Nylon Rope Research Articles

Incomplete decapitation in suicidal hanging – Report of a case and review of the literature

Complete or incomplete decapitation is an unusual complication of suicidal hanging. We present a case of incomplete decapitation due to hanging with soft tissue injuries, spinal cord dissection between C2 and C3, fracture of the hyoid bone and injuries of cartilages. The 52-year-old male victim with a 95 kg body mass used a 1.5 cm thick and 3.1 m long nylon rope snap-hooked to a rafter. The comprehensive literature review of incomplete or complete decapitation by suicidal hanging emphasises the importance of investigation of biomechanical process. In the presented case we calculated the physical parameters (final speed: 7.8 m/s, kinetic energy: 2945 J, force: 9500 N). The previous observations were confirmed that body weight and falling distance were the most important factors in the pathomechanism of decapitation. In the hanging process energy can be stored by changing the position of the human body in the gravitational field, by changing the shape of the hanging rope and by changing the motion of the hanging body. We concluded that the occurrence of complete or incomplete decapitation can increase by the increasing energy stored as potential energy at the starting position and the characteristics of the rope extended by the hanging body.

Acoustic backscatter from a diving dolphin

The acoustic backscatter of a diving Atlantic bottlenose dolphin (Tursiops truncatus) was measured using Simrad EK-60 echosounders operating at 70, 120, and 200 kHz. The animal was trained to dive to a small platform suspended with a nylon rope from a small boat to various depths, with the maximum depth being 100 m. When the dolphin reached the platform, it was required to station on a bite plate attached to the platform until an acoustic signal was sent to release the animal. A video camera on the platform with the signal sent up on a separate line was used to monitor the animal on the bite plate. A time-depth recorder was also attached to the dolphin to determine the average rate of decent and ascent. Echosounding records were collected while the dolphin descended to and ascended from the platform. A total of 15 echosounding records with the dolphin swimming within the beam of the transducers were collected. Preliminary analysis of the data indicated that target strength varied from about −26 dB to −40 dB with a slight frequency dependency. The echoes from the dolphin were structured with the maximum echoes originating from the vicinity of the lungs.

ATTRACTION OF GRAVID ANOPHELES PSEUDOPUNCTIPENNIS FEMALES TO OVIPOSITION SUBSTRATES BY SPIROGYRA MAJUSCULA (ZYGNEMATALES: ZYGNMATACEAE) ALGAE UNDER LABORATORY CONDITIONS

The attraction of Anopheles pseudopunctipennis gravid females to oviposition substrates containing Spirogyra majuscula algae was investigated under laboratory conditions. Gravid females deposited significantly more eggs in cups containing natural algae in water from breeding sites than in cups containing artificial (nylon rope) life-like algae in water from the corresponding natural breeding site, or in cups containing natural algae in distilled water. Bioassays with Spirogyra majuscula organic extracts indicated that these extracts at concentrations of 0.1%, 0.01%, and 0.001% attracted more oviposition, but concentrations of 1%, 10%, and 100% were repellent. Gas chromatography and mass spectrometry analysis of algae organic extracts revealed a mixture of ethyl acetate and hydrocarbons compounds. These results suggest that the attraction of gravid An. pseudopunctipennis to natural breeding sites containing filamentous algae is probably mediated by organic compounds released by the algae.

The mariculture potential of the Indonesian reef-dwelling sponge Callyspongia ( Euplacella) biru: Growth, survival and bioactive compounds

In the present study, the Indonesian reef-dwelling sponge Callyspongia ( Euplacella) biru de Voogd [de Voogd, N.J., 2004. Callyspongia ( Euplacella) biru spec. nov. (Porifera: Demospongiae: Haplosclerida) from Indonesia. Zool. Meded. 78, 477–483.] (Demospongiae, Callyspongiidae) was cultured for a period of 6 months at three sites in the Spermonde Archipelago, Indonesia. A total of 250 sponge cuttings of two size classes (30 and 40 mm in length) were threaded on either polyethylene or very fine nylon rope and attached to horizontal mooring systems. All sponge cuttings were photographed at regular time intervals. Survival rates were high (82%–100%) among all treatments used. Growth rates differed significantly among treatments, but did not differ significantly per location, farming method, explant size and explant position obtained from the parent sponge. The concentration of the bioactive compound amphitoxin in the cultured explants was not significantly lower than in the natural population, but the concentration did vary significantly between explants used in the different treatments, and also between the different fragments of the natural population. The high growth potential and high survival rate suggest that this sponge species is a promising candidate for further mariculture development.

Accumulation of Marine Debris on an Intertidal Beach in an Urban Park (Halifax Harbour, Nova Scotia)

Abstract This study evaluated monthly accumulation rates and types of marine debris washed ashore at a recreational beach in Point Pleasant Park, Halifax Harbour, between April and September 2005. Black Rock Beach is 70 m long and a total of 2129 marine debris items were collected and sorted, representing a mean accumulation rate of 355 (±68 SE) items month-1. The total weight of debris items was only 10.8 kg (mean 2 kg ±0.4 SE), however eighty-six percent of this debris was plastic material. The types of litter found included: tampon applicators, condoms (i.e., sewage-related debris [SRD]); plastic fast food packaging, confectionary wrappers, Styrofoam fragments, plastic bottles and caps, items of clothing, soft drink cans, cigarettes and cigarette holders (i.e., recreational or land-based debris); packing bands, nylon rope and nets (i.e., shipping- or fishing-related debris). These items were generated by recreational use of the park (52%), sewage disposal (14%) and from shipping and fishing activities (7%). It is suggested that a significant reduction in marine debris at recreational beaches may arise by improving public awareness of the environmental and aesthetic impacts of marine litter and future improvements to the municipal sewage disposal system.

A new approach to kelp mariculture in Chile: production of free-floating sporophyte seedlings from gametophyte cultures of Lessonia trabeculata and Macrocystis pyrifera

Substantial amounts of Macrocystis and Lessonia are traditionally harvested and exported from Chile as raw material for alginate. Because of intense mari culture of abalone (Haliotis ssp.), herbivorous mol luscs that feed on brown kelps, pressure on local populations of Macrocystis and Lessonia has in creased to critical levels within the past 5 years, strongly supporting eiorts to produce algae maricul tured biomass. Here, we present our results on the de velopment of new techniques for large scale kelp mariculture in Chile. We have abandoned the tradi tional technique of direct spore seeding onto inocula tion lines. Instead, we used gametophyte cultures that were manipulated to enter gametogenesis and to produce synchronous batches of 10 4 10 5 embryos. Juvenile sporophytes were cultured under perma nent aeration and agitation, £oating unattached in contamination free glass bottles up to 10 L, plexiglass cylinders and 800 L greenhouse tanks. When hold fast initials were formed at a size of 8 cm, the sporo phytes were spliced into Nylon rope fragments and transferred to the sea. Twelve months after initiation of gametogenesis in the laboratory, Macrocystis pyrifera attained14 m length and 80 kg fresh weight m � 1 line in the sea. For Lessonia trabeculata 6m onths after gametogenesis initiation, 0.25 kg fresh weight m � 1 was attained in the sea.

Demonstrating Encapsulation and Release: A New Take on Alginate Complexation and the Nylon Rope Trick

Three variations on a classroom demonstration of the encapsulation of droplets and evidence for release of the interior solution are described. The first two demonstrations mimic biocompatible applications of encapsulation. Reversible formation of capsules from aqueous solutions of sodium alginate, a negatively charged polysaccharide derived from kelp, is shown by cross-linking with Ca2+ ionsand decomplexation with monovalent ions or a chelating agent. Rapid release ofcitric acid from a complex coacervate of alginate with chitosan, a positivelycharged polysaccharide derived from oyster shells, is compared with slow releasefrom capsules strengthened with an outer membrane cross-linked with Ca2+.A third encapsulation exercise exploits the irreversible interfacial polymerizationof diamine and diacid chloride to form membranes and illustrates the detectionof diamine release from the capsule using an indicator.

Liquid-Core Capsules via Interfacial Polymerization: A Free-Radical Analogy of the Nylon Rope Trick

Liquid-core capsules have wide-ranging applications in the high-efficiency encapsulation and controlled release of drugs, dyes, enzymes, and other substrates. Their great utility has driven the rapid development of various preparation techniques. However, there remains no convenient technique for the preparation of submicrometer liquid-core capsules with shell thicknesses less than 100 nm. Here, we demonstrate a new interfacial free-radical polymerization approach for the straightforward preparation of liquid-core polymer capsules. Conceptually, this interfacial free-radical polymerization is analogous to the classical "nylon rope trick" wherein hydrophobic and hydrophilic monomers alternately copolymerize to constrain the polymerization at interfaces, but its free-radical mechanism allows precise control of initiation, which makes it possible to finely disperse the immiscible phases prior to polymerization.

Studies of the Wet Rope's Melting Damage under the Power Transmission Lines

All the phenomena have been solved about the wet rope's melting damage under the power lines. The results are as summarized below. A wet rope acts as a conductor with the same diameter on static induction under the power lines, and if the rope is grounded, the static current is induced on the rope as same as the conductor. The static induction current flowing through the wet rope increases by the ends of the rope, and the half of the induced current on whole rope flows out each end. The cause of wet rope's melting damage under the power lines originates in above-mentioned static induction current, and this damage occurs at the end of the rope which the induction current is maximum. The maximum static induction current, without melting damage to the wet rope is 1mA or less at 12mmφ nylon rope and 5mA or less at 10mmφ aramid rope under 500kV power line. The range (length of the rope, distance between the rope and the power line) on which the wet rope's melting damage occurs can be checked from Table 4 and Fig. 10.

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Sixty two Indonesian wood species were exposed to marine borers for determining their resistances. The study was conducted at Rambut Island seashore using wood samples measuring 2,5 cm by 5 cm by 30 cm. The samples were randomly arranged using nylon rope immersed in the shore and then observed after six months. Results revealed that most of the samples were completely attacked by Martesia striata Linne of the Pholadidae family, Teredo bartchi Clapp., Dicyathifer manni Wright and Bankia cieba Clench., of the Teredinidaefamily. Nine out of 62 wood species i.e. 14.5% were resistant to marine borers. Eusideroxylon zwageri T. et B., was classified as very resistant (no attack), while Diospyros celebica Bakh., Mimusops elingi L., Parinari corymbosa Miq., Tectona grandis lf, Trestania maengayi Duthii.,Trestania whiteana Griff, Vitex cofassus Reinw., and Vitex pubescens Vahl. were categorized as resistant (light attack). These nine wood species are suitable for marine constructions.

Accurate assessment of the brake torque on a rope-braked cycle ergometer

A Monark cycle ergometer is a device globally used in physiological studies to measure the work and energy levels of exercising humans. In this paper a rope-braked cycle ergometer is examined to determine accurate measures of work and power. The work done is generally assumed, by physiologists, to be the load (masses suspended in a basket to apply tension to the rope) multiplied by the distance through which a flywheel braked by the load is moved (Astrand). In this case the flywheel of the ergometer is designed such that any point on the circumference moves through 6 m for one complete revolution of the pedals. This is a simplistic approach and fails to take into account rope-brake theory and mechanical analysis of the brake mechanism. The dynamic coefficient of friction between the steel flywheel and nylon rope was determined experimentally to be 0.175. The physical dimensions of the ergometer brake system were taken and the theoretical brake torque calculated for a series of loads. It was found that this calculated brake torque was 10.8% less than the assumed brake torque. This error means that the work and power measurements obtained from the ergometer are overestimated by 10.8% for steady speed tests.

SANS from Surfactant-Treated Nylon Fibres

ABSTRACT We report preliminary results from a Small Angle Neutron Scattering (SANS) study of nylon rope fibres treated with environmentalcontaminants of the type that the fibres may experience in everyday use. Introduction Modern high performance ropes are no longer made from siselor hemp but from synthetic polymers such as nylon-6 (e.g. Perlon®, Ultramid B®, Zytel PA®, and Akulon®), nylon-6/6, polyesters, polypropylene, high-modulus polyethylene (e.g. Dyneema® or Spectra®), aramids (e.g. Twaron® orKevlar®), and more recently even liquid crystalline polymers(e.g. Vectran®).Another major difference is in the construction of the rope.Natural fibre ropes have traditionally been hawserlaid (orplaited), but modern synthetic fibre ropes have a kernmantelconstruction in which a core bundle (the kern) of coiled yarnsis encased in a woven outer sheath (the mantle), free to slipagainst the core (Figure 1).and sheath are different polymer fibres. This allows theperformance of the rope to be matched to particularapplications.Whilst the condition of the sheath is clearly easy to establish,the same is not true of the core fibres. Contemporary methodsof rope testing are reliant on destructive mechanical tests (andit has been said that the interpretation of some of the data oftenleave a great deal to be desired).

Ruminal obstruction associated with non-digestible materials in a muturu cow: a case report

A five-year-old muturu cow in a semi-intensively managed herd with advanced pregnancy suddenly became anorexic, moribund and recumbent. While in recumbency, there was abdominal distension and the animal groaned respiration. Emergency slaughter was carried on the animal within 12hours of on set of these signs. A large nylon rope and a cloth (rag) with sediments of sand were found in the rumen. The foreign bodies together with pockets of sand in the cloth weighed 1.83kg.. Semi-intensive husbandry practice does not give the animal the opportunity of optimal grazing and as such some animals develop pica which include chewing of tethering rope and geophagia. This, coupled with pregnancy in this report predisposed the animal to pica. It is concluded that only good husbandry practices nutrition and environment can eliminate reproductive loses. Management practices and environment contribute to the presence and kind of foreign bodies present in the ruminal stomach. Again, field diagnosis of the presence of ruminal foreign bodies is naturally a difficult one except where exploratory surgery is involved. KEY WORDS: Foreign bodies, rumen, muturu cow. (Nigerian Veterinary Journal: 2002 23(2): 60-64)

Decapitation in suicidal hanging — a case report with a review of the literature

We report a case of self-decapitation by suicidal hanging from a river bridge and discuss the decapitation mechanism, reviewing the literature. The torso and the head of the victim, respectively, were found apart in a river approximately 100 m and 600 m, respectively, downstream from the bridge in two days. Morphological, serological and DNA analyses confirmed their identity. Torn ligaments between the atlas and axis accompanied by fractures in the axis at the partes interarticulares were indicative of a traction force combined with anteroflexion of the head by falling from a height, and the radial pressure due to a strong, single twisted nylon rope with a slip knot was considered to have contributed considerably to the subsequent skin laceration with wavy marginal abrasions. In the reviewed literature, cervical spine fractures were described only in two of six cases, suggesting head movement at the time of decapitation.

Food Habits of Arctic Wolves in Greenland

Analysis of feces was used to determine natural prey of arctic wolves ( Canis lupus ) in Nansen Land, North Greenland (83°N, 43°W), and Hold with Hope, East Greenland (74°N, 22°W). A total of 461 feces was collected during summers 1991–1995. In Nansen Land ( n = 110), muskox ( Ovibos moschatus ) was the major food of wolves with a frequency of occurrence of 79.4%. Lemmings ( Dicrostonyx groenlandicus ) were the next most-important group with a frequency of 19.6%, followed by arctic hares ( Lepus arcticus ) at 7.5%, wolves at 0.9%, and arctic foxes ( Alopex lagopus ) at 0.9%. Plastic and nylon rope occurred in three feces, suggesting scavenging on garbage. In Hold with Hope ( n = 351), muskoxen also were the predominant prey with a frequency of 65.4%, followed by geese and other birds at 35.5%, lemmings at 10.2%, arctic hares at 2.3%, and beetles at 0.3%. Remains of garbage (paper and paint chips) occurred in one fece. Differences in availability of regional prey may best explain dissimilarity in food habits between areas, but seasonal differences in contents of feces also may be important.

Structural Modeling of Double-Braided Synthetic Fiber Ropes

This study is primarily concerned with the performance of double-braided ropes. widely used in marine applications. The mechanical properties of such ropes are ob tained by combining their structural features and the constitutive behavior of individual rope components. Emphasis in this study is on the tensile behavior of straight ropes as well as bent ropes, either an eye splice or in a continuous loop around a bollard- like pin. In the former case, precycling and water effects on the model predictions are discussed. For new small ropes, bending rigidity is negligible, so the bending effect is considered by modifying the geometry of the rope to allow for variation of helix periods and change of cross-sectional shapes from circular to elliptical ( flattened ) . For two extreme frictional conditions considered, i.e., infinite and zero friction, predictions of small nylon rope behavior agree well with experimental results for both simple tension and tension plus bending. There is less agreement for small PET ropes, par , ticularly in bending tests.

Genetic breeding and seedling raising experiments with Porphyra protoplasts

Genetic breeding and seedling raising experiments were carried out with enzymatically isolated protoplasts from vegetative cells of Porphyra. The genetic differentiation and development patterns of cells from different growth stages and different parts of the blade were studied. Several morphological mutants and pure lines were obtained after UV irradiation and colchicine treatment. Polyethylene glycol (PEG) induced interspecific protoplast fusion between P. yezoensis and P. haitanesis. The hybrid cells divided and formed callus-like cell masses, but no blade differentiation was observed. For cultivation in the sea, the protoplasts and individual cells were attached to nylon rope nets as if they were seeds. Commercial products have already been harvested from these cultivations. This technique omitted the whole process of filament culture, used manpower sparingly, and reduced production costs. It is expected that this technique might be adopted to replace the conventional cultivation method, especially the raising of Porphyra seedlings, in the near future.

A Durable, Lightweight Structure for Conducting Field Shading Experiments

A low-cost field shading structure was developed that offers durability and simplicity. The quonset-type structure uses readily available materials, including polyvinyl chloride pipe, construction-grade reinforcing bars, nylon rope, and commercial shade fabric. The total cost for a 3.0 × 6.0 × 2.4-m (width/length/height) structure that provided 47% shade was $88.00. The structure offers substantial flexibility in terms of size and degree of shading without significantly altering design. The structure was durable under a wide range of weather conditions, and the design allowed sufficient air movement to prevent a stagnant air layer from developing over the crop.

The influence of pen size on toy preference of growing pigs

Twenty-four crossbred gilts, averaging 4 weeks of age and 9.4 kg, were weighed and allotted to either a large pen with a space allowance of 0.8 m 2 per pig or a small pen with a space allowance of 0.4 m 2 per pig (12 gilts per pen). Pigs were offered four types of toys: (1) a knotted-rope (R) toy consisting of two 30.5 cm lengths of 1.27 cm diameter nylon rope tied in knots at both ends and in the center; (2) a 30.5 cm section of 1.27 cm diameter rubber hose (H); (3) a 30.5 cm long piece of brass-plated chain (C); (4) a Penn-Plax Plantation Rubber ™, hourglass-shaped, dog toy (D). Pigs were allowed 3 days to become acclimated to their surroundings prior to the introduction of the first toy. At 07:00 h on the morning of toy presentation, two identical toys were hung in each pen from the ceiling by elastic bungee cord. Play behavior was recorded by time-lapse video cameras for 12 h between 07:00 and 19:00 on each day of toy presentation. Play behavior consisted of a pig maintaining head contact with the toy for at least 10 s. Head contact included open-mouthed bites, any attempt to bite the toy, pushing/nudging the toy with the head or snout; and alertly following the toy followed by a bite, attempted bite, or push. After a 3-day period without toys, the next toy was presented to the pigs following the same procedure. This sequence of events continued until all toys had been presented to the pigs. Three days after the final toy presentation, all pigs were weighed, randomly reassigned to the two different pen sizes (12 pigs per pen), and presented with the same toys in a re-randomized order. The amount of time at least one pig in a pen played with a particular toy was recorded, as was the amount of time pigs spent on other activities, to ensure accurate measures of time. No significant ( P>0.15) pen size by toy interactions were identified; therefore, only main effect differences are reported. There was a trend for pigs in the large pen to play less ( P=0.08) than pigs in the small pen. Data indicated that pigs in the small pen group played with toys approximately 50 min more than pigs in the large pen group; however, the percentage of time spent playing with toys was unaffected ( P<0.10) by pen size. Pigs spent a greater ( P<0.05) amount of time playing with D than either R, H, or C. Moreover, pigs spent 18.96, 21.86, and 23.87% more ( P<0.05) time playing with D than R, H, and C, respectively. Pigs preferred ( P<0.05) or tended to prefer ( P≤0.12) D over other toys during the first 7 h of observation. During the eighth hour of observation, pigs spent significantly more ( P<0.05) time playing with D and R than H or C. We conclude that the addition of a soft, pliable, rubber dog toy enriches the environment of confined pigs, and could reduce or alter aggressive and stereotypic behaviors commonly associated with confinement operations.

Forming and Teaching True Knots for Strabismus Surgery

I describe a system for ensuring the formation of true knots in the locking bites in strabismus surgery. I also present a method for teaching this system to residents that makes use of a piece of cotton or nylon rope, a cotton mop refill, and the end of a garden rake.