Terminal (1)(q43) long-arm deletion of chromosome no. 1 in a three-year-old female

A 3-year-old Latin female is reported with a terminal deletion of the No. 1 chromosome, karyotype formula 46, XX, del(1) (q43). Principle clinical features include: Anatomic - microcephaly; bilateral, convergent strabismus; epicanthus; brachycephaly; bulbar nose; sparse hair; partial soft tissue syndactylism between 2nd and 3rd fingers which are slightly tapered; whorls on all 10 fingers; mild prognathism; solitary kidney; vaginal stenosis; vesicoureteral reflux; asymmetric feet; and subluxation of peroneal tendons around the fibula with severe pronation and heal valgus deformity. Neurologic - moderate motor and mental retardation; high-pitched, shrill cry; absent pincer grasp at 3 years; and grand mal seizures documented from 9 months of age.     

Dilute solution properties of randomly branched poly(methyl methacrylate)

Randomly branched poly(methyl methacrylate) samples were prepared by copolymerization with different amounts of ethylene dimethacrylate. The molecular weight distributions, radius of gyration distributions, and intrinsic viscosity distributions were measured by size exclusion chromatography with refractive index, multiangle light-scattering, and viscosity detectors. The effect of branching on the radius of gyration was compared with the effect on the intrinsic viscosity. It was found that the intrinsic viscosity contraction factor gⁱ scales with the radius of gyration contraction factor g, with the exponent, ϵ, having a value in the range 0.8–1.0. © 1996 John Wiley & Sons, Inc.     

NO/cGMP pathway is involved in exocrine secretion from rat pancreatic acinar cells

OBJECTIVE: To identify factors associated with the initiation of breast-feeding in a predominantly Puerto Rican population living in inner-city Hartford, Conn. DESIGN: Retrospective study of 144 Latino women (mean +/- standard deviation age = 26.3 +/- 5.7 years) with children at least 1 year old but younger than 6 years old (mean +/- standard deviation age = 3.0 +/- 1.2 years) at the time of the survey. Women were recruited from agencies sponsoring health programs for mothers and children. They were interviewed in their homes (69%) or at the Hispanic Health Council, Hartford, Conn (31%). SUBJECTS/SETTING: Low-income Latino women who had at least 1 preschooler at the time of the interview. The women lived in inner-city Hartford, and the overwhelming majority were Puerto Rican and received welfare assistance and food stamps. Seventy-eight percent of the women chose to be interviewed in Spanish; the other 22% were interviewed in English. STATISTICAL ANALYSES: Explanatory variables that related to breast-feeding initiation (P < or = .2) in bivariate chi 2 analyses were entered into a multivariate logistic regression model that was reduced using backward stepwise elimination procedures. RESULTS: Multivariate analyses indicated that breast-feeding the previous child, shorter length of maternal residence in the United States, not receiving prenatal bottle-feeding advice, more recent birth, and higher birth weight were positively associated with breast-feeding initiation. A major reason for choosing not to breast-feed was that women felt socially uncomfortable doing it. APPLICATIONS: Breast-feeding initiation was more likely in Latino women who received prenatal breast-feeding counselling and postpartum support. Mothers of low-birth-weight infants and women breast-feeding for the first time may need additional help. These findings can be used by programs like the Special Supplemental Nutrition Program for Women, Infants, and Children to increase breast-feeding initiation.     

Polymer electrolyte membranes from fluorinated polyisoprene-block-sulfonated polystyrene: Structural evolution with hydration and heating

Small-angle neutron scattering (SANS) and ultra-small-angle X-ray scattering (USAXS) have been used to study the structural changes in fluorinated polyisoprene/sulfonated polystyrene (FISS) diblock copolymers as they evolved from the dry state to the water swollen state. A dilation of the nanometer-scale hydrophilic domains has been observed as hydration increased, with greater dilation occurring in the more highly sulfonated samples or upon hydration at higher temperatures. Furthermore, a decrease in the order in these phase separated structures is observed upon swelling. The glass transition temperatures of the fluorinated blocks have been observed to decrease upon hydration of these materials, and at the highest hydration levels, differential scanning calorimetry (DSC) has shown the presence of tightly bound water. A precipitous drop in the mechanical integrity of the 50% sulfonated materials is also observed upon exceeding the glass transition temperature (T_g), as measured by dynamic mechanical analysis (DMA).     

Yield stress distribution in injection‐moulded glassy polymers

A methodology for structural analysis simulations is presented that incorporates the distribution of mechanical properties along the geometrical dimensions of injection‐moulded amorphous polymer products. It is based on a previously developed modelling approach, where the thermomechanical history experienced during processing was used to determine the yield stress at the end of an injection‐moulding cycle. Comparison between experimental data and simulation results showed an excellent quantitative agreement, both for short‐term tensile tests as well as long‐term creep experiments over a range of strain rates, applied stresses, and testing temperatures. Changes in mould temperature and component wall thickness, which directly affect the cooling profiles and, hence, the mechanical properties, were well captured by the methodology presented. Furthermore, it turns out that the distribution of the yield stress along a tensile bar is one of the triggers for the onset of the (strong) localization generally observed in experiments. © 2015 Society of Chemical Industry     

Synthesis and chain flexibility of poly(cyclohexylethyl methacrylate)

The synthesis and characterization of fractions of poly(cyclohexylethyl methacrylate) (PCHEM) are reported. A combination of low-angle laser light scattering and intrinsic viscosity experiments was employed to estimate the characteristic ratio (C_∞) of this polymer. The value of 10.7 obtained for PCHEM is similar to the value of 11.3 found previously for poly(phenylethyl methacrylate) but is smaller than values measured for poly(cyclohexyl methacrylate) and poly(cyclohexylmethyl methacrylate) (C_∞ = 11.6 and 11.9, respectively). Received: 28 October 1996/Revised: 16 December 1996/Accepted: 19 December 1996