and big data analysis provides novel opportunities to improve the quality of healthcare while decreasing costs by the very early stage detection and prevention of fatal and chronic diseases. Here, some exciting achievements, emerging technologies, and standing challenges for the development of non‐invasive personalized and preventive medicine devices are discussed. The engineering of wire‐ and power‐less ultra‐thin sensors on wearable biocompatible materials that can be placed on the skin, pupil, and teeth is reviewed, focusing on common solutions and current limitations. The integration and development of sophisticated sensing nanomaterials are presented with respect to their performance, showing exemplary implementations for the detection of ultra‐low concentrations of biomarkers in complex mixtures such as the human sweat and breath. This review is concluded by summarizing achievements and standing challenges with the aim to provide directions for future research in miniaturized medical sensor technologies.     

A High-Precision,Low-Voltage Pulsed Field Ablation Device with Capability of Minimally Invasive Surgery

Pulsed field ablation is a novel approach to treating 33.5 million patients with atrial fibrillation and offers a tissue-specific advantage over conventional radiofrequency ablation and cryoablation. However, for complex structural targets in the heart, current electrodes often damage non-target areas due to inaccurate ablation and have to employ electrical pulses with amplitudes of several kilovolts. Herein, materials and designs of a catheter-integrated microelectrode and sensors that can be used for high-precision and low-voltage pulsed field ablation through minimally invasive operation on a large animal model, is reported. The device with a new electrode configuration supports point-by-point ablation with a width of 3.8 mm (≈1/10 that of a typical ablation electrode) for individual lesions at the voltage of 300 V (an order of magnitude reduction compared to the current state-of-the-art). More impressively, the integrated catheter allows for pulsed field ablation on the large animal heart through minimally invasive surgery and blocks the electrical conduction pathway on the heart, which is the key to treating atrial fibrillation. This catheter-integrated device will enhance the efficiency and safety of pulsed field ablation, especially for complex cardiac structures, thus facilitating its move to the clinic.     

The packing property

A clutter (V, E) packs if the smallest number of vertices needed to intersect all the edges (i.e. a minimum transversal) is equal to the maximum number of pairwise disjoint edges (i.e. a maximum matching). This terminology is due to Seymour 1977. A clutter is minimally nonpacking if it does not pack but all its minors pack. An m×n 0,1 matrix is minimally nonpacking if it is the edge-vertex incidence matrix of a minimally nonpacking clutter. Minimally nonpacking matrices can be viewed as the counterpart for the set covering problem of minimally imperfect matrices for the set packing problem. This paper proves several properties of minimally nonpacking clutters and matrices. Received: December 1, 1997 / Accepted: April 6, 1999?Published online October 18, 2000     

The putative use of alpha-1-acid glycoprotein as a non-invasive marker of fibrosis

The acute phase response to injury or infection results in alterations in the expression of the plasma proteins produced by the liver. Many of these biomolecules are glycosylated with oligosaccharide chains covalently attached to the polypeptide backbone and the extent and composition of this glycosylation can be altered in a disease-dependent manner. Of particular interest is the observation that the acute phase glycoprotein, alpha-1-acid glycoprotein (AGP) has altered glycosylation in several physiological and pathological conditions. It is posited that changes induced in liver diseases may reflect disease severity and may therefore act as a non-invasive marker of fibrosis. This study has investigated the glycosylation of AGP in the plasma of people with varying degrees of cirrhosis and fibrosis. Hyperfucosylation was observed in all disease samples in comparison to normal plasma and was significantly increased in cirrhosis. Both sialic acid and N-acetylgalactosamine (GalNAc) were negatively associated with fibrosis. Two samples were found to express GalNAc, which as a constituent of the glycosylation of serum proteins is rare. In conclusion, fucose, sialic acid and other aspects of the glycosylation of AGP are influenced by the degree of fibrosis and as such may prove a valuable prognostic indicator of the development of cirrhosis.