cssi/SciSciGPT-SciSciNet huggingface dataset:
Filter penetration measurements using a condensation nuclei counter and an aerosol photometer

Abstract We conducted both theoretical and experimental comparisons of two instruments, a condensation nuclei counter and an aerosol light-scattering photometer, to determine how they measured the penetration of high-efficiency particulate air (HEPA) filters. In some experiments we simulated leaks around the test filter to ascertain how such leaks affect the two instruments' penetration measurements. Results of all of our experiments indicate that differences in the measurements vary widely from no difference to a factor of 10. These variations are related to certain functions that depend on particle size: the response function of the photometer, the filter penetration, and the distribution of the test aerosol. The use of appropriate aerosol diagnostics enabled us to measure these functions and compare numerical calculations to experimental results. Agreement between theory and experiment is good. Consequently, given these function, the penetration values obtained in one instrument can be related to the other's. In general, test aerosols with larger standard deviations produce greater discrepancies between the two instruments' measurements. For sufficiently large leaks, the penetrations reported by the two instruments approach the same value, regardless of the distribution of the test aerosol.
Insulin Receptors and Insulin Resistance in Human Pregnancy: Evidence for a Postreceptor Defect in Insulin Action*

Pregnancy is accompanied, in its later stages, by physiological resistance to the action of insulin. We studied the potential contribution of altered insulin receptors to this phenomenon in 12 healthy pregnant women during their third trimester. For comparison, we studied the same women again several weeks postpartum. We also used a group of randomly chosen nonpregnant subjects as a control population. Women in this control group were studied during the luteal phase of the menstrual cycle. Plasma insulin and insulin to glucose ratios were significantly higher in the pregnant women. Insulin binding to peripheral blood monocytes was higher in pregnancy than postpartum in the majority of women, and as a group, the pregnant subjects showed significantly higher insulin binding than the nongravid subjects. This appeared to be due to a greater number of receptor sites per cell. We found no correlation between plasma insulin and insulin binding in pregnancy. We conclude that the insulin resistance of pregnancy is...
Amyloid fibril formation by a domain of rat cell adhesion molecule.

Amyloid fibrils are protein aggregates implicated in several amyloidotic diseases. Cellular membranes with local decrease in pH and dielectric constant are associated with the amyloid formation. In this study, domain 1 of cell adhesion molecule CD2 (CD2-1) is used for studying amyloid fibril formation in a water/trifluoroethanol (TFE) mixture. CD2-1 is an all β-sheet protein similar in topology to the amyloidogenic light chain variable domain, which deposits as amyloid in light chain amyloidosis at acidic pH. When incubated at pH 2.0 in the presence of 18% TFE, CD2-1 initiates the process to assemble into amyloid fibrils. It has been shown that TFE induces CD2-1 conformational change with a chemical transition (Cm) of 18% (v/v). ANS (1-anilinonapthalene-8-sulfonic acid) binding was used to show that the hydrophobic surface becomes exposed under these solvent conditions. Our studies indicate that partial formation of a non-native conformation and the exposure of the hydrophobic interior could be the origins of oligomerization and fibril formation of CD2-1.
Overexpression of α-synuclein decreased viability and enhanced sensitivity to prostaglandin E2, hydrogen peroxide, and a nitric oxide donor in differentiated neuroblastoma cells

Increased accumulation of alpha-synuclein is associated with certain neurodegenerative diseases including Parkinson's disease (PD) and Alzheimer's disease (AD). One mechanism of alpha-synuclein-induced toxicity involves increased oxidative stress. It was unknown whether neurons overexpressing alpha-synuclein would exhibit increased sensitivity to hydrogen peroxide (H(2)O(2)) or 3-morpholinosydnonimine (SIN-1; a nitrous oxide donor). To study this, we developed a murine neuroblastoma (NB) cell line that overexpresses wild-type human alpha-synuclein (NBP2-PN54) under the control of the cytomegalovirus (CMV) promoter using a retroviral vector. Human alpha-synuclein mRNA and protein were readily detectable in NBP2-PN54 cells. Results showed that differentiated NBP2-PN54 cells exhibited decreased viability in comparison to differentiated vector (NBP2-PN1) and parent (NBP2) control cells. These cells also exhibited increased sensitivity to PGE(2), H(2)O(2) and SIN-1. Because of involvement of proteasome inhibition in neurodegeneration, we also investigated whether treatment of differentiated NBP2-PN54 cells with PGE(2), H(2)O(2) or SIN-1 inhibits proteasome activity. Results showed that H(2)O(2) and SIN-1 inhibited proteasome activity, but PGE(2) did not. These results suggest that overexpression of alpha-synuclein not only participates directly in degeneration of neurons, but it also increases the vulnerability of neurons to other potential neurotoxins.
“Closed-Vein” Technique for Primary Sutureless Repair of Anomalous Pulmonary Venous Connection

Deep hypothermic circulatory arrest or low-flow bypass are commonly used in primary repair of total anomalous pulmonary venous connection, or individual veins may be dissected to allow clamp or snare application, in order to provide a bloodless field for anastomosis by the direct or sutureless marsupialization technique. In the described technical modification, the marsupialization of the opened atrium to the posterior pericardium is completed before opening the pulmonary venous confluence, allowing bloodless exposure during full-flow normothermic bypass. In addition, vein branch dissection is avoided.
Dual Mechanisms of DNA Damage by MoCH3(η3-allyl)(CO)2(phen) Complexes

DNA damage by MoCH3(η3-allyl)(CO)2(phen) complexes has been shown to occur by two mechanisms: by backbone cleavage via the abstraction of H1‘ and/or H5‘ from the deoxyribose moiety and by base mod...
Association of AKI with Mortality and Complications in Hospitalized Patients with Cirrhosis

Acute kidney injury (AKI) is a common and devastating complication in patients with cirrhosis. However, the definitions of AKI employed in studies involving patients with cirrhosis have not been standardized, lack sensitivity, and are often limited to narrow clinical settings. We conducted a multicenter, prospective observational cohort study of patients with cirrhosis and AKI, drawn from multiple hospital wards, utilizing the modern acute kidney injury network (AKIN) definition and assessed the association between AKI severity and progression with in-hospital mortality. Of the 192 patients who were enrolled and included in the study, 85 (44%) progressed to a higher AKIN stage after initially fulfilling AKI criteria. Patients achieved a peak severity of AKIN stage 1, 26%, stage 2, 24%, and stage 3, 49%. The incidence of mortality, general medical events (bacteremia, pneumonia, urinary tract infection), and cirrhosis-specific complications (ascites, encephalopathy, spontaneous bacterial peritonitis) increased with severity of AKI. Progression was significantly more common and peak AKI stage higher in nonsurvivors than survivors (P < 0.0001). After adjusting for baseline renal function, demographics, and critical hospital- and cirrhosis-associated variables, progression of AKI was independently associated with mortality (adjusted odds ratio = 3.8, 95% confidence interval 1.3-11.1). Conclusion: AKI, as defined by AKIN criteria, in patients with cirrhosis is frequently progressive and severe and is independently associated with mortality in a stage-dependent fashion. Methods for earlier diagnosis of AKI and its progression may result in improved outcomes by facilitating targeted and timely treatment of AKI. (HEPATOLOGY 2013)
In vitro susceptibility of cephalothin-resistant enterobacteriaceae andPseudomonas aeruginosa to a one-oxa cephalosporin (LY 127935 or moxalactam), amikacin, and selected cephalosporins

LY 127935 (moxalactam), a new 1-oxa cephalosporin, was evaluated in vitro in agar dilution testing against 177 different clinical isolates of cephalothin-resistant Enterobacteriaceae andPseudomonas aeruginosa in parallel with amikacin, cephalothin, cefoxitin, and cefamandole. Ninety percent of the isolates were also gentamicin-resistant by disk testing. LY 127935 showed a very high degree of activity against cephalothin-resistant organisms but amikacin was more active in vitro, particularly againstP. aeruginosa. Cefoxitin and cefamandole were consistently less active than either LY 127935 or amikacin.
Clinical trial of a novel filler material for soft tissue augmentation of the face containing synthetic calcium hydroxylapatite microspheres.

BACKGROUND The ideal injectable filler should yield great, long-lasting results, be biocompatible, reliable, safe, easy to use, and inexpensive. Radiesse (Bioform Inc., Franksville, WI) is a synthetic calcium hydroxylaptic filler that has all of the above qualities. OBJECTIVE To evaluate the effectiveness of Radiese as an injectable filler. METHODS Eighty-two patients who underwent facial soft tissue augmentation using Radiese from April 2003 to 2004 were enrolled in this study. Pre-filled sterile syringes were used to inject the material into the soft tissues of the face. At the 3 month and six month visits, the physicians and the patients were asked to evaluate the result. RESULTS Eighty-two patients were injected with Radiesse. The most common area of injection was the melolabial folds. All patients were evaluated during the 3 month follow up visit. There was an overwhelmingly positive response to the look and feel of the implant, averaging 4.6 on a grading scale from 1 to 5, for the patients as well as the injecting physicians. Similar responses were found at the 6 month follow up visit. CONCLUSION Preliminary data indicate that Radiesse is easy to use and effective with little or no associated morbidity.
A model for reaching control

In this paper we propose that reaches are made to target postures which are selected by evaluating stored postures. Target postures are chosen by taking a weighted average of the stored postures, where the weights assigned to the stored postures depend on their effectiveness for the task. Movements from starting postures to target postures are achieved by reducing the distance, in joint space, between the two. The form of the movement depends on drive (assumed to decrease as less distance remains) and inertia. The model predicts the Power Law of learning, compensation for immobility of joints, changes in limb contributions depending on movement speed, asymmetric bell-shaped velocity profiles, velocity-amplitude relations, Fitts' Law, and position-dependent variations in hand-path curvature. Planned extensions of the model may broaden its application-for example, to handwriting.
Effect of intellectual lifestyle and Alzheimer's disease biomarkers on rate of cognitive decline: Mayo Clinic Study of Aging

dementia when compared to the individuals with no formal education (N1⁄490). After adjustment for sociodemographics and neuropathologic features including neuritic plaques, neurofibrillary tangles, lacunar infarctions, small vessel disease, and Lewy bodies, 1-4 years of education education had an OR1⁄40.54, 95%CI 0.28-1.02; p1⁄40.06;>4 years had an OR1⁄40.38, 95%CI 0.17-0.88; p1⁄40.02. Higher brain weight was also associated to lower frequency of dementia in adjusted analysis (OR1⁄4 0.64, 95% CI: 0.49-0.85, p1⁄40.002). The interaction between education and brain weight was not related do dementia (p1⁄40.37). Conclusions: Higher education and brain weight are associated with lower frequency of dementia. Education and brain weight may represent different domains of neural reserve.
Modelling cross-sectional profitability and capital intensity using panel corrected significance tests

Employing seemingly unrelated regression (SUR) models with panel corrected standard errors (PCSE) this research augments and extends Fama and French's (2000) ‘first stage’ model of expected cross-sectional profitability. Capital intensity, defined as the ratio of depreciation plus interest expense to total assets was found to be significantly inversely related to profitability. In addition, specific market sector and country fixed-effects proved significant in models that simultaneously corrected for cross-sectional heteroscedasticity and cross-equation residual correlation. Both of these corrections addressed the potential bias from least squares standard errors or ‘inference problem’ noted in the previous work by Fama and French. Unrestricted and restricted SUR cross-sectional models with PCSE are used to compute t-statistics based on Fama–MacBeth, Litzenberger–Ramaswamy and standard panel methodologies. The former two methods provided significant results compared to those using the Fama–MacBeth approach.
The role of arousal in the creation and control of the halo effect in attitude models

Within the framework of attitude theory, this study investigates the conditions under which the halo effect can be (a) created where none normally exists and (b) reduced or eliminated where it does occur. A laboratory experiment was conducted to induce physiological arousal as a mechanism for influencing halo. Using a spreading activation model of semantic memory to frame predictions, it was hypothesized and found that arousal produced a halo effect for positive beliefs, tended to reduce halo for negative beliefs, and eliminated halo (marginally) for all beliefs treated as an aggregate. The context for the study was attitudes toward blood donation. A total of 220 people participated in a fully randomized two-group posttest-only design with multiple covariates and measurement error taken into account explicitly. Theoretical and applied implications are discussed. © 1996 John Wiley & Sons, Inc.
Impact of Flt-3 ligand on donor-derived antigen presenting cells and alloimmune reactivity in heart graft recipients given adjuvant donor bone marrow.

The influence of the haematopoietic growth factor Flt-3 ligand (FL) on the incidence and function of donor major histocompatibility complex (MHC) class II+ cells in the lymphoid tissues of non-cytoablated recipients of heart allografts and donor bone marrow (BM) cells was investigated. C3H (H2k) mice received a nonvascularized B10 (H2b) heart allograft in the dorsal ear pinna, followed by an i.v. influsion of 50 × 106 donor BM cells. They were given FL (10 μg/day i.p., ×7 days), tacrolimus (2mg/kg/day i.p., ×13 days) or both agents immediately following heart transplantation (HTx) and were killed 10 or 21 days later. Their BM cells were propagated in vitro in granulocyte macrophage colony stimulating factor (GM-CSF) and IL-4 for 5 days to promote the growth of dendritic cells (DC). Donor DC were identified by immunocytochemical staining. Spleens were harvested, and donor (IAb+) cells enumerated by immunohistochemical analysis. Donor MHC class II DNA was detected in spleens and cultured BM-derived cells by reverse transcriptase-polymerase chain reaction (RT-PCR). A striking increase in donor MHC class II+ cells was noted in both the spleen and BM of the BM + tacrolimus-treated group compared to either the BM alone, or BM + FL-treated groups. Addition of FL treatment to BM + tacrolimus led to a further increase in donor cells in spleen (three-fold at 10 days, and two-fold at 21 days) The increase in donor cells at 10 days was almost 140-fold compared to that with donor BM alone. PCR analysis at this time revealed enhanced donor DNA in the BM + FL + tacrolimus group compared to that in the BM + tacrolimus group. FL treatment augmented mixed leucocyte reactions (MLR) and cytotoxic T lymphocyte (CTL) activity of host spleen cell against donor alloantigens. These effects were reversed by tacrolimus administration. Histopathology of heart grafts from tacrolimus-treated animals at 10 and 21 days showed absence or substantial reduction in cellular infiltration, and the preservation of viable myocardium. By contrast, in untreated mice, or animals given BM or BM + FL alone, there was marked cellular infiltration, and features of accelerated rejection. Donor-derived DC could be propagated in vitro from the BM of heart transplant recipients given donor BM, especially from mice that also received tacrolimus ± FL. At day 21, donor-derived cells could only be propagated from the BM + FL + tacrolimus-treated group. These findings show that numbers of donor antigen presenting cells (APC) or their progenitors can be markedly
Missing Pieces, Repetitive Practices: Child Sexual Exploitation and Institutional Settings

The sexual abuse and exploitation of children is a serious problem. Adult sexual predators often use strategies known as grooming to entice their victims. These include targeting particularly vulnerable youth, gift giving, and systematically engaging in desensitizing sexual behaviors. Less commonly discussed is the notion of institutional grooming, the practice of strategically placing themselves in positions of public trust where they have access to children yet appear beyond reproach. Once situated, they can abuse children for decades without deterrence in spite of the fact that individuals around them may be aware–or partially aware–of their behavior. This article examines three cases, one involving a priest, another a football coach, and the third a pediatrician and considers the institutional practices and cultures that permit (or potentially permit) abuse and exploitation to flourish. Among other things it finds: confidentiality mandates and other codes of silence and secrecy impede information shar...
Use of Image-based Mnemonic Techniques to Enhance the Memorability of User-generated Passwords

Participants in this study were assigned to one of three different password generation groups: image-based mnemonic, text-based mnemonic, or proactive password checking restrictions alone; and asked to generate and later recall passwords for five separate fictitious online accounts. Password accuracy and recall time were measured following both a short-term (10-minute) and long-term (1-week) delay. Results indicated that passwords were more quickly generated and accurately recalled when they were generated using the image-based mnemonic technique or proactive password restrictions alone, as opposed to the text-based mnemonic technique. Furthermore, use of the image-based mnemonic technique resulted in the generation of passwords that were more resistant to forgetting. Implications and future research considerations are discussed.
A New Histone at the Centromere

The centromere is a classic system to study epigenetic specification, and most research has focused on a specialized histone variant, CENP-A, that is required for kinetochore assembly. Now Nishino et al. reveal a new level of complexity for centromeric chromatin, by showing that the kinetochore complex CENP-T-W-S-X shares structural and functional properties with canonical histones.
Adaptive Dynamic Programming for Feedback Control

Summary form only given. Living organisms learn by acting on their environment, observing the resulting reward stimulus, and adjusting their actions accordingly to improve the reward. This action-based or reinforcement learning can capture notions of optimal behavior occurring in natural systems. We describe mathematical formulations for reinforcement learning and a practical implementation method known as adaptive dynamic programming. These give us insight into the design of controllers for man-made engineered systems that both learn and exhibit optimal behavior. Relations are shown between ADP and adaptive control.
Existence of solutions to some initial value, two-point and multi-point boundary value problems with discontinuous nonlinearities

A variety of initial and boundary value problems in applied mathematics have nonlinear, discontinuous forcing terms. Existence theorems for problems of this sort are established for initial value, two-point, and multi-point boundary value problems for ordinary differential equations. Applications to steady-state heat conduction problems are given
Female contact modulates male aggression via a sexually dimorphic GABAergic circuit in Drosophila

Intraspecific male-male aggression, which is important for sexual selection, is regulated by environment, experience and internal states through largely undefined molecular and cellular mechanisms. To understand the basic neural pathway underlying the modulation of this innate behavior, we established a behavioral assay in Drosophila melanogaster and investigated the relationship between sexual experience and aggression. In the presence of mating partners, adult male flies exhibited elevated levels of aggression, which was largely suppressed by prior exposure to females via a sexually dimorphic neural mechanism. The suppression involved the ability of male flies to detect females by contact chemosensation through the pheromone-sensing ion channel ppk29 and was mediated by male-specific GABAergic neurons acting on the GABAA receptor RDL in target cells. Silencing or activating this circuit led to dis-inhibition or elimination of sex-related aggression, respectively. We propose that the GABAergic inhibition represents a critical cellular mechanism that enables prior experience to modulate aggression.
Large modular structures for adaptive beamforming and the Gram-Schmidt preprocessor

An alternate derivation of the modular structure for linearly constrained minimum variance beamforming proposed in Liu and Van Veen (1991) is presented using a vector space approach. This approach eliminates the tedious algebra employed in that paper and establishes the relationship between the modular structure and the Gram-Schmidt preprocessor (Mozingo and Miller, 1980). The modular structure is obtained using a factorization of the orthogonal projection operator in Hilbert space. The Gram-Schmidt preprocessor is a special case of the general modular decomposition. It is also shown that these structures offer computational efficiencies when multiple beamformers are implemented simultaneously. >
Two Conceptions of Sustainability

Mathis Wackernagel and William Rees describe the ‘ecological footprint’ (i.e. the ecological capacity, measured in hectares of biologically productive land, needed to supply a given person’s consumption of natural resources and absorb their waste) as a conception of environmental sustainability, and have accumulated significant data to measure the footprints of nations, cities and even individual persons. Although the authors refrain from explicitly drawing normative inferences from their measurements, such implications lie not far beneath the surface of their work. Besides providing an empirical tool for assessing efforts to improve environmental performance, the footprint implies a normative ideal of global resource egalitarianism, once the conception is examined through the lens of contemporary political theory. In this article, I trace out the normative implications of ecological footprinting in comparison and contrast with those of carrying capacity, an alternative conception of sustainability which the footprint ought (or so I shall argue) to replace. The concept of environmental sustainability identifies a state of affairs and invests it with normative import: in reference to the essential life-supporting capacities of the environment (providing clean air, water, food and a stable climate), sustainability results from acts or policies which allow for the human use of ecological services in perpetuity without their diminution (the ideal with which the concept is associated), avoiding those unsustainable ones which are incompatible with that aim. As a contested concept, however, sustainability offers competing normative premises and evaluative standards with its various formulations, identifying different root causes of environmental problems and prescribing different remedies to those problems with rival accounts of the concept’s meaning and measurement. Given the importance of promoting sustainability in practice, a sound conceptual framework must provide the means by which progress toward the ideal can be tracked (distinguishing sustainable actions and policies from unsustainable ones) while grounding the ideal itself in a defensible normative foundation. Together, these criteria offer the critical standards by which alternative conceptions of sustainability may be compared; the latter is necessary for identifying the desirable state of affairs to be promoted, and the former for the operational means to realizing that ideal. Both of these criteria are essential, for the failure of either prevents the concept from being used in the service of promoting a genuinely sustainable world, either because we cannot know what such a world looks like or because we will not know how to get there from here. The normative implications of competing conceptions of sustainability typically go unnoticed by those relying upon the evaluative standards that they entail, yet
Satisfactory visualization rates of standard cardiac views at 18 to 22 weeks' gestation using spatiotemporal image correlation.

Objective. The purpose of this study was to determine the frequency with which 3 standard screening views of the fetal heart (4-chamber, left ventricular outflow tract [LVOT], and right ventricular outflow tract [RVOT]) can be obtained satisfactorily with the spatiotemporal image correlation (STIC) technique. Methods. A prospective study of 111 patients undergoing anatomic surveys at 18 to 22 weeks was performed. Two ultrasound machines with fetal cardiac settings were used. The best volume set that could be obtained from each patient during a 45-minute examination was graded by 2 sonologists with regard to whether the 4-chamber, LVOT, and RVOT images were satisfactory for screening. Results. All 3 views were judged satisfactory for screening in most patients: 1 sonologist graded the views as satisfactory in 70% of the patients, whereas the other found the views to be satisfactory in 83%. The position of the placenta did not alter the probability of achieving a satisfactory view, but a fetus in the spine anterior position was associated with a significantly lower probability that the views were regarded as satisfactory for screening (odds ratio, 0.28; 95% confidence interval, 0.09―0.70; P < .05). Conclusions. This study suggests that STIC may assist with screening for cardiac anomalies at 18 to 22 weeks' gestation.
Kin structure, ecology and the evolution of social organization in shrimp: a comparative analysis

Eusocial societies present a Darwinian paradox, yet they have evolved independently in insects, mole-rats and symbiotic shrimp. Historically, eusociality has been thought to arise as a response to ecological challenges, mediated by kin selection, but the role of kin selection has recently been questioned. Here we use phylogenetically independent contrasts to test the association of eusociality with ecological performance and genetic structure (via life history) among 20 species of sponge-dwelling shrimp (Synalpheus) in Belize. Consistent with hypotheses that cooperative groups enjoy an advantage in challenging habitats, we show that eusocial species are more abundant, occupy more sponges and have broader host ranges than nonsocial sister species, and that these patterns are robust to correction for the generally smaller body sizes of eusocial species. In contrast, body size explains less or no variation after accounting for sociality. Despite strong ecological pressures on most sponge-dwellers, however, eusociality arose only in species with non-dispersing larvae, which form family groups subject to kin selection. Thus, superior ability to hold valuable resources may favour eusociality in shrimp but close genetic relatedness is nevertheless key to its origin, as in other eusocial animals.
Prioritizing perioperative quality improvement in orthopaedic surgery.

Background: Surgical quality improvement has received increasing attention in recent years, but it is not clear where orthopaedic surgeons should focus their efforts for the greatest impact on perioperative safety and quality. We sought to guide these efforts by prioritizing orthopaedic procedures according to those that generate the greatest number of adverse events. Methods: We used data from the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) to identify all patients who had undergone an orthopaedic surgical procedure between 2005 and 2007 (n = 7970). Patients were assigned to forty-four unique procedure groups on the basis of the Current Procedural Terminology (CPT) codes. We first assessed the relative contribution of each procedure group to the overall number of adverse events in the first thirty postoperative days, and we followed that with a description of their relative contribution to an excess length of stay in the hospital. Results: Ten procedures accounted for 70% of the adverse events and 65% of the excess hospital days. Hip fracture repair accounted for the greatest share of adverse events, followed by total knee arthroplasty, total hip arthroplasty, revision total hip arthroplasty, knee arthroscopy, laminectomy, lumbar/thoracic arthrodesis, and femoral fracture repair. No other procedure group accounted for >2% of the adverse events. Conclusions: Only a few procedures account for the vast majority of adverse events in the first thirty days following orthopaedic surgery. Concentrating quality-improvement efforts on these procedures may be an effective way for surgeons and other stakeholders to improve perioperative care and reduce costs in orthopaedic surgery. Level of Evidence: Prognostic Level II. See Instructions to Authors for a complete description of levels of evidence.
A Method for Measuring Cerebral Hemispheric Blood Flow and Metabolism

A new method for measuring cerebral hemispheric blood flow together with metabolism using an injection of a 5 ml bolus of hydrogen-saturated saline into each internal carotid artery is described. This method was extensively evaluated in the monkey prior to being used in man. Under fluoroscopic control, a catheter was inserted into each cerebral transverse sinus via the basilic veins. Hemispheric blood flow was calculated from the clearance curves of hydrogen from the transverse sinus following injection using a formula based upon the Stewart-Hamilton principle. Hemispheric metabolic index for oxygen was estimated using a new formula by assuming that the distribution of hydrogen into each transverse sinus following injection of the bolus indicates the distribution of the blood from each hemisphere into each transverse sinus. This method has certain advantages over the conventional method for measuring cerebral blood flow, since the actual geometry of the brain in which the blood flow measured is known and simultaneous estimations of hemispheric metabolism are possible. Abnormalities of hemispheric blood flow and metabolism have been measured in 30 patients suffering from various neurological disorders including occlusion of one internal carotid artery. The new formula for estimating hemispheric metabolism is applicable to radioisotopic and other indicator injection methods in which blood is sampled from the cerebral transverse sinuses or internal jugular veins. It was also shown that the transverse sinus distribution of blood derived from each cerebral hemisphere varies from one individual to another.
Gentamicin and Tobramycin Pharmacokinetics in Pediatric Bone Marrow Transplant Patients

OBJECTIVE:To describe the pharmacokinetic parameters of gentamicin and tobramycin in pediatric bone marrow transplant patients.DESIGN:Retrospective medical record review.Setting: Pediatric bone marrow transplant unit in a university teaching hospital.MAIN OUTCOME MEASURES:Pharmacokinetic parameters (apparent volume of distribution [Vd] in L/kg, half-life [t1/2] in h, elimination rate constant [ke] in h−1, clearance [Cl] in mL/min/1.73 m2 and mL/min/kg) calculated from serum concentrations.PATIENTS:Thirty-three patients aged 15 years or less who underwent bone marrow transplant and received gentamicin or tobramycin.RESULTS:Mean pharmacokinetic parameters were Vd 0.32 ± 0.07 L/kg, t1/2 2.32 ± 0.65 h, Cl 1.71 ± 0.53 mL/min/kg, and Cl 86.2 ± 24.5 mL/min/1.73 m2. Factors such as disease state, type of marrow graft, gender, or exposure to cyclosporine had no significant effect on pharmacokinetic parameters. Linear regression indicated a weak relationship between serum creatinine (SCr) and Cl in mL/min/kg (r = 0...
Gramicidin A Induces Metabolic Dysfunction and Energy Depletion leading to Cell Death in Renal Cell Carcinoma Cells

Ionophores are lipid soluble organic molecules that disrupt cellular transmembrane potential by rendering biological membranes permeable to specific ions. They include mobile-carriers which complex with metal cations and channel-formers that insert into the membrane to form hydrophilic pores. Although mobile-carriers possess anticancer properties, investigations on channel-formers are limited. Here, we utilized the channel-forming ionophore gramicidin A (GA) to study its effects upon the growth and survival of renal cell carcinoma (RCC) cells. RCC is a histologically heterogeneous malignancy that is highly resistant to conventional treatments. We found that GA reduced the in vitro viability of several RCC cell lines at sub-micromolar concentrations (all IC50 < 1.0μM). GA exhibited similar toxicity in RCC cells regardless of histological subtype or the expression of either the von Hippel-Lindau (VHL) tumor suppressor gene or its downstream target hypoxia-inducible factor (HIF) -1α. GA decreased cell viability equal to or greater than the mobile-carrier monensin depending on the cell line. Mechanistic examination revealed that GA blocks ATP generation by inhibiting oxidative phosphorylation and glycolysis leading to cellular energy depletion and non-apoptotic cell death. Finally, GA effectively reduced the growth of RCC tumor xenografts in vivo. These results demonstrate a novel application of GA as a potential therapeutic agent for renal cell carcinoma therapy.
The Influence of the Avatar on Online Perceptions of Anthropomorphism, Androgyny, Credibility, Homophily, and Attraction

It has become increasingly common for Web sites and computer media to provide computer generated visual images, called avatars, to represent users and bots during online interactions. In this study, participants (N = 255) evaluated a series of avatars in a static context in terms of their androgyny, anthropomorphism, credibility, homophily, attraction, and the likelihood they would choose them during an interaction. The responses to the images were consistent with what would be predicted by uncertainty reduction theory. The results show that the masculinity or femininity (lack of androgyny) of an avatar, as well as anthropomorphism, significantly influence perceptions of avatars. Further, more anthropomorphic avatars were perceived to be more attractive and credible, and people were more likely to choose to be represented by them. Participants reported masculine avatars as less attractive than feminine avatars, and most people reported a preference for human avatars that matched their gender. Practical and theoretical implications of these results for users, designers, and researchers of avatars are discussed.
2. reasons, generalizations, empathy, and narratives: The epistemic structure of action explanation

It has become something of a consensus among philosophers of history that historians, in contrast to natural scientists, explain in a narrative fashion. Unfortunately, philosophers of history have not said much about how it is that narratives have explanatory power. They do, however, maintain that a narrative's explanatory power is sui generis and independent of our empathetic or reenactive capacities and of our knowledge of law-like generalizations. In this article I will show that this consensus is mistaken at least in respect to explanatory strategies used to account for rational agency using the "folk-psychological" framework of intentions, beliefs, desires, and the like. Philosophers distinguish insufficiently among different aspects and different types of information needed for a historian to persuasively account for an agent's behavior in particular circumstances. If one keeps these aspects apart it will become apparent exactly how one should understand the epistemic contribution of empathy, generalizations, and narrative for the explanation of action.
A Common Origin for Organics in Meteorites and Comets: Was It Interstellar?

The insoluble organic material preserved in primitive chondritic meteorites shares many similarities with the refractory organic material in interplanetary dust particles and comets, suggesting that there is a genetic link between the organic matter in objects that formed between ~3 AU and ~30 AU from the Sun. These similarities include large D and 15N enrichments in bulk and even more extreme enrichments in isotopic hotspots. The enrichments attest to formation in very cold environments, either in the outer Solar System or the protosolar molecular cloud. There are many properties of this organic material that are consistent with an interstellar origin, but a Solar System origin cannot be ruled out. Similar organic material is presumably an important component of most protoplanetary disks, and heating or sputtering of this material would be a source of PAHs in disks. The soluble organic matter was more heavily effected by processes on the chondritic parent bodies than the insoluble material. Amino acids, for instance, probably formed by reaction of ketones and aldehydes with NH3 and HCN. The accretion of the relatively volatile NH3 and HCN, presumably in ices, strengthens the chondrite-comet connection. However, unlike most comets the water in chondrites, when it was accreted, had D/H ratios that were similar to or depleted relative to Earth.
Biventricular Pacemaker Optimization Guided by Comprehensive Echocardiography—Preliminary Observations Regarding the Effects on Systolic and Diastolic Ventricular Function and Third Heart Sound

Background Doppler echocardiography of mitral inflow or aortic outflow or both has been validated and advocated to guide biventricular (Biv) pacemaker optimization. A comprehensive and tailored Doppler echocardiographic evaluation may be required in patients with heart failure to assist with Biv pacemaker optimization. The third heart sound (S 3 ), an acoustic cardiographic parameter, has been demonstrated to be a highly specific finding for hemodynamic evaluation in patients with heart failure. The aims of this study were to evaluate the use of comprehensive Doppler echocardiography as a guide during Biv pacemaker optimization in patients after cardiac resynchronization therapy and to evaluate the feasibility of S 3 intensity to be a cost-efficient parameter for Biv pacemaker optimization compared with Doppler echocardiography. Methods Comprehensive Doppler echocardiographic evaluations were performed during Biv pacemaker optimization in 44 patients referred for pacemaker optimization (mean age, 71 ± 12 years; mean left ventricular ejection fraction, 34 ± 11%). Blinded assessment of S 3 intensity was performed simultaneously using acoustic cardiography. The correlation and improvement in cardiac hemodynamics were analyzed between the methods. Results Echocardiographically guided optimization resulted in significant improvements in the left ventricular outflow velocity-time integral (15.92 ± 4.77 to 18.51 ± 5.19 cm, P P P P 3 intensity from 4.81 ± 1.84 at baseline to 3.96 ± 1.22 after optimization ( P P 3 intensity > 5.0. The correlation between echocardiographic and acoustic cardiographic S 3 intensity for optimal atrioventricular delay was 0.86 ( P P 3 intensity in 56%, and optimal interventricular delay was identical in 75% of patients. Pacemakers were permanently programmed on the basis of echocardiographic evaluation. In 35 patients available for follow up, the mean New York Heart Association class reduced from 2.55 ± 0.81 to 1.77 ± 0.90 ( P P = .08) at 2.5 ± 2.1 months. Conclusion Comprehensive echocardiographically guided Biv pacemaker optimization produces significant improvement in Doppler echocardiographic hemodynamics, a reduction in S 3 intensity, and an improvement in functional class in patients after cardiac resynchronization therapy.
A simple and effective electroporation apparatus.

Description d'un appareil d'electroporation facilement realisable, qui est efficace avec des cellules d'E. coli ou avec du materiel plus complexe et plus couteux. Il permet l'utilisation d'un voltage bas (400 volts), et est tres facile a nettoyer ou a steriliser
Sporulation and rna2 lower ribosomal protein mRNA levels by different mechanisms in Saccharomyces cerevisiae.

Abstract In Saccharomyces cerevisiae, the levels of ribosomal protein mRNAs are regulated coordinately. Vegetative strains carrying the temperature-sensitive rna2 mutation exhibit a dramatic decrease in the levels of most ribosomal protein mRNAs at the restrictive temperature. Similarly, in wild-type cells induced to sporulate by nitrogen starvation, there is a fivefold reduction in the relative synthesis rate of ribosomal proteins. Using Northern gel analysis and cloned ribosomal protein genes, we compared the way in which ribosomal protein mRNA is affected under these two conditions. In vegetative rna2 cells, incubation at 34 degrees C led to the disappearance of ribosomal protein mRNAs and the accumulation of higher-molecular-weight precursor RNAs. A different phenotype was observed during sporulation. Although sporulating conditions led to a significant reduction in the relative abundance of ribosomal protein mRNA, there was no detectable accumulation of precursor RNAs even in rna2/rna2 diploids at 34 degrees C. A suppressor of rna2 and of other rna mutations, SRN1, at least partially relieved the block in the splicing of the ribosomal protein 51 intron in vegetative rna2 cells but did not detectably affect the level of ribosomal protein mRNA in sporulating cells. We concluded that the rna2 mutation and sporulation conditions affected ribosomal protein mRNA metabolism in two quite different ways. In vegetative cells the mutant rna2 effected a block which occurred primarily in post-transcriptional processing, whereas in sporulating cells the ribosomal protein mRNA levels were decreased by some other mechanism, presumably a change in the relative rate of transcription or mRNA turnover. Furthermore, the data suggest that the mutation rna2 has no additional effect on ribosomal protein mRNA metabolism in sporulating cells.
Manipulating objects with internal degrees of freedom: Evidence for model-based control

There is substantial evidence that humans possess an accurate and adaptable internal model of the dynamics of their arm that is utilized by the nervous system for controlling arm movements. However, it is not known if such model-based strategies are used for controlling dynamical systems outside the body. The need to predict events in the external world is not restricted to the execution of reaching movements or to the handling of rigid tools. Model-based control may also be critical for performing functional tasks with non-rigid objects such as stabilizing a cup of coffee. The present study investigated the strategies used by humans to control simple mass-spring objects. Subjects made straight line reaching movements to a target while interacting with a robotic manipulandum that simulated the dynamics of a one-dimensional mass on a spring. After learning, neither hand nor object kinematics returned to those of free reaching, suggesting that this task was not learned as a perturbation of free reaching. Although there are control strategies (such as slowing the movement of the hand) that would require little or no knowledge of object dynamics, subjects did not adopt these strategies. Instead, they tailored their motor commands to the particular object being manipulated. When object parameters were unexpectedly altered in a way that required no changes in kinematics to successfully complete the task, subjects nonetheless exhibited substantial kinematic deviations. These deviations were consistent with those predicted by a model of the arm-plus-object system driven by a low-impedance controller that incorporated an explicit inverse model of arm-plus-object dynamics. The observed behavior could not be reproduced by a controller that relied on modulating hand impedance alone with no inverse model. These results were therefore consistent with the hypothesis that subjects learn to control the kinematics of manipulated objects by forming an internal model that specified the forces to be exerted by the hand on the object to induce the desired motion of that object.
Extraction and characterization of triglycerides from coffeeweed and switchgrass seeds as potential feedstocks for biodiesel production

Background Although switchgrass has been developed as a biofuel feedstock and its potential for bioethanol and bio-oil from fast pyrolysis reported in the literature, the use of the seeds of switchgrass as a source of triglycerides for biodiesel production has not been reported. Similarly, the potential for extracting triglycerides from coffeeweed (an invasive plant of no current economic value) needs to be investigated to ascertain its potential economic use for biodiesel production. Results The results show that coffeeweed and switchgrass seeds contain known triglycerides which are 983 and 1000 g kg(-1) respectively of the fatty acids found in edible vegetable oils such as sunflower, corn and soybean oils. In addition, the triglyceride yields of 53-67 g kg(-1) of the seed samples are in the range of commercial oil-producing seeds such as corn (42 g kg(-1) ). Conclusion The results also indicate that the two non-edible oils could be used as substitutes for edible oil for biodiesel production. In addition, the use of seeds of switchgrass for non-edible oil production (as a feedstock for the production of biodiesel) further increases the total biofuel yield when switchgrass is cultivated for use as energy feedstock for pyrolysis oil and biodiesel production. © 2016 Society of Chemical Industry.
Co-Design of Strain-Actuated Solar Arrays for Precision Pointing and Jitter Reduction

Many important spacecraft operations require precision pointing such as space astronomy and high-rate communications. Traditionally, reaction wheels have been used for this purpose but they have been considered unreliable for many missions. This work presents the use strain-actuated solar arrays (SASA) for precision pointing and jitter reduction. Piezoelectric actuators can achieve higher precision and bandwidth than reaction wheels, and they can also provide quiet operation for sensitive instruments. The representation of the array dynamics in the studies presented here is based on Euler-Bernoulli beam theory for high-fidelity simulations. This work also presents a methodology for the combined design of distributed structural geometry for the arrays and distributed control system design. The array geometry design allows for a distributed thickness profile, and the control design determines the distributed moment on the array. Fundamental limits on slew magnitude are found using pseudo-rigid body dynamic model (PRBDM) theory. A parametric study based on a representative spacecraft model demonstrates the validity of the proposed approach and illustrates optimal design trends.