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Reducing energy use and improving engine efficiency is a complex task however to date a continued reduction of lubricant viscosity has proved effective. Reducing viscosity decreases hydrodynamic friction and pumping losses however it can also exacerbate boundary friction losses. Detailed and representative component level experimentation is required to understand the effects of viscosity reduction on friction and opportunity for further optimisation. This paper presents a novel motored reciprocating Tribometer which has been developed to measure the friction between complete cylinder liners and three-piece oil control rings. The system holds individual or multiple rings stationary in a bespoke ring holder and reciprocate the cylinder liner thereby replicates the relative kinematics of the components in service. The new design has many operational advantages to identify and benchmark the individual contribution of oil control ring friction including near total isolation of oil ring-cylinder liner bore conjunction, pure rectilinear motion and use of full components without resorting to split liner/ring geometries. The experimental rig is used to measure friction at the three-piece oil control ring- cylinder liner conjunction when lubricated with two low viscosity lubricants. The results show prevalence of mixed regime lubrication across the speeds, temperatures and lubricants investigated. The oil control ring under investigation is shown to operate in mixed regime lubrication and at cold start the introduction of lower viscosity lubricants such as 0W-8 showed higher level of oil control ring-cylinder liner friction in comparison to the 0W-40. The information and experimental facility are of critical use for engine designers when considering the potential contradictory component efficiency behaviour when moving to ultra-low viscosity lubricants.

Since the beginning of the COVID-19 pandemic, several mutations of the SARS-CoV-2 virus have emerged. Current gold standard detection methods for detecting the virus and its variants are based on PCR-based diagnostics using complex laboratory protocols and time-consuming steps, such as RNA isolation and purification, and thermal cycling. These steps limit the translation of technology to the point-of-care and limit accessibility to under-resourced regions. While PCR-based assays currently offer the possibility of multiplexed gene detection, and commercial products of single gene PCR and isothermal LAMP at point-of-care are also now available, reports of isothermal assays at the point-of-care with detection of multiple genes are lacking. Here, we present a microfluidic assay and device to detect and differentiate the Alpha variant (B.1.1.7) from the SARS-CoV-2 virus early strains in saliva samples. The detection assay, which is based on isothermal RT-LAMP amplification, takes advantage of the S-gene target failure (SGTF) to differentiate the Alpha variant from the SARS-CoV-2 virus early strains using a binary detection system based on spatial separation of the primers specific to the N- and S-genes. We use additively manufactured plastic cartridges in a low-cost optical reader system to successfully detect the SARS-CoV-2 virus from saliva samples (positive amplification is detected with concentration ≥10 copies per μL) within 30 min. We demonstrate that our platform can discriminate the B.1.1.7 variant (USA/CA_CDC_5574/2020 isolate) from SARS-CoV-2 negative samples, but also from the SARS-CoV-2 USA-WA1/2020 isolate. The reliability of the developed point-of-care device was confirmed by testing 38 clinical saliva samples, including 20 samples positive for Alpha variant (sensitivity90%, specificity = 100%). This study highlights the current relevance of binary-based testing, as the new Omicron variant also exhibits S-gene target failure and could be tested by adapting the approach presented here.

Background: Despite advances in surgical techniques, the use of maximal repair to treat large or massive rotator cuff tears results in a high retear rate postoperatively. Currently, no randomized controlled trials have compared the outcomes of maximal repair with interposition dermal allograft bridging reconstruction. Hypothesis: We hypothesized that large or massive rotator cuff tendon tears reconstructed using bridging dermal allograft would have better clinical outcomes 2 years postoperatively, as measured using the Western Ontario Rotator Cuff (WORC) index, than would those receiving the current gold standard treatment of debridement and maximal repair alone. We also expected that patients treated via bridging reconstruction using dermal allograft would have fewer postoperative failures as assessed using postoperative magnetic resonance imaging scans. Study Design: Randomized controlled trial; Level of evidence 1. Methods: A sample size of 30 patients (determined using a priori sample size calculation) with massive, retracted rotator cuff tears were randomly allocated to 1 of 2 groups: maximal repair or bridging reconstruction using dermal allograft. All patients completed questionnaires (WORC and Disabilities of the Arm, Shoulder and Hand [DASH]) preoperatively and postoperatively at 3 months, 6 months, 1 year, and 2 years. The primary outcome of this study was the WORC index at 2 years. Secondary outcomes included healing rate, progression of rotator cuff arthropathy, and postoperative acromiohumeral distance in both groups. Results: Patients treated via bridging reconstruction using dermal allograft had better postoperative WORC and DASH scores (23.93 ± 24.55 and 15.77 ± 19.27, respectively) compared with patients who received maximal repair alone (53.36 ± 31.93 and 34.32 ± 23.31, respectively). We also noted increased progression to rotator cuff arthropathy in the maximal repair group with an increased retear rate when compared with the reconstruction group (87% and 21%, respectively; P < .001). The acromiohumeral distance was maintained in the reconstruction group but significantly decreased in the maximal repair group. Conclusion: Rotator cuff bridging reconstruction using a dermal allograft demonstrated improved patient-reported outcomes as measured using the WORC index 2 years postoperatively. This technique also showed favorable structural healing rates and decreased progression to arthropathy compared with maximal repair. Trial Registration: ClinicalTrials.gov (NCT01987973)

The Maryland Department of Natural Resources and the Maryland Offshore Wind Development Fund at the Maryland Energy Administration cosponsored this work. This report was prepared as an account of work sponsored by an agency of the United States Government. There is strong socio-political support for offshore wind development in US territorial waters and construction is planned off several east coast states. Some of the planned development sites coincide with important habitat for critically endangered North Atlantic right whales. Both exclusion zones and passive acoustic monitoring are important tools for managing interactions between marine mammals and human activities. Understanding where animals are with respect to exclusion zones is important to avoid costly construction delays while minimizing the potential for negative impacts. Impact piling from construction of hundreds of offshore wind turbines likely require exclusion zones as large as 10 km. We have developed a three-hydrophone passive acoustic monitoring system that provides bearing information along with marine mammal detections to allow for informed management decisions in real-time. Multiple units form a monitoring system designed to determine whether marine mammal calls originate from inside or outside of an exclusion zone. In October 2021, we undertook a full system validation, with a focus on evaluating the detection range and bearing accuracy of the system with respect to right whale upcalls. Five units were deployed in Mid-Atlantic waters and we played more than 3500 simulated right whale upcalls at known locations to characterize the detection function and bearing accuracy of each unit. The modelled results of the detection function error were then used to compare the effectiveness of a bearing-based system to a single sensor that can only detect a signal but not ascertain directivity. Field trials indicated maximum detection ranges from 4-7.3 km depending on source and ambient noise levels. Simulations showed that incorporating bearing detections provide a substantial improvement in false alarm rates (6 to 12 times depending on number of units, placement and signal to noise conditions) for a small increase in the risk of missed detections inside of an exclusion zone (1%-3%). We show that the system can be used for monitoring exclusion zones and clearly highlight the value of including bearing estimation into exclusion zone monitoring plans while noting that placement and configuration of units should reflect anticipated ambient noise conditions. Publisher PDF

The squirrel glider (Petaurus norfolcensis) is a threatened, gliding marsupial that persists in fragmented landscapes despite its restricted capacity to cross large gaps. As measures to maintain and/or restore suitable habitat depend on knowledge about the species' ecological requirements, we investigated the area used by squirrel gliders in an urban area near Newcastle, Australia. Using GPS telemetry data and the autocorrelated kernel density estimator, we estimated area used to average 10.8 ha and varied from 4.6 to 15 ha, which is equal to or greater than found in previous studies that spanned longer time periods. This has implications when identifying the minimum patch size necessary for ensuring the long‐term conservation of a squirrel glider population., We estimated the space use of squirrel gliders in an urban area using GPS telemetry. Area used varied from 5 to 15 ha which is in the upper range of previously reported. ​

A mild and direct strategy for the 1-alkylation of isochroman, isothiochroman and tetrahydroisoquinoline cores has been achieved through the combination of photoredox and nickel catalysis. The resulting motifs are commonly found in bioac-tive compounds and natural products, but accessibility has to date been limited to scaffolds containing electron-rich aro-matic rings. The approach reported here, using an easily syn-thesized carboxylic acid building block in a cross-coupling manifold, enables rapid access to diverse scaffolds with broad functional group tolerance on a gram scale.

Ampere Scientific’s VARmetric TM measurement system for Vacuum Arc Remelting (VAR) furnaces passively monitors the distribution of arcs over time during VAR in real time. The arc behavior is known to impact both product yield and quality and can pose potentially catastrophic operating conditions. Arc position sensing with VARmetric TM enables a new approach to control the heat input to the melt pool. Transverse external magnetic fields were applied to push the arcs via the Lorentz force while measuring the arc location to control the arc distribution over time. This has been tested on Ampere Scientific’s small-scale laboratory arc furnace with electromagnets used for control for up to 60 seconds while monitoring the arc location with VARmetric TM. The arc distributions were shown to be significantly different from the uncontrolled distributions with distinct thermal profiles at the melt pool. Alternatively, this type of control can be periodically applied to react to undesirable arc conditions.

To evaluate the effectiveness of celecoxib, a selective cyclooxygenase 2 inhibitor, in reducing heterotopic ossification (HO) after hip arthroscopic surgery and to evaluate celecoxib's impact on clinical outcomes.We performed a retrospective review of patients who received hip arthroscopy performed by the same surgeon between January 1, 2012, and December 31, 2016. Patients who had an allergy to sulfa drugs, had pre-existing HO or previous surgery on the operative side, or failed to complete radiographic follow-up at 6 months postoperatively were excluded. Patients in the treatment group received 400 mg of celecoxib postoperatively for 6 weeks, whereas the control group received no postoperative celecoxib. The incidence of HO was assessed using anteroposterior radiographs obtained at 6 months, 1 year, and 2 years postoperatively. Patients completed the International Hip Outcome Tool 33 survey, and the proportion of patients who met the minimal clinically important difference, substantial clinical benefit (SCB), and absolute SCB was calculated.A total of 559 patients were identified. After application of the exclusion criteria, 454 patients were included in the study (211 in control group and 243 in treatment group). The overall incidence of HO was 20.3% (n = 92). The treatment group had a significantly lower incidence of HO at 6 months (P = .006), 1 year (P.001), and 2 years (P = .008) postoperatively. At 2 years postoperatively, the treatment group had a significantly higher International Hip Outcome Tool 33 score on average: 64.2 versus 57.3 (P = .023). No significant difference in the proportion of patients reaching the minimal clinically important difference, SCB, or absolute SCB was found at any of the postoperative time points.The findings of this study suggest that a prophylactic treatment regimen of 400 mg of celecoxib once daily for 6 weeks significantly reduces the incidence of HO formation after hip arthroscopic surgery; however, it did not impact clinical outcomes.Level III, retrospective, comparative case-control study.

Introduction. Hip replacement is a frequently performed and highly successful treatment for patients with end stage osteoarthritis. Advances in technique and pain management have allowed for rapid mobilization and early discharge after surgery. We hypothesize that pre-incision intra-articular injection of local anesthetic with epinephrine under image guidance combined with post incision peri-articular injection (PAI) may be more effective than PAI alone. Methods. A prospective, randomized, controlled, comparative investigation at a single institution of 41 patients undergoing THA who received standard 30 mL post-arthrotomy, PAI of ropivacaine with epinephrine under direct visualization after prosthesis implantation before closure or an equivalent dose divided into a 10 mL pre-incision, ultrasound guided intra-articular injection and a 20 mL post-arthrotomy PAI. Results. 42 patients were included in this study before its early conclusion with 22 patients in the treatment group and 20 in the control group. There were no significant differences in age, BMI or ASA scores. Additionally, there were no significant differences noted when comparing groups by postoperative outcome measures including OMME, EBL, OR time, PACU minutes, and first and last PACU pain score. Furthermore, there were no significant differences in the PROMs evaluated. Discussion. The addition of ultrasound guided pre-incision intra-articular injection to the standard PAI had no benefit when compared with standard PAI during a THA. Portable mobile phone based ultrasound devices provide a cost effective way to perform musculoskeletal blocks, and further studies on their use and comparative accuracy is warranted. A novel technique for confirmation of injection location is described.

In this study, we aimed to evaluate the medium-term clinical outcomes for patients who underwent bridging reconstruction.A retrospective chart review was conducted for all patients who underwent bridging reconstruction between 2010 and 2018. Patients who were missing either pre- or postoperative outcome scores were excluded. All included patients completed self-reported questionnaires (Western Ontario Rotator Cuff [WORC] and Disabilities of the Arm, Shoulder and Hand [DASH]) pre- and postoperatively at 6 months, 1 year, and annually thereafter. All scores were reported out of 100.Ninety-one patients initially met our inclusion criteria, and 33 were excluded owing to lack of either pre- or postoperative outcome scores. Nine patients were lost to follow-up; therefore, 49 patients were finally evaluated, including 30 males (61.2%) and 19 females (38.8%) with an age of 59.6 ± 10.4 years (mean ± standard deviation) and mean follow-up of 5.3 years (range 2 to 9). Both WORC and DASH scores significantly improved from pre- to postoperatively (WORC: 69.6 ± 12.2 to 27.9 ± 23.7, P.001; DASH: 51.5 ± 17.5 to 24.5 ± 23.0, P = .001). For WORC and DASH, 92% and 74% of patients, respectively, met the minimal clinical importance difference.Our results showed that patients' clinical outcome scores significantly improved with an average of 5-year follow-up, which demonstrates that bridging reconstruction is a safe procedure with promising midterm clinical outcomes.IV, retrospective case series.