bluuebunny/crossref_metadata_2025 huggingface dataset:
Associations of snoring frequency and intensity in pregnancy with time‐to‐delivery
Authors: Dunietz Galit Levi , Shedden Kerby , Schisterman Enrique F. , Lisabeth Lynda D. , Treadwell Marjorie C. , O'Brien Louise M.
Published: September 2018

Background

Sleep‐disordered breathing (SDB) is linked to adverse pregnancy outcomes. However, little is known about the association of SDB with timing of delivery. We examined the association of snoring frequency, a key SDB marker, and snoring intensity, a correlate of SDB severity, with time‐to‐delivery among a cohort of pregnant women.

Methods

In this prospective cohort study, 1483 third trimester pregnant women were recruited from the University of Michigan prenatal clinics. Women completed a questionnaire about their sleep, and demographic and pregnancy information was abstracted from medical charts. After exclusion of those with hypertension or diabetes, 954 women were classified into two groups by their snoring onset timing, chronic or pregnancy‐onset. Within each of these groups, women were divided into four groups based on their snoring frequency and intensity: non‐snorers; infrequent‐quiet; frequent‐quiet; or frequent‐loud snorers. Cox proportional hazard regression models were used to investigate the association between snoring frequency and intensity and time‐to‐delivery, adjusting for maternal characteristics.

Results

Chronic snoring was reported by half of the pregnant women, and of those, 7% were frequent‐loud snorers. Deliveries before 38 weeks’ gestation are completed occurred among 25% of women with chronic, frequent‐loud snoring. Compared with pre‐pregnancy non‐snorers, women with chronic frequent‐loud snoring had an increased hazard ratio for delivery (adjusted hazard ratio 1.60, 95% confidence interval 1.04, 2.45).

Conclusions

Snoring frequency and intensity is associated with time‐to‐delivery in women absent of hypertension or diabetes. Frequent‐loud snoring may have a clinical utility to identify otherwise low‐risk women who are likely to deliver earlier.
Increased vascular function and superoxide dismutase activity in physically active vs inactive adults living with HIV
Authors: Lopes Gabriella O. , Farinatti Paulo , Lopes Karynne G. , Medeiros‐Lima Daniel J. , Matsuura Cristiane , Oliveira Ricardo B. , Bouskela Eliete , Bottino Daniel A. , Muccillo Fabiana , Tibirica Eduardo , Borges Juliana P.
Published: September 2018

This study compared macro‐ and microvascular endothelial function and redox status in active vs inactive HIV‐infected patients (HIVP) under antiretroviral therapy. Using a cross‐sectional design, macro‐ and microvascular reactivity, systemic microvascular density, and oxidative stress were compared between 19 HIVP (53.1 ± 6.1 year) enrolled in a multimodal training program (aerobic, strength and flexibility exercises) for at least 12 months (60‐minutes sessions performed 3 times/wk with moderate intensity) vs 25 sedentary HIVP (51.2 ± 6.3 year). Forearm blood flow during reactive hyperemia (521.7 ± 241.9 vs 361.4% ± 125.0%; P = 0.04) and systemic microvascular density (120.8 ± 21.1 vs 105.6 ± 25.0 capillaries/mm2; P = 0.03) was greater in active than inactive patients. No significant difference between groups was detected for endothelium‐dependent and independent skin microvascular vasodilation (P > 0.05). As for redox status, carbonyl groups (P = 0.22), lipid peroxidation (P = 0.86), catalase activity (P = 0.99), and nitric oxide levels (P = 0.72) were similar across groups. However, superoxide dismutase activity was greater in active vs inactive HIVP (0.118 ± 0.013 vs 0.111 ± 0.007 U/mL; P = 0.05). Immune function reflected by total T CD4 and T CD8 counts (cell/mm3) did not differ between active and inactive groups (P > 0.82). In conclusion, physically active HIVP exhibited similar immune function, but greater macrovascular reactivity, systemic microvascular density, and superoxide dismutase activity than inactive patients of similar age.
Jasmonic acid‐inducible TSA1 facilitates ER body formation
Authors: Geem Kyoung Rok , Kim Dae Heon , Lee Dong Wook , Kwon Yun , Lee Junho , Kim Jeong Hee , Hwang Inhwan
Published: September 2018

Members of the Brassicales contain an organelle, the endoplasmic reticulum (ER) body, which is derived from the ER. Recent studies have shed light on the biogenesis of the ER body and its physiological role in plants. However, formation of the ER body and its physiological role are not fully understood. Here, we investigated the physiological role of TSK‐associating protein 1 (TSA1), a close homolog of NAI2 that is involved in ER body formation, and provide evidence that it is involved in ER body biogenesis under wound‐related stress conditions. TSA1 is N‐glycosylated and localizes to the ER body as a luminal protein. TSA1 was highly induced by the plant hormone, methyl jasmonate (MeJA). Ectopic expression of TSA1:GFP induced ER body formation in root tissues of transgenic Arabidopsis thaliana and in leaf tissues of Nicotiana benthamiana. TSA1 and NAI2 formed a heterocomplex and showed an additive effect on ER body formation in N. benthamiana. MeJA treatment induced ER body formation in leaf tissues of nai2 and tsa1 plants, but not nai2/tsa1 double‐mutant plants. However, constitutive ER body formation was altered in young seedlings of nai2 plants but not tsa1 plants. Based on these results, we propose that TSA1 plays a critical role in MeJA‐induced ER body formation in plants.
How we evaluate red blood cell compatibility and transfusion support for patients with sickle cell disease undergoing hematopoietic progenitor cell transplantation
Authors: Allen Elizabeth S. , Nelson Randin C. , Flegel Willy A.
Published: September 2018

Multiple hematopoietic progenitor cell (HPC) transplantation options for patients with sickle cell disease (SCD) are currently under investigation. Patients with SCD have a high rate of alloimmunization to red blood cell antigens, often complicating transfusion support. Transfusion reactions, including acute and delayed hemolytic reactions, have been observed despite immunosuppressive regimens. Allogeneic donor transplants have been shown to carry a risk of prolonged reticulocytopenia and acute hemolysis with severe anemia in nonmyeloablative regimens. We discuss our experience providing transfusion support to patients with SCD undergoing HPC transplantation, propose an outline for a complete pretransplantation evaluation, and discuss donor/recipient compatibility issues and their implications.
High‐dose intravenous immunoglobulin is strongly associated with hemolytic anemia in patients with Kawasaki disease
Authors: Nolan Brian E. , Wang Yunfei , Pary Philippe P. , Luban Naomi L.C. , Wong Edward C.C. , Ronis Tova
Published: September 2018

BACKGROUND

Hemolysis is a reported side effect of intravenous immunoglobulin (IVIG) therapy in adults, but pediatric data are scarce. We determined the frequency of IVIG‐associated hemolysis in patients with Kawasaki disease (KD) and characterized risk factors for hemolysis. We hypothesized that hemolysis is more common in children with KD than adults with other disorders, and hemolysis risk is related to IVIG dose and degree of inflammation.

STUDY DESIGN AND METHODS

This was an 8‐year, single‐center, retrospective cohort study. A total of 419 KD patients were identified; 123 had pre‐ and post‐treatment complete blood counts allowing for assessment of anemia. Hemolytic anemia was defined as decrease in hemoglobin after IVIG greater than 1 g/dL with immunohematologic or biochemical studies supporting hemolysis.

RESULTS

123 patients were stratified as having hemolysis (n = 18, 15%) or nonhemolysis (n = 105, 85%). Patients with hemolysis were more likely to have complete versus incomplete KD (65% vs. 39%, p = 0.04) and refractory versus nonrefractory course (78% vs. 16%, p < 0.001). Patients receiving 4 g/kg versus 2 g/kg IVIG were more likely to hemolyze (89% vs. 34%, p < 0.001). Patients with hemolysis had mostly non‐O blood group (94%), positive direct antiglobulin tests (89%), and positive eluates (72%). Two‐thirds of patients with hemolysis required RBC transfusion.

CONCLUSIONS

Hemolysis occurred in 15% of KD patients evaluated for anemia and is strongly associated with high‐dose (4 g/kg) IVIG. KD patients receiving high‐dose IVIG should have close hematologic monitoring to identify hemolysis.
Successful engraftment after cord blood transplantation from an HLA‐homozygous donor (homo‐to‐hetero cord blood transplantation) in a primary myelofibrosis patient with broad HLA antibodies
Authors: Iemura Tomoki , Itoh Mitsuru , Mano Chihiro , Oba Akifumi , Kawabata Norihiro , Horisawa Yoshihito , Matsui Masashi , Miyahara Yasuko , Kanda Junya
Published: September 2018

BACKGROUND

Donor‐specific human leukocyte antigen (HLA) antibodies are a significant risk factor for graft failure in cord blood transplantation (CBT). Although there are several treatments to decrease HLA antibodies, such as platelet transfusion, plasma exchange, rituximab, and bortezomib, their effectiveness has not been established.

STUDY DESIGN AND METHODS

We herein report the case of a primary myelofibrosis (PMF) patient with broad HLA antibodies who underwent CBT from an HLA‐homozygous donor in which the alleles were matched only in the host‐versus‐graft direction (homo‐to‐hetero CBT).

RESULTS

The cord blood was killer cell immunoglobulin‐like receptor (KIR) ligand matched. She received a reduced‐intensity conditioning regimen. We used tacrolimus and mycophenolate mofetil as prophylaxis against graft‐versus‐host disease (GVHD). The neutrophils engrafted on Day 31. A chimerism analysis with fluorescence in situ hybridization of peripheral blood cells showed 99.9% donor type on Day 33. She developed only mild acute skin GVHD and chronic skin GVHD.

CONCLUSION

This case indicates the usefulness of homo‐to‐hetero CBT in a patient with broad HLA antibodies with a strong mean fluorescence intensity, which is a significant risk factor for graft failure. Further studies are necessary to determine the risk of GVHD and to elucidate the association between KIR ligand incompatibility and graft failure in homo‐to‐hetero CBT.
Distinct effects of daratumumab on indirect and direct antiglobulin tests: a new method employing 0.01 mol/L dithiothreitol for negating the daratumumab interference with preserving K antigenicity (Osaka method)
Authors: Hosokawa Mika , Kashiwagi Hirokazu , Nakayama Kotarosumitomo , Sakuragi Mikiko , Nakao Mayumi , Morikawa Tamayo , Kiyokawa Tomoko , Aochi Hiroshi , Nagamine Keisuke , Shibayama Hirohiko , Tomiyama Yoshiaki
Published: September 2018

BACKGROUND

There is an increasing demand for daratumumab (DARA), an immunoglobulin (Ig)G1κ monoclonal antibody (MoAb) that recognizes CD38, to manage relapsed or refractory multiple myeloma (MM) patients. However, DARA leads to positive and panreactive agglutination reactions in indirect antiglobulin tests (IATs) in vitro (the DARA interference). In addition, effects of DARA on red blood cells (RBCs) in vivo remains elusive.

STUDY DESIGN AND METHODS

To develop a new method to negate the DARA interference, the effects of various concentrations of dithiothreitol (DTT) on RBC CD38 and Kell antigenicity in combination with an automatic blood cell washing centrifuge were compared with the AABB standard procedure in parallel. Moreover, direct antiglobulin tests (DATs) for RBCs in DARA‐treated MM patients were examined.

RESULTS

A quantity of 0.01 mol/L DTT as well as the AABB procedure (equivalent to 0.15 mol/L DTT in our procedure) markedly reduced the reactivity of phycoerythrin‐mouse anti‐CD38 MoAb and DARA with RBCs. In sharp contrast to the AABB procedure, 0.01 mol/L DTT partially preserved K antigenicity and allowed the determination of phenotype of K antigen even in the presence of the DARA interference. In contrast, DAT for RBCs obtained from MM patients showed a weak positive or negative reaction. Immunoblotting further indicated that DARA induced loss of CD38 in vivo.

CONCLUSION

A simple and reliable method to negate the DARA interference with partially preserving Kell antigenicity is proposed (Osaka method). CD38 antigenicity is susceptible to 0.01 mol/L DTT treatment even in the presence of DARA. Our data also demonstrate distinct effects of DARA on IAT in vitro and DAT in vivo.
Platelet storage in more than 90% additive solution containing glucose and bicarbonate has the potential to increase shelf life
Authors: Bashir Saber , Kemsley Kelly , Min Kyungyoon , Swann Ian D. , Cardigan Rebecca
Published: September 2018

BACKGROUND

Platelet concentrates (PCs) suspended in more than 90% additive solution (AS) are recommended for patients with reactions to platelets stored in plasma. Next‐generation AS containing glucose and bicarbonate might enable storage of these PCs for longer than those in current‐generation AS, which was therefore evaluated in this study.

STUDY DESIGN AND METHODS

Five buffy coat or apheresis‐derived PCs were pooled and split into identical units. All units except the control were centrifuged, the plasma removed and replaced with AS (SSP+, PAS‐5, or PAS‐G), or resuspended in the same plasma and sampled 96 hours after resuspension for analysis.

RESULTS

Plasma carryover was less than 10%, total protein less than 1 g/unit, and immunoglobulin A levels lower than 0.1 mg/mL for all PCs in AS. The pH of all the platelets during storage was higher than 6.4. PAS containing glucose maintained superior in vitro platelet function during storage compared with those resuspended in SSP+. Compared with storage in SSP+, storage in PAS‐5 or PAS‐G resulted in better preservation of platelet adenosine triphosphate and hypotonic shock response, lower annexin V binding, and improved mitochondrial membrane potential.

CONCLUSION

Platelets resuspended in PAS‐5 and PAS‐G maintained in vitro function and metabolism during storage compared with SSP+ platelets. Elevated platelet metabolic activity was noticed in PAS‐G, and higher platelet activation was detected with PAS‐5. Platelets resuspended in PAS containing glucose has the potential to increase the shelf life of PC in more than 90% AS.
In vitro effects of the chemotherapy agent water‐soluble micellar paclitaxel (Paccal Vet) on canine hemangiosarcoma cell lines
Authors: Reckelhoff Caroline R. , Lejeune Amandine , Thompson Patrick M. , Shiomitsu Keijiro
Published: September 2018

Paccal Vet (Osamia Pharmaceuticals) is a water‐soluble nanoparticle micellar formulation of the drug paclitaxel that is well tolerated in dogs. This study evaluated the in vitro effect of Paccal Vet on two canine hemangiosarcoma (HSA) cell lines and their expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). Paccal Vet caused HSA cell death in a dose‐ and time‐dependent manner. The 50% inhibitory concentration (IC50) for the two HSA cell lines were 7 to 610 ng/mL, which are clinically achievable. Cell cycle analysis through flow cytometry showed cell cycle arrest at G2/M phase. Annexin‐V and caspase 3/7 activity assays showed significant increases in apoptosis in correlation with the IC50 in each cell line. Reverse transcriptase‐PCR was performed on the cell lines to validate the gene expression of VEGF and bFGF. Results obtained from this study support future studies involving the use of paclitaxel (micellar) for treatment of canine HSA.
Management of total hip replacement luxation with triple pelvic osteotomy
Authors: Monotti Isobel C. , Ryan Stewart D. , Preston Chris A.
Published: September 2018

Objective

To report the outcome of dogs treated with triple pelvic osteotomy (TPO) for dorsal luxation after total hip replacement (THR).

Study design

Retrospective clinical case series.

Animals

Seventeen client‐owned animals.

Methods

Medical records were searched at a single institution for dogs that had been treated with TPO for dorsal THR luxation. The angle of lateral opening (ALO), version angle (VA), and inclination angle (IA) were measured from radiographs after THR and TPO and corrected for pelvic rotation. A pairedttest was performed to compare cup orientation after THR and TPO. Functional outcome was assessed at follow‐up examination and during telephone interviews.

Results

Eighteen TPOs were performed in 17 dogs, and radiographs were available for 15 cases. Open and/or closed hip reduction with additional stabilization was attempted unsuccessfully in 6 dogs prior to TPO. Triple pelvic osteotomy reduced the ALO by a mean of 23.0 ° ± 10.9 ° (P ≤ .001), increased VA by 9.0 ° ± 4.9 ° (P < .001), and increased IA by 2.9 ° ± 5.8 ° (P = .126). An excellent or good outcome was achieved in 12 dogs. Ventral luxation occurred in 3 dogs, and dorsal luxation occurred in 1 dog after TPO. Triple pelvic osteotomy excessively reduced ALO in 2 dogs with ventral luxation.

Conclusion

Triple pelvic osteotomy with cup retention is a viable alternative to cup revision for treatment of dorsal luxation of cemented and cementless THR. Triple pelvic osteotomy significantly reduces ALO and increases VA. Careful patient selection is recommended because excessive ventroversion can lead to ventral luxation.

Clinical significance

Triple pelvic osteotomy offers a revision option that preserves the implant–bone interface and significantly reduces ALO. This technique may be appropriate in dogs with high ALO, luxoid hips, and prior failed revision attempts.
Radical cystectomy and subsequent ureterohysterostomy in a bitch
Authors: Delaune Tiare , Bernard Fabrice , Matres‐Lorenzo Luis , Bernardé Antoine
Published: September 2018

Objective

To describe and report the outcome of a ureterouterine anastomosis after unilateral dehiscence of a ureterovaginal anastomosis after total cystectomy in a bitch.

Study design

Case report.

Animal

A 10‐year‐old intact female border collie with a urinary bladder leiomyosarcoma.

Methods

The dog was diagnosed with an invasive urinary bladder tumor, treated by radical cystectomy and bilateral ureterovaginal anastomosis. Postoperative necrosis of the distal ureter led to dehiscence of the anastomosis on the right side. To preserve the right kidney, the right ureter was anastomosed to the right uterine horn, and a stent was placed across the uterine cervix.

Results

The dog recovered from surgery and regained satisfactory urine output. Both ureteral anastomoses were patent at 10 months postoperatively. At 12 months postoperatively, intraluminal obstruction of the uterine stent, loss of patency of the right ureter, and severe right renal hydronephrosis were noted. The owner declined nephrectomy, and the dog died 2 months later.

Conclusion

This is the first published report of a ureterouterine anastomosis and stenting of the uterine cervix in a dog. The functional outcome was satisfactory for 1 year postoperatively. The uterine stent and distal ureter were eventually obstructed by soft tissue.

Clinical significance

Ureterouterine anastomosis can be considered as a salvage procedure when other surgical techniques have failed.
Teaching and proficiency assessment for arthroscopy in veterinary surgery: A 2017 survey of diplomates and residents of the American and European College of Veterinary Surgeons
Authors: Maurin Marie‐Pauline , Pozzi Antonio , Bleedorn Jason , McNally Turlough P. , Cuddy Laura C.
Published: September 2018

Objective

To determine current methods of arthroscopic skills training and proficiency assessment, identify skills considered fundamental to arthroscopy, and evaluate desire for a formal training and assessment program.

Study design

Anonymized electronic survey.

Sample population

Diplomates and residents of the American College of Veterinary Surgeons (ACVS) and European College of Veterinary Surgeons (ECVS).

Methods

An electronic survey was distributed in commercial software (Qualtrics, Provo, Utah). Questions were divided into 4 categories: (1) demographics, (2) arthroscopy experience, (3) teaching, and (4) proficiency assessment. Descriptive statistical analysis was performed. Comparisons between groups were performed by using χ2,ttests, and 1‐way ANOVA (P ≤ .05).

Results

In total, 429 diplomates and 149 residents responded (response rate 28%). Overall, 80% of respondents trained using clinical cases. Barriers to simulator training included cadaver/simulator availability and time. Skills deemed most fundamental included anatomic knowledge, precise portal placement, triangulation, and image orientation. Overall, 90% of respondents supported a formal training program with requirement to demonstrate proficiency; 80% believed this should be part of standard ACVS/ECVS residency training.

Conclusion

Arthroscopic skills are taught by using clinical cases, with subjective proficiency assessment. Fundamental skills are those that may be taught using simulators. There is enthusiasm for formal arthroscopic skills training and assessment.

Clinical significance

Improved acquisition and assessment of fundamental arthroscopic skills is indicated. A validated methodology for formal training using simulators, minimizing morbidity, and facilitating objective evaluation is warranted. This is the first phase of a project to develop and validate a simulator program.
A prospective, randomized, double‐blinded, placebo‐controlled clinical study on postoperative antibiotherapy in 150 arthroscopy‐assisted tibial plateau leveling osteotomies in dogs
Authors: Spencer Dustine D. , Daye R. Mark
Published: September 2018

Objective

To determine the influence of a 7‐day course of postoperative antibiotherapy (cefpodoxime) on surgical site infections (SSI) after tibial plateau leveling osteotomy (TPLO).

Study design

Prospective, randomized, double‐blinded, placebo‐controlled clinical study.

Sample population

One hundred fifty client‐owned dogs, with consent.

Methods

Dogs undergoing arthroscopy‐assisted TPLO were randomly assigned to 1 of 2 groups, the placebo group receiving perioperative cefazolin and 7 days of placebo medication after surgery or the treatment group receiving perioperative cefazolin and 7 days of postoperative cefpodoxime. Twenty‐seven factors were analyzed for association with SSI by using univariate analysis, Fisher's exact test, or Wilcoxon rank‐sum test.

Results

SSI rates did not differ (P = .34) between the placebo group (17%; 95% confidence level [CL] 7.94%‐26.43%) and the treatment group (11% SSI; 95% CL 3.98%‐18.88%). The probability that > 23% of dogs would benefit from postoperative antibiotherapy was less than 5%. The only association between the factors tested in this study and SSI involved the body weight (kg), with each 1 unit increase in kilogram weight increasing the odds of developing an SSI by 4.7%.

Conclusion

Although the wide CL may be consistent with a type II error, a 7‐day course of cefpodoxime after arthroscopy‐assisted TPLO did not influence postoperative SSI in the population tested here. In addition, only a small proportion of dogs would benefit from postoperative antibiotherapy under the conditions of our study.

Clinical significance

These results should prompt surgeons to reconsider systematic antibiotherapy after TPLO and justify additional studies to determine whether dogs predisposed to infection could benefit from such an approach.
Buckling of Magnetically Formed Filler Fiber Columns Under Compression Increases Thermal Resistance of Soft Polymer Composites
Authors: Ralphs Matthew , Scheitlin Chandler , Wang Robert Y. , Rykaczewski Konrad
Published: September 2018

Thermally conductive soft composites are in high demand, and aligning the fill material is a potential method of enhancing their thermal performance. In particular, magnetic alignment of nickel particles has previously been demonstrated as an easy and effective way to improve directional thermal conductivity of such composites. However, the effect of compression on the thermal performance of these materials has not yet been investigated. This work investigates the thermal performance of magnetically aligned nickel fibers in a soft polymer matrix under compression. The fibers orient themselves in the direction of the applied magnetic field and align into columns, resulting in a 3× increase in directional thermal conductivity over unaligned composites at a volume fraction of 0.15. Nevertheless, these aligned fiber columns buckle under strain resulting in an increase in the composite thermal resistance. These results highlight potential pitfalls of magnetic filler alignment when designing soft composites for applications where strain is expected such as thermal management of electronics.
On the Influence of an Acoustically Optimized Turbine Exit Casing Onto the Unsteady Flow Field Downstream of a Low Pressure Turbine Rotor
Authors: Simonassi Loris , Zenz Manuel , Zerobin Stefan , Selic Thorsten , Heitmeir Franz , Marn Andreas
Published: September 2018

Modern low pressure turbines (LPT) are designed in order to fulfil a various number of requirements such as high endurance, low noise, high efficiency, low weight, and low fuel consumption. Regarding the reduction of the emitted noise, different designs of LPT exit guide vanes (aerodynamically and/or acoustically optimized) of the turbine exit casing (TEC) were tested, and their noise reduction capabilities and aerodynamic performance were evaluated. In particular, measurements of TEC-losses were performed, and differences in the losses were reported. Measurements were carried out in a one and a half stage subsonic turbine test facility at the engine relevant operating point approach. This work focuses on the study of the unsteady flow field downstream of an unshrouded LPT rotor. The influence on the upstream flow field of a TEC design including acoustically optimized vanes (inverse cut-off TEC) is investigated and compared with a second TEC configuration without vanes (Vaneless TEC), by means of fast response aerodynamic pressure probe (FRAPP) measurements. The second configuration served as a reference concerning the influence of turbine exit guide vanes (TEGVs) onto the upstream located LPT rotor. The interactions between the stator and rotor wakes, secondary flows, and the TEGVs potential effect are identified via modal decomposition according to the theory of Tyler and Sofrin. The main structures constituting the unsteady flow field are detected, and the role of the major interaction effects in the loss generation mechanism and in the acoustic emission is analyzed. This study based on the modal analysis of the unsteady flow field offers new insight into the main interaction mechanisms and their importance in the assessment of the aerodynamic and aeroelastic performance of modern LPT exit casings.
A Study of Power Production and Noise Generation of a Small Wind Turbine for an Urban Environment
Authors: Hays Andrew , Van Treuren Kenneth W.
Published: September 2018

Wind energy has had a major impact on the generation of renewable energy. While most research and development focuses on large, utility-scale wind turbines, a new application is in the field of small wind turbines for the urban environment. A major design challenge for urban wind turbines is the noise generated during operation. This study examines the power production and the noise generated by two small-scale wind turbines tested in a small wind tunnel. Both rotors were designed using the blade-element momentum theory using either the NREL S823 or the Eppler 216 airfoils. Point noise measurements were taken using a microphone at three locations downstream of the turbine: 16% of the diameter (two chord lengths), 50% of the diameter, and 75% of the diameter. At each location downstream of the turbine, a vertical traverse was performed to analyze the sound pressure level (SPL) from the tip of the turbine blades down to the hub. The rotor designed with the Eppler 216 airfoil showed a 9% increase in power production and decrease of up to 7 dB(A).
Binary Biodiesel Blend Endurance Characteristics in a Compression Ignition Engine
Authors: Singh Paramvir , Chauhan S. R. , Goel Varun , Gupta Ashwani K.
Published: September 2018

The results obtained on wear assessment from a compression ignition (CI) engine fueled with a blend of 70% amla seed biodiesel (AB) and 30% eucalyptus oil (EU) on volume basis (called AB70EU30). The results showed stable engine operation and good operability of the engine-fuel system with the binary biodiesel fuel blend. The feasibility of this blend over a long-term endurance tests was explored. The specific assessment examination included the fate of cylinder head, pump plunger, injector nozzle, and piston crown, which affects the engine performance and engine life. The experimental results revealed better tribological performance characteristics with the binary fuel blend as compared to contemporary diesel fuel. No specific problem was encountered during the long-term endurance tests with the binary fuel blend using the modified engine parameters. The results show that the binary fuel mixture offers good potential for use as diesel fuel in CI engines while maintaining good performance and endurance.
Effects of Homogeneous–Heterogeneous Reactions and Convective Condition in Darcy–Forchheimer Flow of Carbon Nanotubes
Authors: Alshomrani Ali Saleh , Ullah Malik Zaka
Published: September 2018

This paper presents Darcy–Forchheimer three-dimensional (3D) flow of water-based carbon nanotubes (CNTs) with heterogeneous–homogeneous reactions. A bi-directional linear extendable surface has been employed to create the flow. Flow in porous space is represented by Darcy–Forchheimer expression. Heat transfer mechanism is explored through convective heating. Equal diffusion coefficients are considered for both autocatalyst and reactants. Results for single-wall carbon nanotube (SWCNT) and multiwall carbon nanotube (MWCNT) have been presented and compared. The diminishment of partial differential framework into nonlinear ordinary differential framework is made through suitable transformations. Optimal homotopy scheme is used for arrangements development of governing flow problem. Optimal homotopic solution expressions for velocities and temperature are studied through plots by considering various estimations of physical variables. The skin friction coefficients and local Nusselt number are analyzed through plots. Our findings depict that the skin friction coefficients and local Nusselt number are enhanced for larger values of the nanoparticles volume fraction.
Sensitivity of On-Skin Thermometry to Detecting Dermal Dehydration
Authors: Sun Edward , Ma Jun , Salapaka Srinivasa , Sinha Sanjiv
Published: September 2018

The recent development of flexible sensors that can measure temperatures at the surface of the skin opens novel possibilities for continuous health monitoring. Here, we investigate such sensors as 3ω thermometers to noninvasively detect deep dermal dehydration. Using numerical simulations, we calculate the temperature rise at the sensor at heating frequencies from 10 mHz to 10 Hz at varying levels of dehydration. The heating power in each case is limited to avoid burn injury. Our results indicate that 10–100 mHz frequencies are necessary to detect deep dermal dehydration. We show that the root-mean-square difference in temperature rise between normal and dermally dehydrated skin can be as high as 250 mK, which is detectable using lock-in techniques. Thermal contact resistance between the sensor and skin can dominate the signal when the resistance exceeds ∼10−3 Km2/W. This work provides quantitative limits for sensing human dehydration using noninvasive sensors that measure the thermal conductivity of the skin structure.
Obstructed View Factor Calculations for Multiple Obstructions in Closed Cavities
Authors: Mahmood Fiaz , Hu Huasi
Published: September 2018

The inertial confinement fusion (ICF) program has been mainly concentrating on the indirect drive approach for the last three decades, due to relaxed requirements on driver-beam uniformity and reduced sensitivity to hydrodynamic instabilities. The optimal designs are important for maximum conversion of driving energy to X-rays, and finally, symmetrical irradiation of the capsule. The view factor (VF) evaluation is an important parameter providing significant radiation heat transport information in specific geometries. The present study is aimed at the VF calculations for closed cavities. The VF calculations include the case of energy transfer from one infinitesimal surface element of the enclosure to other similar infinitesimal surface elements of the cavity. Similarly, the obstructed VF is also calculated when multiple obstructions are present in the cavity. Two distinct computer programs are developed by programming in FORTRAN-90 to evaluate unobstructed VF and obstructed VF for a square geometry. The calculations are based on the crossed strings method, which is more reliable for simple geometries. The shadow effect method is used for the obstructed VF calculations. The results of the developed programs are benchmarked using the summation rule. In the case of no obstacles in the cavity, VF calculations solely obey the summation rule. However, in the presence of obstacles in the cavity, obstructed VF calculations showed the acceptable difference in comparison with the summation rule.
Investigation on Combined Air and Water Injection in Francis Turbine Draft Tube to Reduce Vortex Rope Effects
Authors: Mohammadi Moona , Hajidavalloo Ebrahim , Behbahani-Nejad Morteza
Published: September 2018

In this paper, the effect of water, air, and their combined injection from two different injection points is studied in order to reduce vorticity effects in a draft tube of prototype turbine working at three operating points. The flow from spiral case to the end of draft tube is simulated using the shear stress transport k–ω turbulence and two-phase models. Using an appropriate validation method, acceptable results were obtained under the noninjection condition. To determine suitable number of points and inlet flow rate for air injection as well as the appropriate nozzle diameter for air and water injection, a new method which considers the ratio of total loss to the pressure recovery factor is used, in addition to using the traditional method which calculates the total loss in the draft tube. Comparing results of the three types of injections shows air injection in the operating range greater than 70% of turbine design flow rate, is much more effective than water injection or the combination of air and water injection. However, in the operating range below 70%, either water or air injections are not suitable, but combination of these two fluids can improve system performance.
An Optimal Parametrization Scheme for Path Generation Using Fourier Descriptors for Four-Bar Mechanism Synthesis
Authors: Sharma Shashank , Purwar Anurag , Jeffrey Ge Q.
Published: September 2018

Fourier descriptor (FD)-based path synthesis algorithms for generation of planar four-bar mechanisms require assigning time parameter values to the given points along the path. An improper selection of time parameters leads to poor fitting of the given path and suboptimal four-bar mechanisms while also ignoring a host of mechanisms that could be potentially generated otherwise. A common approach taken is to use uniform time parameter values, which does not take into account the unique harmonic properties of the coupler path. In this paper, we are presenting a nonuniform parametrization scheme in conjunction with an objective function that provides a better fit, leverages the harmonics of the four-bar coupler, and allows imposing additional user-specified constraints.
A Design Method to Improve End-of-Use Product Value Recovery for Circular Economy
Authors: Cong Liang , Zhao Fu , Sutherland John W.
Published: September 2018

Circular economy (CE) is being increasingly accepted as a promising sustainable business model, supporting waste minimization through product life cycles. The product end-of-use (EOU) stage is the key to circulate materials and components into a new life cycle, rather than direct disposal. The economic viability of recycling EOU products is significantly affected by designers' decisions and largely determined during product design. Low economic return of EOU value recovery is a major barrier to overcome. To address this issue, a design method to facilitate EOU product value recovery is proposed. First, product EOU scenarios are determined by optimization of EOU component flows. The EOU scenario depicts which modules (groups of components) will be allocated for reuse, recycling, or disposal, the order of joint detachment (the joints for modules connection), and recovery profit. Second, in the given study, bottlenecks, improvement opportunities, and design suggestions will be identified and provided following the EOU scenario analysis. Pareto analysis is used for ranking joints, according to their detachment cost and for indicating which joints are the most suitable for replacement. An analytic hierarchy process (AHP) is employed to select the best joint candidate with trade-off among criteria from the perspective of disassembly. In addition, disposal and recycling modules are checked to eliminate hazardous material and increase material compatibility. A value-based recycling indicator is developed to measure recyclability of the modules and evaluate design suggestions for material selection. Finally, based on heuristics, the most valuable and reusable modules will be selected for reconfiguration so that they can be easily accessed and disassembled. A hard disk drive is used as a case study to illustrate the method.
A Reactive Inelasticity Theoretical Framework for Modeling Viscoelasticity, Plastic Deformation, and Damage in Fibrous Soft Tissue
Authors: Safa Babak N. , Santare Michael H. , Elliott Dawn M.
Published: September 2018

Fibrous soft tissues are biopolymeric materials that are made of extracellular proteins, such as different types of collagen and proteoglycans, and have a high water content. These tissues have nonlinear, anisotropic, and inelastic mechanical behaviors that are often categorized into viscoelastic behavior, plastic deformation, and damage. While tissue's elastic and viscoelastic mechanical properties have been measured for decades, there is no comprehensive theoretical framework for modeling inelastic behaviors of these tissues that is based on their structure. To model the three major inelastic mechanical behaviors of tissue's fibrous matrix, we formulated a structurally inspired continuum mechanics framework based on the energy of molecular bonds that break and reform in response to external loading (reactive bonds). In this framework, we employed the theory of internal state variables (ISV) and kinetics of molecular bonds. The number fraction of bonds, their reference deformation gradient, and damage parameter were used as state variables that allowed for consistent modeling of all three of the inelastic behaviors of tissue by using the same sets of constitutive relations. Several numerical examples are provided that address practical problems in tissue mechanics, including the difference between plastic deformation and damage. This model can be used to identify relationships between tissue's mechanical response to external loading and its biopolymeric structure.
A Review of High-Speed Electro-Hydrostatic Actuator Pumps in Aerospace Applications: Challenges and Solutions
Authors: Chao Qun , Zhang Junhui , Xu Bing , Huang Hsinpu , Pan Min
Published: September 2018

The continued development of electro-hydrostatic actuators (EHAs) in aerospace applications has put forward an increasing demand upon EHA pumps for their high power density. Besides raising the delivery pressure, increasing the rotational speed is another effective way to achieve high power density of the pump, especially when the delivery pressure is limited by the strength of materials. However, high-speed operating conditions can lead to several challenges to the pump design. This paper reviews the current challenges including the cavitation, flow and pressure ripples, tilting motion of rotating group and heat problem, associated with a high-speed rotation. In addition, potential solutions to the challenges are summarized, and their advantages and limitations are analyzed in detail. Finally, future research trends in EHA pumps are suggested. It is hoped that this review can provide a full understanding of the speed limitations for EHA pumps and offer possible solutions to overcome them.
A Gear Load Distribution Model for a Planetary Gear Set With a Flexible Ring Gear Having External Splines
Authors: Hu Yong , Talbot David , Kahraman Ahmet
Published: September 2018

In order to accurately predict ring gear deformations and to investigate the effects of ring gear flexibility on quasi-static behaviors of planetary gear sets, a complete load distribution model of planetary gear sets having flexible ring gears will be formulated here based on the baseline model proposed by the same authors (Hu, Y., Talbot, D., and Kahraman, A., 2018, “A Load Distribution Model for Planetary Gear Sets,” ASME J. Mech. Des., 140(5), p. 053302). Direct comparisons to published experiments are provided to assess the accuracy of the proposed load distribution methodology. Example analyses with flexible ring gear rims are performed indicating that ring gear flexibility could influence gear mesh-level and planetary gear set system-level behaviors. Influence of spline supporting a ring gear is also investigated revealing that positions of planet branches with respect to external splines could influence ring deflections and resultant gear mesh load distributions.
Identifying Critical Design Parameters for Improved Body Temperature Measurements: A Clinical Study Comparing Transient and Predicted Temperature Measurements
Authors: Vesnovsky Oleg , Zhu Liang , Grossman Laurence W. , Casamento Jon P. , Chamani Alireza , Wijekoon Nadeesri , Timmie Topoleski L. D.
Published: September 2018

Readily available store brand, or “home,” thermometers are used countless times in the home and clinic as a first diagnostic measure of body temperature. Measurement inaccuracies may lead to unnecessary medical visits or medication (false positives), or, potentially worse, lack of intervention when a person is truly sick (false negatives). A critical first step in the design process is to determine the shortcomings of the existing designs. For this project, we evaluated the accuracy of three currently available store brand thermometers in a pediatric population. The accuracies of the thermometers were assessed by comparing their body temperature predictions to those measured by a specially designed and calibrated and fast-responding reference thermometer. The reference thermometer was placed at the measurement site simultaneously with the store brand thermometer and recorded the temperature at the measurement site continuously. More than 300 healthy or sick pediatric subjects were enrolled in this study. Temperatures were measured at both the oral and axillary (under the arm) sites. The store brand thermometer measurements characteristically deviated from the reference thermometer temperature after 120 s, and the deviations did not follow a consistent pattern. The Brand C thermometers had the greatest deviations of up to 3.7 °F (2.1 °C), while the Brand A thermometers had the lowest deviations; however, they still deviated by up to 1.9 °F (1.1 °C). The data showed that the tested store brand thermometers had lower accuracy than the ±0.2 °F (0.1 °C) indicated in their Instructions for Use. Our recorded reference (transient) data showed that there was a wide variation in the transient temperature profiles. The store brand thermometers tested stated in their documentation that they are able to predict a body temperature based on transient temperature values over the first 5–10 s of measurements, implying that they use an embedded algorithm to extrapolate to the steady-state temperature. Significant deviations from the maximum temperature after time t = 4.6t0.63 illustrated that the transient temperature profiles may not be represented by an exponential function with a single time constant, t0.63. The accuracy of those embedded algorithms was not confirmed by our study, since the predicted body temperatures do not capture the large variations observed over the initial 10 s of the measurements. A thermometer with an error of several degrees Fahrenheit may result in a false positive or negative diagnosis of fever in children. The transient temperature measurements from our clinical study represent unique and critical data for helping to design the next generation of readily available, highly accurate, home thermometers.
Novel Experimental Study of Fabric Drying Using Direct-Contact Ultrasonic Vibration
Authors: Patel Viral K. , Kyle Reed Frederick , Kisner Roger , Peng Chang , Moghaddam Saeed , Mehdizadeh Momen Ayyoub
Published: September 2018

Fabric drying is an energy-intensive process, which generally involves blowing hot dry air across tumbling wet fabric to facilitate evaporation and moisture removal. Most of the energy supplied is used to overcome the enthalpy of vaporization for water. Although this process tends to be inefficient, it is fairly simple and forms the basis for the majority of existing clothes dryer technology today. To address the relatively low efficiency, a new method of drying called “direct contact ultrasonic fabric drying” is proposed. The process involves using high-frequency vibration introduced by piezoelectric transducers, which are in contact with wet fabric. The vibration is used to extract water droplets from the fabric mechanically. In this study, a total of 24 individual transducers are used in a module to dry a 142 cm2 sized fabric. The performance characterization of this single module has enabled successful scale-up of the system to a midscale prototype dryer, which can be used to ultrasonically dry clothing-sized fabric (∼750 cm2). The first-generation ultrasonic fabric dryer fabricated uses as little as 17% of the energy needed by traditional evaporation-based drying techniques. In addition to experimental data, this paper presents the results of a kinetic and scaling analysis that provides some important insights into ultrasonic drying.
Flow Structure and Heat Transfer Characteristics of a Rectangular Channel With Pin Fins and Dimples With Different Shapes
Authors: Luo Lei , Yan Han , Du Wei , Wang Songtao , Li Changhai , Zhang Xinghong
Published: September 2018

In this study, numerical simulations are conducted to investigate the effects of pin fin and dimple shape on the flow structure and heat transfer characteristics in a rectangular channel. The studied shapes for dimple and pin fin are circular, spanwise-elliptical, and streamwise-elliptical, respectively. The flow structure, friction factor, and heat transfer performance are obtained and analyzed with Reynolds number ranging from 10,000 to 50,000. Channel with circular pin fin and dimple is chosen as the Baseline. Channels with spanwise-elliptical pin fins have the best heat transfer augmentation, while also accompanied with the largest friction factor. Spanwise-elliptical pin fin generates the strongest horseshoe vortex which is responsible for the best heat transfer augmentation. Besides, channels with streamwise-elliptical pin fins show the worst heat transfer augmentation and the smallest friction factors. Dimple plays an important role in improving the heat transfer. Spanwise-elliptical dimple yields the best heat transfer augmentation which is attributed to the strongest counter-rotating vortex, while streamwise-elliptical dimple shows the worst heat transfer enhancement.