Faith and Fate: Limits of Transformers on Compositionality

Transformer large language models (LLMs) have sparked admiration for their exceptional performance on tasks that demand intricate multi-step reasoning. Yet, these models simultaneously show failures on surprisingly trivial problems. This begs the question: Are these errors incidental, or do they signal more substantial limitations? In an attempt to demystify Transformers, we investigate the limits of these models across three representative compositional tasks -- multi-digit multiplication, logic grid puzzles, and a classic dynamic programming problem. These tasks require breaking problems down into sub-steps and synthesizing these steps into a precise answer. We formulate compositional tasks as computation graphs to systematically quantify the level of complexity, and break down reasoning steps into intermediate sub-procedures. Our empirical findings suggest that Transformers solve compositional tasks by reducing multi-step compositional reasoning into linearized subgraph matching, without necessarily developing systematic problem-solving skills. To round off our empirical study, we provide theoretical arguments on abstract multi-step reasoning problems that highlight how Transformers' performance will rapidly decay with increased task complexity.Comment: 10 pages + appendix (21 pages

Enzymes immobilized in Langmuir-Blodgett films: Why determining the surface properties in Langmuir monolayer is important?

ABSTRACT In this review we discuss about the immobilization of enzymes in Langmuir-Blodgett films in order to determine the catalytic properties of these biomacromolecules when adsorbed on solid supports. Usually, the conformation of enzymes depends on the environmental conditions imposed to them, including the chemical composition of the matrix, and the morphology and thickness of the film. In this review, we show an outline of manuscripts that report the immobilization of enzymes as LB films since the 1980’s, and also some examples of how the surface properties of the floating monolayer prepared previously to the transfer to the solid support are important to determine the efficiency of the resulting device

Performance Analysis in the Downlink of Asynchronous OFDM/FBMC Based Multi-Cellular Networks

International audienc

ATOM, the all-inclusive, nominal EAES classification of bile duct injuries during cholecystectomy

Several studies seem to indicate at least a 2-fold increase in bile duct injuries (BDI) since the inception of laparoscopic cholecystectomy. Moreover, injuries seem to be more proximal, seem to be revealed earlier, are expressed by leaks more often than by strictures, are repaired more frequently by nonspecialists (either during the index operation or soon after), and appear to be more often associated with loss of substance and ischemia. The plethora of prior classifications probably attests to the evolving clinical spectrum, the mounting wealth of ever-increasing diagnostic methods, and an acknowledgment of insufficiencies or lack of data in earlier classification reports. Previous attempts at uniformity remain incomplete. The purpose of this study was to devise a nominal classification, combining all existing classification items, taking into account the changing pattern of BDI. Extensive bibliographic research, analysis of each category within the individual classifications combined into one uniform classification. Fifteen classifications were retained. All items were integrated into the European Association for Endoscopic Surgery (EAES) classification, using semantic connotations, grouped in three easy-to-remember categories, A (for anatomy), To (for time of), M (for mechanism): (1) the anatomic characteristics of the injury: NMBD for non-main bile duct or MBD for main bile duct (followed by a number 1-6, corresponding to the anatomic level on the MBD), followed by Oc (for occlusion) or D (division), P (partial) or C (complete), LS (loss of substance), VBI (vasculobiliary injury in general), and whenever known, the vessel; (2) time of detection: Ei (early intraoperative), Ep (early postoperative) or L (late); and (3) mechanism of injury: Me (mechanical) or ED (energy-driven). The EAES composite, all-inclusive, nominal classification ATOM (anatomic, time of detection, mechanism) should allow combination of all information on BDI, irrespective of the original classification used, and thus facilitate epidemiologic and comparative studies; indicate simple, appropriate preventive measures; and better guide therapeutic indications for iatrogenic BDI occurring during cholecystectom

ATOM, the all-inclusive, nominal EAES classification of bile duct injuries during cholecystectomy.

Abstract BACKGROUND: Several studies seem to indicate at least a 2-fold increase in bile duct injuries (BDI) since the inception of laparoscopic cholecystectomy. Moreover, injuries seem to be more proximal, seem to be revealed earlier, are expressed by leaks more often than by strictures, are repaired more frequently by nonspecialists (either during the index operation or soon after), and appear to be more often associated with loss of substance and ischemia. The plethora of prior classifications probably attests to the evolving clinical spectrum, the mounting wealth of ever-increasing diagnostic methods, and an acknowledgment of insufficiencies or lack of data in earlier classification reports. Previous attempts at uniformity remain incomplete. The purpose of this study was to devise a nominal classification, combining all existing classification items, taking into account the changing pattern of BDI. METHODS: Extensive bibliographic research, analysis of each category within the individual classifications combined into one uniform classification. RESULTS: Fifteen classifications were retained. All items were integrated into the European Association for Endoscopic Surgery (EAES) classification, using semantic connotations, grouped in three easy-to-remember categories, A (for anatomy), To (for time of), M (for mechanism): (1) the anatomic characteristics of the injury: NMBD for non-main bile duct or MBD for main bile duct (followed by a number 1-6, corresponding to the anatomic level on the MBD), followed by Oc (for occlusion) or D (division), P (partial) or C (complete), LS (loss of substance), VBI (vasculobiliary injury in general), and whenever known, the vessel; (2) time of detection: Ei (early intraoperative), Ep (early postoperative) or L (late); and (3) mechanism of injury: Me (mechanical) or ED (energy-driven). CONCLUSIONS: The EAES composite, all-inclusive, nominal classification ATOM (anatomic, time of detection, mechanism) should allow combination of all information on BDI, irrespective of the original classification used, and thus facilitate epidemiologic and comparative studies; indicate simple, appropriate preventive measures; and better guide therapeutic indications for iatrogenic BDI occurring during cholecystectomy.Abstract BACKGROUND: Several studies seem to indicate at least a 2-fold increase in bile duct injuries (BDI) since the inception of laparoscopic cholecystectomy. Moreover, injuries seem to be more proximal, seem to be revealed earlier, are expressed by leaks more often than by strictures, are repaired more frequently by nonspecialists (either during the index operation or soon after), and appear to be more often associated with loss of substance and ischemia. The plethora of prior classifications probably attests to the evolving clinical spectrum, the mounting wealth of ever-increasing diagnostic methods, and an acknowledgment of insufficiencies or lack of data in earlier classification reports. Previous attempts at uniformity remain incomplete. The purpose of this study was to devise a nominal classification, combining all existing classification items, taking into account the changing pattern of BDI. METHODS: Extensive bibliographic research, analysis of each category within the ind

ATOM, the all-inclusive, nominal EAES classification of bile duct injuries during cholecystectomy

Several studies seem to indicate at least a 2-fold increase in bile duct injuries (BDI) since the inception of laparoscopic cholecystectomy. Moreover, injuries seem to be more proximal, seem to be revealed earlier, are expressed by leaks more often than by strictures, are repaired more frequently by nonspecialists (either during the index operation or soon after), and appear to be more often associated with loss of substance and ischemia. The plethora of prior classifications probably attests to the evolving clinical spectrum, the mounting wealth of ever-increasing diagnostic methods, and an acknowledgment of insufficiencies or lack of data in earlier classification reports. Previous attempts at uniformity remain incomplete. The purpose of this study was to devise a nominal classification, combining all existing classification items, taking into account the changing pattern of BDI. Extensive bibliographic research, analysis of each category within the individual classifications combined into one uniform classification. Fifteen classifications were retained. All items were integrated into the European Association for Endoscopic Surgery (EAES) classification, using semantic connotations, grouped in three easy-to-remember categories, A (for anatomy), To (for time of), M (for mechanism): (1) the anatomic characteristics of the injury: NMBD for non-main bile duct or MBD for main bile duct (followed by a number 1-6, corresponding to the anatomic level on the MBD), followed by Oc (for occlusion) or D (division), P (partial) or C (complete), LS (loss of substance), VBI (vasculobiliary injury in general), and whenever known, the vessel; (2) time of detection: Ei (early intraoperative), Ep (early postoperative) or L (late); and (3) mechanism of injury: Me (mechanical) or ED (energy-driven). The EAES composite, all-inclusive, nominal classification ATOM (anatomic, time of detection, mechanism) should allow combination of all information on BDI, irrespective of the original classification used, and thus facilitate epidemiologic and comparative studies; indicate simple, appropriate preventive measures; and better guide therapeutic indications for iatrogenic BDI occurring during cholecystectomy

Prevention and treatment of bile duct injuries during laparoscopic cholecystectomy: the clinical practice guidelines of the European Association for Endoscopic Surgery (EAES).

BACKGROUND: Laparoscopic cholecystectomy is one of the most common surgical procedures in Europe (and the world) and has become the standard procedure for the management of symptomatic cholelithiasis or acute cholecystitis in patients without specific contraindications. Bile duct injuries (BDI) are rare but serious complications that can occur during a laparoscopic cholecystectomy. Prevention and management of BDI has given rise to a host of publications but very few recommendations, especially in Europe. METHODS: A systematic research of the literature was performed. An international expert panel was invited to appraise the current literature and to develop evidence-based recommendations. Statements and recommendations were drafted after a consensus development conference in May 2011, followed by presentation and discussion at the annual congress of the EAES held in Torino in June 2011. Finally, full guidelines were consented and adopted by the expert panel via e-mail and web conference. RESULTS: A total of 1,765 publications were identified through the systematic literature search and additional submission by panellists; 671 publications were selected as potentially relevant. Only 46 publications fulfilled minimal methodological criteria to support Clinical Practice Guidelines recommendations. Because the level of evidence was low for most of the studies, most statements or recommendations had to be based on consensus of opinion among the panel members. A total of 15 statements and recommendations were developed covering the following topics: classification of injuries, epidemiology, prevention, diagnosis, and management of BDI. CONCLUSIONS: Because BDI is a rare event, it is difficult to generate evidence for prevention, diagnosis, or the management of BDI from clinical studies. Nevertheless, the panel has formulated recommendations. Due to the currently limited evidence, a European registry should be considered to collect and analyze more valid data on BDI upon which recommendations can be based.BACKGROUND: Laparoscopic cholecystectomy is one of the most common surgical procedures in Europe (and the world) and has become the standard procedure for the management of symptomatic cholelithiasis or acute cholecystitis in patients without specific contraindications. Bile duct injuries (BDI) are rare but serious complications that can occur during a laparoscopic cholecystectomy. Prevention and management of BDI has given rise to a host of publications but very few recommendations, especially in Europe. METHODS: A systematic research of the literature was performed. An international expert panel was invited to appraise the current literature and to develop evidence-based recommendations. Statements and recommendations were drafted after a consensus development conference in May 2011, followed by presentation and discussion at the annual congress of the EAES held in Torino in June 2011. Finally, full guidelines were consented and adopted by the expert panel via e-mail and web confere