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Delimbing of harvested wood is the first step towards obtaining finished products, where it is necessary to strain after achievement of maximum efficiency in the use of raw materials and quality improvement of the obtained assortment. Herewith, high-quality cleaning and minimization of damage of tree trunks is associated to a great extent with reliable operation of the delimbing and pull-through devices of logging machines that carry out both removal of branches and technological movement of wood. An intensive blunting of delimbing knives occurs in operation of the delimbing and pull-through device. As a result, the forces spent on delimbing increase and the process of stable cutting is disrupted. Partial cutting, and with an increase in pressure on the knives their cutting into a trunk and breaking out of limb occur, which reduce the quality of the harvested wood and lead to further intensification of wearing out of the cutting devices. The wearing out of knives is due to the action of a complex set of mechanical, chemical, temperature and other factors that accompany the technological process. This leads to a change in the dimensions of knife cutting edges. In order to improve the quality of delimbing and at that reduce the energy consumption, it is necessary to assess the influence of geometric and physico-chemical parameters of the cutting knives on their wear resistance, which will allow to theoretically justify the rational geometry of the cutting wedge and requirements for the physico-chemical characteristics of the recommended materials. The force interaction analysis of the cutting wedge with the cut limb has shown that, already at the beginning of the contact, the cutting blade is acted by the shock bending load, which, when peak values are reached, often leads to wearing out by chipping of sufficiently large microvolumes of the cutting edge. In this case, the wearing out of delimbing knives occurs mainly due to thedevelopment of microcracks, which are formed as a result of anti-plane deformation when applying stresses, and depends on the parameters of brittle crushing of materials. Moreover, the wearing out becomes more intense with contact with contaminated and wet, and in winter period frozen wood, which leads to intensification of corrosion and mechanical processes in the marginal areas of knife blades. The solution of the problem of increasing the wear resistance of delimbing knives can be provided by optimization of dimensions of knife wedge and formation of favorable physical and mechanical characteristics in the surface layer that minimize the wear intensity. The favorable dimensions of knife wedge were experimentally determined for this purpose. Complex alloyed chromium-nickel steel and rational modes of its heat treatment are proposed for the manufacture of delimbing knifes. Electrodeposition hardening is recommended as the surface treatment, which allows to optimize the surface roughness and form a favorable compressive stress in the marginal areas, thus providing high wear resistance of delimbing knives.For citation: Pilyushina G.A., Pamfilov E.A., Sheveleva E.V. Wear Resistance Improvement of Delimbing Knives of Multifunctional Logging Machines. Lesnoy Zhurnal [Russian Forestry Journal], 2019, no. 6, pp. 174–184. DOI: 10.17238/issn0536-1036.2019.6.174

Background: The presence of retained foreign bodies in the spinal canal has been reported in the literature. They are attributed to retained pieces of medical equipment after surgery, or, following trauma, to residual bullets, glass fragments, or knife blades. Although some retained materials do not cause any neurological deficits in the short run, others may become symptomatic months later. Case Description: A 2-year-old male presented with a history of intermittent fever and mild lower extremity weakness. Notably, the original infectious workup was negative. However, a noncontrast CT scan later documented a needle-shaped foreign body in the spinal canal at the T10 level. During the T10 laminectomy, a needle (i.e. from a medical syringe) was removed, the patient remained neurologically intact. The foreign body turned out to be a medical syringe needle tip. Conclusion: A 2-year-old male presented with fevers and mild lower extremity weakness attributed to an intraspinal needle tip found utilizing CT at the T10 level. T10 laminectomy allowed for removal of a small needle tip. This shows the importance of removing retained spinal foreign bodies to avoid further/future neurological injury, and/or the potential risks/complications of foreign body migration/sequestration.

Detailed information on skeletal trauma analysis of burned bone is important to ascertain the manner and cause of death in forensic casework. This research used three different knife types, one with a non-serrated blade, one a fine-serrated blade, and one a coarse-serrated blade, to inflict trauma to manually macerated Sus scrofa ribs (n = 240), and these ribs were later exposed to heat. Qualitative and quantitative analyses were conducted using macroscopic and microscopic techniques to assess specific characteristics of the cut marks. Differences in cut mark dimension and morphology of the ribs were investigated. After heat exposure, the cut marks on the rib samples remained recognisable and did not alter considerably. A level of dimensional and morphological preservation was reliant on the cutting action and the features of the knife blade as well as surrounding bone injury. The cut marks inflicted by the non-serrated blade remained recognisable despite exposure to the burning process. However, the cut marks inflicted by the coarse-serrated blade were likely to change significantly when exposed to heat. This study leads to two important results: (1) identification of pre-existing cut marks prior to heat exposure is possible in reconstructed burned bone fragments, and (2) cut marks from different types of knife blades showed dissimilar responses to heat. The outcomes obtained in this study stressed the need to adopt great care with the effects of heat on skeletal trauma analysis.

Edged weapons are frequently used to commit violent crimes (e.g., homicides, assaults or sequestrations). Following a stabbing, a fibre transfer might occur from the damaged fabric to the blade. It is crucial to investigate whether the target fibres were transferred to the blade as a result of the stabbing and if they are in association with the offence or whether they originate from another unrelated event (i.e., part of the background). The aim of this study is to explore the background population of fibres recovered on knife blades (police seizures and everyday knives) to help the interpretation of the results stemming from the analysis of the fibre evidence in crime cases involving the use of a bladed weapon. A population study was carried out to learn about the variety, the distribution and the size of the fibre population present on knife blades. After recovery using tapes lifting, stereoscopic examinations were performed to classify around 1500 fibres according to their colour and generic type. The most common colour/type combinations were: colourless/white cotton (31%), blue cotton (16%) and grey cotton fibres (11%). As blue fibres represent one of the most common colour group, they were selected to carry out a colour block study (based on microscopy observations and microspectrophotometry UV-vis spectra) to investigate the number and the size of the groups of indistinguishable fibres present on each blade. Only 30% of the knife blades presented more than one blue cotton fibre. The number of groups found per knife varied between 1 and 3, each group containing between 2 and 6 fibres. Findings revealed an important difference between the background fibre populations in terms of quantity of fibres, their morphology and spatial distributions - and the population of fibres transferred in a stabbing. The collected data can be used in a Bayesian approach to help with the interpretation of results.

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link. 10.1016/j.scijus.2020.08.002. Bladed weapons are frequently encountered in violent crime offences including street based and armed robberies, murder, sexual assaults and terrorism. A study was conducted involving four frequently encountered clothing fabrics: t-shirt (knitted cotton), denim jeans (twill woven cotton), long sleeved top (knitted synthetic blend), and skirt (non-woven faux leather) and five knives to investigate any damage resulting from a downward stabbing motion, with 300 stabs in total. Any resultant penetrating severance damage was then photographed, measured and analysed. Statistical analysis revealed significant differences between the stab hole size and shape, as a consequence of the design of a bladed weapon (in particular, the tip shape) that caused it. There is a notable correlation between the Assure knife (rounded tip) and no resulting severance damage, as the fabric surfaces were not breached with this knife. This suggests a clear alternative to pointed tip knife blades. These findings will be of interest to investigators of knife crime offences, crime-reduction units, knife manufacturers and practitioners, who share the goal of identifying a safer alternative to conventional knife blade design.

Background Bovine digital dermatitis (BDD) is a painful infectious foot disease of cattle, and much evidence implicates a pathogenic role for treponemes. This study measured the survival of BDD treponemes on hoof knife blades and tested the efficacy of relevant disinfectants under laboratory conditions. Methods Two strains of BDD treponemes were applied to hoof knife blades under aerobic conditions. Swabs were taken at different time points (10 minutes, one hour, two hours, four hours and 18 hours) and again after 20-second disinfection time with one of five disinfectants. Swabs were used directly for nested PCR to detect treponemes or inoculated for anaerobic growth, and subsequently examined using phase contrast microscopy and PCR. Results BDD treponeme DNA was detectable by nested PCR at all survival time points, and these organisms were culturable from hoof knives for two hours after exposure under aerobic conditions in the laboratory. Three of the five disinfectants—1 per cent volume per volume (v/v) FAM30®, 2 per cent weight per volume (w/v) Virkon® or 2 per cent (v/v) sodium hypochlorite—were effective at preventing visible growth of treponemes following 20-seconds contact, and 1 per cent (v/v) FAM30® also prevented detection of treponemes by PCR. Conclusion Treponeme viability of two hours under aerobic conditions suggests BDD treponemes could be transmitted between cows on hoof knives. It is therefore important to apply a disinfection protocol during foot-trimming; the authors have identified three common disinfectants that may be suitable.

Tool marks on bones induced by knife blades can be analysed morphometrically in order to enable an allocation of the suspected "inflicting weapon" to the particular morphology of the bone lesions. Until now, geometric morphometrics has not been used to analyse the morphology of knife lesions on fleshed bones in detail. By using twelve experimental knives and a drop weight tower, stab/cut injuries were inflicted on untreated pig ribs. The morphology of the experimentally produced lesions was subsequently recorded with three imaging techniques (μCT, macro photography and SEM) and analysed with different morphometric software (Amira, tps and Morpheus). Based on the measured distances between the walls of the kerf marks, which corresponded to the thickness of the blade, one could conclude to the respective blade thickness with a deviation of max. ±0.35mm and match the injuries to the knives. With subsequent reanalysis after maceration, an average shrinkage factor up to 8.6% was observed. Among the three imaging techniques used in this study, μCT was the most accurate and efficient technique, particularly because it represented the only non-destructive modality to document injuries without maceration, even though μCT is more expensive and time-consuming as well as less accessible than a macro SLR-camera or a SEM. For optimal characterizations of the blades' and kerfs' shapes the software tps proofed to be the best choice. Accordingly, geometric morphometrics could serve as a tool in forensic investigations concerning kerf marks.

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Unpacked cut chicken meat in retailis is intensely influenced by micro-environment. The aim of this paper is to determine closer the risks that exist in retail. The existing microbiological risk is determined by taking swabs from worker's hands, equipment and tools which came in direct contact with meat during work. The swabs were taken monthly during the two year period, in total number of 576. Swabs were tested by standard SRPS ISO methods:4833:2008 for determining aerobic colony count; 6888- 1:2009 for determining coagulase positive staphylococci; 16649-2:2008 for determining Escherichia coli; 15213:2011 for determining sulfitereducting clostridia and 6579:2008 for determining Salmonella spp. In 30% of the total number of taken swabs inadequate results were obtained, by category: 80% inadequate results of plastic sacs used for servicing the customers, 67% of the trenchers in shower cases, 33% of the worker's hands, 12% of the plastic meat cutting boards, 10% of meat grabbers and 9% of knife blades. The obtained results can be used to determine more closely the critical points of process steps in defining the standard operational and hygienic procedures for poultry meat handling in retail. Obtained results also can be used in risk analysis operation in retail sale of cut unpacked poultry meat.

Knives are among the weapons most frequently involved in criminal cases. They represent the most encountered category of weapons in Swiss homicide cases (completed and attempted homicides considered) and are also frequently employed in assault cases, notably bodily injuries. Whenever a knife is involved in a stabbing event, DNA and fingerprints may be sought. When garments are damaged, fibres can also be investigated. Fibres from the victim's garments might transfer onto the blade of the knife used in the assault and can thus provide useful information to determine whether a particular weapon could have be used to stab the victim. This study simulates vertical stabbings into garments with the use of a special holding device. Different types of knives and blades straight or serrated were used as weapons. Two garments presenting different shedding capacities and garment structures were also considered for the simulations. The distribution of fibres transferred onto the blade (number and position) was recorded for each simulation performed. Sequences of stabbings into the two garments were also carried out to assess whether the order of the stabs could be determined. Several parameters were considered, notably the distribution of fibres transferred onto the blade. The transfer of fibres inside the stab damage ballistic soap was used in this study and on the area near the second damage was also investigated. This study provides new insight into the interpretation of fibres transferred onto knives after a single stab or a sequence of stabbings and into determining the stabbing sequence. Finally, the study brings some guidelines for the search and recovery of fibres on the crime scene and on the blades of knives.

A 1-year study was carried out to investigate the prevalence of Salmonella in two abattoir environments coded "A" and "B" in Gaborone, Botswana. The total number of environmental samples collected from abattoirs A and B was 250 and 300, respectively. The samples were taken from soils in the corrals, knife blades, saw blades, cattle-drinking water, cattle feces, and feed. Preenrichment, enrichment, and selective/differential media, which enabled the favorable growth of Salmonella, were used in the study. Salmonellae were present in all sampled environments. The most common serotypes found in the environment at abattoir A were E1, C1, C2, and B. Serotypes B, C1, C2, C3, and E1 were common in abattoir B. Antigenic characterization of the salmonellae isolates showed that Salmonella Anatum, Salmonella Azteca, Salmonella Saintpaul, Salmonella Cerro, and Salmonella Westhampton were predominant in abattoir A, whereas Salmonella Anatum, Salmonella Mbandaka, Salmonella Molade, Salmonella Reading, and Salmonella Oranienburg were dominant in abattoir B. Implementing hazard analysis critical control point principles in work procedures would definitely reduce the gross contamination taking place in abattoirs.

Methicillin-resistant Staphylococcus aureus (MRSA) is a pathogen that has developed resistance to beta-lactam antibiotics and has been isolated at low population numbers in retail meat products. The objectives of this study were to estimate the potential transfer of MRSA from contaminated retail pork products to food contact surfaces and to estimate the potential for human exposure to MRSA by contact with those contaminated surfaces. Pork loins, bacon, and fresh pork sausage were inoculated with a four-strain mixed MRSA culture over a range of populations from approximately 4 to 8 log, vacuum packaged, and stored for 2 weeks at 5°C to simulate normal packaging and distribution. Primary transfer was determined by placing inoculated products on knife blades, cutting boards, and a human skin model (pork skin) for 5 min. Secondary transfer was determined by placing an inoculated product on the contact surface, removing it, and then placing the secondary contact surface on the initial contact surface. A pork skin model was used to simulate transfer to human skin by placing it into contact with the contact surface. The percentages of transfer for primary transfer from the inoculated products to the cutting board ranged from 39 to 49%, while the percentages of transfer to the knife ranged from 17 to 42%. The percentages of transfer from the inoculated products to the pork skin ranged from 26 to 36%. The secondary transfer percentages ranged from 2.2 to 5.2% across all products and contact surfaces. Statistical analysis showed no significant differences in the amounts of transfer between transfer surfaces and across cell concentrations.

An experimental apparatus has been built that provides information on forces associated with slitting plastic films. The apparatus uses commercially available scissors as an analogue to the counter-rotating knife blades used in industry. Cutting forces were measured using sharp and worn blades at a range of slitting speeds from 0.05–2.5 m s−1. Two important film-base materials were studied; the first was polyethylene terephthalate (PET) and the second, acetal butylate. The influences of speed and knife-edge radius were measured for each base material. For the PET-based film, the forces increased as the blade became dull and decreased with cutting speed. At low speeds, the force required to cut the acetal butylate film was independent of speed, but a sharp decrease in force was observed at a speed that depended upon the blade sharpness. An empirical model for the slitting process has been developed that can estimate the forces measured.

In response to continued concerns regarding Listeria cross-contamination during the slicing of deli meats, a series of specially prepared grade 304 and 316 stainless steel kitchen knife blades was inoculated with a six-strain Listeria monocytogenes cocktail (10(8), 10(5), and 10(3) CFU per blade) composed of two weak, two medium, and two strong biofilm-forming strains. The blades were then attached to an Instron 5565 electromechanical compression analyzer and used to slice whole chubs of delicatessen turkey breast, bologna, and salami to entirety (30 slices) at a cutting speed of 8.3 mm/s. Homogenates of the slices in University of Vermont Medium were surface or pour plated with modified Oxford agar and then enriched. Listeria transfer from knife blades inoculated at 10(8) CFU per blade was logarithmic, with a 2-log decrease seen after 8 to 12 slices and direct counts obtained thereafter out to 30 slices. However, blades containing 10(5) and 10(3) CFU per blade typically yielded direct counts out to only 20 and 5 slices, respectively. Normalizing data on a log scale for the first 10 slices resulted in significantly greater Listeria transfer and "tailing" from grade 304 as opposed to grade 316 stainless (P0.05) for all three products. After 1 year of use, surface roughness values as determined by surface profilometry were significantly greater (P0.001) for grade 304 than for grade 316 stainless blades. Cutting force and blade sharpness were not significantly different (P0.05) within stainless steel grade (P0.05) for each product. However, significant differences in cutting force were seen between salami and turkey (P0.05) for grades 304 and 316 stainless, respectively. In addition to compositional differences in the deli meats and knife blades, wear and scoring on the blade likely affected Listeria transfer during slicing.

Objective. To describe cases of intra-orbital knife blade foreign body following stabs to the orbit, together with a novel technique for removal. Methods. Retrospective case series of 3 patients. Results. All 3 patients had knife blades embedded in the orbit as a result of assault. The blades assumed the same direction within the orbit with varying degrees of depth, one causing serious vascular injury. In 2 cases the globes were intact after foreign body removal, with good visual outcomes. The third patient required enucleation. Two of the 3 knife blades were removed using a ‘double bone nibbler’ technique. The third was embedded without a handle and required removal with minor manipulation of the globe. Conclusions. Thorough investigation for vascular injury must be done before any attempted surgical removal. Visual outcomes can be good after removal of a knife blade foreign body. The double bone nibbler technique is promising for the controlled removal of embedded blades that are rigidly fixed.

During the 1978 and 1979 field seasons in the Bache Peninsula region on the east coast of Ellesmere Island ... a number of artifacts mostly of European manufacture and presumably related to Norse activities was located in old Thule culture winter house ruins. The finds were made on three sites in the study area ... Skraeling Island (Chain mail sections, knife blades, boat rivets, iron point and copper pieces, woolen cloth), the Eskimobyen site on Knud Peninsula (barrel bottom, box section, copper piece), and Haa Island (ivory figurine). A general description of these finds, locational data, associated radiocarbon dates and material analyses are presented. ...

In the Laryngoscope , January, 1914, I described a brain explorer consisting essentially of two knife blades held together with a spring, to be used in cases of suspected brain abscess in place of the exploring needle or scalpel. As is well known, each of the latter instruments may pass through the wall of an abscess, and either on account of thickness of the wall or thickness of the pus, may not reveal its presence. The practice of passing in dressing forceps and opening them here and there in the brain can hardly be called either accurate or elegant. With this brain explorer, one passes the instrument into the brain as far as one thinks necessary, and then opens the blades; if no pus escapes, they are closed and passed on, being opened from time to time until they have gone as far as is permissible in any given direction. One

An improved ultrasonically vibrated surgical cutting instrument for cutting soft tissues without stretching the same during the cutting hereof having an ultrasonic frequency generator, a transducer connected to said ultrasonic frequency generator for creating a vibratory motion and having a vibrator in communication with the transducer, and a double blade knife with one of the blades adapted to move in a longitudinal direction along the motion of the vibrator and the other blade fixed to prevent deflection of the cutting blade during the cutting operation and retaining the tissue against the cutting edge such that when the sharp edge of the knife blades touch soft tissues the knife blades will cut the soft tissues without stretching the membrane.

THE season for exhibitions in Oriental art is indeed by no means over although spring is approaching; the Oriental galleries have a number of interesting exhibits and a number of exceptional specimens of Asiatic art on display.Of current interest because of the widespread news and periodical articles, as well as because of their aesthetic quality and archaeological importance, are the Luristan bronzes at the Heeramaneck galleries. This gallery has a recently arrived collection of about twenty of these bronzes, including harness trappings, pole arms with animal and human forms interrelated in conventionalized and striking design. Included in the collection are also some weapons, such as daggers and knife blades. The problems of the culture and date of these bronzes is still disputed, though they are said to be related in some respects with Hittite culture and with Scythian and Archaemenian cultures. These bronzes may date between 550 and 330 B.C. The forthcoming publication of Professor Rostovzeff will und...