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Biomechanical investigation is a multidisciplinary branch which joins biological-science and the mechanical engineering in order to understand the behaviour of organic materials. A finite element examination is comprehensively used to depict the mechanical conduct of the bones. Femur bone is perhaps the strongest and longest bone in the entire human body that is situated in thigh region and furthermore it is most prone to break during mishaps because of static loads or impact loads. In the current examination the finite element model is created by utilizing MRI information and modelling software to analyse the location of maximum stress in bone for different conditions using finite element analysing software to select the alternative composite material for Human Femur bone.

The objective of this research article is to perform the detailed study of femur bone by using finite element analysis method on ANSYS software. For this purpose literature review studied from 1980 to 2019. In previous studies the researcher did modal and structural analysis of femur bone at different boundary conditions. In this research modelling of femur bone was done on solid works taking the drawing dimensions of CT scanned femur bone and this model of femur bone was also scaled to 90% to 110% to because of anthropometrics. Natural frequencies of different size femur bone studied at different boundary conditions. Structural analysis has been performed and mode shapes at different natural frequencies studied. In this project the fracture has been identified and for healing the support plate and screws designed and fixed to fractured bone. Further structural and modal analysis done for varying the support plate material and strength analysis was performed. In order to enhance better healing and reducing loss in bone mineral density some improved materials has been found for surgical implants give scope for future study.

Effects of rearing cage type and dietary limestone particle size (LPS) on growth, apparent retention (AR) of nutrients, and bone quality were investigated. The treatments were arranged in a 2 × 3 factorial with cage (conventional, CON and furnished, FUR) and LPS (fine, < 0.595 mm, F; medium, 0.595 to < 1.68 mm, M; and 1:1 mixture of F and M wt/wt; FM). A total of 900-day-old Lohmann LSL-Lite chicks were placed in CON (20 chicks/cage) and FUR (30 chicks/cage) based on BW. The diets were formulated according to breeder's nutrient specifications for starter, grower, and developer phases. At the end of 4, 12, and 16 wk of age (woa), 2 pullets/cage were euthanized for samples. At 12 and 16 woa, 1 pullet/cage was transferred to metabolism cages for AR measurements. There was no interaction (P > 0.05) between cage type and LPS on response variables. At 4 woa, body (P = 0.002) and bone (P < 0.05) weight was higher for CON than FUR pullets, but this was reversed (P

Previous work has identified an effect of hatch time on chick femur mineralization. This experiment assessed the impact of hatch time and a 24-h post-hatch unfed time period on chick bone mineralization and yolk mineral utilization. In early hatching chicks, yolk Mg, Zn, K, P, Fe, and Cu decreased by 40 to 50% over the 24-h post-hatch unfed time period, whereas yolk Ca and Na decreased by 25 to 40% (P = 0.026). Yolk Sr was intermediate, decreasing by 37%. Late hatching chicks which had been hatched for no more than 30 h had a higher femur bone ash percentage compared to early hatching chicks which had spent over a 30-hour sojourn unfed in the incubator (P = 0.013). These results indicate that removing chicks from the incubator within 30 h of their hatch is likely to benefit their femoral mineralization.

This study is based on the biomechanical analysis of femur bone using Finite Element technique. Real life activities are taken as boundary conditions and the weight of a person is considered as load for walking, standing and jumping. For biomechanical analysis, three-dimensional CAD model of human femur bone is modelled from MRI/CT Scan data using ITK-Snap software. Pre-processing and post-processing operations are done using HYPERWORKS whereas the solver is NASTRAN 10.0. Analysis is done using three materials- natural bone material, AZ31 (magnesium alloy), CP Ti (Commercially Pure Titanium Alloy). Comparative study shows that CP-Ti material generates minimum stresses for jumping, standing and walking, which are 5.69, 5.34 and 5.71 MPa respectively. And also minimum displacements for jumping, standing and walking are 0.146, 0.0583 and 0.0623 mm respectively. It is found that AZ31 is the best suited material for Bone implants and as its weight is approximately same as natural bone.

This research work explores the area of biomedical image processing. A CAD model of human femur structure has been developed from computerized tomographic image taken as input data, which is further modified and segmented to form an accurate CAD model of a human femur by varying the segmentation methods and parameters, multi component model of whole femur structure is obtained as an assembly of bone. The segmentation is performed using an open source code ITK SNAP. This segmented CAD model of human femur structure can be used for engineering analysis such as static structural analysis, Model analysis and also used in manufacturing of handicapped aids, artificial bones, safety in sports equipment, design and implementing the rapid prototyping for Multi scaled model development.

Femur bone is the longest and strongest bone in the human body which is also known as thigh bone. The femur is responsible to bear the largest percentage of body weight during normal weight its length is 25% of the person’s total height. In this, a normal femur bone is reconstructed from DICOM files from CT scan using software 3D slicer and Blender. Meshing and Analysis are carried out in Ansys Workbench environment. Based on the weak zone areas that are obtained after a sudden a load is applied are taken as our zone of interest. Considering the zone of interest prosthetic plates and screws are modelled using Unigraphics NX 11.0 version and are assembled in the assembly module of the same software. In this, we constrain the bottom end of the femur bone

Bone are most important tissues, consists of raw materials like calcium and phosphorus. They develop rapidly during one of early years and make good themselves. The bone is particular as a linear-elastic, isotropic process and uniform material. Bones are an essential part of the human skeleton. It helps to maintain the softer parts of the body. Trauma is a chief cause of death and disability in both developed and increasing countries. The humanity physical condition association predicts that by the year 2021, trauma will be the leading origin of years of life lost for both urban and increasing nations. Bone crack is one of the common traumas. One method of curing the cracked bone is by joining the cracked bone by using bone joints. The main objective of this study is to compare bone joints are made up of dissimilar biomaterials aluminium alloy Al8090 series due to light weight with high strength and silicon carbide to improve the strength and find out the best material. Femur bone is modelled in SOLIDWORKS and analyzed using ANSYS 13.0. The crack fixation joints are also modelled and fractured bone and analyzed.

Vibration analysis is important for the evaluation of Natural frequencies and their effect on the bone for supportive equipment used while walking, running conditions. A femur bone is longest and taking the maximum load while standing, walking and running conditions. In present experimental research two types of conditions are used to evaluate natural frequencies of dead bone. While carried out experiment, FFT analyzer is used which gives desirable results of Natural frequencies. For analytical analysis, consistent mass matrices are used and natural frequencies are compared between analytical method and FFT analyzer. Average difference error between the two readings by consistent mass matrices and FFT analyzer is found to be less than one in first mode.

The stability on the fracture site is an important precondition for successful healing. Osteosynthesis is an alternative treatment for the stabilization of femur bone. Besides, the fractured bone experiences direct (primary) or indirect (secondary) healing which can be divided into two healing conditions (i.e. contact healing and gap healing). The healing of unstable fracture is essentially characterized by callus formation prior to healing. Understanding the stability on the fracture site is necessary to determine the parameters which will influence the implant stability. Nonetheless, there is a lack of study with regards to the influence of the osteosynthesis on the fixation strength and micro motion at of the fracture gap. Hence, for all intents and purposes, this study is aimed to investigate the influence of healing condition on the critical stress of cortex screws. Apart from that, this study is also expected to identify the yield region on cortex screws. Uninterruptedly, the results have revealed that the stress of plate fixation is significantly affected by the healing conditions. In particular, bone healing leads to a greater stress concentration on the screws, whilst the distribution is more uniform in contact healing condition. Furthermore, the results show that the different material properties at different modulus of bone healing imparted effect to the stress concentration on the screws.

Objective The present study aims to assess the correlation between stature and partial femur measurements in Japanese population, using three-dimensional (3D) computed tomographic (CT) images. Method A total of 195 cadavers (105 males, 90 females) underwent postmortem CT scanning and subsequent forensic autopsy between April 2013 and June 2014. Five femur length measurements were taken from 3D CT volume rendering (VR) images according to three anatomical landmarks: the greater trochanter, the lesser trochanter, and the adductor tubercle. The correlations between stature and each of the femur length measurements were assessed with Spearman's rank correlation test, and showed significant correlations between stature and femur length measurements. Results Using a mixed-sex regression formula, the R 2 was from 0.644 to 0.766 and actual difference was less than 4.6cm. Conclusion Present study showed that femur length measurements, according to the anatomical landmarks obtained from 3DCT VR images, were useful for estimation of the stature, particularly in cases when a total femur bone was not available.

We report a case of a Tunisian footballer who was found dead abroad under suspicious circumstances. The cause of death was, originally, attributed to a lightning strike. The corpse was buried without/autopsy. Over thirty years later, the family requested the exhumation to verify the identity and the cause of death. The exhumation was performed in 2011. DNA profiling from teeth and femur bone samples confirmed the identity of the deceased. The dry bone study revealed defects in the skull and the pelvis evoking firearm injuries. Post-mortem CT with three-dimensional (3-D) reconstruction allowed to confirm the characteristics of firearms injuries and to speculate about the number and the trajectories of potential shots. Nevertheless, the vitality of these injuries as well as the eventual fatal shot and the shooting distance could not be determined. Likewise, the type of the eventual weapon could not be clarified as there were no bullets or any metallic projectile fragments. Despite all doubts, the forensic explorations have allowed to verify the identity of the deceased, to evoke firearms injuries and, mainly, to deny the proposed cause of death after more than thirty years of burial. Moreover, the loss of soft tissues and bone fragility were the major obstacles.

Providing captive foxes with relevant enrichment objects may support their ability to cope with barren housing systems and thus have positive welfare effects. The relevance of enrichment objects is, among others, related to animals’ preference that should be examined prior to supplementing their housing environment. In this study, we assessed 30 juvenile, singly housed silver foxes’ short-term preference for five different oral enrichment objects based on their immediate use of the objects when they were given simultaneous access after one week of deprivation. Also, wear and tear after one week of continuous access was assessed as a measure of use and to estimate the robustness and durability of various objects. A cattle femur bone was clearly the first ranked object (P ≤ 0.05), followed by a rawhide bone, a mutual pulling device mounted between neighbouring cages, and straw and a plastic cube as the least used objects. All of the objects were, to a various degree, gnawed by the foxes. After one week of use, about 30% of the cattle bone mass was consumed, compared to about 88% of the rawhide bone mass. Although the plastic cubes were almost indestructible and therefore durable objects their low ranking do not necessarily make them good enrichment objects for foxes. Offering meat bones to captive foxes provide the animals with biologically relevant stimuli that elicit oral manipulation and play, behaviours with potential rewarding effects to the animals.

Objective The aim of present study is to evaluate the effect of Saraca indica extract for the management of dexamethasone-induced osteoporosis in rats. Methods Female Wister rats were used for the investigation of antiosteoporotic activity of S. indica extract at the dose of 200 mg/kg/day, orally and various parameters such as alkaline phosphatase estimation, bone density, bone biomechanical strength, and ash value of bone were determined in dexamethasone-induced osteoporosis. Results Alkaline phosphatase level in the blood serum and ash value of the bone was found to be significant (p

In this work the bone tissue remodelling analysis of the femur bone due to the insertion of a stem is analysed. The innovation of this numerical application lies on the use of an efficient advanced discretization meshless technique to obtain the variable fields required by the remodelling process.The remodelling algorithm used in this work allows to update locally and gradually the bone tissue density of the model. Based on the minimization of the strain energy density (SED), the remodelling algorithm uses a phenomenological bone tissue mathematical law, which permits to correlate the bone apparent density with its own mechanical properties. Comparing with other numerical approaches, the advanced discretization meshless technique used in this work allows to obtain smoother and more accurate SED fields, leading to more reliable remodelling predictions.The numerical remodelling results obtained for the femoral diaphysis after the insertion of the stem are in accordance with the clinical observation and with other numerical approaches results available in the literature.

Manganese in animal organisms is responsible for proper bone formation and many biochemical processes. The aim of the study was to determine the effect of manganese oxide nanoparticles (NanoMn2O3) as a mineral additive to the feed mixture on the growth, slaughter characteristics, femur bone strength, mineral content of tissues and Mn excretion. The male chickens were randomly divided between a control group without Mn2O3 in a premix, three groups receiving NanoMn2O3 (nano group 30, 60 and 100 % of the standard level) and three groups receiving Mn2O3 (30, 60 and 100 % of the standard level). Each group consisted of seven birds. The highest feed intake and body weight at 42 day was in the 60 % nano group, but there were no differences in the feed conversion rate. Slaughter characteristics, physicochemical properties, bone morphometry, the content of Mn in tissues and health status evaluated by blood parameters were not affected by supplying different forms of Mn2O3. Furthermore, the excretion of Mn was lower in NanoMn2O3 than in Mn2O3 groups. The results indicate that the application of NanoMn2O3 had no negative effects on chicken growth and development, but reduces Mn excretion, suggesting that commercial Mn2O3 can be replaced by NanoMn2O3 in broiler diets. However, follow-up research at farm conditions is necessary to validate the results.

In drilling of bones, surface roughness can be used as an indication of bone cell damage induced by the machining process. In common workpieces, relationship between both feed rate and cutting speed on surface roughness to the workpiece is apparent. It is expected that such relation also exists when bone is the workpiece. On the other hand, there are various quantifications or parameters of surface roughness. So, it needs to be confirmed which parameter that can suit the surface roughness on bone machining results. This study intends to evaluate the effect of cutting speed and feed rate on surface roughness of drilled bone, as well as to identify which surface roughness parameter fits for such machined surface. A series of experimental bone drilling was done by using two input variables (i.e., cutting speed and feed rate). The cutting speeds are 6 m/min and 37 m/min and the feed rates are 0.01 mm/rev and 0.2 mm/rev. For each machined surface, surface roughness was taken in five parameters (i.e., Ra, Rq, Rk, Rpk, and Rvk). The results show that feed rate significantly affects the surface roughness while cutting speed does not. Although further detail needs to be observed, it is confirmed that Ra parameter can be used in the measurement of surface roughness of bone machining results.

Biomechanical analysis is an interdisciplinary branch which combines biology and mechanical engineering to understand the behaviour of biological materials. Finite element analysis is widely used to describe the mechanical behaviour of bones. In this study a three dimensional virtual femur bone is modelled using Solid Edge V19 and the bone is analysed for hip contact stresses/forces during normal walking, standing, running and jumping activities. The stress analyses were carried out using ANSYS 14.0, a Finite Element code, in order to investigate the behaviour of the femur bone during these activities. The stress results obtained are compared with the previous studies and were found to be optimized.

This study related pharmaceutical formulation techniques with correction of retarded linear growth arising from poor nutritional status through a preclinical study. In our previous work, we formulated micronutrients supplementation as a sprinkle powder dosage form. Results of the physicopharmaceutical tests (i.e., uniformity of weight, angle of repose, tapped and bulk density, Hausner’s ratio, and Carr’s index) were acceptable values. Results obtained in this study showed that the best selected supplement formula (F5) was stable physically and chemically during storage period (40 °C and 75% RH) for 12 weeks. The in vivo study, carried out using 40 albino rats for 8 weeks, revealed that (F5) increased the weight and length of femur bone of severely malnourished rats by 16.6% ( p p p p

The main objective of the femur bone analysis is to know the natural frequencies, natural vibration modes and identify the fracture location of the bone through the computer simulation based on the FEA. Finite element Method or Finite Element Analysis is an approximation techniques used for the analysis of complex objects and geometries. The femur bone analysis is subjected to free- free and fixed-fixed boundary conditions. For these two different boundary conditions natural frequencies and natural vibration modes are identified. The mode shape shows that the natural frequency of free-free boundary condition varies from 0 Hz to 1381.1 Hz and for fixed-fixed boundary condition 1211 Hz to 7856.4 Hz. On the bases of these two boundary conditions mode shape is determined and fracture location can be easily notified. To prevent the fracture of femur bone external excitation frequency must be avoided to coincide with these natural frequencies. The results were compared with experimental results available in literature. For the design of femur bone model Solid Edge software is used and the model is imported in ANSYS R 14.5 (FEA based software) for the free vibration analysis.

Objectives We compared salivary flow, serum and saliva testosterone, and femur bone mineral density (BMD) of menopausal women with or without xerostomia. Study Design A case/control study was performed on 60 selected menopausal women with or without xerostomia. BMD and testosterone concentration were measured by a dual-energy x-ray absorptiometry system and enzyme-linked immunosorbent assay method, respectively. Results Multinomial logistic regression demonstrated that low saliva flow rate (odds ratio [OR] = 22.8, 95% confidence interval [CI]: 5.4, 96.8), low femur BMD (OR = 6.0, CI: 1.8, 20.0), high stimulated saliva testosterone (OR = 5.2, CI: 2.0, 18.9), high unstimulated saliva testosterone (OR = 3.8, 95% CI: 1.6, 12.3), and high serum testosterone (OR = 2.7, CI: 1.1, 7.2) were associated with an increased risk of xerostomia in menopausal women. Conclusions High serum and salivary testosterone and low femur BMD and saliva flow were associated with xerostomia. Of these factors, low salivary flow seems to be the most important element in the perception of dry mouth.

The mechanical properties and microstructure of young and mature bovine femur bone were investigated by optical microscopy and compression testing in the longitudinal and transverse directions for untreated, deproteinized and demineralized cases. Optical microscopy revealed that mature bone has a more established and less porous microstructure compared to young bone. Mature bone was found to be stronger in both directions for the untreated and deproteinized cases. Mature untreated bone was also found to be stiffer and less tough compared to young bone in both directions. These results are related to the increase in mineralization of mature bone and significant microstructural differences. Young bone was found to be stronger in both directions for the demineralized case, which is attributed to alterations in the collagen network with age.

Bones are living tissues, consists of minerals like calcium and phosphorus. They grow rapidly during one's early years and renew themselves. The bone is considered as a linear-elastic, isotropic and homogeneous material. Bones are the essential part of the human skeleton. It helps to support the softer parts of the body. Trauma is a major cause of death and disability in both developed and developing countries. The World Health Organization (WHO) predicts that by the year 2020, trauma will be the leading cause of years of life lost for both developed and developing nations. Bone fracture is one of the common trauma. One method of curing the fractured bone is by joining the fractured bone by using bone plates. The objective of this study is to compare bone plates made of different biomaterials (Stainless Steel, Titanium, Alumina, Nylon and PMMA) and find out the best material. Femur bone is modelled in SOLIDWORKS and analyzed using ANSYS. The fracture fixation plates are also modelled and fixed to a fracture bone and analyzed.

In this work the natural neighbour radial point interpolation method (NNRPIM), an improved meshless method, is extended to the bone remodelling analysis. A biomechanical model for predicting the bone density distribution was developed. The proposed gradient remodelling algorithm considers an anisotropic material law for the mechanical behaviour of the bone tissue, based on experimental data available in the literature, allowing to gradually correlate the bone density with the obtained level of stress. The viability and efficiency of the model were successfully tested on the classical femur bone example and a novel calcaneus bone example under multiple loading conditions.

The aim of current study was to elucidate whether aquaporin-9 (AQP9) expression was involved in the progression of bone loss induced by microgravity. We used the hind-limb suspension (HLS) mice model to simulate microgravity and induce bone loss. It was found that HLS exposure decreased femur bone mineral density (BMD), and enhanced femur AQP9 mRNA and protein levels. Then, the relationship between AQP9 mRNA expression and BMD was studied and it was showed that femur AQP9 mRNA level was negatively related to femur BMD in mice exposed to HLS. We sought to exam the function of AQP9 in the femur using the AQP9-null mice. It was found that AQP9 knockout attenuated bone loss and inhibited osteoclastogenesis under the condition of HLS exposure, but had no similar effect on bone under normal physiological conditions. In addition, it was found that exposure to simulated hypergravity or exercise training, main countermeasures against microgravity, reduced AQP9 mRNA and protein levels in femur of mice. Moreover, it was found that both aging and estrogen deprivation, another two risk factors of bone loss, had no significant effect on femur AQP9 expression. In conclusion, AQP9 plays an important role in the development of microgravity-induced bone loss, and may be a potential target for the prevention or management of microgravity-induced bone loss.

Wildlife has been utilized by humans throughout history and demand continues to grow today. Farming of wildlife can supplement the supply of wild-harvested wildlife products and, in theory, can reduce pressure on free-ranging populations. However, poached wildlife products frequently enter legal markets where they are fraudulently sold as farmed wildlife products. To effectively close this illegal trade in wild-captured wildlife, there is a need to discriminate wild products from farmed products. Because of the strong market demand for wild-captured frog meat and the resulting strong downward pressure on wild populations, we undertook research to develop a method to discriminate wild from farmed Dybowski's frog (Rana dybowskii) based on femur bone density. We measured femur bone density (D(f)) as the ratio of bone mass to bone volume. D(f) of wild frogs revealed a slightly increasing linear trend with increasing age (R(2)=0.214 in males and R(2)=0.111 in females, p=0.000). Wild males and wild females of age classes from 2 to ≥ 5 years had similar D(f) values. In contrast, 2-year-old farmed frogs showed significantly higher D(f) values (p=0.000) among males (mean D(f)=0.623 ± 0.011 g/ml, n=32) than females (mean D(f)=0.558 ± 0.011 g/ml, n=27). For both sexes, D(f) of wild frogs was significantly higher than that of farmed frogs (p=0.000). Among males, 87.5% (28 of 32 individuals) of farmed frogs were correctly identified as farmed frogs and 86.3% (69 of 80 individuals) of wild frogs were correctly identified as wild frogs. These results suggest that femur bone density is one reliable tool for discriminating between wild and farmed Dybowski's frog. This study also highlights a novel strategy with explicit forensic potential to discriminate wild from captive bred wildlife species.

Bone densitometry using fan-beam technology allows both femurs to be rapidly measured with the aid of a bilateral foot-positioning tool to keep both legs in internal rotation. The Lunar Prodigy® system uses a bilateral foot-positioning tool with a fixed interpedal width. The aim of this study was to determine whether the small degrees of femur abduction and adduction introduced by a fixed interpedal width-positioning tool influences the femur bone mineral density (BMD) measurements. Two-hundred patients had the total femur (FTot), femoral neck (FN), femoral shaft (FS), and femoral trochanter (FT) BMD, and angles of femoral abduction and adduction measured. Of all subjects, 26.5% had an absolute difference in femur angulation of #1°, 77.5% had #5° and 97% had #10°. There was no significant correlation between the right-to-left differences in femur angles and the absolute right-to-left differences in FTot, FN, FS, and FT BMD. The introduction of small degrees of femur angulation with the fixed interpedal width bilateral foot positioner does not significantly affect the measured BMD at the various femur regions.

Forty-seven hams were scanned four times by computed tomography (CT) while being manufactured into dry-cured hams. An image-processing algorithm measured CT values in the lean part of the hams and provided line profiles reflecting the magnitude and spatial location of salt gradients. At the end of manufacturing, seven entire hams were dissected and the salt content of the lean part determined. Likewise, in the remaining 40 hams, the lean meat of the slices corresponding to the CT images was dissected, analyzed chemically for NaCl and compared to the CT value. The salt content of entire dry-cured hams correlated well (r(2)=0.94) to the CT value of a 10 mm section located at the center of femur bone, perpendicular to the length axis of the hams. In the same position, significant correlations between the CT values before (r(2)=0.71) and after (r(2)=0.80) the ageing period and actual chemical analysis of the same section were demonstrated. Line profiles illustrating the combined salt distribution and dehydration within a ham related to the physical characteristics of the ham as well as to the manufacturing process. These findings reveal that the effects of altered manufacturing practices can be followed non-invasively, while hams are still in production. Computed tomography combined with appropriate image analysis offers advantages as a non-invasive tool in both research and product development.

Relationships between muscularity and muscle to bone ratio were investigated for beef carcasses of several breeds and crosses, and three genders using data from Bristol and Alberta. Side dissection data in terms of muscle, fat and bone weights were used to calculate muscle to bone ratios (MtoB) and muscularity indexes (MUSC) for the whole side or for the region around the femur bone. Highly significant breed and gender effects on MtoB and MUSC were shown for both the Bristol and the Alberta data sets, but the group differences for MtoB were not the same as those for MUSC despite the fact that these two characteristics were closely correlated. For both sets of data, for example, MUSC values at a common muscle plus bone weight were significantly higher for carcasses of bulls than heifers, but similarly adjusted MtoB values were generally higher for carcasses of heifers than bulls. Differences among breed groups were mainly in a similar direction for MUSC and MtoB, but the size of the differences varied widely. For example, relative to the Friesian, the Jersey breed had a significantly higher MtoB but a significantly lower MUSC, and carcasses of double-muscled bulls had a femur-region MtoB that was 19.2% greater than that of a group of Shorthorn-cross carcasses, but a MUSC that was only 1.7% higher. These findings show that because of the inconsistent relationships between muscularity and muscle to bone ratio among different classes of beef carcasses, lean meat yield cannot always be predicted without bias if measures of carcass shape are used as indicators of muscle to bone ratio.

Mexican diets are high in Phosphorus (P) with Ca/P ratios higher than recommended for optimum bone development. Beans and tortillas are the principal energy sources in the typical Mexican diet and these items are also the contributors of Calcium (Ca) and P. In the typical Mexican diet (vegetable diet of this study), beans contribute substantial quantities of Ca (129 mg/d) and P (266 mg/d) and 274 mg Ca/d and 200 mg P/d for corn tortillas. When milk is included (mixed diet), milk provides, 447 mg Ca/d and 350 mg P/d. The objective of this study was to investigate the effect of different Ca and P content typically found in Mexican diets on the growth and composition of rat femurs. Weanling rats were fed diets with different Ca and P content for 30 days, their femurs were extracted, weighed and the Ca and P content analyzed. Dietary Ca affects bone mass and Ca bone deposition (r=0.96;P

Bone samples of different archaeological sites and age have been employed to examine both the possible catalytic and immunological activity of Zn 2 Mg alkaline phosphatase. In six samples a protein of Mr 180±20 kD being closeto 200 kD of the contemporary enzyme was successfully isolated. The specific enzymic activity ranged from 5 to 100 mU/mg protein. In the presence of the inhibitors 1,10-phenanthroline and L-homoarginine the enzymic activity was diminished. Likewise heating to 100°C and replacement of Zn(II) by Cd(II) resulted in a dramatic loss of activity. Distinct immunological activity against the human enzyme was demonstrated in the Superdex 200 gel filtrate of one Anglo-Saxon femur bone (Bidwell, UK, ad 429–664) extract.

This paper is aimed at determining the number of screws and the dimensions of the appliance components of a hip nail-plate screw implant such that their sizes are a minimum (i.e. the implant weight is minimum), without the stresses in the appliance components as well as in the bone shaft exceeding the allowable limits. The implant-bone structure is idealized as a hybrid frame, composed of appliance components and the supporting femur bone elements, which act integrally to support the maximal load (during the gait cycle) at the hip joint. For various configurations of the implant, entailing different numbers of screws, the optimization technique is employed to determine the size of the members (nail, plate and screws) for a lightweight design. Implant configurations are analyzed for two, three, four and five nail configurations. The analysis of the hybrid (implant femur) frame, during each integrative object function and design parameter evaluation, is done by the Finite Element Method. The optimization problem is solved by the sequential unconstrained minimization technique (with the introduction of interior penalty function terms). It is found, from the results of analyses of the four hybrid frames, that the appliance frame, with two screws, yields the minimum-weight structurally safe design.

Precision and accuracy for rat whole body and excised femur bone mineral density (BMD) measurements were evaluated with two dual X-ray absorptiometry (DXA) systems. The 'small subject' mode on the Norland XR-26 (XR), and the 'ultra high resolution mode' on the Hologic QDR-1000/W(QDR) were used for the analysis. The whole body mode was only available on the XR. The lowest precision error for the whole body was found using a scan resolution of 1.0 x 1.0 mm and a scan speed of 15 mm/s. The scan spatial resolution of the femur measurement was approximately eight times higher on the QDR than on the XR. However, the XR allowed analysis of an arbitrary region of interest within the femur, which was not easily done with the QDR. Precision for the total femur measurement on the QDR (0.5-0.9%) was approximately two to four times superior to that of the XR (1.5-4.3%). The difference may be due to the superior scan resolution of the QDR. Bone mineral content and BMD on the QDR significantly declined with an increase of water depth (P0.001). No significant change was observed on the XR. Both DXA systems demonstrated an excellent correlation (ror = 0.98) with ash weight under the scan conditions examined. The optimal scan condition for the excised femur measurement on the XR was obtained with 1.5-2.5 cm of perspex or water and a scan speed of 10 mm/s. For the QDR, we recommend scanning the rat femur with approximately 2.5 cm of perspex or water in terms of precision and accuracy.

The application of the proton-induced X-ray emission method in combination with a proton microprobe (micro-PIXE) to studies of the mineralization process in selected organic matrices is presented. The flat-bone mineralization of the skull of 17–19 days pregnancy mouse embryos is described in detail. The section thickness as well as concentrations of P, S, Cl, K, Ca, Zn and Br were determined using the raster- or line-scan irradiation mode. On the basis of Ca and P contents the amount of inorganic phase was determined for each sample under investigation, while the Ca/P ratio was used for the identification of the chemical compounds within inorganic material. In the embryonal bones we observed almost stoichiometric hydroxyapatite; however, in the intramembranaceous ossification of the young (17 day) animals, octacalcium phosphate was identified. At the given age of the embryo the amount of minerals is much higher in the femur bone than in flat bone. The micro-PIXE method furthermore turned out to be sensitive enough to study the mineralization accompanying malignant tumors. We have also observed the involvement of some trace elements in the development of the mineralization process. The last two observations are unattainable by histological staining.

Characteristics of fat in bones from two different anatomical locations (rib bone tissue and femur bone marrow) in young and old buffalo, sheep, camel, pig, cow and goat, with a view to utilizing it either for human consumption or industrial purposes, are reported. The fat content of rib bone tissue and long bone marrow ranged from 3·6–11·4% and 84·5–96·9% (fresh weight) respectively. Triglycerides constituted the major class of fat in all cases. The predominant fatty acids were C 16:0 , C 18:0 and C 18:1 . Some differences in fats in relation to anatomy and species were evident.

The bioavailability of iron in Fephytate and Ca 3 Fephytate and of zinc in Zn 2 phytate and Ca 4 Zn 2 phytate was assayed in rats. Hemoglobin response was the same to the iron of Fephytate as the reference iron compound, Fe(NH 4 ) 2 (SO 4 ) 2 .6H 2 ) but the response to iron of Ca 3 Fephytate was significantly less than to both Fephytate and the reference. The zinc of Zn 2 phytate and Ca 4 Zn 2 phytate promoted growth as effectively as did ZnSO 4 . The femur bone zinc response to Ca 3 Zn 2 phytate and Zn 2 phytate did not differ significantly but the femur zinc responses to both complexes were significantly less than to ZnSO 4 . In contrast to iron, calcium in a preformed calcium-zinc-phytate complex appears to have no significant effect on the bioavailability to rats of the zinc in the complex.

The purpose of this study was to determine changes in the soft or hard tissue surrounding isolated intraosseous implants. Implant screws were machined to uniform dimension from three gold-base alloys, two cobalt-base alloys, two stainless steel, and one platinum-iridium alloy. Adult, male albino rats (375 to 475 grams) were used. Perforations were made on the lateral aspect of the femur bone by means of friction-grip, round carbide burs, and screws were placed loosely in the perforations. Each animal received one implant only. Sham-operated controls were included for each group. Animals were killed at intervals of 1, 2, 3, 4, and 5 weeks. Longitudinal sections of the bone (with respect to the longitudinal axis of the implant) were stained with hematoxylin and eosin. A layer of connective tissue was present surrounding all implants. This capsule differed according to the type of metal and the duration of implantation. The formation and maturation of new bone appeared to have begun in the spiral adjacent to the periosteal end of the screw and to have proceeded toward the apex of the screw. Implants were completely encapsulated by newly formed bone at the end of the fourth week. The rate of formation of bone appeared to be higher in the control wounds. On the basis of the amount of bone formed around the implants, cobalt-base and stainless steel alloys were found to be more suitable for implantation than the other materials tested.

INTRODUCTION THE literature contains considerable evidence, both direct and indirect, supporting the partial resorption of skeletan mineral during egg shell formation in the avian species. Cox and Balloun (1971) reviewed some of the related literature. Hurwitz and Bar (1969), have stated that, in their opinion, the function of bone in supplying calcium to the egg shell has been considerably overestimated. The evidence presented by Cox and Balloun (1970) and that presented by Taylor (1961), does not support this opinion. One possible explanation for this lack of agreement is the differences in the period of the hen’s reproductive cycle investigated. This report is an extension of our previous paper (Cox and Balloun, 1970) and contains the results from two experiments to study the utilization of femur bone mineral after onset of egg production in commercial strains of pullets. MATERIALS AND METHODS Physiological factors studied on individual birds were 140-day body weight,…