bluuebunny/crossref_metadata_2025 huggingface dataset:
Circulating sex steroids coregulate adipose tissue immune cell populations in healthy men
Authors: Rubinow Katya B. , Chao Jing H. , Hagman Derek , Kratz Mario , Van Yserloo Brian , Gaikwad Nilesh W. , Amory John K. , Page Stephanie T.
Published: July 2017

Male hypogonadism results in changes in body composition characterized by increases in fat mass. Resident immune cells influence energy metabolism in adipose tissue and could promote increased adiposity through paracrine effects. We hypothesized that manipulation of circulating sex steroid levels in healthy men would alter adipose tissue immune cell populations. Subjects ( n = 44 men, 19–55 yr of age) received 4 wk of treatment with the gonadotropin-releasing hormone receptor antagonist acyline with daily administration of 1) placebo gel, 2) 1.25 g testosterone gel (1.62%), 3) 5 g testosterone gel, or 4) 5 g testosterone gel with an aromatase inhibitor. Subcutaneous adipose tissue biopsies were performed at baseline and end-of-treatment, and adipose tissue immune cells, gene expression, and intra-adipose estrogen levels were quantified. Change in serum total testosterone level correlated inversely with change in the number of CD3+ (β = −0.36, P = 0.04), CD4+ (β = −0.34, P = 0.04), and CD8+ (β = −0.33, P = 0.05) T cells within adipose tissue. Change in serum 17β-estradiol level correlated inversely with change in the number of adipose tissue macrophages (ATMs) (β = −0.34, P = 0.05). A negative association also was found between change in serum testosterone and change in CD11c+ ATMs (β = −0.41, P = 0.01). Overall, sex steroid deprivation was associated with increases in adipose tissue T cells and ATMs. No associations were found between changes in serum sex steroid levels and changes in adipose tissue gene expression. Circulating sex steroid levels may regulate adipose tissue immune cell populations. These exploratory findings highlight a possible novel mechanism that could contribute to increased metabolic risk in hypogonadal men.
Estimation of Antioxidant Levels in Saliva and Serum of Chronic Periodontitis Patients with and without Ischemic Heart Disease
Authors: Punj Anahita , Shenoy Santhosh , Kumari N. Suchetha , Pampani Priyanka
Published: July 2017

Objective. To investigate whether there is a relationship between periodontitis and ischemic heart disease by estimation of total antioxidant status in saliva and serum. Materials and Methods. A total of 80 samples were collected and divided equally into 4 groups of healthy controls, chronic periodontitis patients, ischemic heart disease patients with periodontitis, and ischemic heart disease patients without periodontitis. Saliva and venous blood samples were collected and analyzed for levels of total antioxidant capacity, superoxide dismutase, glutathione peroxidase, and catalase. Results. There were significant (p<0.05) differences in the mean serum levels of total antioxidant capacity (p<0.001), superoxide dismutase (p<0.001), glutathione peroxidase (p<0.006), and catalase (p<0.001) within the 4 groups, whereas the mean salivary levels were significant only for glutathione peroxidase (p=0.001). Both of these serum and salivary antioxidant levels were lower in disease groups of IHD + CP, IHD + H, and CP as compared to healthy controls, with different patterns. Conclusion. Antioxidant capacity is significantly hampered in chronic periodontitis and ischemic heart disease patients with or without periodontitis as compared to healthy controls. The salivary and serum antioxidants may not follow the same increase or decrease as a result of increased oxidant stress due to disease.
Dynamic Shift Coordinated Control Based on Motor Active Speed Synchronization with the New Hybrid System
Authors: Yan Ting , Yang Lin , Yan Bin , Zhou Wei , Chen Liang , Zhou Wei
Published: July 2017

Considering the inherent disadvantages that severely affect driving comfortability during the shift process in HEVs, a dynamic shift coordinated control based on motor active speed synchronization is proposed to improve shift quality by reduction of shift vibration. The whole control scheme is comprised of three phases, preparatory phase, speed regulation phase, and synchronization phase, which are implemented consecutively in order. The key to inhibiting impact and jerk depends on the speed regulation phase, where motor active speed synchronization is utilized to reach the minimum speed difference between the two ends of synchronizer. A new hybrid system with superior performances is applied to present the validity of the adopted control algorithm during upshift or downshift, which can represent planetary gear system and conventional AMT shift procedure, respectively. Bench test, simulation, and road test results show that, compared with other methods, the proposed dynamic coordinated control can achieve shifting control in real time to effectively improve gear-shift comfort and shorten power interruption transients, with robustness in both conventional AMT and planetary gear train.
Genetic Variants in SNCA and the Risk of Sporadic Parkinson’s Disease and Clinical Outcomes: A Review
Authors: Campêlo Clarissa Loureiro das Chagas , Silva Regina Helena
Published: July 2017

There is increasing evidence of the contribution of genetic susceptibility to the etiology of Parkinson’s disease (PD). Genetic variations in the SNCA gene are well established by linkage and genome-wide association studies. Positive associations of single nucleotide polymorphisms (SNPs) in SNCA and increased risk for PD were found. However, the role of SNCA variants in individual traits or phenotypes of PD is unknown. Here, we reviewed the current literature and identified 57 studies, performed in fourteen different countries, that investigated SNCA variants and susceptibility to PD. We discussed the findings based on environmental factors, history of PD, clinical outcomes, and ethnicity. In conclusion, SNPs within the SNCA gene can modify the susceptibility to PD, leading to increased or decreased risk. The risk associations of some SNPs varied among samples. Of notice, no studies in South American or African populations were found. There is little information about the effects of these variants on particular clinical aspects of PD, such as motor and nonmotor symptoms. Similarly, evidence of possible interactions between SNCA SNPs and environmental factors or disease progression is scarce. There is a need to expand the clinical applicability of these data as well as to investigate the role of SNCA SNPs in populations with different ethnic backgrounds.
Combustion and Mechanical Properties of Polymer-Modified Cement Mortar at High Temperature
Authors: Kim Hyung-Jun , Park Won-Jun
Published: July 2017

Although polymer-modified cement mortar (PCM) has been extensively used as finishing and repairing material, it is necessary to understand its combustion properties and mechanical properties at high temperature. This study evaluated the combustion characteristics with varying experimental parameters such as polymer type, unit polymer content, polymer-cement ratio, and thickness of the specimen. This study also evaluated the compressive strength and elastic modulus of PCMs with focus on the effects of the type of polymer, unit polymer content, and polymer-cement ratio. As a result, the incombustibility of the PCM was in the following order: SBR < VVA < EVA. After heating end, the mass loss rate of the PCM was less than 30%, regardless of the polymer type, unit polymer content, and W/C. In heat release rate test, the higher the unit polymer content, the greater the total heat release, regardless of the difference in W/C. The PAE series showed excellent fire resistance in the temperature range of 200~400°C. PCMs with a unit polymer content of 5%, modified with EVA and PAE, showed outstanding compressive strength at 200~400°C. At elevated temperature, the modulus of elasticity of PCM declined with an increase in the unit polymer content, regardless of the polymer type.
Review of Organism Density and Bacteriologic Conversion of Sputum among Tuberculosis Patients
Authors: Osei Francis Adjei , Enimil Anthony , Ansong Daniel , Laryea Dennis Odai , Mensah Nicholas Karikari , Amuzu Evans Xorse , Agyemang Ebenezer Opambour , Sarpong Phans Oduro , Nyanor Isaac , Dekugmen Yar Denis
Published: July 2017

Objective. This study sought to describe the trend of sputum organism density and the rate of bacteriological conversion among smear positive TB patients assessing care at the Komfo Anokye Teaching Hospital (KATH), Kumasi, Ghana. Methods. We conducted a retrospective patient folder review from January 2013 to March 2016 at the KATH, a tertiary hospital in Ghana. The data was entered into Microsoft Access database and exported into STATA for analysis. We applied basic descriptive statistics to study variables. Sputum conversion rate (SCR) was estimated using the number of negative tests recorded over a period (numerator) and the number of patients reported in the same period (denominator) and expressed as a percentage. Results. A total of 278 patient records with sputum smear positive at onset were studied. Before treatment sputum density detected in smear microscopy was as follows: 1 acid-fast bacillus (+) (n=114), scanty (n=19), ++ (n=67), and +++ (n=78). We recorded sputum conversion rate of 80.90%, 94.56%, and 98.31% in the intensive, continuation, and completion phases, respectively. Conclusion. This study has shown an increasing trend in sputum conversion of smear positive pulmonary tuberculosis and an increasing trend in loss to follow-ups among tuberculosis patients on treatment.
Game Approach for H∞ Robust Control Strategy to Follow the Production in the Singularly Perturbed Bilinear Dynamic Input‐Output Systems
Authors: Bin Ning , Zhang Chengke , Zhu Huainian , Liu Qiyou
Published: July 2017

For simulating and analyzing the input and output problem of national economy more accurately, this paper considers the fast and slow production processes during the course of social production development, takes stochastic economic risks into consideration, and constructs a H∞ robust control model to follow the production in the singularly perturbed dynamic input‐output systems. Further introducing ideas of noncooperative differential game theory, the H∞ robust control model is transformed into a saddle‐point equilibrium game model, and a new method for solving dynamic input‐output problem by using saddle‐point equilibrium strategies is obtained. A numerical result is presented in the end to illustrate the effectiveness of the method.
Routine Cysticotomy and Flushing of the Cystic Duct in Patients with Low Risk of Common Duct Stones: Can It Be Beneficial?
Authors: Leon Piera , Giudici Fabiola , Sciuto Antonio , Corcione Francesco
Published: July 2017

Background. Gallstone disease affects 15–20% of the general population and up to 20% of these patients present common bile duct stones. Aim. This observational study reports our experience on routine cysticotomy and flushing of the cystic duct in patients with low risk of common duct stones. Materials and Methods. We analyzed 731 patients who underwent laparoscopic cholecystectomy between September 2013 and September 2015. Results. Patients were preoperatively stratified on the clinical risk; those presenting with low preoperative risk of common bile duct stones were referred to undergo laparoscopic cholecystectomy and routine cysticotomy with bile duct flushing. Patients presenting thick bile sludge, solid debrides, and/or increased tension of bile outflow underwent unplanned cholangiography. No intraoperative complications or conversion to open technique occurred. Average follow-up time was 22,8 months (range 12 to 37). Rate of retained ductal stones accounted for 0,3%. Conclusions. Routine cysticotomy and bile flushing in our experience is a valid, simple, and not time consuming manoeuvre that can help decompressing and flushing CBD. Moreover, it is a valid tool for extending selective IOC approach in a focused manner. Further evaluations have to be conducted to evaluate risks and effectiveness of this manoeuvre.
Perinatal Outcomes of Non-Primary Maternal Cytomegalovirus Infection: A 15-Year Experience
Authors: Simonazzi Giuliana , Curti Alessandra , Cervi Francesca , Gabrielli Liliana , Contoli Margherita , Capretti Maria Grazia , Rizzo Nicola , Guerra Brunella , Farina Antonio , Lazzarotto Tiziana
Published: July 2017

Objective: To evaluate perinatal outcomes in case of non-primary maternal cytomegalovirus (CMV) infection. Methods: We performed a retrospective cohort study of pregnant women with active CMV infection referred to our unit over a 15-year period (January 2000 to December 2014). Non-primary infection was diagnosed on the basis of the results of confirmatory serological and virological tests (avidity test, immunoblotting, real-time PCR-DNA). The vertical transmission rate and the percentage of symptomatic congenital infection were determined in this group of patients. Results: A total of 205 pregnant women were enrolled. Congenital infection occurred in 7 (3.4%) fetuses/neonates. Symptomatic disease was present at birth in 3 of the 7 congenitally infected neonates (1.5%). Two out of 3 symptomatic newborns presented a pathologic second-trimester ultrasound scan. Conclusion: Maternal immunity offers substantial protection against intrauterine transmission of CMV infection, but not against disease once the fetus is infected.
Fatal Gastrointestinal Hemorrhage in a Patient with Brunner’s Gland Hyperplasia
Authors: Meltser Edward , Federici Matthew , Cooper II Robert , Capanescu Cristina , Behling Kathryn C.
Published: July 2017

Brunner’s gland hyperplasia is a rare cause of duodenal mass and gastrointestinal hemorrhage. Imaging and esophagoduodenoscopic evaluation of this condition are frequently consistent with a duodenal malignancy often resulting in surgical resection. However, the malignant potential of these lesions is still unknown, and most are benign. We report the case of a 74-year-old man who presented with fatal gastrointestinal bleeding and esophagoduodenoscopy findings consistent with a duodenal mass and mucosal ulceration. At autopsy, histologic examination of the mass revealed Brunner’s gland hyperplasia with associated ulcer formation. In this report, we review the findings associated with this case as well the literature regarding presentation, clinical associations, and treatment of Brunner’s gland hyperplasia.
A Case of Recurrent Breast Cancer Identified by Pulmonary Tumor Thrombotic Microangiopathy
Authors: Abe Tomomi , Fukada Ippei , Shiga Taro , Morizono Hidetomo , Ikebata Koichi  , Shibayama Tomoko  , Kobayashi Kokoro  , Iwase Takuji  , Ohno Shinji , Ito Yoshinori
Published: July 2017

Pulmonary tumor thrombotic microangiopathy (PTTM) is a rare, cancer-related, pulmonary complication that causes hypoxia and pulmonary hypertension. We report on a 42-year-old woman who was diagnosed with recurrent breast cancer that was detected due to the presence of PTTM. Eleven months after surgery for heterochronous bilateral cancer of the left breast, she developed progressive dyspnea but computerized tomography showed no pulmonary thromboembolism, and a transthoracic echocardiography revealed mild pulmonary hypertension. She was diagnosed with PTTM by cytology from pulmonary artery catheterization and perfusion lung scintigraphy. Also, the patients complained of back pain after admission, bone scintigraphy showed multiple bone metastases. Despite the early diagnosis of PTTM, her platelet count decreased, her performance status rapidly deteriorated, and her dyspnea worsened. Thus, we could not treat her with chemotherapy. She died due to respiratory failure 19 days after admission. To the best of our knowledge, this is the first report of recurrent breast cancer identified by the manifestation of PTTM. Although PTTM is a rare phenomenon, it should be considered in the differential diagnosis of acute dyspnea or pulmonary hypertension in patients with breast cancer. Furthermore, upon diagnosis, the patient should be referred to a cardiologist as soon as possible.
Cystoid Macular Edema during Treatment with Paclitaxel and Bevacizumab in a Patient with Metastatic Breast Cancer: A Case Report and Literature Review
Authors: Yokoe Takamichi , Fukada Ippei , Kobayashi Kokoro , Shibayama Tomoko , Miyagi Yumi , Yoshida Atsushi , Iwase Takuji , Ohno Shinji , Ito Yoshinori
Published: July 2017

We present a case of a metastatic breast cancer patient with cystoid macular edema (CME) occurring during treatment with paclitaxel and bevacizumab. She had a history of neoadjuvant chemotherapy and partial mastectomy plus axillary lymph node dissection for stage IIB left-breast cancer. Twenty-four months later, she was diagnosed with multiple bone metastases and underwent chemotherapy with paclitaxel and bevacizumab. Thirty-three months after the initiation of the chemotherapy, she noticed bilateral blurred vision. The retinal thickening with macular edema was observed by optical coherence tomography, resulting in a diagnosis of CME. With cessation of paclitaxel and administrating ocular instillation of a nonsteroidal anti-inflammatory drug, her macular edema gradually reduced and disappeared in a month. While CME caused by chemotherapy is very rare, taxane may cause ocular adverse events such as CME. It is important to urge patients to consult an ophthalmologist promptly when they have visual complaints during taxane chemotherapy.
Myocardial Upregulation of Cathepsin D by Ischemic Heart Disease Promotes Autophagic Flux and Protects Against Cardiac Remodeling and Heart Failure
Authors: Wu Penglong , Yuan Xun , Li Faqian , Zhang Jianhua , Zhu Wei , Wei Meng , Li Jingbo , Wang Xuejun
Published: July 2017

Background

Lysosomal dysfunction is implicated in human heart failure for which ischemic heart disease is the leading cause. Altered myocardial expression of CTSD (cathepsin D), a major lysosomal protease, was observed in human heart failure, but its pathophysiological significance has not been determined.

Methods and Results

Western blot analyses revealed an increase in the precursor but not the mature form of CTSD in myocardial samples from explanted human failing hearts with ischemic heart disease, which is recapitulated in chronic myocardial infarction produced via coronary artery ligation in
Ctsd
+/+
but not
Ctsd

+/−

mice. Mice deficient of
Ctsd
displayed impaired myocardial autophagosome removal, reduced autophagic flux, and restrictive cardiomyopathy. After induction of myocardial infarction, weekly serial echocardiography detected earlier occurrence of left ventricle chamber dilatation, greater decreases in ejection fraction and fractional shortening, and lesser wall thickening throughout the first 4 weeks; pressure–volume relationship analyses at 4 weeks revealed greater decreases in systolic and diastolic functions, stroke work, stroke volume, and cardiac output; greater increases in the ventricular weight to body weight and the lung weight to body weight ratios and larger scar size were also detected in
Ctsd

+/−

mice compared with
Ctsd

+/+

mice. Significant increases of myocardial autophagic flux detected at 1 and 4 weeks after induction of myocardial infarction in the
Ctsd

+/+

mice were diminished in the
Ctsd

+/−

mice.

Conclusions

Myocardial CTSD upregulation induced by myocardial infarction protects against cardiac remodeling and malfunction, which is at least in part through promoting myocardial autophagic flux.
Histopathological indices of WSSV infection in target tissues and their correlation with hindgut infections in Penaeus vannamei (Decapoda, Dendrobranchiata)
Authors: Kakoolaki S. , Afsharnasab M.
Published: July 2017

The White Spot Syndrome Virus has already posed a serious threat to industrial shrimp culture for many years. We studied this disease in Penaeus vannamei. A total of 100 specimens was used to evaluate tissue tropism for WSSV. In case of infectious correlations among the tissues, Kendall’s tau-b test showed that there were significant differences () among the target tissues. The rates of frequency for infected target tissues, which should be calculated between 0 and 1, were 0.71, 0.58, 0.61 and 0.12, respectively, for haemolymph, hindgut epithelial cells, cephalothoracic epidermis, and interstitial tissue of the hepatopancreas. Results indicated that 88% of the gills, 98% of the muscles, 97% of haematopoietic nodules and 97% of the hearts were not severely infected, but these rather showed relatively mild infections. It can be suggested that epithelial cells of the gills prevent replication of the virus in the early stage of WSSV infection, whereas meanwhile epithelial cells of the cephalothorax and those of the hindgut, in contrast, boost the replication of WSSV. Additionally, morphological haemocytic evaluation can be applied as an appropriate infectious indicator in the early stage of WSSV disease in farmed P. vannamei.
Streptocephalus sangoensis n. sp. (Anostraca, Streptocephalidae), a new large branchiopod species for southern Africa
Authors: Nhiwatiwa Tamuka , Dalu Tatenda , Brendonck Luc
Published: July 2017

Recent collections from the south-eastern Lowveld of Zimbabwe yielded an undescribed species of the freshwater branchiopod genus Streptocephalus. The species was formerly published as Streptocephalus cf. bidentatus by Brendonck & Riddoch (1997), indicating that more research was needed to prove its valid species status, distinct from S. bidentatus sensu stricto. The new species can be distinguished from S. bidentatus sensu stricto, mainly by its cercopods. The cercopods of S. bidentatus sensu stricto have spines in the distal third region of the furcal rami, while those of S. sangoensis n. sp. are setiferous up to the tips. All other morphological features are the same. The occurrence of the two species in syntopy further validates that they are different species. As with S. bidentatus sensu stricto, the new species S. sangoensis n. sp. was collected from ephemeral habitats. This region is a hotspot of large branchiopod diversity with a total of 16 known species occurring there.
Umbrella Clauses and Widely-Formulated Arbitration Clauses: Discerning the Limits of icsid Jurisdiction
Authors: Footer Mary E.
Published: July 2017

This article examines the scope and the limits of icsid arbitration involving umbrella or “observance of undertakings” clauses and widely-formulated arbitration clauses, both of which may provide investors with broad recourse to dispute settlement for disputes related to investment, as defined in the applicable bilateral investment treaty (bit). It does so by analysing the origins and rationale behind both clauses as well as how they operate in principle and in practice. It appears there is no jurisprudence constante concerning the application of either clause. However, a clearer picture is emerging in icsid jurisprudence of an effective, occasionally prospective, application of the umbrella clause and some limited deference to widely-formulated arbitration clauses. It is balanced by other icsid arbitral decisions that seek to limit the scope and application of the umbrella clause on a variety of grounds.
Adenia angulosa (Passifloraceae), a new species from coastal forests of Kenya and Tanzania
Authors: NGUMBAU VERONICAH MUTELE , NYANGE MWADIME , DAI CAN , ZHONG ZHI-XIANG , WEI NENG , MALOMBE ITAMBO , HU GUANG-WAN , WANG QING-FENG
Published: July 2017

Adenia angulosa, a new species of Passifloraceae from coastal forests of Kenya and Tanzania is described and illustrated with photographs. It is most similar to A. gummifera, but differs by its angled older stem, leaf shape, fewer flowers per inflorescence, connation of filaments, shape of ovary and fruit, as well as size and shape of seed.
Achene Micromorphology of the Genus Cyanus Mill. (Compositae) in Turkey and its Taxonomic Importance
Authors: ŞİRİN EMRAH , ERTUĞRUL KUDDİSİ , UYSAL TUNA
Published: July 2017

Micro- and macromorphological achene features of 20 knapweeds taxa from Turkey were searched using light and scanning electron microscopy. The achene surface was examined in detail for each taxon and a dendogram was established by numerical analyses derived from the observed micromorphological features. Cyanus pinardii was distinguished by epappose while Cyanus depressus was distinguished by longer pappus than achene. The results indicated that the examined taxa had very high variations in their achene surface. According to the results, pericarp texture and color, hilum position and pappus hairs could be used for taxonomical diagnosis of the Cyanus taxa. The hairiness of the surface and elaiosome in the basal of pericarp were characteristic in all Cyanus taxa.
Niphargus diadematus sp. n. (Crustacea, Amphipoda, Niphargidae), an inhabitant of a shallow subterranean habitat in South Moravia (Czech Republic)
Authors: HUDEC IGOR , FIŠER CENE , DOLANSKÝ JAN
Published: July 2017

We present a subterranean amphipod from genus Niphargus collected in soil traps. Traps were set for sampling soil spiders in the inundation of the Včelínek Brook, Dyje River watershed, Czech Republic. Most likely, the species lives in a shallow subterranean habitat and has likely got entrapped into soil traps at elevated level of groundwater during two floods. In total 189 specimens were collected. The collected amphipods are small, slender and resemble species that were broadly classified to N. aquilex aggregate. Although damaged DNA does not allow more inclusive taxonomic and phylogenetic examination of the species, a comprehensive revision of 19 morphological diagnostic traits for 64 species from the aggregate indicates that these specimens should be treated as a new species, named Niphargus diadematus sp. n.
Notes on the Agrotis colossa Boursin problem, with the description of new Agrotis species from China (Lepidoptera, Noctuidae)
Authors: GYULAI PETER , SALDAITIS AIDAS , TRUUVERK ANDRO
Published: July 2017

The description of Agrotis colossa as sp. n. became necessary, since the original description has never been published and the manuscript was not found in the Boursin heritage. The original name and designation was accepted, however, the type material (holotype male and single allotype female) was completed with a series of males and females from the recent expeditions. The description of Agrotis rachingeri sp. n. is also given and the DNA results in case of both species. New taxa are illustrated with imagines in colour and male and female genitalia.
The Effect of Neighborhood Poverty on Math Achievement: Evidence From a Value-Added Design
Authors: Pearman Francis A.
Published: July 2017

Two trends play an increasing role in shaping the long-term prospects of children across the United States: a growing STEM (science, technology, engineering, and mathematics)-based economy and rising income segregation. Together, they suggest that the future well-being of U.S. children may be based increasingly on the contemporary interplay of mathematical learning and neighborhood environments. Drawing on data from the Panel Study of Income Dynamics and a value-added design, this article provides a rigorous test of the hypothesis that exposure to high-poverty neighborhoods exerts a depressive effect on children’s mathematics achievement growth beyond that associated with individual-, family-, and school-level characteristics. Results indicate that exposure to higher-poverty neighborhoods reduces children’s mathematical growth, a treatment effect roughly equivalent to missing three quarters of a year of schooling over the 5-year treatment period. A formal sensitivity analysis suggests that these effects are remarkably robust to unobserved residual confounding.
On the Conditions of Fragility: Homeless Education Policy, Accountability, and Researcher Reflections
Authors: Aviles Ann M.
Published: July 2017

This article highlights McKinney-Vento awareness and implementation as experienced and understood by unaccompanied youth facing housing instability and the adults charged with its implementation in schools. A qualitative inquiry was used to capture the perspectives of youth experiencing housing instability as they navigated a large urban school district in the Midwest. Research observations and the perspectives of six unaccompanied unstably housed youth attending two high schools in Chicago and the adults charged with providing educational services are presented here. The theme of Policy Awareness and Accountability emerged from the school observations and narratives of the youth and adult experiences. Participant experiences and insight indicate the need to increase school/community awareness and accountability of McKinney-Vento. Last, the author provides reflections on the complexities and fragility of navigating the research process.
A Comparison of Short Forms of the Intelligence Scale for Children - Revised in the Screening of Gifted Referrals
Authors: Killan Janice B. , Hughes Larry C.
Published: July 2017

A total of 142 full scale individual intelligence tests were rescored to compare the V and BD dyad of the WISC-R with the full scale WISC-R and the limen method of scoring of the S-B with the full scale S-B. Tests had been administered to students who had been referred for possible inclusion in a gifted program. The correlation of the limen short form and the full scale S-B was. 78 while the V and BD dyad and full scale WISC-R correlation was .92. Results suggest that the V and BD dyad of the WISC-R may be a useful screening device for superior students.
Freeing Women's Creative Potential
Authors: Morse Jean Alston
Published: July 2017

The Bruch-Morse model of personality characteristics associated with creative productivity in women has potential for use as a diagnostic-prescriptive tool. Some experiences have been suggested for women who wish to move away from dependence or counterdependence toward more productive areas of the model. While the emphasis in this paper has been upon self-assessment in women, some implications may be drawn for the provision of similar, educationally-related experiences for younger girls as well.
Creative Thinking in Gifted Elementary School Children
Authors: Houtz John C. , Rosenfield Sylvia , Tetenbaum Toby J.
Published: July 2017

A varietyof creatine thinking and problem solving tasks were administered to 233 intellectually gifted second through sixth graders at a special school for the gifted in New York City. The tasks were selected to represent conceptual stages of a total creative problem sloving model Intelligence. achievement, and personality data were also gathered. Findings indicated interesting patterns of growth in creative problem .solving abilities. On the creative thinking tasks a plateau in performance appeared from the fourth grade on, but on the problem solning tasks, growth continued through the sixth grade. Individual variation within the sets of creative thinking and prohlem solving tasks was great, suggesting the need for creativity and problem solving skills training for the gifted.
Hemispheric Lateralization, Cerebral Dominance, Conjugate Saccadic Behavior and Their Use in Identifying the Creatively Gifted
Authors: Rekdal C.K.
Published: July 2017

In an effort to establish new means of locating the gifted creative productive thinker, an investigation of current brain research in the areas of hemispheric lateralization, cerebral dominance and conjugate saccadic behavior is analyzed. Although some promise of its possible use in future research dealing with this particular group of gifted population exists, innumerable questions have also been raised.
Microcellular PVC Foam for Thin Wall Profile
Authors: Vanvuchelen Jan , Perugini Carlo , Deweerdt Marc , Chen Lee , Burnham Ted
Published: July 2017

Loss of toughness is a major obstacle for applications of foamed rigid PVC, especially for thin products. With cell sizes below 100 μ, microcellular PVC foams provide much higher toughness while creating new products with thinner walls than those possible with conventional PVC foams. In this original work, a thin-wall microcellular foam PVC product was obtained by the application of the MuCell® process on a commercial scale extrusion line [1]. The process consists of the injection of supercritical fluids as blowing agents into the extruder. The screw and die were modified to achieve single-phase solution and cell nucleation. Foamed thin wall profiles with a thickness of about 0.45 mm were made with a density reduction of up to 30%. The cell size obtained is typically much smaller than 100 μ with little interconnectivity. The profile showed excellent toughness, with a tensile elongation typically higher than 60%, and smooth surfaces.
Optimization of Formulations Based on HFC-365mfc and Blends Thereof
Authors: Dournel Pierre , Zipfel Lothar , BarthéLemy Pierre
Published: July 2017

As already mentioned in our last SPI publications, HFC-365mfc has to be considered as a key building block for a new generation of blowing agents. Interesting blends have been identified in order to answer the demand of the various segments of the rigid foam market. New PU formulations based on HFC-365mfc and blends have now been developed for the laboratory scale.

Whilst the use of HCFC-141b was found to be easy thanks to its good solubility characteristics in standard polyols, the use of HFCs, notably HFC-365mfc is more difficult. Indeed, because of their low polarity, the solubility of HFCs in most standard polyols is limited. This is advantageous for dimensional stability but means that the systems that are being used now will need to be adapted in order to obtain a homogeneous polyol blend.

In this paper, we report on ways to increase the compatibility of HFC-365mfc and blends thereof with polyol systems. The evaluation of foams obtained from these new systems has also been performed in order to allow the selection of the most appropriate combination for a given application.

Foaming trials using the non flammable blend HFC-365mfc/HFC-134a will be presented, especially for spray foam, and one trial using the azeotrope HFC-365mfc/n-pentane for PIR laminates. The main properties being reported are notably the resulting pressure above system premixes, the dimensional stability and the foam thermal conductivity.

SOLVAY have taken the decision to start a pilot plant for HFC-365 mfc in September 1999, and commercial production is planned to come on stream in the year 2002.
Predicting the Performance of Chemical Blowing Agents Using Thermal Analysis Techniques
Authors: Dixon D. , Martin P. J. , Harkin-Jones E.
Published: July 2017

This paper demonstrates how the cell morphology of extruded expanded poly-propylene (EPP) may be related to the thermal decomposition behavior of chemical blowing agents (CBAs) used in their production. The thermal analysis techniques used in this study were differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Tests were completed on six of the CBAs now available for use with PP. It was found that agents with a higher decomposition temperature and rate of gas evolution generally produced foam samples with a smaller cell size and higher cell density. This information will be beneficial to producers and users of CBAs.
Mechanical Behavior of Hybrid Composite Phenolic Foam
Authors: Desai Amit , Auad Maria L. , Hongbin Shen  , Nutt Steven R.
Published: July 2017

Hybrid composite phenolic foams are reinforced with chopped glass and aramid fibers in varied proportions. The mechanical properties are measured and compared with those of foams reinforced with only aramid and glass fibers. The compression and shear properties of the hybrid reinforced foams are also compared with those of commercial polyurethane foams. The reinforced hybrid phenolic foams exhibit greater resistance to cracking and are significantly stiffer and stronger than foams with only glass and Nomex® fibers. In general, the mechanical properties of reinforced hybrid phenolic foams are comparable to that of commercial polyurethane foam of equivalent density. The experimentally observed compressive properties (compression modulus) of reinforced phenolic foam with different fiber loading have been compared with existing theories of reinforcement. Composite models such as parallel, series, Halpin—Tsai, and the Hirsch model have been evaluated to fit the experimental data. The findings presented here, coupled with earlier results, demonstrate the potential use of hybrid composite foams as a low-cost engineering material that is tough, strong, and fire retardant.
Cyclopentane-Blown Rigid Foams for Refrigerators
Authors: Volkert O.
Published: July 2017

Following an intermediate period using HCFCs (R-22, R-142b or R-141b), the next generation for replacing CFCs in appliance-applications is believed to be fluorinated compounds. However, per fluorinated substances have the problem of their high GWPs. Partly fluorinated, liquid compounds (e.g., R-356) are ex-pensive, and their toxicity is not yet completely understood. Partly fluorinated gaseous products (R-134a, R-227) have rather high thermal conductivities.

For these reasons, there is a tendency-at least in Europe-to go straight to an optimum solution and use blowing agents free of halogens.

Extensive studies have shown that hydrocarbons are most suitable, because they have the lowest solubility in the PUR-matrix. As a consequence, they have the best blowing efficiency and the minimum loss of mechanical properties in the foam.

It was found that cycloalkanes have a surprisingly low thermal conductivity compared to normal hydrocarbons and-because of its appropriate boiling point-cyclopentane was chosen as the best candidate.

Optimized formulations yield foams with k-factors similar to the present R-11 system.

The diffusion of cyclopentane through the PUR-matrix was found to be as slow as with R-11.

The disadvantage of cyclopentane is its flammability. However, this problem can be solved.
Potential Improvement of N-Pentane-Based Foam Insulation
Authors: Fan Youchen , Kokko Erkki
Published: July 2017

Ageing of rigid closed-cell cellular plastic is the key problem to be solved in developing new foamed insulation. Diffusion-tight facing is one of the strategies to slow down the ageing process. As an example, n-pentane-based foam insulation was selected to evaluate the possible improvement in thermal performance by using this strategy. It has been found that the average thermal conductivity increase after 10 years is only about 1 mW/m.K for a foam with perfect facing on upper and lower surfaces, whereas the corresponding value is about 4.5 mW/m.K for a commercially available foam with so called "diffusion tight" facing. Thus, further development in foam facing is recommended.
Key Aspects of Novel Catalyst Systems in all-Water Blown Integral Skin Foams-Related Catalytic Activities in the Isocyanate Reaction
Authors: Okuzono S. , Kisaka H. , Tamano Y. , Lowe D. W.
Published: July 2017

This paper will focus on the generalization of catalytic activities of a variety of typical amine and tin catalysts in the isocyanate reaction of gelation, blowing and crosslinking Secondly the relationship between catalytic activities and foaming behavior, as well as foam properties, will be discussed from the stand-point of developing novel catalyst systems for all-water blown integral skin foams (ISF).

Catalysts play an important role in the control and balance between the gelation and blowing reactions. Especially in ISF systems, this control becomes increasingly important for the improvement of surface skin formation in all-water blown systems, which are now required for eliminating CFC. That is to say, skin formation and cure become inferior when using water as a blowing agent, primarily because the role of CFC is to aid in skin formation. Moreover, other than the two primary reactions, it will be considered that the catalytic activity of the crosslinking reactions such as allophanate, biuret and isocyanurate formation will have some effect on foaming behavior as well as foam properties. Therefore, it will be important to know the crosslinking activities for the design of novel catalyst systems.

Concerning the catalytic activities for the primary gelation and blowing reactions, many reports have been presented in the past where the relationships between catalytic activities and foaming behaviors, as well as foam properties, have been reported. On the other hand, several reports have been recently presented on the crosslinking activities, based on the method using HPLC analysis techniques in a model reaction. Few reports, however, describe the reaction kinetic analysis of the catalytic crosslinking activities and the systematic examination of its relation to foaming behavior and foam properties.

In this paper, the catalytic activity of a variety of typical amine and tin catalysts will be generalized with a review on gelation and blowing activities and a reaction kinetic analysis of the crosslinking activities using HPLC analysis in a model reaction.

In addition, the relationship between these catalytic activities and foaming behaviors, as well as foam properties, will be discussed in an all-water blown ISF system. As to the foaming reaction, the relationship between viscosity rise profiles, which may have a large relation to cure, will also be discussed. Concerning foam properties, the relation to cure and skin formation will be discussed. As a result, it will be shown that strong gelling catalysts with high crosslinking activities provide improvement in skin formation. This report will intro-duce novel catalyst systems in all-water blown ISF systems by suggesting the effectiveness of catalytic activities in the selection of a suitable catalyst system.
Evaluation of HFC 245ca and HFC 236ea as Foam Blowing Agents
Authors: Sharpe J. , MacArthur D. , Liu M. , Kollie T. , Graves R. , Hendriks R.
Published: July 2017

Hydrochlorofluorocarbons (HCFCs) have been widely adopted as an interim blowing agent in urethane insulations. Due to their scheduled phase-out, research efforts are being devoted to the identification and development of alternatives with zero ozone depletion potential. Physical blowing agents identified have included hydrocarbons, fluorocarbons, hydrofluoroethers, and more predominantly, hydrofluorocarbons (HFCs). The majority of the HFC evaluations have focused on the more readily available, low boiling candidates such as HFC 134a. Higher boiling HFC candidates that could be handled at ambient conditions and use current processing equipment would be more desirable.

This paper will describe results from a research program of two such candidate HFCs performed as a cooperative effort between the Environmental Protection Agency, Oak Ridge National Laboratory and Martin Marietta Manned Space Systems. The purpose of this effort was to perform a limited evaluation of the developmental HFCs 245ca and 236ea as blowing agents in urethane based insulations. These two materials were selected from screening tests of 37 C2, C3 and C4 isomers based on physical properties, atmospheric lifetime, flammability, estimated toxicity, difficulty of synthesis, suitability for dual use as a refrigerant and other factors. Solubility of the two materials in typical foam components was tested, pour foaming trials were performed and preliminary data were gathered regarding foam insulation performance.
HFC-356, a Zero ODP Blowing Agent Candidate for North American Appliance Foam Formulations
Authors: Ball E. E. , Lamberts W. M.
Published: July 2017

The household refrigeration industry in the U.S. is being challenged on two issues. These issues are depletion of the ozone layer by CFCs and federally mandated energy consumption standards for the products sold in the U.S. The global issue of ozone depletion affects all domestic appliance producers in North America. The energy consumption issue, however, only affects those producers who desire to sell their products in the U.S.

In addressing the ozone depletion issue, the North American manufacturers of household refrigerators and freezers have accepted HCFCs as the most promising available blowing agent substitutes for CFCs in their polyurethane foam insulations. Over the past few years a great deal of effort has gone into the development of polyurethane foam insulations blown with HCFCs which have the properties required by the North American household refrigeration industry. Between now and 1995 we expect a conversion of the industry from CFC to HCFC blown polyurethane foam insulations.

HCFCs, however, are only transition materials. Since their ozone depletion potentials are not zero, they too are scheduled for production caps and phaseout under the provisions of the amendments to the Montreal Protocol. Thus, it is necessary to begin the development now on the next generation of North American appliance foam formulations which do not use ozone depleting substances as blowing agents.

Our previous work has shown the ability to develop appliance foams blown with HFC-356 which satisfactorily meet the technical requirements of the European appliance industry in many important areas. The design and construction differences between European and North American refrigerated appliances, however, does not allow direct translation of appliance foam technology. The foam flowability, k-factor, density and demold requirements are not the same. Consequently, our development effort has now expanded to address the needs of the North American domestic appliance producer. Results of work done with HFC-356-based foam systems engineered for the North American appliance insulation market are presented with comparisons to known CFC and HCFC blown appliance foams.
Low Permeability Polyols for Rigid Foam Applications
Authors: Moore D. R. , Kaplan W. A. , Tabor R. L.
Published: July 2017

The decreased emphasis on the use of CFC blowing agents for rigid foam has placed a greater demand on the performance of the polymer in the foam. One area where higher performance is needed is in permeability. In order for non-CFC foam to retain its insulation performance the permeation of low k-factor blowing agent out of the foam and the permeation of high k-factor air into the foam must be minimized.

This paper will present data on several new types of polyols which have been designed specifically to give lower permeability than conventional rigid foam polyols. Data on the permeability of both air and carbon dioxide for these polyols was developed on both compression molded thermoset polymer films and foam samples. These polyols gave significant improvement in both carbondioxide retention and air exclusion which lead to improved k-factor aging in the foam samples.
New Polyurethane Energy Management Foams for Improved Auto Interior Safety
Authors: Naik B. G.
Published: July 2017

New and upcoming federal standards for occupant safety in automobiles and trucks have increased the need for impact energy management in automotive interiors. The National Highway Traffic Safety Administration (NHTSA) regulations continue to promote improvements in the areas of head, knee, and side impact.

Materials being used or considered for managing occupant safety have included steel, glass-reinforced polypropylene, ABS, polycarbonate, and expanded bead foam such as polypropylene or SMA. As requirements increase and applications become more sophisticated, the benefits of polyurethane technology have made PU the top candidate for many of these applications. Increasingly, polyurethane foams are used because of their energy-absorbing properties over a wide temperature range, moldability, design flexibility, and low weight. Recent studies have focused on rigid crushable polyurethane foam, primarily for the knee impact application. However, polyurethanes can provide a broad range of foam types that offer energy management potential for a wide spectrum of design intents.

ICI Polyurethanes has developed a portfolio of new energy management (EM) polyurethane foam systems which are CFC-free, water-blown, and low density. These products range from rigid to semi-rigid to viscoelastic foams. Each type of foam offers unique properties for various automotive interior applications. Rigid foams absorb energy primarily through a non-recoverable, physical crushing of the foam cells. On the other hand, semi-rigid and viscoelastic foams provide a viscous dissipation of energy with a slow shape recovery. This paper describes the development, static/dynamic impact properties, and processing of these new polyurethane EM foams.