Microwave-assisted extraction and differential scanning calorimetry in the chemical identification of sliming agents apprehended in the south region of Brazil

Over the past decades, consume of slimming agents considerably increased in several countries, including Brazil, due to weight-loss and stimulant properties. Since these drugs are controlled to prevent illicit and indiscriminate use, there is a parallel illegal market that uses the Internet and irregular pharmacies in order to distribute these formulations. Slimming agents produced by these illegal sources are known for being manufactured with little or none quality control resulting in uncertain and unknown formulations. For forensic purposes, apprehended pharmaceuticals have to undergo a process of chemical identification that can be difficult due to its complex matrix. In this sense, application of assisted energies in the extraction step such as microwave irradiation can be a promising method to increase the recuperation of the target molecules of the sample. Therefore, the aim of this research was to identify four slimming agents apprehended in Brazil by means of visual inspection, Fourier Transform Infrared Spectroscopy, Differential Scanning Calorimetry and Gas Chromatography – Mass Spectrometry. Moreover, the efficiency of solid-liquid extraction and microwave-assisted extraction was compared. It should be noted that our work was one of the few to use Differential Scanning Calorimetry and the application of microwave irradiation in the analysis of apprehended materials. Results showed that the majority of the samples was counterfeit being composed of one or several adulterants or contaminants. Initially, visual inspection resourcefully screened the slimming agents for possible signs of falsification, however it failed to detect fraudulent products that were very similar to veridical medicines. Sequentially, Fourier Transform Infrared Spectroscopy detected functional groups present in the samples while the presence or absence of the alleged active ingredients were successfully measured with Differential Scanning Calorimetry and, thus, providing a full chemical screening of the apprehended materials. Gas Chromatography- Mass Spectrometry confirmed the presence of adulterants such as caffeine, fluoxetine and phenolphthalein as well as contaminants such as sulfurol in the falsified samples. Finally, comparison of extraction procedures indicated that microwave-assisted extraction increased the recovery of compounds detected in chromatographic analysis to a greater extent than solid-liquid extraction.     

Can analysis of a small clod of soil help to solve a murder case?

Soil forensics utilizes extensive soil information to answer legal questions and test hypotheses. The main difficulty often is the determination of different variables from a small amount of soil sample collected on the suspect. We developed a sequential mineralogical and chemical analyses to assess a limited quantity of soil vestiges (0.5 g) from a suspect's vehicle (adhered to the outside rear-view mirror and to the left front fender) involved in a murder case and compared them with the surface samples found at the victim's body disposal site at the Graciosa Road, Paraná State, Brazil. All results affirm that the suspect’s vehicle could have been in contact with the edge of the Graciosa Road, approximately the place where the victim’s body was located. As a result of the soil analysis and comparison, the results support the likely contact of the suspect’s vehicle with the crime scene.     

Warning behaviors and leaked intent: Potential new avenues to prevent mass shootings

On March 12, 2018, John Laubscher, owner of AJ’s Archery in Nelson, NY, had a gut feeling and refused to sell a rifle to a Syracuse University student—disrupting a mass shooting ( https://www.syracuse.com/crime/2018/04/how_gun_shop_owner_thwarted_on_the_edge_su_student_from_buying_high-capacity_rif.html . Accessed 10 Nov 2021). Prompted by this, we surveyed the opinions, beliefs, attitudes, and current practices of gun sellers in Onondaga County, NY, in regard to safe gun sales. The primary outcome was to determine which types of “concerning behaviors” are more likely to cause a seller to intervene in some manner. Secondary outcomes included the following: ascertaining the frequency of denials of customer purchases, frequency of reporting to law enforcement, and identifying any gaps that make it difficult for gun sellers to report behaviors to the authorities. Follow-up interviews were conducted with those who were willing to speak with the authors in more depth. A response rate of 12.9% was achieved. Sixty-two percent (62.5%) of respondents had some experience in uniformed services, with specialized training in mental or emotional crises, as well as deception detection. The majority found the training helpful in their gun selling career. Reasons for personal denials were reported as: “interest in illegal fittings,” “information revealed during conversation,” and “lack of basic knowledge of using the firearm looking to purchase.” Two respondents stated that due to a lack of a “reporting protocol,” they would not report any concerns to law enforcement. The study helps inform future research in regard to surveying more sellers across NY state and nationwide.     

Identification of gunshot residues in fabric targets using sector field inductively coupled plasma mass spectrometry technique and ternary graphs

During criminal investigations involving firearms, the detection of gunshot residues (GSRs) is one of the most important evidences. In the present study, a new method to identify trace evidences of GSRs, deposited around the bullet entrance hole, in different types of fabrics used as targets, is described. The experiments were carried out using a 0.38-inch caliber revolver, and 9-mm and 0.40-inch caliber pistols. Testimonies of 2.25 cm(2) of the fabrics were cut around the bullet entrance and digested with 10% nitric acid. Antimony, barium, and lead were analyzed in the remaining solution using a sector field inductively coupled plasma mass spectrometer. The concentrations of the elements were detected at levels up to few microgram per square centimeter. The use of ternary graphics allowed us to identify specific patterns of distribution for blank samples and the clear distinction between the revolver and pistols used.     

Reconstructing shredded documents through feature matching

We describe a procedure for reconstructing documents that have been shredded by hand, a problem that often arises in forensics. The proposed method first applies a polygonal approximation in order to reduce the complexity of the boundaries and then extracts relevant features of the polygon to carry out the local reconstruction. In this way, the overall complexity can be dramatically reduced because few features are used to perform the matching. The ambiguities resulting from the local reconstruction are resolved and the pieces are merged together as we search for a global solution. The preliminary results reported in this paper, which take into account a limited amount of shredded pieces (10-15) demonstrate that feature-matching-based procedure produces interesting results for the problem of document reconstruction.     

Reconstructing shredded documents through feature matching

We describe a procedure for reconstructing documents that have been shredded by hand, a problem that often arises in forensics. The proposed method first applies a polygonal approximation in order to reduce the complexity of the boundaries and then extracts relevant features of the polygon to carry out the local reconstruction. In this way, the overall complexity can be dramatically reduced because few features are used to perform the matching. The ambiguities resulting from the local reconstruction are resolved and the pieces are merged together as we search for a global solution. The preliminary results reported in this paper, which take into account a limited amount of shredded pieces (10–15) demonstrate that feature-matching-based procedure produces interesting results for the problem of document reconstruction.     

Error Rates in Forensic Child Sexual Abuse Evaluations

When mental health, medical, and social work professionals and paraprofessionals make false positive or false negative errors in their judgments about the validity of allegations of child sexual abuse, the consequences can be catastrophic for the affected children and adults. Because of the high stakes, practitioners, legal decision makers, and policy makers should have some idea of the magnitude and variability of error rates in this domain. A novel approach was used to estimate individual error rates for 110 professionals (psychologists, physicians, social workers, and others) who conduct or participate in forensic child sexual abuse evaluations. The median estimated false positive and false negative error rates were 0.18 and 0.36, respectively. Estimated error rates varied markedly from one participant to the next. For example, the false positive error rate estimates ranged from 0.00 to 0.83. These estimates are based on participants’ self-reported substantiation rates and on their subjective frequency distributions for the probability of truth for the abuse allegations they evaluate.     

The Catch-up Strategy of Petrobrás through Cooperative R&D

This article seeks to reflect on the possibilities of cooperative R&D to constitute an opportunity for companies in developing countries to take part in the innovation concerning technological frontier. In order to show this thesis can be true, this article is based on the case study of Petrobrás, the Brazilian state-owned oil company, which has employed the resource of cooperative R&D to gain access to the new subsea boosting technology and to acquire a place in the vanguard of such technology. However, the catch-up occurs only when firms in developing countries actively take part in the innovation process and accomplish an efficient process of technological learning, which is reflected on the evolution of interactions with external partners. The experience of Petrobrás is analyzed emphasizing the technological learning process through the transformation in its agreements with external partners. We present three cases of subsea boosting technologies developed by Petrobrás together with a majority of foreign producers or institutes. The analysis of these experiences allows us to show that the learning process and the mastery of in-house processes were accompanied by a significant evolution in the agreements with external sources. Petrobrás passes on from the position of cosponsor to that of articulator of the innovation process in technological cooperation agreements. The article proposes an evolutionary sequence to analyze the company's learning process. The evolutionary trajectories are different in each case, but in all of them it was possible to prove the increasing commitment of Petrobrás to the innovation effort.