Decrease In Breaking Strength Research Articles

Association of Ovocalyxin-32 Gene Variants with Egg Quality Traits in Indigenous Chicken Breeds.

This study sought to evaluate the genetic variations of the ovocalyxin-32 gene and its association with egg quality traits in indigenous chicken populations, focusing on exons 1 and 6. Genotype frequencies of SNPs (G/T and A/G) within these exons were assessed for their conformity to the Hardy-Weinberg equilibrium (HWE) across several strains. While most strains exhibited close adherence to HWE expectations, some like light-brown and gray strains indicated substantial discrepancies, particularly for the TT genotype, which points towards the possible effects of genetic drift as well as selection pressures. This study also analyzed the influence of such SNPs on egg quality parameters. A thinner eggshell, reduced shell weight, and decreased breaking strength were associated with the G/T SNP in exon 1, suggesting a likely negative effect on egg quality in T allele carriers. Conversely, the AG genotype displayed better performance in shell thickness, weight and egg weight in the A/G SNP in exon 1, whilst yolk height was best improved by the AA genotype compared to breaking strength. For instance, in exon 6, the A/G SNP enhanced the shell and yolk quality among AG genotypes, while the CC genotype resulted in better eggshell characteristics with enlarged yolks because the C/T SNP was linked. Nonetheless, there were no significant deviations from the HWE despite these associations, which suggested that most breeds had a stable genetic background. Further, considering SNPs' additive and dominant effects in this research, it was indicated that additive effects account for phenotypic expressions given by the G/T SNP located at exon 1. In contrast, significant additive and dominant effects were observed under the A/G SNP situated at the exon. Generally, it therefore could be concluded from this study that specific SNPs within the ovocalyxin-32 gene may act as good markers for marker-assisted selection (MAS) that can improve desired characteristics-such as those of egg quality-in indigenous chicken breeds. This study demonstrated that both additive and dominance effects must be taken into account when performing genetic analyses, thereby emphasizing the complexity of phenotypic variation caused by genetic mechanisms in native chicken races.

Effects of irrigation on stem lignin and breaking strength of winter wheat with different planting densities

Increasing planting density is an important cultivation approach to improve wheat single yield. In field production, over irrigation under densified population conditions can easily cause lodging. Therefore, the lodging resistant wheat cultivar JM22 and the lodging sensitive wheat cultivar SN16 was used as experimental materials. Two irrigation treatments [rain-fed and spring irrigation (at jointing and anthesis stage)] were set with five planting densities (150 × 104 plants ha−1, 225 × 104 plants ha−1, 300 × 104 plants ha−1, 375 × 104 plants ha−1 and 450 × 104 plants ha−1). Lignin accumulation and its monomers (guaiacyl, syringyl and p-hydroxyphenyl) in combination with the apparent and microanatomic characteristics of the basal second stems, were determined to elucidate effects of irrigation on the formation of breaking strength in wheat stems at different planting densities. The results showed that the most important factors affecting the breaking strength of stems were different in different stages and different treatments. Through multiple stepwise regression analysis, it was found that under low density (150 × 104 plants ha−1) conditions, irrigation decreased breaking strength of stem mainly by affecting lignin accumulation and its subunits. However, at medium and high density (225 × 104 plants ha−1-375 × 104 plants ha−1), the decrease of stem breaking strength caused by irrigation was the result of the co-regulation of lignin metabolism, stem microscopic and morphological characteristics. At anthesis stage, when irrigated under the condition of low density (150 × 104 plants ha−1), the content of G subunit increased by 100 μg g−1, the stem breaking strength increased by 0.4 N. At medium density (225 × 104 plants ha−1-300 × 104 plants ha−1), irrigation increased S subunit content by 100 μg g−1, which resulting in high stem breaking strength by 0.5 N. However, at high density (375 × 104 plants ha−1-450 × 104 plants ha−1), along with H subunit content was increased by 10 μg g−1, the stem breaking strength was decreased by 0.14 N. Under irrigated and densified populations conditions, the decreasing range of wall thickness (−13.53%), stem filling degree (−16.65%) and the increasing range of H monomer ratio (15.77%) of high lodging resistance varieties were lower than those of SN16. Therefore, it held better ability to resist adverse environment and maintain lodging resistance. In this experiment, on the basis of irrigation (at jointing and anthesis stage) and 25 × 104 plants ha−1 planting density resulted in the highest yield (10,325.03 kg ha−1) and moderate stem.

Study on Dispersant and Surface Analysis of Ophthalmic Lens Materials Containing Carbon Nanotubes.

In this study, two types of carbon nanotubes were used as ophthalmic material, and hydrogel contact lenses were polymerized by adding two types of dispersants to effectively exert the functions of carbon nanotubes. The physical properties and surfaces of the ophthalmic hydrogel lenses prepared to confirm the functionality as a dispersant were compared and analyzed to find the utility as an ophthalmic lens material. For the polymerization, single-walled carbon nanotubes (SWCNTs), single-walled carbon nanotubes carboxylic acid functionalized (SWCCNTs), 2-hydroxyethyl methacrylate (HEMA), ethylene glycol dimethacrylate (EGDMA, a crosslinking agent), and azobisisobutyronitrile (AIBN, an initiator) was used. In addition, as a dispersant, PVP (polyvinylpyrrolidone) and BYK-111 were copolymerized. As a result of this study, PVP increased the water content and decreased refractive index regardless of the type of carbon, whereas BYK-111 did not show a significant difference in basic properties. Also, PVP gradually decreased breaking strength, while BYK-111 gradually increased breaking strength. BYK-111 effectively exerted the function of carbon nanotubes, and it was confirmed whether it was dispersed through TEM. Therefore, if carbon nanotubes are used as ophthalmic materials by utilizing BYK-111, it considered to be used as functional ophthalmic lens materials.

Stretching and Breaking of Ultrathin 2D Hybrid Organic-Inorganic Perovskites.

Two-dimensional (2D) hybrid organic-inorganic perovskites (HOIPs) are recent members of the 2D materials family with wide tunability, highly dynamic structural features, and excellent physical properties. Ultrathin 2D HOIPs and their heterostructures with other 2D materials have been exploited for study of physical phenomena and device applications. The in-plane mechanical properties of 2D ultrathin HOIPs are critical for understanding the coupling between mechanical and other physical fields and for integrated devices applications. Here we report the in-plane mechanical properties of ultrathin freestanding 2D lead iodide perovskite membranes and their dependence on the membrane thickness. The in-plane Young's moduli of 2D HOIPs are smaller than that of conventional covalently bonded 2D materials. As the thickness increases from monolayer to three-layer, both the Young's modulus and breaking strength decrease, while three-layer and four-layer 2D HOIPs have almost identical in-plane mechanical properties. These thickness-dependent mechanical properties can be attributed to interlayer slippage during deformation. Our results show that ultrathin 2D HOIPs exhibit outstanding breaking strength/Young's modulus ratio compared to many other widely used engineering materials and polymeric flexible substrates, which renders them suitable for application into flexible electronic devices.

The effect of exfoliation and plasma application on the properties of continuous graphene oxide fiber

ABSTRACTThis study has been performed on continuous graphene oxide fiber produced by different production parameters which has very large potential application areas such as electronic/smart textiles, sensors, energy. In this study, three different graphene oxide dispersion preparation methods; namely, Modified Hummers, Modified Hummers on exfoliated graphite and Modified Hummers with plasma application; have been used to prepare coagulated continuous graphene oxide fibers. The effect of production parameters on properties of continuous graphene oxide fibers have been measured by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), X-Ray Photoelectron Microscopy (XPS), tensile tester, electrical conductivity device. It was observed that exfoliation process results with decrease of fiber Tex count, fiber surface roughness, oxygen functional groups and an increase of breaking strength and electrical conductivity, while plasma application results to an increase of surface roughness of fiber, oxygen functional groups and decrease of breaking strength of fiber.

실리콘 수지 혼합비율에 따른 Pre-form 형광체 막 특성 변화에 관한 연구

The effect of the viscosity of phosphor slurry prepared by mixing two types of sil- icone resins with different viscosities in various ratios on the properties of pre-formed phosphor films was investigated. The pre-formed phosphor films manufactured using these phosphor slurries were evaluated for curing characteristics, breaking strength, shear strength, and optical properties. The test results demonstrated that increasing the amount of high-viscosity silicone resin in the composite resin resulted in decreased curing reaction rate, decreased breaking strength, and correlated color temperature, whereas the viscosity and adhesion strength of the composite resin increased. Among seven different mixing ratios of the low- and high-viscosity silicone resins prepared for the composite resin, white- light emission was realized for the ratio 70:30, and the pre-formed phosphor film with this ratio exhibited high breaking strength and low adhesion strength. The breaking strength thus obtained was 24.0 MPa, the adhesion strength was 0.17 MPa, the color temperature was 5,650 K, and the two chromaticity coordinates (CIE(x, y) (1931)) were (0.3293, 0.3251).

Process Optimization for the Finish of PP Spunbonded Nonwovens with Photo-Catalytic Microcapsule

Microcapsules were prepared using the complex coacervation method with nanoanatase TiO2 as the core material, gelatin/Arabia gum as the wall material. Then the obtained microcapsules were finished to the PP nonwovens to investigate the photocatalytic properties to the nonwovens. The breaking strength decrease of the finished polypropylene nonwoven after irradiated with the artificial UV lamp was the optimization evaluation index, and the four factors including finishing temperature, adhesive concentration, microcapsule concentration and finishing time were used to design the experimental scheme using the second order orthogonal rotation combination design. The data were processed with SAS software, the obtained optimal finish process is: finishing temperature is 22°C, adhesive concentration is 75g/L, microcapsule concentration is 36g/L, and finishing time 25min.

Contributions of fat content and oxidation to the changes in physicochemical and sensory attributes of pork dumpling filler during frozen storage.

This study was conducted to evaluate the contributions of fat addition levels and storage duration at -18 °C to the oxidation and physicochemical changes of frozen pork dumpling filler. With an increase in the fat addition, thiobarbituric acid-reactive substances and carbonyl production increased (P < 0.05), the transition temperatures (Tmax) shifted to lower temperatures, and the total enthalpy (ΔH) of protein denaturation reduced (P < 0.05). Dynamic rheological measurements revealed a compromised viscoelastic network in filler protein gels with increased fat levels and storage time. Increasing the fat level also increased cooking loss and decreased breaking strength (P < 0.05). The sensory results showed that the dumplings with a high fat level had significantly higher texture, juiciness, and overall acceptability scores (P < 0.05). The results suggest that the dumplings with a high fat level stored for long periods enhanced oxidation and cooking loss and decreased breaking strength; however, it is important to add proper fat considering the palatability.

Effect of Melamine / Urea Modified Phenol Formaldehyde Resin Binder on the Mechanical Properties of Glass-Fiber Felt

The use of melamine / urea modified phenol formaldehyde resin binder in the glass-fiber felt has led to products with lower free formaldehyde, higher water repellency and flexibility. This study gives a detailed description of the influence on the mechanical properties of the glass-fiber using the phenol formaldehyde resin with different levels of melamine and urea. Results show that, the free formaldehyde content reduced with the increase of the amount of urea and melamine, a small molecule of melamine and urea destroy the macromolecular chain of phenol formaldehyde resin leading to the decrease of breaking strength. At the same time, the decrease of the molecular chain is accompanied by the increase of flexibility.

Gas transport properties and pervaporation performance of fluoropolymer gel membranes based on pure and mixed ionic liquids

Ionic liquid polymer gel membranes based on poly(vinylidene fluoride-co-hexafluoropropylene) (p(VDF-HFP)) were prepared by solvent casting from a solution in acetone. The membranes contain from 20wt% to 80wt% of pure or mixed ionic liquids based on the imidazolium cation: 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][TFSI]) and 1-hexadecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([HdMIM][TFSI]). Both ionic liquids have the fluorinated anion bis(trifluoromethylsulfonyl)imide, which should make them more compatible with a fluoropolymer matrix, while the different tail lengths in the cation give significantly different melting points. The thermal and mechanical properties of the blend membranes were evaluated and compared with the neat polymer. The performance of the membranes was tested in terms of pure gas permeability and selectivity, separation of limonene/carvone mixtures by pervaporation, and influence of a low water content in the feed on separation by the blended membrane.DSC analysis shows a gradual decrease of the melting point of the gel and a decrease in the overall melting enthalpy with increasing IL content, whereas the melting enthalpy normalized for the polymer fraction shows an initial drop and then a gradual increase. In the presence of the ionic liquid, the elastic modulus and break strength decrease dramatically, while the maximum deformation at first increases due to higher flexibility of the plasticized polymer and then rapidly decreases above 40wt% of IL as a consequence of the progressive decrease of the number of entanglements.The gas transport through the membranes prepared in this study was evaluated in the temperature range of 20–60°C, which includes the melting point of the high temperature ionic liquid [HdMIM][TFSI]. These permeation measurements show a significant increase of the permeability in the presence of the IL mixture, especially for carbon dioxide. This suggests a potential application in gas separation membranes, for instance for natural gas treatment or for CO2 sequestration from flue gas.

Effect of Temperature and Humidity on Mechanical Properties of Rabbit Hair Fibers

In this paper, it tests the mechanical properties of rabbit hair fibers in different temperatures and humidity. Contrast and analysis by experiment showed the temperature exerts a great influence on the tensile strain, breaking elongation, breaking force and breaking strength. In wetting condition, the tensile strain and breaking elongation increase, but the breaking force and breaking strength decrease. The rabbit hair fiber processing with too much water will make the structure easier to break and destroy.

Fabrication and characterization of dense Chitosan/polyvinyl-alcohol/poly-lactic-acid blend membranes

Dense membranes of Chitosan (CS)/Poly(vinyl alcohol) (PVA)/Poly(lactic acid) (PLA) blend were successfully fabricated using casting technique. The mechanical properties, moisture regain and water vapor permeability of polymer blend membranes were estimated by tensile test, moisture regain rate and dish method test respectively. The microstructures, morphology, chemical composition and thermal properties were also characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC) respectively. Results indicated that there were interactions and good compatibility among CS, PLA and PVA. And the blend membranes have good breaking elongation and slightly decreased breaking strength, and show best moisture regain at the case of CS60 (the content of CS in the blends is 60 %). They also have excellent porous structure, which is beneficial to their air permeability and may also contribute to cell regeneration. With the adding of PVA content, the melting peaks of blend membranes reduce and gradually close to that of PVA, demonstrating that the regularity of CS molecular chain may be destroyed and hydrogen bonds of macromolecules in polymers were newly formed. As a result, solution blending of the three polymers could complement their disadvantages and significantly improve the membrane performance of a single polymer, thus promote the mechanical and biological properties of blend membrane.

Structure and Performance in the Compacting Process of Polyacrylonitrile Fiber

As a key stage in wet spinning, compacting process served as a connection between spin and post treatment, it has significant influence on the performances of polyacrylonitrile (PAN) fiber. In this paper, the influences of temperature, time and tension on the compacting process and performance of fibers were studied. The test shows that the suitable compacting process condition is 110°C for 90s with a higher shrinkage ratio. With increasing shrinkage ratio, density and breaking elongation raise, but orientation and breaking strength decrease. To obtain better effect of compacting process, loss of orientation and breaking strength can hardly be avoided; it can be compensated by secondary draw in post process.

High Ionic Liquid Content Polymeric Gel Membranes: Preparation and Performance

Ionic liquid polymeric gel membranes containing from 20 wt % to 80 wt % of the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][TFSI]) in poly(vinylidene fluoride-co-hexafluoropropylene) (p(VDF-HFP)) were prepared by solvent casting from a solution in acetone. The effect of the ionic liquid on the performance and properties of the membranes was discussed and compared with the neat polymer. In the presence of an excess of ionic liquid, p(VDF-HFP) membranes swell in a significant way, especially above 70 °C, becoming completely soluble above 90 °C. DSC analysis shows a gradual decrease of the melting point of the gel and a decrease in the overall melting enthalpy with increasing IL content, whereas the melting enthalpy normalized for the polymer fraction shows an initial drop and then a gradual increase. In the presence of the ionic liquid, the elastic modulus and break strength decrease dramatically, while the maximum deformation first increases due to higher flexibility of the plasticized polymer and then rapidly decreases above 40 wt % of IL as a consequence of the progressive decrease of the number of entanglements. X-ray studies demonstrate a reduction in the overall crystal content. The position of the strongest diffraction peak remains unaltered in all samples, suggesting that only the polymer chains crystallize and that no cocrystallization of ionic liquid and polymer takes place. Preliminary gas permeation measurements show a significant increase of the permeability in the presence of [EMIM][TFSI], especially for carbon dioxide. This suggests a potential application in gas separation membranes, for instance for natural gas treatment or for CO2 sequestration from flue gas.

Sol–gel coating of cellulose fibres with antimicrobial and repellent properties

Multifunctional, water and oil repellent and antimicrobial finishes for cotton fibres were prepared from a commercially available fluoroalkylfunctional water-born siloxane (FAS) (Degussa), nanosized silver (Ag) (CHT) and a reactive organic–inorganic binder (RB) (CHT). Two different application procedures were used: firstly, one stage treatment of cotton fabric samples by FAS sol (i), as well as by a sol mixture constituted from all three precursors (Ag–RB–FAS, procedure 1S) (ii), and secondly, two stage treatment of cotton by Ag–RB sol and than by FAS sol (Ag–RB + FAS, procedure 2S) (iii). The hydrophobic and oleophobic properties of cotton fabrics treated by procedures (i)–(iii) before and after consecutive (up to 10) washings were established from contact angle measurements (water, diiodomethane and n-hexadecane) and correlated with infrared and XPS spectroscopic measurements. The results revealed that even after 10 washing cycles cotton treated with Ag–RB + FAS (2S) retained an oleophobicity similar to that of the FAS treated cotton, while the Ag–RB–FAS (1S) cotton fibres exhibited a loss of oleophobicity already after the second washing, even though fluorine and C–F vibrational bands were detected in the corresponding XPS and IR spectra. The antibacterial activity of cotton treated by procedures (i)–(iii) was tested by its reduction of the bacteria Escherichia coli and Staphylococcus aureus following the AATCC 100-1999 standard method and EN ISO 20743:2007 transfer method. The reduction in growth of both bacteria was nearly complete for the unwashed Ag–RB and Ag–RB–FAS (S1), but for the unwashed Ag–RB + FAS (S2) treated cotton no reduction of S. aureus and 43.5 ± 6.9% reduction of E. coli was noted. After the first washing, the latter two finishes exhibited nearly a complete reduction of E. coli but for the Ag–RB treated cotton the reduction dropped to 88.9 ± 3.4. None of the finishes retained antibacterial properties after 10 repetitive washings. The beneficial and long-lasting low surface energy effect of FAS finishes in the absence of Ag nanoparticles, which led to the “passive” antibacterial properties of FAS treated cotton fabrics, was established by applying the EN ISO 20743:2007 transfer method. The results revealed a reduction in bacteria of about 21.9 ± 5.7% (FAS), 13.1 ± 4.8% (Ag–RB–FAS (S1)) and 41.5 ± 3.7% (Ag–Rb + FAS (S2)), while no reduction of the growth of bacteria was observed for cotton treated with Ag nanoparticles after 10 repetitive washings. The physical properties (bending rigidity, breaking strength, air permeability) of finished cotton samples were determined, and showed increased fabric softness and flexibility as compared to the Ag–RB treated cotton, but a slight decrease of breaking strength in the warp and weft directions, while air permeability decreased for all type of finishes.

Biodegradability of cellulose fabric modified by imidazolidinone

The influence of modifying cellulose by imidazolidinone on its biodegradability was studied using the soil burial test and enzymatic hydrolysis. The degree of biodegradation was determined on the basis of scanning electron micrographs, tensile strength, degree of polymerization, polymer solubility measurements, and infrared spectroscopic analyses (FT-IR). The results show that the incorporation of 1,3-dimethyl-4,5-dihydroxyethylene urea into the structure of cellulose highly decreased the biodegradability of cellulose macromolecules. This was confirmed by the smaller morphological changes, lower decrease of breaking strength and lower polymer solubility determined for the modified cellulose. FT-IR spectra analysis also revealed that during the biodegradation period much greater structural damage was caused in the case of unmodified than of modified cellulose, and that the intensity of the bands at 1640 and 1548 belonging to the Amides I and II bonds resulting from the presence of protein produced by microbial growth.

Breaking strength and elasticity of synthetic absorbable suture materials incubated in phosphate-buffered saline solution, milk, and milk contaminated with Streptococcus agalactiae

To determine in vitro effects of PBSS, milk, and bacteria-contaminated milk (BCM; contaminated by Streptococcus agalactiae) on properties of 3 synthetic absorbable suture materials. 3 types of synthetic absorbable suture materials (poliglecaprone 25, polyglycolic acid, and polydioxanone). Suture materials were tested to determine breaking strength and elasticity before (day 0) and after incubation in 3 media (PBSS, milk, and BCM) for 7, 14, and 21 days. A loop of suture material was elongated at a rate of 60 mm/min until it reached the breaking point. Tensile properties were statistically analyzed among media and incubation times. Incubation in milk and BCM significantly decreased breaking strength and elasticity of poliglecaprone 25, compared with results for incubation in PBSS. Incubation in BCM significantly decreased tensile properties of polyglycolic acid suture, compared with results for incubation in PBSS and milk. After incubation for 21 days, tensile properties of polydioxanone did not differ significantly among the media but were significantly decreased from values on day 0. On the basis of this study, poliglecaprone 25 is an inappropriate suture material for use in teat surgery. Polyglycolic acid suture should be avoided in teats of cattle with mastitis. Of the suture materials tested, polydioxanone was best suited for use in teat surgery, as determined on the basis of material testing after incubation in milk, even when the milk was contaminated with bacteria.

The effects of solar radiation upon breaking strength and elongation of fishing nets

The effect of solar radiation upon netting twines maintained under ambient conditions was investigated. Netting twines examined during the study were polyamide (PA) continuous filaments. These included 40 untreated grey twines (controls), 40 that were coated with a coal tar film to reduce UV radiation penetration of the fibres (treated), and 40 untreated green coloured twines. The last acted as a secondary control group. All twines were exposed to 780 h of direct solar radiation after which each was examined for breaking strength and extensibility. Results indicated that exposure of netting twines to solar radiation decreased breaking strength over time ( P<0.05), with the rate of deterioration being three times higher for untreated twines. In addition, coal tar treatment reduced elongation for up to 5 weeks following exposure.

Degumming of Sisal Fibres

The purpose of the study was to explore the effects of degumming using sodium hydroxide (NaOH) in softening sisal fibres for prospects in textile production. Based on reviewed literature on chemical degumming, it was hypothesized that an increase in NaOH concentration in the treatment solution will result in fibres with decreased breaking strength, linear density, stiffness and increased apparent elongation. A completely randomized experimental research design was used in this study, starting with a set of preliminary tests to determine the concentrations used in the actual experiment. Results revealed that with increased alkali concentration the breaking strength, linear density, stiffness, and apparent elongation were decreased. The optimal concentration of NaOH for degumming sisal was identified at 0.125N. At the optimal level, the breaking strength and apparent elongation were significantly decreased. Linear density of fibres and fibre stiffness were also decreased but not significantly. There was more fibre release from the binding materials at the optimal concentration, and the stain colour of the fibres was closer to cotton indicating more cellulose content. Sisal fibres were successfully degummed and foftened using NaOH. The results suggest that sisal could be explored in producing other textile products, such as bags, hats and rugs. 1 Food Science Department, Faculty of Agriculture, University of Swaziland, P/B Luyengo, Luyengo, Swaziland

The effects of chronic ketorolac tromethamine (toradol) on wound healing.

Intramuscular ketorolac is a commonly used nonsteroidal anti-inflammatory (NSAI) agent for analgesia in surgical patients. Increasing numbers of surgical patients are chronically taking some form of an NSAI drug. We examined the effects of "chronic" intramuscular ketorolac on the healing of a closed linear surgical wound in the rat. Wistar rats were pretreated with 4 mg per kilogram per day ketorolac intramuscularly prior to receiving dorsal incisional wounds. The ketorolac treatment was continued and after 2 weeks the wounds were excised and separated with a tensiometer to measure mechanical properties. Breaking strength was directly measured, tensile strength was calculated, and collagen concentrations at the wound site were determined. A significant decrease in the mean breaking strength was seen in the ketorolac-treated animals when compared to controls. The ketorolac-treated animals had a mean tensile strength less than the controls, although this difference did not reach statistical significance. The mean collagen concentration of the ketorolac-treated wounds was significantly less than the untreated wounds. Use of ketorolac for just 1 week prior to surgery in rats produced a significant decrease in the breaking strength of their wounds. With the increasing use of ketorolac in surgical patients as well as the increasing use of oral NSAI drugs, more study of this effect is warranted.