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Gallium nitride on silicon (GaN/Si) is an important technological approach for power electronic devices exhibiting superior performance compared to devices based on a pure silicon technology. However, the material defect density in GaN/Si is high, and identification of critical defects limiting device reliability is still only partially accomplished because of experimental difficulties. In this work, atomic force microscopy, scanning electron microscopy, secondary ion mass spectrometry, and cathodoluminescence were employed to investigate commonly occurring epitaxial overgrown V-pits and inhomogeneous incorporation of oxygen and carbon across layer stacking in the vertical direction. These experiments identified V-pits as regions with higher n-type carrier concentrations and paths for vertical leakage through the buffer, as directly probed by conductive atomic force microscopy. The deleterious effect of V-pits on device performance is demonstrated by evaluating test devices fabricated on two wafers with significantly diverse density of buried V-pits induced by varying growth conditions of the aluminum nitride nucleation layer. A clear correlation between observed vertical breakdown and density of V-pits within the C-doped GaN layer below the device structures is obtained. Back-gating transient measurements also show that the dynamic device behavior is affected by the V-pit density in terms of the detrapping time constants. [ABSTRACT FROM AUTHOR]

In this work, an AlGaN/GaN-HEMT heterostructure is exemplarily studied by a strict place-to-place correlational approach in order to help clarify some open questions in the wide field of reliability topics. Especially, vertical leakage current, its relation to dislocations in general, and specific types in particular are investigated on a highly defective material. With the aid of atomic force microscopy (AFM) in tapping mode, cathodoluminescence imaging, defect selective etching, and energy dispersive X-ray, the material's defect content around the device relevant two dimensional electron gas is analyzed. The total dislocation density, as well as the density of threading screw, edge, and mixed type dislocations, is systematically investigated directly. The obtained result is statistically much more significant than is possible by conventional transmission electron microscopy studies and more precise than the results obtained by the indirect method of rocking curve analysis. The method of conductive AFM allowed mapping of variations in the vertical leakage current, which could be correlated with variations in barrier leakage or gate leakage. Spots of locally high leakage current could be observed and directly assigned to dislocations with a screw component, but with significant differences even within the same group of dislocation types. The electrical activity of dislocations is discussed in general, and a fundamental model for a potential dislocation driven vertical leakage is proposed. [ABSTRACT FROM AUTHOR]

The Pale di San Martino and Pale di San Lucano (referred to together as the 'Pale') are remnants of an originally more extensive carbonate platform in the Dolomite Mountains of northern Italy. The platforms are composed of Middle Triassic dolomites and limestones up to 1.6km thick. Limestones comprise 2-3% of the platform carbonates and are restricted to narrow corridors (tens to a few hundred metres wide, hundreds of metres long and high) within the dolomite. The mainly sucrosic dolomites of the Pale are interpreted as the result of recrystallization of a depositional, nearly stoichiometric Mg calcite under burial temperatures of ca. 40-70°C. The principal arguments are: The quantitative composition indicates that all platform carbonates are composed mainly of micritic crusts (45%; boundstone fabric prevails) and early cement (35%; microcrystalline, fibrous). The platform carbonates were probably mainly bacterial precipitates and tight at the sediment-water interface (porosities <5%, permeabilities in the micro-Darcy range)., The limestone-dolomite transitions (centimetres to decimetres wide) lack dolomite gradients. The lack of evidence for flowing fluids causing dolomitization suggests stagnant pore waters., The δ13C of average dolomite is 1.3‰ heavier than that of coeval limestone (666 analyses). The difference corresponds to a primary difference of 50mol% MgCO3 and is interpreted as the result of fractionation. It suggests a dolomite precursor of very high Mg calcite, whereas present-day limestone of the Pale was probably deposited as a basically Mg-free polymorph (aragonite and/or calcite)., The dolomite δ18O (+1 to −11‰ VPDB) values show a scatter over the platform thickness and preserve randomly distributed values around 0‰. The scatter is probably due to selective re-setting of δ18O near pore spaces and is mainly a sampling effect., The observation that 87Sr/86Sr ratios (77 analyses) of limestone and dolomite are either slightly higher or lower than Middle Triassic seawater, but almost never 'normal marine', suggests that the platform carbonates of the Pale were deposited from seawater contaminated with artesian freshwater. The limestone corridors are probably caused by artesian springs of somewhat higher than ambient depositional temperature, with low Mg calcite and/or aragonite deposited in or near fracture zones. The volumetrically subordinate cycle-cap dolomite is possibly a primary precipitate. [ABSTRACT FROM AUTHOR]

Background: Stress levels and the prevalence of mental disorders in the general population have been rising in recent years. Chatbot-based interventions represent novel and promising digital approaches to improve health-related parameters. However, there is a lack of research on chatbot-based interventions in the area of mental health., Objective: The aim of this study was to investigate the effects of a 3-week chatbot-based intervention guided by the chatbot ELME, specifically with respect to the ability to reduce stress and improve various health-related parameters in a stressed sample., Methods: In this multicenter two-armed randomized controlled trial, 118 individuals with medium to high stress levels were randomized to the intervention group (n=59) or the treatment-as-usual control group (n=59). The ELME chatbot guided participants of the intervention group through 3 weeks of training based on the topics stress, mindfulness, and interoception, with practical and psychoeducative elements delivered in two daily interactive intervention sessions via a smartphone (approximately 10-20 minutes each). The primary outcome (perceived stress) and secondary outcomes (mindfulness; interoception or interoceptive sensibility; subjective well-being; and emotion regulation, including the subfacets reappraisal and suppression) were assessed preintervention (T1), post intervention (T2; after 3 weeks), and at follow-up (T3; after 6 weeks). During both conditions, participants also underwent ecological momentary assessments of stress and interoceptive sensibility., Results: There were no significant changes in perceived stress (β 03 =-.018, SE=.329; P=.96) and momentary stress. Mindfulness and the subfacet reappraisal significantly increased in the intervention group over time, whereas there was no change in the subfacet suppression. Well-being and momentary interoceptive sensibility increased in both groups over time., Conclusions: To gain insight into how the intervention can be improved to achieve its full potential for stress reduction, besides a longer intervention duration, specific sample subgroups should be considered. The chatbot-based intervention seems to have the potential to improve mindfulness and emotion regulation in a stressed sample. Future chatbot-based studies and interventions in health care should be designed based on the latest findings on the efficacy of rule-based and artificial intelligence-based chatbots., Trial Registration: German Clinical Trials Register DRKS00027560; https://drks.de/search/en/trial/DRKS00027560., International Registered Report Identifier (irrid): RR2-doi.org/10.3389/fdgth.2023.1046202., (©Christine Schillings, Echo Meißner, Benjamin Erb, Eileen Bendig, Dana Schultchen, Olga Pollatos. Originally published in JMIR Mental Health (https://mental.jmir.org), 28.05.2024.)

An environmentally responsive root system is crucial for plant growth and crop yield, especially in suboptimal soil conditions. This responsiveness enables the plant to exploit regions of high nutrient density while simultaneously minimizing abiotic stress. Despite the vital importance of root systems in regulating plant growth, significant gaps of knowledge exist in the mechanisms that regulate their architecture. Auxin defines both the frequency of lateral root (LR) initiation and the rate of LR outgrowth. Here, we describe a search for proteins that regulate root system architecture (RSA) by interacting directly with a key auxin transporter, PIN1. The native separation of Arabidopsis plasma membrane protein complexes identified several PIN1 co-purifying proteins. Among them, AZG1 was subsequently confirmed as a PIN1 interactor. Here, we show that, in Arabidopsis, AZG1 is a cytokinin (CK) import protein that co-localizes with and stabilizes PIN1, linking auxin and CK transport streams. AZG1 expression in LR primordia is sensitive to NaCl, and the frequency of LRs is AZG1-dependent under salt stress. This report therefore identifies a potential point for auxin:cytokinin crosstalk, which shapes RSA in response to NaCl., (© 2023 The Authors New Phytologist © 2023 New Phytologist Foundation.)

Aim: Comparison of injuries to the facial and cerebral parts of the skull causing death and grievous bodily harm, resulting solely from punches to the facial area of the skull. Assessment and confrontation of both groups in terms of the final criminal-legal classification of the perpetrator's acts. Review of reasons for court judgements with a focus on the subjective elements of the prohibited act. Attempt to verify the hypothesis assuming that death or grievous bodily harm can be caused by a single punch to the facial part of the skull., Material and Methods: Final judgements passed by criminal divisions of common courts of law in cases where death or grievous bodily harm was caused by injuries to the facial and cerebral parts of the skull resulting solely from punches to the facial area of the skull. Assessment of individual cases within each group to determine similarities and differences. Comparative analysis of both groups., Results: The cause of death in cases involving injuries to the facial part of the skull was rapid suffocation following blood aspiration into the respiratory tract. However, the criminal-legal classification of the perpetrators' actions in these cases was varied. In one case, death resulted from injuries to the cerebral part of the skull, which are extremely rare as a result of a punch to the facial area within the skull. Grievous bodily harm was due to the loss of vision in the eye, typically due to eyeball rupture., Conclusions: Even though the circumstances of the injuries were similar, different mechanisms were responsible for causing death and grievous bodily harm in the victims. The most severe consequences (death and grievous bodily harm) were not caused by injuries of the same type in any of the cases studied. A single punch to the facial part of the skull may be enough to lead to either grievous bodily harm or death, but the criminal-legal assessment of punching to the face can vary greatly., Competing Interests: The authors report no conflicts of interest in this work., (Copyright © 2021 by PTMSiK.)

GaN epitaxially grown on Si is a material for power electronics that intrinsically shows a high density of dislocations. We show by Conductive Atomic Force Microscopy (C-AFM) and Defect Selective Etching that even for materials with similar total dislocation densities substantially different subsets of dislocations with screw component act as current leakage paths within the AlGaN barrier under forward bias. Potential reasons are discussed and it will be directly shown by an innovative experiment that current voltage forward characteristics of AlGaN/GaN Schottky diodes shift to lower absolute voltages when such dislocations are present within the device. A local lowering of the Schottky barrier height around conductive dislocations is identified and impurity segregation is assumed as responsible root cause. While dislocation related leakage current under low reverse bias could not be resolved, breakdown of AlGaN/GaN Schottky diodes under high reverse bias correlates well with observed conductive dislocations as measured by C-AFM. If such dislocations are located near the drain side of the gate edge, failure of the gate in terms of breakdown or formation of percolation paths is observed for AlGaN/GaN high electron mobility transistors.

The aim of this work is to demonstrate high breakdown voltage and low buffer trapping in superlattice GaN-on-Silicon heterostructures for high voltage applications. To this aim, we compared two structures, one based on a step-graded (SG) buffer (reference structure), and another based on a superlattice (SL). In particular, we show that: (i) the use of an SL allows us to push the vertical breakdown voltage above 1500 V on a 5 µm stack, with a simultaneous decrease in vertical leakage current, as compared to the reference GaN-based epi-structure using a thicker buffer thickness. This is ascribed to the better strain relaxation, as confirmed by X-Ray Diffraction data, and to a lower clustering of dislocations, as confirmed by Defect Selective Etching and Cathodoluminescence mappings. (ii) SL-based samples have significantly lower buffer trapping, as confirmed by substrate ramp measurements. (iii) Backgating transient analysis indicated that traps are located below the two-dimensional electron gas, and are related to C N defects. (iv) The signature of these traps is significantly reduced on devices with SL. This can be explained by the lower vertical leakage (filling of acceptors via electron injection) or by the slightly lower incorporation of C in the SL buffer, due to the slower growth process. SL-based buffers therefore represent a viable solution for the fabrication of high voltage GaN transistors on silicon substrate, and for the simultaneous reduction of trapping processes.

AlN slices from bulk crystals grown under low thermomechanical stress conditions via the physical vapor transport (PVT) method were analyzed by X-ray methods to study the influence of the growth mode on the crystal quality. Defect types and densities were analyzed along axial [0001] as well as lateral growth directions. X-ray diffraction (0110) rocking-curve mappings of representative wafer cuts reveal a low mean FWHM of 13.4 arcsec, indicating the generally high crystal quality. The total dislocation density of 2 × 10 3  cm -2 as determined by X-ray topography is low and dislocations are largely threading edge dislocations of b = 1/3〈1120〉 type. The absence of basal plane dislocations in homogeneous crystal regions void of macroscopic defects can be linked to the low-stress growth conditions. Under the investigated growth conditions this high crystal quality can be maintained both along the axial [0001] direction and within lateral growth directions. Exceptions to this are some locally confined, misoriented grains and defect clusters, most of which are directly inherited from the seed or are formed due to the employed seed fixation technique on the outer periphery of the crystals. Seed-shaping experiments indicate no apparent kinetic limitations for an enhanced lateral expansion rate and the resulting crystal quality, specifically with regard to the growth mode on a -face facets., (© Thomas Wicht et al. 2020.)

We investigated the origin of vertical leakage and breakdown in GaN-on-Si epitaxial structures. In order to understand the role of the nucleation layer, AlGaN buffer, and C-doped GaN, we designed a sequential growth experiment. Specifically, we analyzed three different structures grown on silicon substrates: AlN/Si, AlGaN/AlN/Si, C:GaN/AlGaN/AlN/Si. The results demonstrate that: (i) the AlN layer grown on silicon has a breakdown field of 3.25 MV/cm, which further decreases with temperature. This value is much lower than that of highly-crystalline AlN, and the difference can be ascribed to the high density of vertical leakage paths like V-pits or threading dislocations. (ii) the AlN/Si structures show negative charge trapping, due to the injection of electrons from silicon to deep traps in AlN. (iii) adding AlGaN on top of AlN significantly reduces the defect density, thus resulting in a more uniform sample-to-sample leakage. (iv) a substantial increase in breakdown voltage is obtained only in the C:GaN/AlGaN/AlN/Si structure, that allows it to reach V BD > 800 V. (v) remarkably, during a vertical I-V sweep, the C:GaN/AlGaN/AlN/Si stack shows evidence for positive charge trapping. Holes from C:GaN are trapped at the GaN/AlGaN interface, thus bringing a positive charge storage in the buffer. For the first time, the results summarized in this paper clarify the contribution of each buffer layer to vertical leakage and breakdown.

Introduction: The role of TOMM40-APOE 19q13.3 region variants is well documented in Alzheimer's disease (AD) but remains contentious in dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD)., Methods: We dissected genetic profiles within the TOMM40-APOE region in 451 individuals from four European brain banks, including DLB and PDD cases with/without neuropathological evidence of AD-related pathology and healthy controls., Results: TOMM 40 -L/ APOE -ε4 alleles were associated with DLB (OR TOMM40 - L  = 3.61; P value = 3.23 × 10 -9 ; OR APOE -ε4  = 3.75; P value = 4.90 × 10 -10 ) and earlier age at onset of DLB (HR TOMM40 -L  = 1.33, P value = .031; HR APOE -ε4  = 1.46, P value = .004), but not with PDD. The TOMM40 -L/ APOE -ε4 effect was most pronounced in DLB individuals with concomitant AD pathology (OR TOMM40 -L  = 4.40, P value = 1.15 × 10 -6 ; OR APOE - ε 4  = 5.65, P value = 2.97 × 10 -8 ) but was not significant in DLB without AD. Meta-analyses combining all APOE -ε4 data in DLB confirmed our findings (OR DLB  = 2.93, P value = 3.78 × 10 -99 ; OR DLB+AD  = 5.36, P value = 1.56 × 10 -47 )., Discussion: APOE -ε4/ TOMM 40 -L alleles increase susceptibility and risk of earlier DLB onset, an effect explained by concomitant AD-related pathology. These findings have important implications in future drug discovery and development efforts in DLB., (© 2019 The Authors.)

Introduction: Synthetic cannabinoids are currently the largest group of new psychoactive substances. Those that have been subjected to legal control are replaced by newer uncontrolled substances, which causes constant and dynamic changes to the drug market. Some of the most recent synthetic cannabinoids that have appeared on the "legal highs" market are AMB-FUBINACA and EMB-FUBINACA. Case history: A 27-year-old man was found dead on a bed in an apartment. At autopsy, congestion of internal organs, pulmonary oedema and left-sided pleural adhesions were found. The medical examiner concluded that the man died due to acute respiratory failure. The autopsy materials (blood, urine, liver, kidney, stomach, intestine, lung and brain) were collected for further toxicological analyses. Methods: The synthetic cannabinoids AMB-FUBINACA and EMB-FUBINACA were isolated from autopsy materials by precipitation with acetonitrile. The quantitative analyses were carried out by LC-MS/MS. Results: AMB-FUBINACA and EMB-FUBINACA were detected and quantified in all post-mortem materials except the blood. The determined concentrations of these compounds in solid tissues were in the range of 0.2-0.9 ng/g and 0.2-3.5 ng/g. The highest concentrations of AMB-FUBINACA and EMB-FUBINACA were revealed in the stomach content (5.8 and 36.2 ng/mL, respectively). Discussion: The presented case demonstrates that even in cases of fatalities, it is possible that the parent substance will not be present in the blood, while being present in other autopsy materials. The determined concentrations of the compounds may indicate oral administration of synthetic cannabinoids. It can also be assumed that AMB-FUBINACA and EMB-FUBINACA probably contributed to death. Conclusion: The presented case shows that synthetic cannabinoids can be undetected in the blood of even seriously or fatally intoxicated people. This situation means that the analysis of only blood samples may not confirm poisoning. The presented case also suggests that AMB-FUBINACA and EMB-FUBINACA use is dangerous to health and may lead to fatal intoxication.

Aim of the Study: The aim of the study was to evaluate the prevalence of effects equivalent to moderate and severe impairment to health within the meaning of the Penal Code in patients with zygomatico-maxillo-orbital fractures and isolated orbital floor fractures. In addition, the study addressed the possibilities of applying the presented results in the preparation of medicolegal opinions in cases provided for in Articles 158 and 160 of the PC with respect to evaluating the plausibility of inflicting such bodily injuries and causing moderate and severe health impairment., Material and Methods: The study covered a total of 124 patients operated on in the then Clinic of Cranio-Maxillofacial Surgery, Medical Academy of Lodz, in 1996-2001, because of fractures involving the inferior orbital wall including zygomatico-maxillo-orbital fractures (95 cases) and isolated orbital floor fractures (29 cases). The group was analyzed in a statistical and descriptive manner., Results: All the study patients (100%) with both types of fractures involving the inferior orbital wall exhibit symptoms and disorders which, pursuant to the PC, would constitute at least moderate, or possibly even severe, impairment to health., Conclusions: Punches or kicks to the orbital region create a real danger of causing both types of orbital fracture under study, and resulting in at least moderate health impairment.

Aim of the Study: The aim of the paper is analysis of the impact of immobilization treatment of "less severe" motor organ injuries affecting soft tissues on the position of medical experts and court decisions in crimes against health. We also analysed the attitude of courts to expert opinions and present a proposal for a model of judicial and medical opinion in such cases., Material and Methods: In the study, we analysed judgments of the criminal divisions of common courts, in which the use of medical immobilization of a given part of the body or lack thereof could have an impact on the degree of health impairment determined by the medical expert., Results: Some experts consider medical immobilization to be tantamount to an impairment of the function of a body organ, and the courts rarely reject such opinions. For some experts, the key is not the actual function of the immobilized part of the musculoskeletal system after 7 days from injury, but the immobilization treatment itself, and not the time it takes. In addition, experts determine the severity of injuries when immobilization is/is not used., Conclusions: The degree of health impairment, as defined in the Penal Code, should be determined by a medical check-up carried out 7 days after the injury, with an assessment of its "biological" effects, and not by the use of immobilization treatment and the time for which it is maintained.

Incorrect declaration of death is not a frequent situation in medico-legal reports, and such cases are usually of great interest. In this study the authors present a case of improper declaration of death by a physician, despite the absence of early definitive signs of death and without a full medical examination. However, the investigation of the case was dropped, and the conduct of the physician was not assessed by experts.

The paper presents the case of an unexplained and the most mysterious death in the history of Polish Tatra tourism. It concerns three people of different ages and occurred on August 3, 1925 in the Valley of Jaworowa. Kazimierz Kasznica, his son Wacław Kasznica and a newly discovered mountaineer Ryszard Wasserberger died suddenly for unknown reasons in 15 minutes during a mountain trek. This story is interesting due to the mysterious, simultaneous death of three people of different ages and due to the fact that Waleria Kasznica - the wife of Kazimierz and the mother of Wacław Kasznica survived the journey. KEY WORDS.

In this paper, we report a failure case of blue LEDs returned from a field application, and propose a practical way to identify the physical and structural reasons for the observed malfunction by a combination of different electron microscope techniques. Cathodoluminescence imaging and electron beam induced current (EBIC) imaging are employed in order to visualize conductive paths through the device in conjunction with subsequent energy dispersive x-ray analysis (EDS), revealing a metal deposition along cracks in the semiconductor layer which short-circuit the device. We demonstrate that the electron beam induced current imaging, in conjunction with other microscopic and analytical techniques at µm scale, is a powerful combination for clearly resolving and visualizing the cause of failure in the GaN LED chip. However, this represents a case study of a real application, which may not have been generally observed in laboratory testing environment., Competing Interests: The authors declare no conflict of interest.

Objective: This study investigated the different facets of job satisfaction that influence community care and residential care employees' intention to stay in the aged care workforce., Methods: A survey of four organisations in Australia was undertaken. t-Tests were conducted to analyse differences between groups. Regression analyses were performed to examine the factors influencing intentions to stay in the workforce., Results: Community care workers were more satisfied with various facets of job satisfaction including work on their present job, supervision, people in their present job and the job in general. There was a difference between how the various facets of job satisfaction influenced intentions to stay for residential care compared to community care workers., Conclusions: Both workers were satisfied with their work conditions and work to different extents. There is an opportunity for residential care to look to the practices within the community care sector to improve employees' intentions to stay., (© 2017 AJA Inc.)

A rare variant in TREM2 (p.R47H, rs75932628) was recently reported to increase the risk of Alzheimer's disease (AD) and, subsequently, other neurodegenerative diseases, i.e. frontotemporal lobar degeneration (FTLD), amyotrophic lateral sclerosis (ALS), and Parkinson's disease (PD). Here we comprehensively assessed TREM2 rs75932628 for association with these diseases in a total of 19,940 previously untyped subjects of European descent. These data were combined with those from 28 published data sets by meta-analysis. Furthermore, we tested whether rs75932628 shows association with amyloid beta (Aβ42) and total-tau protein levels in the cerebrospinal fluid (CSF) of 828 individuals with AD or mild cognitive impairment. Our data show that rs75932628 is highly significantly associated with the risk of AD across 24,086 AD cases and 148,993 controls of European descent (odds ratio or OR = 2.71, P = 4.67 × 10(-25)). No consistent evidence for association was found between this marker and the risk of FTLD (OR = 2.24, P = .0113 across 2673 cases/9283 controls), PD (OR = 1.36, P = .0767 across 8311 cases/79,938 controls) and ALS (OR = 1.41, P = .198 across 5544 cases/7072 controls). Furthermore, carriers of the rs75932628 risk allele showed significantly increased levels of CSF-total-tau (P = .0110) but not Aβ42 suggesting that TREM2's role in AD may involve tau dysfunction., (Copyright © 2015 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.)

Aim: This study examined the importance and performance of middle managers' skills to provide a starting point for a sector-wide leadership and management framework., Background: There is an increasing consensus that the quality of management, leadership and performance of any organisation is directly linked to the capabilities of its middle managers and the preparation and on-going training they receive., Method: A total of 199 middle managers from three aged care organisations in Australia participated in a questionnaire conducted during 2010-2011., Result: This study found that middle managers perceived the need to develop their communication skills, self-awareness, change management, conflict resolution and leadership skills., Conclusion: Middle managers perceive a discrepancy between performance and importance of various managerial skills. This study demonstrated that provision of training needs to go beyond clinical skills development and further investigation into managers' needs is necessary, particularly considering the diversity of this critical group in organisations., Implications for Nursing Management: Future training opportunities provided to middle managers need to address the 'softer' skills (e.g. communication) rather than 'technical' skills (e.g. clinical skills). The provision of training in these skills may improve their performance, which may also lead to increased job satisfaction, continuity in leadership and management and ultimately improvements in the quality of care provided., (© 2014 John Wiley & Sons Ltd.)

A rare case of death of a young man due to airway obstruction in the course of angioedema (Quincke's edema). Type I hereditary angioedema due to C1 esterase inhibitor deficiency had been diagnosed in the man while he was alive. The information concerning the man's health state was given in the Public Prosecutor's decision ordering medico legal autopsy, which was extremely helpful in recognizing the cause of death., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)