cssi/SciSciGPT-SciSciNet huggingface dataset:
Defect-free asymmetric hollow fiber membranes from Torlon®, a polyamide–imide polymer, for high-pressure CO2 separations

Abstract Torlon ® , a polyamide–imide polymer, was used for high-pressure CO 2 separations, as it can form inter- and intra-chain hydrogen bonding that may provide stability against plasticization. Asymmetric hollow fiber membranes with a defect-free selective skin were successfully formed from Torlon ® using a dry–wet spinning process. Dope and spinning parameters were optimized to obtain these fibers, which had CO 2 /CH 4 selectivity of 44 and O 2 /N 2 selectivity of 7.7. These selectivities are about 85% of the intrinsic (dense film) value of 52 for CO 2 /CH 4 and 90% of the intrinsic value of 8.3 for O 2 /N 2 , respectively. Based on analyses presented, the reduced selectivities are attributed to substructure resistance rather than actual skin layer defects. Macrovoids, which compromise the strength of the fiber, were reduced by increasing the polymer concentration. The resulting fiber could withstand up to 2000 psi of N 2 , and a CO 2 permeation study indicates that this fiber can perform selective separations under supercritical conditions of 1100 psi of CO 2 at 35 °C.
Superconductivity in new A-15 niobium alloys

A number of previously unreported A-15 Nb alloys have been studied, using samples prepared by dual target sputtering.T c was measured resistively and structure determined by x-ray diffraction. Samples were “chemically” analyzed by anodization. New alloys include A-15 Nb3Si and pseudobinary derivatives, as well as some derivatives of “Nb3P.”T c and the A-15 lattice parameter were surveyed for these, and for previously studied alloys related to Nb3Al, Nb3Ga, and Nb3Ge. The “chemical” variation ofT c was slight, except near pure Nb3Si and for alloys based upon “Nb3P,” where the samples show considerable disorder. Maxima inT c occur for the alloys Nb3Al0.7Ge0.3 and Nb3Al0.5Ga0.5. The first is well known; trends measured here indicate that the second may be equally high. It is proposed that the dominant factor forT c in this group of alloys is the state of order achieved in the samples. No evidence was seen to associate enhancedT c with A-15 phase boundaries.
Gold Nanorods Carrying Paclitaxel for Photothermal-Chemotherapy of Cancer

Nanotechnology-based photothermal therapy has emerged as a promising treatment for cancer during the past decade. However, heterogeneous laser heating and limited light penetration can lead to incomplete tumor cell eradication. Here, we developed a method to overcome these limitations by combining chemotherapy with photothermal therapy using paclitaxel-loaded gold nanorods. Paclitaxel was loaded to gold nanorods with high density (2.0 × 104 paclitaxel per gold nanorod) via nonspecific adsorption, followed by stabilization with poly(ethylene glycol) linked with 11-mercaptoundecanoic acid. Paclitaxel was entrapped in the hydrophobic pocket of the polymeric monolayer on the surface of gold nanorods, which allows direct cellular delivery of the hydrophobic drugs via the lipophilic plasma membrane. Highly efficient drug release was demonstrated in a cell membrane mimicking two-phase solution. Combined photothermal therapy and chemotherapy with the paclitaxel-loaded gold nanorods was shown to be highly effectiv...
THE ACTION OF STREPTONIGRIN ON BACTERIAL DNA METABOLISM AND ON INDUCTION OF PHAGE PRODUCTION IN LYSOGENIC BACTERIA.

Abstract Net DNA synthesis is preferentially inhibited in Salmonella typhimurium by treatment with the antibiotic streptonigrin. As with other agents that affect DNA synthesis, short exposures to streptonigrin result in excellent induction of phage production in inducible lysogenic bacteria. Moreover, these cells produce good yields of active phage when maintained in the presence of the inhibitor until lysis occurs. The characteristics of a cell line which shows a high degree of resistance to the antibiotic are described.
Resident Training in Laboratory Hematology

The authors of this article formulate a strategy to guide residents and faculty in laboratory hematology. The authors build upon the recommendations of the Academy of Clinical Laboratory Physicians and Scientists (ACLPS) published earlier as well as draw from their own experiences, in discussing principles that should be considered when implementing a program that effectively trains residents to be competent pathologists in the various settings that they may encounter once they complete training.
Histopathologic features of composite ganglioneuroblastoma. Immunohistochemical distinction of the stromal component is related to prognosis

Histopathologic features of 18 cases of composite ganglioneuroblastoma (CGNB) were studied with immunohistochemical staining techniques using antibodies against S-100 protein (S-100), ferritin (FER), and leukocytic common antigen (LCA). Cases of CGNB were divided on the basis of the morphologic features of neuroblastic elements into three prognostic subgroups: "Type A Intermixed," having individual microscopic nests of neuroblasts (N = 4, 100% survival); "Type B Intermixed," having microscopic aggregates of multiple neuroblastic nests (N = 6, 67% survival); and "Nodular," having grossly visible nodule(s) of neuroblastic proliferation (N = 8, 0% survival). Survival rates are significantly different for the prognostic subgroups (P less than 0.025). Each prognostic subgroup demonstrated an immunohistochemically distinct pattern of stromal cell composition in the neuroblastic elements: Type A Intermixed had numerous S-100 cells and no FER cells, Type B Intermixed contained many S-100 cells and a moderate number of FER cells, and Nodular had few S-100 cells with many FER cells. The S-100 and FER scores, determined by counting the positive cells through a line sampling method, differed significantly between these prognostic subgroups. Lymphocytic aggregations in tumor tissue evaluated by volumetric assessment with LCA staining, on the other hand, showed no contribution in predicting the outcome of the patients. There was also an inverse relationship between S-100 and FER score, suggesting a relationship between the relative predominance of these stromal cell types, tumor histopathologic features, and the biologic behavior of CGNB.
Effects of plant litter on foraging and nesting behavior of prairie rodents

Interspecific differences in seed use and location of nest sites of Peromyscus leucopus, P. maniculatus, Reithrodontomys megalotis , and Microtus ochrogaster were found among experimental patches of habitat that differed only in amount of plant litter. P. leucopus and P. maniculatus foraged selectively in patches with sparse litter and used nest boxes in these patches more than expected. R. megalotis and M. ochrogaster foraged selectively and nested in patches with moderate litter; both nested more in litter than in nest boxes. All species consumed more seeds in patches with moderate litter on bright than dark nights. P. leucopus consumed fewer seeds and P. maniculatus tended to reduce consumption from dark to bright nights; however, R. megalotis and M. ochrogaster consumed similar amounts of seeds under both light conditions. P. leucopus and P. maniculatus forage in open habitats and may perceive changes in light intensity more readily than either R. megalotis or M. ochrogaster that forage in structurally complex habitats. Interspecific differences in activity between dark and bright nights may be related to the ability of each species to detect changes in risk of predation related to variation in light intensity.
Adapting MapReduce for HPC environments

MapReduce is increasingly gaining popularity as a programming model for use in large-scale distributed processing. The model is most widely used when implemented using the Hadoop Distributed File System (HDFS). The use of the HDFS, however, precludes the direct applicability of the model to HPC environments, which use high performance distributed file systems. In such distributed environments, the MapReduce model can rarely make use of full resources, as local disks may not be available for data placement on all the nodes. This work proposes a MapReduce implementation and design choices directly suitable for such HPC environments.
Delivery of large biopharmaceuticals from cardiovascular stents: A review

This review focuses on new and emerging large-molecule bioactive agents delivered from stent surfaces in drug-eluting stents (DESs) to inhibit vascular restenosis in the context of interventional cardiology. New therapeutic agents representing proteins, nucleic acids (small interfering RNAs and large DNA plasmids), viral delivery vectors, and even engineered cell therapies require specific delivery designs distinct from traditional smaller-molecule approaches on DESs. While small molecules are currently the clinical standard for coronary stenting, extension of the DESs to other lesion types, peripheral vasculature, and nonvasculature therapies will seek to deliver an increasingly sophisticated armada of drug types. This review describes many of the larger-molecule and biopharmaceutical approaches reported recently for stent-based delivery with the challenges associated with formulating and delivering these drug classes compared to the current small-molecule drugs. It also includes perspectives on possible future applications that may improve safety and efficacy and facilitate diversification of the DESs to other clinical applications.
Neural changes in acute arthritis in monkeys. I. Parallel enhancement of responses of spinothalamic tract neurons to mechanical stimulation and excitatory amino acids

Abstract Somatosensory neurons of the spinal cord, including projection neurons, become hyperexcitable to mechanical stimuli during the development of experimental arthritis in rats and cats and hence are suggested to participate in the generation of arthritic hyperalgesia in humans. The experiments described here show a potentiation of the responses of spinothalamic tract (STT) neurons in monkeys during the development of an acute arthritis. The results demonstrate that the responses of STT neurons to mechanical stimuli and to iontophoretically applied excitatory amino acids (EAAs), particularly those acting at non -N- methyl - d - aspartate (non-NMDA) receptors, become enhanced during the development of inflammation produced by intra-articular injection of kaolin and carrageenan. Since the enhancement of both responses follows a similar time course, the results of this work suggest a role for EAAs in the hyperalgesia associated with arthritis and hence may provide a possible pharmacologic target for alleviation and/or prevention of arthritic pain.
Exploring the Folding Landscape of Lambda Repressor with Microfluidic Mixing

The folding kinetics of the λ-repressor protein have been explored with an ultrafast microfluidic mixer with a mixing time of 4 microseconds. Mutants with high stability (Tm=73°C), medium stability (Tm=54°C), and low stability (Tm=47°C) were tested and found to have an Arrhenius rate dependence around the cold denaturation temperature. Additionally, a surprising increase in molecular rate as the temperature approaches the heat denaturation temperature was also observed. Finally, the medium and low stability mutants exhibit a fast (molecular) rate which is not detected by T-jump experiments. These results suggest that chemical denaturation samples different pathways in the folding landscape than heat denaturation.
Strategy-based behavioural biometrics: a novel approach to automated identification

Behavioural intrusion detection is a frequently used for insuring network security. We expand behaviour based intrusion detection approach to a new domain of game networks. Specifically, our research shows that a behavioural biometric signature can be generated based on the strategy used by an individual to play a game. We wrote software capable of automatically extracting behavioural profiles for each player in a game of Poker. Once a behavioural signature is generated for a player, it is continuously compared against player's current actions. Any significant deviations in behaviour are reported to the game server administrator as potential security breaches.
Voter turnout and the benefits of voting

A model of voting behavior is developed that predicts that individuals vote if the absolute value of voting for or against a referendum exceeds the cost of voting. The results obtained from examining voting on city-county consolidation referenda and in New York state (1) provide support for the relatively untested prediction that turnout rises as the absolute value of the mean gains resulting from an electoral outcome increase and (2) augment the evidence that turnout rises as the probability of altering an electoral outcome increases and falls as the cost of voting rises.
Abstract 2169: Diabetes and pancreatic cancer survival: a prospective cohort study

Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Background: Diabetes is a risk factor for pancreatic cancer; however, its association with survival from pancreatic cancer is poorly understood. Because diabetes is a para-neoplastic manifestation of pancreatic cancer, it is vital for studies evaluating this association to establish history of diabetes before pancreatic cancer diagnosis, but such studies are lacking. Our objective was to investigate for the first time the association of diabetes with survival among pancreatic cancer patients in a cohort-based study where diabetes history was ascertained before pancreatic cancer diagnosis. Methods: We evaluated survival by baseline (1993-2001) self-reported diabetes history (n=62) among 504 participants that developed exocrine pancreatic cancer within the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. The PLCO Screening Trial is a randomized, two-armed, controlled trial that enrolled 154,901 men and women aged 55-74 years from 10 centers in the United States between November 1993 and July 2001. Pancreatic cancer stage was abstracted at the PLCO centers in categories of localized, locally advanced, and metastatic in 2010 from previously collected pathology reports and medical records used for cancer confirmation. Information on deaths and causes of death were obtained by linking the study population to the National Death Index. Hazard ratios (HRs) and 95% confidence intervals (CIs) for mortality were estimated using Cox proportional hazards model, adjusted for age, body mass index, race, smoking, and stage. Results: Median survival was shorter among those with diabetes (92 days) than those without diabetes (139 days, p-value=0.05). The multivariable adjusted HR for mortality comparing participants with diabetes to those without was 1.52 (95%CI 1.13-2.03, p-value <0.0001). After excluding those diagnosed with pancreatic cancer within 3 years of study enrollment, HR for mortality among those with diabetes was 1.40 (95%CI 1.05-1.99, p-value= 0.02). The association appeared to be stronger among men (HR=1.73, 95%CI 1.17-2.57, p-value= 0.006) than women (HR=1.36, 95%CI=0.84-2.22, p-value=0.216). Conclusion: In this survival analysis using incident cases ascertained from the PLCO prospective cohort, a history of diabetes prior to pancreatic cancer diagnosis was associated with higher mortality among pancreatic cancer patients. Studies characterizing the molecular mechanisms driving this association are needed as these can provide insights into relevant pathways that could be targeted for possible therapeutic interventions. Citation Format: Adetunji T. Toriola, Lara Dalidowitz, David Linehan, Rachael Stolzenberg-Solomon, Graham A. Colditz. Diabetes and pancreatic cancer survival: a prospective cohort study. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2169. doi:10.1158/1538-7445.AM2014-2169
Development of Relationship Competencies Through Guided Participation for Mothers of Preterm Infants

Objective To explore the effects of a guided participation (GP) intervention on mothers’ development of competencies in relating to their preterm infants in neonatal intensive‐care units. Design Mothers were enrolled in a randomized, longitudinal clinical trial to compare the effectiveness of GP with standard care teaching. Baseline data were collected when the infants were 29 weeks postconceptional age. The intervention (GP or standard care teaching) was administered, and relationship competencies were assessed through observation once per week for the next 6 weeks. Setting Two neonatal intensive‐care units in the Midwest. Participants A convenience sample of 16 mothers of low‐birthweight infants, 8 in each group. Interventions GP of mothers in relating to their infants in the context of caregiving activities was compared with standard care teaching. Results Mothers in the GP group had expectations and intentions that were more attuned and adaptive to their infants’ needs. In addition, the GP group was consistently higher in relationship competencies than the standard care teaching group. Conclusions GP can effectively support mothers in developing relationships with their preterm infants in the context of neonatal intensive‐care unit caregiving activities. JOGNN, 35, 358‐368; 2006. DOI: 10.1111/J.1552‐6909.2006.00049.x
Simultaneous Correction of Meridian Aberrations. II. Graphical Method

After establishment of the correct focal length, axial chromatic aberration, and Petzval sum, the meridian section aberrations (either third order or trigonometrically exact) of a lens system can be simultaneously corrected by a graphical method which uses data from digital traces. For a given object point and aperture zone, a lens system may afford several parameter sets which yield solutions of the problem, or there may be within a given range of parameters. The method finds all existing solutions, or, if there are none, will indicate the variations probably necessary to reach a parameter range which does contain solutions.
Obstructive sleep apnea is more common than central sleep apnea in methadone maintenance patients with subjective sleep complaints.

Objectives Opioid-dependent patients treated with methadone have subjective sleep complaints and disrupted sleep on polysomnography (PSG). Previous studies of sleep-disordered breathing (SDB) in this population have focused on central sleep apnea (CSA). Our objectives were to: (1) characterize obstructive sleep apnea (OSA) and CSA in patients in methadone maintenance treatment (MMT) for opioid dependence; (2) examine factors associated with SDB in this population; and (3) investigate whether SDB was related to severity of subjective sleep complaints in MMT patients with subjective sleep disturbances.
Catalyst development for ultra-deep hydrodesulfurization (HDS) of dibenzothiophenes. I: Effects of Ni promotion in molybdenum-based catalysts☆

Abstract A strong synergistic effect of nickel and molybdenum was observed for hydrodesulfurization (HDS) of dibenzothiophene (DBT), 4-methyldibenzothiophene (4-MDBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) over highly active Ni-MoS 2 /γ-Al 2 O 3 catalysts. The surface of the most active catalyst in this study was composed by Ni:Mo = 1:3, which was determined by XPS results. In addition, catalytic behavior indicates the presence of two different adsorption models accounting for the DDS (direct desulfurization) and the HYD (hydrogenation) pathways. The structure of the NiMoS active phase appears to be identical regardless of Ni/(Ni + Mo) ratio. The reaction sequence of the DDS pathways is DBT > 4-MDBT > 4,6-DMDBT due to the steric hindrance of methyl groups located adjacent to the sulfur atom of DBT, which prevents σ-bonding of the sulfur to the active site within the NiMoS phase. The reaction rates of HYD pathways are independent of the number of methyl groups, suggesting that the alkyl groups do not interfere the π-adsorption of DBTs on the active sites.
Getting Started and Getting Ahead: Career Dynamics of Immigrants

Abstract While immigration has continued to change demographic patterns in the United States and other countries, there has been little theory and research on the psychological processes underlying immigrants' adjustment to new careers. This article models the stress immigrants' experience from the demands, opportunities, and constraints they encounter as they embark on careers in their host country and the role that social support plays in facilitating acculturation. Immigrants' intercultural effectiveness, coping skills, and career motivation are considered as important moderators between acculturation stress and career outcomes. Directions for future research on the career dynamics on immigrants are discussed.
Validation of the MAC technique in dogs and rabbits

Minimum alveolar concentrations (MAC) are determined using one of the different noxious stimuli (clamping, electrical stimulation, or surgical incision), based on a study conducted in the 1960s with three dogs. This study compares different noxious stimuli applied in a randomized order in dogs (n = 10) anesthetized with isoflurane (I) and halothane (H), and in rabbits (n = 10) anesthetized with I. Anesthesia was induced with the anesthetic in oxygen and maintained with mechanical ventilation. End-tidal anesthetic (Fe′A) and CO2 (Pe′CO2) concentrations were monitored with a calibrated infrared gas analyzer. Pe′CO2 and body temperature were maintained within normal limits. Noxious stimuli included skin incision on the lateral chest (SI), clamping of the tail (TC), fore- (FC) and hindlimb paw (HC), and electrical current (50 V at 50 cycles second for 10 msecond pulses) applied to the fore- (FE) and hindlimb (HE), and oral mucosa (OE) (except rabbits). SI was applied first and only for the first two consecutive measurements using the up–down method for sequential sampling of quantal-response data. After an initial equilibration period of at least 20 minutes at an Fe′A of 1.4% (H) or 1.7% (I), the Fe′A was decreased in the first animal to 0.85% of H (dog) or 1% of I (dog and rabbit) and maintained for at least 20 minutes before the noxious stimuli. If the animal responded or did not respond, the stimuli were then tested at an Fe′A 0.1% higher or lower, respectively. The new Fe′A was kept constant for at least 20 minutes and the noxious stimuli repeated until purposeful movement ceased or returned, respectively. MAC was defined as the Fe′A mid-way between the value permitting and preventing purposeful movement. Data were analyzed using an anova. MAC for I in dogs was 1.27 ± 0.047 (mean ± SEM) for TC, FC, and HC; 1.36 ± 0.035 for OE; 1.35 ± 0.040 for FE and HE; and 0.99 for SI. MAC for H in dogs was 0.97 ± 0.028 for TC; 0.96 ± 0.032 for FC and HC; 1.04 ± 0.033 for OE, FE, and HE; and 0.73 for SI. MAC for I in rabbits was 2.08 ± 0.021 for TC, FC, and HC; 2.04 ± 0.023 for FE and HE; and 0.90 for SI. MAC for SI was significantly lower than the other methods. In conclusion, electrical current and clamping resulted in similar MAC values.
Epidermal growth factor in the submandibular gland and serum of mice with muscular dystrophy: chemical properties in dilute gland extracts.

Epidermal growth factor (EGF) has been measured in extracts of submandibular glands from mice with hereditary muscular dystrophy. RIA results show that adult male and female dystrophic mice have significantly less submandibular gland EGF than do unafflicted controls. Despite the differences in gland content of the protein, serum levels of EGF are similar in both dystrophic and control animals. Furthermore, submandibular gland concentrations of amylase are normal in the dystrophic mice, indicating that not all proteins synthesized by the glands are affected. Gel filtration studies reveal that the elution properties of EGF in extracts of glands from dystrophic and control animals are indistinguishable. Unexpectedly, the chromatographic profiles indicate that most of the EGF in gland extracts elutes as a low molecular weight protein when the molecule is studied at low, biologically active concentrations; only a small portion of the protein is associated with a high molecular weight complex. Under the same ex...
An efficient finite element technique for sound propagation in axisymmetric hard wall ducts carrying high subsonic Mach number flows

The general non-linear three-dimensional equation for acoustic potential is derived by using a perturbation technique. The linearized axisymmetric equation is then solved by using a finite element algorithm based on the Galerkin formulation for a harmonic time dependence. The solution is carried out in complex number notation for the acoustic velocity potential. Linear, isoparametric, quadrilateral elements with non-uniform distribution across the duct section are implemented. The resultant global matrix is stored in banded form and solved by using a modified Gauss elimination technique. Sound pressure levels and acoustic velocities are calculated from post element solutions. Different duct geometries are analyzed and compared with experimental results.
Computed tomography in the evaluation of clinical stage IB carcinoma of the cervix.

Abstract A retrospective analysis of 47 cases of clinical stage IB cervical carcinoma radiologically staged with computed tomography (CT) was undertaken. There were no cases where CT provided information which altered staging. In 5 cases, CT suggested extension of disease beyond the cervix which was not confirmed surgically or with other staging procedures. In 3 cases, one or more normal-sized obturator or internal iliac nodes with metastatic disease were discovered at surgery, but the high common iliac and periiaortic nodes were disease free. We conclude that routine use of CT in patients with clinical stage IB cervical carcinoma is not warranted unless the patient's body habitus precludes accurate physical examination.
Coupled power theorem and orthogonality relations for optical disk waveguides

A coupled power theorem is developed which is applied to radial line (disk) optical dielectric waveguides. This theorem is utilized to develop transverse-electric and transverse-magnetic orthogonality relations for modes propagating in perfect disk guides. Because azimuthal variation is easily controlled, the disk guide can be employed as a device for coupling energy from a single source to a large number of optical fiber guides.
The effect of two different freezing methods on the immediate post-thaw membrane integrity of adipose tissue derived stem cells

Abstract The effect of directional cooling on the immediate post-thaw membrane integrity of adipose tissue derived adult stem cells (ASCs) was investigated using a directional solidification stage (DSS). Several passages, including Passage-0 (P0), Passage-1 (P1), and Passage-2 (P2), obtained from the suspended culture of stromal vascular fraction (SVF) of the ASCs were used for this study. ASCs from P0, P1, and P2 were cooled at either 1, 5, 20, or 40 °C/min to an end temperature of −80 °C in the presence and absence of a cryoprotective agent (dimethylsulfoxide, DMSO). After freezing to −80 °C, the samples were thawed at 200 °C/min and the ability of the frozen/thawed ASCs to exclude fluorescent dyes was assessed. ASCs frozen using the DSS in the absence of DMSO were found to have a lower post-thaw cell membrane integrity (confidence level of 95%), when compared with the ASCs frozen in the presence of 10% volume/volume (v/v) ratio of DMSO. Intriguingly, a comparison with corresponding data for ASCs that were frozen using a commercially available controlled rate freezer (CRF) suggests that the directionally cooled ASCs (both in the absence and presence of DMSO) exhibit a significantly lower post-thaw cell membrane integrity (confidence level of 95%). This lowering of post-thaw cell membrane integrity for ASCs frozen using the DSS is postulated to be related to the differences in the nature and the associated damaging effects of ice crystals formed in the DSS vs. the commercial freezer.
Modeling nitrification inhibition

A quantitative structure-activity relationship (QSAR)-type model using groups and molecular connectivity has been developed on nitrification inhibition data derived from soil. The model has been tested against data derived from the inhibition of nitrification by specific nitrogen-containing pesticides. A second QSAR-type model developed from acclimated biodegradation data has been applied to the pesticides tested for nitrification inhibition. Data on the impact of specific compounds on activated sludge nitrification have been included and the soil model applied to these activated sludge data. In general, the agreement between predicted and observed values for nitrification inhibition was satisfactory. The agreement was only marginal with respect to the biological system data. The biodegradation model indicated that most of the strong inhibitors also would have prolonged existence in the open environment. The models are included in the paper as well as the specific methodology.
Growth versus function in the three-dimensional culture of single and aggregated hepatocytes within collagen gels

Hepatocytes require cell-cell and cell-substrate interactions to survive and function. Furthermore, cell proliferation and differentiated function are often reciprocally related activities, both of which are highly regulated in the liver microenvironment. To mimic the physiological organization of hepatocytes into multicellular plates, small hepatocyte aggregates containing an average of 4-6 cells were formed. The aggregates were suspended within three-dimensional collagen gels and compared to both single hepatocytes (suspended within collagen gels) and hepatocyte monolayers (on tissue culture polystyrene) over 6 and 10 days in culture. The comparison of aggregates with single cells represents a novel in vitro system for the study of hepatocyte cell-cell interactions. All hepatocyte-populated gels displayed almost identical patterns of cell behavior: hyperplastic or hypertrophic growth (indicated by DNA or protein concentration) coincided with the decline of phenotypic function (assessed by uric acid and albumin production), while functional recovery often accompanied the cessation of growth. However, aggregate cultures maintained an average of 2-fold higher concentrations of functional parameters than singlet cultures when cells were not involved in growth activities. Much higher concentrations of all cell parameters were sustained by gel-dispersed hepatocytes than by hepatocyte monolayers.
Thyroid function and lipids in patients with chronic renal disease treated by hemodialysis: With comments on the “free thyroxine index”

Abstract It is known that hypertriglyceridemia and abnormal thyroid function tests are common in patients with chronic renal disease treated by hemodialysis, but a possible association between these abnormalities has not been investigated. We measured serum thyroid hormone and lipid levels in one hundred patients receiving chronic hemodialysis. There were ten patients with elevations in serum thyrotropin (TSH). In the remaining patients with normal TSH, those receiving no drugs known to affect thyroid function had low mean values for thyroxine (T 4 ) and triiodothyronine (T 3 ), while the mean T 3 resin uptake (fraction of T 3 bound to resin, T 3 U) was normal, resulting in low mean values for free T 4 index (FT 4 I = T 4 × T 3 U) and free T 3 index (FT 3 I = T 3 × T 3 U). The depression in T 3 was greater than the depression in T 4 , so that T 3 T 4 ratios were also low. Androgen-treated male patients had the lowest T 3 and T 4 levels; their T 3 Us were high, presumably reflecting androgen-induced depression of T 4 -binding globulin, but their mean FT 4 I and FT 3 I were still lower than those of the other patients. Evidence is presented that the conventional T 3 U underestimates the proportion of free hormone when binding protein levels are low, and that a “new T 3 U,” the ratio of resin-bound T 3 to serum protein-bound T 3 , more accurately reflects the proportion of free hormone. Computing a “new FT 4 I,” as new T 3 U × T 4 , yielded values in the androgen-treated group similar to those of the other patients. Patients receiving propranolol had lower T 3 T 4 ratios than the other patients, presumably due to propranolol's inhibitory effect on peripheral conversion of T 4 to T 3 . No relationship was found between indexes of thyroid function and lipid levels. Subjects with high TSH levels had levels of triglyceride and cholesterol similar to the remaining patients. Among those with normal TSH levels, low levels of T 3 or T 4 did not correlate with abnormal lipid levels. It is concluded that thyroid hormone abnormalities do not explain the hypertriglyceridemia of patients on chronic hemodialysis. The frequency of low T 4 and T 3 values in such patients, in the absence of clinical evidence of hypothyroidism and, in most instances, in the absence of TSH hypersecretion, remains unexplained.
Pulmonary artery perfusion of doxorubicin with blood flow occlusion: pharmacokinetics and treatment in a metastatic sarcoma model

Background. We compared pharmacokinetics, toxicity, and treatment efficacy of pulmonary artery perfusion of low-dose doxorubicin with blood flow occlusion to intravenous doxorubicin injection in a metastatic sarcoma model in the rat. Methods. Animals received left pulmonary artery perfusion with 0.1, 0.2, or 0.5 mg/kg doxorubicin at a rate of 0.1 mL/min for 1 minute with 20 minutes of blood flow occlusion. Doxorubicin levels of the lung, heart, and serum were assayed. Body weights after treatment were recorded and right pneumonectomy was performed. The results were compared with those in rats that received 5 mg/kg doxorubicin by intravenous injection or the saline group. Pulmonary sarcoma metastases were treated with 0.5 mg/kg doxorubicin through lung perfusion or intravenously, or with saline solution. Results. Doxorubicin levels in the lung, heart, and serum were 112.1 ± 9.2 μg/g, 1.7 ± 0.2 μg/g, and 0.3 ± 0.1 μg/mL in the group with 0.5 mg/kg doxorubicin perfusion, versus 24.8 ± 1.9 μg/g, 10.1 ± 1.3 μg/g, and 0.7 ± 0.2 μg/mL in the intravenous group ( p Conclusions. This chemotherapy model has important pharmacokinetic advantages and causes an increased treatment response for pulmonary metastatic sarcoma with minimal systemic and local toxicity as compared with systemic doxorubicin administration.
Structural Differences between Aβ(1-40) Intermediate Oligomers and Fibrils Elucidated by Proteolytic Fragmentation and Hydrogen/Deuterium Exchange

The aggregation of amyloid-β protein (Aβ) in vivo is a critical pathological event in Alzheimer's disease. Although more and more evidence shows that the intermediate oligomers are the primary neurotoxic species in Alzheimer's disease, the particular structural features responsible for the toxicity of these intermediates are poorly understood. We measured the peptide level solvent accessibility of multiple Aβ(1-40) aggregated states using hydrogen exchange detected by mass spectrometry. A gradual reduction in solvent accessibility, spreading from the C-terminal region to the N-terminal region was observed with ever more aggregated states of Aβ peptide. The observed hydrogen exchange protection begins with reporter peptides 20-34 and 35-40 in low molecular weight oligomers found in fresh samples and culminates with increasing solvent protection of reporter peptide 1-16 in long time aged fibrillar species. The more solvent exposed structure of intermediate oligomers in the N-termini relative to well-developed fibrils provides a novel explanation for the structure-dependent neurotoxicity of soluble oligomers reported previously.
Capture of overspray powder paint in a wet booth system

A chemical treatment is developed to enable capture of powder paint in a wet booth system. The treatment paves the way for use of conventional wet booth systems in small or short-term powder paint applications where capital investment for dry powder booths is unfavorable. It is found that the powder paint collection in a wet booth is possible only in the presence of a suitable wetting agent in the boothwater. The selected wetting agent is polyoxyethylene-polyoxypropylene glycol, which is a low-foaming, nonionic, surface active agent, and found to have little interference with the detackifying and flocculating functions of a melamine-based chemical treatment program.
The Effect of Priscoline on the Clearance of Radiosodium from Muscle and Skin of Man in Normal and Diseased Limbs

The radiosodium clearance technic was used to measure the effect of Priscoline given intraarterially on the effective blood flow in muscle and skin of normal subjects and patients with peripheral vascular disease. The only clinically significant increase in the clearance rate of radiosodium (Na24) occurred in the skin; the clearance rate in muscle showed small increases which were constantly present but not considered to be clinically significant.
Acute renal failure followed by protracted, slowly resolving chronic uremia☆

Abstract A case of acute tubular necrosis which resulted in prolonged renal insufficiency accompanied by severe complications is described. After 1 yr partial spontaneous recovery of renal function occurred with improvement in the patient's neuropathy, anemia and secondary hyperparathyroidism. The possible mechanisms for this unusual course are discussed.
A Model for Agricultural Policy: An Addendum

IN TWO PREVIOUS articles I have developed a model of the farm labor market [1, 2]. One of the basic assumptions underlying this model was that capital is exogenous to the farm labor market. Geometrically this assumption boils down to a vertical supply curve whose shift, right or left, is determined by economic forces outside the farm sector. This model will be known here as Model A. Utilizing some accepted econometric estimates, I obtained estimates for parameters appearing in the two reduced equations for farm labor. In this addendum I replace the assumption of a vertical supply curve by a different assumption according to which the farm sector is confronted with a horizontal supply curve of capital. In other words, the farm sector has no influence over the cost of capital which is the exogenous variable. This model will be known as Model B. My main purpose is to compare the empirical estimates obtained by using the two different models. In addition to comparison per se, Model B yields a by-product: It enables us to examine the effects of a change in the price of capital on returns to farm labor and farm employment.
Boson core compressibility

Spatial inhomogeneity due to trapping typically obscures distinguishing observables. We propose that measures using boson double occupancy avoid trapping effects to reveal two key correlation functions. We define a boson core compressibility and core superfluid stiffness in terms of double occupancy. We use quantum Monte Carlo on the Bose-Hubbard model to empirically show that these quantities intrinsically eliminate edge effects to reveal correlations near the trap center. The boson core compressibility offers a generally applicable tool that can be used to experimentally map out phase transitions between compressible and incompressible states.
Self-assembly of protein aggregates in ageing disorders: the lens and cataract model

Cataract, neurodegenerative disease, macular degeneration and pathologies of ageing are often characterized by the slow progressive destabilization of proteins and their self-assembly to amyloid-like fibrils and aggregates. During normal cell differentiation, protein self-assembly is well established as a dynamic mechanism for cytoskeletal organization. With the increased emphasis on ageing disorders, there is renewed interest in small-molecule regulators of protein self-assembly. Synthetic peptides, mini-chaperones, aptamers, ATP and pantethine reportedly regulate self-assembly mechanisms involving small stress proteins, represented by human αB-crystallin, and their targets. Small molecules are being considered for direct application as molecular therapeutics to protect against amyloid and protein aggregation disorders in ageing cells and tissues in vivo . The identification of specific interactive peptide sites for effective regulation of protein self-assembly is underway using conventional and innovative technologies. The quantification of the functional interactions between small stress proteins and their targets in vivo remains a top research priority. The quantitative parameters controlling protein–protein interactions in vivo need characterization to understand the fundamental biology of self-assembling systems in normal cells and disorders of ageing.
Suppression of Transgene Silencing by Matrix Attachment Regions in Maize: A Dual Role for the Maize 5 ADH1 Matrix Attachment Region

Matrix attachment regions (MARs) are DNA sequences that bind an internal nuclear network of nonhistone proteins called the nuclear matrix. Thus, they may define discrete gene-containing chromatin loops in vivo. We have studied the effects of flanking transgenes with MARs on transgene expression levels in maize callus and in transformed maize plants. Three MAR elements, two from maize ( Adh1 5 � MAR and Mha1 5 � MAR) and one from yeast (ARS1), had very different effects on transgene expression that bore no relation to their affinity for the nuclear matrix in vitro. In callus, two of the MAR elements ( Adh1 5 � MAR and ARS1) reduced transgene silencing but had no effect on the variability of expression. In transgenic plants, Adh1 5 � MAR had the effect of localizing � -glucuronidase expression to lateral root initiation sites. A possible model accounting for the function of Adh1 5 � MAR is discussed.
Inflammatory Cytokines and Oxidized Low Density Lipoproteins Increase Endothelial Cell Expression of Membrane Type 1-Matrix Metalloproteinase

We investigated whether inflammatory cytokines or oxidized low density lipoproteins (Ox-LDL) present in human atheroma modulate extracellular matrix degradation by inducing membrane type 1-matrix metalloproteinase (MT1-MMP) expression. Cultured human endothelial cells (EC) constitutively expressed MT1-MMP mRNA and protein with enzymatic activity. Tumor necrosis factor-alpha (TNF-alpha), interleukin-1alpha, or interleukin-1beta caused a time-dependent increase in the steady-state MT1-MMP mRNA levels within 4 h of exposure, peaking about 4-fold by 6 h, and remaining elevated for 12 h. Increased MT1-MMP mRNA correlated with a 2.5-fold increase in MT1-MMP protein in EC membranes. Ox-LDL also increased MT1-MMP mRNA levels that varied with the duration of exposure and degree of LDL oxidation. The increase in MT1-MMP mRNA occurred within 6 h of exposure to Ox-LDL and peaked over 3-fold by 6 h. Ox-LDL, but not native LDL, increased MT1-MMP protein by 2-fold in EC membranes. A combination of TNF-alpha and Ox-LDL was additive in increasing MT1-MMP expression. Nuclear run-on assays showed that TNF-alpha or Ox-LDL augmented steady-state mRNA levels by increased transcription of the MT1-MMP gene. These findings indicate that activation of EC by inflammatory cytokines and/or Ox-LDL increase MT1-MMP expression. Since MT1-MMP promotes matrix degradation by activating pro-MMP-2, these results suggest a novel mechanism whereby cytokines or Ox-LDL may influence extracellular matrix remodeling.
Observations on basophil degranulation as an indicator of antigen-antibody reaction

Abstract These observations involve the study of basophil degranulation induced by the addition of antigen to the sera of patients or animals known to be sensitive to ragweed pollen and in subjects with good histories of allergic reactions to penicillin. An indirect technique described by Shelley was used, wherein basophils obtained from buffy coat of rabbit blood are used as indicator cells. Although nonspecific alteration of basophils was frequent from antigen or serum alone, the incidence of positive basophil degranulation from human ragweed-sensitive sera was 76 per cent, compared to 36 per cent in sera from nonsensitive controls. A greater percentage of positive reactions was noted with purified ragweed fraction, pool C, over whole ragweed antigen. Limited observations with an antiragweed rabbit serum and its homologous antigen showed positive responses only with a high concentration of antigen. In 36 patients with histories of previous penicillin reaction, the basophil response was positive in 36 per cent. In a group of 24 patients, in 44 per cent of whom penicilloyl-polylysine skin tests were positive, the incidence of positive basophil degranulation was 38 per cent. In the present study, nonspecific alterations in basophils interfered with efforts to quantitate the basophil response. While the results with ragweed-sensitive sera suggest a possible specificity directed toward a fraction of the ragweed antigen, total correlation with clinical sensitivity and reaginic antibody was not found. Many technical and theoretical problems require solution before the specificity of the basophil degranulation phenomenon can be confidently related to antigen-antibody reaction.
Tests of a Dynamic Systems Account of the A-not-B Error: The Influence of Prior Experience on the Spatial Memory Abilities of Two-Year-Olds

Recently, Smith, Thelen, and colleagues proposed a dynamic systems account of the Piagetian "A-not-B" error in which infants' errors result from general processes that make goal-directed actions to remembered locations. Based on this account, the A-not-B error should be a general phenomenon, observable in different tasks and at different points in development. Smith, Thelen, et al.'s proposal was tested using an A-not-B version of a sandbox task. During three training trials and three "A" trials, 2-year-olds watched as a toy was buried in a sandbox at Location A. Following a 10-s delay, children searched for the object. Across five experiments, children's (total N = 92) performance on the A trials was accurate. After the A trials, children watched as a toy was hidden at Location B, 8 to 10 inches from Location A. In all experiments, children's searches after a 10-s delay were significantly biased in the direction of Location A. Furthermore, this bias toward Location A decreased with repeated trials to Location B, as well as when children completed fewer trials to Location A. Together, these data suggest that A-not-B-type errors are pervasive across tasks and development.