bluuebunny/crossref_metadata_2025 huggingface dataset:
Nurse‐led telephone intervention for lifestyle changes on glycaemic control in people with prediabetes: Study protocol for a randomized controlled trial
Authors: Abbate Manuela , Fresneda Sergio , Yañez Aina , Ricci‐Cabello Ignacio , Galmes‐Panades Aina M , Aguilo Antoni , Bennasar‐Veny Miquel ,   the PREDIPHONE trial group
Published: March 2021

Aim

To evaluate the effectiveness of a nurse‐led personalized telephone lifestyle intervention versus automated SMSs in the reduction of fasting plasma glucose in adults with prediabetes.

Design

The PREDIPHONE is a randomized controlled, parallel, two arms, superiority trial with 15 months of follow‐up. Participants will be randomized to either the intervention group (teleconsultations) or the active control group (SMSs).

Methods

A total of 428 participants will be randomized in a 1:1 ratio to one of the two arms and followed up during 9 months. The teleconsultations group will receive nurse‐led personalized advice, while the SMSs group will receive 4–5 brief SMSs a week. Participants in both groups will receive evidence‐based recommendations for diet and physical activity (PA). Outcome measures will be collected at baseline, months 4 and 9 and at month 15, to evaluate post‐intervention effects.

Discussion

Prevention of diabetes through the implementation of lifestyle interventions remains an important priority. The current pandemic situation has magnified its urgency as it heavily affected the functionality of the healthcare system. Moreover, it created the need of remotely delivering preventative interventions. This study will provide insights on the effectiveness and feasibility of a telephone‐based intervention led by nurses in the amelioration of risk factors associated with diabetes.

Impact

Findings from this study will offer health services decision‐makers sound evidence regarding an alternative method to face‐to‐face consultations that could be practical, acceptable and inexpensive, and that concretely answers the need for easily implementable prevention strategies.

Trial Registration

NCT04735640 (ClinicalTrials.gov identifier).

Protocol version

V1.0, 18/02/2021.
Isovaleric acid ameliorates ovariectomy‐induced osteoporosis by inhibiting osteoclast differentiation
Authors: Cho Kwang Min , Kim Ye Seon , Lee Mingyu , Lee Ha Young , Bae Yoe‐Sik
Published: March 2021

Osteoclasts (OCs) play important roles in bone remodelling and contribute to bone loss by increasing bone resorption activity. Excessively activated OCs cause diverse bone disorders including osteoporosis. Isovaleric acid (IVA), also known as 3‐methylbutanoic acid is a 5‐carbon branched‐chain fatty acid (BCFA), which can be generated by bacterial fermentation of a leucine‐rich diet. Here, we find that IVA suppresses differentiation of bone marrow‐derived macrophages into OCs by RANKL. IVA inhibited the expression of OC‐related genes. IVA‐induced inhibitory effects on OC generation were attenuated by pertussis toxin but not by H89, suggesting a Gi‐coupled receptor‐dependent but protein kinase A‐independent response. Moreover, IVA stimulates AMPK phosphorylation, and treatment with an AMPK inhibitor blocks IVA‐induced inhibition of OC generation. In an ovariectomized mouse model, addition of IVA to the drinking water resulted in significant decrease of body weight gain and inhibited the expression of not only OC‐related genes but also fusogenic genes in the bone tissue. IVA exposure also blocked bone destruction and OC generation in the bone tissue of ovariectomized mice. Collectively, the results demonstrate that IVA is a novel bioactive BCFA that inhibits OC differentiation, suggesting that IVA can be considered a useful material to control osteoclast‐associated bone disorders, including osteoporosis.
The Production of Contemporary Sociological Knowledge in Hong Kong
Authors: Tang Denise Tse‐Shang
Published: March 2021

This paper explores the development of academic sociology in Hong Kong since the expansion of higher education and increased student enrolment in the nineties. Colleges gained university titles and sociology departments matured as a result. I attempt to trace the current state of sociology in teaching programs and research directions. I conclude with a discussion of future developments with specific reference to the repositioning of Hong Kong within sociology as the former British colony continue to negotiate, navigate and grapple its relationship with Mainland China both as a productive site for sociological research and a reference point to be different in method.
Different School Reopening Plans on Coronavirus Disease 2019 Case Growth Rates in the School Setting in the United States
Authors: Liu Dong , Lin Ge , Sun Xiaoting , Du Yi , Liu Han , Qu Ming
Published: March 2021

BACKGROUND

In fall 2020, all public K‐12 schools reopened in broadly 3 learning models. The hybrid model was considered a mid‐risk option compared with remote and in‐person learning models. The current study assesses school‐based coronavirus disease 2019 (COVID‐19) spread in the early fall using a national data set.

METHODS

We assess COVID‐19 case growth rates from August 10 to October 14, 2020 based on a crowdsourcing data set from the National Education Association. The study follows a retrospective cohort design with the baseline exposures being 3 teaching models: remote learning only, hybrid, and in‐person learning. To assess the consistency of our findings, we estimated the overall, as well as region‐specific (Northeast, Midwest, South, and West) and poverty‐specific (low, mid, and high) COVID‐19 case‐growth rates. In addition, we validated our study sample using another national sample survey data.

RESULTS

The baseline was from 617 school districts in 48 states, where 47% of school districts were in hybrid, 13% were in remote, and 40% were in‐person. Controlling for state‐level risk and rural‐urban difference, the case growth rates for remote and in‐person were lower than the hybrid (odds ratio [OR]: 0.963, 95% confidence interval [CI]: 0.960‐0.965 and OR: 0.986, 95% CI: 0.984‐0.988, respectively). A consistent result was found among school districts in all 4 regions and each poverty level.

CONCLUSIONS

Hybrid may not necessarily be the next logical option when transitioning from the remote to in‐person learning models due to its consistent higher case growth rates than the other 2 learning models.
The Relationship Between Physical Activity and School Success Among Children With and Without Special Health Care Needs
Authors: Kanda Deborah , Walker Ashley , Siekirk Nicholas , Colquitt Gavin
Published: March 2021

BACKGROUND

School‐environments are thought to be strong influences of behavioral choices. There is limited research available on the role of physical activity (PA) and school success among children with special health care needs (CSHCN). The purpose of this study was to explore differences in PA among CSHCN and non‐CSHCN and how the school success index is related to PA in both groups.

METHODS

Data were taken from new version of the National Survey of Children's Health (NSCH), which consolidated questions from the previous NSCH and the National Survey of Children with Special Health Care Needs (NS‐CSHCN). Chi‐square and logistic regression analyses were employed to examine group differences.

RESULTS

There were significant differences among both subgroups, although most school‐aged children did not meet recommended PA guidelines. Chi‐squared analyses indicated; school engagement and the parent's perception of child safety at school were associated with the likelihood of meeting PA guidelines. Logistic regression analyses showed that the odds of meeting PA guidelines were associated with the school success index.

CONCLUSIONS

Comprehensive school health programs should focus on PA both subgroups. School health educators should continue to advocate for safe and structured extracurricular activities to improve the child and adolescent's engagement and overall well‐being.
Evaluation of Preferences Among Students Participating in the US Department of Agriculture Fresh Fruit and Vegetable Program
Authors: Masis Natalie , McCaffrey Jennifer , Johnson Susan L. , Chapman‐Novakofski Karen
Published: March 2021

BACKGROUND

Improving children's fruit and vegetable (FV) preferences may be important as preferences can predict FV consumption. The purpose of this study was to evaluate FV preferences over time, with repeated experience, as part of the Fresh Fruit and Vegetable Program (FFVP).

METHODS

Fruits (F; N = 28) and vegetables (V; N = 29) were distributed twice a week, over 35 weeks, at a participating FFVP school (N = 236 students, 12 teachers, K‐2nd grade). Preference ratings using 3‐point Likert scale were analyzed over 35 weeks.

RESULTS

For 57 FVs rated for preference, ratings revealed that F had higher frequency of children choosing “I like it” than for V (78% F; 38.2% V; p < .05) and liking distribution was different between F and V (p < .001). Significant relations were found between liking and: (1) grade (r = −0.02, p = .02), and (2) time (r = −0.09, p < .001). Models indicated that V served (β = −0.40), timepoint (β = −0.07), and grade level (β = −0.02) accounted for significant variance for preference ratings (R2 = 0.17, p < .001), indicating that preference ratings declined over time.

CONCLUSIONS

Fruits were preferred over vegetables. Overall preference ratings were negatively impacted by time, grade level, and vegetables served. Being exposed one time to a variety of FVs did not improve ratings for vegetables.
MRIofCNSlymphoma with choroid plexus involvement in five dogs and one cat
Authors: Lampe R. , Levitin H. A. , Hecht S. , Vieson M. D. , Selting K. A. , Hague D. W. , Foss K. D.
Published: March 2021

Objectives

To describe the clinical features, magnetic resonance imaging (MRI) findings, and outcome of dogs and cats with central nervous system (CNS) lymphoma that involved the choroid plexus.

Materials and Methods

A bi‐institutional retrospective study of MRI of dogs and cats with CNS lymphoma, in which the choroid plexus was affected on MRI. Signalment, clinical, MRI, clinicopathologic and histopathologic findings were recorded and evaluated.

Results

CNS lymphoma with choroid plexus involvement on the MRI was identified in five dogs and one cat. MRI revealed diffuse enlargement and multifocal nodularity in the choroid plexus in most cases, with the fourth ventricle the most common site affected. Five of the cases had signs of extraneural involvement (including the cat), while the sixth case was not staged. Four of five CSF samples analysed provided a diagnosis of lymphoma.

Clinical Significance

We report MRI findings of CNS lymphoma involving the choroid plexus. These results show the importance of recognising novel imaging patterns and the potential utility of CSF collection in diagnosing CNS lymphoma involving the choroid plexus ante mortem.
Late onset recurrence of clinical signs after surgery for intervertebral disc extrusion in French bulldogs
Authors: Kerr S. , Crawford A. H. , De Decker S.
Published: March 2021

Objectives

To identify the prevalence of recurrence of clinical signs after initial successful decompressive surgery for intervertebral disc extrusion in French bulldogs.

Materials and Methods

A medical record search was performed to identify French bulldogs that experienced an initial successful outcome after surgery for thoracolumbar or cervical intervertebral disc extrusion. Collected information included signalment, neurological examination findings, intervertebral disc extrusion location, presence of vertebral malformations, kyphosis, type and extent of surgery. Decompressive surgery was not followed by extensive prophylactic fenestrations. Follow‐up information was retrieved from medical records and telephone interviews with referring veterinary surgeons.

Results

Eighty‐four French bulldogs with thoracolumbar (n=55) or cervical (n=29) intervertebral disc extrusion were included. Forty‐three (51%) dogs that had decompressive surgery for thoracolumbar (n=29) or cervical (n=14) intervertebral disc extrusion suffered recurrence of signs. The median time between decompressive surgery and recurrence of clinical signs was 9 months and 21 days. Of the 29 dogs suffering recurrence of clinical signs following surgery for thoracolumbar intervertebral disc extrusion, 24 returned for recurrence of clinical signs localised to the thoracolumbar segments, while five returned for recurrence of signs localised to the cervical region. Of the 14 dogs who suffered recurrence of signs following surgery for cervical intervertebral disc extrusion, nine returned for signs localised to the cervical region, while five returned for clinical signs localised to the thoracolumbar region.

Clinical Significance

This study suggests a high rate of late onset recurrence of clinical signs after decompressive surgery for intervertebral disc extrusion in French bulldogs. This information can aid in the management of owner expectations.
The appearance of canine insulinoma on dual phase computed tomographic angiography
Authors: Coss P. , Gilman O. , Warren‐Smith C. , Major A. C.
Published: March 2021

Objectives

To further evaluate the appearance of insulinoma in dogs on dual‐phase CT angiography, given the disparity of findings in recent publications. To establish whether CT angiographic localisation of insulinoma correlates with surgical findings.

Materials and Methods

Single centre study of dogs with a final diagnosis of insulinoma which underwent abdominal CT angiography. Scans were retrospectively re‐evaluated for specific features by two board‐certified veterinary radiologists. These findings were also subsequently compared to surgical and histopathological reports to determine the accuracy of lesion localisation on CT.

Results

Thirty‐five cases were included in final analysis, with pancreatic nodules identified in 33. Twenty‐one were confirmed as insulinoma with histopathology. Jack Russell Terriers were over‐represented. Twenty of 21 cases with confirmed insulinoma and 27 of 33 overall showed hyperattenuation in the arterial phase. The mean size of pancreatic insulinoma on CT was 15.1 mm, and 18.2% were larger than 20 mm. Eighteen of 21 confirmed and eight of 12 suspected insulinomas caused a deformation of the pancreatic shape, with two only identified as a result of this feature as these lesions were isoattenuating throughout the study. Pancreatic insulinoma location at surgery matched that described on the CT images in 17 of 19 cases where location was described in the surgical report.

Clinical Significance

In contrast to recent publications, this study suggests hyperattenuation of insulinomas in the arterial phase is a predominant feature, and that hypoattenuation or isoattenuation are much less common. CT angiography is accurate in prediction of lesion location before surgery in most cases.
Effect of telmisartan, angiotensin‐converting enzyme inhibition, or both, on proteinuria and blood pressure in dogs
Authors: Fowler Brittany L. , Stefanovski Darko , Hess Rebecka S. , McGonigle Kathryn
Published: March 2021

Background

The use of telmisartan (TEL), an angiotensin‐receptor blocker, for the control of systemic hypertension and proteinuria in dogs has not been reported extensively in a clinical setting.

Objectives

To determine the effects of an angiotensin‐converting enzyme inhibitor (ACEi) alone, ACEi in combination with TEL, or TEL alone on systolic blood pressure and proteinuria in dogs with protein losing nephropathy (PLN).

Animals

Forty‐two client‐owned dogs being treated for PLN.

Methods

Retrospective observational study of medical records of dogs at a university teaching hospital from 2012 to 2018 with the use of benazepril or enalapril alone, TEL alone, or both modalities for the management of PLN. Noninvasive blood pressure and urine protein to creatinine ratio (UPC) were compared among the treatment groups over time. A multivariable mixed‐effects linear regression model followed by post hoc analysis was used to estimate the marginal means and differences between the treatment groups.

Results

In comparison to group ACEi alone, combination treatment of an ACEi with TEL significantly reduced (P = .007) systolic blood pressure by 13 mm Hg (95% confidence interval [95% CI]: 4‐22 mm Hg). Angiotensin‐converting enzyme inhibitor + TEL in comparison to ACEi alone showed significant (P = .01) reduction in UPC of 2.5 (95% CI: 0.6‐4.4). The UPC of group ACEi + TEL was significantly lower (P = .01) in comparison to TEL alone by 3.8 (95% CI: 0.8‐6.8).

Conclusions and Clinical Importance

Telmisartan can be used to treat systemic hypertension and proteinuria in dogs.
Apatite halogen and hydrogen isotope constraints on the conditions of hydrothermal alteration in carbonaceous chondrites
Authors: Piralla Maxime , Tartèse Romain , Marrocchi Yves , Joy Katherine H.
Published: March 2021

Apatite has been widely used for assessing the volatile inventory and hydrothermal fluid compositions of asteroidal and planetary bodies. We report the OH, F, and Cl abundances, as well as the hydrogen isotope composition, of apatite in the CM1‐2 chondrite Boriskino and in the C1‐ungrouped Bench Crater meteorite. Apatite in both meteorites is halogen‐poor, close to the hydroxylapatite endmember composition, and characterized by average δDSMOW values of −226 ± 59% and 233 ± 92%, respectively. Compared to apatite, the matrix in Bench Crater is depleted in D with a δDSMOW value of −16 ± 119‰. Comparing apatite and water H isotope compositions yields similar apatite‐waterD/Hfractionation ΔDApatite‐Waterof approximately 120–150‰ for both chondrites, suggesting that apatite formed at similar temperatures. Combining a lattice strain partitioning model with apatite F and Cl abundances in Boriskino and Bench Crater yields low F and Cl abundances <300 μg g−1in apatite‐forming fluids, and fluid F/Cl ratios that are roughly consistent with the bulk F/Cl ratios of other CI and CM chondrites. This suggests that hydrothermal alteration on these meteorite parent bodies took place under closed‐system conditions. Based on the OH abundance estimates for the apatite‐forming fluids, we estimated the pH values of alteration fluids to be of approximately 10–13. Such alkaline fluid compositions are consistent with previous modeling and suggest that apatite formed late, toward the end of completion of hydrothermal alteration processes on the Boriskino and Bench Crater parent bodies.
A case report of a sialolith proving difficult to locate, with a sudden urgency to rule out a mucoepidermoid carcinoma
Authors: Sandhu Baljinder Kaur , Weir Justin , Devine Maria
Published: March 2021

Sialoliths arising extraductally are rarely reported, particularly when large in size. Here we report a large calcified mass presenting in the submandibular region which proved difficult to locate with imaging. Clinical presentation findings can include pain, swelling (usually associated with eating), obstruction of the salivary duct and sialadenitis. A 71‐year‐old male was referred by his general dental practitioner to the Oral Surgery department regarding a 6‐month history of a firm painful swelling in the left floor of mouth. He had experienced only one episode of associated submandibular swelling which resolved spontaneously after a few days. A large, mobile, firm mass was palpable on clinical examination in the left lingual sulcus, which was slightly tender. There was no associated swelling palpable of the submandibular gland. Ultrasound imaging confirmed a calcified mass present of 18 mm in anteroposterior (AP) dimension which was not related to the submandibular duct or gland. Following recommendation from the Radiologist, a small field computed tomography (CT) scan was requested to locate the mass and determine its relationship to adjacent structures. CT findings confirmed a heavy calcified mass replacing much of the sublingual gland, with the absence of submandibular sialadenitis or duct dilation. The report raised a query of mucoepidermoid carcinoma so prompt excision to confirm the diagnosis was arranged accordingly. The patient recovered well following extraductal excision of the sialolith and marsupialisation of the submandibular duct under general anaesthesia.
Localised oral amyloidosis in the context of oral epithelial dysplasia: Literature review and report of two cases
Authors: Dobson Marianne L. , Wright Alison L. , White Sharon J. , Macluskey Michaelina
Published: March 2021

Amyloidosis is a group of rare progressive diseases that occur as a result of abnormal protein folding and aggregation. Systemic amyloidosis is a serious disease with high mortality, and prompt diagnosis is key to improving prognosis. Conversely, localised amyloidosis does not reduce life expectancy and can often be treated with simple surgical excision. Amyloid deposits can be found in the oral cavity, usually in the context of systemic amyloidosis. We present two cases of localised oral acquired immunoglobulin light chain (AL) amyloidosis that were detected in oral biopsies taken for the management of oral epithelial dysplasia (OED). Both patients underwent thorough multisystem investigations by haematology in conjunction with the NHS National Amyloidosis Centre (NAC) in order to exclude systemic amyloidosis and confirm the diagnosis. Localised oral amyloidosis is rare, and to our knowledge, localised oral AL amyloidosis has not been reported in the context of OED before. We discuss important learning points from these cases as well as hypothesising on the pathophysiology involved.
Augmenting salt tolerance in rice by regulating uptake and tissue specific accumulation of Na+‐ through Ca2+‐induced alteration of biochemical events
Authors: Gupta A. , Shaw B. P.
Published: March 2021

The protective effect of Ca2+ against NaCl toxicity was investigated in two rice varieties with contrasting for salt tolerance to understand the mechanistic details of the antagonism to address adverse effects of salinity on agriculture.

The study primarily examined the influence of Ca2+ on expression/activity of the effectors and regulators involved in Na+ translocation.

Calcium reduced uptake of Na+ concomitant with higher tissue K+/Na+ in seedlings, comparatively more in salt‐tolerant Nona Bokra than in salt‐sensitive IR‐64, together with a significant increase in root PM H+ATPase in the former, but not in the latter. Increased antagonism in Nona Bokra could be the result of Ca2+ signalling‐mediated phosphorylation of PM H+ATPase in roots caused by a significant Ca2+‐dependent increase in expression of OsCIPK24, which did not occur in IR‐64. Furthermore, significant Ca2+‐mediated NaCl‐induced increase in transcription of 14‐3‐3 protein in Nona Bokra, but not in IR‐64, might also lead to a greater protective effect of Ca2+ in the former, as 14‐3‐3 protein is essential for activating PM H+ATPase.

Thus, efficient functioning of PM H+ATPase could be key in determining resistance of plants to salinity, implying that identification of the Ca2+‐dependent kinase phosphorylating the PM H+ATPase threonine residue and manipulation of its expression, together with expression of 14‐3‐3 proteins could be an important strategy to improve salt tolerance of crops and their cultivation in salt‐affected lands.
Recent development in ecdysone receptor of crustaceans: current knowledge and future applications in crustacean aquaculture
Authors: Abdullah‐Zawawi Muhammad‐Redha , Afiqah‐Aleng Nor , Ikhwanuddin Mhd , Sung Yeong Yik , Tola Siriporn , Fazhan Hanafiah , Waiho Khor
Published: March 2021

Ecdysone receptor (EcR) is the primary regulator of the ecdysteroid signalling pathway, a critical pathway that directly links to moulting. In addition, EcR also regulates growth, development, reproduction and regeneration in crustaceans. However, there remains a huge gap of knowledge between the detailed structure and functional role(s) of crustacean EcR compared to that of insects. Motif and phylogenetic analyses of publicly available crustacean EcR proteins revealed the evolutionary relationship of EcR in this subphylum and highlighted its conserved characteristics among crustaceans. The role of EcR in the regulation of essential physiological processes in crustaceans including moulting, chitin synthesis, general growth and development, gonadal and maturation, and limb regeneration was discussed based on the available literature. This essential moult‐related nuclear receptor could serve as a useful molecular indicator of moulting and gonadal maturation, as a potential target for pesticide production against parasitic crustacean species in the aquaculture industry, as well as valuable bioindicators of environmental stressors.
Skin hydration and transepidermal water loss after bathing compared between immersion and showering
Authors: Nitiyarom Rattanavalai , Anuntarumporn Lillada , Wisuthsarewong Wanee
Published: March 2021

Background

Various methods of bathing may affect skin properties differently.

Aims

To compare the effects of immersion and showering on skin hydration and transepidermal water loss (TEWL).

Method

This experimental study included healthy volunteers whose forearms were immersed and showered for 3 minutes. Skin hydration and TEWL were assessed serially before and after immersion and showering of volunteer forearms.

Results

Seventy‐eight healthy volunteers (49 females, 29 males) were enrolled with an age range of 12‐55 years (mean 31.41 ± 10.33). Both methods significantly increased skin hydration and TEWL (P < .001). The capacitance value significantly increased immediately after bathing, and then rapidly decreased within 3 minutes. It returned to baseline by 10 minutes after bathing. There was no statistically significant difference of capacitance between the two methods at any measurement (P > .05). TEWL at every measurement after bathing was significantly increased compared to baseline for both bathing methods (P < .001). The highest TEWL was observed immediately after bathing, but then significantly decreased compared to the previous measurement (P < .001).

Conclusion

Immersion and showering similarly demonstrated significant increase in skin hydration and TEWL. The increment of capacitance after bathing returned to baseline level within 10 minutes.
Crack detection via strain measurements in fatigue testing
Authors: Al‐Karawi Hassan , von Bock und Polach Rüdiger U. Franz , Al‐Emrani Mohammad
Published: March 2021

Fatigue cracks have appeared as a significant issue for joints and connections in existing steel structures in the last decades. Therefore, those are a major inspection and maintenance matter for any steel structure's operator. This emphasises the importance of using a reliable detection method to determine the crack size and assessing the severity of such a crack on the structural integrity of a structure. In this article, the effectiveness of strain measurement in detecting fatigue cracks in transversal non‐load carrying welded attachment subjected to out of plane axial loading is studied. Numerical analysis and experimental investigations allowed to correlate the decrease in strain measured by attached gauges to the crack depth at the weld toe. In addition, different strain evolution patterns were found during fatigue testing, and the fracture surfaces of the specimens were observed to interpret these patterns. Moreover, the crack position with respect to the weld toe surface was predicted via strain measurements.
Conversions in Form Feature Recognition Using Convex Decomposition
Authors: Kim Yong Se , Roe Kenneth D.
Published: March 2021

A convergent convex decomposition method called Alternating Sum of Volumes with Partitioning (ASVP) has been used to recognize volumetric form features intrinsic to the product shape. The recognition process is done by converting the ASVP decomposition into a form feature decomposition by successively applying combination operations on ASVP components. In this paper, we describe a method to generate new combination operations through inductive learning from conversion processes of primal and dual ASVP decompositions when one decomposition produces more desirable form feature information than the other.
Computer Aided Design of Cables for Large Computer Systems: A Case Study in Quick Prototyping
Authors: Korngold Jacob , Gabriele Gary
Published: March 2021

A CAD system for designing cables for large computer systems was developed using a quick prototyping approach. The quick prototyping approach allowed the CAD system developers to quickly converge on software system specifications, system architecture, module designs, and database requirements by enabling the users to test drive many versions of the system, and articulate their needs in a more natural way than reviewing software lifecycle documentation. This development approach relies on a prototyping environment which allows a programmer to quickly design and implement user interface screens with various devices such as buttons, radio dials, scroll bars, text entry fields, pull down menus, and the like, and to logically link them so that various design scenarios can be played out. The idea is to present the look and feel of the proposed CAD tool without implementing any algorithms or databases. Software development using quick prototyping as described in this paper has been an effective means for rapidly converging on an unambiguous design specification for a software tool. Implementation of production ready software is currently underway. The software and database implementation are easier than without the prototype due to the completeness and lack of ambiguity of the specification.
Non-Constant Parameter NC Tool Path Generation on Sculptured Surfaces
Authors: Huang Yunching , Oliver James H.
Published: March 2021

An algorithm for three-axis NC tool path generation on sculptured surfaces is presented. Non-constant parameter tool contact curves are defined on the part by intersecting parallel planes with the part model surface Four essential elements of this algorithm are introduced: initial chordal approximation, true machining error calculation, direct gouge elimination, and non-constant parameter tool pass interval adjustment. A software implementation of this algorithm produces graphical output depicting the tool path superimposed over the part surface, and it outputs cutter location (CL) data for further postprocessing. Several applications examples are presented to demonstrate the capabilities of the algorithm The results of this technique are compared to those generated from a commercially available computer-aided manufacturing program, and indicate that equivalent accuracy is obtained with many fewer CL points.
Development and Application of Graphics Displays for a Mini-Computer Based Vibration Analysis System
Authors: Trevillion Bill
Published: March 2021

Radian Corporation has developed extensive data display capabilities to analyze vibration and acoustic data from structures and rotating equipment. The Machinery Interactive Display and Analysis System (MIDAS) displays data collected through the acquisition functions of MIDAS. The graphics capabilities include displaying spectra in three-dimensional waterfall and in X-Y formats. Both types of plots can relate vibrations to time, equipment speed, or process parameters. Using menu-driven parameter selection, data can be displayed in formats that are the most useful for analysis.

The system runs on a popular mini-computer, and it can be used with a great variety of graphics terminals, workstations, and printer/plotters. The software was designed and written for interactive display and plotting. Automatic plotting of large data files is facilitated by a batch plotting mode. The user can define display formats for the analysis of noise and vibration problems in the electric utility, chemical processing, paper, and automotive industries. This paper describes the history and development of graphics capabilities of the MIDAS system. The system, as illustrated in the examples, has proven efficient and economical for displaying large quantities of data.
Shock Damage to Sensitive Components in an Armored Vehicle
Authors: Gupta Aaron Das , Santiago Joseph M. , Wisniewski Henry L.
Published: March 2021

Light combat vehicles are playing an important support role for both troops and other heavily armored combat vehicles. As such, they have a much greater risk than in previous roles of being subjected to transient loads such as impact and overpressure loads. Propagation of ballistic shock from an impacted region to the critical locations and attachment points for secondary systems can cause damage and misalignment to sensitive equipments contributing to malfunction and reduction of vehicle performance. The Army is actively engaged in a program to assess ballistic shock propagation damage and minimize sensitivity of secondary systems to such damage. The current investigation is devoted to the determination of response at critical locations of the vehicle hull structure of the APC M113 when subjected to a concentrated side-on nonpenetrating impact load.
Nonlinear Dynamic Stability Analysis Using Adaptive Bisection Algorithm in Implicit Integration
Authors: Lee Sang H.
Published: March 2021

There are various categories of dynamic instability. Those are dynamic buckling (or flutter), bifurcation, and dynamic snap-through. Critical conditions for the dynamic buckling are dictated by applied loads, applied momentum or frequency of excitation. This paper presents a few categories of dynamic instability phenomena. Some nonlinear problems shown to exemplify the dynamic instabilities were analyzed using adaptive bisection algorithm in the implicit direct time integration.
Implementation of p and h-p Versions of the Finite Element Method
Authors: Lai Ye-Chen , Liang Timothy C. S. , Jia Zhenxue
Published: March 2021

Based on hierarchic shape functions and an effective convergence procedure, the p-version and h-p adaptive analysis capabilities were incorporated into a finite element software system, called COSMOS/M. The range of the polynomial orders can be varied from 1 to 10 for two dimensional linear elastic analysis. In the h-p adaptive analysis process, a refined mesh are first achieved via adaptive h-refinement. The p-refinement is then added on to the h-version designed mesh by uniformly increasing the degree of the polynomials. Some numerical results computed by COSMOS/M are presented to illustrate the performance of these p and h-p analysis capabilities.
Path Planning for Spatial Robots With Multiple Spherical and Cylindrical Obstacles Inside the Workspace
Authors: Shieh Menq-Dar , Crane Carl , Duffy Joseph
Published: March 2021

Algorithms which can rapidly generate collision free paths for the end effector tip of a spatial 4R manipulator with multiple spherical or cylindrical obstacles inside the workspace have been successfully developed. The algorithms are based on the geometry of the manipulator workspace. The problem of guiding the spatial 4R manipulator while avoiding the obstacles is reduced to that of moving a point and at the same time avoiding rectangles in a Inclination Angle Coordinate System (IACS). The complexity of the path planning is reduced from the 3D case to the 2D case in the IACS, and the speed of generating the collision free paths is improved significantly without losing the characteristics of 3D path planning.

The algorithms have been successfully implemented in a Silicon Graphics 4D-70GT workstation to verify the results. The computation time for generating 10 collision free paths with 7 spherical obstacles or 10 cylindrical obstacles inside the workspace is 1 or 2 seconds. Also, the algorithms, which are designed as interactive programs, are modified to guide a spatial T3586 robot around pipes with circular cross sections.
A Generalized Kinematic for Calculating and Evaluating Surface Geometry of Gears and Cutting Tools
Authors: Grill J. , Hirschmann K. H. , Lechner G.
Published: March 2021

A new method for simulating the cutting and grinding process of gears has been developed. The procedure, implemented on a workstation, allows to describe the most general case of spatial motion based on line coordinates. The meshing of two gears is replaced by the motion of two axodes, rolling and sliding on each other about and along the instantaneous screw axis. A general equation of meshing has been developed, also based on line geometry. Velocity, acceleration and jerk can be determined, which are used for calculating the generated surfaces and their derivatives.
The Calculation of Contact Deformation for Double Circular-Arc Gears
Authors: Tingjian Zhang
Published: March 2021

The Double Circular-arc gear (W-N gear) transmission is well-known as the high contact strength, good wear resisting property and well distributed wears. As developing of its applications in recent years, the contact deformation of W-N gear become more important. In this paper, under basic assumption, the equations for calculating contact deformation of Double Circular-arc gear tooth were derived by using theory of elasticity of general contact problem between arbitrary elastic bodies in three dimensions. The equations were proved by industrial gear applications (one of the example: transmission power N = 3000KW, circumferential speed V = 120 m / s, load fact K = 188 N / cm2, the hardness of tooth surface Hv > 600, surface roughness of tooth Ra < 0.32μm). The relationship between contact deformation of Double Circular-arc gear and helical angle (β), ratio of tooth numbers (u) and central distance (c) was also discussed in this paper. The result of this study provides an inportant reference for tooth stiffness and tooth correction calculation of Double Circular-arc gears.
Reconsideration of the LogiX Gear Using a General Mathematical Model of Composite Gear Profiles
Authors: Tsai Y. C. , Chang H. L.
Published: March 2021

A general mathematical model is derived for describing the conjugate tooth profiles and meshing properties of composite gears. Via a typical gear parameter, the pressure angle, necessary conditions that determine the continuity of composite gears in tooth geometry and meshing properties are introduced. The peculiarity of the presented model is that composite gears can be parametrically characterized by the specific functions in terms of pressure angle. An example is demonstrated that the discontinuity in composite gears will be efficiently and logically solved.

In this paper the LogiX gear, a special composite gear which consists of many segmental “S” curves in gear profiles and possesses zero values of relative curvature and specific sliding at the joints of connected segmental profiles, will be parametrically investigated by this model. The “ideal” LogiX gear profile, theoretically, is constructed by infinite numbers of segmental profiles such that it may have infinite numbers of zero values of relative curvature and specific sliding. However, this “ideal” LogiX gear profile is characterized as a linear parametric profile that is a monotonous curve substantially and no more has infinite numbers of the zero values. Finally, many parametric gears which own power relative curvature and specific sliding than that of the “ideal” LogiX gear profile are presented.
Minimization of Deviations of Gear Real Tooth Surfaces Determined by Coordinate Measurements
Authors: Litvin F. L. , Kuan C. , Wang J.-C. , Handschuh Robert F. , Masseth J. , Maruyama N.
Published: March 2021

The deviations of a gear’s real tooth surface from the theoretical surface are determined by coordinate measurements at the grid of the surface. A method has been developed to transform the deviations from Cartesian coordinates to those along the normal at the measurement locations. Equations are derived that relate the first order deviations with the adjustment to the manufacturing machine-tool settings. The deviations of the entire surface are minimized. The minimization is achieved by application of the least-square method for an overdetermined system of linear equations. The proposed method is illustrated with a numerical example for hypoid gear and pinion.
Dynamic Analysis of Gear Meshing Teeth Using Modified Timoshenko Beam Theory
Authors: Xie M. , Amirouche F. M. L. , Valco M.
Published: March 2021

An explicit dynamical formulation of the gear meshing teeth using modified Timoshenko beam theory is presented in this paper. The acting position direction and magnitude of the external force is assumed time variant. The meshing tooth is modeled as a cantilever beam where the inertia forces due to the large rotation of the tooth base, as well as the external equivalent axial force and moment are all included in the equations of motion. Computer algorithms for gear dynamics based on the theory developed is presented. In the numerical simulations, the involute for the gear tooth profile is considered.
A Study on the Shrinkage Characteristics and Dimensional Accuracy of Cast Gears
Authors: Adjunta Jimmy , Houser Donald
Published: March 2021

This paper is primarily concerned with the evaluation of the dimensional quality of spur gears produced by two casting processes, i. e., the investment casting and v-sand casting processes. The casting patterns used were designed by compensating for process shrinkage, and were manufactured using a flexible CNC gear machining process. A computer program, CASTGR, was written to facilitate the design phase of the patterns. The various gear configurations cast were inspected using an universal coordinate measuring machine. The geometry of the casting and pattern were correlated to verify the contraction characteristics of the gear castings. In an attempt to categorize the precision capabilities of the two casting processes, the spread of the deviations found for tooth thickness measurements and measurements along profiles and leads of the cast gears were examined. The observed effects of other process variables is also included.
BESHOP: A Program Package for Shape Optimization in 2-D Elasticity Problems
Authors: Farshi Behrooz , Moradi Shapour
Published: March 2021

In this paper a package is introduced which handles shape optimization in 2-dimensional elasticity problems where Boundary Element Method is used for the analysis phase affording a large reduction in the problem dimensionality together with a variant of the Method of Center Points for the optimization phase. This optimization method allows a high reduction in the number of constraints considered in each step, as well as low number of cycles, resulting in notable overall efficiency.

Design variables in optimum shape determination consists of basic nodal coordinates for B-spline functions as the means to define smooth boundary curves. Maximum stress and/or displacements at critical boundary points are observed as constraints in each cycle of the procedure.

Three classical case examples are solved successfully, and the results are compared with those of others, illustrating the superior capabilities of the program package.
On Global Feasible Search for Global Design Optimization With Application to Generalized Polynomial Models
Authors: Lo Chihsiung , Papalambros Panos Y.
Published: March 2021

A powerful idea for deterministic global optimization is the use of global feasible search, namely, algorithms that guarantee finding feasible solutions of nonconvex problems or prove that none exists. In this article, a set of conditions for global feasible search algorithms is established. The utility of these conditions is demonstrated on two algorithms that solve special problem classes globally. Also, a new model transformation is shown to convert a generalized polynomial problem into one of the special classes above. A flywheel design example illustrates the approach. A sequel article provides further computational details and design examples.
A Convex Cutting Plane Algorithm for Global Solution of Generalized Polynomial Optimal Design Models
Authors: Lo Chihsiung , Papalambros Panos Y.
Published: March 2021

Global optimization algorithms for generalized polynomial design models using a global feasible search approach was discussed in a previous article. A new convex cutting plane algorithm (CONCUT) based on global feasible search and with improved performance is presented in this sequel article. Computational results of the CONCUT algorithm compared to one using linear cuts (LINCUT) are given for various test problems. Two design examples, a speed reducer and a corrugated bulkhead design, illustrate the application of the algorithms.
Some Further Results for a Reduction Method in Nonhierarchical Optimization-Based Design
Authors: Wu Bi-Chu , Azarm Shapour
Published: March 2021

In a previous article, a new and simple reduction method was presented for optimization-based design of nonhierarchically decomposed engineering systems. As a sequel to that work, in this paper we first examine some significant issues in relation to the reduction method: the optimality conditions when the method is applied, the reason why move limits are not required, and some of the factors that might affect the robustness of the cumulative constraints. For verification and validation, we then present some numerical test results in which the method is applied to twenty-one (21) test problems. Based on the test results reported, some guidelines for applying the method are suggested.
Determination of Significance of Stress Stiffening Effects in Flexible Multibody Dynamic Systems
Authors: Ryu Jeha , Kim Sang Sup , Kim Sung-Soo
Published: March 2021

This paper presents a criterion for determining whether or not a flexible multibody dynamic system reveals stress stiffening effects. In the proposed criterion, the eigenvalue variation that results from adding the modal stress stiffness matrix to the conventional linear modal stiffness matrix is examined numerically before actual dynamic simulation. If the variation is sufficiently large for any flexible body, then stress stiffening effects are said to be significant and must be included in dynamic simulation of flexible multibody systems. Since the criterion uses the most general stress stiffness matrix, which can be represented as a function of applied and constraint reaction loads as well as of a system of 12 inertial loads, this criterion is applicable to any general flexible multibody dynamic systems. Several numerical results are presented to show the effectiveness of the proposed criterion.
A Model for Mechanism Data Storage
Authors: Wang Wan
Published: March 2021

A data model for kinematic structure of mechanisms and its coding principle are proposed, based on the topological graph and contract graph. In the model every basic chain is mapped by a code of 5 decimal digits and a mechanism is mapped by a set of code of basic chains. The model occupies minimal memory, and contains a complete set of useful primary parameters of structure, and significantly reduce computer time for isomorphism identification.
Parametric Surface Intersections for Geometric Modeling
Authors: Chen J.-M. , Wang Yu , Guroz E. L. , Prinz Fritz B.
Published: March 2021

A surface-surface intersection algorithm is an important element in the development of a geometric modeler. This paper presents a new algorithm for calculating the intersection curves of two parametric surfaces. Combining the merits of subdivision and global exploration methods, this algorithm is efficient and robust in dealing with the issues related to small loops and singularities. This algorithm is demonstrated with examples of non-uniform rational B-spline surfaces.
Intersection of Offset Surfaces of Parametric Patches
Authors: Wang Yu
Published: March 2021

In this paper, we present a new method to calculate intersection curve of offset surfaces of two parametric surface patches. This method is based on the concept of normal projection and the intersection problem is formulated with a set of tensorial differential equations. The intersection is represented in the parametric spaces of the base surfaces and no offset surface approximation is needed. Numerical examples are presented for non-uniform rational b-spline (NURBS) surfaces to illustrate the effectiveness and efficiency of the proposed approach.