2,080 research outputs found
Explainability in AI Policies: A Critical Review of Communications, Reports, Regulations, and Standards in the EU, US, and UK
Public attention towards explainability of artificial intelligence (AI) systems has been rising in recent years to offer methodologies for human oversight. This has translated into the proliferation of research outputs, such as from Explainable AI, to enhance transparency and control for system debugging and monitoring, and intelligibility of system process and output for user services. Yet, such outputs are difficult to adopt on a practical level due to a lack of a common regulatory baseline, and the contextual nature of explanations. Governmental policies are now attempting to tackle such exigence, however it remains unclear to what extent published communications, regulations, and standards adopt an informed perspective to support research, industry, and civil interests. In this study, we perform the first thematic and gap analysis of this plethora of policies and standards on explainability in the EU, US, and UK. Through a rigorous survey of policy documents, we first contribute an overview of governmental regulatory trajectories within AI explainability and its sociotechnical impacts. We find that policies are often informed by coarse notions and requirements for explanations. This might be due to the willingness to conciliate explanations foremost as a risk management tool for AI oversight, but also due to the lack of a consensus on what constitutes a valid algorithmic explanation, and how feasible the implementation and deployment of such explanations are across stakeholders of an organization. Informed by AI explainability research, we then conduct a gap analysis of existing policies, which leads us to formulate a set of recommendations on how to address explainability in regulations for AI systems, especially discussing the definition, feasibility, and usability of explanations, as well as allocating accountability to explanation providers
Polarization shaping for control of nonlinear propagation
We study the nonlinear optical propagation of two different classes of
space-varying polarized light beams -- radially symmetric vector beams and
Poincar\'e beams with lemon and star topologies -- in a rubidium vapour cell.
Unlike Laguerre-Gauss and other types of beams that experience modulational
instabilities, we observe that their propagation is not marked by beam breakup
while still exhibiting traits such as nonlinear confinement and self-focusing.
Our results suggest that by tailoring the spatial structure of the
polarization, the effects of nonlinear propagation can be effectively
controlled. These findings provide a novel approach to transport high-power
light beams in nonlinear media with controllable distortions to their spatial
structure and polarization properties.Comment: 5 pages, and 4 figure
Electric Hybrid Powertrain for Armored Vehicles
The performance of modern, new generation-armored vehicles would greatly benefit from overall engineering, optimization, and integration techniques of advanced diesel engines-electrified transmissions. Modern axial flux electric motors and controllers are perfectly able to replace the classical automatic gearbox and complex steering system of traditional Main Battle Tanks. This study shows a possible design of a serial hybrid electric power pack for very heavy tanks with a weight well over 50 tons. The result is a hybrid power system that improves the overall performance of armored vehicles off-road and on-road, improving the acceleration and the smoothness of the ride. In addition, fuel consumption will be reduced because the internal combustion engine operates at fixed rpm. The electric motors will outperform the traditional engines due to their very high torque output even at “zero speed”. The weight of a hybrid system has also been calculated. In fact, in many cases, it is possible to use all off-the-shelf components. The on-board diagnosis of the subsystems in the hybrid powertrain makes it possible to achieve a Time Between Overhaul (TBO) of 4500 h with a failure probability inferior to one in 10,000
Beyond Silos: A Call to Include Hospital Support Staff in Cultural Competency Training
Context: Patient populations are becoming more diverse. As a result, the “one-size fits all” approach to healthcare delivery is no longer sufficient. Today, quality of care is highly influenced by the cultural competency (CC) of healthcare providers (HCPs). HCPs, however, are not the only members of hospital staff who influence quality of care. Another group, hospital support staff (HSS), also play a critical role in the healthcare delivery process. Yet, HSS remain under-recognized and have been left out of hospital-led CC training.Aim: This policy brief offers a novel perspective, advocating for the inclusion of HSS in hospital-led CC training, as it has been acknowledged by previous research that increasing the CC of healthcare staff is an appropriate strategy to improve the quality of care for patients.Methods: To gain more insight, interviews and surveys were conducted (October 2022) among a group of HSS at the Ronald McDonald House (RDMH). These HSS include volunteers and managers who enable Family Centred Care (FCC) for Maastricht University Medical Centre (MUMC+). A non-systematic literature review on the topic of cultural competency development was also conducted.Results: To develop policy recommendations, options were first assessed using a pre-established framework for developing organisational CC by Castillo & Guo (10). In addition, a stakeholder analysis was completed. Together with the survey responses and interviews, this confirmed HSS, need and want to be culturally competent. These results feed into the development of policy recommendations.
Recommendations:Thus, three policy recommendations are made: (1) formalise CC training at MUMC+; (2) include HSS in such a CC training; and (3) develop and monitor training with Participatory Action Research (PAR)
'Give Me Structure':Synthesis and Evaluation of a (Network) Threat Analysis Process Supporting Tier 1 Investigations in a Security Operation Center
Current threat analysis processes followed by tier-1 (T1) analysts in a Security Operation Center (SOC) rely mainly on tacit knowledge, and can differ greatly across analysts. The lack of structure and clear objectives to T1 analyses makes operative inefficiencies hard to spot, SOC performance hard to measure (and therefore improve), results in overall lower security for the monitored environment(s), and contributes to analyst burnout. In this work we collaborate with a commercial SOC to devise a 4-stage (network) process to support the collection and analysis of relevant information for threat analysis. We conduct an experiment with ten T1 analysts employed in the SOC and show that analysts following the proposed process are 2.5 times more likely to produce an accurate assessment than analysts who do not. We evaluate qualitatively the effects of the process on analysts decisions, and discuss implications for practice and research
'Give Me Structure':Synthesis and Evaluation of a (Network) Threat Analysis Process Supporting Tier 1 Investigations in a Security Operation Center
Proposed roles of the immune response regulator-ThPOK in human colorectal cancer progression
Solid tumours are commonly infiltrated by several immune cells [1-3]. In cancer, immune cells play conflicting roles with both the potentials to eliminate or to promote malignancy. In contrast to infiltration of cells responsible for chronic inflammation, the presence of high numbers of lymphocytes, especially T cells, has been reported to be important as indicator of good prognosis in many types of cancer [4-7]. The thorough knowledge of both manners and pathways with which tumors are able to evade immune-mediated attack, once established, is therefore of crucial importance. The strategies to escape anti-tumor immune responses include the limited priming or differentiation of antitumor T cells and the role of tumor microenvironment in order to prevent infiltration or activation of effector phase functions.
We proposed to evaluate the role of Th inducing POZ-Kruppel Factor (ThPOK), a transcriptional regulator of T cell fate, in tumour-induced immune system plasticity during colorectal carcinogenesis. Data were collected on the amounts of CD4+, CD8+ and CD56+ as well as on ThPOK+ cells infiltrated in normal colorectal mucosa (NM), in dysplastic aberrant crypt foci (microadenomas, MA, the earliest detectable lesions in colorectal carcinogenesis) and in colorectal carcinomas (CRC); moreover, the colocalization of ThPOK with the above-mentioned markers of immune cells was evaluated using confocal microscopy. Interestingly, ThPOK showed a prominent increase since MA. A strong colocalization of ThPOK with CD4 both in NM and in MA was observed, weaker in carcinomas. Surprisingly, there was a peak in the colocalization levels of ThPOK with CD8 in MA, which was evident, although to a lesser extent, also in carcinomas. In conclusion, according to the data of the present study, ThPOK may be considered a central regulator of the earliest events in the immune system during colorectal cancer development.
The novelty of the present study is the proposed role of ThPOK in influencing the immune response against cancer cells.
References
[1] Dunn et al. (2004) The immunobiology of cancer immunosurveillance and immunoediting. Immunity 21: 137-148.
[2] Knaapen et al. (2006) Neutrophils and respiratory tract DNA damage and mutagenesis: a review. Muta-genesis 21: 225-236.
[3] Coussens and Werb (2002) Inflammation and cancer. Nature 420: 860-867.
[4] Watt and House (1978) Colonic carcinoma: a quantitative assessment of lymphocyte infiltration at the periphery of colonic tumors related to prognosis. Cancer 41: 279-282.
[5] Galon et al. (2006) Type, density, and location of immune cells within human colorectal tumors predict clinical outcome. Science 313: 1960-1964.
[6] Pagès et al. (2009) In situ cytotoxic and memory T cells predict outcome in patients with early-stage colorectal cancer. J Clin Oncol 27: 5944-5951.
[7] Mlecnik et al. (2010) Biomolecular network reconstruction identifies T-cell homing factors associated with survival in colorectal. Gastroenterology 138: 1429-1434
Attenuated polyposis of the large bowel: a morphologic and molecular approach
Attenuated polyposis could be defined as a variant of familial adenomatous polyposis (FAP) in which synchronous polyps of the large bowel range between 10 and 99. We analysed all cases of attenuated polyposis observed over the last 30 years with the objectives: (A) to classify the disease according to different type and proportion of polyps; (B) To ascertain the contribution of APC and MutYH genes; (C) to discover features which could arise the suspicion of mutations; (D) To obtain indications for management and follow-up. 84 individuals in 82 families were studied. Polyps were classified into four groups as adenoma, hyperplastic, other serrated lesions or others; APC and MutYH mutations were assessed. Mean age at diagnosis was 54 ± 14 years in men and 48 ± 13 in women (P = 0.005). Polyps were more numerous in women (37 ± 26 vs 29 ± 22). Sixty % of patients underwent bowel resection, mainly for cancer; the remaining were managed through endoscopy. A total of 2586 polyps were detected at diagnostic endoscopy: 2026 (80 %) were removed and analysed. Adenomas were diagnosed in 1445 (70 %), hyperplastic polyps in 541 (26 %), other serrated lesions in 61 (2.9 %). Adenomas and hyperplastic lesions were detected in the majority of patients. In 68 patients (81 %) in whom studies were executed, APC mutations were found in 8 and MutYH mutations in 10. Genetic variants were more frequent in women (12 vs 6, P = 0.039). Taking into consideration the prevalent (>50 %) histology and presence of mutations, patients could be subdivided into four groups: (1) APC mutated polyposis (AFAP), when adenomas were >50 % and APC mutations detected (no. 8, 10 %); (2) MutYH mutated polyposis (MAP), adenomas >50 % and biallelic MutYH mutations (no. 10, 12 %); (1) attenuated polyposis without detectable mutations, prevalence of adenomas, 48 cases (57 %); (1) hyperplastic-serrated polyposis, with prevalence (>50 %) of hyperplastic/other serrated lesions and no constitutional mutation (no. 18, 21 %). Aggregation of tumors, cancer in probands, distribution of polyps and other clinical characteristics showed no difference among the four groups. In conclusions, AFAP and MAP, the polyposis labeled by constitutional mutations, represented about 25 % of all attenuated polyposis. Mutation-associated cases showed an earlier age of onset of polyps and were more frequent in the female sex
PLZF expression during colorectal cancer development and in normal colorectal mucosa according to body size, as marker of colorectal cancer risk.
Promyelocytic leukemia zinc finger protein (PLZF) is a protein involved in various signaling, growth regulatory, and differentiation pathways, including development/function of some T cells. Here, we aimed at the detection of PLZF during colorectal carcinogenesis, using immunofluorescence, and at the evaluation of the colocalization of PLZF with CD2 and CD56 positive cells (T, \u3b3\u3b4, NK, and NKT cells), using confocal-microscopy, along colorectal carcinogenesis, since its earliest stages, that is, dysplastic aberrant crypt foci (ACF). Furthermore, we analyzed PLZF in the normal colonic mucosa (NM) according to anthropometric parameters of the subject. NM exhibited strong CD56 fluorescent staining. This infiltration was lost in both ACF and colorectal carcinoma (CRC), while PLZF presence increased from NM to ACF and CRC. Strong association was found between CD56+ colonic mucosa cell infiltration and body mass index. Interestingly, an increased stromal PLZF-reactivity was present in NM of obese subjects. This study shows that overexpression of PLZF and exclusion of NK cells in dysplastic microenvironment are very early events in the stepwise sequence leading to CRC and that lower levels of CD56+ cells in NM, together with increased levels of PLZF+ cells, can be a reflection of colon cancer risk due to obesity
Matrix metalloproteinases 15 and 19 are stromal regulators of colorectal cancer development from the early stages
Matrix metalloproteinases (MMPs) have been well characterized for their ability to degrade extracellular matrix proteins and, thus, they have been studied to elucidate their involvement in both tumor development and progression. In the present study, attention was focused on MMP-15 and MMP-19, two less known members of the MMP family. The expression profile of MMP-15 and -19 was assayed in samples of normal colorectal mucosa, microadenomas and cancer using confocal analysis, western blotting and quantitative reverse transcription polymerase chain reaction (qRT-PCR). Both qRT-PCR and western blotting showed that MMP-15 and MMP-19 appeared to be upregulated during colorectal tumorigenesis, with different expression patterns: MMP-15 expression level increases from normal mucosa to microadenomas, with a reduced level in cancer with respect to microadenomas; the semiquantitative immunofluorescence analysis showed a stromal localization of this protein in the early phases of neoplastic transformation. Increasing amount of MMP-19 mRNA and protein levels were observed in the progression of colonic lesions; MMP-19 staining increased in the normal mucosa-microadenoma-carcinoma sequence. Such different expression patterns, are probably due to the different roles played in colorectal tumorigenesis by these two molecules. Conflicting data on the role of these proteins in tumor progression have been reported, thus, an improved understandingof the biological roles of MMPs, in particular the lesser known members such as MMP-15 and 19, in colorectal cancer may lead to a re-evaluation of the use of MMP inhibitors and suggests the need of integrated translational studies on MMP expression patterns
- …