A Transient Printed Soil Decomposition Sensor Based on a Biopolymer Composite Conductor.

Soil health is one of the key factors in determining the sustainability of global agricultural systems and the stability of natural ecosystems. Microbial decomposition activity plays an important role in soil health; and gaining spatiotemporal insights into this attribute is critical for understanding soil function as well as for managing soils to ensure agricultural supply, stem biodiversity loss, and mitigate climate change. Here, a novel in situ electronic soil decomposition sensor that relies on the degradation of a printed conductive composite trace utilizing the biopolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) as a binder is presented.

Rapid Fabrication of Low-Cost Thermal Bubble-Driven Micro-Pumps.

Thermal bubble-driven micro-pumps are an upcoming actuation technology that can be directly integrated into micro/mesofluidic channels to displace fluid without any moving parts. These pumps consist of high power micro-resistors, which we term thermal micro-pump (TMP) resistors, that locally boil fluid at the resistor surface in microseconds creating a vapor bubble to perform mechanical work. Conventional fabrication approaches of thermal bubble-driven micro-pumps and associated microfluidics have utilized semiconductor micro-fabrication techniques requiring expensive tooling with long turn around times on the order of weeks to months.

Two versus 3 lag screws for fixation of long oblique proximal phalanx fractures of the fingers: a cadaver study.

Purpose: To compare 2- versus 3-screw fixation for oblique fractures of the proximal phalanx in a cadaver model that simulates active finger motion.

Methods: We experimentally cut the proximal phalanges of the index, middle, and ring fingers of 9 cadaveric hands. Five fingers were assigned to a control group with no fixation, and 22 were fixed with either 2 or 3 lag screws.

Zygomaticomaxillary complex fractures and their association with naso-orbito-ethmoid fractures: a 5-year review.

Background: Zygomaticomaxillary complex fractures associated with ipsilateral naso-orbito-ethmoidal fractures are more complex injuries than isolated zygomaticomaxillary complex fractures. This injury pattern can have significant long-term morbidity if not recognized and treated appropriately during the initial operation. The purpose of this study is to compare mechanisms of injury, treatment, and outcome between patients with zygomaticomaxillary complex fractures and those with zygomaticomaxillary complex and ipsilateral naso-orbito-ethmoidal fractures.

Collagen nerve protector in rat sciatic nerve repair: A morphometric and histological analysis.

Peripheral nerve repair is often complicated by fibroblastic scar formation, nerve dysfunction, and traumatic neuroma formation. Use of bio-absorbable protective wraps may improve outcomes of these repairs. This study histologically compared the incidence of neuroma formation, connective tissue proliferation, and axonal regrowth in transected rat sciatic nerves repaired with and without tubular collagen nerve sleeves.

Biomechanics and histology of intact and repaired digital nerves: an in vitro study.

Purpose: To investigate the biomechanical properties of intact and repaired cadaver digital nerves.

Methods: Ultimate tensile failure strength and stiffness were determined in 67 human cadaver digital nerves. Total nerve area, fascicular area, and nonfascicular (connective tissue) area were determined from the metacarpophalangeal to the distal interphalangeal joint in another 35 axial nerve sections to determine regional anatomic variation.

Biscyclization reactions in butadiyne- and ethyne-linked triazenes and diazenes: concerted versus stepwise coarctate cyclizations.

A series of alkyne-linked bis-2H-indazoles has been prepared by the double cyclization of ethyne- or butadiyne-linked phenyltriazene or phenyldiazene moieties. Even though there are two five-membered ring cyclizations and several triple bond shifts involved, the reactions proceed rapidly under neutral conditions with mild heating, affording the heterocycles in excellent yields. DFT calculations, in agreement with experimental observations, indicate that the reactions: (1) occur via a very short-lived carbene intermediate, (2) are concerted via an asymmetrical transition state, or (3) are even synchronous, with as many as 16 bonds that are made or broken simultaneously.