cssi/SciSciGPT-SciSciNet huggingface dataset:
Specific Yield Storage Equation

Specific yield is part of the total porosity of a porous rock or sediment. The total porosity (total pore space) of a rock or sediment formation is much larger than the specific yield. Total porosity includes the fraction of pore space that is interconnected (called “effective porosity”) and porosity due to isolated pores. The effective porosity itself includes specific retention and specific yield. Specific retention is that volume fraction of water that is held back by adhesion and capillary forces, when an aquifer is drained. Specific yield is the amount of water that is actually available for groundwater pumping, when sediments or rocks are drained due to lowering of the water table. Specific yield depends on the distribution of pores, their shape, and grain size. The larger the surface area of the rocks or sediment particles per unit volume (“specific surface area”), the more water adheres to these surfaces. This decreases the specific yield in favor of specific retention. Fine-grained sediments have the largest specific surface area, the highest specific retention, and the lowest specific yield. Coarse-grained sediments have a very small specific surface area; hence, the specific retention is small, and the specific yield is large. Specific yield typically decreases with depth due to compaction of sediments. Keywords: specific yield; groundwater; aquifer; unconfined aquifer; confined aquifer; porosity
Skewed Primary Igκ Repertoire and V–J Joining in C57BL/6 Mice: Implications for Recombination Accessibility and Receptor Editing

Previous estimates of the diversity of the mouse Ab repertoire have been based on fragmentary data as a result of many technical limitations, in particular, the many samples necessary to provide adequate coverage. In this study, we used 5′-coding end amplification of Igκ mRNAs from bone marrow, splenic, and lymph node B cells of C57BL/6 mice combined with amplicon pyrosequencing to assess the functional and nonfunctional Vκ repertoire. To evaluate the potential effects of receptor editing, we also compared V/J associations and usage in bone marrows of mouse mutants under constitutive negative selection or an altered ability to undergo secondary recombination. To focus on preimmune B cells, our cell sorting strategy excluded memory B cells and plasma cells. Analysis of ∼90 Mbp, representing >250,000 individual transcripts from 59 mice, revealed that 101 distinct functional Vκ genes are used but at frequencies ranging from ∼0.001 to ∼10%. Usage of seven Vκ genes made up >40% of the repertoire. A small class of transcripts from apparently nonfunctional Vκ genes was found, as were occasional transcripts from several apparently functional genes that carry aberrant recombination signals. Of 404 potential V–J combinations (101 Vκs × 4 Jκs), 398 (98.5%) were found at least once in our sample. For most Vκ transcripts, all Jκs were used, but V–J association biases were common. Usage patterns were remarkably stable in different selective conditions. Overall, the primary κ repertoire is highly skewed by preferred rearrangements, limiting Ab diversity, but potentially facilitating receptor editing.
2‐(2,6‐Dimethylpiperidino)acetonitrile

[825-28-5] C9H16N2 (MW 152.27) InChI = 1S/C9H16N2/c1-8-4-3-5-9(2)11(8)7-6-10/h8-9H,3-5,7H2,1-2H3 InChIKey = NLOSAIIVENGARV-UHFFFAOYSA-N (α-lithiation affords a formyl anion equivalent) Physical Data: bp 99–102 °C/15 mmHg.1 Preparative Method: by the condensation of 2,6-dimethylpiperidine and Chloroacetonitrile.1
Receptors and giant interneurons signaling gravity orientation information in the cockroachArenivaga

1. The burrowing cockroachArenivaga is apprised of spatial position by two parallel rows of pendulous sensilla located on the ventral surface of each cercus (Hartman et al. 1979). 2. Electrophysiological recordings made during controlled displacements from primary orientation indicate that these receptors provide afference to two giant interneurons in each connective of the ventral nerve cord. 3. When the insect is maintained at primary orientation, except for sporadic neural activity evoked by air movements of the trichobothria, there is little neural activity. However, upon roll to the left two interneurons in the right connective produce action potentials (Fig. 3C). Upon roll to the right, two interneurons in the left connective fire. As the angle of roll is increased, the frequency of firing of action potentials increases. And, if the insect is maintained at a particular angle of roll, the appropriate interneurons fire tonically. Upon return to primary orientation, the interneurons cease firing. 4. If instead the cockroach is pitched from primary orientation, these same interneurons respond but in a different combination (Fig. 3A). Pitch forward causes the smaller interneuron of each connective to fire while pitch backward evokes neural activity from the larger interneuron of each connective. The frequency of firing increases with the angle of pitch, and when a pitch angle is maintained, the interneurons fire tonically. The interneurons are silenced upon return to primary orientation. 5. Rotation from primary orientation about other compass points permits determination of the receptive fields for these interneurons. Each interneuron is maximally responsive to rotations 45 ° from the longitudinal axis of the body with the receptive field approximately equivalent to one quadrant. The receptive fields overlap at the most stable (90–270 °) and least stable (0–180 °) axes of the insect (Fig. 6). 6. Extirpation experiments reveal that each row of receptors drives a particular interneuron (Fig. 5). Those in the medial row provide input to a large interneuron in the ipsilateral connective; the lateral row drives a smaller interneuron in the contralateral connective (Fig. 10). 7. These findings support the theory that cockroach cerci and cereal receptors function as equilibrium organs.
Acute estradiol treatment affects the expression of cocaine-induced conditioned place preference in ovariectomized female rats.

Abstract Women and female rodents are more responsive to the subjective effects of psychostimulant drugs of abuse compared to males. A growing body of literature supports a role for estradiol as a mechanism underlying these sex differences. However, little is known about the influence of acute elevations in levels of estradiol on drug conditioned behaviors. The aim of the present study was to evaluate the influence of an acute increase in systemic estradiol levels on the expression of cocaine conditioned place preference (CPP). Using a six day conditioning procedure, ovariectomized (OVX) female rats were conditioned with one of four doses of cocaine (2.5, 5, 10, or 15 mg/kg) to associate one of two large chambers of a CPP apparatus with cocaine or saline. Thirty minutes prior to the start of the CPP preference test, rats were pretreated with either 5 μg estradiol benzoate (EB) or peanut oil (PO). PO-treated rats expressed a significant preference for only the mid-range conditioning doses of cocaine (5 and 10 mg/kg). However, acute EB treatment resulted in a rightward shift in the cocaine dose–response curve; rats demonstrated a significant preference at only the moderate and high conditioning doses of cocaine (10 and 15 mg/kg). These findings demonstrate that acute elevations in estradiol may dampen the expression of conditioned responses to cocaine's secondary rewards at lower conditioning doses of the drug and facilitate CPP at higher doses while estradiol deficiency decreases the threshold dose of cocaine necessary to induce CPP.
Dopant-configurable polymeric materials for electrically switchable devices

We demonstrate that the conductivity of conjugated poly[2-methoxy-5-(2′-ethylhexyloxy)-p-phenylene vinylene] (MEH-PPV) can be configured by changing the dopant concentrations in the polymer electrochemically when an external electric field is applied. Two types of switchable devices were fabricated based on the dopant configurable polymer: (1) devices were composed of a layer of MEH-PPV and a layer of solid inorganic electrolyte (RbAg4I5) sandwiched between two metal electrodes; (2) devices were only composed of a MEH-PPV layer sandwiched between two metal electrodes, but the MEH-PPV layer was doped electrochemically with various anions such as hexafluorophosphate (PF6−) and trifluoromethanesulfonate (CF3SO3−). When a voltage above a threshold value is applied between the two metal electrodes, depending on polarity, the conductance of the devices can be electrically switched between its low-conductance “off” state and its high-conductance “on” state, and the devices can be switched on and off reversibly and repeatedly.
Phase Diagram and Physical Properties of H2O at High Pressures and Temperatures: Applications to Planetary Interiors

Here we discuss the phase diagram and physical properties of H{sub 2}O under pressure-temperature conditions relevant to planetary interiors. Recent studies show that the melting curve of H{sub 2}O increases rapidly above a recently discovered triple point at approximately 35 to 47 GPa and 1000 K, indicating a large increase in {Delta}V/{Delta}S (volume versus entropy change) and associated changes in the physical properties of H{sub 2}O at high pressures and temperatures. Existence of the triple point is thought to be associated with the formation of a superionic phase, dynamically-disordered ice VII, or extension of the ice VII-ice X phase boundary; although the precise pressure and temperature of the triple point, curvature of the melting line, and nature of the solid-solid transition below the triple point all remain to be further explored. The steep increase in the melting curve of H{sub 2}O at high pressures and temperatures has important implications on our understanding of planetary interiors. Depending on its curvature, the melting line of H{sub 2}O may intersect the isentropes of Neptune and Uranus as well as the geotherm of Earth's lower mantle. Furthermore, if the triple point is due to the occurrence of the theoretically predicted superionic phase, besides leadingmore » to significant ionic conductivity, fast proton diffusion would cause enhanced chemical reactivity and formation of complex compounds in these planets. For example, reaction of H{sub 2}O with iron and other metals to form metal hydrides such as FeH{sub x} could provide a mechanism for incorporation of hydrogen as a light element into Earth's core. The equation of state of water is also presented as it pertains to the properties of hydrous fluid and melt phases in the mantle.« less
Effect of coca‐leaf chewing on salivary progesterone assays

Although there is evidence for reduced fertility in Andean and Himalayan populations at higher altitudes, factors other than hypoxia may be primarily responsible. A valuable approach in the investigation of these fertility determinants is the use of salivary steroid assays. However, coca-leaf chewing—a ubiquitous practice among high altitude Andean populations—has negative consequences for the accurate measurement of ovarian steroids. This report evaluates the effects of coca-leaf chewing on assays of salivary progesterone. Study participants include naive and habitual users of coca leaf from La Paz and El Alto, Bolivia. Approximately 300 saliva samples were collected immediately before, during, and after coca-leaf chewing. The series includes samples with and without the alkaloid enhancer typically used by coca-leaf chewers. Coca chewing produces false salivary progesterone values that mimic luteal phase values. On the basis of this study, an appropriate protocol is developed for the collection of salivary samples in coca-leaf chewing populations. These results verify the feasibility of salivary assays, even for very difficult field conditions, and highlight the necessity of establishing suitable collection procedures before full field implementation of saliva sampling. © 1993 Wiley-Liss, Inc.
The Ups and Downs of Percent (and Some Interesting Connections).

Percent is a standardized ratio comparison that is often used to describe relative amounts of increase and decrease. In this paper, the nonsymmetric relationship between percent of increase and percent of decrease is explored in several ways. Beginning with a simple graphical representation of the relationship, the functional relationship is developed, with relative decrease expressed as a function of relative increase. Once expressed in the form f(x) = 100x/(100 + x), an immediate connection is made to two other topics commonly found within the study of rates—the work problem and the harmonic mean. Finally, successive percents of increase or decrease are shown to be everyday applications of the geometric mean. This deeper look at a common mathematical concept has uncovered rich structural relationships between topics that are often isolated in the curriculum.
AN OBJECT-ORIENTED RULE EVALUATION SCHEME FOR LOGICAL DATABASES IN MASSIVELY PARALLEL ENVIRONMENT

This paper extends an object-oriented approach to query processing in a deductive database with the consideration of deductive rules. In the object-oriented approach, each deductive rule and fact is represented as an active object, which acts with its own dedicated control sequences according to its functionality. All operations in objects are proceeded asynchronously. Since no object has global knowledge about the database, cooperation among objects is necessary in answering a query. While most of the conventional search strategies focus on some parts of the AND/OR tree expanded by a query at a time, the object-oriented approach can search down the AND/OR tree with a breadth-first strategy in parallel. As a result, all parts of the tree can be considered globally so that queries do not have to be evaluated in a tuple-by-tuple, operation-by-operation fashion; and the need of maintaining temporary relations can be eliminated.
Maternal risk factors in fetal alcohol syndrome: Provocative and permissive influences

We present an hypothesis integrating epidemiological, clinical case, and basic biomedical research to explain why only relatively few women who drink alcohol during pregnancy give birth to children with alcohol-related birth defects (ARBDs), in particular, Fetal Alcohol Syndrome (FAS). We argue that specific sociobehavioral risk factors, e.g., low socioeconomic status, are permissive for FAS in that they provide the context for increased vulnerability. We illustrate how these permissive factors are related to biological factors, e.g., decreased antioxidant status, which in conjunction with alcohol, provoke FAS/ARBDs in vulnerable fetuses. We propose an integrative heuristic model hypothesizing that these permissive and provocative factors increase the likelihood of FAS/ARBDs because they potentiate two related mechanisms of alcohol-induced teratogenesis, specifically, maternal/fetal hypoxia and free radical formation.
Immune status influences fear and anxiety responses in mice after acute stress exposure

Significant evidence suggests that exposure to traumatic and/or acute stress in both mice and humans results in compromised immune function that in turn may affect associated brain processes. Additionally, recent studies in mouse models of immune deficiency have suggested that adaptive immunity may play a role during traumatic stress exposure and that impairments in lymphocyte function may contribute to increased susceptibility to various psychogenic stressors. However, rodent studies on the relationship between maladaptive stress responses and lymphocyte deficiency have been complicated by the fact that genetic manipulations in these models may also result in changes in CNS function due to the expression of targeted genes in tissues other than lymphocytes, including the brain. To address these issues we utilized mice with a deletion of recombination-activating gene 2 (Rag2), which has no confirmed expression in the CNS; thus, its loss should result in the absence of mature lymphocytes without altering CNS function directly. Stress responsiveness of immune deficient Rag2−/− mice on a BALB/c background was evaluated in three different paradigms: predator odor exposure (POE), fear conditioning (FC) and learned helplessness (LH). These models are often used to study different aspects of stress responsiveness after the exposure to an acute stressor. In addition, immunoblot analysis was used to assess hippocampal BDNF expression under both stressed and non-stressed conditions. Subsequent to POE, Rag2−/− mice exhibited a reduced acoustic startle response compared to BALB/c mice; no significant differences in behavior were observed in either FC or LH. Furthermore, analysis of hippocampal BDNF indicated that Rag2−/− mice have elevated levels of the mature form of BDNF compared to BALB/c mice. Results from our studies suggest that the absence of mature lymphocytes is associated with increased resilience to stress exposure in the POE and does not affect behavioral responses in the FC and LH paradigms. These findings indicate that lymphocytes play a specific role in stress responsiveness dependent upon the type, nature and intensity of the stressor.
ONCOLYTIC POLIO/RHINOVIRUS RECOMBINANT (PVSRIPO) IN RECURRENT GLIOBLASTOMA (GBM): FIRST PHASE I CLINICAL TRIAL EVALUATING THE INTRATUMORAL ADMINISTRATION

BACKGROUND: PVSRIPO is the live attenuated, oral (SABIN) serotype 1 poliovirus vaccine containing a heterologous internal ribosomal entry site stemming from human rhinovirus type 2. PVSRIPO recognizes nectin-like molecule-5, an oncofetal cell adhesion molecule and tumor antigen widely expressed ectopically in malignancy. Within, we report on the ongoing phase I study evaluating the intratumoral convection-enhanced delivery (CED) of PVSRIPO. METHODS: Eligibility criteria for adult patients with recurrent supratentorial GBM included: 1-5 cm in diameter; ≥1cm away from the ventricles; ≥4 weeks after chemotherapy, bevacizumab (BEV) or study drug; adequate organ function; KPS >70%; and positive anti-poliovirus titer. Dose was rapidly escalated using a two-step continual reassessment method with anticipated accrual of 1 patient each on dose levels 1-4, and up to 21 patients at dose level 5. RESULTS: Thus far, ten patients have been treated (1 each at levels 1 and 3, 2 at level 2, 2 at level 4, 4 at level 5). One dose limiting toxicity (patient #8) was observed at level 5, a grade 4 intracranial hemorrhage at the time of catheter removal, which required de-escalation to level 4. Grade 2 and higher adverse events possibly related to study include: hemiparesis (grade 3, n = 1; grade 2, n = 1); lymphopenia (grade 3, n = 1); seizure (grade 2, n = 1); and one each of grade 2 diarrhea, paresthesia, dysphasia and hyperbilirubinemia. To date, 8 out of 10 patients are alive, with patients #1 and #2 now 20 and 19 months post PVSRIPO, respectively. Two BEV failure patients died six months post-infusion after hospice care was initiated due to persistence of baseline neurologic limitations. After observing prolonged steroid use in 5 of 7 patients treated on dose levels 3 to 5 and after results of new immunogenic analysis became available, it was agreed upon that dose level 2 is probably the optimal dose level. To date, the original study design has been amended to treat a total of 6 patients at dose level 2. CONCLUSIONS: Infusion of PVSRIPO via CED is safe thus far and observed efficacy outcomes are intriguing and warrant further clinical investigation. SECONDARY CATEGORY: Immunobiology & Immunotherapy.
Lipogenesis in adipose tissue from genetically obese rats.

Abstract Lipogenesis by adipose tissue and liver from lean, genetic obese and control obese rats was studied in vitro. More palmitate-1-14C was incorporated into lipid by adipose tissue of genetically obese rats than by control tissues. Glucose enhanced this effect but glycerol did not. Adipose tissue from genetic obese rats incorporated significantly more radioactivity from glycerol-14C into glycerideglycerol than adipose tissue from hypothalamic-obese rats in the presence of glucose and epinephrine. In homogenates of fat from genetic obese rats the addition of glycerol-3-phosphate stimulated a greater rate of lipid synthesis than in homogenates from lesioned-obese rats.
Requirement of AMPA Receptor GluR2 Phosphorylation for Cerebellar Long-Term Depression

Cerebellar long-term depression (LTD) is a model of synaptic memory that requires protein kinase C (PKC) activation and is expressed as a reduction in the number of postsynaptic alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptors. LTD was absent in cultured cerebellar Purkinje cells from mutant mice lacking the AMPA receptor GluR2 subunit and could be rescued by transient transfection with the wild-type GluR2 subunit. Transfection with a point mutant that eliminated PKC phosphorylation of Ser880 in the carboxy-terminal PDZ ligand of GluR2 failed to restore LTD. In contrast, transfection with a point mutant that mimicked phosphorylation at Ser880 occluded subsequent LTD. Thus, PKC phosphorylation of GluR2 Ser880 is a critical event in the induction of cerebellar LTD.
Agonistic behavior patterns in mice with streptozotocin-induced diabetes mellitus

To examine the effects of the altered metabolic and hormonal state of diabetes mellitus on rodent social behavior, male Swiss Webster mice made diabetic with streptozotocin were tested in a resident-intruder encounter. Isolated diabetic and control mice were introduced as intruders into the home cages of aggression-trained resident mice. The encounters were videotaped and analyzed for frequencies and durations of agonistic behavior. Diabetic mice responded to the aggression of resident mice with significantly less investigation and aggression and significantly more static defense and escape behaviors than did control mice. Resident mice responded to less aggressive diabetic mice with more aggression and social investigation. Plasma corticosterone levels were significantly higher in diabetic mice compared to controls and positively correlated with submissive behavior in diabetic mice. These findings indicate that social behavior is altered in male diabetic mice and support the hypothesis that elevated pituitary-adrenal cortical activity and/or metabolic changes affect behavior in male diabetic mice.
Tolerance and Condition in Regression Computations

Abstract Many regression programs include a tolerance test that does not allow a variable to enter the regression if its correlation with the previously entered variables exceeds a specified level. This is done to achieve computational stability by assuring that the correlation matrix C of the independent variables is not nearly singular. However, for any specified tolerance level, there is an example in which the entering variables pass the tolerance test but the computation is extremely unstable. A bound for the condition of C is p times the trace of C -1, which can be monitored instead of tolerance to assure stability.
Agglomeration of ash in fluidized beds gasifying coal: the godel phenomenon.

In a bed of anthracite or bituminous coke fluidized by air at 10 to 15 meters per second at 1200° to 1400°C, molten ash forms beads on the surface of a coke particle, some exuding from its interior. The beads merge and detach them-selves to grow further as loose fluidized ash agglomerates of low carbon content.
Competition and binding of arginine, imidazole, and aminoguanidine to endothelial nitric oxide synthase: aminoguanidine is a poor model for substrate, intermediate, and arginine analog inhibitor binding.

Abstract The oxygenase domains of nitric oxide synthases are unusual in that they contain at least three ligand binding sites; these correspond to the axial heme ligand position, the substrate binding site, and the pterin binding site. Ligands can occupy portions of a site or extend into regions of adjacent sites. Depending on the size, shape, and binding mode of ligands to these positions, cooperative and anticooperative interactions mediated conformationally and by binding domain overlap can be observed. In the present study we describe competition between arginine and imidazole at the axial heme ligand position; a second imidazole, which occupies part of the arginine site in some crystal structures, is too weak to contribute to the equilibria. All spectroscopic titrations using imidazole competition depend on displacement of the heme axial imidazole ligand, which drives the ferriheme low spin. Aminoguanidine, a partial arginine analog, has multiple binding modes. It is somewhat competitive with arginine; a ternary complex forms, but the K d for arginine increases from 1 to 15 μM in the presence of saturating aminoguanidine. Aminoguanidine competition with imidazole is very weak, amounting to approximately a factor of two increase in K d . This implies that aminoguanidine has multiple binding modes and is not well described as an arginine analog. The major binding mode occupies part of the binding site but does not extend into the imidazole axial ligand binding domain and probably corresponds to the crystal structure. The other binding mode is not significantly overlapped with the arginine site.
Biomarkers for diagnosis, monitoring of progression, and treatment responses in ankylosing spondylitis and axial spondyloarthritis

With the growing awareness of the impact of chronic back pain and axial spondyloarthritis and recent breakthroughs in genetics and the development of novel treatments which may impact best on early disease, the need for markers that can facilitate early diagnosis and profiling those individuals at the highest risk for a bad outcome has never been greater. The genetic basis of ankylosing spondylitis has been considerably advanced, and HLA-B27 testing has a role in the diagnosis. Knowledge is still incomplete of the rest of the genetic contribution to disease susceptibility, and it is likely premature to use extensive genetic testing (other than HLA-B27) for diagnosis. Serum and plasma biomarkers have been examined extensively in assessing disease activity, treatment response, and as predictors or radiographic severity. For assessing disease activity, other than C-reactive protein and erythrocyte sedimentation rate, the most work has been in examining cytokines (particularly interleukin 17 and 23), matrix metalloproteinase (MMP) markers (particularly MMP3). For assessing those at the highest risk for radiographic progression, biomarkers of bony metabolism, cartilage and connective tissue degradation products, and adipokines have been most extensively assessed. The problem is that no individual biomarkers has been reproducibly shown to assess disease activity or predict outcome, and this area still remains an unmet need, of relevance to industry stakeholders, to regulatory bodies, to the healthcare system, to academic investigators, and finally to patients and providers.
Unspoken rules of spoken interaction

Body language and familiar silent signals are as much a part of social experience as the conversation. Building systems to recognize and respond to such moves will propel interface technology to the next horizon.
Buckling Distortions and Mitigation Techniques for Thin-Section Structures

The underlying mechanisms associated with welding-induced buckling distortions are investigated using finite element procedures. Unlike stable type of welding-induced distortions which can be adequately captured by performing a thermo-plasticity simulation of actual welding procedures, local buckling distortions in welded structures are of an unstable type, which requires the use of appropriate buckling analysis procedures incorporating welding-induced residual stress state. With the underlying mechanisms in buckling distortions being established, two effective mitigation techniques were presented. One is trailing heat sink and the other is in-process synchronized rolling techniques. Detailed finite element simulations were performed to demonstrate how some of the important process parameters can be established in effectively reducing or eliminating the buckling distortions. The proposed techniques were also validated by laboratory welding trials. The underlying principles and potential applications of the distortion mitigation techniques are also discussed in light of the detailed finite element simulation results.
The delta-Eddington approximation for radiative flux transfer

Abstract This paper presents a rapid yet accurate method, the “delta-Eddington” approximation, for calculating monochromatic radiative fluxes in an absorbing-scattering atmosphere. By combining a Dirac delta function and a two-term approximation, it overcomes the poor accuracy of the Eddington approximation for highly asymmetric phase functions. The fraction of scattering into the truncated forward peak is taken proportional to the square of the phase function asymmetry factor, which distinguishes the delta-Eddington approximation from others of similar nature. Comparisons of delta-Eddington albedos, transnmissivities and absorptivities with more exact calculations reveal typical differences of 0–0.022 and maximum differences of 0.15 over wide ranges of optical depth, sun angle, surface albedo, single-scattering albedo and phase function asymmetry. Delta-Eddington fluxes are in error, on the average, by no more than 0.5%0, and at the maximum by no more than 2% of the incident flux. This computationally fa...
Cell surface turnover and shedding of fucosyl-glycoprotein in L6 cells

The disappearance of electrophoretically identifiable 3H-fucosylated glycoproteins from the cell surface of L6 cells is random and follows monophasic kinetics with a half-life of 9 hours. Approximately 47% and 53% of that loss is due to shedding and to degradation, respectively. Shedding also occurs with monophasic kinetics. Most of the electrophoretically identifiable-shed fucosyl-glycoproteins are released with homogeneous rates but do not represent a random sampling of the surface.
Fixed Effects and Bias Due to the Incidental Parameters Problem in the Tobit Model

Abstract The maximum likelihood estimator (MLE) in nonlinear panel data models with fixed effects is widely understood (with a few exceptions) to be biased and inconsistent when T, the length of the panel, is small and fixed. However, there is surprisingly little theoretical or empirical evidence on the behavior of the estimator on which to base this conclusion. The received studies have focused almost exclusively on coefficient estimation in two binary choice models, the probit and logit models. In this note, we use Monte Carlo methods to examine the behavior of the MLE of the fixed effects tobit model. We find that the estimator's behavior is quite unlike that of the estimators of the binary choice models. Among our findings are that the location coefficients in the tobit model, unlike those in the probit and logit models, are unaffected by the “incidental parameters problem.” But, a surprising result related to the disturbance variance emerges instead – the finite sample bias appears here rather than i...
Effects of low intensity UHF radio fields as a function of frequency

Thirty six naive male rats were used as Ss in two experiments to determine a possible relationship between frequency of low intensity ultra-high-frequency radio fields and activity level. In Experiment 1, a low frequency range (320 MHz – 450 MHz) was used, while a higher frequency range (770 MHz – 900 MHz) was used in Experiment 2. Identical low power levels were maintained for both experiments (.43 mW - .15 mW). Although the application of both high and low frequency ranges resulted in decreased activity, the lower frequencies were more effective in producing the activity change.
Dielectric properties of densified hardened cementitious materials

Abstract Relative permittivity (K′) and loss factor (tan D) of densified hardened cementitious materials with w/c=0.20 and heat treated to 500°C prepared with type I, type III, and a special microfine high silica content (MC500) cement have been compared as a function of temperature and frequency. These K′ and tan D values were found to be considerably lower for materials with microfine silicate cement than those with portland cements. Activation energies (Q) and relaxation times for the loss mechanism values were related to an ionic jump relaxation process. Lower K′ and tan D values have been measured for cement/polymer composites prepared with a methyl cellulose polymer and a lower w/c ratio of 0.17. The relative permittivity and loss factor of materials with a 60 vol. % of silica microspheres prepared with the silicate cement ranged from 5.4 to 5.1 and from 0.035 to 0.012 respectively.
Localization of the α7 integrin gene (ITGA7) on human chromosome 12q13: clustering of integrin and hox genes implies parallel evolution of these gene families

Abstract Expression of the α7 integrin gene (ITGA7) is developmentally regulated during the formation of skeletal muscle. Increased levels of expression and production of isoforms containing different cytoplasmic and extracellular domains accompany myogenesis. To determine whether a single or multiple α7 genes underlie the structural diversity in this alpha chain that accompanies development, we have examined the rat and human genomes by Southern blotting and in situ hybridization. Our results demonstrate that there is only one α7 gene in both the rat and the human genomes. In the human, ITGA7 is present on chromosome 12q13. Phylogenetic analysis of the integrin alpha chain sequences suggests that the early integrin genes evolved in two pathways to form the I-integrins and the non-I-integrins. The I-integrin alpha chains contain an additional sequence of approximately 180 amino acids and arose as a result of an early insertion into the non-I-gene. The I-chain subfamily further evolved by duplications within the same chromosome. The non-I-integrin alpha chain genes are localized in clusters on chromosomes 2, 12, and 17, and this closely coincides with the localization of the human homeobox gene clusters. Non-I-integrin alpha chain genes appear to have evolved in parallel and in proximity to the Hox clusters. Thus, the Hox genes that underlie the design of body structure and the Integrin genes that underlie informed cell—cell and cell—matrix interactions appear to have evolved in parallel and coordinate fashions.
Integration of gene expression profiling and clinical variables to predict prostate carcinoma recurrence after radical prostatectomy

BACKGROUND Gene expression profiling of prostate carcinoma offers an alternative means to distinguish aggressive tumor biology and may improve the accuracy of outcome prediction for patients with prostate carcinoma treated by radical prostatectomy. METHODS Gene expression differences between 37 recurrent and 42 nonrecurrent primary prostate tumor specimens were analyzed by oligonucleotide microarrays. Two logistic regression modeling approaches were used to predict prostate carcinoma recurrence after radical prostatectomy. One approach was based exclusively on gene expression differences between the two classes. The second approach integrated prognostic gene variables with a validated postoperative predictive model based on standard variables (nomogram). The predictive accuracy of these modeling approaches was evaluated by leave-one-out cross-validation (LOOCV) and compared with the nomogram. RESULTS The modeling approach using gene variables alone accurately classified 59 (75%) tissue samples in LOOCV, a classification rate substantially higher than expected by chance. However, this predictive accuracy was inferior to the nomogram (concordance index, 0.75 vs. 0.84, P = 0.01). Models combining clinical and gene variables accurately classified 70 (89%) tissue samples and the predictive accuracy using this approach (concordance index, 0.89) was superior to the nomogram (P = 0.009) and models based on gene variables alone (P < 0.001). Importantly, the combined approach provided a marked improvement for patients whose nomogram-predicted likelihood of disease recurrence was in the indeterminate range (7-year disease progression-free probability, 30–70%; concordance index, 0.83 vs. 0.59, P = 0.01). CONCLUSIONS Integration of gene expression signatures and clinical variables produced predictive models for prostate carcinoma recurrence that perform significantly better than those based on either clinical variables or gene expression information alone. Cancer 2005. © 2005 American Cancer Society.
Two Causal Theories of Counterfactual Conditionals

Bayes nets are formal representations of causal systems that many psychologists have claimed as plausible mental representations. One purported advantage of Bayes nets is that they may provide a theory of counterfactual conditionals, such as If Calvin had been at the party, Miriam would have left early. This article compares two proposed Bayes net theories as models of people's understanding of counterfactuals. Experiments 1-3 show that neither theory makes correct predictions about backtracking counterfactuals (in which the event of the if-clause occurs after the event of the then-clause), and Experiment 4 shows the same is true of forward counterfactuals. An amended version of one of the approaches, however, can provide a more accurate account of these data.
Serine and alanine mutagenesis of the nine native cysteine residues of the human A1 adenosine receptor

Abstract To examine the importance of the nine native cysteine residues in the human A 1 adenosine receptor, each cysteine was individually mutated to both serine and alanine. Saturation binding with the A 1 selective antagonist [ 3 H]DPCPX [8-cyclopentyl-1,3-di(2,3- 3 H-propyl)xanthine] resulted in a wild-type K d value of 0.92 nM. All serine and alanine mutants had similar K d values with the exception of serine/alanine mutations at Cys80 and Cys169. These two cysteine residues, which are highly conserved in G protein-coupled receptors and hypothesized to be linked through a disulfide bridge, demonstrated no detectable binding with [ 3 H]DPCPX. Both serine and alanine mutations at residues Cys80 and Cys169 resulted in receptors that were not detectable at the cell surface, as visualized by immunostaining. The serine/alanine mutants that did bind [ 3 H]DPCPX were characterized further through competition binding with the antagonist theophylline and the agonists NECA (5′- N -ethylcarboxamidoadenosine) and R -PIA [( R ) N 6 -phenylisopropyl adenosine]. The wild-type theophylline K i value was 2.41 μM, with the serine/alanine mutants having similar values. Wild-type NECA and R -PIA K i values were 0.74 μM and 97.0 nM, respectively. All mutants had K i values similar to wild-type with the exception of the Cys85Ser mutant, which had NECA and R -PIA values of 9.30 μM and 387.3 nM, respectively. These data show that Cys80 and Cys169 are absolutely required for delivery of the receptor to the plasma membrane. The Cys85Ser data indicate that although a cysteine is not required at this position, this residue may have an important role in ligand binding or for the structure of the receptor.
The Ca2+-Induced Structural Changes in Troponin In-Situ and In-Vitro: A FRET Study in Permeabilized Cardiac Muscle Fibers and Reconstituted Thin Filaments

Ca2+ binding to N-domain of cardiac troponin C (N-cTnC) initiates a cascade of structural changes within the thin filament. Among these changes, Ca2+-induced structural changes in troponin play a critical role in the allosteric regulation of the force-generating acto-myosin interactions. Although previous in-vitro studies have provided insight into these structural changes, how they are modulated by geometric and mechanical constraints conferred by the sarcomeric lattice structure in muscle tissue remains unknown. Recently we have developed a technique to quantitatively measure these structural changes in chemically-skinned muscle fibers using time-resolved FRET. In this study, we use this technique to monitor the Ca2+-induced N-cTnC opening in skinned muscle fibers and compare the obtained results to in-vitro studies. FRET donor (AEDANS) and acceptor (DDPM) modified double-cysteine mutant cTnC(13C/51C)AEDANS-DDPM was reconstituted into skinned muscle fibers to examine the N-cTnC opening. To study the effects of crossbridge and sarcomere-length based activation on this structural change, simultaneous measurements of fluorescence intensity decays and isometric tension were performed. Our results show that at steady-state, the Ca2+-induced N-cTnC opening is proportional to muscle force development, but the level of opening varies depending on the presence or absence of strong crossbridges (XB). For instance, in the presence of sodium vanadate (inhibitor of XB) no Ca2+-induced force response was observed, but Ca2+-induced opening of N-cTnC in the fibers was evident but with a smaller magnitude. Furthermore, when compared to in-vitro measurements, results from muscle fibers suggest that N-cTnC may adopt a more compact structure in muscle fibers due to the constraints imposed by the myofilament lattice structure. The effects of the myofilament lattice structure on structural dynamics of N-cTnC are also discussed in terms of FRET distance distributions.
Challenges Facing Statistical Genetics

(2000). Challenges Facing Statistical Genetics. Journal of the American Statistical Association: Vol. 95, No. 449, pp. 319-322.
The excitation of the heart and its modification under the influence of the chemical mediators and the cardiac nerves: I. Some general consequences of the one-factor theory

A generalized form of the one-factor theory is applied to the heart. It is found that the effects of acetylcholine and sympathin on the chronaxie can be accounted for only if the decay constant of the excitatory state increases in the presence of acetylcholine, and decreases in the presence of sympathin. With the assumption that this is the only effect of the chemical mediators, it is shown that upon application of acetylcholine to the heart the theory predicts: 1) a rise in the rheobase; 2) an increase in the time required for excitation by constant currents; 3) no change in the threshold with condensor discharges of brief duration; 4) a decrease in the spontaneous heart rate; 5) a sudden and complete inhibition of the spontaneous heart rate with excessive concentrations of acetylcholine. In general, the effects of sympathin predicted by the theory oppose those of acetylcholine.
Inflammatory breast carcinoma incidence and survival: The Surveillance, Epidemiology, and End Results program of the National Cancer Institute, 1975- 1992

BACKGROUND Little is known about the cause of inflammatory breast carcinoma (IBC), the most aggressive form of breast cancer. To the authors' knowledge, no studies have investigated whether IBC risk factors are different from those for breast carcinoma overall, and there has been only one report of IBC incidence and survival patterns. METHODS The authors used data from the Surveillance, Epidemiology, and End Results program of the National Cancer Institute for the period 1975-1992 to calculate age-adjusted incidence and survival rates for 913 white and 121 African American women with IBC involving dermal invasion of lymphatic ducts and 166,375 white and 13,674 African American women with other types of breast carcinoma (non-IBC). RESULTS Between 1975-1977 and 1990-1992, IBC incidence doubled, increasing among whites from 0.3 to 0.7 cases per 100,000 person-years and among African Americans from 0.6 to 1.1 cases. However, rates for African Americans varied due to the small numbers of IBC cases. The twofold increase in IBC incidence was higher than that observed for non-IBC during the same period (27% for African Americans and 25% for whites). IBC patients were significantly younger at diagnosis than non-IBC patients; and among both IBC and non-IBC patients, African Americans were younger than whites. Overall survival was significantly worse for IBC patients than for non-IBC patients and for African Americans than for whites. Among whites, 3-year survival improved more for IBC patients than for non-IBC patients between 1975-1979 and 1988-1992, increasing from 32% to 42% for IBC patients (P = 0.0001) and from 80% to 85% for non-IBC patients (P = 0.0001). CONCLUSIONS The disparities observed in incidence trends and age at diagnosis, particularly according to race, highlight the need for further investigation of the differences between IBC and non-IBC incidence. Cancer 1998;82:2366-2372. © 1998 American Cancer Society.
Attitudes toward a proposed reintroduction of Mexican gray wolves in Arizona

Abstract A survey of telephone‐households was conducted in Greenlee County, Arizona, within and surrounding the potential reintroduction site for Mexican gray wolves. Interviews of 130 residents showed that 22% supported wolf reintroduction, 58% opposed reintroduction, and 20% of respondents were undecided. Concerns about livestock and hardships for ranchers were cited most often as reasons for opposing wolf reintroduction, with human safety concerns second. Over 50% of reintroduction supporters believe that Mexican wolves are integral to the ecosystem and belong in the wild, and more than 30% said wolves are native to the area and should be returned to Arizona. Of those who opposed wolf reintroduction, 48% said that wolf reintroduction would have no impact on their lifestyle or business, and 64% were not aware that wolves would be considered experimental‐nonessential, and would be removed or destroyed if they caused injury to humans or livestock.