cssi/SciSciGPT-SciSciNet huggingface dataset:
A Somatic p.G45E GJB2 Mutation Causing Porokeratotic Eccrine Ostial and Dermal Duct Nevus

Importance Recent data demonstrated somatic mutations in GJB2 that were present in affected porokeratotic eccrine ostial and dermal duct nevus (PEODDN) tissue but absent in unaffected skin. Recognizing that PEODDN lesions can also appear in individuals with keratitis-ichthyosis-deafness syndrome and finding somatic mutations in their cohort, the authors concluded that somatic GJB2 mutation may cause PEODDN. By using whole-exome sequencing, we show that somatic GJB2 mutation alone is sufficient to cause PEODDN. Observations We performed whole-exome sequencing of paired blood and affected tissue samples isolated from a PEODDN lesion of a primary school-aged female patient with bands of hyperkeratotic-affected skin on the upper and lower extremities and trunk, and identified a single, protein-damaging p.Gly45Glu GJB2 mutation present in tissue samples but not in blood samples. Conclusion and Relevance Our results prove that somatic GJB2 mutation is sufficient to cause PEODDN. Dominantly inherited GJB2 mutations, including the p.Gly45Glu found in our case, have been shown to cause the severe multisystem disorder keratitis-ichthyosis-deafness syndrome. GJB2 encodes connexin 26, a gap junction protein, which permits intercellular ion and macromolecule flux. Individuals with somatic mosaicism are at risk for transmitting systemic disease to their offspring, and all individuals with PEODDN lesions should be counseled regarding the risk of having a child with keratitis-ichthyosis-deafness syndrome.
The incorporation of [14C] uracil and [14C] orotic acid into RNA in the cytoplasm of Amoeba proteus.

Abstract Nucleate and anucleate halves of Amoeba proteus were incubated with [ 14 C] uracil and [ 14 C] orotic acid. Autoradiographic analysis of cells after varying incubation periods indicated that both of these precursors were incorporated into cytoplasmic RNA in both nucleate and anucleate cells. It is suggested that the extensive incorporation of orotic acid derivatives into cytoplasmic RNA in anucleate cells represents good evidence for the capability of the cytoplasm for RNA synthesis in the absence of the nucleus.
Co-localization of CRF-ir perikarya and ACTH-ir fibers in rat brain

Abstract The distribution of corticotropin-releasing factor immunoreactive (CRF-ir) perikarya and ACTH-ir fibers was examined immunocytochemically, in adjacent sections, in the forebrain and brainstem of the rat. Throughout the nervous system, a remarkable concordance of localization of these neuropeptide system was noted. Both ACTH-ir fibers and CRF-ir perikarya were conjointly distributed within discrete hypothalamic, limbic and brainstem/autonomic regions previously demonstrated to contain opiate receptors and opiocortin (β-endorphin, β-LPH, ACTH) fibers. In view of the demonstrated interactions of CRF with the peripheral (pituitary) opiocortin system, these data suggest the possibility of a similar relationship of CRF and opiocortin systems in the central nervous system as well.
Myositis ossificans within the intercondylar notch treated arthroscopically

We present a case of intraarticular myositis ossificans in the right knee of a child. Myositis ossificans (MO), though relatively rare in childhood and even more uncommon within a joint, should be included in the differential diagnosis of an intra-articular mass when indicated by the typical clinical, radiographic, and histologic findings. An 11-year-old male presented with a history of trauma to his right knee. Four weeks after the initial injury, an MRI demonstrated evidence of an ACL rupture with a “cystic mass” within the intercondylar notch along the anterior surface of the torn ligament. At subsequent arthroscopy, the mass noted on MRI was removed. The histology was consistent with MO. The authors believe this to be the first case of MO in the intercondylar notch detected by MRI, treated by arthroscopy, and confirmed by histology.
RNAi Screening in Primary Human Hepatocytes of Genes Implicated in Genome-Wide Association Studies for Roles in Type 2 Diabetes Identifies Roles for CAMK1D and CDKAL1, among Others, in Hepatic Glucose Regulation

Genome-wide association (GWA) studies have described a large number of new candidate genes that contribute to of Type 2 Diabetes (T2D). In some cases, small clusters of genes are implicated, rather than a single gene, and in all cases, the genetic contribution is not defined through the effects on a specific organ, such as the pancreas or liver. There is a significant need to develop and use human cell-based models to examine the effects these genes may have on glucose regulation. We describe the development of a primary human hepatocyte model that adjusts glucose disposition according to hormonal signals. This model was used to determine whether candidate genes identified in GWA studies regulate hepatic glucose disposition through siRNAs corresponding to the list of identified genes. We find that several genes affect the storage of glucose as glycogen (glycolytic response) and/or affect the utilization of pyruvate, the critical step in gluconeogenesis. Of the genes that affect both of these processes, CAMK1D, TSPAN8 and KIF11 affect the localization of a mediator of both gluconeogenesis and glycolysis regulation, CRTC2, to the nucleus in response to glucagon. In addition, the gene CDKAL1 was observed to affect glycogen storage, and molecular experiments using mutant forms of CDK5, a putative target of CDKAL1, in HepG2 cells show that this is mediated by coordinate regulation of CDK5 and PKA on MEK, which ultimately regulates the phosphorylation of ribosomal protein S6, a critical step in the insulin signaling pathway.
Germanium ion implantation efficiency improvement with use of germanium tetrafluoride

Ion implantation of germanium in silicon wafers is often troubled by reduced ion source life due to use of germanium tetrafluoride (GeF 4 ) as a source material. The problem is mainly due to tungsten re-deposition, a result of a fluorine-induced halogen cycle initiated within the ion source. The halogen cycle is particularly pronounced in the case of GeF 4 by easy fragmentation of the molecule, as well as low utilization of germanium due to wide isotopic distribution of natural abundance GeF 4 . Through isotopic enrichment of 72GeF 4 , benefits such as enhanced ion implantation beam current, lower gas flow, and longer source life can be achieved versus natural GeF 4 . Additional benefits can be realized when using mixtures of GeF 4 with hydrogen (H 2 ). Data are presented that show the effect of H 2 content on beam current as well as on tungsten transport. Lastly, thermodynamics and stability results are presented for a single cylinder mixture of GeF 4 with H 2 .
Anthranilic diamides: A new class of insecticides with a novel mode of action, ryanodine receptor activation

Development of insecticides with unique modes of action is necessary to combat widespread insecticide resistance. A new class of insecticides has been discovered, the anthranilic diamides, that provides exceptional control through action on a novel target, the ryanodine receptor. Anthranilic diamides potently activate this receptor, releasing stored calcium from the sarcoendoplasmic reticulum causing impaired regulation of muscle contraction. Expression of a recombinant Drosophila ryanodine receptor in a lepidopteran cell line confers sensitivity to anthranilic diamides similar to that observed with native receptors. Ligand-binding studies with radiolabeled ryanodine and radiolabeled anthranilic diamide in Periplaneta americana reveal a single, saturable binding site for this chemistry distinct from that of ryanodine. Further, calcium mobilization studies using mammalian cell lines indicate anthranilic diamides exhibit >500-fold differential selectivity toward insect, over mammalian, receptors. Consequently, anthranilic diamides offer a novel pharmacological tool for calcium signaling research in addition to a unique alternative to existing pest-management strategies.
Nonoscillation of higher order functional differential equations

to be nonoscillatory. In the case of second-order ordinary equations a variety of such criteria are now known; for example, see [ 10-15 1. The development of nonoscillation criteria for functional equations has proven to be a considerably more difficult problem. Moreover, in view of an example recently constructed by Brands [ 11, the type of integrability criteria usually imposed on q(t) in the study of nonoscillation of ordinary equations will not yield nonoscillation for unforced functional equations. In fact, the only known nonoscillation criteria for functional equations are due to Graef et al. 191, Kusano and Onose [16], and Singh [22, 24, 261 for second-order equations, and Graef [B] and Singh [23] for higher order equations. Only the papers of Chen [2], Graef [7], and Staikos and Philos [29] contain such results for higher order nonlinear ordinary equations. The main result in this paper, Theorem 4, gives sufficient conditions for all solutions of Eq. (*) withf(x) sublinear and r(t) f 0 to be nonoscillatory. In order to prove this theorem we first discuss the asymptotic behavior of the oscillatory solutions of (*). In so doing, we are able to generalize recent results of Chiou [6], Graef et al. [9], Kusano and Onose [ 171, and Singh [ 19,21-261. In the last section of the paper we discuss some possible extensions of the theorems presented here.
The effect of the acetylcholine transport blocker 2-(4-phenylpiperidino) cyclohexanol (AH5183) on the subcellular storage and release of acetylcholine in mouse brain

The effect of the acetylcholine (ACh) transport blocker 2-(4-phenylpiperidino) cyclohexanol (AH5183) on the subcellular storage and release of acetylcholine was studied in mouse forebrain. Results indica3ed that AH5183 reduced the amount of ACh released from mouse forebrain minces by high K+ and veratridine over the identical concentration range as it inhibits the active transport of ACh into synaptic vesicles isolated from the electric organ of Torpedo. However, AH5183 did not block the K+- or veratridine-induced reduction of cytoplasmic (S3) ACh. Also, it did not block the loss of vesicular (P3 ACh caused by these depolarizing agents. It did, however, cause a disappearance of nerve ending ACh which was partially matched by a selective gain in the choline content of the P3 fraction. When minces of mouse forebrain were pretreated in high K+ to deplete the S3 and P3 fractions of their ACh content and then subsequently incubated in normal Krebs with [14C]choline, AH5183, at a concentration which reduces ACh release by 50%, did not affect the repletion of P3 stores with newly synthesized [14C]ACh. At somewhat higher concentrations, however, AH5183 reduced the amount of [14C]ACh in the P3 fraction without affecting the amount of [14C]ACh in the S3 fraction. At these concentrations it did not inhibit extracellular choline transport or ChAT activity. These results suggest that AH5183 may reduce the amount of ACh released from central cholinergic nerve terminals in response to depolarization through a combination of effects: (1) it may facilitate the breakdown or loss of ACh stored in the vesicular fraction; (2) it may also block the transport of newly synthesized ACh into the vesicular fraction.
On the decomposability of amalgamated sums

Abstract A detailed study of amalgamated sums is undertaken. Techniques are developed for determining when an amalgamated sum decomposes and a number of results are proven using these techniques.
The Surgical Resection and Chemotherapy of Metastatic Osteogenic Sarcoma of the Right Ventricle

The case report of a patient with metastatic osteogenic sarcoma of the right ventricle who had had an interscapulothoracic amputation in October, 1970, and a left lower lobectomy in June, 1973, for pulmonary metastasis is presented. The patient was hospitalized in October, 1974, with signs and symptoms of right ventricular outflow obstruction and arrhythmia, and cardiac workup established the presence of a right ventricular tumor. The lesion was successfully resected using cardiopulmonary bypass, and the diagnosis of metastatic osteogenic sarcoma was confirmed. The patient did well after the operation and returned to normal activity. She was placed on adjuvant Adriamycin (doxorubicin) chemotherapy, but 6 months later died of Adriamycin toxicity.
A simulation study of impacts of collaborative worm hole attacks in mobile ad hoc networks (MANETs)

Collaborative wormhole attacks create links within MANETs, and tunnel data to undesired destinations through the links. By doing so, wormholes compromise network performance, security, and may even bring down an entire network. We evaluate the impacts of collaborative wormhole attacks in MANETs, through simulations using AODV protocol in NS2. At first, we ran the simulation without collaborative wormhole nodes. We increased the number of nodes from 20 by an increment of 10 until 60 in every run. Every time we increased the node size, we ran the simulation 50 times and recorded the average. We then used the output collected to evaluate the average throughput and packet overhead. We repeated the same experiment with four collaborative wormhole nodes added to the network and collected results both for throughput and packet overhead. Our results show that there was a higher increase in throughput when no wormhole nodes were present than when collaborative wormhole nodes were introduced. For packet overhead, the simulations show that when collaborative wormhole nodes were added to the network, the packet overhead increased at a higher rate than when no wormhole nodes were present. The results show that collaborative wormholes negatively affect MANETs by reducing throughput and increasing packet overhead.
Kainate-Enhanced Release of d-[3H]Aspartate from Cerebral Cortex and Striatum: Reversal by Baclofen and Pentobarbital

A study was made of the actions of the excitant neurotoxin, kainic acid, on the uptake and the release of D-[2,3-3H]aspartate (D-ASP) in slices of guinea pig cerebral neocortex and striatum. The slices took up D-ASP, reaching concentrations of the amino acid in the tissue which were 14-23 times that in the medium. Subsequently, electrical stimulation of the slices evoked a Ca2+-dependent release of a portion of the D-ASP. Kainic acid (10(-5)-10(-3) M) produced a dose-dependent inhibition of D-ASP uptake. The electrically evoked release of D-ASP was increased 1.6-2.0 fold by 10(-5) and 10(-4)M kainic acid. The kainate-enlarged release was Ca2+-dependent. Dihydrokainic acid, an analogue of kainic acid with little excitatory or toxic action, did not increase D-ASP release but depressed D-ASP uptake. Attempts were made to block the action of kainic acid with baclofen and pentobarbital, compounds which depress the electrically evoked release of L-glutamate (L-GLU) and L-aspartate (L-ASP). Baclofen (4 X 10(-6)M), an antispastic drug, and pentobarbital (10(-4)M), an anesthetic agent, each inhibited the electrically evoked release of D-ASP and prevented the enhancement of the release above control levels usually produced by 10(-4)M kainic acid. It is proposed that 10(-5) and 10(-4)M kainic acid may enhance the synaptic release of L-GLU and L-ASP from neurons which use these amino acids as transmitters. This action is prevented by baclofen and pentobarbital. In view of the possibility that cell death in Huntington's disease could involve excessive depolarization of striatal and other cells by glutamate, baclofen might be effective in delaying the loss of neurons associated with this condition.
Review of recent evidence: potential interaction between clopidogrel and proton pump inhibitors.

Purpose. Recent evidence of a potential interaction between clopidogrel and proton pump inhibitors (PPIs) is discussed. Summary. The American College of Cardiology and the American Heart Association recommend use of gastroprotective agents, specifically PPIs, in patients receiving aspirin, a thienopyridine, or the combination who have an increased risk for recurrent gastrointestinal bleeding. Available evidence from one small, short-term, randomized, double-blind trial evaluating platelet aggregation and several observational studies suggests that there is a potential for a clinically significant interaction between clopidogrel and PPIs. A post hoc analysis of a large, randomized, double-blind trial found no evidence of a clinically significant drug interaction at 28 days, though a significant difference was observed at one year. The authors concluded that the use of PPIs, regardless of clopidogrel use, increases the risk of adverse cardiovascular events. Conclusion. Although data are limited, observational studies and prospective trials involving surrogate markers of platelet reactivity suggest a clinically significant interaction between clopidogrel and PPIs. Until further studies are completed to delineate the specifics of the interaction between clopidogrel and PPIs, the risks and benefits of concomitant treatment should be carefully weighed to determine the most appropriate treatment for each individual patient.
A study of mode conversion in an oxygen-hydrogen plasma

Linear mode conversion is considered between the ion‐cyclotron and magnetosonic branches in a multispecies plasma with parallel magnetic field gradients. The results are interpreted in terms of ion conic heating. The mode‐conversion coefficients are solved using perturbation theory, a phase integral approach, and saddle‐point theory. These results are compared with numerical calculations. The coefficients thus obtained demonstrate that substantial coupling occurs between the four propagating modes, and a definite absorption occurs. Such absorption corresponds to ion heating and is, under realistic circumstances, sufficient to explain the outflow and heating of ionospheric oxygen.
The behavioral treatment of a thirty year smallpox obsession and hand washing compulsion

Abstract A behavioral treatment using an in vivo variant of desensitization procedure with reading and writing as desensitizing agents was combined with extinction, social reinforcement of non-compulsive behavior and role-playing in the treatment of a 30-yr long washing compulsion with high frequency obsessional behavior in a 70-yr-old woman. A 24-month follow-up demonstrated continued success of the elimination of the obsessive behavior. The complex interrelationship of variables uncovered underscore the need for a careful behavioral analysis and skillful therapeutic intervention.
Large Intracranial Arteritis with Giant Cells in Systemic Lupus Erythematosus

Excerpt Neuropsychiatric manifestations in systemic lupus erythematosus have been reported extensively, but the central nervous system pathology has rarely been documented (1, 2). We studied the ca...
N-Methyl scanning mutagenesis generates protease-resistant G protein ligands with improved affinity and selectivity.

ment of the a-carbon side chain to the amide nitrogen atom often disrupts peptide function. We were interested in strategies that enhance proteolytic stability while preserving the function of the underlying peptide. Toward that end, we have explored the effect of inserting single N-methyl amino acids into functional peptides, a method we refer to as N-methyl scanning mutagenesis. Our hope was to find one or more substitutions that enhance protease resistance while retaining binding affinity. We chose the G-protein-binding core-motif peptide DKLYWWEFL, which binds the heterotrimeric inhibitory G protein Gai1*GDP with good affinity (Kd=200 nm), as our model system. [4] Our strategy was to systematically construct nine variants of this peptide bearing a single N-methyl analogue of the natural residue at each position. One challenge we faced was that previous synthetic methods for incorporating N-methyl residues involved long multistep reactions per coupling or A in low yields. [5,6] The synthetic difficulty is the result of coupling the secondary amine of an N-methyl peptide. [7] This coupling must go to near completion, in a short period of time to avoid diketopiperazine formation. [6] To couple Nmethyl residues we followed a strategy similar to Giralt and co-workers, [6] but used the additive pair O-(7-azabenzotriazol-1yl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (HATU)/ 1-hydroxy-7-azabenzotriazole (HOAt). Coupling each N-methyl amino acid goes to near completion in 20 min in one step with no preactivation for all residues we tested. As a result, we were able to construct the N-methyl peptides reliably with a final yield of 20‐25% (Table 1).
Nearly-lossless autoregressive image compression

Abstract A flexible accurate technique for improving image compression properties with linear image compressing transforms is presented. This is a reliable iterative algorithm for the nearly-lossless autoregressive (NLAR) compression of images, which permits control of errors produced in each pixel intensity while preserving the original image intensity range. The convergence of this new algorithm is demonstrated, both theoretically and numerically. Its relationship to other types of nearly-lossless compression, as well as to traditional lossless and lossy approaches, is discussed.
Use of background inorganic arsenic exposures to provide perspective on risk assessment results.

Abstract Background exposures provide perspective for interpreting calculated health risks associated with naturally occurring substances such as arsenic. Background inorganic arsenic intake from diet and water for children (ages 1–6 years) and all ages of the U.S. population was modeled stochastically using consumption data from USDA, published data on inorganic arsenic in foods, and EPA data on arsenic in drinking water. Mean and 90th percentile intakes for the U.S. population were 5.6 and 10.5 μg/day, assuming nationwide compliance with the 10 μg/L U.S. drinking water standard. Intakes for children were slightly lower (3.5 and 5.9 μg/day). Based on the current EPA cancer slope factor for arsenic, estimated lifetime risks associated with background diet and water at the mean and 90th percentile are 1 per 10,000 and 2 per 10,000, respectively. By comparison, reasonable maximum risks for arsenic in soil at 20 (higher typical background level) and 100 mg/kg are 4 per 100,000 and 2 per 10,000, using EPA default exposure assumptions. EPA reasonable maximum estimates of arsenic exposure from residential use of treated wood are likewise within background intakes. These examples provide context on how predicted risks compare to typical exposures within the U.S. population, thereby providing perspective for risk communication and regulatory decision-making on arsenic in the environment and in consumer products.
Mucosal Immune Response to Trivalent Live Attenuated Intranasal Influenza Vaccine in Children ♦ 815

Mucosal Immune Response to Trivalent Live Attenuated Intranasal Influenza Vaccine in Children ♦ 815
Direct Evidence for the Formation of a C−O Bond between Adsorbed Species

Direct X-ray photoelectron (XPS) and reflection−absorption infrared (RAIRS) spectroscopic evidence is reported here for the formation of a C−O bond via the thermal activation of adsorbed 2-propyl groups in the presence of chemisorbed oxygen on a Ni(100) single-crystal surface. The resulting species, a 2-propoxide intermediate, was identified by a shift in binding energy of some of the C 1s photoelectrons to approximately 285.3 eV and by the appearance of a C−O stretching vibrational mode in the infrared spectrum at about 1095 cm-1. The propoxide species forms around 200 K and remains on the surface until temperatures above 300 K, at which point they undergo β-hydride elimination to yield acetone.
Human capital and per capita product: A comparison of US states*

This article analyzes the extent to which human capital differences can explain the differences in gross state product (GSP) per capita levels between the richer and poorer states of the US. It uses 1990 Census and Bureau of Economic Analysis data on educational attainment, wage levels of different segments of the labor force, and GSP to compare New York – our representative rich state – with the poorest third of the states. The findings indicate that human capital differences explain at least 49% of the observed difference in GSP per capita between New York and each of the poor states.
Long-term expression of a fluorescent reporter gene via direct injection of plasmid vector into mouse skeletal muscle: Comparison of human creatine kinase and CMV promoter expression levels in vivo

Expression of a fluorescent reporter gene has been studied using two alternate promoters to transcribe the green fluorescent protein (gfp) from Aequorea victoria. The human cytomegalovirus (CMV) enhancer/ promoter or the human muscle-specific creatine kinase promoter (CKM) were inserted along with the gfp cDNA into a plasmid expression vector based on a modified adeno-associated virus genome. Naked plasmid DNA was injected into the hamstring muscle of mdx mice and gfp gene expression determined from frozen muscle sections taken at 4, 14, and 42 days postinjection. Fluorescence patterns obtained by photomicroscopy and quantitative fluorescence measurements indicated a near-linear increase in the accumulation of the gfp in skeletal muscle during the length of the study, with gfp expression at 42 days being roughly four times the values obtained at 4 days. The levels of expression of gfp from the CKM construct were consistantly higher than for the CMV construct. The CKM promoter/expression vector combination demonstrates significant potential for simple, direct delivery and long-term, high-level expression of genes in skeletal muscle.
Patient-specific analysis of the volume of tissue activated during deep brain stimulation

Despite the clinical success of deep brain stimulation (DBS) for the treatment of movement disorders, many questions remain about its effects on the nervous system. This study presents a methodology to predict the volume of tissue activated (VTA) by DBS on a patient-specific basis. Our goals were to identify the intersection between the VTA and surrounding anatomical structures and to compare activation of these structures with clinical outcomes. The model system consisted of three fundamental components: (1) a 3D anatomical model of the subcortical nuclei and DBS electrode position in the brain, each derived from magnetic resonance imaging (MRI); (2) a finite element model of the DBS electrode and electric field transmitted to the brain, with tissue conductivity properties derived from diffusion tensor MRI; (3) VTA prediction derived from the response of myelinated axons to the applied electric field, which is a function of the stimulation parameters (contact, impedance, voltage, pulse width, frequency). We used this model system to analyze the effects of subthalamic nucleus (STN) DBS in a patient with Parkinson's disease. Quantitative measurements of bradykinesia, rigidity, and corticospinal tract (CST) motor thresholds were evaluated over a range of stimulation parameter settings. Our model predictions showed good agreement with CST thresholds. Additionally, stimulation through electrode contacts that improved bradykinesia and rigidity generated VTAs that overlapped the zona incerta/fields of Forel (ZI/H2). Application of DBS technology to various neurological disorders has preceded scientific characterization of the volume of tissue directly affected by the stimulation. Synergistic integration of clinical analysis, neuroimaging, neuroanatomy, and neurostimulation modeling provides an opportunity to address wide ranging questions on the factors linked with the therapeutic benefits and side effects of DBS.
Mercury vaporization from corroded dental amalgam.

Abstract The purpose of this study was to determine the effect of corrosion and aging on the mercury vapor emission of dental amalgam in vitro . Amalgam electrodes were prepared from admixed, high-copper and conventional alloys and were aged for 1 week at 22°C or at 60°C to accelerate aging. The emission of mercury vapor was measured with an LDC mercury monitor after abrasion. The samples were corroded by anodic polarization in Ringer's solution and the mercury emission was remeasured. Mercury vapor emission declined exponentially after abrasion of the amalgams following the same rate law as oxidation of metals at low temperatures. There was a marked increase in the amount of mercury emitted from corroded samples when they were subsequently abraded. Accelerated aging of amalgams at 60°C resulted in greater resistance to corrosion and less mercury emission from the corroded samples. The conventional amalgam emitted less mercury vapor than the highcopper a amalgam regardless of whether the samples were experimentally corroded or uncorroded. A clinically corroded, conventional amalgam specimen exhibited the greatest amount of mercury vapor emission.
EFFECTS OF DIRECT, INTERMITTENT, AND VICARIOUS REINFORCEMENT PROCEDURES ON THE DEVELOPMENT AND MAINTENANCE OF INSTRUCTION‐FOLLOWING BEHAVIORS IN A GROUP OF YOUNG CHILDREN1

A group of young children (mean age: 2.5 yr) were instructed to follow different requests by a teacher in a day-care setting. Experiment I verified that mean group instruction following was low (10%) despite the opportunity for “observational learning”, i.e., the group of 12 children could watch a nonreinforced adult comply with the teacher's request. In Experiment II, when positive consequences were provided contingent on the adult model's behavior, mean group instruction following was relatively unaffected (14%). When direct reinforcement was given to four peer models, each for several sessions, the individual performances of three of the four peer models was elevated (from 50% to 80%); however, the mean performance of the remaining nonreinforced children (N = 7) was only moderately affected (21%). When reinforcement contingencies were again changed, so that each group member was provided direct, but intermittent reinforcement, mean group performance increased substantially to levels of over 70%. Once instruction following was high, presentation of reinforcement only to one peer model sufficed to maintain performance whereas earlier, this same vicarious reinforcement procedure had failed to establish group compliance. The maintenance of instruction-following behavior when reinforcement was applied solely to one child was interpreted mainly in terms of a high resistance to extinction following a history of intermittent reinforcement rather than a “vicarious”- or “self”-reinforcement mechanism. Finally, removal and re-introduction of group intermittent reinforcement, respectively, lowered performance (to levels of 40%) and elevated (to levels of 65%) the group's performance.
How the Dorsal gradient works: Insights from postgenome technologies

Gradients of extracellular signaling molecules and transcription factors are used in a variety of developmental processes, including the patterning of the Drosophila embryo, the establishment of diverse neuronal cell types in the vertebrate neural tube, and the anterior-posterior patterning of vertebrate limbs. Here, we discuss how a gradient of the maternal transcription factor Dorsal produces complex patterns of gene expression across the dorsal-ventral (DV) axis of the early Drosophila embryo. The identification of 60-70 Dorsal target genes, along with the characterization of approximately 35 associated regulatory DNAs, suggests that there are at least six different regulatory codes driving diverse DV expression profiles.
Disability Caused by Minor Head Injury

The authors studied 538 patients who had sustained minor head trauma, which was defined as a history of unconsciousness of 20 minutes or less, a Glasgow Coma Scale score of 13 to 15, and hospitalization not exceeding 48 hours. Of these patients, 424 were evaluated 3 months after injury. The follow-u
Identifying predictors of programming skill

. . . We have seen that computer programming is an art, because it applies accumulated knowledge to the world, because it requires skill and ingenuity, and especially because it produces objects of beauty -- Donald E. Knuth [1].
Transcriptomic Approach Predicts Tempo of Disease Progression in HIV-1 Infections

Clinical laboratories perform various tests to determine the HIV-1 infection status of patients, to evaluate the progression of disease, and to monitor the effectiveness of antiretroviral therapy. The pathogenesis of HIV-1–infected patients includes a rapid-progression subset that represents 10%–15% of the HIV-1–positive population (1). Identifying biomarkers that distinguish these rapid progressors (RPs)3 from chronic progressors (CPs) is critical for early clinical intervention (2). A number of biomarkers, including levels of CD4+ T cells, have been used to predict HIV-1 disease progression (2, 3). Moreover, certain host genetic and immunologic markers that have been revealed by the human genome programs are now being used beyond monitoring viral pathogens to help manage HIV-1 infections (3, 4). There is ample evidence that allele frequencies and relative hazard values of the Δ32 polymorphism of C-C chemokine receptor 5 (CCR5), the CCR5 promoter polymorphism P1, the 64I polymorphism of CCR2, T-cell receptor excision circles, Toll-like receptors 4 and 9, interleukin-7 receptor α, and HLA homozygosity produce …
Fast 2D fluid-analytical simulation of ion energy distributions and electromagnetic effects in multi-frequency capacitive discharges

A fast 2D axisymmetric fluid-analytical plasma reactor model using the finite elements simulation tool COMSOL is interfaced with a 1D particle-in-cell (PIC) code to study ion energy distributions (IEDs) in multi-frequency capacitive argon discharges. A bulk fluid plasma model, which solves the time-dependent plasma fluid equations for the ion continuity and electron energy balance, is coupled with an analytical sheath model, which solves for the sheath parameters. The time-independent Helmholtz equation is used to solve for the fields and a gas flow model solves for the steady-state pressure, temperature and velocity of the neutrals. The results of the fluid-analytical model are used as inputs to a PIC simulation of the sheath region of the discharge to obtain the IEDs at the target electrode. Each 2D fluid-analytical-PIC simulation on a moderate 2.2 GHz CPU workstation with 8 GB of memory took about 15–20 min. The multi-frequency 2D fluid-analytical model was compared to 1D PIC simulations of a symmetric parallel-plate discharge, showing good agreement. We also conducted fluid-analytical simulations of a multi-frequency argon capacitively coupled plasma (CCP) with a typical asymmetric reactor geometry at 2/60/162 MHz. The low frequency 2 MHz power controlled the sheath width and sheath voltage while the high frequencies controlled the plasma production. A standing wave was observable at the highest frequency of 162 MHz. We noticed that adding 2 MHz power to a 60 MHz discharge or 162 MHz to a dual frequency 2 MHz/60 MHz discharge can enhance the plasma uniformity. We found that multiple frequencies were not only useful for controlling IEDs but also plasma uniformity in CCP reactors.
Reflectance Wavebands and Indices for Remote Estimation of Photosynthesis and Stomatal Conductance in Pine Canopies

Abstract A field experiment determined the reflectance wavebands and indices which corresponded most strongly with photosynthetic capacity in a mixed stand of loblolly pine (Pinus taeda L.) and slash pine (P. elliottii Engelm. var. elliottii). The 5-year-old pines ranged in height from 3 m to 6 m and formed an optically dense canopy. Variation in photosynthetic capacity was amplified by soil application of the photosystem II herbicides diuron and bromacil to three of six experimental plots. Field measurements began on 23 August 1994 and continued through 20 December 1994. Canopy reflectance and leaf physiological data were acquired during mid to late morning for the sides of trees that generally received full sunlight. Net CO 2 assimilation rate first regressed significantly with reflectance on 5 October at wavelengths near 700 nm. In the 5 October to 2 December period, assimilation rates approximated photosynthetic capacity. When data were combined over this period, the ratio of reflectance at 701±2 nm with reflectance at 820±2 nm, or a normalized difference vegetation index (NDVI) computed from these values, regressed more strongly with photosynthetic capacity than first derivatives of spectral reflectance or wavelength at the red edge inflection point. The narrow band NDVI accounted for 17–29% more variability in the data than NDVI that were based on simulated TM, MSS, AVHRR, or SPOT bands. As a result of its linear relationship with assimilation rate, stomatal conductance to water vapor also regressed strongly with the narrow band ratio. These results are explained by the high sensitivity of reflectance near 700 nm to leaf chlorophyll content. The use of a narrow band centered near 700 nm along with a narrow or broad near-infrared band in vegetation indices should provide increased accuracy in estimates of photosynthetic capacity and corresponding conductance for optically dense canopies. Evaluation of the influence of leaf area index on these relationships will require further study.Published by Elsevier Science Inc., 1998
Enhancing one-dimensional charge transport through intermolecular π-electron delocalization: Conductivity improvement for organic nanobelts

Effective π-electron delocalization within a PTCDI nanobelt, for which the one-dimensional molecular arrangement is dominated by the cofacial π−π stacking, has been characterized by both electron spin resonance (ESR) spectrometry and current−voltage (I−V) measurement. The long-range π-electron delocalization enables dramatic enhancement of electrical conductivity of the nanobelt through external-charge doping. When immersed in saturated hydrazine vapor, about 3 orders of magnitude increase in conductivity was achieved for the PTCDI nanobelt, implying potential application of the nanomaterials in electrical sensing of reducing gaseous species such as organic amines.
Differentiating Enterococcus concentration spatial, temporal, and analytical variability in recreational waters

Monitoring recreational waters for fecal contamination is an important responsibility of water resource management agencies throughout the world, yet fecal indicator bacteria (FIB)-based recreational water quality assessments rarely distinguish between analytical, spatial, and temporal variability. To address this gap in water resources research and management protocol, we compare two methods for quantifying FIB concentration variability at a frequently-used beach on Lake Huron (Michigan, USA). The first method calculates differences between most probable number (MPN) and colony-forming unit (CFU) values derived from conventional analysis procedures. The second method uses the “raw data” from these analysis procedures in a Bayesian hierarchical model to explicitly acknowledge analytical variability and subsequently infer the relative significance of the effect of sampling location and time on in situ FIB concentrations. Results of the Bayesian analysis indicate that in situ FIB concentrations do not vary significantly over small spatial and temporal scales, and that observed differences in MPN and CFU values over these same spatial and temporal scales are due almost entirely to intrinsic variability introduced by laboratory analysis procedures. Our findings underscore potential opportunities for incorporating Bayesian statistical models directly into routine recreational water quality assessments and for advancing the state of the art in methods for protecting humans from waterborne disease.
Dislocation plasticity and phase transformations in Si-SiC core-shell nanotowers

Vapor-liquid-solid (VLS) Si nanotowers were coated with nanocrystalline SiC to form a Si-SiC core-shell composite. Due to a mismatch in the coefficients of thermal expansion (CTE), the Si core was under a compressive stress following the deposition. The composite tower was then cross-sectioned using focused ion beam milling, exposing the Si core. Indentation into the Si showed an increased toughness as a function of diameter compared to similar sized Si nanotowers and nanospheres. This result is explained through enhanced dislocation and phase transformation plasticity in the Si core from the CTE compressive stresses.
The 'North American shale composite' - Its compilation, major and trace element characteristics

North American shale composite (NASC) major element composition and compilation are presented, together with rare earth element (REE) redeterminations obtained by high precision analytical methods. The major element composition of the NASC compares closely with other average shale compositions, and significant portions of the REE and some other trace elements are contained in minor phases. The uneven REE distribution in NASC powder appears to yield the heterogeneity in analyzed aliquants. REE distributions of detrital sediments may to some extent be dependent on their minor mineral assemblages and the sedimentological factors controlling these assemblages.
Molecular epidemiology of parvoviruses

Abstract Molecular epidemiological studies of paruoviruses are complicated by the low levels of variation in the DNA genome of the viruses. Nevertheless, use of restriction enzyme analysis, DNA sequencing and monoclonal antibody analysis of epitope variation has been used to examine the distribution of virus strains in nature. Comparison of canine parvovirus and the related viruses from other carnivores showed that a number of variant strains of the viruses could be identfied by DNA sequence and antigenic analysis. Among CPV isolates some strains replaced previous antigenic types, while other variant antigenic types coexisted in nature. The viruses are apparently able to spread world wide, as most geographically separated viruses are not genetically distinct. The human B19 parvovirus has been examined by restriction enzyme analysis and limited DNA sequencing, and a variety of characteristic strains identified. Some were found world wide, while others were apparently found to be associated with certain countries.
Élaboration d'interfaces pour le commerce électronique : le problème des coûts de recherche de l'information appliquée

Cette recherche aide les createurs de sites web/internet a appliquer la connaissance sur les couts de recherche de l'information a l'elaboration de sites web/internet qui vendent des produits ou des services au consommateur. Le but de cette recherche est de predire comment des changements subtils dans la structure de l'interface avec l'utilisateur influencent les couts de recherche de l'information. Dans une etude empirique, les auteurs comparent 1411 choix faits par des sujets pour accorder leur clientele a un fournisseur en utilisant des annuaires papier et des annuaires electroniques. Les choix dependaient des couts de recherche de l'information imposes par les differents medias. En elaborant une base theorique pour predire les differences de couts de recherche de l'information, les auteurs aident les createurs a rendre leurs sites web/internet plus efficaces pour atteindre leurs objectifs marketing.
THE GROWTH OF SMALL FATIGUE CRACKS IN 7075–T6 ALUMINUM

— The growth of ‘small’, half-penny shaped surface fatigue cracks in a precipitation hardened aluminum alloy is compared with the growth of ‘large’cracks in fracture mechanics type specimens. It is found that the small cracks grow much faster than LEFM equivalent large ones, and also experience growth rate perturbations. It is suggested that localized microplasticity in nominally elastic specimens is responsible for the rapid growth of small cracks and that grain size limitations on the microplastic regions cause transient decelerations and sometimes permanent arrest, in crack growth.
Effect of polydispersity on the demixing pressures of polyethylene in near- or supercritical alkanes

Abstract Demixing pressures of a polyethylene sample of broad molecular-weight distribution ( M W = 121,000 , M w / M n = 4.43 ) in n-butane and n-pentane are reported. The results are compared with the demixing pressures of polyethylene standards with narrower molecular-weight distributions. For these systems at the concentrations investigated, the observed demixing pressures (cloud points) are greatly influenced by the high molecular-weight fractions of the polymer. The observations are further substantiated by measurements of the demixing pressures of synthetic blends (i.e., mixtures in different proportions) of polymer standards with narrow molecular-weight distributions.
MIMO broadcast DFE transceiver design with bit allocation under QoS constraints

This paper considers the joint design problem of linear precoder, decision feedback equalizer (DFE) and bit allocation for multi-input multi-output (MIMO) broadcast (BC) channels. The problem is formulated as the power minimization problem when the target bit rate and per stream symbol error rate (SER) are specified. For the two-user case, a particular class of joint triangularization (JT) can be applied to obtain the optimal design for the joint optimization problem with quality of service (QoS) constraints, namely, the Minimum Power JT broadcast DFE transceiver (MPJT). For arbitrary number of users, a suboptimal design, the Power Minimized QR DFE broadcast transceiver (PMQR), is also proposed. Numerical results are presented to demonstrate the performance of MPJT and PMQR transceivers under different QoS constraints. 1
Targeted disruption of the type 1 selenodeiodinase gene (Dio1) results in marked changes in thyroid hormone economy in mice.

The type 1 deiodinase (D1) is thought to be an important source of T3 in the euthyroid state. To explore the role of the D1 in thyroid hormone economy, a D1-deficient mouse (D1KO) was made by targeted disruption of the Dio1 gene. The general health and reproductive capacity of the D1KO mouse were seemingly unimpaired. In serum, levels of T4 and rT3 were elevated, whereas those of TSH and T3 were unchanged, as were several indices of peripheral thyroid status. It thus appears that the D1 is not essential for the maintenance of a normal serum T3 level in euthyroid mice. However, D1 deficiency resulted in marked changes in the metabolism and excretion of iodothyronines. Fecal excretion of endogenous iodothyronines was greatly increased. Furthermore, when compared with both wild-type and D2-deficient mice, fecal excretion of [125I]iodothyronines was greatly increased in D1KO mice during the 48 h after injection of [125I]T4 or [125I]T3, whereas urinary excretion of [125I]iodide was markedly diminished. From th...
Maximum likelihood track-before-detect with fluctuating target amplitude

An important problem in target tracking is the detection and tracking of targets in very low signal-to-noise ratio (SNR) environments. In the past, several approaches have been used, including maximum likelihood. The major novelty of this work is the incorporation of a model for fluctuating target amplitude into the maximum likelihood approach for tracking of constant velocity targets. Coupled with a realistic sensor model, this allows the exploitation of signal correlation between resolution cells in the same frame, and also from one frame to the next. The fluctuating amplitude model is a first order model to reflect the inter-frame correlation. The amplitude estimates are obtained using a Kalman filter, from which the likelihood function is derived. A numerical maximization technique avoids problems previously encountered in "velocity filtering" approaches due to mismatch between assumed and actual target velocity, at the cost of additional computation. The Cramer-Rao lower bound (CRLB) is derived for a constant, known amplitude case. Estimation errors are close to this CRLB even when the amplitude is unknown. Results show track detection performance for unknown signal amplitude is nearly the same as that obtained when the correct signal model is used.