cssi/SciSciGPT-SciSciNet huggingface dataset:
An investigation of metal matrix composites as shields for hypervelocity orbital debris impacts

Abstract The improvement of space vehicle shield designs to resist penetration by hypervelocity impacts of meteoroids or man-made orbital debris can lengthen mission life and increase mission efficiency. One option to improve shields is to create new bumper materials which can be tailored to meet the requirements for effective shielding. Metal matrix composites are one such material. Fiber content, type, and orientation could be varied to tailor the material to the specific properties needed for weight efficient shielding. In this study, two varieties of aluminum matrix composites were investigated, one with continuous graphite fibers and one with silicon carbide particulates. The objectives of the study were: to compare the penetration resistance of the composite with the known resistance of aluminum; to study the penetration mechanics by comparing the condition of the composite after the impact test with the pre-test condition; to study the effects of fiber content and fiber orientation on penetration resistance; and to recommend a material “design” for metal matrix composites which would best protect a space vehicle from orbital debris. The composite bumpers did not perform significantly better than aluminum bumpers. The particulate composites are more effective bumpers than the continuous fiber composites for the conditions tested. The differences in the measured hole diameters resulting from the impact tests as compared to predicted hole diameters for the particulate composite bumpers, are within the expected differences for metallics. However, the continuous fiber composites had much larger holes than predicted.
Compactness methods in the theory of homogenization II: Equations in non-divergence form

We prove C0, α, C1, α and C1, 1 a priori estimates for solutions of boundary value problems for elliptic operators with periodic coefficients of the form Σ,j=1ai j(x/ϵ)δ2/δxiδxj. The constants in these estimates are independent of the small parameter ϵ, and hence our results imply strengthened versions of the classical averaging theorems. These results generalize to a wide class of linear operators in non-divergence form, including equations with lower-order terms and nonuniformly oscillating coefficients, as well as to certain nonlinear problems, which we discuss in the last section.
The advantage of live-donor kidney transplantation in older recipients

Although renal transplantation confers a survival advantage over maintenance dialysis in patients with end-stage renal disease, many factors can attenuate this survival advantage over the long term. Among the most important negative influences on outcomes are older donor age, extended time on the transplant waiting list, and use of organs from deceased donors. Whether it is better to avoid prolonged waiting times for a standard criteria donor kidney by transplanting an organ from an older living donor is a clinically important question. In their analysis, Gill and colleagues have addressed this question for older transplant recipients. The investigators' primary finding is that survival after transplantation from an older living donor is at least equivalent to that after transplantation from a younger deceased donor (i.e. a standard criteria donor) and superior to that observed following transplantation from expanded criteria donors. Reasons that prevent a straightforward clinical application of such findings are discussed in this commentary.
Splits and Gaps in Buddhism and Postmodern Theology

De serieux desaccords existent a l'interieur du bouddhisme et de la theologie postmoderne au sujet de la nature du vide. L'A. s'interesse aux similitudes entre ces desaccords. Les differences sur l'approche du vide entre Taylor et Altizer peuvent etre comparees a celles qui existent entre les bouddhistes au sujet de la sūnyatā, c'est a dire les lectures positives ou negatives de l'elevation dependante. La premiere partie s'attache aux desaccords du cote bouddhiste. La seconde partie se place du cote de la theologie postmoderne. La troisieme partie suggere qu'il existe un deficit dans les deux points de vue et qu'une troisieme lecture peut intervenir
Carbon-13 magnetic resonance of coal-derived liquids

Abstract Carbon-13 Nuclear Magnetic Resonance Spectroscopy has been applied to coal-derived liquids in order to obtain additional information regarding molecular structure and composition. The data have demonstrated that, although the chemical structure is extremely complex, a significant amount of material is present in the form of normal paraffinic material both as free paraffins and alkyl substituents on aromatic and hydroaromatic materials. Semiquantitative estimates are made of the alkyl content of the liquids and the atom percentage of this material that must exist in the unprocessed coal.
Can We Talk? Fostering Interchange Between Scientists and Practitioners

In response to three surveys of (mostly) cognitive-behavioral practitioners about barriers to treatment success with cognitive-behavioral therapy for patients with generalized anxiety disorder, panic disorder, and social phobia (McAleavey, Castonguay, & Goldfried, 2014-this issue; Szkodny, Newman, & Goldfried, 2014-this issue; Wolf & Goldfried, 2014-this issue), the author proposes several methods for tapping clinical expertise in the development and dissemination of psychological interventions. These include: following surveys with interviews of a subset of clinicians to obtain richer information, systematically incorporating answers to questions and problems trainees raise in supervision in efficacy or effectiveness trials, organizing clinical roundtables at meetings of the Association for Behavioral and Cognitive Therapies to discuss ways to address barriers identified in these surveys, and encouraging papers on these topics in Cognitive and Behavioral Practice. At the same time the author emphasizes that clinical observations are not facts and need to be verified in empirical research.
The in vivo glucocorticoid and antiglucocorticoid actions of medroxyprogesterone acetate.

The in vivo glucocorticoid actions of medroxyprogesterone acetate [6α-methyl-17-acetoxy-pregn-4-ene-3,20 dione (MPA)] were assessed in intact prepubertal female Wistar rats using five simultaneous assays: plasma glucose, plasma corticosterone, hepatic glycogen content, hepatic tyrosine aminotransferase activity, and croton oil-induced ear inflammation. Antiglucocorticoid activity was measured through interference by MPA with the glucocorticoid effect of a standard 5-μg dose of dexamethasone in these same assays. The glucocorticoid activity of MPA was evident from suppression of corticosterone and ear inflammation and stimulation of tyrosine aminotransferase activity. The antiglucocorticoid activity of MPA was detected through inhibition of basal and dexamethasone-stimulated hepatic glycogen and partial reversal of the suppression of ear inflammation by dexamethasone. The progestational steroid MPA was thus found to have assay-specific glucocorticoid and antiglucocorticoid actions and may have a potential ...
Preparation and vulcanization of liquid polyisoprene polymers

By means of chain transfer agents such as dodecyl mercaptan, polyisoprenes whose number-average molecular weights range between 300-1200 and which are liquid at room temperature have been prepared. The structure and physical properties of these substances have been investigated. Vulcanization of these liquids to rubberlike materials at room temperature and above is described.
Autophagy Is Disrupted in a Knock-in Mouse Model of Juvenile Neuronal Ceroid Lipofuscinosis

Juvenile neuronal ceroid lipofuscinosis is caused by mutation of a novel, endosomal/lysosomal membrane protein encoded by CLN3. The observation that the mitochondrial ATPase subunit c protein accumulates in this disease suggests that autophagy, a pathway that regulates mitochondrial turnover, may be disrupted. To test this hypothesis, we examined the autophagic pathway in Cln3Δex7/8 knock-in mice and CbCln3Δex7/8 cerebellar cells, accurate genetic models of juvenile neuronal ceroid lipofuscinosis. In homozygous knock-in mice, we found that the autophagy marker LC3-II was increased, and mammalian target of rapamycin was down-regulated. Moreover, isolated autophagic vacuoles and lysosomes from homozygous knock-in mice were less mature in their ultrastructural morphology than the wild-type organelles, and subunit c accumulated in autophagic vacuoles. Intriguingly, we also observed subunit c accumulation in autophagic vacuoles in normal aging mice. Upon further investigation of the autophagic pathway in homozygous knock-in cerebellar cells, we found that LC3-positive vesicles were altered and overlap of endocytic and lysosomal dyes was reduced when autophagy was stimulated, compared with wildtype cells. Surprisingly, however, stimulation of autophagy did not significantly impact cell survival, but inhibition of autophagy led to cell death. Together these observations suggest that autophagy is disrupted in juvenile neuronal ceroid lipofuscinosis, likely at the level of autophagic vacuolar maturation, and that activation of autophagy may be a prosurvival feedback response in the disease process.
Suture Materials and Suture Selection for Use in Exotic Pet Surgical Procedures

Exotic animals are becoming increasingly popular and more exotic pet owners are seeking veterinary care. This has led to a demand for properly trained veterinarians who are capable of providing quality, up-to-date medical and surgical treatments. Many surgeries are now performed on exotic pets, and selection of the appropriate suture material is an important part of the treatment protocol. An understanding of different available suture materials, healing times of different tissues, and knowledge of different anatomic and physiologic characteristics in different species is important in the selection of the most appropriate suture material. This review will summarize important aspects of suture selection in exotic animals.
Three-dimensional multifunctional hierarchical nanocomposites: multifunctional materials

Traditional 1-D and 2-D composite materials have excellent in-plane properties. However, they are susceptible to interlaminar crack and crack growth leading to delaminations and catastrophic failure of the composite structures. To remedy these problems, researchers have developed 3-D composites using through-the-thickness stitching and/or braiding. However, these two techniques have their own problems. For braiding, the part thickness should be known a priori, which is not practical. Besides the fiber architecture is not arranged orthogonally. For the stitching, it has been shown that while through-the-thickness properties increase, in-plane properties decrease. Here, we explain a novel technique, developed by the authors and co-workers, to develop 3-D multifunctional hierarchical nanocomposites with superior properties. In this approach, multi-walled carbon nanotubes (MWCNTs) are grown vertically over 2-D microfiber woven fabric cloth, without altering the 2-D cloth architecture, to create nano-forests coating of MWCNTs in the thickness direction to yield 3-D orthogonal fiber architechture. The 3-D nano-forest woven cloths are later impregnated with the resins and are subsequently stacked, vacuum bagged, and cured to give 3-D multifunctional hierarchical nanocomposites. Since MWCNTs have superior mechanical, thermal, and electrical properties, the hierarchically developed 3-D multifunctional nanocomposites have enhanced mechanical, thermal, thermomechanical, damping, and electrical properties by many folds.
Pneumocystis carinii: Growth variables and estimates in the A549 and WI-38 VA13 human cell lines

Recent studies indicate that rat Pneumocystis carinii can be propagated in the A549 cell line, an alveolar epithelioid cell line derived from human lung carcinoma. In the present study, growth of P. carinii was compared in the A549 cell line and the WI-38 VA13 subline 2RA, an SV40 transformed derivative of the human fetal fibroblast cell line with epithelioid morphology. Similar P. carinii growth occurred in both cell lines under optimal conditions, but the WI-38 VA13 cell line was usually more sensitive to changes in the culture system. Growth of P. carinii was affected by temperature, environmental gas mixture, motion of the cultures, and source and concentration of serum additives, but not by the presence of antibodies in the medium. A technique was developed for quantitating P. carinii in the lung inoculum which permitted analysis of P. carinii growth during the first 24 hr of culture. Inverted microscope and oil immersion phase-contrast microscopy were very helpful in monitoring the organism's stages of development and viability. Thus, this culture system should be helpful in establishing standard methodology for in vitro work with P. carinii.
Denitrification potential of epilithic communities in a lotic environment

Denitrification potentials of epilithic microbial populations were assessed using the acetylene inhibition method, in which acetylene is used to block the reduction of nitrous oxide (N2O) to nitrogen (N2). Samples of the epilithic community were incubated in filtered river water containing modified Bushnell-Haas salts, glycerol, and yeast extract—under aerobic (0.2 atm O2) and anaerobic (0.2 atm He) acetylene atmospheres. N2O was produced under both atmospheres only if exogenous nitrate of nitrite was added. Denitrification potentials were typically higher when nitrite was the added electron acceptor. The rates of denitrification were temperature-and carbon-dependent and the maximum rate, 8.53 μg N2O−N per cm2 per day occurred at 23°C when nitrite was the electron acceptor.
Large congenital melanocytic nevi and the risk for development of malignant melanoma and neurocutaneous melanocytosis.

Objective. To determine the risk for developing malignant melanoma and neurocutaneous melanocytosis (NCM) in patients with large congenital melanocytic nevi. Design. Follow-up data suitable for calculations were available on 160 patients in the New York University Registry of Large Congenital Melanocytic Nevi who had been free of known melanomas or NCM when entered into the Registry. The cumulative 5-year life-table risks for developing melanoma and NCM were calculated. The relative risk for developing melanoma, using a control general population reference group, was determined. Results. The 160 patients (median age at entry: 14 months) were followed prospectively for an average of 5.5 years. Three extracutaneous melanomas developed: 2 were in the central nervous system (CNS) and 1 was retroperitoneal. The 5-year cumulative life-table risk for developing melanoma was 2.3% (95% confidence interval [CI]: .8–6.6) and the relative risk was 101 (95% CI: 21–296). No melanoma occurred within a large congenital melanocytic nevus. Four patients developed manifest NCM, 2 with CNS melanomas. The 5-year cumulative life-table risk for developing NCM was 2.5% (95% CI: .8–7.2). Ten patients were excluded from the calculations because of preexisting disease on entry into the Registry: 5 with manifest NCM and 5 with melanomas (3 in large congenital melanocytic nevi, 1 in nonnevus skin, and 1 unknown primary). Conclusions. Patients with large congenital melanocytic nevi are at increased risk for developing melanomas. There is also a significant increased risk for developing NCM. The high incidence of CNS involvement may influence decisions concerning treatment of the large congenital melanocytic nevi.
Liver disease and parenteral nutrition in an adolescent with cystic fibrosis.

A 15-year-old female with cystic fibrosis (CF) was admitted to the hospital following a 7-day history of productive cough, shortness of breath, sore throat and malaise. Although the patient was diagnosed with CF at 2 years of age, her first hospitalization for a pulmonary exacerbation was not until age 13. Over the next 2 years, she developed rapidly progressive lung disease. The patient’s history was also complicated by CF-associated biliary cirrhosis (hypersplenism, modest hepatomegaly, portal hypertension and varices) that began with modestly elevated liver function tests at approximately 7 years of age. Eighteen days prior to the admission described in this case, she completed a course of home antibiotics. Forced Vital Capacity (FVC) and Forced Expiratory Volume in 1 second (FEV1) were 28% and 19% at admission. She was started on antibiotic therapy (ceftazidime 2 g IV q8h, tobramycin 130 mg IV q8h and colistimethate 75 mg q12h via nebulization). She was also receiving home medications which included ADEK vitamin 2 tablets qhs, omeprazole 20 mg bid, ursodiol 600 mg bid, pancreatic enzymes 5 tablets with meals and 2 tablets with snacks, beclomethasone 1 spray in each nostril bid, nadolol 10 mg (increased to 20 mg during this admission) bid; nebulization therapy with albuterol 0.5 ml tid, dornase alfa 2.5 mg qhs, and tobramycin 300 mg bid. Vest physical therapy was used in conjunction with nebulization treatments.
Cell renewal of glomerular cell types in normal rats. An autoradiographic analysis

Abstract Cell renewal of glomerular cell types in normal rats. An autoradiographic analysis. Normal adult Sprague-Dawley rats received either a single or repetitive injection of the DNA precursor 3 H-thymidine ( 3 H-TdR). For autoradiography semi-thin sections were prepared 2hr to 14 days after labeling. The majority of labeled cells noted in glomerular tufts were endothelial cells. Mesangial cells had a lower production rate. Podocytes revealed no evidence of proliferation. Bowman's capsule cells showed a higher labeling index than tuft cells at all times. Neither the urinary nor the vascular pole was found to be a proliferative zone for Bowman's capsule cells. The flash and repetitive labeling experiments demonstrated a constant rate of cell renewal of about 1% per day, resulting in a long life span for endothelial and mesangial cells as well as Bowman's capsule cells. These data provide a basis for cell kinetic studies in models of glomerular diseases. Renouvellement cellulaire des cellules glomerulaires chez des rats normaux. Une analyse autoradiographique. Des rats Sprague-Dawley adultes normaux ont recu une injection soit unique soit repetee du precurseur du DNA, la 3 H-thymidine ( 3 H-TdR). Pour l'autoradiographie des sections semi-fines ont ete preparees 2 heures a 14 jours apres le marquage. La majorite des cellules marquees notees dans les floculus glomerulaires etaient des cellules endotheliales. Les cellules mesangiales avaient une vitesse de production plus faible. Les podocytes n'ont pas revele de preuve de proliferation. Les cellules de la capsule de Bowman ont montre un plus grand index de marquage que les cellules du floculus a tous les temps. Ni le pole urinaire ni le pole vasculaire n'ont ete trouves etre une zone proliferative pour les cellules de la capsule de Bowman. Les experiences de marquage unique ou par repetition ont demontre une vitesse constante de renouvellement cellulaire d'environ 1% par jour, entrainant une longue duree de vie pour les cellules endotheliales et mesangiales, ainsi que pour les cellules de la capsule de Bowman. Ces donnees apportent une base pour des etudes de cinetique cellulaire dans des modeles de maladies glomerulaires.
FLUX CREEP IN TYPE-II SUPERCONDUCTORS.

We have made measurements of the evanescent decay of the irreversible magnetization induced by magnetic cycling of solid superconducting cylinders in order to elucidate the mechanisms of Anderson's thermally activated flux-creep process. A superconducting quantum interferometer device coupled to the creep specimen by a superconducting flux transformer made possible observations of flux changes with a resolution of one part in ${10}^{9}$. The general applicability of Anderson's theory of flux creep was confirmed and the results were analyzed to show that: (1) The total flux in the specimen changed logarithmically in time, i.e., $\ensuremath{\Delta}\ensuremath{\varphi}\ensuremath{\propto}\frac{\mathrm{ln}t}{{t}_{0}}$. (2) The logarithmic creep rate $\frac{d\ensuremath{\varphi}}{d\mathrm{ln}t}$ is proportional to the critical current density ${J}_{c}$ and to the cube of the specimen radius. (3) The logarithmic creep rate appears to be only weakly temperature-dependent because a proportionality to $T$ is nearly compensated by the proportionality to ${J}_{c}$, which decreases as $T$ increases. (4) The creep process is a bulk process that is not surface-limited (in this case). (5) Flux enters and leaves the surface in discrete events containing from about one flux quantum up to at least ${10}^{3}$ flux quanta. (6) On departing from the critical state to a subcritical condition, the creep process tends to remain logarithmic in time, but the rate is decreased exponentially by decreasing $T$ and is decreased extremely rapidly by backing off of the applied field from the critical state. (7) At magnetic fields $Hl{H}_{c1}$ on the initial magnetization curve, no flux creep was observed, but the logarithmic creep rate showed a modest increase above ${H}_{c1}$ and a broad rise as $H$ approached ${H}_{c2}$. The creep process is characterized by a dimension parameter $\mathrm{VX}$ consisting of a flux bundle volume $V$ and pinning length $X$, and by an energy ${U}_{0}$, both of which are supposed to be material-sensitive parameters characteristic of the irreversible processes. These parameters were determined from the experiments. Bundle volumes $V\ensuremath{\approx}{10}^{\ensuremath{-}12}$ ${\mathrm{cm}}^{3}$ and energies ${U}_{0}\ensuremath{\approx}1$ eV were found, indicating that groups of fluxoids must be pinned and must move cooperatively. The results are found compatible with a recent model for flux pinning that includes these cooperative effects.
Formal verification of standards for distance vector routing protocols

We show how to use an interactive theorem prover, HOL, together with a model checker, SPIN, to prove key properties of distance vector routing protocols. We do three case studies: correctness of the RIP standard, a sharp real-time bound on RIP stability, and preservation of loop-freedom in AODV, a distance vector protocol for wireless networks. We develop verification techniques suited to routing protocols generally. These case studies show significant benefits from automated support in reduced verification workload and assistance in finding new insights and gaps for standard specifications.
Trauma group psychotherapy for the adolescent female client.

TOPIC. Therapeutic uses of adolescent trauma group psychotherapy for the treatment of posttraumatic stress disorder. PURPOSE. To demonstrate the role of the psychiatric nurselgroup facilitator to prevent and treat adolescent emotional distress resulting from trauma. SOURCES. Published 1 iterat u re, author S clinical experience. CONCLUSIONS. Adolescent trauma group therapy is useful to deal with emotional, behavioral, maturationalldevelopmental, physiological, cognitive, and sol u t ion-focused issues.
How accurate is angiographic staging of renal carcinoma

Angiographic interpretations were compared with the pathologic findings of 75 patients undergoing nephrectomy for renal carcinoma. Angiography correctly predicted the clinical stage in only 36 per cent of the cases. This failure rate was attributed to the lack of consistent radiologic criteria for determining invasion of the perinephric fat, renal vein, and extension to regional lymph nodes.
Elastic Constants of Solid Ar, Kr, and Xe: A Monte Carlo Study

The elastic constants of classical systems of 108 particles arranged (with periodic boundary conditions) on an fcc lattice and interacting with pairwise-additive forces have been evaluated to an accuracy of about 2% by a Monte Carlo procedure closely related to that used by Hoover and his co-workers. For Ar(80 \ifmmode^\circ\else\textdegree\fi{}K) and Kr(85 and 115 \ifmmode^\circ\else\textdegree\fi{}K) we have used the Bobetic-Barker pair potentials and also included the corrections for the truncated tail of the pair potential, quantum effects, and three-body forces. For Ar(80 \ifmmode^\circ\else\textdegree\fi{}K) and Xe(156 \ifmmode^\circ\else\textdegree\fi{}K) we have carried out a similar calculation for the familiar Lennard-Jones 6:12 potential. Our 6:12 Ar(80 \ifmmode^\circ\else\textdegree\fi{}K) elastic constants agree well with the previous work of Hoover et al. but unfortunately differ only little from the more realistic Bobetic-Barker Ar(80 \ifmmode^\circ\else\textdegree\fi{}K) values. Bulk moduli for both potentials are compatible with the currently available experimental data. Comparison of our Kr results with experimental data indicates a need for refinement of the Bobetic-Barker Kr potential. The Xe(156 \ifmmode^\circ\else\textdegree\fi{}K) results agree very well with the recent Brillouin-scattering work of Gornall and Stoicheff which is to some extent disappointing because the same 6:12 potential is in poor agreement with the low-temperature heat capacity.
Clarification of aqueous corn extracts by tangential flow microfiltration

Abstract The effectiveness of tangential flow microfiltration for the solid/liquid clarification of aqueous corn endosperm and germ extracts was examined using recombinant type I human collagen (rCollagen) and green fluorescent protein (GFP) as model proteins. We identified the effects of transmembrane pressure (TMP), crossflow rate, protein molecular weight, and membrane chemistry on permeate flux, protein rejection, and internal membrane fouling in microfiltration. In dead-end filtrations, both endosperm and germ extracts formed highly compressible cakes that provided the dominant hydraulic resistance. For tangential flow filtration using a ceramic membrane, increasing the crossflow rate had a significant beneficial effect on the permeate flux for all TMPs examined. High fouling of the ceramic membrane occurred during the filtration and this was likely due to the presence of soluble corn starch in the feed. Filtration with a ceramic membrane resulted in low rejection (
Fifteen-to Twenty-Year Study of One Thousand Patients Undergoing Closed Mitral Valvuloplasty

A study is reported of an annual follow-up over a 15- to 20-year period of the survivors of the first 1,000 patients undergoing closed mitral valvuloplasty for mitral stenosis. In addition to a report of the status of the patients at each year of follow-up, a detailed analysis has been made of the factors influencing results of surgery 15 years after operation. The most important factor adversely influencing long-term results is significant mitral valve calcification. This is true regardless of age, sex, preoperative status, concomitant mitral insufficiency or minor degrees of aortic valve disease. A beneficial effect of younger age (below 40 years at surgery) or lack of associated mitral insufficiency is apparent only in Group III patients with noncalcific valves, and in these two subgroups the results were 41 and 37 percent improved, respectively. These figures do not include the large number of patients who have again been improved following a second or even third operation. Late systemic embolization ...
South-seeking magnetotactic bacteria in the Southern Hemisphere

Several species of aquatic bacteria which orient in the Earth's magnetic field and swim along magnetic field lines in a preferred direction (magnetotaxis) have been observed in marine and freshwater sediments of the Northern Hemisphere1,2. Their orientation is due to one or more intracytoplasmic chains of single-domain magnetite particles3. These linearly arranged particles impart a net magnetic dipole moment to the bacterium, parallel to the axis of motility. Northern Hemisphere magnetotactic bacteria with unidirectional motility swim consistently in the direction of the magnetic field, that is, to the geomagnetic North1,2,4. This implies that their magnetic dipole is systematically orientated with the North-seeking pole forward. The magnetic polarity can be reversed by single, magnetic pulses of high field strength (1–2 µs, 300–600 G), and these bacteria then swim along magnetic field lines to the South5. Due to the inclination of the Earth's magnetic field, magnetotactic bacteria which swim to the North in the Northern Hemisphere are directed downward at an angle increasing with latitude. It has been suggested that this downward-directed motion confers a biological advantage by guiding the bacteria, when dislodged, back to the sediments1. On the basis of this hypothesis, magnetotactic bacteria of the Southern Hemisphere would be expected to swim to the South to reach the bottom. We report here several morphological types of magnetotactic bacteria present in sediments of the Southern Hemisphere. These bacteria indeed swim consistently to the South, hence downward along the Earth's inclined magnetic field lines, as hypothesized. As revealed by electron microscopy, they contain internal chains of electron-opaque particles similar to those observed in magnetotactic bacteria from the Northern Hemisphere. Like their Northern Hemisphere counterparts, their magnetic polarity can be permanently reversed and they cannot be demagnetized. We also report on Northern Hemisphere magnetotactic bacteria incubated in Southern Hemisphere magnetic conditions, confirming the biological relevance of downward directed motility.
Maxillary Sinus Augmentation

Attention to the principles of bone grafting, bone healing, and maxillary sinus physiology as well as anatomy is critical to the successful placement of dental implants in the posterior maxilla. The integration of these principles must take into account the restorative dental requirements and the patient's autonomy in guiding implant reconstruction. As in so many clinical disciplines, additional research is needed to provide better guidance for clinicians. Despite some gaps in our knowledge, however, sinus augmentation procedures have proven to be safe and effective and have permitted the placement of implants in sites that would have otherwise been impossible to treat. This article summarizes techniques and technologies related to maxillary sinus augmentation.
Dynamics of gonadotropin-releasing hormone (Gnrh) secretion during the gnrh surge: Insights into the mechanism of gnrh surge induction

Recent studies demonstrate unequivocally that a preovulatory surge of GnRH is secreted into pituitary portal blood during the estrous cycle of the ewe and that this surge is induced by the follicular phase rise in estradiol. These data, obtained at 10-min intervals, suggested the surge results from a continuous elevation of GnRH rather than from a sequence of discrete pulses. This study examines the dynamics of GnRH secretion in more detail to determine if the surge results from strictly episodic release of the decapeptide. Our approach was to monitor GnRH secretion into pituitary portal blood at very frequent intervals during several "windows" of the GnRH surge induced using a physiological model for the estrous cycle. Samples of portal blood were obtained at either 2-min intervals (6 ewes), or 30-sec intervals (12 ewes) at several times during the surge; at other times portal blood was sampled less often to monitor progression of the GnRH surge. All ewes had an unambiguous GnRH surge; amplitude ranged from 100- to 500-fold over pressure levels. Regardless of sampling interval, our results provide no convincing evidence to indicate the enhanced secretion of GnRH is strictly episodic; values remained continuously elevated in portal blood. Our findings are consistent with the hypothesis that the GnRH surge is not composed entirely of discrete synchronous secretory events, and they raise the possibility that one action of estradiol in inducing the GnRH surge may be to switch the pattern of GnRH secretion into portal blood from episodic to continuous.
The inclusion of antisocial behavior in the construct of psychopathy: A review of the research

The psychopathic personality, or the construct of this disorder, has a long and contentious history. Psychopathy has been identified anecdotally for centuries; however, the ability to accurately define this construct continues to challenge researchers and clinicians. Of preliminary concern is the relevance of antisocial behavior to this disorder. Theoretical conceptualizations of psychopathy have changed over the past 65years. Some have stressed the interpersonal and affective deficits of psychopathy [Cleckley, H. (1941). The mask of sanity (1st ed.). St. Louis, MO:C.V. Mosby.], while later conceptualizations have included both personality traits as well as antisocial behavior as criteria of psychopathy [Hare, R. D. (1991/2003). The Hare Psychopathy Checklist–Revised. Toronto, Canada: Multi-Health Systems]. This article will review the literature, particularly the relevance of antisocial behavior to the core personality structure of the psychopath. In doing so, historical theories will be reviewed, followed by later theoretical and empirical research. A great deal of this research has been conducted over the past 15years, since the publication of the Psychopathy Checklist (PCL) and the Psychopathy Checklist-Revised (PCL-R; [Hare, R. D. (1991/2003). The Hare Psychopathy Checklist–Revised. Toronto, Canada: Multi-Health Systems]). The PCL-R has provided the field of psychopathy research with a consistent measurement device, and, therefore will be discussed at length. The limitations of the psychopathy construct will be discussed as well as needed future research and the policy implications of such research.
Single-port laparoscopy: Considerations in children

As the quest to minimize scars from surgery continues, innovative methods of surgery, including single-port surgery, have come to the forefront. Here, we review considerations for surgery in children with particular attention to appendectomy and cholecystectomy. We discuss the future technologies that will aid in single-port surgery and how they apply to the paediatric population.
Experimental determination of the spinel peridotite to garnet peridotite reaction in the system MgO-Al2O3-SiO2 in the range 900 °–1100 °C and Al2O3 isopleths of enstatite in the spinel field

The univariant high-pressure reaction of aluminous enstatite and spinel to pyrope and forsterite in the MgO-Al2O3-SiO2 system has been determined in the temperature range 900 °–1100 °C by hydrothermal reversals in the piston-cylinder apparatus using the low-friction NaCl pressure medium. A mixture of synthetic minerals, including an enstatite with 6 wt% Al2O3, with product and reactant assemblages in nearly equal amounts, was the starting material. The equilibrium pressure of 19.3±0.3 kbar at 1000 ° C and average dP/dT slope of 8.0 bars/ ° C confirm the strong curvature of the equilibrium below 1200 ° C deduced by Obata (1976) from a theoretical study of experimental Al2O3 isopleths of enstatite in the garnet field. His prediction of an absolute minimum pressure near 18 kbar of the garnet peridotite assemblage in the ternary system is undoubtedly correct.
The tortoise shoots back

concept can be the reference of a predicate and that it cannot be the reference of a proper name are, when taken together, inconsistent." (Pp. 60-61.) Thus, the semantical paradox is not Frege's, but Fisk's in his application of a general symbolic formula to Frege's statements of his basic principles. Nevertheless, it is not true, as Fisk holds, that either the paradox is generated (his sentence (9) which contradicts (6) is "sanctioned"), "or it is impossible to raise the general question whether predicates do or do not refer to objects." (P. 59.) As has been indicated the paradox is not generable in Frege's logic and Frege does indeed raise and answer the general question whether predicates do or do not refer to objects. He determined generally that the whole reference of a predicate can never be an object. What Frege cannot do and what Fisk imposes on him is a particular way of asking this question in terms of the use of 'A refers to x.! Frege quite honestly indicates the difficulties of this approach and avoids getting trapped in the use of it.
Multiple Roles for the Ess1 Prolyl Isomerase in the RNA Polymerase II Transcription Cycle

The Ess1 prolyl isomerase in Saccharomyces cerevisiae regulates RNA polymerase II (pol II) by isomerizing peptide bonds within the pol II carboxy-terminal domain (CTD) heptapeptide repeat (YSPTSPS). Ess1 preferentially targets the Ser5-Pro6 bond when Ser5 is phosphorylated. Conformational changes in the CTD induced by Ess1 control the recruitment of essential cofactors to the pol II complex and may facilitate the ordered transition between initiation, elongation, termination, and RNA processing. Here, we show that Ess1 associates with the phospho-Ser5 form of polymerase in vivo, is present along the entire length of coding genes, and is critical for regulating the phosphorylation of Ser7 within the CTD. In addition, Ess1 represses the initiation of cryptic unstable transcripts (CUTs) and is required for efficient termination of mRNA transcription. Analysis using strains lacking nonsense-mediated decay suggests that as many as half of all yeast genes depend on Ess1 for efficient termination. Finally, we show that Ess1 is required for trimethylation of histone H3 lysine 4 (H3K4). Thus, Ess1 has direct effects on RNA polymerase transcription by controlling cofactor binding via conformationally induced changes in the CTD and indirect effects by influencing chromatin modification.
Structural optimization using unconstrained nonlinear goal programming algorithm

Abstract This paper presents a method for solving structural optimization problems using nonlinear goal programming techniques. The developed method removes the difficulty of having to define an objective function and constraints. It also has the capacity of handling rank ordered design objectives or goals. The formulation of the structural optimization problem into a goal programming form is discussed. The resulting optimization problem is solved using Powell's unconstrained conjugate direction search algorithm. To demonstrate the effectiveness of the method, as a design tool, the solutions of some numerical test cases are included.
Histopathology of Salzmann nodular corneal degeneration.

Purpose:To define the histopathology of Salzmann nodular degeneration and suggest potential mechanisms involved in its pathogenesis.Methods:Archived corneal biopsy specimens from 5 patients with Salzmann nodular degeneration were evaluated by chemical and immunohistochemical staining to describe the
Denial of hepatic transplantation on the basis of smoking: is it ethical?

PURPOSE OF REVIEW There is disagreement and inconsistency between liver transplant programs regarding the acceptance or rejection of smokers as candidates for transplantation. This article reviews the outcome data for transplanted smokers, the rate of maintained abstinence from cigarettes by smokers who have quit and the ethics of using tobacco use as a transplant selection criterion. RECENT FINDINGS Consistent with earlier studies, recently published articles continue to demonstrate an increased risk of noncutaneous malignancies, higher rates of graft arterial thrombosis and a higher mortality rate in liver transplant patients who smoke as compared with nonsmokers. There is a significant rate of relapse to smoking after transplantation, and the rates are higher among patients with alcoholic liver disease. Recent studies have shown that 10-16% of patients with biochemical verification of active smoking deny their tobacco use when interviewed for transplant consideration. Although extensively, if not universally, used to exclude transplant candidates, a recent study of marijuana use showed no difference in mortality outcomes as compared with nonusers. SUMMARY With the exception of one recent study, there is substantial literature to support increased morbidity and mortality among posthepatic transplant smokers.
Time dependent difference theory for sound propagation in axisymmetric ducts with plug flow

The time dependent governing acoustic-difference equations and boundary conditions are developed and solved for sound propagation in an axisymmetric (cylindrical) hard wall duct with a plug mean flow and spinning acoustic modes. The analysis begins with a harmonic sound source radiating into a quiescent duct. This explicit iteration method then calculates stepwise in real time to obtain the transient as well as the 'steady' state solutions of the acoustic field. The time dependent finite difference analysis has two advantages over the steady state finite difference and finite element techniques: (1)the elimination of large matrix storage requirements, and (2)shorter solution times under most conditions.
EFFECTS of FILM OVERWRAPPING, VACUUM PACKAGING and VACUUM SKIN PACKAGING ON PSYCHROTROPHIC COUNTS and CHEMICAL CHANGES of ICED CHANNEL CATFISH

Microbial and chemical changes during iced storage of fillets from channel catfish (Ictalurus punctatus) with film overcropping, vacuum packaging, or vacuum skin packaging were determined by psychrotophic plate counts, thiobarbituric acid (TBA), free fatty acid, pH, and ammonia production. Vacuum-packaged fish had significantly lower (p < 0.05) psychrotrophic bacteria counts than overwrapped fish. A significantly higher free fatty acid content was also observed after week two in overwrapped samples. However, vacuum-packaged catfish had the same pH, TBA number, and ammonia production as overwrapped fish on the sampling days throughout three weeks of storage.
A novel method for overlay measurement by scatterometry

The potential of scatterometry has been developed for many years, but it is challenging to accurately and quickly obtain the overlay error from diffraction data. We presented a method to measure the overlay error by choosing an optimal measurement target design for scatterometry. All of the simulations in this study were calculated by rigorous coupled wave analysis. A set of two layer grating model were developed for evaluation of overlay measurement sensitivity at different incident angle, such as theta (0° to 90°) and phi (0° to 180°). We also compared the optical response of zero order and first order diffraction signature. We can use appropriate target design and measured condition to maximize the overlay measurement sensitivity and reduce the noise from lithography printing error. In addition, the diffractive signature imaging microscope (DSIM) is introduced to measure the diffraction signature. This instrument is a full-optical operation system without any mechanical movement, so it has good stabilization.
Recent Decadal Variation in the California Current System

Abstract A study has been made to identify the existence of different decadal climatic regimes before and after the anomalous environmental changes that occurred in 1958. Atmospheric and oceanographic data in the California Current System near San Diego were processed and used for the computation of all oceanic mass transport components. Evidence shows that distinguishable climatic regimes did exist and that in the period of 1957–58 abrupt anomalous variations marked the break between two successive quasi-stable decadal regimes. As the result of overall differences in atmospheric circulation between these two regimes, it is found that there was stronger eastward flow and weaker southward flow in the California Current System near the San Diego area during the present decade than in the previous decade. The direct result of differences in mass transports was to bring more warm and high salinity subtropic water and less cold and low salinity subarctic water into the area of study. These consequences were ev...
Evaluation of a physical length scale for granular materials

Abstract Classical continuum mechanics considers the interaction of microstructural units of the material through stresses and displacements of material points. Therefore, conventional continuum mechanics approaches can not incorporate any intrinsic material length scale. However in reality interaction of grains may include rotations and the corresponding couple stresses as well, and real materials have a number of important length scales (e.g., grains, particles, fibers, etc.). An equation for determining the length scale is proposed. The proposed length scale equations include the effect of plastic deformation (microrotation), the effect of normal stress and contact area. The proposed length scale is implemented into elastic–elastoplastic Cosserat formulation. The effect of length scale on the finite element simulation and yield surface was evaluated by using the proposed length scale equation. The importance of length scale on the constitutive modeling of granular materials is analyzed in numerical simulations.
Acute decline in serum sclerostin in response to PTH infusion in healthy men.

Context: Animal models suggest that the osteoblast-stimulating actions of PTH are mediated by acute suppression of sclerostin, an inhibitor of the anabolic Wnt pathway. The immediate physiological changes in serum sclerostin in response to PTH infusion have not been reported in human studies. Objective: We sought to determine the acute physiological effects of PTH infusion on serum sclerostin and bone turnover markers in healthy adult men. Design, Setting, and Participants: Fifty-three healthy adult men underwent an 18-h iv infusion of human PTH(1-34) at a dose of 0.55 U/kg · h. Outcomes: Serum levels of ionized calcium, sclerostin, and markers of bone formation (osteocalcin and amino-terminal propeptide of type I procollagen) and bone resorption (C-telopeptide and N-telopeptide) were obtained at 0, 6, 12, and 18 h. Results: Serum ionized calcium, C-telopeptide, and N-telopeptide increased, and osteocalcin and amino-terminal propeptide of type I procollagen fell linearly throughout the PTH infusion (P < 0...
Storm time electric fields in the equatorial ionosphere observed near the dusk meridian

[1] We compare the dynamics of plasma drifts (VP) and ionospheric electric fields (EI), measured near the dusk meridian at the magnetic equator by the Defense Meteorological Satellite Program (DMSP) F13 satellite, with those of the dawn-to-dusk component of the interplanetary electric field (IEF) Ey during four large magnetic storms. Presented data indicate that during the main phase of the magnetic storms when the interplanetary magnetic field (IMF) had a southward component, VP had upward and westward components that ranged up to 120 and 210 m s−1. The corresponding eastward and upward components of EI were approximately 5% and 10% of Ey. The persistence of eastward EI for many hours indicates that electric field shielding of the inner magnetosphere is ineffective during prolonged periods of southward IMF. During periods of northward IMF (Ey < 0) ionospheric responses depended on prior history. No ionospheric response is apparent after strong northward IMF turnings preceded by geomagnetic quiet. If they occurred after a long southward interval, EI often had westward and downward components. The polarity of the zonal component of EI remained well correlated with that of Ey for up to 21 h during periods of slowly varying IMF. Phenomena associated with southward IMF periods are consistent with models that allow for prolonged penetration electric field from high latitudes superposed on those of the Sq current system. However, it is not understood why the remarkable correspondence between the polarities of the zonal component of EI and the IEF Ey occurs during northward IMF. In some Ey < 0 periods, the vertical component of EI remained upward. DMSP detections of upward EI (westward VP) during periods of Ey < 0 are not predicted by existing models.