Beyond Henssge's Formula: Using Regression Trees and a Support Vector Machine for Time of Death Estimation in Forensic Medicine.

Henssge's nomogram is a commonly used method to estimate the time of death. However, uncertainties arising from the graphical solution of the original mathematical formula affect the accuracy of the resulting time interval. Using existing machine learning techniques/tools such as support vector machines (SVMs) and decision trees, we present a more accurate and adaptive method for estimating the time of death compared to Henssge's nomogram. Using the Python programming language, we built a synthetic data-driven model in which the majority of the selected tools can estimate the time of death with low error rates even despite having only 3000 training cases. An SVM with a radial basis function (RBF) kernel and AdaBoost+SVR provided the best results in estimating the time of death with the lowest error with an estimated time of death accuracy of approximately ±20 min or ±9.6 min, respectively, depending on the SVM parameters. The error in the predicted time (tp[h]) was tp±0.7 h with a 94.45% confidence interval. Because training requires only a small quantity of data, our model can be easily customized to specific populations with varied anthropometric parameters or living in different climatic zones. The errors produced by the proposed method are a magnitude smaller than any previous result.

Disentangling the ecosystem service 'flood regulation': Mechanisms and relevant ecosystem condition characteristics.

Riverine floods cause increasingly severe damages to human settlements and infrastructure. Ecosystems have a natural capacity to decrease both severity and frequency of floods. Natural flood regulation processes along freshwaters can be attributed to two different mechanisms: flood prevention that takes place in the whole catchment and flood mitigation once the water has accumulated in the stream. These flood regulating mechanisms are not consistently recognized in major ecosystem service (ES) classifications. For a balanced landscape management, it is important to assess the ES flood regulation so that it can account for the different processes at the relevant sites. We reviewed literature, classified them according to these mechanisms, and analysed the influencing ecosystem characteristics. For prevention, vegetation biomass and forest extent were predominant, while for mitigation, the available space for water was decisive. We add some aspects on assessing flood regulation as ES, and suggest also to include flood hazard into calculations.

Sternal aspirate sampling of Bacillariophyceae (diatoms) and Cyanobacteria in suspected drowning cases.

A diagnosis of drowning is not always possible based on the traditional autopsy findings. The most widely used ancillary methods are based on the detection of diatoms and other waterborne organisms in the organs of the systemic circulation by light microscope or polymerase chain reaction (PCR). One of the greatest concerns is sample contamination. Bone marrow is a favourable source because the compact bone protects the sample from water ingress in the case of advanced decay. In our pilot study, we aimed to adopt sternal bone marrow aspiration - which is a widely used technique in haematology - for postmortem sampling. Control experiments of non-drowning victims showed that cleaning the skin over the sternum can prevent external contamination. Sternal aspirate samples were taken from seven suspected drowning victims along with lung, spleen, and femoral bone marrow samples. All specimens were examined for the presence of diatoms by light microscope and Cyanobacteria-specific DNA by PCR. We were able to obtain bone marrow aspirates from all cases without complications. In four of the sternal samples both diatoms and cyanobacterial DNA were detected, while one additional sternum sample was tested positive with PCR, but no diatom shells were detectable. Sternal bone marrow aspiration is simple and quick, which can be performed at the beginning of an autopsy, minimizing the chance of contamination. We have shown that this sampling method can be adopted for postmortem diatom testing. This minimally invasive technique might be used in virtual autopsy (postmortem computed tomography, PMCT) settings without opening body cavities.

Characterization of Kisspeptin Neurons in the Human Rostral Hypothalamus.

BACKGROUND: Kisspeptin (KP) neurons in the rostral periventricular region of the 3rd ventricle (RP3V) of female rodents mediate positive estrogen feedback to gonadotropin-releasing hormone neurons and, thus, play a fundamental role in the mid-cycle luteinizing hormone (LH) surge. The RP3V is sexually dimorphic, and male rodents with lower KP cell numbers are unable to mount estrogen-induced LH surges. OBJECTIVE: To find and characterize the homologous KP neurons in the human brain, we studied formalin-fixed post-mortem hypothalami. METHODS: Immunohistochemical techniques were used. RESULTS: The distribution of KP neurons in the rostral hypothalamus overlapped with distinct subdivisions of the paraventricular nucleus. The cell numbers decreased after menopause, indicating that estrogens positively regulate KP gene expression in the rostral hypothalamus in humans, similarly to several other species. Young adult women and men had similar cell numbers, as opposed to rodents reported to have more KP neurons in the RP3V of females. Human KP neurons differed from the homologous rodent cells as well, in that they were devoid of enkephalins, galanin and tyrosine hydroxylase. Further, they did not contain known KP neuron markers of the human infundibular nucleus, neurokinin B, substance P and cocaine- and amphetamine-regulated transcript, while they received afferent input from these KP neurons. CONCLUSIONS: The identification and positive estrogenic regulation of KP neurons in the human rostral hypothalamus challenge the long-held view that positive estrogen feedback may be restricted to the mediobasal part of the hypothalamus in primates and point to the need of further anatomical, molecular and functional studies of rostral hypothalamic KP neurons.

A spatially explicit analysis of wheat and maize yield sensitivity to changing groundwater levels in Hungary, 1961-2010.

Groundwater (GW) in many regions is essential for agricultural productivity, especially during drought periods. The shrinking of GW is an important but rarely documented component of the recent global environmental crisis and may threaten food security. The problem cannot be put in proper perspective, because we rarely have datasets long and detailed enough to scrutinise the unfolding effects at regional scales. To address this knowledge gap, we used a 50-y long (1961-2010) and spatially extensive (283 GW wells) dataset from Hungary to examine the GW trends and the sensitivity of the yields of two important crops to GW fluctuations. During 1986-2010, GW levels were significantly (0.21-0.60 m) lower than during 1961-1985 in every region of Hungary and every month of the year. The decrease was 2.24 cm y-1 at the country level. Linear and bootstrap resampling tests indicated weak relationship between GW levels and wheat yields but decreasing GW levels accounted for 18-38% of maize yield variability during the 'climate change affected' period of 1986-2010. Calculating the impact of GW on potential food production, a 100 mm higher GW levels would have increased annual maize yields by 0.23 t ha-1 on the Hungarian Plain. However, the registered GW decrease caused an estimated maize yield loss of 0.65 t ha-1, i.e. 11.6% of the average annual yield during 1986-2010. GW level fluctuations on the plain showed a significant correlation with August-October soil moisture gridded data over much of the agricultural landscapes of Central and Western Europe, indicating a similar situation in a wider European context. To mitigate the cumulative negative impact of GW decrease and the rising temperature, GW recharge via infiltration of retained water would be an adequate solution. Areas of former floodplains with low agroecological suitability, amounting to almost a quarter of the Hungarian Plain could serve as such water retention areas.

The effect of steatosis and fibrosis on blunt force vulnerability of the liver.

The aim of our study was to examine the possible effect of steatosis and fibrosis on the blunt force vulnerability of human liver tissue. 3.5 × 3.5 × 2-cm-sized liver tissue blocks were removed from 135 cadavers. All specimens underwent microscopical analysis. The tissue samples were put into a test stand, and a metal rod with a square-shaped head was pushed against the capsular surface. The force (Pmax) causing liver rupture was measured and registered with a Mecmesin AFG-500 force gauge. Six groups were formed according to the histological appearance of the liver tissue: intact (group 1), mild steatosis (group 2), moderate steatosis (group 3), severe steatosis (group 4), fibrosis (group 5), and cirrhosis (group 6). The average Pmax value was 34.1 N in intact liver samples (range from 18.1 to 60.8 N, SD ± 8.7), 45.1 N in mild steatosis (range from 24.2 to 79.8 N SD ± 12.6), 55.4 N in moderate steatosis (range from 28.9 to 92.5 N, SD ± 16.0), 57.6 N in severe steatosis (range from 39.8 to 71.5 N, SD ± 11.9), 63.7 N in fibrosis (range from 37.8 to 112.2 N, SD ± 19.5), and 87.1 N in the case of definite cirrhosis (range from 52.7 to 162.7 N, 30.3). The Pmax values were significantly higher in samples with visible structural change than in intact liver sample (p = 0.023, 0.001, 0.009, 0.0001, 0.0001 between group 1 and groups 2 to 6 respectively). Significant difference was found between mild steatosis (group 2) and cirrhosis (group 6) (p = 0.0001), but the difference between mild, moderate, and severe steatosis (groups 2, 3, and 4) was not significant. Our study demonstrated that contrary to what is expected as received wisdom dictates, the diseases of the parenchyma (steatosis and presence of fibrosis) positively correlate with the blunt force resistance of the liver tissue.

The effect of future land use changes on hydrologic ecosystem services: a case study from the Zala catchment, Hungary.

Maintaining and, where possible, improving the ecological status of our water resources are of particular importance for the future. So, one of the main drivers of landscape design must be to protect our waters. In this study, we carried out an evaluation of four hydrologic ecosystem services (HES) in the Zala River catchment area, the largest tributary of Lake Balaton (more than half of the lake's surface inflow comes from the Zala River), Hungary. The lake has great ecological, economic and social importance to the country. We used the cell-based InVEST model to quantify the spatial distribution of flood control, erosion control and nutrient retention ecosystem services for phosphorus and nitrogen; then, we carried out an aggregated evaluation. Thereby, we localized the hot spots of service delivery and tested the effect of focused land use changes in critical areas of low performance on the examined four HES. Forests proved to have the best aggregated result, while croplands near the stream network performed poorly. The modelled change in land use resulted in significant improvement on nutrient filtration and moderate to minimal but improving change for the other HES in most cases. The applied method is suitable as a supporting tool at the watershed level for decision-makers and landscape designers with the aim of protecting water bodies.

Brain death of an infant caused by a penetrating air gun injury.

Air guns are shooting projectiles (pellets) from the expansion of compressed air without involving any chemical reactions. Air guns are often regarded as harmless by the public, but these weapons can produce severe, sometimes lethal injuries, especially in children. A case of a penetrating head injury of an eleven-month-old infant, caused by an ordinary air gun pellet, is presented. The air gun pellet created an exceptionally severe brain injury, and brain death. The factors influencing the severity of air gun injuries - muzzle velocity, muzzle energy, skull thickness - are discussed.

Long-Term Stress and Concomitant Marijuana Smoke Exposure Affect Physiology, Behavior and Adult Hippocampal Neurogenesis.

Marijuana is a widely used recreational drug with increasing legalization worldwide for medical purposes. Most experimental studies use either synthetic or plant-derived cannabinoids to investigate the effect of cannabinoids on anxiety and cognitive functions. The aim of this study was to mimic real life situations where young people smoke cannabis regularly to relax from everyday stress. Therefore, we exposed young adult male NMRI mice to daily stress and concomitant marijuana smoke for 2 months and investigated the consequences on physiology, behavior and adult hippocampal neurogenesis. Animals were restrained for 6-h/day for 5-days a week. During the stress, mice were exposed to cannabis smoke for 2 × 30 min/day. We burned 2 "joints" (2 × 0.8 g marijuana) per occasion in a whole body smoking chamber. Cannabinoid content of the smoke and urine samples was measured by HPLC and SFC-MS/MS. Body weight gain was recorded daily and we did unrestrained, whole body plethysmography to investigate pulmonary functions. The cognitive performance of the animals was evaluated by the novel object recognition and Y maze tests. Anxietyrelated spontaneous locomotor activity and self-grooming were assessed in the open field test (OFT). Adult neurogenesis was quantified post mortem in the hippocampal dentate gyrus. The proliferative activity of the precursor cells was detected by the use of the exogenous marker 5-bromo-20-deoxyuridine. Treatment effects on maturing neurons were studied by the examination of doublecortin-positive neurons. Both stress and cannabis exposure significantly reduced body weight gain. Cannabis smoke had no effect on pulmonary functions, but stress delayed the maturation of several lung functions. Neither stress, nor cannabis smoke affected the cognitive functioning of the animals. Results of the OFT revealed that cannabis had a mild anxiolytic effect and markedly increased self-grooming behavior. Stress blocked cell proliferation in the dentate gyrus, but cannabis had no effect on this parameter. Marijuana smoke however had a pronounced impact on doublecortin-positive neurons influencing their number, morphology and migration. In summary, we report here that long-term stress in combination with cannabis smoke exposure can alter several health-related measures, but the present experimental design could not reveal any interaction between these two treatment factors except for body weight gain.

Suicide by Intentional Air embolism.

Venous air embolism occurs when air enters the venous system. The main causes of venous air embolism include medical procedures, neck and head trauma, and injuries of the genitals. Self-induced suicidal (and intentional) air embolism is extremely rare. The authors report a rare case of a suicidal air embolism committed using a self-made tool composed of a plastic bottle and an infusion set, injecting nearly 2000 mL of air into the cubital vein. The toxicological analysis suggested that midazolam, together with air, was also injected into the circulation using the same bottle and infusion set.

PCR-based identification of drowning: four case reports.

Proper diagnosis in drowning victims is often difficult due to the lack of signs specific to drowning. The diatom test is a widely used procedure for the diagnosis. Some types of water contain only minimal amounts of diatom cells which may provide false-negative results, while a negative diatom test result does not exclude drowning. In proving drowning, we used a polymerase chain reaction (PCR)-based biological method in addition to the conventional methods. DNA was extracted from postmortem spleen tissues and water of the drowning site. Samples were tested with algae (diatoms and small green algae)- and cyanobacteria (blue-green algae)-specific primers. We present here multiple drowning cases in which diatom tests of the postmortem tissue samples and the water were negative. In each case, the presence of phytoplanktonic DNA strengthened the autopsy diagnosis of drowning even in the absence of visible diatoms. In the future, the PCR method may be of consideration as a possible supplement of the diatom test in the examination of presumed drowning cases.

Drowning-related fatalities during a 5-year period (2008-2012) in South-West Hungary--a retrospective study.

The purpose of the present study was to investigate all the drowning-related cases in South-West Hungary between 2008 and 2012. It is a retrospective and descriptive study of 114 drowning-related deaths during that 5-year period. The investigation includes both unintentional and intentional drowning cases. We found that the most considerable risk factor of drowning in this area of Hungary is alcohol consumption, because in more than half of the cases the victims were under the influence of alcohol. We also concluded that more than two third of the cases included males. The cause of drowning in younger victims was mostly accident. In both genders subjects aged 50-70 had the highest risk of drowning in the period investigated. Seniors frequently committed suicide by drowning. Drowning deaths occurred in all types of water, mostly in lakes, rivers, canals and other types of catchment in the vicinity of victims' homes (most commonly in wells). This study might help to understand the circumstances and the causes leading to drowning and it may draw the attention to the possible preventive interventions.