What triggers a microcrack in printed engineering parts produced by selective laser sintering on the first place?

The proximity of un-melted particles within Selective Laser Sintered (SLS) printed engineering parts made of Nylon-12 is found as a major triggering effect for cracking and ultimately failure. The numerical investigation, by means of the eXtended Finite Element Method (XFEM), was performed over samples with different arrangements of un-melted particles obtained experimentally. The onset and propagation of microcracks was simulated. This included inherently how the degree of particle melt (DPM) in SLS parts affects and controls both crack initiation and propagation. The results evidenced that a microcrack started invariably between the two closest un-melted particles in all numerical tests performed considering different arrangements of un-melted particles

Asking sensitive questions using the Unmatched Count Technique: Applications and guidelines for conservation

This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordData accessibility: All data used in the analyses are freely available in the University of Oxford research archive at this link: https://ora.ox.ac.uk/objects/uuid:556a8a97-2d3d-4bf2-8fc1-359ce9786986. Data were gathered from 101 English language publications that empirically tested the UCT method. For each paper, information on 17 variables was collected, including the context (e.g. discipline, behaviour studied, rationale for using UCT, location), details of survey administration (e.g. whether a pilot study was conducted, whether design assumptions were checked), type of analysis, and comparisons to other methods (e.g. direct questions). Full data collection protocol and citations for all 101 reviewed publications are included in Appendix III and IV.1.Researchers and practitioners are increasingly using methods from the social sciences to address complex conservation challenges. This brings benefits but also the responsibility to understand the suitability and limitations of these methods in different contexts. After years of use in other disciplines, the Unmatched Count Technique (UCT) has recently been adopted by conservation scientists to investigate illegal and socially undesirable human behaviours. Here we provide guidance for practitioners and researchers on how to apply UCT effectively, and outline situations where it will be most and least appropriate. 2.We reviewed 101 publications in refereed journals that used UCT to draw conclusions on its use to date and provide recommendations on when and how to use the method effectively in conservation. In particular, we explored: type of studies undertaken (e.g. disciplines; behaviour being studied; rationale for using UCT); survey administration (e.g. sample size, pilot studies, administration mode); UCT outcomes (e.g. type of analyses, estimates, comparison with other methods); and type of recommendations. 3.We show that UCT has been used across multiple disciplines and contexts, with 10 studies that focus on conservation and natural resource use. The UCT has been used to investigate topics falling into five categories: socially undesirable behaviours, socially undesirable views, illegal or non‐compliant behaviours, socially desirable behaviours; and personal topics (e.g. being HIV positive). It has been used in 51 countries and is suitable to several situations, but limitations do exist, and the method does not always improve reporting of sensitive topics. 4.We provide best‐practice guidance to researchers and practitioners considering using UCT. We highlight that alternate methods should be considered if sample sizes are likely to be small, the behaviour in question is likely to be extremely rare, or if the behaviour is not particularly sensitive. UCT can be a useful tool for estimating the extent of non‐compliance within a conservation context, but as with all scientific investigation, careful study design, robust sampling and consistent implementation are required in order for it to be effective.Oxford Martin Programme on the Illegal Wildlife TradeNational Environment Research Council (NERC)Darwin Initiativ

Understanding the mechanisms of cooperative physico-chemical treatment and mechanical disintegration of biomass as a route for enhancing enzyme saccharification

A novel chemico-kinetic disintegration model has been applied to study the cooperative relationship between physico-chemical treatment and supplementary wet-state milling of biomass, as an efficient process route to achieve high enzyme accessibility. Wheat straw, Miscanthus and short-rotation willow were studied as three contrasting biomass species, which were subjected to controlled hydrothermal pretreatment using a microwave reactor, followed by controlled wet-state ball-milling. Comparative particle disintegration behaviour and related enzyme digestibilities have been interpreted on the basis of model parameters and with evaluation of textural and chemical differences in tissue structures, aided by the application of specific material characterisation techniques. Supplementary milling led to a 1.3×, 1.6× and 3× enhancement in glucose saccharification yield after 24 h for straw, Miscanthus and willow, respectively, following a standardised 10-min hydrothermal treatment, with corresponding milling energy savings of 98, 97 and 91% predicted from the model, compared to the unmilled case. The results confirm the viability of pretreatment combined with supplementary wet-milling as an efficient process route. The results will be valuable in understanding the key parameters for process design and optimisation and also the key phenotypical parameters for feedstock breeding and selection for highest saccharification yield

Experimental Validation of Specialised Questioning Techniques in Conservation

Conservation increasingly relies on social science tools to understand human behavior. Specialized questioning techniques (SQTs) are a suite of methods designed to reduce bias in social surveys and are widely used to collect data on sensitive topics, including compliance with conservation rules. Most SQTs have been developed in Western, industrialized, educated, rich, and democratic countries, meaning their suitability in other contexts may be limited. Whether these techniques perform better than conventional direct questioning is important for those considering their use. We designed an experiment to validate the performance of four SQTs (unmatched count technique, randomized response technique, crosswise model, and bean method) against direct questions when asking about a commonly researched sensitive behavior in conservation, wildlife hunting. We developed fictional characters, and for each method asked respondents to report the answers that each fictional character should give when asked if they hunt wildlife. We collected data from 609 individuals living close to protected areas in two different cultural and socioeconomic contexts (Indonesia and Tanzania) to quantify the extent to which respondents understood and followed SQT instructions and to explore the sociodemographic factors that influenced a correct response. Data were modeled using binomial general linear mixed models. Participants were more likely to refuse to answer questions asked using SQTs compared with direct questions. Model results suggested that SQTs were harder for participants to understand. Demographic factors (e.g., age and education level) significantly influenced response accuracy. When sensitive responses to sensitive questions were required, all SQTs (excluding the bean method) outperformed direct questions, demonstrating that SQTs can successfully reduce sensitivity bias. However, when reviewing each method, most respondents (59–89%) reported they would feel uncomfortable using them to provide information on their own hunting behavior, highlighting the considerable challenge of encouraging truthful reporting on sensitive topics. Our results demonstrate the importance of assessing the suitability of social science methods prior to their implementation in conservation contexts

Conservation publications and their provisions to protect research participants

Social science methods are increasingly applied in conservation research. However, the conservation sector has received criticism for inadequate application of ethical rigour when research involves people, particularly when investigating sensitive or illegal topics. We conducted a systematic review to investigate a) journal's ethical policies when publishing research that involves human participants, and b) the ethical safeguards documented by authors in conservation articles. Focusing on studies that used social science methods to research hunting of wildlife by local people, we reviewed 185 studies published in 57 journals. Only 37% of journals required authors to report ethical safeguards in manuscripts, and 55% of all articles reported ethical safeguards. We identified a significant mismatch between journals ethics policies and their publication practice, and found ethics were often poorly described, with insufficient detail to determine the quality of the safeguards implemented. We encourage authors to rigorously report ethical safeguards in publications. We urge journals to make ethics statements mandatory, to provide explicit guidelines to authors outlining their ethical reporting standards and to ensure compliance throughout the peer-review process. This article is protected by copyright. All rights reserved

Conservation publications and their provisions to protect research participants

Social science methods are increasingly applied in conservation research. However, the conservation sector has received criticism for inadequate application of ethical rigour when research involves people, particularly when investigating sensitive or illegal topics. We conducted a systematic review to investigate a) journal's ethical policies when publishing research that involves human participants, and b) the ethical safeguards documented by authors in conservation articles. Focusing on studies that used social science methods to research hunting of wildlife by local people, we reviewed 185 studies published in 57 journals. Only 37% of journals required authors to report ethical safeguards in manuscripts, and 55% of all articles reported ethical safeguards. We identified a significant mismatch between journals ethics policies and their publication practice, and found ethics were often poorly described, with insufficient detail to determine the quality of the safeguards implemented. We encourage authors to rigorously report ethical safeguards in publications. We urge journals to make ethics statements mandatory, to provide explicit guidelines to authors outlining their ethical reporting standards and to ensure compliance throughout the peer-review process. This article is protected by copyright. All rights reserved

Detecting deterrence from patrol data

The threat posed to protected areas by the illegal killing of wildlife is countered principally by ranger patrols that aim to detect and deter potential offenders. Deterring poaching is a fundamental conservation objective, but its achievement is difficult to identify, especially when the prime source of information comes in the form of the patrols’ own records, which inevitably contain biases. The most common metric of deterrence is a plot of illegal activities detected per unit of patrol effort against patrol effort (CPUE‐E plots). We devised a simple, mechanistic model of law‐breaking and law enforcement in which we simulated deterrence alongside exogenous changes in the frequency of offences, under different temporal patterns of enforcement effort. The CPUE‐E plots were not reliable indicators of deterrence. However, plots of change in CPUE over change in effort (ΔCPUE‐ΔE) reliably diagnosed deterrence, regardless of the temporal distribution of effort or any exogenous change in illegal activity levels, as long as the time lag between patrol effort and subsequent behavioral change among offenders was approximately known. The ΔCPUE‐ΔE plots offered a robust, simple metric for monitoring patrol effectiveness; were no more conceptually complicated than the basic CPUE‐effort plots; and required no specialist knowledge or software to produce. Our findings demonstrate the need to account for temporal autocorrelation in patrol data, and to consider appropriate (and poaching activity‐specific) intervals for aggregation. They also reveal important gaps in our understanding of deterrence in this context, especially the mechanisms by which it occurs. In view of these considerations, we provide practical recommendations for on‐the‐ground data interpretation

Asking sensitive questions using the unmatched count technique: Applications and guidelines for conservation

1.Researchers and practitioners are increasingly using methods from the social sciences to address complex conservation challenges. This brings benefits but also the responsibility to understand the suitability and limitations of these methods in different contexts. After years of use in other disciplines, the Unmatched Count Technique (UCT) has recently been adopted by conservation scientists to investigate illegal and socially undesirable human behaviours. Here we provide guidance for practitioners and researchers on how to apply UCT effectively, and outline situations where it will be most and least appropriate. 2.We reviewed 101 publications in refereed journals that used UCT to draw conclusions on its use to date and provide recommendations on when and how to use the method effectively in conservation. In particular, we explored: type of studies undertaken (e.g. disciplines; behaviour being studied; rationale for using UCT); survey administration (e.g. sample size, pilot studies, administration mode); UCT outcomes (e.g. type of analyses, estimates, comparison with other methods); and type of recommendations. 3.We show that UCT has been used across multiple disciplines and contexts, with 10 studies that focus on conservation and natural resource use. The UCT has been used to investigate topics falling into five categories: socially undesirable behaviours, socially undesirable views, illegal or non‐compliant behaviours, socially desirable behaviours; and personal topics (e.g. being HIV positive). It has been used in 51 countries and is suitable to several situations, but limitations do exist, and the method does not always improve reporting of sensitive topics. 4.We provide best‐practice guidance to researchers and practitioners considering using UCT. We highlight that alternate methods should be considered if sample sizes are likely to be small, the behaviour in question is likely to be extremely rare, or if the behaviour is not particularly sensitive. UCT can be a useful tool for estimating the extent of non‐compliance within a conservation context, but as with all scientific investigation, careful study design, robust sampling and consistent implementation are required in order for it to be effective