Threshold Limit Value for biomechanical risk factors (ACGIH-TLV®): a cohort study on carpal tunnel syndrome in manual workers

OBIETTIVI: Per esplorare il contributo dei fattori di rischio biomeccanico, ripetitività (hand activity level – HAL) e forza manuale (peak force - PF), nell’insorgenza della sindrome del tunnel carpale (STC), abbiamo studiato un’ampia coorte di lavoratori dell’industria, utilizzando come riferimento il valore limite di soglia (TLV©) dell’American Conference of Governmental Industrial Hygienists (ACGIH). METODI: La coorte è stata osservata dal 2000 al 2011. Abbiamo classificato l’esposizione professionale rispetto al limite di azione (AL) e al TLV dell’ACGIH in: “accettabile” (sotto AL), “intermedia” (tra AL e TLV) e “inaccettabile” (sopra TLV). Abbiamo considerato due definizioni di caso: 1) sintomi di STC; 2) sintomi e positività allo studio di conduzione nervosa (SCN). Abbiamo applicato modelli di regressione di Poisson aggiustati per sesso, età, indice di massa corporea e presenza di patologie predisponenti la malattia. RISULTATI: Nell’intera coorte (1710 lavoratori) abbiamo trovato un tasso di incidenza (IR) di sintomi di STC di 4.1 per 100 anni-persona; un IR di STC confermata dallo SCN di 1.3 per 100 anni-persona. Gli esposti “sopra TLV” presentano un rischio di sviluppare sintomi di STC di 1.76 rispetto agli esposti “sotto AL”. Un andamento simile è emerso per la seconda definizione di caso [incidence rate ratios (IRR) “sopra TLV”, 1.37 (intervallo di confidenza al 95% (IC95%) 0.84–2.23)]. Gli esposti a “carico intermedio” risultano a maggior rischio per la STC [IRR per i sintomi, 3.31 (IC95% 2.39–4.59); IRR per sintomi e SCN positivo, 2.56 (IC95% 1.47–4.43)]. Abbiamo osservato una maggior forza di associazione tra HAL e la STC. CONCLUSIONI: Abbiamo trovato un aumento di rischio di sviluppare la STC all’aumentare del carico biomeccanico: l’aumento di rischio osservato già per gli esposti a “carico intermedio” suggerisce che gli attuali valori limite potrebbero non essere sufficientemente protettivi per alcuni lavoratori. Interventi di prevenzione vanno orientati verso attività manuali ripetitive.OBJECTIVES: To explore the role of workplace physical factors, particularly repetition (hand activity level – HAL) and manual force (normalized peak force – PF), in the development of carpal tunnel syndrome (CTS), we studied a large cohort of industrial workers with reference to a threshold limit value (TLV©) proposed by the American Conference of Governmental Industrial Hygienists (ACGIH). METHODS: Industrial workers were followed from 2000-2011. We classified subjects with respect to action limit (AL) and TLV. Case definitions were: (i) self-reported symptoms; and (ii) a combination of symptoms and positive nerve conduction studies (NCS). Poisson regression models including age, gender, body mass index, and presence of predisposing pathologies were conducted to estimate incidence rate ratios (IRR) of CTS. RESULTS: There were 1710 subjects with complete information at baseline and with at least one follow-up. We found an incidence rate (IR) of 4.1 per 100 person-years for CTS symptoms, and an IR of 1.3 per 100 person-years for CTS confirmed by NCS. “Unacceptable overload” (above TLV) was associated with a 1.76-fold risk of CTS symptoms, as compared with “acceptable load” (below the AL). A similar trend also emerged for CTS confirmed by NCS, but was not significant [IRR above TLV, 1.37 (95% confidence interval ( 95% CI) 0.84–2.23)]. Workers exposed between AL and TLV appeared at higher risk for CTS [IRR for symptoms, 3.31 (95% CI 2.39–4.59); IRR for symptoms and positive NCS, 2.56 (95% CI 1.47–4.43)]. HAL was a strong predictor of the outcome variables. CONCLUSIONS: Workplace risk factors contribute to the risk for CTS. Our study shows an increased risk for workers exposed between AL and TLV, suggesting that the current limits might not be sufficiently protective for some workers. Preventive efforts should target repetitive movements

Knee osteoarthritis in a chestnut farmer – Case Report

Introduction Several studies have dealt with the issue of professional risk factors and onset of knee osteoarthritis (OA). In particular, occupational epidemiological studies have provided evidence that activities resulting in biomechanical overload may be linked with an increased risk of knee OA – also among farmers. To our knowledge, no cases of knee OA among chestnut farmers have been reported in the literature. Case report We report the case of a 70-year-old Caucasian male who has worked for more than 50 years on a chestnut farm. In 2007, an X-ray and a MRI, performed after a workplace accident to his left knee, showed the presence of knee OA. His job required a range of repetitive tasks, such as squatting, kneeling, climbing, walking on sloping terrain, assuming uncomfortable postures, and lifting and carrying heavy loads for the great majority of the working day. All the aforementioned tasks are known occupational risk factors for knee OA. Regarding individual risk factors, at the time of the first diagnosis of knee OA, the worker was 64-years-old with a body mass index of 26.5 kg/m2. He reported no cases of arthritis among his relatives and no sports playing on his part. In addition, his medical history revealed the presence of two minor lumbar disc herniations and tendinitis of the long head of the biceps. Conclusions Considering the lack of major individual risk factors for knee OA, it is reasonable to suppose that five decades of exposure to biomechanical overload as a chestnut farmer was a relevant risk factor for the onset of the disease

Magnetoresistance and energy model of Alq3-based spintronic devices

Spin transport in organic semiconductors has been receiving widespread attention since the first experimental demonstration of magnetoresistive effects (change in resistance under an applied magnetic field) in hybrid ferromagnetic/organic/ferromagnetic structures [1]. Continuous effort in the field has led to the realization, for example, of vertical organic spintronic devices with differ- ent organic semiconductor layers [2,3] or organic tunnel barriers [4]. However, there is still a lack of understanding on the mechanism that governs spin injection and transport in organics, leading to general disagreement even on the expected sign of the devices output magnetoresistance. With the aim to clarify the spin transport behaviour in organic semiconductors, we present new results on hybrid inorganic/organic spin valves with the most successful up-to-date combination of materials [2-6]. The highly spin polarized manganite La2/3Sr1/3MnO3 and Cobalt have been used as ferromagnetic electrodes for spin injection into thick layers (up to 200 nm) of tris(8-hydrox- yquinoline)aluminum(III) (Alq3). In a critical design improvement, we have for the first time intro- duced an artificial tunnel barrier (Al2O3 or LiF) between the organic and the Co top electrode to study its influence on spin injection into organic semiconductors and to improve the chemical sta- bility and reproducibility of the devices. In our manuscript we: explore the importance of artificial tunnel barriers for spin injection in organics, record room temperature magnetoresistance, demonstrate that only ferromagnetic elec- trodes and not organic semiconductor limit device output and, finally, sketch an energy diagram able to explain negative magnetoresistance in LSMO/Alq3/Co spin valves. Our work is a new step forward in organic spintronics, as we prove that organic semiconductors do not have a clear limit for room temperature performance with the adequate ferromagnets, and we present a reliable model that could be easily extrapolated to predict the output of different materi- als combinations in hybrid spin valves. [1] Dediu, V., Murgia, M., Matacotta, F.C., Taliani, C. & Barbanera, S. Sol. State Commun. 122, 181-184 (2002). [2] Xiong, Z.H., Wu, D., Vardeny, Z.V. & Shi, J. Nature 427, 821-824 (2004). [3] Majumdar, S., Majumdar, H.S., Laiho, R. & Osterbacka, R. J. Alloy & Compounds 423, 169-171 (2006). [4] Santos, T.S., Lee, J.S., Migdal, P., Lekshmi, I.C., Satpati, B. & Moodera, J.S. Phys. Rev. Lett. 98, 016601 (2007). [5] Xu, W., Szulczewski, G.J., LeClair, P., Navarrete, I., Schad, R., Miao, G., Guo, H. & Gupta, A. Appl. Phys. Lett. 90, 072506 (2007). [6] Hueso, L.E., Riminucci, A., Bergenti, I., Zhan, Y. & Dediu, V. Adv. Mater. 19, 2639-2642 (2007)

Roadmap on thermoelectricity

The increasing energy demand and the ever more pressing need for clean technologies of energy conversion pose one of the most urgent and complicated issues of our age. Thermoelectricity, namely the direct conversion of waste heat into electricity, is a promising technique based on a long-standing physical phenomenon, which still has not fully developed its potential, mainly due to the low efficiency of the process. In order to improve the thermoelectric performance, a huge effort is being made by physicists, materials scientists and engineers, with the primary aims of better understanding the fundamental issues ruling the improvement of the thermoelectric figure of merit, and finally building the most efficient thermoelectric devices. In this Roadmap an overview is given about the most recent experimental and computational results obtained within the Italian research community on the optimization of composition and morphology of some thermoelectric materials, as well as on the design of thermoelectric and hybrid thermoelectric/photovoltaic devices

A case report of vibration-induced hand comorbidities in a postwoman

<p>Abstract</p> <p>Background</p> <p>Prolonged exposure to hand-transmitted vibration is associated with an increased occurrence of symptoms and signs of disorders in the vascular, neurological and osteoarticular systems of the upper limbs. However, the available epidemiological evidence is derived from studies on high vibration levels caused by vibratory tools, whereas little is known about possible upper limb disorders caused by chronic exposure to low vibration levels emitted by fixed sources.</p> <p>Case presentation</p> <p>We present the case of a postwoman who delivered mail for 15 years using a low-powered motorcycle. The woman was in good health until 2002, when she was diagnosed with bilateral Raynaud's phenomenon. In March 2003 a bilateral carpal tunnel syndrome was electromyographically diagnosed; surgical treatment was ineffective. Further examinations in 2005 highlighted the presence of chronic tendonitis (right middle finger flexor).</p> <p>Risk assessment</p> <p>From 1987, for 15 years, our patient rode her motorcycle for 4 h/day, carrying a load of 20-30 kg. For about a quarter of the time she drove over country roads. Using the information collected about the tasks carried out every day by the postwoman and some measurements performed on both handles of the motorcycle, as well as on both iron parts of the handlebars, we reconstructed the woman's previous exposure to hand-arm vibration. 8-hour energy-equivalent frequency weighted acceleration was about 2.4 m/s². The lifetime dose was 1.5 × 10⁹(m²/s⁴)hd.</p> <p>Conclusions</p> <p>The particular set of comorbidities presented by our patient suggests a common pathophysiological basis for all the diseases. Considering the level of exposure to vibrations and the lack of specific knowledge on the effects of vibration in women, we hypothesize an association between the work exposure and the onset of the diseases.</p

Segmental transverse colectomy. Minimally invasive versus open approach: results from a multicenter collaborative study

none65noThe role of minimally invasive surgery in the treatment of transverse colon cancer is still controversial. The aim of this study is to investigate the advantages of a totally laparoscopic technique comparing open versus laparoscopic/robotic approach. Three hundred and eighty-eight patients with transverse colon cancer, treated with a segmental colon resection, were retrospectively analyzed. Demographic data, tumor stage, operative time, intraoperative complications, number of harvested lymph nodes and recovery outcomes were recorded. Recurrences and death were also evaluated during the follow-up. No differences were found between conventional and minimally invasive surgery, both for oncological long-term outcomes (recurrence rate p = 0.28; mortality p = 0.62) and postoperative complications (overall rate p = 0.43; anemia p = 0.78; nausea p = 0.68; infections p = 0.91; bleeding p = 0.62; anastomotic leak p = 0.55; ileus p = 0.75). Nevertheless, recovery outcomes showed statistically significant differences in favor of minimally invasive surgery in terms of time to first flatus (p = 0.001), tolerance to solid diet (p = 0.017), time to first mobilization (p = 0.001) and hospital stay (p = 0.004). Compared with laparoscopic approach, robotic surgery showed significantly better results for time to first flatus (p = 0.001), to first mobilization (p = 0.005) and tolerance to solid diet (p = 0.001). Finally, anastomosis evaluation confirmed the superiority of intracorporeal approach which showed significantly better results for time to first flatus (p = 0.001), to first mobilization (p = 0.003) and tolerance to solid diet (p = 0.001); moreover, we recorded a statistical difference in favor of intracorporeal approach for infection rate (p = 0.04), bleeding (p = 0.001) and anastomotic leak (p = 0.03). Minimally invasive approach is safe and effective as the conventional open surgery, with comparable oncological results but not negligible advantages in terms of recovery outcomes. Moreover, we demonstrated that robotic approach may be considered a valid option and an intracorporeal anastomosis should always be preferred.noneMilone, Marco; Degiuli, Maurizio; Velotti, Nunzio; Manigrasso, Michele; Vertaldi, Sara; D'Ugo, Domenico; De Palma, Giovanni Domenico; Dario Bruzzese, Giuseppe Servillo, Giuseppe De Simone, Katia Di Lauro, Silvia Sofia, Marco Ettore Allaix, Mario Morino, Rossella Reddavid, Carlo Alberto Ammirati, Stefano Scabini, Gabriele Anania, Cristina Bombardini, Andrea Barberis, Roberta Longhin, Andrea Belli, Francesco Bianco, Giampaolo Formisano, Giuseppe Giuliani, Paolo Pietro Bianchi, Davide Cavaliere, Leonardo Solaini, Claudio Coco, Gianluca Rizzo, Andrea Coratti, Raffaele De Luca, Michele Simone, Alberto Di Leo, Giovanni De Manzoni, Paola De Nardi, Ugo Elmore, Riccardo Rosati, Andrea Vignali, Paolo Delrio, Ugo Pace, Daniela Rega, Antonio Di Cataldo, Giovanni Li Destri, Annibale Donini, Luigina Graziosi, Andrea Fontana, Michela Mineccia, Sergio Gentilli, Manuela Monni, Mario Guerrieri, Monica Ortenzi, Francesca Pecchini, Micaela Piccoli, Italy. Corrado Pedrazzani, Giulia Turri, Sara Pollesel, Franco Roviello, Marco Rigamonti, Michele Zuolo, Mauro Santarelli, Federica Saraceno, Pierpaolo Sileri Giuseppe Sigismondo Sica, Luigi Siragusa Salvatore Pucciarelli, Matteo ZuinMilone, Marco; Degiuli, Maurizio; Velotti, Nunzio; Manigrasso, Michele; Vertaldi, Sara; D'Ugo, Domenico; De Palma, Giovanni Domenico; Dario Bruzzese, Giuseppe Servillo, Giuseppe De Simone, Katia Di Lauro, Silvia Sofia, Marco Ettore Allaix, Mario Morino, Rossella Reddavid, Carlo Alberto Ammirati, Stefano Scabini, Gabriele Anania, Cristina Bombardini, Andrea Barberis, Roberta Longhin, Andrea Belli, Francesco Bianco, Giampaolo Formisano, Giuseppe Giuliani, Paolo Pietro Bianchi, Davide Cavaliere, Leonardo Solaini, Claudio Coco, Gianluca Rizzo, Andrea Coratti, Raffaele De Luca, Michele Simone, Alberto Di Leo, Giovanni De Manzoni, Paola De Nardi, Ugo Elmore, Riccardo Rosati, Andrea Vignali, Paolo Delrio, Ugo Pace, Daniela Rega, Antonio Di Cataldo, Giovanni Li Destri, Annibale Donini, Luigina Graziosi, Andrea Fontana, Michela Mineccia, Sergio Gentilli, Manuela Monni, Mario Guerrieri, Monica Ortenzi, Francesca Pecchini, Micaela Piccoli, Italy. Corrado Pedrazzani, Giulia Turri, Sara Pollesel, Franco Roviello, Marco Rigamonti, Michele Zuolo, Mauro Santarelli, Federica Saraceno, Pierpaolo Sileri Giuseppe Sigismondo Sica, Luigi Siragusa Salvatore Pucciarelli, Matteo Zui

Bowel preparation for elective colorectal resection: multi-treatment machine learning analysis on 6241 cases from a prospective Italian cohort

background current evidence concerning bowel preparation before elective colorectal surgery is still controversial. this study aimed to compare the incidence of anastomotic leakage (AL), surgical site infections (SSIs), and overall morbidity (any adverse event, OM) after elective colorectal surgery using four different types of bowel preparation. methods a prospective database gathered among 78 Italian surgical centers in two prospective studies, including 6241 patients who underwent elective colorectal resection with anastomosis for malignant or benign disease, was re-analyzed through a multi-treatment machine-learning model considering no bowel preparation (NBP; No. = 3742; 60.0%) as the reference treatment arm, compared to oral antibiotics alone (oA; No. = 406; 6.5%), mechanical bowel preparation alone (MBP; No. = 1486; 23.8%), or in combination with oAB (MoABP; No. = 607; 9.7%). twenty covariates related to biometric data, surgical procedures, perioperative management, and hospital/center data potentially affecting outcomes were included and balanced into the model. the primary endpoints were AL, SSIs, and OM. all the results were reported as odds ratio (OR) with 95% confidence intervals (95% CI). results compared to NBP, MBP showed significantly higher AL risk (OR 1.82; 95% CI 1.23-2.71; p = .003) and OM risk (OR 1.38; 95% CI 1.10-1.72; p = .005), no significant differences for all the endpoints were recorded in the oA group, whereas MoABP showed a significantly reduced SSI risk (OR 0.45; 95% CI 0.25-0.79; p = .008). conclusions MoABP significantly reduced the SSI risk after elective colorectal surgery, therefore representing a valid alternative to NBP

Abdominal drainage after elective colorectal surgery: propensity score-matched retrospective analysis of an Italian cohort

background: In italy, surgeons continue to drain the abdominal cavity in more than 50 per cent of patients after colorectal resection. the aim of this study was to evaluate the impact of abdominal drain placement on early adverse events in patients undergoing elective colorectal surgery. methods: a database was retrospectively analysed through a 1:1 propensity score-matching model including 21 covariates. the primary endpoint was the postoperative duration of stay, and the secondary endpoints were surgical site infections, infectious morbidity rate defined as surgical site infections plus pulmonary infections plus urinary infections, anastomotic leakage, overall morbidity rate, major morbidity rate, reoperation and mortality rates. the results of multiple logistic regression analyses were presented as odds ratios (OR) and 95 per cent c.i. results: a total of 6157 patients were analysed to produce two well-balanced groups of 1802 patients: group (A), no abdominal drain(s) and group (B), abdominal drain(s). group a versus group B showed a significantly lower risk of postoperative duration of stay &gt;6 days (OR 0.60; 95 per cent c.i. 0.51-0.70; P &lt; 0.001). a mean postoperative duration of stay difference of 0.86 days was detected between groups. no difference was recorded between the two groups for all the other endpoints. conclusion: this study confirms that placement of abdominal drain(s) after elective colorectal surgery is associated with a non-clinically significant longer (0.86 days) postoperative duration of stay but has no impact on any other secondary outcomes, confirming that abdominal drains should not be used routinely in colorectal surgery

On the Factors Affecting Design Education Within a Multi-Disciplinary Class

Design education is a highly debated topic since decades, yet the focus on multi-disciplinary classes has gained a paramount importance due to the multi-disciplinary nature of today's global challenges. This paper contributes to the discussion through the description of the Design Methods and Processes course at Alta Scuola Politecnica, an original educational experience jointly developed by Politecnico di Milano and Politecnico di Torino with a highly selected number of MS students from Architecture, Industrial Design and all branches of Engineering. After positioning this discussion with respect to the relevant literature, the paper describes the educational model of this course and the reflections made after 5 years of implementation. Students show to catch the essence of the design workflow thanks to the educational path structured as a problem-analysis-and-solving process. However, dealing with multi-disciplinary task demands a careful composition of students' teams since it can positively/negatively affect the learning experience as well as students' motivations

Rischi da lavoro nella grande distribuzione

AIM: This work provides an overview of the spectrum of possible occupational risk factors in the retail grocery store/supermarket workplace. METHOD: Literature on this theme, obtained consulting PubMed database and Google Scholar, was checked. We also exjlore results from the National bInstitute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration (OSHA). RESULTs: Contacts with objects, use of dangerous equipment (cutter, food slicer) and falls to the same level (slips, trips and falls) are the mainly described workplace hazards. Exposure to chemical (flour dust, components of detergents or disinfectants, volatile organic compounds and contact with nickel) and physical agents (cold exposure, nonionizing radiation and whole bpdy vibration) are reported by many authors. Relations between biomechanical and ergonomic risk factors and musculoskeletal disorders represent the main subjects of study. Few studies are found about biological agents (particularly among butchers). Data regarding psychosocial risks factors in this setting are still limited. CONCLUSIONS: Musculoskeletal disorders continue to be the most recurrent health problem between the grocery store workers (particularly low back pain and carpal tunnel syndrome among cashiers). Many technical documents and international Srecommendations are present to prevent these kinds of disorders. Psychosocial risk factors and risk of workplace violence should deserve further investigation