Access to metallobacteriochlorins is essential for investigation of a wide variety of fundamental photochemical processes, yet relatively few synthetic metallobacteriochlorins have been prepared. Members of a set of synthetic bacteriochlorins bearing 0-4 carbonyl groups (1, 2, or 4 carboethoxy substituents, or an annulated imide moiety) were examined under two conditions: (i) standard conditions for zincation of porphyrins [Zn(OAc)(2)·2H(2)O in N,N-dimethylformamide (DMF) at 60-80 °C], and (ii) treatment in tetrahydrofuran (THF) with a strong base [e.g., NaH or lithium diisopropylamide (LDA)] followed by a metal reagent MX(n). Zincation of bacteriochlorins that bear 2-4 carbonyl groups proceeded under the former method whereas those with 0-2 carbonyl groups proceeded with NaH or LDA/THF followed by Zn(OTf)(2). The scope of metalation (via NaH or LDA in THF) is as follows: (a) for bacteriochlorins that bear two electron-releasing aryl groups, M = Cu, Zn, Pd, and InCl (but not Mg, Al, Ni, Sn, or Au); (b) for bacteriochlorins that bear two carboethoxy groups, M = Ni, Cu, Zn, Pd, Cd, InCl, and Sn (but not Mg, Al, or Au); and (c) a bacteriochlorin with four carboethoxy groups was metalated with Mg (other metals were not examined). Altogether, 15 metallobacteriochlorins were isolated and characterized. Single-crystal X-ray analysis of 8,8,18,18-tetramethylbacteriochlorin reveals the core geometry provided by the four nitrogen atoms is rectangular; the difference in length of the two sides is ∼0.08 Å. Electronic characteristics of (metal-free) bacteriochlorins were probed through electrochemical measurements along with density functional theory calculation of the energies of the frontier molecular orbitals. The photophysical properties (fluorescence yields, triplet yields, singlet and triplet excited-state lifetimes) of the zinc bacteriochlorins are generally similar to those of the metal-free analogues, and to those of the native chromophores bacteriochlorophyll a and bacteriopheophytin a. The availability of diverse metallobacteriochlorins should prove useful in a variety of fundamental photochemical studies and applications.

The purpose of this study was to examine the feasibility of teleconsultation using a mobile camera-phone to evaluate the severity of digital soft-tissue injury and to triage the injury with regard to management recommendations. With a built-in 110,000-pixel digital camera, pictures of the injured digit(s) or radiograph were taken by surgical residents in the emergency room and transmitted to another camera-phone to be viewed by the remote consultant surgeon. A brief medical and trauma history of each patient was relayed also by mobile phone. The consultant surgeon then reviewed all of these patients in the emergency room shortly after the initial telemedicine referral. Separate triaging for each digital injury into three groups was recorded during remote teleconsultation and according to actual treatment by the attending surgeon as follows: group I, the injury could be managed with conservative treatment, such as secondary intention wound healing, or primary closure with or without bone shortening; group II, skin grafting or local flap coverage was required for management of the injury; and group III, microsurgery such as replantation or free flap coverage was necessary to deal with the injury. Later, triaging was also performed individually by three junior plastic residents according to image review and patient referral information. Teleconsultation through a mobile camera-phone was performed for 45 patients with injuries of 81 digits from January to May of 2003. Of these 81 digital injuries, there were 12 cases (15 percent) where disagreement of triaging occurred between the teleconsultation and the actual treatment by the attending surgeon. In image reviewing, there was 79 percent sensitivity and 71 percent specificity in remote diagnosis of the skin defect and 76 percent sensitivity and 75 percent specificity in remote identification of the bone exposure regarding the concordance of opinions of all three surgeons; there was significant discordance in triaging in 20 cases (25 percent), and the difference in triaging was partly attributed to the inability to show instances of tiny exposed digital bone or tendon in some cases under the low-resolution digital image and the situation of a bloody oozing wound. In some cases, the difficulty in evaluating the probability of primary closure of severely avulsed skin edges or the probability of executing replantation for finger amputation also contributed to different triaging outcomes. Two neglected diagnoses of transected digital nerves were found and influenced triaging, highlighting the importance of on-site physical examination during teleconsultation. The telemedicine system using a mobile camera-phone based on the global system for mobile communication is feasible and valuable for early diagnosis and triaging of digital soft-tissue injury in emergency cases, with on-line verbal communication and review of the transmitted captured image. This system has the advantages of ease of use, low cost, high portability, and mobility. With advances in hardware for digital i...

The aim of this study is to investigate the structure development and growth kinetics of the interfacial structure of cold roll bonded Al/Cu bimetal sheet. An interfacial structure is developed during the annealing process. The characteristics of the constituent phases at the interface of Al/Cu bimetal are studied by means of scanning electron microscope (SEM), X-ray diffraction (XRD) and transmission electron microscope (TEM). The results indicate that an obvious multi-layers interdiffusion structure is developed at the Al/Cu interface. The diffusion layer is consisted of four intermetallic compounds; Al 2 Cu, AlCu, Al 3 Cu 4 and Al 4 Cu 9 . The growth of these intermetallics during annealing can be achieved by the diffusion process. The activation energies of Al 2 Cu, AlCu + Al 3 Cu 4 , Al 4 Cu 9 and the total intermetallic layer are found to be 97.504, 107.46, 117.52 and 107.85 kJ/mol, respectively. These intermetallics generally possess higher hardness values than those of the corresponding base metals. AlCu and Al 3 Cu 4 exhibit much higher hardness than that of Al 2 Cu and Al 4 Cu 9 , which implies lower fracture toughness. The observation of crack propagation paths shows that fracture mainly occurs in the intermetallic compound layers of AlCu and Al 3 Cu 4 , which are located between Al 2 Cu and Al 4 Cu 9 .

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Chromophores that absorb and emit in the red spectral region (600–700 nm), are water soluble, and bear a bioconjugatable tether are relatively rare yet would fulfill many applications in photochemistry and photomedicine. Here, three molecular designs have been developed wherein stable synthetic chlorins – analogues of chlorophylls – have been tailored with PEG groups for use in aqueous solution. The designs differ with regard to order of the installation (pre/post-formation of the chlorin macrocycle) and position of the PEG groups. Six PEGylated synthetic chlorins (three free bases, three zinc chelates) have been prepared, of which four are equipped with a bioconjugatable (carboxylic acid) tether. The most effective design for aqueous solubilization entails facial encumbrance where PEG groups project above and below the plane of the hydrophobic disk-like chlorin macrocycle. The chlorins possess strong absorption at ~400 nm (B band) and in the red region (Qy band); regardless of wavelength of excitation, emission occurs in the red region. Excitation in the ~400 nm region thus provides an effective Stokes shift of >200 nm. The four bioconjugatable water-soluble chlorins exhibit Qy absorption/emission in water at 613/614, 636/638, 698/700 and 706/710 nm. The spectral properties are essentially unchanged in DMF and water for the facially encumbered chlorins, which also exhibit narrow Qy absorption and emission bands (full-width-at-half maximum of each <25 nm). The water-solubility was assessed by absorption spectroscopy over the concentration range ~0.4 μM – 0.4 mM. One chlorin was conjugated to a mouse polyclonal IgG antibody for use in flow cytometry with compensation beads for proof-of-principle. The conjugate displayed a sharp signal when excited by a violet laser (405 nm) with emission in the 620–660 nm range. Taken together, the designs described herein augur well for development of a set of spectrally distinct chlorins with relatively sharp bands in the red region.

The aim of this article is to study the influence of interfacial structure development at interface on the fracture mechanism and the bond strength of cold roll bonded Al/Cu bimetal plate. The Al/Cu bimetal plates are produced by cold roll bonding and then sintered at different conditions. The bond strength of the Al/Cu bimetal plate increases generally to maximum values and then decreases to low values with increasing sintering temperature and time. Interfacial structures develop with increasing sintering temperature and time. The main interfacial layers are Al 2 Cu, AlCu, Al 3 Cu 4 and Al 4 Cu 9 . The formation and thickening of those intermetallic compounds promotes cracks propagation and weakens the bond strength of the bimetal plates. The fracture mechanism transforms from ductile to brittle cleavage with the development of interfacial structures. While the bond strength of the material starts to decrease, no obvious Kirkendall effect of void formation is observed in the present study.

The camera-phone is a feasible tool for remote evaluation regarding the replantation potential of completely amputated fingers and it holds significant promise in avoiding unnecessary patient transfer by providing useful information.

We present a highly sensitive metal enhanced fluorescence (MEF) method based on a novel silver nanostructure fabricated with Cy5-functionalized silver nanoparticles (AgNPs) and AgNO(3). The analytical performance has been demonstrated by microarray detection of streptavidin (SA) and human IgE. The fluorescence intensity can be enhanced substantially with the combined use of AgNPs and fluorescence enhanced solution (FES). Aptamers have been used for the preparation of Tag-C, which demonstrate IgE detection from 0.5 ng/mL to 16 ng/mL, and the limit of detection is determined to be 0.25 ng/mL. SEM images show nanogaps exist in the aggregated silver nanoparticles and the nanogaps allow for the trap of fluorophores in the nanostructures that emit brighter light upon excitation. The silver nanostructures formed by Tags and FES proved to be an excellent platform for MEF of fluorophores whose excitation and emission occurred between 436 nm and 1000 nm. Finite-difference time-domain (FDTD) simulation has been carried out to confirm the enhanced electromagnetic field inside silver nanostructures, leading to strong overlap/resonance coupling and eventual fluorescence enhancement.