Postmortem Evaluation of Rabbit Carcasses Using Insect Populations in Keffi Nasarawa State, Nigeria

Untimely, forceful, and unexpected death is inevitable and common worldwide. Evidence for causes of death may be obtained through the knowledge of insects’ successional pattern and postmortem interval on dead carcasses. Two rabbits (Lepus cuniculus) weighing 2.5 kg each were used as the experimental animals. The rabbits were sacrificed by poisoning and stabbing, postmortem evaluation was achieved by taking record of the insect’s successional pattern. The insects’ successional pattern revealed the following insects’ species in order in which they arrived on the carcasses: Musca domestica, Lucilia sericata, Chrysomya albiceps, Dermestes maculatus, and Armadillidium vulgare (usual sp). The family Formicidae were represented by two unidentified species. M. domestica arrived first on the stabbed carcass while L. sericata on poisoned carcass. A total of 105±50 insects were collected throughout the study period, with stabbed rabbit contributing 61±10 and poisoned 44±60 insects’ species. Variation in the number of forensically important insects’ species encountered in the study site did not show any significant difference (p>0.05) in relation to each decomposition stage. There was however a significant difference (p<0.05) between insects’ relative abundance and mode of killing. Insect evidence was found 3 minutes after death on the stabbed carcass and 3 days after on the poisoned carcass. The study has shown that insects' population can be used to establish postmortem evidence in rabbit carcasses.

Thermogravimetric Analysis and Kinetic Study on Catalytic Pyrolysis of Rice Husk Pellet using Its Ash as a Low-cost In-situ Catalyst

The thermogravimetric behaviors and the kinetic parameters of uncatalyzed and catalyzed pyrolysis processes of a mixture of powdered raw rice husk (RRH) and its ash (RHA) in the form of pellets were determined by thermogravimetric analysis at three different heating rates, i.e., 5, 10, and 20 K/min, from 303 to 873 K. This research aimed to prove that the rice husk ash has a catalytic effect on rice husk pyrolysis. To investigate the catalytic effect of RHA, rice husk pellets (RHP) with the weight ratio of RRH:ARH of 10:2 were used as the sample. Model-free methods, namely Friedman (FR), Kissinger-Akahira-Sunose (KAS), and Flynn-Wall-Ozawa (FWO), were used to calculate the apparent energy of activation ( ). The thermogravimetric analysis showed that the decomposition of RHP in a nitrogen atmosphere could be divided into three stages: drying stage (303-443 K), the rapid decomposition stage (443-703 K), and the slow decomposition stage (703-873 K). The weight loss percentages of each stage for both uncatalyzed and catalyzed pyrolysis of RHP were 2.4-5.7%, 35.5-59.4%, and 2.9-12.2%, respectively. Using the FR, FWO, and KAS methods, the values of for the degrees of conversion (a) of 0.1 to 0.65 were in the range of 168-256 kJ/mol for the uncatalyzed pyrolysis and 97-204 kJ/mol for the catalyzed one. We found that the catalyzed pyrolysis led the to have values lower than those got by the uncatalyzed one. This phenomenon might prove that RHA has a catalytic effect on RHP pyrolysis by lowering the energy of activation.

Perubahan Kadar Nitrogen Total Pada Tanah Sebagai Alternatif Estimasi Post-Mortem Interval

Forensic taphonomy is a branch of forensic science which in its application uses processes related to the decomposition of corpses and uses soil evidence to estimate post-mortem interval (PMI) or post burial. Soil has evidential value because it contains minerals, plants and animal materials that are useful for characterization. This research was conducted by analyzing soil characteristics, namely soil pH and soil moisture and total nitrogen content in soil samples taken from under rabbit carcasses that were placed on the soil surface, buried 25 cm and 50 cm at each decomposition stage. The results obtained showed significant differences at each stage of decomposition and laying of the carcasses.

Volume of woody detritus in fresh maple-linden dibrova in Slobozhanskyi National Nature Park

The article examines the volume of coarse woody detritus in fresh maple-linden-dibrova in Slobozhanskyi National Nature Park. The study was carried out in 115-year-old forest with a predominance of common oak (Quercus robur L.) of natural origin on a sample plot (0.24 ha) by identifying and measuring of standing and lying dead wood components. The volume of dead wood in the forest ecosystem is 32.4 m3·ha–1 and consists of fallen (84.3%) and standing (15.7%). The main part of the dead wood volume is formed by one tree species — common oak (91.3%). In general, woody detritus is characterized by I–IV stages of decomposition, at the same time detritus of III (52.5%) and II (41.7%) stages prevails, detritus of other decomposition stages has insignificant shares (not exceeding 5.0%). No detritus of the last (V) stage of decomposition was detected. The volume of standing dead wood was 5.1 m3·ha–1 and is formed by whole and broken dead trees. In terms of species composition, common oak predominates (80.4%), other species have much smaller shares: small-leaved linden (Tilia cordata Mill.) (13.7%) and Norway maple (Acer platanoides L.) (5.9%). The volume of standing dead wood is dominated by detritus of decomposition stage II (4.8 m3·ha–1, 94.1%), compared with stage I (0.3 m3·ha–1, 5.9%). The volume of lying dead wood is 27.3 m3·ha–1 and is formed by whole fallen trees, fragments of fallen trees (trunks) and thick branches. In terms of species composition dead wood volume is dominated by common oak detritus (25.6 m3·ha–1, 93.7%), and the shares of other species are insignificant. Fallen dead wood is represented by four stages of decomposition (I–IV). In terms of volume, decomposition stage III has an absolute advantage (16.9 m3·ha–1, 61.9%), much less detritus of stage II (8.7 m3·ha–1, 31.9%). Relatively low volume of woody detritus and the absence of dead wood of decomposition stage V may be associated with forestry activities, including selective sanitary cutting and fallen woody debris removal, in the past in modern NNP areas.

Experimental Formation of Marine Abrasion on Bone and the Forensic Postmortem Submergence Interval

Human skeletal remains are frequently recovered from marine environments, where they have undergone months or years of immersion, and decomposition stage is no longer a possible method from which to estimate the postmortem submergence interval (PMSI). Over these longer PMSIs, a common taphonomic alteration that forms is the wearing and rounding of surfaces from marine abrasion, caused by repeated agitation in sediment or against rocks. Little is known about the timing of these changes and how to measure or score the degree of alteration. In a laboratory setting, multiple dry, defleshed bones of white-tailed deer (Odocoileus virginianus) were agitated in saltwater for varying intervals with abrasive sediment (1, 2, 4, 6, 8, and 10 days) and with rocks (5 and 12 days) using a laboratory tumbling device. These were compared to human remains cases from the Office of the Chief Medical Examiner, Boston, MA that had been in the Atlantic Ocean for known intervals. A five-stage (0–4) marine abrasion scoring system was devised for the taphonomic analysis of forensic cases from marine environments to allow for direct comparison among cases. A high degree of correlation between abrasion stage and known PMSI was detected.

Olfactory Choice for Decomposition Stage in the Burying Beetle Nicrophorus vespilloides: Preference or Aversion?

Sensory cues predicting resource quality are drivers of key animal behaviors such as preference or aversion. Despite the abundance of behavioral choice studies across the animal kingdom, relatively few studies have tested whether these decisions are driven by preference for one choice or aversion to another. In the burying beetle Nicrophorus vespilloides, adult pairs exhibit parental care to raise their offspring on a small carrion resource. We tested whether carrion decomposition stage affected brood quantity and quality and found that mating pairs had significantly more offspring on fresher carcasses. To determine whether this observed reproductive benefit correlates with maternal preference behavior, we conducted a series of olfactory trials testing mated female preferences for mouse carcasses of differing decomposition stages. When given the option between fresh and older carcasses, females associated significantly more with fresher, 1-day old carcasses. However, this behavior may be driven by aversion, as females that were given a choice between the 7-day old carcass and a blank control spent significantly more time in the control chamber. We characterized volatile organic compound profiles of both carcass types, highlighting unique compounds that may serve as public information (sensu lato) conveying resource quality information to gravid beetles.

An image super-resolution method for better cognition of images in cognition computing system

Data cognition plays an important role in cognitive computing. Cognition of low-resolution (LR) image is a long-stand problem because LR images have insufficient information about objects. For better cognition of LR images, a multi-resolution residual network (MRRN) is proposed to improve image resolution in this paper for cognitive computing systems. In MRRN, a multi-resolution feature learning (MRFL) strategy is introduced to achieve satisfying performance with low computational costs. Inspired by image pyramids, a feature pyramid is designed to implement multi-resolution feature learning in the building unit of the proposed MRRN. Specifically, multi-resolution residual units (MRRUs) are introduced as the building units of the proposed network, which consist of a feature pyramid decomposition stage and a feature reconstruction stage. To obtain informative features, transferred skip links (TSLs) are utilized to transfer fine-grain residual features in the pyramid decomposition stage to the reconstruction stage. The effectiveness of MRFL and TSL is demonstrated by ablation experiments. Also, the tests on standard benchmarks indicate the superiority of the proposed MRRN over other state-of-the-art methods.