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Plastic pollution is a pressing issue because authorities struggle to contain and process the enormous amount of waste produced. We study the potential for reducing plastic waste by examining the efficiency with which different polyethylene terephthalate (PET) bottles deliver beverages. We find that 80% of the variation in bottle weight is explained by bottle capacity, 16% by product category, and 1% by brand. Bottle weight is quadratic and convex function of capacity, which implies that medium capacity bottles are most efficient at delivering consumable product. Local data on PET bottle sales and municipal waste recovery validate the findings. A 20% shift in consumption from smaller to larger bottles could reduce the production of PET waste by over 10,000 t annually in the U.S. alone.

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Big-leaf mahogany (Swietenia macrophylla) is valued for its high-quality wood and use in urban landscapes in Mexico. During surveys of mango-producing areas in the central western region of Mexico, symptoms of malformation, the most important disease of mango in the area, were observed on big-leaf mahogany trees. The objectives of this research were to describe this new disease and determine its cause. Symptoms on big-leaf mahogany at four sites in Michoacán, Mexico resembled those of the vegetative phase of mango malformation, including compact, bunched growth of apical and lateral buds, with greatly shortened internodes and small leaves that curved back toward the supporting stem. Of 163 isolates that were recovered from symptomatic tissues, most were identified as Fusarium pseudocircinatum (n = 121) and F. mexicanum (n = 39) using molecular systematic data; two isolates represented unnamed phylospecies within the F. incarnatum-equiseti species complex (FIESC 20-d and FIESC 37-a) and another was in the F. solani species complex (FSSC 25-m). However, only F. mexicanum and F. pseudocircinatum induced malformation symptoms on 14-day-old seedlings of big-leaf mahogany. The results indicate that F. mexicanum and F. pseudocircinatum, previously reported in Mexico as causal agents of mango malformation disease, also affect big-leaf mahogany. This is the first report of this new disease and the first time that F. mexicanum was shown to affect a host other than mango.

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The arbuscular mycorrhizal (AM) symbiosis is responsible for huge fluxes of photosynthetically fixed carbon from plants to the soil. Lipid, which is the dominant form of stored carbon in the fungal partner and which fuels spore germination, is made by the fungus within the root and is exported to the extraradical mycelium. We tested the hypothesis that the glyoxylate cycle is central to the flow of carbon in the AM symbiosis. The results of (13)C labeling of germinating spores and extraradical mycelium with (13)C(2)-acetate and (13)C(2)-glycerol and analysis by nuclear magnetic resonance spectroscopy indicate that there are very substantial fluxes through the glyoxylate cycle in the fungal partner. Full-length sequences obtained by polymerase chain reaction from a cDNA library from germinating spores of the AM fungus Glomus intraradices showed strong homology to gene sequences for isocitrate lyase and malate synthase from plants and other fungal species. Quantitative real-time polymerase chain reaction measurements show that these genes are expressed at significant levels during the symbiosis. Glyoxysome-like bodies were observed by electron microscopy in fungal structures where the glyoxylate cycle is expected to be active, which is consistent with the presence in both enzyme sequences of motifs associated with glyoxysomal targeting. We also identified among several hundred expressed sequence tags several enzymes of primary metabolism whose expression during spore germination is consistent with previous labeling studies and with fluxes into and out of the glyoxylate cycle.

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PURPOSE: The NICHD Fetal Cell Isolation Study (NIFTY) was a multicentered project to isolate fetal cells from maternal blood to detect fetal chromosomal abnormalities. The project included a psychosocial component, which is the basis of this article. We examined the attitudes of high-risk pregnant women toward the availability of a maternal blood test to identify fetal chromosomal abnormalities, how women would respond to hypothetical normal and abnormal maternal blood testing results, and the factors associated with a woman's preference to have an invasive procedure in response to a normal maternal blood test. METHODS: High-risk pregnant women (N = 854) planning to have prenatal diagnostic invasive testing (amniocentesis or chorionic villus sampling) completed a survey. RESULTS: The women highly favored maternal blood testing. Almost all women would seek invasive testing after an abnormal blood test. Only half of the women would seek invasive testing after a normal blood test; these women were older, more willing to terminate their pregnancy, and valued the increased accuracy of invasive testing more highly than women who would not have invasive testing after a normal maternal blood test. CONCLUSIONS: Women having invasive diagnostic testing welcome a noninvasive procedure that uses fetal cells in maternal blood, and its availability would decrease invasive testing by approximately 50%. Research needs to examine the attitudes and anticipated responses of other risk groups as well as the effects of information about maternal blood test sensitivity and specificity on attitudes and responses.

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BACKGROUND: The use of conventional cyclosporine (Sandimmune) requires great care, as this drug exhibits a narrow therapeutic index and wide interindividual variability in its pharmacokinetics. Recently, a new microemulsion formulation (Neoral) was developed. With this formulation, cyclosporine is absorbed at the small intestine without the presence of bile. Therefore, the objective of this study was to compare the bioavailability of cyclosporine after the administration of conventional and microemulsion formulations in healthy Mexican volunteers in order to approach the optimal dosage regimen of microemulsion in the Mexican population. METHODS: The trial was conducted using 23 healthy volunteers according to a randomized crossover design. Volunteers received one 7.5-mg/kg dose as each formulation, with a 1-week washout period between treatments. Blood samples of 0.5 mL were obtained according to the following schedule: 0, 0.5, 1, 2, 3, 4, 5, 6, 8, 12, and 24 h after medication. RESULTS: These indicated that Cmax and AUC0-24 values were higher with the microemulsion than with the conventional formulation. CONCLUSIONS: The microemulsion had a better absorption profile than the conventional formulation, because plasma levels with the conventional formulation demonstrated oscillations rather than reflecting an erratic absorption. Lower doses of the microemulsion are required to obtain Cmax values similar to those obtained with conventional cyclosporine.

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The increasing demands for accountability in higher education are resulting in calls for important personnel decisions--such as promotion, tenure, pay, and continuation--to be based directly on the outcomes of systematic faculty evaluations. This article provides a step-by-step procedure for developing a fair and meaningful faculty evaluation system on which such personnel decisions can be based. The procedure systematically involves faculty and administrators in the design and development of a faculty evaluation program that reflects the unique values, priorities, and heritage of an institution. The resultant faculty evaluation system integrates data from students, peers, and administrators to provide meaningful evaluative information for both faculty use in self-improvement efforts and administrative use in making personnel decisions that are based on a valid and reliable faculty performance record.

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The increased availability of telecommunications technology has made possible the offering of degree programs via distance education. Such programs make courses and degrees more readily accessible to a wider range of students than has traditionally been the case. The University of Tennessee, Memphis, College of Nursing has undertaken to offer a Master's of Science in Nursing degree entirely by distance education. The challenges, successes, and technology of the program are discussed.

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The purpose of the present study was to demonstrate the various applications of the laparoscopic surgery in the field of gynecology. 40 patients who were submitted to laparoscopic surgery were studied and divided into 5 groups accordingly to the surgical procedure: adhesiolysis, surgery of ovarian tumors, hysterectomy, surgery of the Fallopian tube and myomectomy. All the patients had a preoperative study and once completed they were selected for laparoscopic surgery. The laparoscopic procedure was able to solve the gynecologic pathology. The mean overall surgical time was of 66.8 min with a maximum time of 180 and a minimum of 30 min, accordingly to the groups the surgical mean times were as follows: 1) adhesiolysis 111 min 2) ovarian surgery 69 min 3) hysterectomy 113 min 4) tubal surgery 60 min and 5) myomectomy 58 min. There were no surgical complications and they all had a brief hospitalization period and a fast return to active life. All procedures were done with a bipolar cautery. We conclude that laparoscopic surgery is a useful resource for the resolution of the majority of the benign gynecologic pathology and when indicated in the proper way there is no rise in the morbid-mortality, and offers a short hospitalization period and a quick return to active life.

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The cervical infection by human papilloma virus (HPV) is considered one of the most common sexual transmitted diseases. Fifty couples were studied which consulted for sterility, in all women a cervical HPV infection was detected. Colposcopy, cervical biopsy, vaginal secretions culture, hysterosalpingography, laparoscopy and semen analysis were performed, in all of them. Age, obstetrical history, age at which patients began sexual relations, number of sexual partners, usage and time of usage of intrauterine device were analyzed. We can conclude that patients HPV cervical infection have risk factors for tuboperitoneal sterility, and are also in risk for other sexual transmitted diseases.

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A case of a 27-year-old woman with a previous partial uterine dearterialization for uterine atony in its first gestation, is presented. This woman asked advise for secondary infertility and after a laparoscopic adhesiolysis she achieved pregnancy. With the exception of tubo-peritoneal factor all other infertility studied factors were normal. Partial uterine dearterialization must be taken in account in patients with obstetric bleeding and posterior fertility expectatives.

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Forty-nine laparoscopic findings of women with chronic pelvic pain and dysmenorrhea, were reviewed. In all of them a laparoscopy was performed under general anesthesia. Endometriosis was found as principal cause of the pain, followed by chronic pelvic inflammatory disease and adhesions. In 10.2% of the patients the pelvis was normal. We can conclude that in the patient with chronic pelvic pain, laparoscopy is a useful method to achieve the correct diagnosis to prescribe the most accurate treatment.

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Uridine diphosphate glucose pyrophosphorylase (UDPGPP) is the first enzyme in the bilirubin conjugation pathway. A study aiming to screen for red blood cell UDPGPP deficiency in newborns with hyperbilirubinemia was carried out. No individuals with severe UDPGPP deficiency were found, however, levels of UDPGPP in premature and at term newborns were lower than in adults. These findings led to the study of UDPGPP in human fetal, neonatal and adult liver, using guinea pig tissues as a parallel control. UDPGPP activities in fetal and neonatal samples were also significantly lower than in adult ones in both species. Therefore, it is postulated that the reduced levels of UDPGPP in fetal and neonatal liver could be a factor which contributes to the pathogenesis of the physiologic jaundice in human newborns.

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Quantitative screening for red blood cell sorbitol dehydrogenase (RBC-SORD) deficiency in 111 patients with juvenile onset diabetes, 92 patients with adult onset diabetes, 42 patients with idiopathic cataracts and 192 professional blood donors was performed. A wide variability in RBC-SORD activity in controls and patients was observed. No significant differences in SORD activity either between patients with diabetes and patients with idiopathic cataracts or between diabetics with and without cataracts were observed. Whether or not there were carriers for either amorphous or hypomorphous alleles of the SORD locus in the population studied could not be defined in terms of enzymatic activity levels.

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A 3-year-old girl was found to have a 3qter trisomy resulting from a de novo t(X;3)(p22.3;q25.3) with a mild expression of the imbalance. Replication studies revealed a late replicating der (X) in 86% of the scored lymphocytes with variable patterns of inactivation of the 3q segment.

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A 10-month-old girl with growth and psychomotor retardation and pyramidal signs, was found to have a 47,XX,inv(9)(p11q13),+i(18p) karyotype. Whereas the inverted chromosome was inherited from the father, the isochromosome was of unknown origin. A comparative analysis with 17 similar cases from the literature lead to the conclusion that the tetrasomy 18p actually constitutes a distinctive syndrome.

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Se estimaron la concentracion de deshidrogenasa C4 de lactato (LDH-C4) en plasma seminal humano y su relacion con el numero de espermatozoides totales, viables y muertos por mililitro en muestras de dos o tres diferentes eyaculaciones de 55 individuos clinicamente sanos, obtenidas despues de un periodo de abstinencia de cuando menos tres dias, y en intervalos de un mes. Los resultados mostraron una correlacion positiva y significativa entre la concentracion de LDH-C4 y el numero de celulas totales y de celulas viables (r= 0.3668 con p < 0,0l, y r= 0.3729 con p < 0.01, respectivamente), y positiva pero no significativa en relacion con el numero de celulas muertas (r= 0.2065, p = n.s.). El analisis del intervalo de confianza al 99 por ciento de la ecuacion de regresion lineal del numero de celulas totales y de celulas viables versus LDH-C4 mostro la exclusion del 51 por ciento de los casos, lo que sugiere que la concentracion de LDH-C4 presente en el plasma seminal depende de factores adicionales a la densidad espermatica y a la viabilidad celular

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Se determinaron los niveles sericos, de los acidos biliares colilglicina y sulfolitocolilglicina, por radioinmunoanalisis en varias enfermedades hepatobiliares como son: cirrosis secundaria a alcoholismo, cirrosis post-hepatitis, colestasis extrahepatica, absceso hepatico amibiano, hepatitis cronica activa y un grupo miscelaneo. La colilglicina se elevo principalmente, en aquellos padecimientos que cursaban con alteraciones hepatocelulares y obstruccion extrahepatica; los valores mas altos se observaron en pacientes con cirrosis hepatica secundaria a alcoholismo que cursaban con encefalopatia y en aquellos con obstruccion maligna. La sulfolitocolilglicina solo se incremento en la obstruccion extrahepatica por lo que se considera mas especifica y posiblemente de utilidad, para el diagnostico diferencial de colestasis. Se discuten las posibles causas que pueden intervenir en la elevacion de estos acidos biliares en los padecimientos hepatobiliares

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