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1.
Age‐at‐death estimation of an individual skeleton is important to forensic and biological anthropologists for identification and demographic analysis, but it has been shown that the current aging methods are often unreliable because of skeletal variation and taphonomic factors. Multifactorial methods have been shown to produce better results when determining age‐at‐death than single indicator methods. However, multifactorial methods are difficult to apply to single or poorly preserved skeletons, and they rarely provide the investigator with information about the reliability of the estimate. The goal of this research is to examine the validity of the Sugeno fuzzy integral as a multifactorial method for modeling age‐at‐death of an individual skeleton. This approach is novel because it produces an informed decision of age‐at‐death utilizing multiple age indicators while also taking into consideration the accuracies of the methods and the condition of the bone being examined. Additionally, the Sugeno fuzzy integral does not require the use of a population and it qualitatively produces easily interpreted graphical results. Examples are presented applying three commonly used aging methods on a known‐age skeletal sample from the Terry Anatomical Collection. This method produces results that are more accurate and with smaller intervals than single indicator methods. Am J Phys Anthropol 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

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Currently in physical anthropology there is a need for reliable methods of sex estimation for immature individuals and highly fragmented remains. This study develops a sex estimation technique from discriminant function analysis of the bony labyrinth as it matures before puberty and can survive taphonomic conditions that would destroy most other skeletal material. The bony labyrinth contains the organs of hearing and balance. For this reason biologists and paleoanthropologists have undertaken research in this area to understand evolutionary changes in locomotion. Prior studies have found clear differences between species, but within‐species variation has not been satisfactorily investigated. 3D segmentations of the left and right labyrinths of 94 individuals from a Cretan collection were generated and measured. Mean measurements of height, width, size, and shape indices were analyzed for sexual dimorphism, bilateral asymmetry, and measurement error. Significant sexual dimorphism was detected for several measurements. For sex estimation, the single best variable was the radius of curvature of the posterior semicircular canal, which achieved 76% accuracy. Two multivariate functions increased accuracy to 84%. Although these equations are less accurate than equations for complete long bones and crania, they appear to be as accurate as or better than other techniques for sexing immature individuals and temporal bones. Am J Phys Anthropol 151:290–301, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

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The thermoregulation behavior of Lucilia sericata larvae (Diptera: Calliphoridae), a necrophagous species that feeds on vertebrate cadavers, was investigated. These larvae require high heat incomes to develop, and can elevate temperatures by forming large aggregates. We hypothesized that L. sericata larvae should continue to feed at temperatures up to 38 °C, which can be reached inside larval masses. Thermal regulation behavior such as movement between a hot food spot and colder areas was also postulated. The hypotheses were tested by tracking for 1 h the activity of single, starved third instar larvae in a Petri dish containing 1 food spot (FS) that was heated to a constant temperature of 25 °C, 34 °C or 38 °C with an ambient temperature of 25 °C. The influence of previous conspecific activity in the food on larval behavior was also tested. The crops of larvae were dissected to monitor food content in the digestive systems. Based on relative crop measurements, larvae fed at all food temperatures, but temperature strongly affected larval behavior and kinematics. The total time spent by larvae in FS and the duration of each stay decreased at high FS temperature. Previous activity of conspecifics in the food slightly increased the time spent by larvae in FS and also decreased the average distance to FS. Therefore, necrophagous L. sericata larvae likely thermoregulate during normal feeding activities by adjusting to local fluctuations in temperature, particularly inside maggot masses. By maintaining a steady internal body temperature, larvae likely reduce their development time.  相似文献   

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The influences of temperature and host species on the development of the forensically important parasitoid Tachinaephagus zealandicus Ashmead (Hymenoptera: Encyrtidae) were studied at six constant temperatures in the range of 15–30°C. T. zealandicus completed development successfully between 15°C and 27°C on five species of Calliphoridae, Calliphora albifrontalis Malloch, Calliphora dubia Macquart, Lucilia sericata Meigen, Chrysomya rufifacies Macquart and Chrysomya megacephala Fabricius. No adult parasitoids emerged from any of the host species reared at 30°C. Temperature and host species significantly influenced development time, emergence success and progeny size. Development was significantly longer on Ch. megacephala and Ch. rufifacies at 18–24°C and significantly longer on Ch. rufifacies and C. albifrontalis at 15°C and 27°C. Parasitoid emergence success was greatest at 21°C, declined at the temperature extremes (15°C and 27°C) and was significantly lower on Ch. megacephala and Ch. rufifacies than on the three other host species. Progeny numbers per host pupa were highest at 21–24°C, declined on either side of this temperature range and were significantly lower on L. sericata, Ch. rufifacies and Ch. megacephala than on either C. dubia or C. albifrontalis. An effect of host species on sex ratio was only observed at 27°C, at which a higher proportion of T. zealandicus females emerged from Ch. megacephala and Ch. rufifacies than from the other host species. The thermal requirements for development (developmental thresholds, thermal constant, optimum temperature) of T. zealandicus in each host species were estimated using linear and non‐linear models. Upper and lower developmental thresholds ranged between 29.90°C and 31.73°C, and 9.73°C and 10.08°C, respectively. The optimum temperature for development was estimated at between 25.81°C and 27.05°C. Given the significant effect of host species on development time, the use of parasitoid–host‐specific developmental data in forensic application is recommended.  相似文献   

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Almost half of all US households own a dog (Canis familiaris). Though these household pets can attack humans and other animals, they are also frequently victims of cruelty, neglect and theft. In human‐oriented investigations, the tendency of domestic dogs to leave behind physical traces (such as hair) can serve as valuable links between crime scenes and suspects/victims. This demonstrated utility of canine biological evidence has created demand for genotyping marker sets for canine forensic genetic testing. Through research and casework, short tandem repeat (STR) panels have been shown to be very efficient for identity and parentage testing in dogs. However, there is an absence of comparative studies between different canine forensic identification kits. The Thermo Fisher Scientific Canine Genotypes ? Panel 1.1 and 2.1 Kits were originally designed and developed for routine and forensic use respectively, although both kits can be used for either purpose. In this study, we evaluated both STR panels to determine how critical forensic genetic metrics are affected by panel‐to‐panel variation in marker composition and design. Our results show that although STR panel composition can influence estimates such as inbreeding, combined power of discrimination and combined probability of exclusion, greater average allele number values exhibited across all markers in Panel 2.1 facilitated significantly more precise estimates of random match probability (RMP) and combined probability of identity. Furthermore, we demonstrate that a theta (θ) correction of 0.09 can be used to conservatively adjust RMPs generated from a small reference database of fewer than 50 samples, confirming that Panel 2.1 is a more robust forensic genotyping system than is Panel 1.1. for domestic dogs. We also demonstrate that opportunistic local sampling of fewer than 50 mixed‐breed dogs can produce sufficient discriminatory and exclusionary power with either genotyping kit.  相似文献   

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The spheno‐occipital synchondrosis is a craniofacial growth centre between the occipital and sphenoid bones—its ossification persists into adolescence, which for the skeletal biologist, means it has potential application for estimating subadult age. Based on previous research the timing of spheno‐occipital fusion is widely variable between and within populations, with reports of complete fusion in individuals as young as 11 years of age and nonfusion in adults. The aim of this study is, therefore, to examine this structure in a mixed sex sample of Western Australian individuals that developmentally span late childhood to adulthood. The objective is to develop statistically quantified age estimation standards based on scoring the degree of spheno‐occipital fusion. The sample comprises multidetector computed tomography (MDCT) scans of 312 individuals (169 male; 143 female) between 5 and 25 years of age. Each MDCT scan is visualized in a standardized sagittal plane using three‐dimensional oblique multiplanar reformatting. Fusion status is scored according to a four‐stage system. Transition analysis is used to calculate age ranges for each defined stage and determine the mean age for transition between an unfused, fusing and fused status. The maximum likelihood estimates for the transition from open to fusing in the endocranial half is 14.44 years (male) and 11.42 years (female); transition from fusion in the ectocranial half to complete fusion is 16.16 years (male) and 13.62 years (female). This study affirms the potential value of assessing the degree of fusion in the spheno‐occipital synchondrosis as an indicator of skeletal age. Am J Phys Anthropol 153:132–138, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   

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Abstract 1. To overcome the challenge of host location in patchy and complex environments, many parasitoids exploit host‐habitat derived odour cues. This study investigated the role of odour cues used during host location by the generalist parasitoid, Tachinaephagus zealandicus, a common parasitoid of Dipteran larvae found in association with decomposing carrion. 2. A Y‐tube olfactometer was used to test aspects of host searching behaviour of T. zealandicus females under different choice scenarios: combinations of host–liver complex, eaten liver, unwashed host larvae, washed host larvae, liver in six stages of decay, and control (no odour). 3. T. zealandicus females demonstrated an innate response to, and preference for, odours arising from liver substrates following interaction with the host. However, this was dependent on the stage of meat decay. Females were not attracted to liver that had never been in contact with a host, regardless of the stage of decay. There were discernible differences in parasitoid movement and behaviour under different choice scenarios. The absence of odour stimulus elicited limited movement about the olfactometer. In the presence of any odour stimuli, females were more active within the olfactometer, and when presented with two odour options T. zealandicus females demonstrate a heightened investigation response, moving across all regions of the olfactometer. 4. Knowledge of the cues that mediate host location for T. zealandicus can contribute to fields such as forensic entomology, where the presence of parasitoids on decomposing remains can be used to estimate time since death.  相似文献   

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Due to disparity regarding the age at which skeletal maturation of the spheno‐occipital synchondrosis occurs in forensic and biological literature, this study provides recalibrated multislice computed tomography (MSCT) age standards for the Australian (Queensland) population, using a Bayesian statistical approach. The sample comprises retrospective cranial/cervical MSCT scans obtained from 448 males and 416 females aged birth to 20 years from the Skeletal Biology and Forensic Anthropology Research Osteological Database. Fusion status of the synchondrosis was scored using a modified six‐stage scoring tier on an MSCT platform, with negligible observer error (κ = 0.911 ± 0.04, intraclass correlation coefficient = 0.994). Bayesian transition analysis indicates that females are most likely to transition to complete fusion at 13.1 years and males at 15.6 years. Posterior densities were derived for each morphological stage, with complete fusion of the synchondrosis attained in all Queensland males over 16.3 years of age and females aged 13.8 years and older. The results demonstrate significant sexual dimorphism in synchondrosis fusion and are suggestive of intrapopulation variation between major geographic regions in Australia. This study contributes to the growing repository of contemporary anthropological standards calibrated for the Queensland milieu to improve the efficacy of the coronial process for medicolegal death investigation. As a stand‐alone age indicator, the basicranial synchondrosis may be consulted as an exclusion criterion when determining the age of majority that constitutes 17 years in Queensland forensic practice. Am J Phys Anthropol 157:42–57, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   

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1. Third instars of the invasive blow fly Chrysomya rufifacies are facultative predators on larvae of the native blow fly Cochliomyia macellaria. 2. The effects of priority arrival time on the survivorship and fitness of C. rufifacies and C. macellaria were investigated in laboratory experiments. 3. Cochliomyia macellaria colonising a resource within 1–2 days after C. rufifacies resulted in a 20–70% reduction in survivorship, pupal weight and fecundity compared with those colonising a resource more than 2 days before or after C. rufifacies. Inversely, C. rufifacies exhibited a 50% increase in survivorship and fecundity when closely (~2 days) associated temporally on the resource with C. macellaria and was negatively affected by disparate arrival. 4. These results demonstrate that arrival sequence significantly affects the fitness of both C. rufifacies and C. macellaria. Early colonisation may allow C. macellaria to persist in a community, while there are fitness benefits for C. rufifacies colonising after C. macellaria. 5. The 60% reduction in C. macellaria survivorship when in close temporal association with C. rufifacies may act as an agent of selection for C. macellaria to colonise a resource early and develop quickly to avoid predation on resources colonised by C. rufifacies. 6. Selection for such traits may explain how C. macellaria is able to persist despite intraguild predation by this invasive species. In contrast, the 50% increase in survivorship and fecundity exhibited by C. rufifacies when arriving after C. macellaria may select for C. rufifacies to delay colonisation.  相似文献   

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This study investigated whether infrared spectroscopy combined with a deep learning algorithm could be a useful tool for determining causes of death by analyzing pulmonary edema fluid from forensic autopsies. A newly designed convolutional neural network‐based deep learning framework, named DeepIR and eight popular machine learning algorithms, were used to construct classifiers. The prediction performances of these classifiers demonstrated that DeepIR outperformed the machine learning algorithms in establishing classifiers to determine the causes of death. Moreover, DeepIR was generally less dependent on preprocessing procedures than were the machine learning algorithms; it provided the validation accuracy with a narrow range from 0.9661 to 0.9856 and the test accuracy ranging from 0.8774 to 0.9167 on the raw pulmonary edema fluid spectral dataset and the nine preprocessing protocol‐based datasets in our study. In conclusion, this study demonstrates that the deep learning‐equipped Fourier transform infrared spectroscopy technique has the potential to be an effective aid for determining causes of death.  相似文献   

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Since the future of anthropology in Australia is clouded, the address takes a look at where it has been coming from. Rather than a distinctive regional school, the discipline in Australia has been part of anthropology in the UK and the USA. In common with anthropology elsewhere, it lacks a distinctive theoretical stance, but draws on the theory current in the other social sciences. Recognising that what makes anthropology ‘special’ is the field work experience, the address reflects on the history and nature of this practice.  相似文献   

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The acetylcholinesterase inhibition by enantiomers of exo‐ and endo‐2‐norbornyl‐Nn‐butylcarbamates shows high stereoselelectivity. For the acetylcholinesterase inhibitions by (R)‐(+)‐ and (S)‐(?)‐exo‐2‐norbornyl‐Nn‐butylcarbamates, the R‐enantiomer is more potent than the S‐enantiomer. But, for the acetylcholinesterase inhibitions by (R)‐(+)‐ and (S)‐(?)‐endo‐2‐norbornyl‐Nn‐butylcarbamates, the S‐enantiomer is more potent than the R‐enantiomer. Optically pure (R)‐(+)‐exo‐, (S)‐(?)‐exo‐, (R)‐(+)‐endo‐, and (S)‐(?)‐endo‐2‐norbornyl‐Nn‐butylcarbamates are synthesized from condensations of optically pure (R)‐(+)‐exo‐, (S)‐(?)‐exo‐, (R)‐(+)‐endo‐, and (S)‐(?)‐endo‐2‐norborneols with n‐butyl isocyanate, respectively. Optically pure norborneols are obtained from kinetic resolutions of their racemic esters by lipase catalysis in organic solvent. Chirality 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

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With the rising demand for flexible and wearable electronic devices, flexible power sources with high energy densities are required to provide a sustainable energy supply. Theoretically, rechargeable, flexible Li‐O2/air batteries can provide extremely high specific energy densities; however, the high costs, complex synthetic methods, and inferior mechanical properties of the available flexible cathodes severely limit their practical applications. Herein, inspired by the structure of human blood capillary tissue, this study demonstrates for the first time the in situ growth of interpenetrative hierarchical N‐doped carbon nanotubes on the surface of stainless‐steel mesh (N‐CNTs@SS) for the fabrication of a self‐supporting, flexible electrode with excellent physicochemical properties via a facile and scalable one‐step strategy. Benefitting from the synergistic effects of the high electronic conductivity and stable 3D interconnected conductive network structure, the Li‐O2 batteries obtained with the N‐CNTs@SS cathode exhibit superior electrochemical performance, including a high specific capacity (9299 mA h g?1 at 500 mA g?1), an excellent rate capability, and an exceptional cycle stability (up to 232 cycles). Furthermore, as‐fabricated flexible Li‐air batteries containing the as‐prepared flexible super‐hydrophobic cathode show excellent mechanical properties, stable electrochemical performance, and superior H2O resistibility, which enhance their potential to power flexible and wearable electronic devices.  相似文献   

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Epilepsy, one of the most frequent neurological disorders, is still insufficiently treated in about 30% of patients. As a consequence, identification of novel anticonvulsant agents is an important issue in medicinal chemistry. In the present article we report synthesis, physicochemical, and pharmacological evaluation of N‐trans‐cinnamoyl derivatives of R and S‐2‐aminopropan‐1‐ol, as well as R and S‐2‐aminobutan‐1‐ol. The structures were confirmed by spectroscopy and for derivatives of 2‐aminopropan‐1‐ols the configuration was evaluated by means of crystallography. The investigated compounds were tested in rodent models of seizures: maximal electroshock (MES) and subcutaneous pentetrazol test (scPTZ), and also in a rodent model of epileptogenesis: pilocarpine‐induced status prevention. Additionally, derivatives of 2‐aminopropan‐1‐ols were tested in benzodiazepine‐resistant electrographic status epilepticus rat model as well as in vitro for inhibition of isoenzymes of cytochrome P450. All of the tested compounds showed promising anticonvulsant activity in MES. For R(–)‐(2E)‐N‐(1‐hydroxypropan‐2‐yl)‐3‐phenylprop‐2‐enamide pharmacological parameters were found as follows: ED50 = 76.7 (68.2–81.3) mg/kg (MES, mice i.p., time = 0.5 h), ED50 = 127.2 (102.1–157.9) mg/kg (scPTZ, mice i.p., time = 0.25 h), TD50 = 208.3 (151.4–230.6) mg/kg (rotarod, mice i.p., time = 0.25 h). Evaluation in pilocarpine status prevention proved that all of the reported compounds reduced spontaneous seizure activity and act as antiepileptogenic agents. Both enantiomers of 2‐aminopropan‐1‐ols did not influence cytochrome P450 isoenzymes activity in vitro and are likely not to interact with CYP substrates in vivo. Chirality 28:482–488, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   

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Several new and differently functionalized cis‐2,3‐dimethylnorbornane derivatives presenting diverse side‐chain lengths were prepared, the structures of which are related to the natural fragrance β‐santalol. In particular, exo‐ and endo‐3,8‐dihydro‐β‐santalols, with either (E) or (Z) C?C‐bond configuration on the side chain, were synthesized in seven steps and 21–24% overall yields. Several other exo‐ and endo‐norbornyl alcohols with shorter side chains were also prepared in high yields. The olfactory evaluation indicated woody, sandalwood, as well as fruity notes for some of the derivatives.  相似文献   

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