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Metalworking fluids (MWFs) lubricate, reduce forces and surface finish, and remove heat and swarf from the cutting zone. Lubricity additives influence wear and forces by reducing friction and preventing seizure. Additives(mineral oil, phosphate ester (P-ester), and dialkyl pentasulphide) were assessed for their machinability performance during Ti 6-4 milling with tungsten carbide(WC) endmills to establish life and cutting force coefficients (CFCs).P-ester additive provided the best performance;dialkyl pentasulphide(DPS) the lowest;CFCs varied with each additive; and a strong correlation was observed between Kte and life. The potential for accelerated MWF testing was outlined.

Metalworking fluids (MWFs) can greatly improve the machinability of materials and increase cutting tool life. There are a range of MWF products available on the market, however there are very few reliable low cost machining based fluid screening tests which can help select the most suitable candidate. This study developed a novel and rigorous single point milling (SPM) procedure carried out under controlled conditions, which would provide fluid performance differentiation for a range of typical aerospace alloys. The use of a single insert with a controlled geometry reduced machining variance and ensured performance repeatability. Tool life curves were used to determine optimum machining surface speeds for Inconel 718 (In718) of 80 m/min and Ti-6Al-4V (Ti64) of 160 m/min. Carrying out trials using five different cutting fluid products within a controlled tool life window clearly demonstrated that the SPM machining test was able to differentiate performance on both In718 and Ti64 material. Overall a 65% and 53% performance difference in tool life behaviour was observed between the best and worst performing fluids for In718 and Ti64, respectively.

Background and Purpose: Dual antiplatelet therapy (DAPT), compared to single antiplatelet therapy (SAPT), lowers the risk of stroke or death early after TIA and minor ischemic stroke. Prior trials excluded moderate to severe strokes, due to a potential increased risk of bleeding. We aimed to compare in-hospital bleeding rates in SAPT and DAPT patients with moderate or severe stroke (defined by NIHSS ≥4).Methods: We performed a retrospective cohort study of ischemic stroke over a 2-year period with admission NIHSS ≥4. The primary outcome was symptomatic intracranial hemorrhage (ICH) with any change in NIHSS. Secondary outcomes included systemic bleeding and major bleeding, a composite of serious systemic bleeding and symptomatic ICH. We performed analyses stratified by stroke severity (NIHSS 4–7 vs. 8+) and by preceding use of tPA and/or thrombectomy. Univariate followed by multivariate logistic regression evaluated whether DAPT was independently associated with bleeding.Results: Of 377 patients who met our inclusion criteria, 148 received DAPT (39%). Symptomatic ICH was less common with DAPT compared to SAPT (0.7 vs. 6.4%, p < 0.01), as was the composite of major bleeding (2.1 vs. 7.6%, p = 0.03). Symptomatic ICH was numerically less frequent in the DAPT group, but not statistically significant, when stratified by stroke severity (NIHSS 4–7: 0 vs. 5.9%, p = 0.06; NIHSS 8+: 1.5 vs. 6.6%, p = 0.18) and by treatment with tPA and/or thrombectomy (Yes: 2.6 vs. 9.1%, p = 0.30; No: 0 vs. 2.9%, p = 0.25). DAPT was not associated with major bleeding in either the univariate or the multivariate regression.Conclusions: In this single center cohort, symptomatic ICH and the composite of serious systemic bleeding and symptomatic ICH was rare in patients on DAPT. Relative to single antiplatelet therapy DAPT was not associated with an increased risk of in-hospital bleeding in patients with moderate and severe ischemic stroke.

OBJECTIVE: To compare subthalamic nucleus (STN) deep brain stimulation (DBS) with globus pallidus interna (GPi) DBS for tremor suppression in Parkinson disease (PD). BACKGROUND: DBS is an effective surgical therapy that has been shown to provide significant benefit for motor symptoms in PD. Currently, two main structures targeted to treat motor complications in PD are the STN and GPi. Although some groups traditionally favor STN over GPi for tremor suppression, evidence demonstrating superiority in long-term tremor control is limited. METHODS: We performed a systematic review for all randomized trials comparing STN vs GPi DBS in PD that were published before March 2017. Five studies were examined in a random effects model meta-analysis. We conducted moderator variable analysis to determine if there was a treatment effect difference for STN versus GPi. RESULTS: We compared DBS ON versus OFF and found a significant overall standardized difference mean effect: Effect Size = 0.36; 95% CI = 0.316–0.395; P < 0.0001. These findings indicate that DBS reduced tremor symptoms in PD patients with a medium effect size. Moderator variable analysis of STN vs GPI revealed two significant standardized effect sizes: STN effect size = 0.38 and GPi effect size = 0.35. A Z-test showed that effect sizes between the STN and GPi were not significantly different (P = 0.56). CONCLUSIONS: DBS is effective in reducing tremor in PD patients regardless of stimulation target. However, the degree of tremor suppression in STN DBS versus GPi DBS was equivalent.

Water based metalworking fluids (MWFs) commonly used for cooling and lubrication during machining are utilised in combination with cutting tools, work materials, fixtures and machine tools. However, they are an often overlooked component of the overall machining process, despite the fact that in some reported cases MWF costs were twice that of tooling costs. During its life cycle in a machine tool, the MWF is exposed to changes due to a range of factors which impact its quality and longevity. The key process variables (KPVs) reviewed in this study are MWF concentration, hydraulic (tramp) oil, solid particulates, water quality, MWF pH and microbial contamination. The aim of the present work is to highlight these KPVs which impact machining quality and health and safety, and to present industrially applicable measurement, monitoring and control (MMC) methods and techniques. This review is supported by a machining case study which demonstrates the impact of a single KPV—hydraulic (tramp) oil on MWF quality and machining output, and the need for applying MMC methods. Continuous hydraulic (tramp) oil contamination into the cutting fluid can cause tool life and wear to vary by 70%. A novel quantification methodology with gas chromatography was developed in this study to quantitatively measure hydraulic (tramp) oil contamination present within MWF and verified through experiments. The study overall highlights the need to apply a strict maintenance programme to increase the MWF lifetime and maintain performance for improved production, experimental process control and operator health and safety.

OBJECTIVE: To evaluate the etiology and discharge outcome of non-traumatic intracerebral hemorrhage (ICH) in young adults admitted to a comprehensive stroke center. METHODS: A retrospective chart review was performed on patients with a discharge diagnosis of non-traumatic ICH admitted from 7/1/2011 to 6/30/2016. Data was collected on demographics, clinical history, ICH score, hemorrhage location, do-not-resuscitate (DNR) orders, likely etiology, and discharge disposition. Categorical data was reported as percentage. Chi-squared test was performed to evaluate association of location of ICH, etiology of ICH, and ICH score with the discharge outcome. RESULTS: Sixty-three patients met the study criteria, with mean age 35.4 ± 6.4 years including 26 (41%) women and 40 (64%) whites. Headache (65%) and change in mental status (48%) were the most common presenting symptoms. Hemorrhage was most commonly seen in the deep structures in 29 (46%) patients followed by lobar ICH in 14 (22%) patients. The most common etiology of ICH was hypertension in 23 (37%) patients, followed by vascular abnormalities in 18 (29%) patients. Forty-two (67%) had good outcome defined as discharge to home (n=25) or acute inpatient rehabilitation (n=17). Twenty-one (33%) patients had bad outcome with discharge to skilled nursing facility (n=6), hospice (n=1) or died in the hospital (n=14). Hospital DNR orders were noted in 11 (18%) patients. Higher ICH score (p