Assessment of a Hydrogen-Fueled Heavy-Duty Yard Truck for Roll-On and Roll-Off Port Operations

The port-logistic industry has a significant impact on the urban environment nearby ports and on the surrounding coastal areas. This is due to the use of large auxiliary power systems on ships operating during port stays, as well as to the employment of a number of fossil fuel powered road vehicles required for port operations. The environmental impact related to the use of these vehicles is twofold: on one hand, they contribute directly to port emissions by fuel consumption; on the other hand, they require some of the ship auxiliary systems to operate intensively, such as the ventilation system, which must operate to remove the pollutants produced by the vehicle engines inside the ship. The pathway to achieve decarbonization and mitigation of energy use in ports involves therefore the adoption of alternative and cleaner technology solutions for the propulsion systems of such port vehicles. This paper presents the performance analysis of a hydrogen powered cargo-handling vehicle for roll-on and roll-off port operations in a real case scenario. The fuel cell/battery hybrid powertrain of the vehicle has been previously designed by the authors. On the base of real data acquired during an on-field measurement campaign, and by means of a validated numerical model of the vehicle dynamics, different mission profiles are defined, in terms of driving and duty cycles, in order to represent typical port operations. A rule-based energy management strategy is then used to estimate the energy and hydrogen consumptions required by the vehicle and to assess its suitability to accomplish the defined target port operations. Outputs from this study show the potential of the proposed solution to take the place, in a foreseeable future, of conventional Diesel-engine vehicles, today commonly used in port logistics, towards a zero-emission scenario

Medium- to long-term clinical and functional outcomes of isolated and combined subscapularis tears repaired arthroscopically

Introduction The purpose of this study was twofold. First, the efficacy of arthroscopic repair in patients with full thickness, isolated subscapularis tendon tears (I-STTs) or combined subscapularis tendon tears (C-STTs) involving the rotator cuff tendons was evaluated. Second, the outcomes between these two groups were compared. The influence of age and gender on the cohort clinical outcomes was also analysed. Our hypothesis was that satisfactory functional results could be obtained arthroscopically in both groups without any influence of age or gender. Material and methods Seventy-nine patients were enrolled: 15 with I-STTs and 64 with C-STTs. The clinical outcomes were assessed using Constant and Disabilities of the Arm, Shoulder and Hand (DASH) scores, Numeric Rating Scale (NRS) for pain and Visual Analogue Scale (VAS) for satisfaction. The subscapularis strength was assessed using a comparative dynamometric bear-hug test. Group outcomes were compared, including statistical analysis. Results For each group, there were no differences regarding the subscapularis strength of the operated and non-operated shoulders. A comparison of the post- with the pre-operative outcomes showed an increase in the Constant score and a decrease in the NRS. Comparing the two groups, we found no difference in strength of the operated and non-operated shoulders, but a significant difference in relation to pre-operative Constant score and pre-operative NRS. Age was negatively correlated with both pre-operative and post-operative Constant scores. No association was found between gender and the outcomes, although the DASH score was higher in women. Conclusions Arthroscopic repair of STTs provided functional restoration, pain relief and patient satisfaction in both groups. Age and gender did not affect the clinical outcomes achieved by arthroscopic STT repair

Do Synovial Inflammation and Meniscal Degeneration Impact Clinical Outcomes of Patients Undergoing Arthroscopic Partial Meniscectomy? A Histological Study

The menisci exert a prominent role in joint stabilization and in the distribution of mechanical loading. Meniscal damage is associated with increased risk of knee OA. The aim of this study was to characterize the synovial membrane and meniscal tissues in patients undergoing arthroscopic partial meniscectomy for meniscal tear and to evaluate association with clinical outcomes. A total of 109 patients were recruited. Demographic and clinical data were collected. Visual Analogic Scale (VAS) measuring pain and Knee injury and Osteoarthritis Outcome Score (KOOS) were recorded at baseline and at 2-years follow-up. Histological and immunohistochemical characterizations were performed on synovial membranes and meniscal tissues. More than half of the patients demonstrated synovial mononuclear cell infiltration and hyperplasia. Synovial fibrosis was present in most of the patients; marked vascularity and CD68 positivity were observed. Inflammation had an impact on both pain and knee symptoms. Patients with synovial inflammation had higher values of pre-operative VAS and inflammation. Higher pre-operative pain was observed in patients with meniscal MMP-13 production. In conclusion, multivariate analysis showed that synovial inflammation was associated with pre-operative total KOOS scores, knee symptoms, and pain. Moreover, meniscal MMP-13 expression was found to be associated with pre-operative pain in multivariate analysis. Thus, targeting inflammation of the synovial membrane and meniscus might reduce clinical symptoms and dysfunction at the time of surgery