bluuebunny/crossref_metadata_2025_split huggingface dataset:
Teachers' comfort and importance ratings for interventions for preschoolers with AD/HD
Authors: Stormont Melissa , Stebbins Molly S. 
Published: August 2002

AbstractThe main purpose of this study was to explore preschool teachers' ratings of both the perceived importance of and their comfort levels implementing interventions for children with AD/HD. Participants included 138 teachers from licensed child care facilities. Teachers completed a questionnaire that required them to rate, on a 7‐point Likert‐type scale, the importance of 43 interventions and how comfortable they would be executing the strategy if asked to do so in the classroom. Overall, teachers concluded that the majority of the interventions were mostly important and believed they would be comfortable using the strategies. In addition, findings indicated that preschool teachers' importance and comfort ratings were highly correlated. Teacher variables (i.e., years of teaching experience, educational level, and having a student with AD/HD) were not correlated with, or discriminative of, comfort and importance ratings. The implications of these findings are discussed. © 2001 John Wiley & Sons, Inc.
Kinetics and mechanisms of solvolysis of 3‐chloro‐3‐ethylpentane in alcohols as solvents. Application of multiparametric equations and factor analysis to the solvolytic reactions of tert‐alkyl halides
Authors: Albuquerque Lídia M. P. C. , Moita M. Luísa C. J. , Gonçalves Raquel M. C. 
Published: August 2002

AbstractThis paper introduces a new set of rate constants for solvolysis of 3‐chloro‐3‐ethylpentane in eight monoalcohols, from methanol to 2‐methylbutan‐1‐ol, and in 10 dialcohols, from ethane‐1,2‐diol to pentane‐1,5‐diol, and also in diethylene and triethylene glycol. These results together with previous obtained data for several solvolytic reactions of tert‐alkyl halides (2‐iodo‐2‐methylpropane, 2‐bromo‐2‐methylpropane, 2‐chloro‐2‐methylpropane, 2‐bromo‐2‐methylbutane, 2‐chloro‐2‐methylbutane and 3‐chloro‐3‐methylpentane) in the same mono‐ and dialcohols were studied by means of a standard multiparametric approach and by target factor analysis (TFA). TFA provides an open criterion for selecting the quantity and nature of the possible causes of the variation in the rate constants. The results allow one to identify and quantify the dominant solute–solvent interaction mechanisms affecting the reactions. Solvent dipolarity, polarizability and hydrogen bond donor acidity are the main influences on reactivity, although mono‐ and dialcohols behave differently. Copyright © 2001 John Wiley & Sons, Ltd.
Novel functional initiators for oxazoline polymerization
Authors: Einzmann Mirko , Binder Wolfgang H. 
Published: August 2002

AbstractThe initiating behavior of the functional tosylates 1–4 and triflates 5 and 6 for the cationic ring‐opening polymerization of 2‐methyl‐1,3‐oxazoline was investigated. The emphasis was directed at tosylates and triflates with 2,2‐dimethyl‐1,3‐dioxolane‐, 2,3‐epoxypropyl‐, 2,3‐didodecanoyl‐glycerol‐, and cholest‐5‐en‐moieties that allow the construction of amphiphilic polyoxazoline conjugates. The tosylates were prepared by a simple reaction of the corresponding alcohols with p‐toluenesulfonyl chloride, whereas the preparation of the corresponding triflates required low temperature and the use of 2,6‐di‐tert‐butylpyridine as a sterically hindered base. Among the initiators tested, 2,2‐dimethyl‐(4‐trifluoromethanesulfonyloxymethyl)‐1,3‐dioxolane 6 gave the best results in respect to molecular weight and polydispersity. Starting from the corresponding functional oxazoline polymers obtained with 6 as an initiator, amphiphilic lipid‐polyoxazoline conjugates with a diacylglycerol backbone could be prepared. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2821–2831, 2001
Controlled free‐radical polymerization of 2‐vinylpyridine in the presence of nitroxides
Authors: Chalari Ioanna , Pispas Stergios , Hadjichristidis Nikos 
Published: August 2002

AbstractBulk free‐radical polymerization of 2‐vinylpyridine (2VP) in the presence of 2,2,6,6‐tetramethylpiperidine‐N‐oxyl (TEMPO) was studied under different conditions (temperature and presence of additives). Linear poly‐(2‐vinylpyridine) with a narrow molecular weight distribution and controllable molecular weight was prepared in the presence of acetic anhydride at 95 °C up to a conversion of 66%. At higher conversions side reactions became very important (pseudoliving polymerization). By applying this procedure, well‐defined random copolymers of 2VP with styrene or tert‐butylmethacrylate as well as block copolymers of 2VP with styrene were synthesized. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2889–2895, 2001
Poly(ethylene terephthalate) copolyesters derived from (2S,3S)‐2,3‐dimethoxy‐1,4‐butanediol
Authors: Kint Darwin P. R. , Wigström Emilia , de Ilarduya Antxon Martínez , Alla Abdelilah , Muñoz‐Guerra Sebastián 
Published: August 2002

AbstractNovel poly(ethylene terephthalate) (PET) copolyesters, abbreviated PEDMBT, containing optically active (2S,3S)‐2,3‐dimethoxy‐1,4‐butanediol (DMBD) as the second comonomer were investigated. Copolymers with ethylene glycol to DMBD ratios between 95/5 and 50/50 as well as the two parent homopolymers, PET and PDMBT, were prepared by a two‐step melt polycondensation. The resulting copolymers were found to approximately have the composition of the polymerization reaction feed and a random microstructure. Polymer intrinsic viscosities varied from 0.4 to 0.6 dL g−1 with weight‐average molecular weights ranging from 16,000 to 44,000. PEDMBT copolyesters were distinguished in being much more soluble than PET and showing an increasing affinity for water with the content in dimethoxy groups. According to the asymmetric constitution of DMBD, they displayed optical activity in solution. Both melting and glass‐transition temperatures of the copolyesters were observed to steadily decrease with the content in DMBD. PEDMBTs were found to be crystalline for contents in DMBD up to 30 mol %. Both powder and fiber X‐ray diffraction revealed that the same crystalline structure is shared by PET and the crystalline copolyesters. The homopolyester PDMBT resulted in becoming a polymer with a crystallinity comparable to PET but with a significantly different crystalline structure. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3250–3262, 2001
Initial step of anthracene‐sensitized photoacid generation from diphenyliodonium hexafluorophosphate in an epoxy matrix studied by steady‐state and laser‐flash photolyses
Authors: Kura Hisatoshi , Fujihara Kan , Kimura Akira , Ohno Teruhisa , Matsumura Michio , Hirata Yoshinori , Okada Tadashi 
Published: August 2002

AbstractThe anthracene‐sensitized photodecomposition of diphenyliodonium hexafluorophosphate was studied in an epoxy matrix. From steady‐state photolysis, the generation of protons, which are considered to be the actual initiators of the polymerization of epoxides, was confirmed. In addition, 9‐phenylanthracene was detected as a main product from anthracene. From time‐resolved laser‐flash photolysis, a broad absorption band with a peak at about 500 nm was observed that was thought to be due to the precursor of 9‐phenylanthracene. On the basis of these results, we propose electron transfer from anthracene in the excited singlet state to the diphenyliodonium cation as the initial step of photoacid generation. This process is followed by fast chemical reactions, which generate 9‐phenylanthracene and protons, and back electron transfer from the diphenyliodine radical to the anthracene cation radical. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2937–2946, 2001
Microphase separation in poly(acrylonitrile–butadiene–styrene) (ABS) studied with paramagnetic spin probes. I. Electron spin resonance spectra
Authors: Varghese Biji , Schlick Shulamith 
Published: August 2002

AbstractMicrophase separation in poly(acrylonitrile–butadiene–styrene) (ABS) was studied as a function of the butadiene content and method of preparation with electron spin resonance (ESR) spectra of nitroxide spin probes. Results for the ABS polymers were evaluated by comparison with similar studies of the homopolymers polybutadiene (PB), polystyrene (PS), and polyacrylonitrile (PAN) and the copolymers poly(styrene‐co‐acrylonitrile) (SAN) and poly(styrene‐co‐butadiene) (SB). Two spin probes were selected for this study: 10‐doxylnonadecane (10DND) and 5‐doxyldecane (5DD). The probes varied in size and were selected because their hydrocarbon backbone made them compatible with the polymers studied. The ESR spectra were measured in the temperature range 120–420 K and were analyzed in terms of line shapes, line widths, and hyperfine splitting from the 14N nucleus; the appearance of more than one spectral component was taken as an indication of microphase separation. Only one spectral component was detected for 10DND in PB, PS, and PAN and in the copolymers SAN and SB. In contrast, two spectral components differing in their dynamic properties were detected for both probes in the three types of ABS samples studied and were assigned to spin probes located in butadiene‐rich domains (the fast component) and SAN‐rich domains (the slow component). The behavior of the fast component in ABS prepared by mass polymerization suggested that the low‐Tg (glass‐transition‐temperature) phase was almost pure PB. The corresponding phase in ABS prepared by emulsion grafting also contained styrene and acrylonitrile monomers. A redistribution of the spin probes on heating occurred with heating near the Tg of the SAN phase, suggesting that the ABS polymers as prepared were not in thermodynamic equilibrium. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 415–423, 2002; DOI 10.1002/polb.10109
Stress distribution in poly‐p‐phenylenebenzobisoxazole (PBO) fiber estimated from vibrational spectroscopic measurement under tension. II. Analysis of inhomogeneous stress distribution in PBO fiber
Authors: Kitagawa Tooru , Tashiro Kohji , Yabuki Kazuyuki 
Published: August 2002

AbstractFourier transform Raman spectra were measured for poly‐p‐phenylenebenzobisoxazole (PBO) fiber subjected to a tensile stress, and the Raman shift factor (the frequency shift caused by 1 GPa tensile stress) depended strongly on the sample‐preparation condition. To clarify the reasons of this dependency, a mechanical series parallel model was adopted that could successfully and quantitatively explain the observed Raman shift factors and gave a concreate heterogeneous stress distribution in the PBO fibers. As a result, a mechanical series model was reasonable for PBO fiber. Broadening of Raman bands, which was observed when the PBO fiber was tensioned, could also be interpreted on the basis of an idea of heterogeneous stress distribution. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 1281–1287, 2002
Compatibilizing effect of a graft copolymer on bacterial poly(3‐hydroxybutyrate)/poly(methyl methacrylate) blends
Authors: Ceccorulli Giuseppina , Scandola Mariastella , Adamus Grazyna 
Published: August 2002

AbstractBlends of isotactic (natural) poly(3‐hydroxybutyrate) (PHB) and poly(methyl methacrylate) (PMMA) are partially miscible, and PHB in excess of 20 wt % segregates as a partially crystalline pure phase. Copolymers containing atactic PHB chains grafted onto a PMMA backbone are used to compatibilize phase‐separated PHB/PMMA blends. Two poly(methyl methacrylate‐g‐hydroxybutyrate) [P(MMA‐g‐HB)] copolymers with different grafting densities and the same length of the grafted chain have been investigated. The copolymer with higher grafting density, containing 67 mol % hydroxybutyrate units, has a beneficial effect on the mechanical properties of PHB/PMMA blends with 30–50% PHB content, which show a remarkable increase in ductility. The main effect of copolymer addition is the inhibition of PHB crystallization. No compatibilizing effect on PHB/PMMA blends with PHB contents higher than 50% is observed with various amounts of P(MMA‐g‐HB) copolymer. In these blends, the graft copolymer is not able to prevent PHB crystallization, and the ternary PHB/PMMA/P(MMA‐g‐HB) blends remain crystalline and brittle. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 1390–1399, 2002
Respiratory mechanics in very low birth weight infants during continuous versus intermittent gavage feeds
Authors: Brar Gamdur , Geiss Donna , Brion Luc P. , Rios Angel 
Published: August 2002

AbstractThis study was designed to determine whether respiratory mechanics in stable, very low birth weight infants changed after replacing intermittent feeds with continuous feeding. We measured static respiratory system compliance, respiratory system resistance, functional residual capacity (FRC), and tidal volume immediately before feeds and at 20, 60, and 120 min after feeds, and again the next day on continuous feeds. Patients selected for enrollment into the study needed to fulfill the following criteria: 1) birth weight and postnatal weight < 1,500 g, 2) no need for mechanical ventilation, positive airway pressure, or supplemental oxygen, 3) receiving and tolerating at least 100 mL/kg/day of intermittent gavage feeds, and 4) no change in methylxanthine or diuretic dosage for 3 days before the study. Respiratory mechanics were measured using the SensorMedics 2600 Pediatric Pulmonary Cart (Yorba Linda, CA). We studied 16 infants (gestational age 28.3 ± 3.7 weeks, mean ± SD) at a postnatal age of 10–82 days.The average interindividual coefficient of variance was 20 ± 2% for static compliance, 35 ± 6% for resistance, 18 ± 3% for FRC, and 19 ± 3% for tidal volume. Repeated‐measures analysis of variance did not reveal any significant difference in respiratory mechanics with intermittent vs. continuous feeding.The data suggest that static respiratory mechanics in stable, very low birth weight infants are not affected by changing enteral feeds from intermittent gavage to a continuous schedule. Pediatr Pulmonol. 2001; 32:442–446. © 2001 Wiley‐Liss, Inc.
Management of oxygenation in pediatric acute hypoxemic respiratory failure
Authors: Matthews Benjamin D. , Noviski Natan 
Published: August 2002

AbstractThe prognosis for patients with acute respiratory distress syndrome (ARDS) in adults and children has improved since its formal acceptance as a clinical entity in 1967. Because acute hypoxemic respiratory failure is the hallmark of acute lung injury and ARDS, the management of oxygenation is crucial. Physicians managing pediatric patients with acute lung injury or ARDS are faced with a complex array of options influencing oxygenation. Certain treatment strategies can influence clinical outcomes, such as a lung‐protective ventilation strategy that specifies a low tidal volume (6 mL/kg) and a plateau pressure limit (30 cm H2O) (Acute Respiratory Distress Network, N Engl J Med 2000;342:1301–1308). Other lung‐protective strategies such as different levels of positive end‐expiratory pressure, altered inspiratory:expiratory ratios, recruitment maneuvers, prone positioning, and extraneous gases or drugs may impact clinical outcomes but require further clinical study.This paper reviews state‐of‐the‐art strategies on the management of oxygenation in acute hypoxemic respiratory failure and attempts to guide pediatric pulmonologists in managing children with respiratory failure. Pediatr Pulmonol. 2001; 32:459–470. © 2001 Wiley‐Liss, Inc.
Airway compression following thymus hyperplasia in an infant with Pierre Robin sequence and congenital diaphragmatic hernia
Authors: Hentschel R. , Willital G. , Hülskamp G. , Rieger C. 
Published: August 2002

AbstractA female infant with respiratory embarrassment due to external compression of the tracheobronchial tree by the thymus is presented. After successful intrauterine drainage of pleural effusions, she was born with a diaphragmatic hernia and Pierre Robin sequence, which required long‐term mechanical ventilation and several surgical interventions, including tracheostomy, until she breathed spontaneously. At age 7 months, she was rehospitalized in respiratory failure because of pneumonia. At this time, thymus hyperplasia was first diagnosed, which had caused tracheobronchomalacia and displacement of the tracheobronchial tree. Weaning from the ventilator was unsuccesful for 8 weeks. She underwent thymectomy, following which impairment of breathing resolved immediately. Different manifestations of thymus enlargement and their relation to impaired breathing are discussed. Pediatr Pulmonol. 2001; 32:476–479. © 2001 Wiley‐Liss, Inc.
Proliferation of prostate cancer cells in the bone marrow predicts recurrence in patients with localized prostate cancer
Authors: Bianco Fernando J. , Wood David P. , de Oliveira Jose Gomes , Nemeth Jeffrey A. , Beaman Andrew A. , Cher Michael L. 
Published: August 2002

AbstractBackgroundReverse‐transcription polymerase chain reaction (RT‐PCR) amplification of prostate specific antigen (PSA) mRNA has been used to detect the presence of prostate cancer cells in the peripheral blood and bone marrow of patients with clinically localized disease. Some studies have demonstrated a correlation between detection of PSA‐mRNA and disease recurrence. However, many RT‐PCR‐positive patients remain disease‐free. We propose that phenotypic characterization of individual micrometastatic cells may provide more prognostic information than mere detection of such cells.MethodsWe studied 58 patients undergoing radical prostatectomy for clinically localized disease whose bone marrow had been found to contain PSA‐mRNA by RT‐PCR. Immunohistochemical detection and phenotypic characterization of micrometastatic cells was performed using a two‐color technique: cytokeratin antibody for detection and the MIB‐1 antibody for proliferation. The clinical endpoint was disease recurrence.ResultsOne or more micrometastatic cells were proliferating in 36.2% of the patients; the disease‐free survival rate was 76.2% in this group. In contrast, in the patients with non‐proliferating cells, 97.3% remained disease‐free (P = 0.025). Multivariate analysis demonstrated that the presence of proliferating cells was the only preoperative variable that correlated with disease‐free survival (P = 0.05).ConclusionsDetermination of the phenotype of individual micrometastatic cells can contribute prognostic information above and beyond the mere determination of their presence or absence. Phenotypic characterization of individual micrometastatic cells may ultimately be used to select patients for systemic therapy given either alone or in combination with local therapy. Prostate 49:235–242, 2001. © 2001 Wiley‐Liss, Inc.
Anoikis is regulated by BCL‐2‐independent pathways in human prostate carcinoma cells
Authors: Bondar Victor M. , McConkey David J. 
Published: August 2002

AbstractBackgroundLoss of contact with the extracellular matrix (ECM) triggers a specialized form of apoptosis known as “anoikis” in normal epithelial cells. Dependence on adhesion to ECM is often lost in transformed cells, and the degree of anchorage independence may vary in non‐metastatic and metastatic cancer cells. BCL‐2 oncoprotein overexpression correlates with the progression and metastases of prostate cancer.Materials and MethodsWe studied anoikis in suspension cultures of PC‐3 and LNCaP prostate carcinoma cells selected for enhanced metastatic potential in vivo and in PC‐3 and LNCaP cells stably transfected with BCL‐2. Apoptosis‐associated DNA fragmentation was measured by agarose gel electrophoresis and propidium iodide staining and flow cytometry. Expression of BCL‐2 family polypeptides was determined by immunoblotting.ResultsNon‐metastatic PC‐3P cells were significantly more sensitive to anoikis than the metastatic PC‐3 variants (PC‐3M, PC‐3M‐PRO‐4, and PC‐3M‐LN‐4), but anoikis resistance did not correlate with metastatic potential in LNCaP‐derived cell lines. Expression of BCL‐2 was higher in metastatic PC‐3 and LNCaP subclones compared to isogenic non‐metastatic cells, but these levels were not affected by anoikis. Enforced overexpression of BCL‐2 did not protect either PC‐3P or LNCaP‐PRO‐5 cells from anoikis, even though it rendered them resistant to thapsigargin and inhibited cytochrome c release. Strikingly, cells that died of anoikis maintained their pretreatment levels of BCL‐2, whereas the cells that survived anoikis expressed much lower levels of the protein.ConclusionsSensitivity to anoikis is regulated by BCL‐2 independent mechanisms in LNCaP and PC‐3 prostate cancer cells. Prostate 51:42–49, 2002. © 2002 Wiley‐Liss, Inc.
PRAC: A novel small nuclear protein that is specifically expressed in human prostate and colon
Authors: Liu Xiu Fen , Olsson Pär , Wolfgang Curt D. , Bera Tapan K. , Duray Paul , Lee Byungkook , Pastan Ira 
Published: August 2002

AbstractBACKGROUNDThe database of human Expressed Sequence Tags (dbEST) provides a potential source for identification of tissue‐specific genes. This database contains sequences that originate from cDNA libraries from particular tumors, organs or cell types. In this report, we have used the EST database to identify PRAC, a novel gene specifically expressed in human Prostate, prostate cancer, Rectum And distal Colon.METHODSUsing a computer based analysis, a cluster of sequence homologous ESTs was identified which contained ESTs derived only from human prostate cDNA libraries. The tissue specificity was examined by multiple tissue RNA dot blots and RT‐PCR. The PRAC transcript and protein was identified using Northern blot analysis, RACE‐PCR, primer extension, and western blot.RESULTSPRAC encode a 382 nucleotide RNA found in prostate, rectum, distal colon, and in three prostate cancer cell lines; LNCaP, PC‐3 and DU145. This transcript encodes a 6 kDa nuclear protein. The PRAC gene is located on chromosome 17 at position 17q21, about 4 kbp downstream from the homeodomain Hoxb‐13 gene.CONCLUSIONSOur data proves that the EST database can be a useful tool for discovery of prostate‐specific genes. The nuclear localization, identification of potential phosphorylation sites, and possible cotranscription with the Hoxb‐13 gene suggest that PRAC may have a regulatory role in the nucleus. Prostate 47:125–131, 2001. © 2001 Wiley‐Liss, Inc.