cssi/SciSciGPT-SciSciNet huggingface dataset:
Deterministic priority inversion in Ada selective waits

Priority inversion is any situation where low priority tasks are served before higher priority tasks. It is recognized as a serious problem for real-time systems. In the course of building a performance model for multi-tasking Ada software, we have noticed that a fair algorithmic selection procedure may be likely to cause priority inversion in selective waits. This effect is in addition to the well-known priority inversion due to the FIFO nature of entry queues. As an illustration, we present a semi-formal partial model of the selective wait algorithm of the Alsys1 ' 286 DOS Ada Compiler v4.2, running under PC-DOS Version 3.30 on an IBM PC/AT2 The model was deduced from a series of experiments designed to illuminate the scheduling features of the system. These results may provide useful insight for users of this and other Ada compilers since priority inversion may occur in the way we describe in many systems. We also indicate one standard technique to avoid priority inversion at selective waits.
The Role of Cadmium and Nickel in Estrogen Receptor Signaling and Breast Cancer: Metalloestrogens or Not?

During the past half-century, incidences of breast cancer have increased globally. Various factors--genetic and environmental--have been implicated in the initiation and progression of this disease. One potential environmental risk factor that has not received a lot of attention is the exposure to heavy metals. While several mechanisms have been put forth describing how high concentrations of heavy metals play a role in carcinogenesis, it is unclear whether chronic, low-level exposure to certain heavy metals (i.e., cadmium and nickel) can directly result in the development and progression of cancer. Cadmium and nickel have been hypothesized to play a role in breast cancer development by acting as metalloestrogens--metals that bind to estrogen receptors and mimic the actions of estrogen. Since the lifetime exposure to estrogen is a well-established risk factor for breast cancer, anything that mimics its activity will likely contribute to the etiology of the disease. However, heavy metals, depending on their concentration, are capable of binding to a variety of proteins and may exert their toxicities by disrupting multiple cellular functions, complicating the analysis of whether heavy metal-induced carcinogenesis is mediated by the estrogen receptor. The purpose of this review is to discuss the various epidemiological, in vivo, and in vitro studies that show a link between the heavy metals, cadmium and nickel, and breast cancer development. We will particularly focus on the studies that test whether these two metals act as metalloestrogens in order to assess the strength of the data supporting this hypothesis.
Sample stacking in laboratory-on-a-chip devices

Abstract Sample stacking is a very important sample concentration technique. It has been used widely in capillary electrophoresis (CE). There are many different stacking techniques. One of the most popular techniques is called “field-amplified sample stacking” where an electric field discontinuity is set up across a concentration boundary. Charged analytes will then automatically stacked due to velocity changes after they cross the concentration boundary. There are several different strategies to perform sample stacking in microfluidic laboratory-on-a-chip devices. One could simply inject a plug of low concentration buffer containing sample into a channel surrounded by high concentration buffer. The electric field is then applied to stack the sample and move the whole plug into the separation channel. One could also stack the sample in a side channel adjacent to the separation channel. The disadvantage of this sample stacking technique is the difficulty in control of the precise location of stacked sample. We present a new sample stacking technique applied specifically to microfluidic laboratory-on-a-chip devices. Up to hundreds of fold increases in sample concentration can be achieved. We have also combined this stacking with electrophoretic separation in the same device.
Variations in urinary output of the lobster

Urinary rates were studied in cannulated juvenile lobsters. If animals were in intermolt and unfed, urinary rates were constant at daily rates of 2% and 20% of body weight in 100% and 75% seawater (SW), respectively. More than 4% of the body weight could be rapidly excreted as urine upon either feeding, forced drinking, or low salinity acclimation. These results indicate that the urinary bladders are usually filled with urine and that they are part of the body volume-regulating system. At ecdysis, however, urinary flow ceased when drinking rate increased, suggesting that the intermolt mechanism regulating body volume may have been altered. In 100% SW, drinking was necessary for lobsters to gain sufficient water to withdraw their claws at ecdysis. While in 75% SW, osmotic entry of water across the body surface alone was sufficient to permit a successful molt. These results indicate that water influx across the body surface may contribute to much of the water intake at ecdysis if the osmotic gradient is substantial and that the cessation of urinary flow contributes to the overall water balance at ecdysis.
Biological, psychological and social processes in the conduct disorders

Background: This paper reviews recent evidence on the causes and maintenance of aggressive and disruptive behaviours in childhood and adolescence. It considers the relative merits of several different ways of conceptualising such problems, in relation to the contribution of biological, psychological and social factors. Method: It focuses on conduct problems appearing in young childhood, which greatly increase the likelihood of persistent antisocial behaviours in adolescence and adult life in association with wider interpersonal and social role impairments. It considers the contribution of individual factors, including impaired verbal skills, deficits in executive functions, and an imbalance between behavioural activation and inhibition systems. These are viewed in interaction with commonly associated environmental disadvantages such as hostile or intrusive parenting. The roles of attributional biases, unrealistic self-evaluations, and insecure attachment are considered in relation to affect regulation, and effective social action. The contributions of the wider social environments of peers, neighbourhood and socio-economic conditions are evaluated. Conclusions: The paper concludes that, although considerable progress has been made over the past ten years, there is a need to further refine our conceptualisation of the behaviours to be explained, to develop a coherent theory of the causal and maintaining processes, and to carry out prospective studies with adequate numbers of high risk children.
Fundus autofluorescence in type 2 idiopathic macular telangiectasia: correlation with optical coherence tomography and microperimetry.

Purpose To use multiple imaging methods to investigate patients with type 2 idiopathic macular telangiectasia (IMT) at different disease severity stages so as to characterize and categorize disease progression through the full spectrum of disease phenotypes. Design Observational case series. Methods Twelve patients with type 2 IMT (22 eyes) examined with fundus photography, angiography, optical coherence tomography imaging, fundus autofluorescence (FAF), and microperimetry testing in an institutional setting. Results Eyes examined by multiple imaging methods were classified into 5 proposed categories (0 through 4): category 0 (fellow) eyes had normal results on all imaging methods. Category 1 eyes had increased foveal autofluorescence on FAF imaging as the only imaging abnormality. Category 2 eyes had increased foveal autofluorescence together with funduscopic and angiographic features typical of type 2 IMT. Category 3 eyes had additional evidence of foveal atrophy on optical coherence tomography, and category 4 eyes had all the above features plus clinically evident pigment clumping. FAF signal increased in intensity in the foveal region from category 0 through category 3, whereas category 4 eyes demonstrated a mixed pattern of increased and decreased FAF signal. Conclusions The findings here outline a sequence of progressive changes seen with multiple imaging methods in advancing stages of disease. Increase in foveal autofluorescence is an early anatomic change in type 2 IMT that may precede typical clinical and angiographic changes. Loss of macular pigment density in the fovea and a changing composition of fluorophores in the retinal pigment epithelium may underlie these changes on FAF in the fundus.
Singular Loci of Varieties of Complexes, II☆

Abstract In this paper we determine the singular loci of the irreducible components of the variety of complexes.
G0S2 modulates homeostatic proliferation of naïve CD8⁺ T cells and inhibits oxidative phosphorylation in mitochondria.

G0S2 modulates homeostatic proliferation of naive CD8 + T cells and inhibits oxidative phosphorylation in mitochondria
Zileuton improves memory deficits, amyloid and tau pathology in a mouse model of Alzheimer's disease with plaques and tangles.

The 5-lipoxygenase (5LO) enzyme is widely distributed within the central nervous system. Previous works showed that this protein is up-regulated in Alzheimer’s disease (AD), and plays an active role in the development of brain amyloidosis in the APP transgenic mice. In the present paper, we studied the effect of its pharmacological inhibition on the entire AD-like phenotype of a mouse model with plaques and tangles, the 3×Tg mice. Compared with mice receiving placebo, the group treated with zileuton, a specific 5LO inhibitor, manifested a significant improvement of their memory impairments. The same animals had a significant reduction in Aβ levels and deposition, which was secondary to a down-regulation of the γ-secretase pathway. Additionally, while total tau levels were unchanged for both groups, zileuton-treated mice had a significant reduction in its phosphorylation state and insoluble forms, secondary to a decreased activation of the cdk5 kinase. These data establish a functional role for 5LO in the pathogenesis of the full spectrum of the AD-like phenotype and represent the successful completion of the initial step for the preclinical development of 5LO inhibitors as viable therapeutic agents for AD.
Phenomenological Study of Pion Photoproduction with Polarized Photons

Expressions for the angular distributions and polarizations of pion photoproduction with polarized photon beams are derived from phenomenological production matrix. The experiments necessary for the complete determination of the multipole amplitudes are discussed in general, and in particular for the case in which only contributions up to $p$ waves in the final state are important. Complete determination requires circularly polarized beams. But if only $s$ and $p$ waves contribute, experiments with linearly polarized beams completely determine the production matrix. The knowledge of these amplitudes would allow the determination of the unknown $p$-wave scattering phase shifts (${\ensuremath{\alpha}}_{11}, {\ensuremath{\alpha}}_{13}, \mathrm{and} {\ensuremath{\alpha}}_{31}$) up to energies of about 300 Mev.Invariance properties of the angular distributions and polarizations are found and tables are given.
Nanofibrous Bio‐inorganic Hybrid Structures Formed Through Self‐Assembly and Oriented Mineralization of Genetically Engineered Phage Nanofibers

Nanofibrous organic–inorganic hybrid structures, where inorganic nanocomponents are formed or assembled within the aligned organic nanofibrous matrix, are important materials that can find applications in electronics, photonics, catalysis, and tissue engineering.[1–11] They not only provide a means for supporting and ordering the functional inorganic materials such as nanoparticles,[4–6,8] but also can serve as building blocks to further self-assemble into higher-order structures.[5,11,12] The common approaches to the synthesis of the nanofibrous organic-inorganic hybrid structures include electrospinning,[2,4,10] polymer-templating,[3] biotemplating,[5–7,11] and directional freezing.[1] As a matter of fact, the nanofibrous organic-inorganic hybrid structures are important building blocks in natural mineralized biomaterials. One of the best examples is the mineralized collagen fibrils constituting the extracellular matrix (ECM) of bone.[13] Bone is made of cells embedded in ECM, which is hierarchically organized from proteins, including type I collagen and non-collagenous proteins (NCPs) such as bone sialoprotein (BSP), and calcium hydroxylapatite (HAP, Ca10(PO4)6(OH)2). The collagen molecules (~1.5 nm wide and 300 nm long) are self-assembled into wider (up to 200 nm wide) and longer (several µm long) fibrils in a side-to-side and head-to-tail format, which are further hierarchically self-assembled to form much wider and longer collagen fibers (up to several tens µm wide and long).[14,15] HAP is found within the gaps and grooves of the collagen fibers with its c-axis preferentially along the collagen fibers.
A New Metadata Update Method for Fast Recovery of SSD Cache

In order to maintain data in an SSD (solid-state disk) cache durable after a crash or reboot, metadata information needs to be stored persistently in SSD. There are two typical metadata methods, update-write-update and write-update. While write-update method has one less SSD write operation than update-write-update for each write I/O, it limits the amount of cached data that can be used after a system crash. We present a design and implementation of a novel metadata update method for SSD cache, referred to as Lazy-Update Following an Update-Write (LUFUW). Our new metadata update method allows maximal amount of data in SSD cache available upon restart after a power failure or system crash with minimal additional writes to SSD. This capability makes restart run twice as fast as existing SSD caches such as Flash cache [1] that can only use dirty data in the cache after crash recovery. We present our prototype implementation on Linux kernel and performance measurements as compared with existing SSD cache solutions.
On the Hough Technique for Curve Detection

The usual Hough procedure for detecting curves embedded in digitized images involves a transformation from image space I to parameter space P. In this note we suggest that insight into this transformation may be enhanced by mapping P back into I.
Certainty, Doubt, Error: Comments On the Epistemological Foundations of Medieval Arabic Science1

The article comments on the epistemological foundations of medieval Arabic science and philosophy, as presented in five earlier communications, and attempts to draw some guidelines for the study of its social history. At the very beginning the notion of "Islam" is discounted as a meaningful explanatory category for historical investigation. A first part then looks at the applied sciences and notes three major characteristics of their epistemological approach: (a) they were functionalist and based on (b) experience and (c) observation. The second part looks at the theoretical sciences and notes that their epistemology was based on (a) geo
The DNA damage response: sensing and signaling

The protein kinases ATM and ATR are central components of the checkpoint mechanisms that signal the presence of damaged DNA and stalled replication forks. Recent studies have provided important new insights into how these kinases work together with their regulatory subunits, DNA repair proteins and adaptor proteins to sense abnormal DNA structures and implement the appropriate DNA damage response. These advances have provided a more detailed understanding of the interface between damaged DNA and the checkpoint sensor proteins.
An onlay technique for teeth in supraversion

Abstract A technique for onlaying teeth in supraversion has been described. Through proper selection and preparation, teeth in supraversion may be restored to normal function on a favorable plane of occlusion. Proper preparation procedures assure maximum retention and stability through the use of intracoronal and extracoronal parallel walls and line angles. Hygienic restoration margins result from placement above the free gingival margins, and desired tooth contours are produced more readily because the enamel remains on the buccal and lingual surfaces. The thickness of the gold in cuspal areas and the requirements for pulp protection have been stipulated.
The histology of the paraphysis of Amblystoma

The paraphysis of adult Amblystoma is made up of low columnar ependymal epithelit m which forms the paraphyseal tubules which end blindly and which communicate with one another by a common mouth with the third ventricle. Between the paraphyseal tubules venous sinusoids anastomose freely with one another forming a complicated rete. The sinusoids are made up entirely of endothelium. The blood supply to the paraphysis is entirely venous. Mitochondria were found in great abundance in the paraphysis of one female just previous to laying. Other specimens showed very few present. No conclusions can be drawn from these few observations as to the relationship between physiological activity and cellular structures. The Golgi apparatus was observed definitely localized between the nucleus and the ventricular end of the cell. Many large crystalloids were also observed to be localized between the nucleus and the ventricular end of the cell. Intercellular spaces are readily observed in sections stained with Mallory's connective tissue stain. Nassonow's osmic acid technique for the Golgi apparatus and Benda's crystal violet and alizarin stain clearly bring out the intercellular canals. Acid fuchsin stained particles within the intercellular spaces are more abundant toward the sinusoids than the cavities of the paraphyseal tubules. The intercellular canals have not been seen to communicate with either the sinusoids or the cavities of the paraphyseal tubules in any of the preparations observed.
Autotransplantation of avian parathyroid glands: an animal model for studying parathyroid function.

Abstract The parathyroid glands of chickens were autotransplanted and the return of parathyroid function following transplantation was determined. Parathyroidectomy (PTX) resulted in a marked hypocalcemia (5.2 ± 0.2 mg/dl) 4 hr following PTX. Plasma calcium (PCa) had declined to 4.3 ± 0.2 mg/dl 24 hr after PTX. Parathyroid glands were transplanted subcutaneously 24 hr after removal and 24 hr later, PCa had risen to 8.6 ± 0.5 mg/dl. Seven days after PTX, PCa increased to 10.3 ± 0.2 mg/dl and by 14 days was indistinguishable from control levels (10.8 ± 0.2 mg/dl vs. 11.0 ± 0.2 mg/dl, respectively). When chicks with transplanted glands were fed a low Ca (0.08%) diet for 2 weeks they were able to maintain plasma PCa at levels comparable to control birds. Removal of the transplanted glands resulted in marked decreases in PCa (from 9.7 ± 0.3 to 5.6 ± 0.8 mg/dl), in the fractional excretion of phosphate, in urine cAMP, and in renal 25OH-vitamin D 3 -1α-hydroxylase activity. Stepwise reductions in PCa and 1α-hydroxylase activity were produced in partially PTX and fully PTX chicks by removing part or all of the parathyroid tissue. These data suggest that the transplanted parathyroid tissue was the major source of circulating PTH and that it may be possible to produce different degrees of acute hypoparathyroidism by varying the amount of transplanted parathyroid tissue removed surgically. Chickens with transplanted parathyroid glands thus provide a convenient animal model in which to study parathyroid function in an avian species.
Amino acids as reduced carbon sources for Enterobacter cloacae during colonization of the spermospheres of crop plants

Abstract Enterobacter cloacae 501R3 grew in vitro and in natural soil on seven amino acids, commonly found in seed exudates, when these compounds were supplied as sources of reduced C. A collection of transposon mutants of E. cloacae strain 501R3, each deficient in some aspect of amino acid utilization, was used to determine the nutritional role of these amino acids during growth in spermosphere soil. Mutant strains M2 and M59 were reduced, or deficient in, the ability to use all seven amino acids when these compounds were supplied as sources of reduced C in vitro or in natural soil. However, these two strains were similar to strain 501R3 in growth on amino acids supplied as N sources and in other nutritional tests. Populations of strains M2 and M59 were significantly less ( P ≤ 0.05) than populations of strain 501R3 after 45 h in growth assays in corn and cucumber spermosphere soils. Growth by strain M2 was also significantly less than strain 501R3 in pea spermosphere soil ( P ≤ 0.05). However, growth by strains M2 and 501R3 was similar in bean, cowpea, radish and sunflower spermosphere soils while growth by strains M59 and 501R3 was similar in pea and radish spermosphere soils. The data are consistent with the hypothesis that amino acids are not required as sources of reduced C for E. cloacae during growth in spermosphere soil. The data suggest, however, that amino acids are important as sources of reduced C for growth in some, but not all, spermosphere environments.
A sensitive approach to map genome-wide 5-hydroxymethylcytosine and 5-formylcytosine at single-base resolution.

Mapping genome-wide 5-hydroxymethylcytosine (5hmC) and 5-formylcytosine (5fC) at single-base resolution is important to understand their biological functions. We present a cost-efficient mapping method that combines 5hmC-specific restriction enzyme PvuRts1I with a 5hmC chemical labeling enrichment method. The sensitive method enables detection of low-abundance 5hmC sites, providing a more complete 5hmC landscape than available bisulfite-based methods. This method generated a genome-wide 5fC map at single-base resolution. Parallel analyses revealed that 5hmC and 5fC in non-CpG context exhibit lower abundance, more dynamically, than those in CpG context. In the genic region, distribution of 5hmCpG and 5fCpG differed from 5hmCH and 5fCH (H = A, T, C). 5hmC and 5fC were distributed distinctly at regulatory protein-DNA binding sites, depleted in permissive transcription factor binding sites, and enriched at active and poised enhancers. This sensitive bisulfite conversion-free method can be applied to biological samples with limited starting material or low-abundance cytosine modifications.
Throughput-driven IC communication fabric synthesis

As the scale of system integration continues to grow, the on-chip communication becomes the ultimate bottleneck of system performance and the primary determinant of system architecture. In this paper we propose a throughput-driven synthesis methodology for on-chip communication fabrics based on optimized bus models. Compared with traditional delay-driven, wire-by-wire planning methods, the throughput-driven methodology provides a feasible and accurate system-level solution to address delay and congestion problems simultaneously during early-phase design planning. Unlike the conventional methods which are based on rather inaccurate RC models and simplistic delay metrics, in our methodology the communication fabrics are characterized in terms of realistic Partial Element Equivalent Circuits (PEEC) extracted from the multi-layer interconnects and transistor level transient analysis via SPICE-like tools. The characterized models facilitate a flexible interconnect fabric optimization engine that can be embedded into a system planner for throughput-driven synthesis. Furthermore, engineering trade-offs considering repeater area and interconnect power consumption are further considered as part of this methodology.
Glucuronidation of 3α-hydroxysteroids in vitro

Abstract In the presence of UDP-glucuronic acid and UDP-glucuronyltransferase, steroids with the 3α-hydroxy-5β-pregnane structure was converted into the corresponding C-3 β-D-glucosiduronates in 60–98%a yield, those with the 3α-hydroxy-5α-pregnane structure give yields of 20–30% and those of the 3β-hydroxy-5α series are not conjugated. Aldosterone, corticosterone and cortisone are inert toward conjugation. The conjugating procedure has been used to prepare steroidal glucosiduronates of high S.A. from tritiumlabeled 3α-hydroxy-5β-pregnanes.
Transmission and reflection electron microscopy of electromigration phenomena

Abstract The traditional model of electromigration damage resulting from grain boundary migration has been modified to include surface diffusion effects. The model is based on detailed TEM and SEM observations taken before, during and after current stressing. Significant effects were caused by the thin oxide overlayer that grows naturally on Al and Al-rich alloys during air exposure. The stresses applied by a typical thick passivation layer would surely modify the experimental results in ways that depend crucially on the exact experimental situation. Examples are also presented that show that where grain boundary migration was hindered or absent, surface diffusion phenomena became the dominant damage mechanism. The observations presented or referred to in this review and the interpretation of them should prove useful in helping our understanding of more complex electromigration phenomena.
Interrelationships of Parturition Problems, Production of Subsequent Lactation, Reproduction, and Age at First Calving

Abstract Data of 22,691 observations on parturition related problems (dystocia, calf mortality, milk fever, retained placenta, and mastitis) were collected from 27 cooperating California dairy herds. Age at first calving did not affect calving difficulty; thus, an optimal age for first calving was not identified. Decisions on breeding virgin heifers should be based on size of cow because of the effect of size of cow on difficulty at first parity. Small calves experienced greatest mortality at parities greater than one; however, large calves had greater mortality at first parity. Greater mortality for large calves at first parity was partially due to the increased difficulty associated with larger calves. Calving difficulty resulted in impaired reproductive performance (more days open, more services, and more days to first breeding) and decreased 30-day milk production but had no effect on 90-day milk production and 305-day mature-equivalent milk production. Dystocia, milk fever, and retained placenta occurred as a complex. Incidence of dystocia and calf mortality decreased with parity, and all other problems increased with parity.
The pyrolysis of trimethylgallium on a heated Si(100) substrate

Abstract Trimethylgallium (TMGa) is an important source gas for metalorganic chemical vapor deposition (MOCVD) and metalorganic molecular beam epitaxy (MOMBE). In the last three years, workers in three different laboratories have examined the pyrolysis of trimethylgallium (TMGa) on heated substrates. However, the mechanism of the decomposition process is still not understood. In this paper we consider the mechanism of the TMGa decomposition on a hot Si(100) substrate in a molecular beam system. It is found that at TMGa doses of 1 × 10 15 molecules/cm 2 or less, the decomposition process in the beam system is the same as that reported by Lee et al., Surface Sci. 216 (1989) 173, in studies where TMGa was dosed at low temperature and then the substrate was heated. However, at higher TMGa doses, the mechanism in the molecular beam system is different than the ones reported previously. It is possible to transiently populate a weakly bound state which we assign to TMGa adsorption in the second monolayer. If the sample is below 400 K, the TMGa in the second monolayer desorbs. However, at higher temperatures, the TMGa in the second monolayer can react to form a CH x group ( x = 3 or 4) and dimethylgallium. The dimethylgallium desorbs. However, some of the CH x groups remain bound to the substrate leading to extra carbon incorporation. There also is evidence for formation of traces of monomethylgallium above 500 K and an indication of methyl radical desorption above 650 K. Thus it seems that at high doses, the decomposition of TMGa on a hot substrate is somewhat different than the decomposition of a monolayer of TMGa which has been adsorbed at low temperatures and then heated. These results explain some of the apparent discrepancies in the literature.
Nicotine induces mitogen-activated protein kinase dependent vascular smooth muscle cell migration

Abstract Cigarette smoke, specifically the nicotine contained within, has been shown to cause ultrastructural changes in vascular endothelium resulting in the development of atherosclerosis. Our study examines the effects of nicotine on vascular smooth muscle cell (VSMC) migration and attempts to eludicidate the cellular mechanisms governing those effects. Bovine aortic VSMC were cultured in 10% fetal bovine serum (FBS) growth media and exposed to 10 −8 nicotine for varying periods of time. Boyden chamber chemotaxis assays and a scrape injury model using confluent cells were used to assess cell motility. Activation of the mitogen-activated protein kinases (MAPK), p38 and p44/42, was assessed using Western blotting methods. Nicotine, itself, did not cause significant VSMC migration. However, augmented migration was seen in nicotine-treated VSMCs (16.6±3-fold) and media (17.0±4-fold) with 10% FBS as chemoattractant. Inhibitors of p38 and p44/42 diminished this migration by 48.5±6% and 29.4±2%, respectively. Immunoblotting verified p38 and p44/42 activation with nicotine and inhibition with inhibitors of p38 and p44/42. Nicotine-treated endothelial cell (EC) conditioned media (CM) was shown to increase migration 20.3±l.l-fold. This chemotactic effect was diminished both with heat treatment and serial dilution. In conclusion, nicotine enhances the chemotactiveness of VSMC. This migration is mediated via the MAPKs p38 and p44/42. Nicotine causes EC production of a chemoattractant molecule that enhances VSMC migration.
Effects of neonatal treatment with 6-aminonicotinamide on basal and isoproterenol-stimulated ornithine decarboxylase activity in cerebellum of the developing rat

6-Aminonicotinamide (6-AN) is a nicotinic acid (vitamin B3) antagonist which, when administered to immature animals, has a profound influence on brain development. To explore the biochemical mechanisms which underlie these actions, we evaluated effects of 6-aminonicotinamide on ornithine decarboxylase, an enzyme involved in cellular replication and differentiation. The cerebellum of the neonatal rat was chosen for study because it represents a brain region which undergoes major maturational events postnatally. When given to neonatal rats, 6-aminonicotinamide (10 mg/kg, i.p., on days 1, 3, 5 and 7) caused a prompt and persistent inhibition of the enzyme well in advance of adverse effects on tissue weight or on general growth. In addition, the ability of the cerebellum to respond to trophic stimulation by a beta-adrenergic agonist, isoproterenol, was attenuated markedly. Assessment of cerebellar morphology indicated an early adverse effect of 6-AN on granule' cell division, resulting in eventual disruption of the characteristic laminar structure of this brain region. These data support the view that reduced ornithine decarboxylase activity and impairment of its reactivity to growth stimuli participate in the toxic effects of 6-aminonicotinamide on brain development.
Effects of professional development training on joint attention engagement in low‐quality childcare centers

This study carries forward the exploration of joint attention engagement in children from 18 to 24 months of age enrolled in ‘low‐quality’ childcare centers. Childcare providers and children were videotaped to capture social interactions in the classroom including duration and bids for joint attention. One‐half of 48 childcare providers were randomly assigned to receive professional development training (PDT) (the Focus‐Follow‐Talk® technique) designed to increase the frequency of joint attention. Three months after the PDT and three coaching visits for each subject in the treatment group, 30 minutes of videotape was recorded and coded for each childcare provider in the treatment and control groups. Significant findings were reported for the trained childcare providers on joint attention engagement duration and total bids for joint attention engagement. There was also evidence supportive of joint attention subtypes.
Magic Cells and Circuits: New Convergence of Memory and Logic Functions in Superconductor Devices

The finite speed of light sets a fundamental limitation for the time required to communicate between any remote memory and logic devices. This limitation alone implies that the latency of communication cycles between, say, 1-cm processor and memory chips is longer than 120 ps. To bypass this limitation, we propose a novel way of using SFQ cells and devices that eliminates the communication delays by storing and processing information in the same location. We introduce new objects (cells and devices) that store one of input operands, process it during a logic operation that might involve other operands, and replace the initially stored operand by the result of the logic operation. Because these objects execute both Memory And loGIC functions we nicknamed them MAGIC cells and devices. Physically each MAGIC object is either a single flip-flop or composed of flip-flops. MAGIC objects are compatible with, or even may constitute a part of, RSFQ technology. We discuss functional devices built of MAGIC cells. These devices are potentially faster, smaller in size, and have modest requirements for external memory. This is because the suggested functional circuits partly self-satisfy storage needs by utilizing their inherent ability for storing data.
Chronic anti-inflammatory drug therapy inhibits gel-forming mucin production in a murine xenograft model of human pseudomyxoma peritonei

Background Intraperitoneal accumulation of mucinous ascites in pseudomyxoma peritonei (PMP) promotes an inflammatory/fibrotic reaction that progresses to bowel obstruction and eventual patient demise. Cytokines and inflammation-associated transcription factor binding sites, such as glucocorticoid response elements and COX-2, regulate secretory mucin, specifically MUC2, production. We hypothesized that anti-inflammatory drugs targeting inflammation-associated pathways may reduce mucin production and subsequent disease morbidity in PMP.
Aerobic Responses of The Cornea to Topical Anesthetics

AbstractThe aerobic responses of the rabbit cornea to commonly used topical anesthetics, 1/2% proparacaine and 1/2% tetracaine, were studied with single and multiple dosing regimens. With single dosing, oxygen uptake rates increased 24.0% for proparacaine and 41.7% for tetracaine 30 min after application of 1 drop. The oxygen uptake rates for single dose application of proparacaine were significantly elevated (p < 0.05 paired Student's t-test) from the pre-exposure levels at every time interval except at the 60 min measurement, which was elevated 14.5% above pre-exposure but was not significantly different (p = 0.061 paired Student's t-test). The oxygen uptake rates found after one application of tetracaine were significantly increased at all measurements. Multiple dosing at 5 min intervals caused a gradual reduction in oxygen uptake rate that was only 64.8% of pre-exposure levels for proparacaine and 62.6% for tetracaine at 60 min after the initial application (p < 0.05 Student's t-test). Both agents cau...
Under-Representation of Older Adults in Cancer Registration Trials: Known Problem, Little Progress

The oncology literature from the last decade is replete with articleslamentingthescarcityofdatatoguidetreatmentdecisionsforthe elderly population with cancer. With the aging of the United States and worldwide population and the known association between older ageandcancer, 1 cliniciansandresearchersunderstandtheimportance of studying the efficacy and toxicity of cancer therapies in this at-risk population. The importance of this knowledge is highlighted by the US Food and Drug Administration in its Guideline for the Study of Drugs Likely to Be Used in the Elderly, 2 which advocates enrollment of older adults in clinical trials as a means to understand treatment effects among differing populations. Almostadecadeago,JournalofClinicalOncologyhighlightedthe under-representation of older adults in registration trials for new cancertherapiesfrom1992to2002.Talaricoetal 3 showedtheproportions enrolled onto registration trials versus the proportions in the overall populations age 65, 70, and 75 years were 36%, 20%, and9%comparedwith60%,46%,and31%,respectively.Theauthors surmised that decline in functional reserve, increased comorbid con
Debating how to fix health insurance.

The American Medical Association (AMA) agrees that a public-private partnership can solve the problem of the uninsured, but a single-payer system like that discussed by J. B. Richmond and R. Fein in their Editorial “Health insurance in the USA” (26 Sept., p. [1813][1]) is the wrong prescription
Update of a retrospective cohort study of changes in hip joint phenotype of dogs evaluated by the OFA in the United States, 1989-2003.

Objective— To determine whether there has been improvement in canine hip joint phenotype classifications of dogs whelped from 1989 to 2003 by the Orthopedic Foundation for Animals (OFA), by examining results of radiographic evaluations and identifying any trends in percentages of dogs classified as having desirable hip joint phenotypes. Study Design— Retrospective cohort study. Sample Population— OFA radiographic classifications (n=431,483) on dogs whelped between 1989 and 2003. Methods— Numbers and percentages of dogs classified by hip joint phenotypes were determined for 2-year cohorts. Differences between breeds and sexes were assessed using the Fisher's exact test, and odds ratios with 95% confidence intervals were calculated to express associations. The Cochran–Armitage test for trend was calculated to identify significant trends over time. Results— There were statistically significant (P<.05) increases in the proportion of all breeds of dogs evaluated as excellent and good from 1993 to 2003, controlling for gender and age at evaluation. Labrador Retrievers, Bernese Mountain Dogs, and Rottweilers had the highest proportions of excellent and good scores, and the highest rates of improvement in excellent and good scores were seen in Bernese Mountain Dogs and Rottweilers. Conclusions— Results support the contention that there have been improvements in hip joint phenotype classifications in dogs in the United States since the previous study (1989–1992), through increases in the proportion of dogs receiving excellent and good classifications. Clinical Relevance— Hip joint phenotype classifications can be used by dog breeders to develop breeding programs to improve the hip joints of future generations of dogs.
Behavioral Variability of Choices Versus Structural Inconsistency of Preferences

Theories of rational choice often make the structural consistency assumption that every decision maker's binary strict preference among choice alternatives forms a strict weak order. Likewise, the very concept of a utility function over lotteries in normative, prescriptive, and descriptive theory is mathematically equivalent to strict weak order preferences over those lotteries, while intransitive heuristic models violate such weak orders. Using new quantitative interdisciplinary methodologies, we dissociate the variability of choices from the structural inconsistency of preferences. We show that laboratory choice behavior among stimuli of a classical "intransitivity" paradigm is, in fact, consistent with variable strict weak order preferences. We find that decision makers act in accordance with a restrictive mathematical model that, for the behavioral sciences, is extraordinarily parsimonious. Our findings suggest that the best place to invest future behavioral decision research is not in the development of new intransitive decision models but rather in the specification of parsimonious models consistent with strict weak order(s), as well as heuristics and other process models that explain why preferences appear to be weakly ordered.
A simple method of measuring thoracic aortic pulse wave velocity in children: methods and normal values.

Background The objective of this study was to define a simple method of measuring thoracic aortic pulse-wave velocity (PWV) using only an aortic length regression equation based on the subject's height and two pulsed Doppler recordings of the aorta. Methods The thoracic aortas of 80 subjects (age range, 0-20 years) were measured retrospectively by direct echocardiographic visualization. A simple linear regression equation for thoracic aortic length on the basis of height was derived. PWV was defined as the thoracic aortic length, derived from the subject's height, divided by pulse transit time. Pulse transit time was defined as the difference in the time of onset of two pulsed Doppler recordings placed at the level of the aortic valve leaflet tips and the diaphragm. Normative data were retrospectively defined in 206 children. Results Thoracic aortic length was linearly related to subject height by the equation thoracic aortic length (cm) = 1.7 cm + 0.1 (height [cm]) ( R 2 = 0.98, P Conclusion Thoracic aortic PWV can be simply calculated from a routine echocardiogram, it is constant throughout childhood, and it may improve the assessment of left ventricular load.
Internet Privacy Policies of the Largest International Companies

This article is a review of Internet privacy policies of the worldâ€™s largest companies. The report begins with a background on the right to privacy and privacy issues arising out of Internet usage. Attempts to regulate Internet privacy and self-regulatory effectiveness also are reviewed. The methodology for this study is to update and extend Internet privacy analysis by analyzing Web sites of the largest international companies (Forbes International 100) for inclusion of fair information practices. In addition, a collection of consumer-centered practices is defined and studied. The general finding is that within Forbes International 100, fair information practices and consumer-centered privacy policies are not being followed closely. It is also found that large U.S. firms are more likely to publish a privacy policy on their Web site. Finally, if a large international firm does publish a privacy policy on its Web site, the level of compliance with fair information practices and consumer-centered policies is not significantly different between U.S. and non-U.S. firms. Implications of the study for researchers and practitioners are reviewed.
Pivotal research in cardiovascular syndromes in the elderly

The PRICE-1 conference was designed to identify near term priorities for funding cardiovascular research in the elderly. Twenty topics were identified with either break throughs in fundamental mechanisms of aging with cardiovascular systems or with critical importaance to cardiovascular carve of the elderly. (c) 2000 by CVRR, Inc.
Highly Active Catalysts for the Ring-Opening Polymerization of Ethylene Oxide and Propylene Oxide Based on Products of Alkylaluminum Compounds with Bulky Tetraphenol Ligands

Mixtures of hindered (poly)phenols and alkylaluminum compounds have been evaluated as catalysts for the polymerization of ethylene oxide (EO) and propylene oxide (PO). Certain ligands bearing four phenol groups form particularly active catalysts when combined with triisobutylaluminum (2 equiv) and triethylamine (1 equiv) as initiator. Productivities of >100 g/mmol Al have been achieved in both EO and PO polymerizations by use of a dibenzothiophene-bridged tetraphenol. In general, catalyst activity increases with the increasing bulk of the substituents ortho to the phenol hydroxyl groups. Mechanistic investigations support a dinuclear insertion process. Chain transfer to alcohol (2-propanol or benzyl alcohol) has been demonstrated. Poly(propylene oxide) produced in this manner is atactic and highly regioirregular.
A critical evaluation of new plate theories applied to laminated composites

Abstract The plate theory recently developed by Levinson is extended to laminates. Closed-form solutions of this theory, as well as those of Reissner-Mindlin plate theory with appropriate shear correction, Seide's discrete-layer plate theory, and the higher-order theory of Lo et al. are all compared with Pagano's elasticity-theory solution for the cases of cylindrical bending of a single orthotropic layer and a symmetric cross-ply (0°/90°/0°) laminate consisting of three equal-thickness layers. Quantities compared are maximum plate deflection, bending stress distribution and transverse shear stress distribution.
Chemical and physical properties of foot-and-mouth disease virus: a comparison with Maus Elberfeld virus.

Abstract The chemical and physical properties of foot-and-mouth disease (FMD) and Maus Elberfeld (ME) viruses have been compared, and it is concluded that these viruses are structurally similar. Thus, the total FMD virion mass is ca. 8.3 × 106 daltons based on an RNA mass of 2.6 × 106 daltons. The FMD virus capsid protein, ca. 5.7 × 106 daltons, is predominantly comprised of 60 identical 85,500 dalton protein subunits, each unit containing three non-identical polypeptides, VP1–3. Two additional components are present at levels of 33/virion (VP4; 13,700) and 2/virion (VP0; 39,500). The reported molecular weight for the FMD-12 S virion subparticle (2.5 – 3.0 × 105 daltons) may indicate that it is a trimer of the 85,500 dalton protein subunit, and is centered about a three-fold axis of the icosahedral virus.
Novel 17-azolyl steroids, potent inhibitors of human cytochrome 17α-Hydroxylase-C17,20-lyase (P45017α) : Potential agents for the treatment of prostate cancer

A new synthetic route to a variety of novel delta 16-17-azolyl steroids is described: it involves the nucleophilic vinylic "addition-elimination" substitution reaction of 3 beta-acetoxy-17-chloro-16-formylandrosta-5,16-diene (2) and azolyl nucleophiles. Some of these novel delta 16-17-azolyl steroids, 6, 17, 19, and 27-29, prepared in good overall yields, are very potent inhibitors of human and rat testicular P450(17) alpha. They are shown to be noncompetitive and appear to be slow-binding inhibitors of human P450(17) alpha. The most potent compounds are 3 beta-hydroxy-17-(1H-imidazol-1-yl)androsta-5,16-diene (17), 3 beta-hydroxy-17-(1H-1,2,3-triazol-1-yl)androsta-5,-16-diene (19), and 17-(1H-imidazol-1-yl)androsta-4,16-dien-3-one (28), with Ki values of 1.2, 1.4, and 1.9 nM, respectively, being 20-32 times more potent than ketoconazole (Ki = 38 nM). Spectroscopic studies with a modified form of human P450(17) alpha indicate that the inhibition process involves binding of steroidal azole nitrogen to the heme iron of the enzyme. Furthermore, some of these potent P450(17) alpha inhibitors (27-29) are also powerful inhibitors of steroid 5 alpha-reductase, and others (17 and 19) appear to exhibit strong antiandrogenic activity in cultures of the LNCaP human prostatic cancer cell line. These novel compounds with impressive dual biological activities make them strong candidates for development as therapeutic agents for treatment of prostate cancer and other disease states which depend on androgens.
The Solar System Environment

The description of the planetary and interplanetary environments, presented in this paper, is based on the latest available experimental data, or otherwise typical, quantitative information, which can be used for preliminary estimates of a given mission requirement.