bluuebunny/crossref_metadata_2025 huggingface dataset:
Mapping of instruments in Japanese for measuring evidence‐based practice among clinical nurses: A scoping review
Authors: Tomotaki Ai , Morioka Noriko , Tsuda Yasunobu
Published: July 2022

Aims

This work aims to map instruments available in Japanese that have been assessed for reliability or validity for measuring evidence‐based practice (EBP) among clinical nurses.

Background

As EBP competencies comprise various domains, many EBP instruments have been developed. However, instruments available in Japanese for measuring EBP have not been reported systematically.

Design

We conducted a scoping review.

Data sources

Two different bibliography databases were searched to identify EBP instruments published until 2019: ICHUSHI (for Japanese articles) and PubMed.

Review methods

After relevant studies were screened and identified, study profile characteristics were extracted to identify EBP instruments in Japanese, and the quality of methodology for developing such instruments was evaluated. This information was recorded and the characteristics were descriptively summarized.

Results

Ninety potentially relevant articles were identified, of which seven articles and nine instruments were included in this review. All instruments were based on self‐reported self‐efficacy and attitudes. Few Japanese instruments included all the steps required for EBP. The overall reporting quality of each instrument was low.

Conclusions

EBP instruments available in Japanese are extremely scarce. The study results show that it is difficult to measure the various aspects of EBP with the existing instruments.
Demand information sharing of fresh produce supply chain considering competing suppliers’ freshness‐keeping effort
Authors: Chen Zhenjiang , Dan Bin , Ma Songxuan , Tian Yu
Published: July 2022

This paper considers a fresh produce supply chain in which a retailer sources alternative produce from two competing suppliers. The suppliers make efforts to preserve product freshness, while the retailer, with demand forecast information, can share it with none, one or both of the suppliers strategically. By constructing a multistage game model, the optimal demand information sharing strategy in the supply chain is explored. The results show that the retailer has the willingness to disclose demand information only when the freshness elasticity is high. Significantly, with the improvement of the freshness elasticity, the retailer will transform from sharing information with both suppliers to one supplier. The suppliers are always willing to accept the information disclosed by the retailer. However, complete transparency of demand information may hurt the supply chain under certain conditions. To improve the supply chain performance, the retailer can charge both suppliers for information fees and adjust from sharing information with no suppliers to both suppliers with a relatively low freshness elasticity. Conversely, the retailer can change from sharing information with both suppliers to sharing information with one supplier through a charging contract with a relatively high freshness elasticity.
Oral characteristics in adult individuals with periodontal Ehlers‐Danlos syndrome
Authors: Lepperdinger Ulrike , Angwin Chloe , Milnes Di , Sobey Glenda , Ghali Neeti , Johnson Diana , Brady Angela F. , Kammin Tammy , Bowen Jessica M. , Gröbner Rebekka , Lundberg Pernilla , Scott James , Zschocke Johannes , van Dijk Fleur S. , Kapferer‐Seebacher Ines
Published: July 2022

Aim

Periodontal Ehlers‐Danlos syndrome (pEDS) is a monogenic type of Ehlers‐Danlos syndrome characterized by periodontal destruction at a young age. The present study aimed to document the oral phenotype of pEDS based on prospective clinical investigations.

Materials and Methods

Thirty‐five adult individuals from 13 families with a clinically and genetically confirmed diagnosis of pEDS underwent a systematic oral assessment.

Results

Periodontitis stage 3 or 4 or edentulism due to periodontal destruction were diagnosed in 94% of the individuals. First permanent tooth loss was reported at the age of 21.5 years (median; range 13–43 years). Deep periodontal pockets were infrequent, with 94% measuring <4 mm. However, there was increased clinical attachment loss (CAL) averaging 8 mm (range 4–13 mm), and the probability of being edentate between the age of 35 and 44 years was 28–47% compared with less than 0.25% of the general population. Radiographic anomalous findings were only found in a portion of subjects and consisted of fused roots of maxillary second molars (81%), root hypoplasia (57%), taurodontism (26%) and tooth rotation of premolars (67%). As such, radiographic findings are not considered common characteristics of pEDS.

Conclusions

Characteristic oral traits of pEDS in adults are severe CAL with shallow probing depths and marked gingival recession. This is complemented by a lack of attached gingiva. These indications need to be paralleled by genetic analyses to diagnose pEDS unambiguously.
Comparative analysis of bacterial communities in olive psyllids, Euphyllura straminea and Euphyllura pakistanica expose proteobacteria dominance
Authors: Fami‐Tafreshi Tahereh , Askarianzadeh Alireza , Saeedizadeh Ayatolla , Karamipour Naeime , Mehrabadi Mohammad
Published: July 2022

Insect–bacteria symbiont associations can be found in almost all insect orders which supply an array of physiological and ecological benefits to the host insect. Plant sap‐feeding insects, including psyllids, have developed symbiotic relationships with a variety of bacteria to compensate nitrogen‐poor diets. In this study, we determined the bacterial composition of two olive psyllid pest species, Euphyllura straminea and Euphyllura pakistanica (Hemiptera: Aphalaridae), using 16S rRNA gene sequence and qPCR analyses. Proteobacteria, including Alphaproteobacteria, Gammaproteobacteria and Betaproteobacteria, composed the primary bacterial structures of the psyllids. Alphaproteobacteria were the dominant bacterial group in E. straminea, while Gammaproteobacteria composed the main portion of the bacterial structure in E. pakistanica. The primary endosymbiont, Carsonella, was detected in both psyllids and Arsenophonus with high prevalence was the main secondary endosymbiont. Interestingly, we observed high titres of Wolbachia in E. straminea compared with E. pakistanica, which revealed a negative correlation between Wolbachia and Carsonella and Arsenophonus titres. Our results show that the limited core microbiota of olive psyllids is similar while the abundance of each bacterial symbiont can vary in different species. A possible role of Wolbachia in modulating bacterial composition in the psyllids was also suggested. There is the potential to utilize symbionts for developing pest control strategies by reducing the insect host's fitness such as targeting essential endosymbionts, transferring symbionts between species and parthenogenesis. Our results can be used as a basis for further research towards the implementation of novel strategies in symbiont‐based biological control of the olive psyllids.
Development and characterization of monoclonal antibodies specific for cyprinid herpesvirus 2
Authors: Zhao Lupin , Gao Wa , zheng Yihua , Lu Liqun , Li Qiang , Jiang Yousheng
Published: July 2022

Infections of Cyprinid herpesvirus 2 in goldfish and farmed crucian carp (Carassius auratus gibelio) are still an urgent problem worldwide. Detection and prevention are necessary for the control of haematopoietic necrosis disease caused by CyHV‐2. Although many sensitive molecular diagnostic methods have been developed, effective immunodiagnosis and neutralization approaches based on monoclonal antibodies (MAbs) against CyHV‐2 are still important to CyHV‐2 study. In this experiment, purified CyHV‐2 was used as antigens to produce monoclonal antibodies (Mabs). Six Mabs bound to different proteins were selected by Dot‐blot screening and Western‐blot analysis, and no one had cross‐reactivity with closely related koi herpesvirus. Among them, Mabs 2E1‐B10, 1F5‐A3 and 4C4‐A7 belonged to IgG1 isotype, while other three Mabs 3G9‐B11, 3B4‐G5 and 4F4‐B7 belonged to IgM isotype. These six Mabs all could specifically detect CyHV‐2 in CyHV‐2 infected caudal fin of Carassius auratus gibelio (GiCF) cells by immunofluorescence assays. Then, the neutralization ability was tested in vitro, and the result showed that all six Mabs can attenuate CPE by CyHV‐2 in vitro among which 2E1‐B10 had the best neutralization ability. The virus proteins recognized by these six Mabs were identified by mass spectrometry identification, and the result showed they probably were ORF88, ORF55R, ORF115 and ORF151R. This study is the first to prepare Mabs by purifying CyHV‐2, which will provide a practical basis for the in‐depth study of CyHV‐2 virus.
Improving salt diffusion by ultrasound application during wet salting of pork meat: A mathematical modeling approach
Authors: Sanches Marcio Augusto Ribeiro , Lapinskas Nicholas Matheus , Barretto Tiago Luis , da Silva‐Barretto Andrea Carla , Telis‐Romero Javier
Published: July 2022

The objectives of this research were to evaluate the influence of ultrasound (US; power of 600 W; frequency of 20 kHz), and salt concentration (SC) in brine (50 and 100 g of salt·L−1 of water) on salt gain (SG) in salted pork meat and to investigate the applicability of mathematical models to simulate SG. Four treatments were tested: T50SB, static brine with 50 g of salt·L−1 of water; T100SB, static brine with 100 g of salt·L−1 of water; T50US, US‐assisted brine with 50 g of salt·L−1 of water; T100US, US‐assisted brine with 100 g of salt·L−1 of water. After wet salting, the NaCl content was determined by the Mohr method. Five mathematical models (Azuara; Z and L; Simplified Fick Equation; Weibull; Diffusive) were tested to describe SG. US‐assisted brine and increasing SC in the brine increased (p < .05) the NaCl content in the salted meat. The salt diffusion coefficients also increased (p < .05) as a result of the increase in the SC in the brine and by the application of US (TM). All models tested showed predictability of experimental data and confirmed that US accelerated the SG during wet salting. The Azuara model presented the highest coefficients of determination (R2) and was chosen to predict the experimental data due to its best fit and because it has a simple mathematical solution, also enabling the prediction of equilibrium conditions. Therefore, US‐assisted brine is a technology that can shorten the salting time and improve the salt diffusion in pork meat and the Azuara model can be used to simulate wet salting processes.

Practical Applications

Ultrasound is an emerging technology that has shown promising results in the processing of meat and meat products. This study showed that ultrasound‐assisted brine of pork meat improves SG, increasing the salt diffusion coefficient in salted meat. Therefore, ultrasound‐assisted brine has the potential to shorten salting time in the industrial processing of pork meat. The Azuara model successfully described the kinetic parameters of the process and can be used to simulate the static and ultrasound‐assisted brine process.
Nipple ulcers of the nipple retractor technique to correct inverted nipples: A retrospective multivariate analysis
Authors: Cao Hairu , Wang Hayson Chenyu , Ting Wenyun
Published: July 2022

Background

A simple procedure using a nipple retractor to correct inverted nipples has been applied in clinical practice with stable and satisfactory aesthetic outcomes. Nipple ulceration and necrosis are rare and severe, with the causes unclear.

Objective

This study aimed to investigate the risk factors for the development of nipple ulcers in the nipple retractor technique.

Methods

A retrospective study was conducted on inverted nipple patients between January 2012 and September 2021. Clinical information, including baseline patient demographics, reproductive history, smoking, previous treatment, nipple inversion grades, nipple size, areola size, blood flow perfusion, and ulcer development, was collected.

Results

Twenty‐five female patients with 44 inverted nipples were enrolled. Nipple ulcers were present in seven patients, four of whom were bilateral. Logistic regression analysis showed nipple inversion grades (Z = 2.105, OR 7.005, 95% CI: 1.144–42.898, p = 0.035) and relative perfusion of nipples (Z = −2.337, OR 0.969, 95% CI: 0.944–0.995, p = 0.019) were significantly associated with ulceration. The structural equation model demonstrated the interaction of related factors: nipple inversion grades increased by 0.411 points for ulcers (p = 0.004), while relative perfusion of nipples decreased by 0.647 points for ulcers (p < 0.001).

Conclusion

Preoperative nipple inversion severity and post‐operative nipple blood supply may be the risk factors for nipple ulcer development in the nipple retractor technique.
Trauma exposure and short‐term volitional personality trait change
Authors: Blackie Laura E. R. , Hudson Nathan W.
Published: July 2022

Objective

Research into post‐traumatic growth (PTG) finds individuals report positive changes in their identity, relationships, and worldviews after trauma. In a pre‐registered 16‐week longitudinal study, we examined trait change after recent trauma exposure to test an operationalization of PTG as positive personality change. We examined the influence of intrapersonal and social factors including motivation to change traits, perceived social support, and event centrality.

Method

Participants (n = 1004) reported on trauma exposure in past 1‐month, centrality of each traumatic event, and social support. Participants with trauma exposure (n = 146) and a matched control group reported on their traits in 8 waves at 2‐week intervals, and motivation to change traits in 3 waves.

Results

Although some trait change was observed, it was not consistent with PTG. We found agreeableness declined in the trauma relative to the control group among participants who did not want to change in this trait. Conscientiousness declined for individuals with highly central traumas. Social support predicted increases in emotional stability, conscientiousness, and openness but only for individuals in the control group.

Conclusions

We discuss the value of defining PTG as positive trait change and suggest future directions including assessment of facet‐level changes and ideographic methods.
Evaluation of symmetric dimethylarginine in cats with acute kidney injury and chronic kidney disease
Authors: Loane Samantha C. , Thomson James M. , Williams Timothy L. , McCallum Katie E.
Published: July 2022

Background

Serum symmetric dimethylarginine (SDMA) concentrations are considered a biomarker for renal dysfunction in dogs and humans with acute kidney injury (AKI). No studies have assessed SDMA in cats with AKI.

Hypothesis/Objectives

SDMA correctly identifies cats with azotemic AKI.

Animals

Fifteen control cats, 22 with novel AKI, 13 with acute on chronic‐AKI (AoC) and 19 with chronic kidney disease (CKD).

Methods

Retrospective study. Cats with azotemia (serum creatinine concentrations >1.7 mg/dL) were defined as having AKI or CKD based on history, clinical signs, clinicopathological findings and diagnostic imaging, and classified using the International Renal Interest Society (IRIS) grading/staging systems. Serum SDMA concentrations were compared between groups with nonparametric methods, and correlations assessed using Spearman's correlation coefficient. Data are presented as median [range].

Results

SDMA concentrations were 11 (8‐21) μg/dL, 36 (9‐170)μg/dL, 33 (22‐75) μg/dL and 25 (12‐69) μg/dL in control, novel AKI, AoC and CKD cats. SDMA concentrations were significantly higher in cats with novel AKI (P < .001), AoC (P < .001) and CKD (P < .01) compared to controls. SDMA concentrations were significantly higher in cats with more advanced AKI (IRIS grade IV‐V) compared to less severe AKI (IRIS grade II). Serum creatinine and SDMA concentrations had a significant correlation in cats with novel AKI (rs = 0.826, n = 22; P < .001) and a significant correlation when all cats across all 4 groups were considered together (rs = 0.837, n = 69; P < .001).

Conclusions and Clinical Importance

Serum SDMA concentrations are elevated in cats with established AKI (novel and AoC) and CKD, providing evidence for use of SDMA as a biomarker for AKI in cats.
Impact of routine reporting of estimated glomerular filtration rate using the European Kidney Function Consortium and Chronic Kidney Disease Epidemiology Collaboration equations in a Western Australian community population
Authors: Napier Kathryn , Lim David , Thomas Elizabeth , Boyd James , Chakera Aron , Williamson James , Betts Kim , Manuel Justin , Tuando Teodulo Rey , Robinson Suzanne
Published: July 2022

Aim

In 2020, the European Kidney Function Consortium (EKFC) published a new creatinine‐based equation to estimate glomerular filtration rate (eGFR) to overcome known limitations in existing equations. The aim of this study is to model the potential impact on service referral and health expenditure of routine reporting of eGFR using the EKFC equation as compared to the CKD‐EPI equation in a Western Australian population.

Methods

eGFR was calculated for 760 614 patients with 2 368 234 creatinine results using the CKD‐EPI and EKFC formulas. Patients were grouped into a CKD cohort if they had at least two eGFR results of <60 ml/min/1.73 m2 from tests at least 90 days apart. The impact of each equation on the reclassification of CKD stages, CKD cohort classification, the rate of change in eGFR and direct health costs were assessed.

Results

About 90.66% of patients had a lower eGFR when calculated using the EKFC equation. About 12.6% of individuals were classified into a different CKD stage using the EKFC equation with 97.43% of these patients classified into a higher (more advanced) stage. There was a 25.9% increase in the number of patients identified as having CKD when calculated using the EKFC equation. Direct health costs also increased with the use of EKFC reporting.

Conclusion

Use of the EKFC equation will increase population prevalence of CKD and will result in a shift to higher stages of CKD. This has implications for monitoring and referral of patients within specialist services and has the potential to increase the need for multidisciplinary care.
Impact of claudin‐10 deficiency on amelogenesis: Lesson from a HELIX tooth
Authors: Obtel Nicolas , Le Cabec Adeline , Nguyen Thè Nghia , Giabicani Eloise , Van Malderen Stijn J. M. , Garrevoet Jan , Percot Aline , Paris Céline , Dean Christopher , Hadj‐Rabia Smail , Houillier Pascal , Breiderhoff Tilman , Bardet Claire , Coradin Thibaud , Ramirez Rozzi Fernando , Chaussain Catherine
Published: July 2022

In epithelia, claudin proteins are important components of the tight junctions as they determine the permeability and specificity to ions of the paracellular pathway. Mutations in CLDN10 cause the rare autosomal recessive HELIX syndrome (Hypohidrosis, Electrolyte imbalance, Lacrimal gland dysfunction, Ichthyosis, and Xerostomia), in which patients display severe enamel wear. Here, we assess whether this enamel wear is caused by an innate fragility directly related to claudin‐10 deficiency in addition to xerostomia. A third molar collected from a female HELIX patient was analyzed by a combination of microanatomical and physicochemical approaches (i.e., electron microscopy, elemental mapping, Raman microspectroscopy, and synchrotron‐based X‐ray fluorescence). The enamel morphology, formation time, organization, and microstructure appeared to be within the natural variability. However, we identified accentuated strontium variations within the HELIX enamel, with alternating enrichments and depletions following the direction of the periodical striae of Retzius. These markings were also present in dentin. These data suggest that the enamel wear associated with HELIX may not be related to a disruption of enamel microstructure but rather to xerostomia. However, the occurrence of events of strontium variations within dental tissues might indicate repeated episodes of worsening of the renal dysfunction that may require further investigations.
Red Wine Inspired Chromophores as Photodynamic Therapy Sensitizers†
Authors: Martins Lucas M. O. S. , Wang Xuhui , Silva Gustavo T. M. , Junqueira Helena C. , Fornaciari Bárbara , Lopes Lohanna F. , Silva Cassio P. , Zhou Peng , Cavalcante Victor F. , Baptista Mauricio S. , Quina Frank H.
Published: July 2022

Hydroxypyranoflavylium (HPF) cations are synthetic analogs possessing the same basic chromophore as the pyranoanthocyanins that form during the maturation of red wine. HPF cations absorb strongly in the visible spectral region, and most are fluorescent, triplet‐sensitize singlet oxygen formation in solution and are strong photooxidants, properties that are desirable in a sensitizer for photodynamic therapy (PDT). The results of this study demonstrate that several simple HPF dyes can indeed function as PDT sensitizers. Of the eight HPF cations investigated in this work, four were phototoxic to a human cervical adenocarcinoma cell line (HeLa) at the 1–10 μmol dm−3 level, while only one of the eight compounds showed noticeable cytotoxicity in the dark. Neither a Type I nor a Type II mechanism can adequately rationalize the differences in phototoxicity of the compounds. Colocalization experiments with the most phototoxic compound demonstrated the affinity of the dye for both the mitochondria and lysosomes of HeLa cells. The fact that relatively modest structural differences, e.g., the exchange of an electron‐donating substituent for an electron‐withdrawing substituent, can cause profound differences in the phototoxicity, together with the relatively facile synthesis of substituted HPF cations, makes them interesting candidates for further evaluation as PDT sensitizers.
Development and validation of a nursing home mortality index to identify nursing home residents nearing the end of life in dental clinics
Authors: Chen Xi , Caplan Daniel J. , Comnick Carissa L. , Hartshorn Jennifer , Shuman Stephen K , Xie Xian‐Jin
Published: July 2022

Background

Nursing home (NH) residents seek care at dental offices, yet many of them are at the end of life. The uncertain life expectancy further complicates the care of NH residents. This study aimed to develop and validate a Nursing Home Mortality Index (NHMI) to identify NH residents in the last year of life.

Methods

Logistic modeling was used to develop predictive models for death within 1 year after initial appointment by utilizing the new patient examination data and mortality data of 903 Minnesota NH residents. The final model was selected based on areas under the curve (AUC) and then validated using data from 586 Iowa NH residents. Based on the final model, the NHMI was developed with the estimated 1‐year mortality for the low, medium and high risk group.

Results

One‐year mortalities were 21% and 26% in the development and validation cohorts, respectively. Predictors included age, gender, communication capacity, physical mobility, congestive heart failure, peripheral vascular disease, cancer, cerebrovascular disease, chronic renal disease and liver disease. AUCs for the development and validation models were 0.73 and 0.68, respectively. For the validation cohort, the sensitivity and specificity were 0.79 and 0.53, respectively. The estimated 1‐year mortality risks for three risk groups were 0%–10%, 11%–19%, and ≥20%, respectively

Conclusion

The high mortality rate of NH residents following a dental exam highlighted a need to incorporate patients’ prognoses in treatment planning along with normative needs and patients’ preferences. The NHMI provides a practical way to guide treatment decisions for end‐of‐life NH residents.
YTGT: A new high‐prevalence antigen in the Yt blood group system in two unrelated Native Americans and transfusion management
Authors: Van Buren Nancy L. , Gillen Barbara , Lomas‐Francis Christine , Burgos Anna , Pease Daniel , Beaver Maria , Imbryk Adam , Dugger Julia , Fugate Alexandra , Hebel Eric , Lodermeier Michelle , Vege Sunitha , Westhoff Connie M.
Published: July 2022

Background

The Yt system consists of five antigens: antithetical Yta/Ytb and the high‐prevalence antigens YTEG, YTLI, and YTOT. We investigated a sample from a Native American (NA) female with post‐operative anemia and an unidentified antibody who developed rigors, tachycardia, and hypotension on transfusion of incompatible RBCs.

Methods and Materials

Serologic testing methods included LISS, PEG, and IgG gel. Test RBCs were treated with papain, trypsin, alpha‐chymotrypsin, 2‐amino‐ethylisothiouronium, and dithiothreitol. Rare RBCs were tested, and inhibition studies were performed. DNA extracted from WBCs was used for Sanger sequencing.

Results

Initial testing showed strong 3–4+ plasma reactivity with all panel cells at LISS IAT; auto control was negative. Positive reactions were observed with numerous rare RBCs except for PNH‐III, which lack GPI‐linked DO, Yt, CROM, JMH, and Emm. Enzyme sensitivity patterns suggest Yt specificity, and soluble recombinant srYt neutralized reactivity. ACHE sequencing revealed YT*A/A genotype but with a homozygous change in exon 2, c.290A>G (p.Gln97Arg). Antibody reactivity was reminiscent of that seen in an unrelated NA male investigated previously. His RBCs were nonreactive with her plasma. ACHE carried the same c.290G/G change.

Conclusion

Two unrelated NA patients were found to have an antibody to a new high‐prevalence Yt antigen, designated YTGT (YT6), associated with a clinically significant transfusion reaction. Identification of the specificity relied on enzyme sensitivity, use of PNH‐III RBCs, neutralization using soluble recombinant Yt, and the finding of a novel change in ACHE, c.290A>G (p.Gln97Arg), designated YT*01.‐06. IVIG and steroids were used to mitigate further reactions to transfusion.
Assessment of corneal and limbal epithelial thickness by spectral‐domain optical coherence tomography in brachycephalic and non‐brachycephalic dogs
Authors: Jeong Youngseok , Kang Seonmi , Ahn Junyeong , Kim Sol , Kim Hyelin , Park Jisoo , Seo Kangmoon
Published: July 2022

Objective

To investigate the variance in corneal epithelial thickness (CET) and limbal epithelial thickness (LET) according to the age and skull type by using spectral‐domain optical coherence tomography (SD‐OCT) in normal dogs.

Animals and procedures

This study used an eye each from 46 dogs (24 brachycephalic and 22 non‐brachycephalic dogs) assessed to have clear corneas. Each dog was classified according to age into groups 1 (0–5 years), 2 (6–10 years), and 3 (>11 years). OCT imaging was performed on the central cornea for CET and perpendicular to the quadrant of the limbus for LET. The average of the maximum LET (maxLET) value was measured in four eye quadrants.

Results

Corneal epithelial thickness was not significantly different according to age in brachycephalic and non‐brachycephalic dogs. Visualization of the limbal invagination was better when the maxLET was thick. Nasal and temporal maxLETs were significantly thicker than superior and inferior maxLETs in non‐brachycephalic dogs. In brachycephalic dogs, there was a significant decrease in nasal maxLET with age (rs = −0.489, p = .015). Significant differences between brachycephalic and non‐brachycephalic dogs were observed in nasal maxLET (p = .024) and temporal maxLET (p = .011).

Conclusions

Invagination was better visualized in the nasal and temporal limbal quadrants of non‐brachycephalic dogs compared with brachycephalic dogs, and the maxLETs of the regions were thicker than those of the brachycephalic dogs. CET and LET measurements using SD‐OCT can help in clinical assessment and research on ocular surface diseases in dogs.
A Clearanceometer for Determining Blade-Tip Clearances of Axial-Flow Compressors
Authors: Brunot A. W. , Fulton R. O.
Published: July 2022

This paper covers the design and use of an instrument for determining blade-tip clearances of axial-flow compressors. The development of the measuring head and control circuits for operating the probe-type head and the results obtained from the use of this instrument are covered with illustrations and graphs which show clearances in axial-flow compressors under various operating conditions.
A Study of Burner Oscillations of the Organ-Pipe Type
Authors: Putnam A. A. , Dennis W. R.
Published: July 2022

Three simplified combustion systems have been investigated for acoustical oscillations. The systems are: (a) a mixing chamber and multiple-port burner mounted in a combustion tube open at both ends; (b) a similar mixing chamber and multiple-port burner which completely blocked the secondary-air inlet of the combustion tube; and (c) a system similar to (b), but utilizing separate fuel and primary-air inlets, giving a diffusion flame rather than a premixed-gas flame. Oscillations were found to occur only for certain ranges of the variables. In the first system, the pitch differed significantly in adjacent ranges of oscillation. In the two latter systems, the frequency of the oscillations remained fairly uniform and close to the fundamental of the combustion tube, although breaks occurred in the data as the configurations of the inlet supply systems were varied. These results are explained on the basis of (a) the time of feedback of pressure pulses which ultimately cause changes in the heat-release rate, and (b) the location of the flame relative to a section of maximum pressure amplitude in the combustion tube. In further substantiation of the implications of the test results, the Appendix presents a thermodynamic treatment of the phase requirement between rate of heat release and pressure.
A Nondimensional Correlation of Flame Propagation at Subatmospheric Pressures
Authors: Cullen R. E.
Published: July 2022

The effect of ambient pressure on the propagation rate of Bunsen flames in propane-air and ethylene-air mixtures is described. It is concluded that the normal flame speed for the fuels studied varies inversely with the logarithm of the pressure from atmospheric pressures to as low as 1 in. Hg abs. A nondimensional parameter, the Peclet number, is established that correlates the results with four burner sizes, two fuels, and for the range of pressures investigated. It is concluded that the Peclet number must be kept large to avoid considerable reductions in flame speeds at subatmospheric pressures.
The Significance of the Thermal Number in Metal Machining
Authors: Chao B. T. , Trigger K. J.
Published: July 2022

The theoretical analysis of heat flow in conjunction with cutting data in high-speed orthogonal metal-machining operations reveals that, for a given tool rake, the temperature distribution along the shear plane is solely dependent on the thermal number, Vct/k. An explanation is offered for the difference in chip curvature as the cutting conditions are changed. Further significance of the thermal number in metal machining is presented.
A Sensitive Pressure Controller for High-Pressure Service
Authors: Golden P. L. , Headrick A. F.
Published: July 2022

An automatic, sensitive, pneumatic pressure controller has been developed for regulating the flow of hydrogen to a bench-scale, high-pressure, hydrogenation unit. It utilizes a 20-turn helical Bourdon tube which is connected to the flapper of a nozzle-flapper combination. When the nozzle is closed, air pressure in the controller acts through a system of bellows and cylinders on a rack which drives a gear connected to the regulating valve. The controller prevents slow drifts of pressure and has operated satisfactorily at 9000 psig pressure.
Rupture-Disk Design Evaluation and Bursting Tests
Authors: Prescott G. R.
Published: July 2022

The use of rupture disks as a quick-acting pressure-relief device in the chemical industry is well established. High-pressure synthesis units must be protected adequately against abnormal pressure surges caused by malfunctioning of equipment and chemical decompositions and reactions which may occur with explosive violence. The results of a recent investigation into the design and application of rupture disks at du Pont’s Belle Works in West Virginia constitute the basis of this paper.
Design and Application of Controlled-Volume Pumps for High Pressure in the Range of 10,000 to 30,000 Psi
Authors: Jones D. H.
Published: July 2022

Any thorough examination of current trends in process development should include consideration of the steady move toward higher operating pressures in various fields. Certain reactions which are favored at higher pressures are being investigated not only in the laboratory, but now are being expanded into semiworks and even into full commercial scale. Reactions formerly undertaken only at lower pressures are being developed for use at high pressures because of higher efficiencies and better yields. Equipment manufacturers certainly have felt the impact of this trend in that high-pressure specifications are definitely increasing. Controlled-volume pumps are required for many developments in this high-pressure field and this paper is an examination of their design and application in the range of 10,000 to 30,000 psi.
A Simple High-Speed Air Spinner for Centrifugal Testing of Small Mechanical Devices
Authors: Bild C. F. , Vial P. F.
Published: July 2022

This centrifuge was developed for the purpose of testing the functioning of mechanical and electromechanical devices while these devices were spinning up to 1000 rps. A typical device is a clock mechanism, in which parts of considerable mass shift position during test.
Plastic Flow in a Lead Extrusion
Authors: Yang C. T. , Thomsen E. G.
Published: July 2022

Commercially pure lead was extruded through a sharp-edged circular orifice by an indirect or inverted extrusion process. Metal flow directions and plastic strains were determined during a small stepwise deformation process from distorted, originally square, grid-line network scribed on a meridian plane. It was found that the metal flow directions do not coincide with instantaneous grid-line directions nor with the streamline directions in frictionless or potential fluid flow. It was further found that the metal located in the corner, formed by cylinder wall and die face, was in a state of plastic deformation. This observation is contrary to previously reported investigations and shows that the surface quality of the finished extrusion is dependent on the surface quality of the billet from which the extrusion was pressed. A strain analysis was made from which principal stress directions in the plastic metal were calculated.
Deformation Work Absorbed by the Workpiece During Metal Cutting
Authors: Thomsen E. G. , Lapsley J. T. , Grassi R. C.
Published: July 2022

The deformation work absorbed by the workpiece during metal cutting is analyzed. It was shown from photomicrographs that this is appreciable and may constitute the major energy absorbed in metal cutting when the depth of cut becomes small. The so-called “size effect in metal cutting,” in part, may be explained by this workpiece deformation. Correcting cutting forces for workpiece deformation in no way detracts from Merchant’s analysis, based on the minimum-energy principle. However, the criteria of plasticity in metal cutting and the correlation of metal-cutting data with tensile data remain in doubt.
Stress Relaxation in Compression of Rubber and Synthetic-Rubber Vulcanizates Immersed in Oil
Authors: Beatty J. R. , Juve A. E.
Published: July 2022

Stress relaxation in compression in air has been studied for compounds of various polymers. However, rubber seals, gaskets, and other applications are widely used where swelling agents, such as oil, are encountered. It was thought desirable to measure the stress-relaxation properties of various rubbers to determine their performance under such conditions. The results show that continuous stress relaxation is inhibited by the presence of oil and that unconfined swelling measurements predict the degree of inhibition directly. The variables of temperature and type of oil were investigated.
Effect of Preloading and Fatigue on Mechanical Properties of Glass-Cloth Plastic Laminates
Authors: Freas A. D.
Published: July 2022

Tensile tests of glass-cloth plastic laminates showed that modulus of elasticity and proportional-limit stress may be changed considerably after the first application of stress. A small number of preloads, in either tension or compression, have no appreciable effect on the strength of the laminate. The application of many repeated or reversed stresses, however, may result in a fatigue strength that is much lower than the static strength of the material.
The Rotary Regenerative Air Preheater for Gas Turbines
Authors: Bowden A. T. , Hryniszak W.
Published: July 2022

After some brief definitions, the paper deals with the influence of a regenerative air preheater on the performance of a simple open-cycle gas turbine, and formulas are given to show this influence, as well as the connection between the regenerator dimensions and the condition of minimum fuel consumption.
Some NACA Research on Centrifugal Compressors
Authors: Johnsen I. A. , Ginsburg Ambrose
Published: July 2022

This paper presents a summary of some of the results obtained in the NACA program of aerodynamic research on centrifugal compressors, including both theoretical and experimental aspects. The material presented is not intended to give specific design rules, but rather is intended to give some insight into the flow processes in centrifugal turbomachinery, to establish general trends of good design practice, and to indicate portions of the field that remain to be explored. The paper is arranged in three sections; (a) impeller research, (b) diffuser research, and (c) general aspects of application of centrifugal compressor to aircraft gas-turbine engines.
Optimum Three-Mode Controller Settings for Automatic Start-Up
Authors: Pessen D. W.
Published: July 2022

This paper presents a formula empirically derived from laboratory analog tests, which yields controller settings for a specific class of three-mode controllers. The controller settings specified by this formula will produce automatic start-up without overshooting, and, at the same time, provide close to optimum response to process load disturbances. Typical start-up and response curves obtained on an electric process analog by the use of this formula are presented. Finally, a rule of thumb is suggested, giving an indication of the maximum amount of dead time that can be tolerated in a process which must be started up automatically without overshooting.
Analogies for Hydraulic and Electric Drives in Servomechanisms
Authors: Chu Yaohan , Gould L. A.
Published: July 2022

The paper demonstrates the analogy between the d-c electric and hydraulic drives, commonly used in servomechanisms. This analogy is developed from their analogous basic relations, and their analogous methods of speed control are then shown. The analogous dynamic behavior of such servomechanisms is shown both in the derivation of the respective electric and hydraulic circuits and in the block diagrams. One distinguishing non-analogous character is that there is no hydraulic analogy to the mutual flux of electric machines. Nevertheless, it is shown that analogous dynamic behavior of the servo-mechanism resulting from an advantageous flux compounding in the electric drive can be achieved by applying certain pressure feedback in the hydraulic drive.
Laminar-Flow Forced Convection in Rectangular Tubes
Authors: Clark S. H. , Kays W. M.
Published: July 2022

The problem of laminar-flow heat transfer in tubes of rectangular and triangular cross section is considered. A numerical relaxation method is used to obtain minimum limiting Nusselt-number magnitudes to supplement the presently available data. Boundary conditions of both constant heat input per unit of length, and constant wall temperature are included. For the case of rectangular tubes sufficient points have been calculated so that interpolation of the limiting Nusselt numbers for any aspect ratio can be accomplished. Experimental data are presented for a square tube for both constant wall temperature and constant heat input, and for a rectangular tube, aspect ratio 2.62, for constant wall temperature. These data, together with the limiting Nusselt-number theory, provide a rational basis for estimation of entrance-length effects for rectangular tubes, and result in a correlation in the form, NNu = ϕ[NRNPr/(l/4rh)], applicable to the design of gas-flow heat exchangers.
Stress-Crazing of Plastics
Authors: Sauer J. A. , Hsiao C. C.
Published: July 2022

The effect of various factors on the inception and growth of crazing is reviewed and some of the similarities between crazing in plastics, exposure-cracking in rubber, and stress-cracking in metals are described. Various examples of stress-crazing in transparent plastics are presented and the stress-strain behavior reported for crazed, noncrazed, and oriented material. Rate of propagation of crazing also has been investigated. The test results indicate that penetration of crazing cracks in polystyrene can be represented over a limited stress range by a linear function of both time and stress magnitude. Some measures advocated for avoiding the undesirable effects of crazing include use of special coatings, annealing, and establishment of working stresses based on onset of crazing rather than on static fracture.
Some Design Considerations for Injection-Molding Heating Chambers
Authors: Gilmore G. D. , Thayer G. B.
Published: July 2022

The general design of injection-molding heating chambers has become established after gradual development through several years of experience. Some of the details of design which are directly concerned with the plastic-material characteristics have been examined to a limited extent. Very little engineering-design information has been available for a careful consideration of these details. Heat-transfer and pressure losses in the heating chamber are interrelated and the geometry of the passages through which the plastic moves can be arranged for optimum heat-transfer rate with minimum pressure loss. The available theoretical, experimental, and practical information concerning the behavior of plastic materials, under high pressures, in granular and fluid conditions is considered. This information is combined into a systematic approach to the geometrical problems of the design of injection-molding heating chambers.
Furnace Heat Absorption in a Spreader-Stoker-Fired Steam Generator: 2—Variation in Furnace Heat Absorption as Shown by Measurement of Temperature of Exposed Side of Furnace Tubes
Authors: Feeley F. G. , Miller E. C.
Published: July 2022

This is a report of test work performed under the auspices of the ASME Special Research Committee on Furnace Performance Factors, and covers the testing of a spreader-stoker-fired furnace. Previous test work was performed on three pulverized-coal-fired furnaces and one gas-fired furnace. In so far as possible the present test work followed the technique developed on the previous tests. Furnace heat absorption was determined by furnace heat balance and also by measuring the surface temperature of the exposed side of the furnace tubes. Part 2 of this paper covers the measurement of furnace heat absorption by the latter method. The test procedure required a series of tests to determine the stack dust loading. Because of the many questions received concerning the results of this portion of the test work the data have been included.
Measurement of Pulsating Flow With Propeller and Turbine-Type Meters
Authors: Dowdell R. B. , Liddle A. H.
Published: July 2022

Tests have been made on four different fluid meters under various conditions of unsteady flow. Results are presented, showing that in some cases accurate measurement of pulsating flow is possible.
Modern Trends in Hydraulic-Turbine Design in Europe
Authors: Bovet G. A.
Published: July 2022

This paper deals with modern trends in the design of hydraulic turbines in Europe, especially in so far as they differ from standard American practice. The paper describes and discusses the general arrangement of large hydrounits, the use of high-grade alloys, the efficiency tests of large turbines, various improvements in speed regulation, and departures from accepted practice in the field of gates and valves.
Pressure Surges at Large Pump Installations
Authors: Parmakian John
Published: July 2022

This paper describes the method of water-hammer analysis and control used in the design of the large pump installations at Grand Coulee, Granby, and Tracy Pumping Plants for the condition of power failure at the pump motors. It includes a summary of the major features of these installations and a comparison between the observed and computed water-hammer effects. Useful charts for obtaining the approximate water-hammer effects in any pump-discharge line resulting from power failure are also presented.
Corrosion of Mercury-Boiler Tubes During Combustion of a Heavy Residual Oil
Authors: Hall A. M. , Douglass D. , Jackson J. H.
Published: July 2022

Tube wastage in the mercury boiler at the South Meadow Station of the Hartford Electric Light Company became so serious after 3076 hours of operation that it was necessary to reduce the rating from its 15,000-kw capacity to 13,500 kw. On June 1, 1950, the company engaged Battelle Memorial Institute to study the problem. Two approaches were considered: (a) Reduction of tube wastage to an acceptable rate by covering the tubes with a suitable protective coating; and (b) reduction of the corrosiveness of the combustion products of the fuel to an acceptable level by making a special addition to the fuel. The test procedure and results are given in the paper.
Thermal Shock and Other Comparison Tests of Austenitic and Ferritic Steels for Main Steam Piping—A Summary Report
Authors: Stewart W. C. , Schreitz W. G.
Published: July 2022

Test results are summarized for thermal-shock specimens and mock-ups of ferritic and austenitic steels. In addition, complete test data are reported for a laboratory test program which was undertaken to supplement the full-scale tests. Thermal-shock tests of 6-in. pipe-and-valve assemblies in both 18-8 Cb and 2¼ Cr, 1 Mo materials are described. Specimens were of two weights, schedules 80 and 160. The 160-schedule thermal-shock specimens each contained a section of dissimilar pipe which introduced transition and composite welded joints. The shock treatment was designed to simulate the quenching action that might result from the carry-over of boiler water into a pipe line carrying steam at 1050 F temperature. The steam pressure for the 80-schedule specimens was 900 psi, and for the 160-schedule specimens, 2000 psi. Each assembly was subjected to 100 shocks. The effect of mechanical loading on full-scale members was investigated by testing mock-ups which were designed to simulate expansion bends. The report contains considerable high-temperature test data that were obtained for laboratory specimens. The specimens were taken from pipe and casting assemblies which were fabricated and heat-treated in the same manner as the full-scale test members. Results include tensile properties to 1100 F; and stress-rupture, creep, and fatigue properties at 1000 and 1100 F temperatures. Tests were also made of specimens taken from thermal-shock specimens and mock-ups.
Metal-Cutting Chatter and Its Elimination
Authors: Hahn R. S.
Published: July 2022

The practical problem of suppressing chatter in a machine tool often can be solved by a study of the modes of vibration and the proper application of dampers. Concerning the cause of chatter, three phenomena may be recognized: namely, primary chatter, transitional instability, and feedback effect. Primary chatter is believed to be caused by the lag of the temperature and stress state in the vicinity of the shear plane. Transitional instability is associated with a work-hardened skin and may occur whenever all or part of the cutting edge operates in this region. Constructive and destructive feedback effects are demonstrated and a method of utilizing these effects to suppress chatter is suggested.