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Burn diagnosis using laser speckle light typically employs widefield illumination of the burn region to produce two-dimensional speckle patterns from light backscattered from the entire irradiated tissue volume. Analysis of speckle contrast in these time-integrated patterns can then provide information on burn severity. Here, by contrast, we use point illumination to generate diffuse reflectance laser speckle patterns of the burn. By examining spatiotemporal fluctuations in these time-integrated patterns along the radial direction from the incident point beam, we show the ability to distinguish partial-thickness burns in a porcine model in vivo within the first 24 hours post-burn. Furthermore, our findings suggest that time-integrated diffuse reflectance laser speckle can be useful for monitoring burn healing over time post-burn. Unlike conventional diffuse reflectance laser speckle detection systems that utilize scientific or industrial-grade cameras, our system is designed with a camera-phone, demonstrating the potential for burn diagnosis with a simple imager.

Objective:To compare the efficacy and safety of negatively-charged polystyrene microspheres (NCM) with controls (saline soaks) in the treatment of hard-to-heal wounds of various aetiologies.Method:Patients with one or more hard-to-heal wounds, defined as refractory to healing for at least 4 weeks, or those with exposed bone, tendon or ligament, were eligible for inclusion and were randomised to either NCM (PolyHeal; MediWound Ltd.) or controls, both applied twice daily for 4 weeks. Patients were monitored bi-weekly for an additional 8 weeks, while treated by standard wound care, at the investigators' discretion, and were re-evaluated 2 years after inclusion. The primary endpoint was defined as coverage of > 75% of the wound area by light-red granulation tissue after 4 weeks of treatment.Results:Fifty-eight patients completed the study, 32 in the NCM group and 26 in the control group. The two most common wound types were those with primary etiologies of venous insufficiency and post operative/post trauma. In the NCM group 47% of patients achieved > 75% light red granulation tissue after 4 weeks compared with 15% of patients in the control group (p=0.01). The mean wound surface area in the NCM group was reduced by 39.0% after 4 weeks compared with 14.9% in the control group (p=0.02). The achievement of > 75% light red granulation tissue and reduction of mean wound surface area was also observed in the two main sub-groups (venous insufficiency and postoperative/post trauma), although it was not statistically significant, possibly due to the small sample size in each sub-group.Conclusion:This study demonstrates that compared to control treatment, NCM treatment of hard-to-heal and chronic wounds improves formation of healthy granulation tissue and reduces wound size thus in fact ‘kick-starting’ the healing process and ‘dechronifying’ chronic wounds.Declaration of interest:This study was conducted with financial support from Polyheal Ltd. D. Vigoda and Y. Barnea received honorarium for their contribution to the study. Y. Shoham and Y. Barnea are paid consultants for MediWound Ltd. and Polyheal Ltd., respectively. J. Govrin-Yehudain is a board member of MediWound Ltd. and Polyheal Ltd.

The crystal structure of a family‐III cellulose‐binding domain (CBD) from the cellulosomal scaffoldin subunit of Clostridium thermocellum has been determined at 1.75 A resolution. The protein forms a nine‐stranded beta sandwich with a jelly roll topology and binds a calcium ion. conserved, surface‐exposed residues map into two defined surfaces located on opposite sides of the molecule. One of these faces is dominated by a planar linear strip of aromatic and polar residues which are proposed to interact with crystalline cellulose. The other conserved residues are contained in a shallow groove, the function of which is currently unknown, and which has not been observed previously in other families of CBDs. On the basis of modeling studies combined with comparisons of recently determined NMR structures for other CBDs, a general model for the binding of CBDs to cellulose is presented. Although the proposed binding of the CBD to cellulose is essentially a surface interaction, specific types and combinations of amino acids appear to interact selectively with glucose moieties positioned on three adjacent chains of the cellulose surface. The major interaction is characterized by the planar strip of aromatic residues, which align along one of the chains. In addition, polar amino acid residues are proposed to anchor the CBD molecule to two other adjacent chains of crystalline cellulose.

The crystal structure of a family‐III cellulose‐binding domain (CBD) from the cellulosomal scaffoldin subunit of Clostridium thermocellum has been determined at 1.75 A resolution. The protein forms a nine‐stranded beta sandwich with a jelly roll topology and binds a calcium ion. conserved, surface‐exposed residues map into two defined surfaces located on opposite sides of the molecule. One of these faces is dominated by a planar linear strip of aromatic and polar residues which are proposed to interact with crystalline cellulose. The other conserved residues are contained in a shallow groove, the function of which is currently unknown, and which has not been observed previously in other families of CBDs. On the basis of modeling studies combined with comparisons of recently determined NMR structures for other CBDs, a general model for the binding of CBDs to cellulose is presented. Although the proposed binding of the CBD to cellulose is essentially a surface interaction, specific types and combinations of amino acids appear to interact selectively with glucose moieties positioned on three adjacent chains of the cellulose surface. The major interaction is characterized by the planar strip of aromatic residues, which align along one of the chains. In addition, polar amino acid residues are proposed to anchor the CBD molecule to two other adjacent chains of crystalline cellulose.

Bacillus stearothermophilus T-6 produces an extracellular thermostable xylanase that can bleach paper pulp optimally at 60°C and pH 9.0. We developed an efficient method for purifying the enzyme from the cell broth by using successive steps of batch adsorption on the cellulosic cation exchanger SE-52. The optimal pH values for adsorption and elution are 5.5 and 9 respectively. The conductivity of the cell broth should remain below 7 mS/cm2 and the suitable temperature range for adsorption is 15–60°C. The adsorption parameters are: maximum capacity, 118 mg enzyme/g adsorbent; dissociation constant, 0.6 mg/ml; partition coefficient 0.988. On the basis of these results, a large-scale (12 000 l) purification process was carried out resulting in a 55% final yield and over 95% pure enzyme.

The present study deals with the mechanism by which plasmid pCED3 interferes with the growth of Bacillus subtilis. Plasmid pCED3 was constructed from pUB110 and pBR322 and contains the lacZ gene attached to the B. subtilis tmspromoter. Plasmid derivatives that contain mutations in the tmspromoter were used to examine the effect of promoter strength on cell growth, plasmid stability, the amount of plasmid DNA per cell and the activities of plasmid-encoded enzymes, i. e., β-galactosidase and kanamycin nucleotidyltransferase (KNT). Efficient lacZ transcription directed from the tmspromoter resulted in reduction in growth rate and plasmid stability without an increase in β-galactosidase activity. The amount of plasmid DNA varied between 6.6 and 12.9 pmol per mg cell protein and showed no clear correlation with the strength of the tmspromoter. Transcription from the tmspromoter inhibited the expression of the plasmid-encoded kanamycin resistance gene resulting in the reduction of both β-galactosidase activity and growth rate in the presence of kanamycin. These results suggest that the negative effect on B. subtilisgrowth exerted by pCED3 results at least partly from a decrease in kanamycin resistance by plasmid-bearing cells.

Several seamounts in the Ionian Sea, the largest unit in the eastern Mediterranean, have magnetic anomalies. The magnetization vectors of six of these seamounts have been calculated. These paleomagnetic data suggest that the Ionian Sea is composed of several crustal units which came to their present location from different directions. This implies that there has been relative motion in the past between various land masses around the Ionian Sea. The possibility that the Ionian Sea is composed of several crustal units is supported by observations of the magnetic field over the area which is of different character in the north and south. The major limitation in applying the paleomagnetic data into an evolutionary scheme is that all the seamounts in the Ionian Sea as well as its crust are undated.

The extracellular thermostable xylanase (XT‐6) produced by the thermophilic bacterium Bacillus stearothermophilusT‐6 was shown to bleach pulp optimally at pH 9 and 338 K, and was successfully used in a large‐scale biobleaching mill trial. The xylanase gene was cloned and sequenced. The mature enzyme consists of 379 amino acids with a calculated molecular weight of 43 808 and pIof 9.0. Crystallographic studies of XT‐6 were initiated to study the mechanism of catalysis as well as to provide a structural basis for rational introduction of enhanced thermostability by site‐specific mutagenesis. This report describes the crystallization and preliminary crystallographic characterization of the native XT‐6 enzyme. The most suitable crystals were obtained by the vapor‐diffusion method using ammonium sulfate and 2‐methyl‐2,4‐pentanediol as an organic additive. The crystals belong to a primitive trigonal crystal system (space group P31or P32) with room‐temperature cell dimensions of a= b= 114.9 and c= 122.6 Å. At 103 K the volume of the unit cell decreased significantly with observed dimensions of a= b= 112.2 and c= 122.9 Å. These crystals are mechanically strong and diffract X‐rays to better than 2.2 Å resolution. The crystals exhibit considerable radiation damage at room temperature even at relatively short exposures to X‐rays. A full 2.3 Å resolution diffraction data set (99.8% completeness) has recently been collected on flash‐frozen crystals at 103 K using synchrotron radiation. Two derivatives of XT‐6 were recently prepared. In the first derivative, a unique Cys residue replaced Glu265, the putative nucleophile in the active site. The second derivative was selenomethionyl xylanase which was produced biosynthetically. These derivatives have been crystallized and the resulting crystals were shown to be isomorphous to the native crystals and diffract X‐rays to comparable resolutions.

Emulsan, the polyanionic emulsifying agent synthesized by Acinetobacter calcoaceticus RAG-1, was depolymerized by an enzyme obtained from a soil bacterium YUV-1. The extracellular emulsan depolymerase was produced when strains RAG-1 and YUV-1 were grown together on agar medium. The enzyme was extracted from the agar and concentrated by ultrafiltration and ammonium sulfate precipitation. The molecular weight of the enzyme was estimated to be 89,000. Emulsan depolymerase activity was due to an eliminase reaction which split glycosidic linkages within the heteropolysaccharide backbone of emulsan to generate reducing groups and alpha, beta-unsaturated uronides with an absorbance maximum of 233 nm. Deesterified emulsan was degraded by emulsan depolymerase at only 27% of the rate of the native polymer. The treatment of emulsan solutions with emulsan depolymerase for brief periods caused a rapid and parallel drop in viscosity and emulsifying activity. More than 75% of the viscosity and emulsifying activity was lost at a time when less than 0.5% of the glycosidic linkages were broken. These data indicate that (i) emulsan depolymerase is an endoglycosidase and (ii) the higher the molecular weight of emulsan, the greater its emulsifying activity. Exhaustive digestion of emulsan with emulsan depolymerase produced oligosaccharides with a number average molecular weight of about 3,000. The fractionation of the digest on Bio-Gel P-6 yielded four broad peaks. The pooled fractions from each of the peaks contained the same relative amounts of reducing sugar and had an absorbance at 233 nm. The molar ratio of esterified sugar to reducing groups was close to 2 in each fraction.

This paper shows methods for calculating the partial derivatives of various components of the impedance tensor observable at the free surface, with respect to several components of the conductivity at different depths within the model, and with respect to the thicknesses of different sublayers, for a structure consisting of a stack of sublayers overlying a homogeneous half-space. The structure may contain isotropic and non-isotropic layers. For illustration we calculated the resolution and information matrices as well as the trade-off curve derived from the partial derivatives for a structure having high conductivity at some depth.

A geophysical inversion procedure based on the generalized inversion of a matrix is presented and applied to anisotropic magnetotelluric data for one-dimensional models. Various computational aspects of the iterative process involved are discussed together with the use of the resolution matrix, information matrix and the eigenvalues and eigenvectors for establishing the global significance of the parameters and their relationship with the data. A starting anisotropic model is built gradually, the first stage consisting of two separated isotropic problems corresponding to the off-diagonal elements of the impedance-tensor. The examples given include an anisotropic model as well as a model having two anisotropic layers and an isotropic one.