Performance Analysis On A Variable Capacity Swash Plate Compressor

A numerical study on the performance of a variable capacity swash plate compressor for an automotive air-conditioning system was carried out. The compressor under investigation had six cylinders and capacity regulation was made by changing the swash plate inclination angle. A numerical simulation program was made based on mathematical modelings on the swash plate dynamics, refrigerant states in various control volumes such as cylinders and crank room, and flows in the opening passages of electric control valve for crank room pressure control. The simulation results such as mass flow rate, compressor power consumption, cooling capacity and COP were compared with measurements within ±5% deviation over various operating conditions except at low operating speed such as idling condition. By using the simulation program, the effect of the crank room pressure on the swash plate inclination angle and the determination of the crank room pressure level by the electric control valve openings could be investigated

The impact of dose of the angiotensin-receptor blocker valsartan on the post-myocardial infarction ventricular remodeling: study protocol for a randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>Angiotensin-converting enzyme inhibitors and the angiotensin-receptor blocker valsartan ameliorate ventricular remodeling after myocardial infarction (MI). Based on previous clinical trials, a maximum clinical dose is recommended in practical guidelines. Yet, has not been clearly demonstrated whether the recommended dose is more efficacious compared to the lower dose that is commonly used in clinical practice.</p> <p>Method/Design</p> <p>Valsartan in post-MI remodeling (VALID) is a randomized, open-label, single-blinded multicenter study designed to compare the efficacy of different clinical dose of valsartan on the post-MI ventricular remodeling. This study also aims to assess neurohormone change and clinical parameters of patients during the post-infarct period. A total of 1116 patients with left ventricular dysfunction following the first episode of acute ST-elevation MI are to be enrolled and randomized to a maximal tolerable dose (up to 320 mg/day) or usual dose (80 mg/day) of valsartan for 12 months in 2:1 ratio. Echocardiographic analysis for quantifying post-MI ventricular remodeling is to be conducted in central core laboratory. Clinical assessment and laboratory test are performed at fixed times.</p> <p>Discussion</p> <p>VALID is a multicenter collaborative study to evaluate the impact of dose of valsartan on the post-MI ventricular remodeling. The results of the study provide information about optimal dosing of the drug in the management of patients after MI. The results will be available by 2012.</p> <p>Trial registration</p> <p><a href="http://www.clinicaltrials.gov/ct2/show/NCT01340326">NCT01340326</a></p

Atrasentan and renal events in patients with type 2 diabetes and chronic kidney disease (SONAR): a double-blind, randomised, placebo-controlled trial

Background: Short-term treatment for people with type 2 diabetes using a low dose of the selective endothelin A receptor antagonist atrasentan reduces albuminuria without causing significant sodium retention. We report the long-term effects of treatment with atrasentan on major renal outcomes. Methods: We did this double-blind, randomised, placebo-controlled trial at 689 sites in 41 countries. We enrolled adults aged 18–85 years with type 2 diabetes, estimated glomerular filtration rate (eGFR)25–75 mL/min per 1·73 m 2 of body surface area, and a urine albumin-to-creatinine ratio (UACR)of 300–5000 mg/g who had received maximum labelled or tolerated renin–angiotensin system inhibition for at least 4 weeks. Participants were given atrasentan 0·75 mg orally daily during an enrichment period before random group assignment. Those with a UACR decrease of at least 30% with no substantial fluid retention during the enrichment period (responders)were included in the double-blind treatment period. Responders were randomly assigned to receive either atrasentan 0·75 mg orally daily or placebo. All patients and investigators were masked to treatment assignment. The primary endpoint was a composite of doubling of serum creatinine (sustained for ≥30 days)or end-stage kidney disease (eGFR <15 mL/min per 1·73 m 2 sustained for ≥90 days, chronic dialysis for ≥90 days, kidney transplantation, or death from kidney failure)in the intention-to-treat population of all responders. Safety was assessed in all patients who received at least one dose of their assigned study treatment. The study is registered with ClinicalTrials.gov, number NCT01858532. Findings: Between May 17, 2013, and July 13, 2017, 11 087 patients were screened; 5117 entered the enrichment period, and 4711 completed the enrichment period. Of these, 2648 patients were responders and were randomly assigned to the atrasentan group (n=1325)or placebo group (n=1323). Median follow-up was 2·2 years (IQR 1·4–2·9). 79 (6·0%)of 1325 patients in the atrasentan group and 105 (7·9%)of 1323 in the placebo group had a primary composite renal endpoint event (hazard ratio [HR]0·65 [95% CI 0·49–0·88]; p=0·0047). Fluid retention and anaemia adverse events, which have been previously attributed to endothelin receptor antagonists, were more frequent in the atrasentan group than in the placebo group. Hospital admission for heart failure occurred in 47 (3·5%)of 1325 patients in the atrasentan group and 34 (2·6%)of 1323 patients in the placebo group (HR 1·33 [95% CI 0·85–2·07]; p=0·208). 58 (4·4%)patients in the atrasentan group and 52 (3·9%)in the placebo group died (HR 1·09 [95% CI 0·75–1·59]; p=0·65). Interpretation: Atrasentan reduced the risk of renal events in patients with diabetes and chronic kidney disease who were selected to optimise efficacy and safety. These data support a potential role for selective endothelin receptor antagonists in protecting renal function in patients with type 2 diabetes at high risk of developing end-stage kidney disease. Funding: AbbVie

Covalent stabilization of inverse bicontinuous cubic structures of block copolymer bilayers by photodimerization of indene pendant groups of polystyrene hydrophobic blocks

We report the cross-linking of hydrophobic compartments of complex self-assembled structures of amphiphilic block copolymers (BCPs) by the [2?? + 2??]-cycloaddition of indene moieties present in a hydrophobic block based on polystyrene (PS). A photodimerizable indene group was introduced to the PS block by controlled radical copolymerization of indanolylstyrene, which was subsequently dehydrated to indenylstyrene using the Burgess reagent. This mild conversion producing the photodimerizable indene pendant groups ensured the synthesis of BCPs with a photo-cross-linkable PS block. We demonstrate that the micellar structures and complex inverse bicontinuous bilayers of BCPs containing hydrophobic PS cores could be covalently cross-linked in aqueous solutions upon irradiation with long-wavelength UV light (?? = 365 nm). The procedure formed an infinite polymer network within the hydrophobic compartments of the self-assembled nanostructures without using any additional reagents or causing morphological changes during the cross-linking. A wide variety of self-assembled structures retained their structural integrity in common organic solvents after cross-linking of the hydrophobic PS blocks.ope

Synthesis of 1,2-amino alcohols via catalytic C–H amidation of sp3 methyl C–H bonds

Herein a new synthetic route to 1,2-amino alcohols is presented by using C.H amidation of sp3 methyl C.H bonds as a key step. Readily available alcohols were employed as starting materials after converting them to removable ketoxime chelating groups. Iridium catalysts were found to be effective for the C.H amidation, and LAH reduction was then used to furnish b-amino alcohol products.145461sciescopu

Arthroscopic-Assisted Middle Trapezius Transfer Using an Achilles Tendon Allograft in Treatment of Isolated Supraspinatus Irreparable Rotator Cuff Tears in Lateral Decubitus Position

The optimal treatment for patients diagnosed with isolated supraspinatus irreparable rotator cuff tears continues to be a subject of debate. Joint-preserving methods, including partial repair, superior capsule reconstruction, balloon spacers, and tendon transfer, have been introduced. Among these options, the middle trapezius tendon (MTT) transfer has garnered attention for its potential to replace the irreparable portion of the supraspinatus tendon and provide dynamic stability to the joint. Although some reports have highlighted promising clinical outcomes of MTT, there remains a dearth of literature regarding the techniques and methods involved in the surgical procedure. This Technical Note introduces an arthroscopic-assisted technique for MTT transfer using an Achilles tendon allograft for patients diagnosed with isolated supraspinatus irreparable rotator cuff tears in lateral decubitus