cssi/SciSciGPT-SciSciNet huggingface dataset:
Focal segmental glomerulosclerosis in renal allografts with chronic nephropathy: Implications for graft survival

De novo focal segmental glomerulosclerosis (FSGS) in renal allografts most often is diagnosed in association with chronic allograft nephropathy (CN). In this study, we assessed the clinical and pathological variables that correlate with the presence of de novo FSGS and the implications of FSGS for the survival of grafts with CN. The study population included 293 renal allograft recipients (52 living related donor, 241 cadaveric donor) diagnosed with CN by biopsy more than 6 months after transplantation. Patients with recurrent FSGS or FSGS associated with other glomerulopathies were excluded. FSGS was present in 87 patients with CN (30%). FSGS was diagnosed more commonly in the following groups of patients: young (P = 0.04), black (P = 0.02), and those with elevated serum cholesterol levels (P = 0.002) and/or high-grade proteinuria (P < 0. 0001, all univariate analysis). FSGS was diagnosed later after transplantation than CN without FSGS (P < 0.0001), and FSGS correlated with the presence of arteriolar hyalinosis in the biopsy specimen (P = 0.04). Compared with CN without FSGS, FSGS was associated with significantly worse death-censored graft survival (P = 0.008, univariate Cox). In addition, when we analyzed all patients with CN, graft survival correlated by multivariate analysis with the following parameters: serum creatinine level (P < 0.0001) and proteinuria (P = 0.004) at the time of diagnosis, presence of FSGS (P = 0.03), and degree of interstitial fibrosis and tubular atrophy (CN score; P < 0.0001, Cox). Of interest, the use of lipid-reducing agents was also associated with improved graft survival in patients with CN (P = 0.0002, univariate Cox), although total lipid levels were not significantly less in patients receiving these drugs. In conclusion, de novo FSGS presents late after transplantation and in association with arteriolar hyalinosis, suggesting these lesions may be related to chronic cyclosporine toxicity. In CN, the presence of FSGS and the severity of interstitial fibrosis are negative independent predictors of graft survival. The possible relationship between lipid-reducing agents and graft survival clearly needs to be examined carefully in future studies.
The algebra and geometry of β

Some operations relating to signal detection theory (SDT) analysis are facilitated by expressing β as a function of the z-transformed hit and false alarm rates, z1 and z0, respectively. This expression for the simplest equal-variance SDT model is β = exp[1/2(zo + z1)(zo − z1)].
Least squares collocation solution of differential equations on irregularly shaped domains using orthogonal meshes

The least squares collocation (LESCO) method has been formulated to solve differential equations defined over irregular domains using a more convenient orthogonal computational mesh. The LESCO method is described in detail for second-order boundary value problems and applied to the time-dependent diffusion and advection-diffusion equations defined over two-dimensional irregular domains. Particular attention is given to the proper procedure for applying boundary conditions. Accuracy, convergence, and consistency are examined. For cubic elements with arbitrary location of collocation points, the convergence rate is between 3rd and 4th order. The major advantages of this method are reduced input data requirements, a more robust procedure for forming the equations, positive definite matrices, and flexibility in distrbuting errors.
Synthesis, Characterization, and Crystal Structure of Dicalcium Glutarylbis(phosphonate) Dihydrate: A Covalently Pillared Layer Structure with the Potential for Epitaxial Growth on Hydroxyapatite.

A new bis(acylphosphonate), glutarylbis(phosphonate) (GlBP), was synthesized. Sodium and calcium salts of the GlBP, disodium dihydrogen glutarylbis(phosphonate), NaHO(3)PC(O)(CH(2))(3)C(O)PO(3)HNa, and dicalcium glutarylbis(phosphonate) dihydrate, Ca(2)[O(3)PC(O)(CH(2))(3)C(O)PO(3)].2H(2)O, were prepared and characterized by chemical analyses, thermogravimetry and Fourier transform infrared spectroscopy (FTIR). The crystal structure of the Ca salt was determined by single-crystal X-ray diffraction. The crystals are orthorhombic with a = 10.970(1) A, b = 23.694(2) A, c = 5.580(1) A, space group Pnma, and Z = 4. This study provides the first example of a structure of a calcium complex involving a nongeminal bis(phosphonate). The structure can be described in terms of a covalently pillared layer-type arrangement of neutral Ca-GlBP-Ca units along the b-axis. Each oxygen atom of the phosphonate group is bonded to a different Ca ion, and each Ca in turn is linked to three phosphonate groups. The Ca octahedra and the phosphonate tetrahedra form a two-dimensional polar sheet perpendicular to the b-axis. The chelate bonds involving the keto groups appear to be important links in the stabilization of the structure and, in turn, to the biological activity of bis(acylphosphonates). A near-perfect lattice match, found between the Ca phosphonate layer and the major crystal faces of hydroxyapatite, indicates that epitaxial growth or incorporation of GlBP can occur on the apatitic surface which may be the mode of action in the inhibition of calcification.
Laser tissue soldering in urinary tract reconstruction: First human experience

Abstract Objectives Laser tissue soldering (LTS) in the urinary tract provides an immediate leak-free seal and may avoid complications seen with conventional repair (such as fistula and stricture). We have begun a Phase I clinical trial investigating the use of LTS in performing urologic reconstructive surgery. Methods Ten patients (aged 3 months to 38 years) underwent urologic reconstruction using LTS with a protein solder composed of human albumin (42%) and indocyanine green dye. In each case standard microsuture repair preceded laser-soldered suture line reinforcement. Anastomotic closure time and immediate leak pressure were measured. Postoperatively, all patients were evaluated for evidence of complications, including stricture, fistula formation, or impaired healing. Results Using LTS as an adjunct to suturing added an average of 7.9 ± 3.0 minutes (28%) to the overall mean anastomotic time of 28.3 ± 9.4 minutes. Intraoperative leak pressure measurements for laser-soldered anastomoses (≥94.2 ± 24.2 mm Hg) were significantly higher ( P Conclusions These initial clinical results indicate that LTS is safe, easy to perform, and, contrary to conventional suturing, provides an immediate leak-free closure. Follow-up in these and other patients, as well as those undergoing sutureless and stent-free procedures, will determine whether our method of LTS benefits patients undergoing urologic reconstruction.
Reclaiming fertility awareness methods to inform timed intercourse for HIV serodiscordant couples attempting to conceive

Introduction : Increased life expectancy of HIV-positive individuals during recent years has drawn attention to their quality of life, which includes fulfilment of fertility desires. In particular, heterosexual HIV serodiscordant couples constitute a special group for whom the balance between desired pregnancy and the risk of viral transmission should be carefully considered and optimized. Although advanced assisted reproductive technologies are available, such treatments are expensive and are often unavailable. Moreover, standard viral load testing and antiretroviral therapy may not be accessible due to structural or individual barriers. To reduce the risk of HIV transmission, a lower cost alternative is timed condomless sex combined with other risk-reduction strategies. However, timed condomless sex requires specific knowledge of how to accurately predict the fertile window in a menstrual cycle. The aim of this study was to summarize inexpensive fertility awareness methods (FAMs) that predict the fertile window and may be useful for counselling HIV-positive couples on lower cost options to conceive. Methods : Original English-language research articles were identified by a detailed Medline and Embase search in July 2014. Relevant citations in the included articles were also retrieved. Results and discussion : Calendar method, basal body temperature and cervicovaginal mucus secretions are the most accessible and sensitive FAMs, although poor specificity precludes their independent use in ovulation detection. In contrast, urinary luteinizing hormone testing is highly specific but less sensitive, and more expensive. To maximize the chance of conception per cycle, the likelihood of natural conception needs to be assessed with a basic fertility evaluation of both partners and a combination of FAMs should be offered. Adherence to other risk-reduction strategies should also be advised, and timely referral to reproductive medicine specialists is necessary when sub/infertility is suspected. Conclusions : FAMs provide effective, economical and accessible options for HIV serodiscordant couples to conceive while minimizing unnecessary viral exposure. It is important for health care providers to initiate conversations about fertility desires in HIV-positive couples and to educate identified couples on safer conception strategies. Keywords: HIV; serodiscordant couples; conception; timed intercourse; fertility awareness; fertility evaluation. (Published: 9 January 2015) Citation: Liao C et al. Journal of the International AIDS Society 2015, 18 :19447 http://www.jiasociety.org/index.php/jias/article/view/19447 | http://dx.doi.org/10.7448/IAS.18.1.19447
Seedling growth of three Great Basin wildrye collections at reduced osmotic potential

Abstract Basin wildrye, Leymus cinereus (Scribn. & Merr.) A. Love, syn. Elymus cinereus Scribn. & Merr., is a robust bunchgrass, native to saline and nonsaline semidesert rangelands, in the western U.S.A. Its productive potential and adaptation make it desirable for revegetation of saline soils on rangelands and disturbed areas in temperate semideserts throughout the world. Seedling growth of ‘Magnar’, an improved cultivar of basin wildrye, was compared with that of basin wildrye collected from a saline and from a nonsaline soil in central Nevada to evaluate potential for revegetation. Seedlings were grown hydroponically with nutrient solution osmotic potential reduced by polyethylene glycol (PEG)-6000, NaCl, CaCl2 and equimolar NaCl plus CaCl2. Root growth of all collections was greater in PEG than in CaCl2 or NaCl plus CaCl2. ‘Magnar’ had greater absolute growth than the other collections at all osmotic potentials. The saline soil collection had similar absolute growth but slightly greater relative growth (weight of plants grown at reduced osmotic potentials divided by weight of control plants grown at − 0.06 MPa osmotic potential) than the nonsalines soil collection indicating somewhat greater tolerance to water and salt stress. ‘Magnar’ and the saline soil collection had similar relative growth at reduced osmotic potentials. ‘Magnar’ is recommended when artificially seeding basin wildrye on saline, or nonsaline semidesert soils of temperate rangelands owing to its high germination and absolute growth.
Efficacy of a “Standard” seizure workup in the emergency department

In many institutions it is the "standard of care" to obtain serum chemistries and anticonvulsant levels as part of the emergency department evaluation of seizure patients. To determine the efficacy of such a workup in the ED, 163 seizure patients presenting to an inner-city teaching hospital were studied in a standardized, prospective manner. After the clinical examination all patients had CBC, serum electrolyte, BUN, creatinine, glucose, calcium, magnesium, and if indicated, anticonvulsant drug level determinations performed. Any patient presenting with a first-time seizure (in patients greater than 6 years old), recent head trauma, focal neurologic deficit, or focal seizure activity had cranial computerized tomography (CCT). After obtaining historical and physical examination and before receiving laboratory results, as many as five likely etiologies were listed and assigned probability ratings. After review of the laboratory data (and CCT scan, if obtained), final etiologies again were listed and assigned percentages of likelihood. Significant abnormalities (ie, those that changed diagnosis, management, or disposition) were found in 104 patients; 96 had subtherapeutic anticonvulsant levels, five had abnormal CCT scans, two had hypoglycemia, and one had hyperglycemia as the cause of seizure. The clinical examination successfully predicted those abnormalities in all but two cases (one each of hyperglycemia and subdural hematoma). We contend tha routine serum chemistries in patients presenting to the ED are of extremely low yield, and that the clinical examination can predict accurately the need to obtain these studies. CCT scanning is useful in selected patients, and was found to be abnormal in five of 19 (25%) patients.(ABSTRACT TRUNCATED AT 250 WORDS)
Delivery of G3139 using releasable PEG-linkers: Impact on pharmacokinetic profile and anti-tumor efficacy

Abstract In order to overcome the problems of enzymatic degradation and short plasma half life, which can limit the delivery of antisense oligonucleotides, and the potential immuno-stimulatory effects of CpG motifs, we utilized a polyethylene glycol (PEG) technology that employed various releasable linkers (rPEG). 5′-20 kDa-PEGylation of an anti-Bcl-2 5′-aminoalkyl-oligonucleotide with the same sequence as G3139 (Compound 1 ) did not alter its binding to the heparin-binding protein bFGF, nor the release of cytochrome c from isolated mitochondria treated with the conjugates. However, in 518A2 melanoma cells in vitro , PEGylation resulted in greatly diminished cellular uptake. In striking contrast, PEGylation of 1 resulted in dramatically improved pharmacokinetic profiles in vivo , with a prolonged half-life ( t 1/2 ), increased plasma concentration, and increased area under the plasma concentration–time curve (AUC). In an in vivo melanoma 518A2 xenograft mouse model, treatment with either 5′-20 kDa-PEG- 1 or 1 demonstrated similar tumor growth inhibition. Furthermore, in an in vitro mouse splenocyte culture system, attachment of a PEG moiety to 1 through releasable linkers abolished the immunostimulatory response that was observed for G3139. Our results demonstrate the potential of the in vivo use of PEGylated oligonucleotides, and point out the profound differences between in vitro and in vivo models of oligonucleotide activity.
A porous-jet flow-through electrode.

Abstract An electrochemical flow detector, based on a jet of solution directed at a thin porous carbon electrode, is described, along with its electrochemical characteristics and analytical applications. The electrode has a volume of 19 μl and surface area of 1.26 cm 2 . The detector exhibits better sensitivity and detectability than a wall-jet detector. Dopamine and ferrocyanide were used as test systems to give detection limits at nanomolar concentration levels. Applications indicated include continuous-flow analysis (utilizing stopped-flow voltammetry) and flow-injection analysis.
Event-based modeling and processing of digital media

Capture, processing, and assimilation of digital media-based information such as video, images, or audio requires a unified framework within which signal processing techniques and data modeling and retrieval approaches can act and interact. In this paper we present the rudiments of such a framework based on the notion of "events". This framework serves the dual roles of a conceptual data model as well as a prescriptive model that defines the requirements for appropriate signal processing. Amongst the key advantages of this framework, lies the fact that it fundamentally brings together the traditionally diverse disciplines of databases and (various areas of) digital signal processing. In addition to the conceptual event-based framework, we present a physical implementation of the event model. Our implementation specifically targets the problem of processing, storage, and querying of multimedia information related to indoor group- oriented activities such as meetings. Such multimedia information may comprise of video, image, audio, and text-based data. We use this application context to illustrate many of the practical challenges that are encountered in this area, our solutions to them, and the open problems that require research across databases, computer vision, audio processing, and multimedia.
Aging and word finding reverse vocabulary and cloze tests

Two tasks were used to evaluate age differences in “word-finding difficulty, ”—lexical access and retrieval—for 31 young adults (college students) and 24 healthy, community-dwelling older adults (aged 58 to 86). Comparison of performances on a traditional (forward) and a reverse vocabulary test for the same set of 43 nouns indicated that the aged could define the words as well as or better than the young, but that they had greater difficulty thinking of the word when given the definition. A Cloze task, in which 32 nouns had been deleted from each of four prose passages, required that participants try to guess the deleted words. On this task, the performances of young and old adults were very similar. The only suggestion of greater word-finding difficulty for the aged was that they more often failed to provide any response, although in absolute terms these omission errors were quite rare for both age groups.
Exploring the space of cognitive architectures

Production systems have been proposed as a candidate for the basic architecture of the human information processor. We consider a number of dimensions along which production systems can vary, and we discuss PRISM, a production system formalism designed to aid cognitive modelers in their exploration of the space of architectures. Examples of PRISM settings are presented in the context of particular models. Finally, some heuristics are suggested for efficiently searching the space of possible architectures.
Scanning laser ophthalmoscope design with adaptive optics

A design for a high-resolution scanning instrument is presented for in vivo imaging of the human eye at the cellular scale. This system combines adaptive optics technology with a scanning laser ophthalmoscope (SLO) to image structures with high lateral (~2 μm) resolution. In this system, the ocular wavefront aberrations that reduce the resolution of conventional SLOs are detected by a Hartmann-Shack wavefront sensor, and compensated with two deformable mirrors in a closed-loop for dynamic correction and feedback control. A laser beam is scanned across the retina and the reflected light is captured by a photodiode, yielding a two-dimensional image of the retina at any depth. The quantity of back-scattered light from the retina is small (0.001% of reflection) and requires the elimination of all parasite reflections. As an in vivo measurement, faint cellular reflections must be detected with a low-energy source, a supraluminescent laser diode, and with brief exposures to avoid artifacts from eye movements. The current design attempts to optimize trade-offs between improved wavefront measurement and compensation of the optical aberrations by fractioning the light coming to the wavefront sensor, better sensitivity by increasing the input light energy or the exposure time and the response speed of the system. This instrument design is expected to provide sufficient resolution for visualizing photoreceptors and ganglion cells, and therefore, may be useful in diagnosing and monitoring the progression of retinal pathologies such as glaucoma or aged-related macular degeneration.
Effect of fasting and thermal acclimation on metabolism of juvenile axolotls(Ambystoma mexicanum)

Juvenile axolotls were acclimated to 15°C or 25°C and either fed or fasted at both temperatures, to study the interaction of thermal acclimation and nutritional state on metabolism. Fasting but not thermal acclimation significantly increased oxygen consumption at 15°C. Fasting also increased the specific activities of two oxidative metabolic enzymes — citrate synthase and cytochrome oxidase — but not that of the glycolytic enzyme lactic dehydrogenase. The specific activity of cytochrome oxidase was further stimulated by cold acclimation. Triglycerides and fatty acids were severely depleted in fasted animals, but thermal acclimation had no significant effect on lipid stores. This study illustrates: (1) the differential nature of various metabolic responses to fasting; and (2) the confounding interaction of the nutritional state on thermal acclimation experiments in an ectotherm.
Silica nanoparticle dispersions in homopolymer versus block copolymer

Silica nanoparticles (17 ± 4 nm in diameter) were modified by grafting polystyrene chains to the surfaces using atom transfer radical polymerization (ATRP). The molecular weight of the grafted chains ranged from 8 to 48 kDa. These modified nanoparticles were mixed in solution with poly(styrene) homopolymer (18–120 kDa) and symmetric poly(styrene-b-butadiene) (PS-PB) diblock copolymer (34–465 kDa) and the states of dispersion in the dried composites were characterized by transmission electron microscopy (TEM). In the so-called wet brush limit, when the graft molecular weight equals or exceeds the matrix value, the silica particles form a uniform random dispersion in poly(styrene). Increasing the homopolymer matrix, molecular weight above the graft value results in particle clustering and macroscopic-phase separation. Mixtures of the lamellar forming block copolymer and nanoparticles exhibit a very different trend, with particle clustering at the lower PS-PB molecular weights and dispersion at the highest value. This latter finding is rationalized on the basis of packing constraints associated with lamellar order and the effective particle dimensions, and the degree of solvation at ordering, both of which favor higher molecular weight block copolymers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2284–2299, 2007
A Gene for Lindane + Cyclodiene Resistance in the Red Flour Beetle (Coleoptera: Tenebrionidae)

A field-collected strain of Tribolium castaneum (Herbst) resistant to lindane was genetically purified to make it isogenic with a laboratory-susceptible strain. Cross resistance extended to the cyclodienes dieldrin and oxychlordane but not to methoxychlor, avermectin, malathion, or chlorpyrifos methyl. Back crossing revealed that resistance was monogenic. Linkage analysis and genetic mapping showed that the cyclodiene resistance gene ( lin-H ) is located on the far left end of the third linkage group. Karyotype analysis of a T (Y;3) trans location confirmed that this linkage group is located on the longest autosome. Lin-R is the second insecticide resistance gene to be successfully mapped in T. castaneum .
Getting something for nothing: Estimating service level improvements possible in hospitals

One of the focal points of discussion among firms in the service sector concerns the level of service delivered and its value. In the hospital sector, an important aspect of the level of service relates to the level of quality of care delivered. We undertake an empirical study of 300 U.S. hospitals to evaluate their relative ‘service efficiency’ using the techniques of so-called allocative efficiency. This method estimates the potential improvement in service,, estimates the ideal cost shares of the various resources, and provides the ‘peer group’ members to which the unit is being compared. Utilizing this information, the method proposed for units to improve involves two chief mechanisms. The first is a reallocation of cost shares among the various resource or input types (e.g. no increase in hospital budget). The second involves adopting the management practices used by peer group members. Over all 300 hospitals, a marked improvement potential was found for well over half. Of the poorest performers there appears to be some indication that a larger cost share was needed for face-to-face contact with patients (nursing) and a smaller share for personnel who do not deal with patients directly (lab technicians, non-physician administrators, etc.).
Ziehl-Neelsen's stain for skin sections to show wool and hair follicles.

Ziehl-Neelsen's carbol-fuchsin stain differentiates between the keratin of the medulla and the keratin of the cortex of hair shafts in sections of skin biopsies. Deparaffinized, hydrated sections of Bouin-fixed or formalin-fixed skin of sheep and goats are stained 20-21 hr at about 25° C in carbol-fuchsin. They are rinsed and decolorized in acid alcohol, washed and then counterstained in Harris' haematoxylin. If no additional counterstain is used, the medullary keratin will appear colorless against a dark red acid-fast cortex. In case orange G, as a saturated solution in 95% ethyl alcohol, is applied after the haematoxylin, the medulla will be orange against the red cortex.
A general theory for flooding implementing cuspoids catastrophe

Abstract This paper combines Kelvin-Helmholtz Theory and Catastrophe Theory to develop a general mathematical framework for the flooding phenomenon. The theoretical model proposed in this paper is based on the functional relationship between the gas and liquid flow rates expressed in terms of a modified Kutateladze number that takes into account the effects of entrainment and geometry. A large number of experimental data has been examined against the theoretical model prediction. In most cases, good agreement is obtained by empirically varying only one coefficient.
Thermal stability studies of a globular protein in aqueous poly(ethylene glycol) by 1H NMR

The reversible folding destabilization of hen lysozyme has been confirmed by a melting temperature (Tm) decrease in aqueous poly(ethylene glycol) (PEG). The percent denatured, extracted from the histidine 15 C2H (H15 C2H) native and denatured peak areas from 500-MHz one-dimensional proton nuclear magnetic resonance (1D 1H NMR) spectra in D2O, was analyzed through denaturation temperatures at 0% and 20% (w/w) PEG 1000. The lysozyme (3.5 mM) Tm decreased by 4.2°C and 7.1°C in 20% (w/w) PEG 1000 at pH 3.8 and 3.0, respectively. The Tm decreased with increasing lysozyme concentration. Additionally, the temperature-induced resonance migrations of 17 protons from 8 residues indicate that the native lysozyme structure undergoes temperature-induced conformational changes. The changes were essentially identical in both 0% and 20% (w/w) PEG 1000 at both pH 3.0 and 3.8. This small, local restructuring of the hydrophobic box region may be a manifestation of temperature-dependent solution hydrophobicity, whereas active-site cleft fluctuations may be due to the inherent active-site flexibility. The lysozyme structure in PEG at 35°C was determined to be essentially native from the 1H nuclear Overhauser effect spectroscopy (NOESY) fingerprint regions. Additionally, lysozyme chemical shifts, from 1D spectra, in PEG 200, 300, and 1000 at 35°C and various concentrations were essentially identical, further confirming that the conformation remains native in various PEG solutions. © 1996 John Wiley & Sons, Inc.
The coupling impedance of tape structures

A periodic array of parallel straight tapes is considered. This can propagate a variety of TEM waves, each one corresponding to a different mode of excitation of the tapes. The case in which there is simply a fixed phase-change from one tape to the next is treated in detail. The exact field distribution is determined by using the theory of analytic functions of a complex variable. It is applied to the calculation of the coupling impedances and dispersion curves of tape helices, ladder lines, interdigital lines and meander lines. The calculations show that, with certain provisos, the product of the coupling impedance and the group velocity is the same for all these structures when they have the same tape length, tape width and gap width. The tape length is to be interpreted as the length of one turn in helices and the length of half a turn in meander lines. The provisos are as follows: the phase-change coefficient must be the same in each case; the coupling impedance must be evaluated at the array in helices, averaged over the array in ladder lines and evaluated at the centre lines of the array in interdigital and meander lines; finally, the ladder lines considered must be slightly perturbed easitron structures. Averaging over the array in helices does not alter the coupling impedance. Averaging over the array in interdigital and meander lines reduces the coupling impedance by a factor between 0.5 and 1. In a strongly perturbed easitron structure, the product of the average coupling impedance at the array and the group velocity differs from that in a slightly perturbed easitron structure by a factor for which an approximate formula is given. The use of tape structures in travelling-wave tubes for the millimetre wavebands is discussed briefly.
Rho GTPases in animal cell cytokinesis: an occupation by the one percent.

Rho GTPases are molecular switches that elicit distinct effects on the actomyosin cytoskeleton to accurately promote cytokinesis. Although they represent less than 1% of the human genome, Rho GTPases exert disproportionate control over cell division. Crucial to this master regulatory role is their localized occupation of specific domains of the cell to ensure the assembly of a contractile ring at the proper time and place. RhoA occupies the division plane and is the central positive Rho family regulator of cytokinesis. Rac1 is a negative regulator of cytokinesis and is inactivated within the division plane while active Rac1 occupies the cell poles. Cdc42 regulation during cytokinesis is less studied, but thus far a clear role has only been shown during polar body emission. Here we review what is known about the function of Rho family GTPases during cell division, as well as their upstream regulators and known downstream cytokinetic effectors. © 2012 Wiley Periodicals, Inc
L-arginine attenuates trauma-hemorrhage-induced liver injury.

Objectives: Liver injury is common after trauma-hemorrhage for which the underlying mechanism is not clear. Although administration of the essential amino acid L-arginine has been reported to restore the depressed cardiovascular functions and cell-mediated immune responses after trauma-hemorrhage, it remains unknown whether L-arginine protects against liver injury under those conditions. Design: A prospective, controlled animal study. Setting: A university research laboratory. Subjects: Male Sprague-Dawley rats. Interventions: Rats underwent sham operation or laparotomy and were bled to and maintained at a mean arterial blood pressure of 40 mm Hg until 40% of the maximum shed blood volume was returned in the form of lactated Ringer's solution. Hemorrhaged rats were then resuscitated with lactated Ringer's solution, four times the maximum shed blood volume over 1 hr. During resuscitation, animals received either 300 mg/kg of L-arginine or saline (vehicle) intravenously. At 3 and 5 hrs after resuscitation, rats were killed, blood was obtained, and the liver was fixed for histology (hematoxylin & eosin staining). Plasma glutathione S-transferase (a marker of liver damage), L-arginine, citrulline, and ornithine concentrations were assessed. Measurements and Main Results: The increased concentrations of plasma glutathione S-transferase observed in vehicle-treated hemorrhage animals were normalized with L-arginine treatment at 5 hrs after resuscitation. Moreover, the histology indicated that L-arginine prevented liver edema and neutrophil infiltration after trauma-hemorrhage. Plasma L-arginine and citrulline were increased in L-arginine-treated rats. Conclusions: Because citrulline is a by-product of nitric oxide generation by nitric oxide synthase from L-arginine, this amino acid may be a useful adjunct for preventing hepatic injury after trauma-hemorrhage via endothelial derived nitric oxide production.
Formation of supernumerary structures by the embryonic chick wing depends on the position and orientation of a graft in a host limb bud

Abstract The relationship between the position transplanted in a host limb bud, the orientation of a graft in a host limb bud, and the extra limb structures formed was studied by juxtaposing normally nonadjacent embryonic chick wing bud tissue. In one series of transplantation operations, two different wedges (ectoderm and mesoderm) of stage 21 right donor posterior wing bud tissue were transplanted to the middle of a host stage 20 to 22 right wing bud such that the dorsal-ventral polarity of the graft and host were the same or reversed. The results of these transplantation operations show that the formation of supernumerary limb structures depends on the position of origin of the donor tissue, the anterior-posterior position transplanted in a host limb bud, and the orientation of the graft in the host limb bud. In a second series of transplantation operations, the relationship between the proximodistal position where posterior donor tissue is transplanted in an anterior host site and the extra structures formed was studied. A wedge of posterior stage 21 right wing bud tissue was transplanted to an anterior proximal or anterior distal site of a stage 22 to 24 host right wing bud. The results of these transplantation operations show that when the donor tissue is transplanted to an anterior proximal position in a host wing bud, then limbs with only a duplicated humerus result, whereas, when transplanted to an anterior distal position, then limbs with a duplicated forearm element and extra digits result.
Interventricular heterogeneity as a substrate for arrhythmogenesis of decoupled mitochondria during ischemia in the whole heart

Myocardial ischemia results in metabolic changes, which collapse the mitochondrial network, that increase the vulnerability of the heart to ventricular fibrillation (VF). It has been demonstrated a...
Reversible pulmonary trunk banding with a balloon catheter: assessment of rapid pulmonary ventricular hypertrophy.

Abstract Objective: We sought to assess the rapid hypertrophy of the right ventricle of young goats submitted to progressive pressure load by a balloon catheter. Methods: The hearts of 6 young goats were assessed by means of echocardiography and cell morphology during and after right ventricular hypertrophy had been produced by a balloon catheter. Myocardial samples of the right ventricular outflow tract were harvested for microscopic studies. The external diameter of longitudinally sectioned myocytes was measured at the nucleus level. The volume density of mitochondria was also determined. A balloon catheter was then placed through the right ventricular outflow tract in the pulmonary trunk and progressively inflated every 2 days. Postoperative serial echocardiography was performed at intervals of 1 to 2 days. The animals were killed after 2 to 3 weeks of right ventricular training for morphologic analysis. Results: Under optical microscopy, there was a 20.5% increase in the mean diameter of the myocyte of the trained right ventricle. However, under electron microscopy, there was no significant change in the mean volume density of mitochondria from the trained right ventricle. Serial echocardiography showed equalization of the ventricular thickness over a short interval of 6 to 10 days of progressive balloon inflation. Conclusions: The balloon catheter permits the manipulation of the pressure load over the right ventricle, causing rapid hypertrophy in a 6- to 10-day period. This study suggests that nonsurgical preparation of the "pulmonary ventricle" in patients with transposition of great arteries with intact ventricular septum beyond the neonatal period could probably be accomplished within a very few days. (J Thorac Cardiovasc Surg 2000;120:66-72)
A 30 kg Capacity High Precision Load Cell Mass Comparator

Described here are simple means to fabricate a 30 kg mass comparator based on an ordinary direct reading load cell. The mass comparator performs with a precision of 1 ppm.
Angina Pectoris at Rest with Preservation of Exercise Capacity Prinzmetal's Variant Angina

Twenty patients with Prinzmetal's variant of angina are described and the literature on the subject is reviewed. This syndrome is characterized by anginal attacks at rest with S-T segment elevation, while exercise capacity is well preserved. Coronary arteriography usually demonstrates significant, focal, obstuctive disease of the major coronary artery predicted from the distribution of S-T elevation seen in the ECG during attacks. Occasionally the coronary disease is minimal or absent. The cause of attacks is believed to be transient, spastic occlusion of a major coronary artery, which was actually observed during surgery in one case. Because of this unusual pathophysiology, these patients may not make ideal candidates for isolated saphenous vein bypass surgery. Other diagnostic, therapeutic, and prognostic implications of this interesting anginal syndrome are discussed.
The pragmatics of negation in Brazilian Portuguese

Sentential negation in Brazilian Portuguese (BP) has been of considerable theoretical interest in syntax, semantics, and typology, because of the fact that there exist three different formal possibilities for expressing negation in this language. However, the conditions under which each form can and cannot be employed have not been clearly specified in prior research, being characterized instead as due to intuitive notions like emphasis or poorly-defined applications of concepts such as presupposition. In this paper, it is shown that these prior analyses are inadequate since they cannot predict the (non-) occurrence of the different negatives in BP. Using both naturally-occurring and constructed data, it is demonstrated that there are important pragmatic differences between the three ways of negating a sentence in BP. These differences are crucially determined by information structure, specifically the discourse status (old/new) of the proposition being denied. Such a clear interrelationship between choice of negative form and information structure represents an important contribution to the study of negation as well as to the field of pragmatics.
Hydrodeoxygenation of lignin model compounds over a copper chromite catalyst

Abstract The hydrodeoxygenation of benzyl alcohol, phenol, anisole, o-cresol, catechol, guaiacol, and vanillyl alcohol were carried out from 150 to 275 °C at 50 bar H 2 with a CuCr 2 O 4 ·CuO catalyst in a decalin solvent. The hydroxymethyl group of benzyl alcohol was found to be highly reactive towards hydrogenolysis to form toluene. Demethoxylation of anisole to form benzene was found to be the primary reaction pathway in contrast to demethylation and transalkylation reactions, which are more prevalent for conventional hydrotreating catalysts. The hydroxyl group of phenol strongly activated the aromatic ring towards hydrogenation forming cyclohexanol which was subsequently dehydrated and hydrogenated to form cyclohexane. Reaction networks of increasing complexity were devised for the major functional groups and integrated to describe the most complex molecule studied, vanillyl alcohol.
The reaction of O(1D) with CH4

The room-temperature photolysis of N2O (10–100 torr) at 2139 A to produce O(1D) has been studied in the presence of CH4 (10–891 torr). The reactions of O(1D) with CH4 were found to be The method of chemical difference was used to measure the rate constant ratio k4/(k2 + k3), where reactions (2) and (3) are The CH3 radicals produced in reaction (4) react with the O2 and NO produced in reactions (2) and (3). Thus, near the endpoint of the internal titration, ϕ{C2H6} gives an accurate measure of k4/(k2 + k3). For the translationally energetic O(1D) atoms produced in the photolysis, k4/(k2 + k3) = 2.28 ± 0.20. However, if He is added to remove the excess translational energy, then k4/(k2 + k3) drops to 1.35 ± 0.3.
The taxonomic significance of the fatty acid content of seeds of Linum

About sixty taxa in the genusLinum are arranged systematically and are compared using data published earlier for the fatty acid content of their seeds. Plants of sect.Linum, of sect.Dasylinum, and Old World species of sect.Linastrum generally have higher percentages of linolenic acid and lower percentages of linoleic acid; plants of sect.Syllinum, of sect.Cathartolinum, and New World species of sect.Linastrum have the reverse tendencies. The segregation ofL. stelleroides from other species of sect.Linum and the maintenance ofL. tenuifolium in a section separate from other tested species are supported.
Comparison of Immunohistochemistry with Reverse Transcription-PCR for the Detection of Micrometastatic Prostate Cancer in Lymph Nodes

The objective is to compare the performance of immunohistochemistry (IHC) with that of reverse transcription (RT)-PCR for detecting clinically significant micrometastases in histopathologically normal archival pelvic lymph nodes (PLN) removed at radical prostatectomy from men with locally advanced nonmetastatic prostate cancer. We stained 1864 fixed, paraffin-embedded PLNs from 199 pT 3 N 0 M 0 prostate cancer patients for prostate-specific antigen (PSA) and cytokeratin. We also assessed human glandular kallikrein (hK2) expression in a subset of 164 patients. In addition, all PLN specimens were assayed for hK2 mRNA using a previously described RT-PCR assay. PSA and cytokeratin were expressed in the same 13 of 199 (7%) cases; hK2 was expressed in 3 of 164 (2%) cases. PSA/cytokeratin and hK2 expression were associated with cancer involvement of seminal vesicles, higher Gleason sum, and a positive RT-PCR-hK2 assay result. In standard postoperative multivariable models, IHC-PSA/IHC-Cytokeratin or IHC-hK2 was associated with prostate cancer progression, development of distant metastases, and prostate cancer-specific survival. However, when RT-PCR-hK2 assay result was added to the models, it was the sole predictor of clinical outcomes. Although IHC-PSA/IHC-Cytokeratin and IHC-hK2 were more specific for identifying patients who would suffer biochemical progression and develop metastases and who would ultimately die of prostate cancer, RT-PCR-hK2 was more sensitive and accurate. Although IHC for PSA, cytokeratin, and hK2 appear to be more specific methods for detecting biologically and clinically significant prostate cancer micrometastases in histopathologically normal PLN, RT-PCR-hK2 appears to be a more sensitive method that maintained a reasonable specificity. In pT 3 N 0 patients, a positive RT-PCR-hK2 assay result when performed on PLN was the strongest predictor of clinical outcomes after radical prostatectomy.
Inhomogeneity and binding energy of biexcitons in quantum wells using 2D Fourier-transform spectroscopy

Two-dimensional Fourier-transform spectroscopy shows a strong variation in the biexciton binding energy across the inhomogeneous absorption width. This effect is observed for both co- and cross-linearly polarized excitation, where the latter suppresses many-body interactions.
Batch-fabricated thin-film magnetic recording heads

Fabrication of thin-film recording heads with 30-μm wide gaps in 25-μm thick Permalloy have been reported previously. Formation of narrow gaps by chemical etching was limited by undercutting. This paper describes a process for fabricating thin-film recording heads with gaps 2 μm wide in Permalloy film which is 2.5 μm thick. The process makes use of electroplating, photoetching, and electron beam technologies. The narrow gaps with vertical walls are made possible by the use of electron sensitive resist, electron beam exposure of 2-μm wide strips, and electroplating of 2.5-μm thick films of Permalloy on each side of the narrow strip of the electron sensitive resist.
Use of strontium isotopes to constrain the timing and mode of dolomitization of upper Cenozoic sediments in a core from San Salvador, Bahamas

The /sup 87///sup 86/Sr ratios and the activity ratios of /sup 234/U//sup 238/U and /sup 230/Th//sup 238/U have been measured in dolomites from a 168-m-deep core taken on the island of San Salvador, Bahamas. These data suggest two periods of dolomitization. The first episode dolomitized Miocene age sediments during the latest Miocene, and the second dolomitized the Pliocene portion of the core and was still active as recently as 150 ka. The late timing of the second episode argues against penecontemporaneous models of dolomitization for the Pliocene sediments. Instead, dolomitization is favored either as a result of mixing-zone development during the large Pleistocene sea-level changes or by movement of seawater through the platform.
Organismus und Umwelt

Lange wurde die wissenschaftliche Biologie von der Annahme bestimmt, Organismen seien bemerkenswert gut an die Welt, in der sie leben, angepasst. Tatsachlich wurde die aussergewohnliche Ubereinstimmung zwischen den Fahigkeiten von Lebewesen und den Anforderungen durch ihre Lebensumstande als Beweis fur die Macht und Gute des Heiligen Schopfers angesehen. Wie anders konnten wir auch erklaren, dass Tiere, die im Wasser leben, Flossen zum Schwimmen und Kiemen zum Atmen haben, wahrend Tiere, die durch die Luft fliegen, Flugel und Lungen besitzen. Zusammen mit der Frage nach der Ursache fur Artenvielfalt fuhrte diese Beobachtung uber die Anpassung von Organismen an deren Lebensbedingungen Darwin dazu, eine umfassende Evolutionstheorie zu begrunden. Er stellte fest, dass der Prozess, der zu immer besser angepassten Lebewesen fuhrte, der gleiche war, der auch die Artenvielfalt hervorbrachte. Die Individuen, deren Anatomie, Physiologie und Verhalten am besten an die Umweltbedingungen angepasst waren, hatten die groste Chance, das Fortpflanzungsalter zu erreichen und die meisten Nachkommen zu produzieren. Wenn solche Charakteristika erblich sind, dann werden sie in der nachsten Generation mit hoherer Frequenz vertreten sein, was schlieslich dazu fuhrt, dass die gesamte Art aus den am besten angepassten Typen besteht.
Origin and rapid diversification of a tropical moss.

Molecular sequences rarely evolve at a constant rate. Yet, even in instances where a clock can be assumed or approximated for a particular set of sequences, fossils or clear patterns of vicariance are rarely available to calibrate the clock. Thus, obtaining absolute timing for diversification of natural lineages can prove difficult. Unfortunately, without absolute time we cannot develop a complete understanding of important evolutionary processes, including adaptive radiations and key innovations. In the present study, the coding sequence of the nuclear gene, glyceraldehyde 3-phosphate dehydrogenase (gpd), extracted from the paleotropical moss, Mitthyridium, was found to exhibit clocklike behavior and used to reconstruct the history of 80 distinct molecular lineages that cover the full geographic range of Mitthyridium. Two separate clades endemic to two geographically distinct oceanic archipelagos were revealed by this phylogenetic analysis. This allowed the use of island age (as derived from potassium-argon dating) as a maximum age of origin of each monophyletic group, providing two independent time anchors for the clock found in gpd, the final piece needed to study absolute time. Based on results from both maximum age calibrations, which separately yielded highly consistent estimates, the ancestor of this moss group arose approximately 8 million years ago, and then diversified at the rapid rate of 0.56 ± 0.004 new lineages per million years. Such a rate is on par with the highest diversification rates reported in the literature including rapidly radiating insular groups like the Hawaiian silversword alliance, a classic example of an adaptive radiation. Using independent sources of data, it was found that neither the age nor diversification estimates were affected by the use of molecular lineages rather than species as the operational taxonomic units. Identifying the cause for this rapid diversification requires further testing, but it appears to be related to a general shift in reproductive strategy from sexual to asexual, which may be a key innovation for this young group.