cssi/SciSciGPT-SciSciNet huggingface dataset:
Thyroid hormone and vitamin D metabolism in the rat

Abstract The effect of induced hypothyroidism on vitamin D metabolism, intestinal calcium transport, and plasma levels of calcium and phosphorus by feeding an antithyroid drug, propylthiouracil, has been studied in rats. Hypothyroidism is associated with depressed growth and diminished circulating levels of calcium, phosphorus, and 1,25-dihydroxyvitamin D 3 . In contrast, plasma levels of 25-hydroxyvitamin D 3 and 24R,25-dihydroxyvitamin D 3 are unchanged by the hypothyroidism. The administration of thyroid hormone to hypophysectomized rats assumed to be hypothyroid increases plasma 1,25-dihydroxyvitamin D 3 suggesting that this effect of the thyroid hormone is indpendent of the pituitary. Intestinal calcium transport is increased by hypothyroidism in spite of low circulating levels of 1,25-dihydroxyvitamin D 3 . Since hypophysectomy also diminishes plasma 1,25-dihydroxyvitamin D and phosphorus levels but does not cause an increase in intestinal calcium transport, it is suggested that hypophosphatemic stimulation of intestinal calcium transport is mediated by a hypophyseal factor indpendent of vitamin D. However, the lowered plasma levels of calcium and phosphorus found in hypothyroidism may in part result from reduction in circulating 1,25-dihydroxyvitamin D 3 levels. The data also support the earlier observations that modulation of intestinal calcium transport by phosphorus is not entirely mediated by vitamin D.
The effects of ketone bodies, bicarbonate, and calcium on hepatic mitochondrial ketogenesis.

Abstract The effect of various factors on hepatic mitochondrial ketogenesis was investigated in the rat. A comparison of three different incubation media revealed that bicarbonate ion inhibited the rate of ketone body production and decreased the ratio of 3-hydroxybutyrate/acetoacetate. The addition of 0.8 m m calcium caused significant inhibition of ketogenesis from both octanoate (40–50%) and palmitate (25–30%) and no change in the ratio of 3-hydroxybutyrate/acetoacetate. In the presence of components of the malate/aspartate shuttle, the inhibition by calcium was 80% or more with both substrates. Experimental alteration of the respiratory state of the mitochondria from state 3 to state 4 was associated with an enhanced rate of ketogenesis. The addition of ketone bodies themselves had marked effects on the rate of ketone body production. Increasing amounts of exogenously added acetoacetate were accompanied by increasing rates of total ketone body production reflecting enhanced 3-hydroxybutyrate synthesis. In the presence of added 3-hydroxybutyrate, there was striking inhibition of ketogenesis. Rotenone, which prevents oxidation of NADH 2 via the electron transport chain, almost completely inhibited ketone body synthesis. This inhibition was partially overcome by the addition of acetoacetate which regenerates NAD + from NADH 2 during conversion to 3-hydroxybutyrate. These observations provide evidence for additional sites of metabolic control over hepatic ketogenesis.
THE INFLUENCE OF ORAL RECALL ON IMMEDIATE AND DELAYED MEMORY FOR MEANINGFUL MATERIAL PRACTICED UNDER DELAYED AUDITORY FEEDBACK.

Summary Three groups of Ss read a five-paragraph story. One group read the middle paragraph under conditions of .2-second DAF. The other two groups functioned as control groups. Both an immediate and a delayed oral recall were obtained. The usual changes in reading rate were observed. Immediate memory for the material presented under DAF was severely impaired. Delayed retention showed a marked relative increase, but not enough of an absolute increase to eliminate the significant difference between the experimental and the control groups.
Measuring 'no-win' waterscapes: Experience-based scales and classification approaches to assess household water security in colonias on the US-Mexico border

Abstract This paper develops a household water security measurement for low-income peri-urban and rural communities (“colonias”) on the US–Mexico border. The complexity of a “no-win” waterscape – where water service exists but is relatively expensive and water quality is still precarious – precludes a meaningful assessment and analysis because there are no existing measurement tools to capture water insecurity at the household level. Informed by critical environmental epistemology, the paper incorporates perspectives from colonias residents through qualitative research and survey development. The study advances previous work on water security by developing a cumulative scale for each characteristic of household water security then clusters households into water security classes using a non-parametric statistical procedure. The analysis identified four water security classes: (1) Water Secure; (2) Marginally Water Secure; (3) Marginally Water Insecure; (4) Water Insecure. While all households in the survey are connected to water service, only 45% are broadly “water secure” while 55% are “water insecure.” Statistical analysis confirmed the robustness of the scaling and clustering procedure, thus, providing evidence to describe household water insecurity in “no-win” waterscapes.
Cytomegalovirus as a Primary Pulmonary Pathogen in AIDS

In patients with AIDS, isolation of cytomegalovirus (CMV) from respiratory secretions is common. It is often found with other pathogens, which has led to debate regarding its role as a primary pulmonary pathogen. A retrospective investigation of patients with AIDS and CMV as a sole pulmonary isolate was performed in an attempt to describe their clinical presentation and course. All patients admitted to the hospital with pneumonia and with BAL or transbronchial biopsy (TBB) specimen positive for CMV between 1991 and 1994 were identified through a review of inpatient records. Inclusion criteria included positive CMV cultures from BAL, cytomegalic inclusion bodies from BAL or TBB, and thorough documentation of the absence of other pulmonary pathogens. Nine patients met the inclusion criteria for CMV pneumonitis. Seven were male and two were female, ages 26 to 44 years, and all had a history of opportunistic infections. Typical clinical presentation was characterized by increased respiratory rate, hypoxemia, and diffuse interstitial infiltrates. The mean CD4 count was 29.6 (±22) cells per cubic millimeter, mean lactate dehydrogenase level was 414 (±301) IU/L, and in seven patients in whom CMV antigen was measured it was greater than 50 positive cells per 200,000 WBCs. Three untreated patients died of respiratory failure and three had autopsy confirmation of CMV pneumonia. Five patients were treated with anti-CMV therapy for at least 2 weeks, and all demonstrated improvement in symptoms, oxygen saturation, and chest radiograph. At 3 months follow-up, all five patients were asymptomatic with no pulmonary symptoms. At 6 months follow-up, three of the five patients remained asymptomatic; the other two died of other opportunistic infections. In at least these nine patients, CMV represented a primary pulmonary pathogen. Patients who were treated responded quickly and were able to be discharged home from the hospital with marked improvement in their symptoms. We recommend that clinicians consider this diagnosis in the proper setting and consider treatment with anti-CMV therapy.
Mesoporous and Mesostructured Materials for Optical Applications

Mesostructured and mesoporous materials are emerging as a new class of optical materials. For mesostructured materials (inorganic/surfactant composites), prepared using a one-step synthesis procedure where the inorganic/surfactant/optically active species coassemble, the unique architecture provided by the surfactant-inorganic phase separation allows for higher concentrations compared to traditional sol-gel glasses and protective packaging of uniform three-dimensional arrays of optical species. The corresponding regularly arranged pores found in mesoporous materials (inorganic only) provide a high surface area to better disperse optically active components and allow for rapid diffusion for optical sensor applications. In this review, we discuss recent research results on the techniques used to produce optically functionalized mesostructured and mesoporous materials and the characterization of the final composites.
Inhibition of aggressiveness by ovarian hormones.

ACONSIDERABLE body of experimental and observational evidence indicates that the social behavior of animals is influenced by gonadal hormones (Beach, 1948). In many species androgen is associated with aggressive activity (Collias, 1944). Testicular hormone has been found to increase the incidence of fighting behavior in male reptiles (Evans, 1946; Noble and Greenberg, 1941), birds (Davis and Domm, 1941; Emlen and Lorenz, 1942) and mammals (Beeman, 1947). Androgen also stimulates aggressiveness in the females of some mammalian species (Huffman, 1941). Some animals establish and maintain stable social orders which are characterized by differential dominance status for each invididual, and the administration of androgenic hormones tends to increase the dominance ranking of treated individuals although species differences in this respect are marked (Birch and Clark, 1950; Mirsky, in press). In contrast to androgen, estrogen has been regarded as an inhibitor of aggressive behavior although this is not true in ...
Micro-displacement Fiber Sensor Using Two-frequency Interferometry

A He-Ne Zeeman laser has been utilized as a two-frequency light source in a Michelson-type micro-displacement fiber sensor. A polarization maintaining fiber has been installed in the sensing arm, which facilitates flexibility and allows the sensing region to be remotely located. This fiber sensing arm is arranged to replace a quarterwave plate component. The fiber sensor system has a resolution of half a micrometer.
Unusual Tumors of the Thyroid Gland

Thyroid neoplasms are classified into three major categories: epithelial, nonepithelial, and secondary. Most primary epithelial tumors of thyroid are derived from follicular cells. These include follicular adenoma and carcinoma (Hurthle and non-Hurthle), and papillary carcinoma and its variants. Other primary epithelial tumors include medullary carcinoma, mixed medullary and follicular carcinomas, insular and poorly differentiated carcinoma, anaplastic carcinoma, and the least common squamous carcinoma and related tumors. The nonepithelial tumors are rare; the most common include malignant lymphoma and tumors arising from the mesenchymal elements. The secondary tumors represent metastatic tumors to the thyroid usually originating in lung, kidney, and breast. In this article, the authors review the unusual tumors of the thyroid, their morphologic features, and clinical and prognostic implications.
NEIGHBORING GROUP EFFECTS IN THE REGIOSELECTIVE CYCLIZATION OF VICINAL TRANS-1,2-BROMOHYDRINS TO EPOXIDES

Abstract Bromocyclopentitols and amino (or amido) bromocyclopentitols having a CBr bond trans to two different vicinal hydroxyl groups show selectivity in base-promoted epoxide formation. The role of adjacent polar substituents in directing bromohydrin cyclization is discussed.
A Free Terminal Ileal Perforation From Active Crohn Disease in Pregnancy: A Diagnostic Challenge

The surgical management of the complications of Crohn disease is often challenging. These difficulties are compounded in pregnancy by competing interests of the mother and the baby. In this report, we describe the presentation and surgical management of a patient in her second trimester with active Crohn disease who required emergent surgical intervention. She had presented with the uncommon complication of a free perforation in the presence of active untreated disease.
NMR studies of mercurial-halogen equilibria

Abstract 35Cl and 81Br NMR relaxation time measurements are used to determine the equilibrium positions in reactions of the form RSHgX + Y = RSHgY + X where X is chloride or bromide, and Y is hydroxide ion, histidine, thiosulfate and sulfite. The data require that for the association of RS− ion with Hg2+ ion, the ratio K 1 K 2 is between 2 × 104 and 102.
A COMPARISON OF TUMOUR INCIDENCE ANALYSES APPLICABLE IN SINGLE-SACRIFICE ANIMAL EXPERIMENTS

Monte Carlo methods are used to evaluate the operating characteristics of several trend tests for comparing incidence rates of occult tumours. The candidate tests are applicable in long-term animal experiments that have just one sacrifice time and no information on cause of death. When survival decreases with dose and the tumour is lethal, the tests that do not adjust for survival or that assume tumours are non-lethal behave conservatively, whereas the test that assumes tumours are rapidly lethal rejects the hypothesis of equal incidence rates too frequently. The only test which consistently operates at the correct level is one that specifies a constant difference between the death rates for animals with and without the tumour. Surprisingly, the test that specifies a constant ratio of these death rates often is conservative. Finally, a test based on a simple modification of the unadjusted test, which accounts for differential mortality by scaling down the size of the risk set, performs reasonably well in many cases. Among the tests that operate at the proper level, the constant risk difference test consistently exhibits high power across a wide range of situations.
Dynamics of energy transfer and soft-landing in collisions of protonated dialanine with perfluorinated self-assembled monolayer surfaces

Chemical dynamics simulations are reported which provide atomistic details of collisions of protonated dialanine, ala2-H(+), with a perfluorinated octanethiolate self-assembled monolayer (F-SAM) surface. The simulations are performed at collision energies Ei of 5.0, 13.5, 22.5, 30.00, and 70 eV, and incident angles 0° (normal) and 45° (grazing). Excellent agreement with experiment (J. Am. Chem. Soc., 2000, 122, 9703-9714) is found for both the average fraction and distribution of the collision energy transferred to the ala2-H(+) internal degrees of freedom. The dominant pathway for this energy transfer is to ala2-H(+) vibration, but for Ei = 5.0 eV ∼20% of the energy transfer is to ala2-H(+) rotation. Energy transfer to ala2-H(+) rotation decreases with increase in Ei and becomes negligible at high Ei. Three types of collisions are observed in the simulations: i.e. those for which ala2-H(+) (1) directly scatters off the F-SAM surface; (2) sticks/physisorbs on/in the surface, but desorbs within the 10 ps numerical integration of the simulations; and (3) remains trapped (i.e. soft-landed) on/in the surface when the simulations are terminated. Penetration of the F-SAM by ala2-H(+) is important for the latter two types of events. The trapped trajectories are expected to have relatively long residence times on the surface, since a previous molecular dynamics simulation (J. Phys. Chem. B, 2014, 118, 5577-5588) shows that thermally accommodated ala2-H(+) ions have an binding energy with the F-SAM surface of at least ∼15 kcal mol(-1).
EVALUATION OF THREE OIL SPILL LABORATORY DISPERSANT EFFECTIVENESS TESTS

ABSTRACT Chemical dispersants can be used to reduce the interfacial tension of floating oil slicks so that the oils disperse more rapidly into the water column and thus pose less of a threat to sho...
Spinal cord dose is higher than expected in head and neck radiation.

Abstract Myelopathy is a feared consequence of radiation therapy. Risk factors are multifocal; therefore, total dose calculation is crucial. We evaluated the contribution of scatter radiation to obtain an accurate cumulative spinal cord dose. Twenty patients undergoing three field head and neck radiation by Cobalt or 6 MV Linac had a total cord dose calculated from direct and scatter radiation. The cord was removed from the radiation field at tumor doses no higher than 4,400 cGy. Total tumor dose ranged from 5,400–7,400 cGy (mean 6060). All patients achieved the prescribed dose and none were lost to follow up (mean 36 months). It was found that scatter radiation can contribute as much as 20% extra dose to the spinal cord. Mean extra dose was 9% (range 1%–20%). This additional dose ranged from 52–810 cGy (mean 339 cGy). No apparent difference was seen with Cobalt or Linac source. Our conclusion was that significant additional dose is delivered to the spinal cord by scatter radiation and that scatter may contribute more to the development of myelopathy than previously believed.
Role of arginine vasopressin and corticotropin-releasing factor in mediating alcohol-induced adrenocorticotropin and vasopressin secretion in male rats bearing lesions of the paraventricular nuclei

In male rats, lesions of the paraventricular nucleus (PVN) of the hypothalamus attenuate, but do not abolish, adrenocorticotropin (ACTH) secretion in response to acute alcohol injection. As the PVN is the major source of corticotropin-releasing factor (CRF) in the median eminence, this observation suggests that extra-PVN brain regions, and/or ACTH secretagogues other than CRF (e.g. arginine vasopressin (AVP)), mediate ACTH stimulation by alcohol. This hypothesis was tested by examining the effect of AVP immunoneutralization in PVN-lesioned (PVNx) rats. Removal of endogenous AVP diminished alcohol-evoked ACTH secretion in both sham-operated and PVNx animals, indicating that AVP from outside the PVN partially mediates the hypothalamic-pituitary-adrenal (HPA) axis response to alcohol. This led us to determine whether alcohol might also regulate AVP steady-state gene expression in the supraoptic nucleus (SON) and PVN, and/or CRF mRNA in the PVN and the central nucleus of the amygdala (AMY). In the magnocellular portion of the PVN, sham-operated animals showed significantly increased PVN levels of both CRF and AVP mRNAs 3 h after alcohol. In the SON, alcohol administration tended to decrease AVP gene expression in PVNx rats, while the drug increased AVP mRNA levels in the SON of sham-operated rats. AMY levels of CRF mRNA were unaffected by these manipulations. Finally, since the regulation of alcohol-induced AVP mRNA levels in the SON appeared to depend on the presence of the PVN, we measured peripheral levels of AVP in both sham-operated and PVNx animals after injection of vehicle or alcohol. Although AVP decreased in all groups, alcohol depressed AVP secretion to a greater extent in PVNx animals, suggesting that AVP systems are more sensitive to inhibition in the absence of the PVN. Our results demonstrate that although AVP of PVN origin may participate in regulating the stimulatory effect to AVP on ACTH secretion, AVP from areas other than the PVN also plays a role. Additionally, regulation of both AVP gene expression in the SON and secretion in the systemic circulation are altered in rats bearing lesions of the PVN.
Ab Initio Nonadiabatic Molecular Dynamics of the Ultrafast Electron Injection across the Alizarin−TiO2 Interface

The observed 6-fs photoinduced electron transfer (ET) from the alizarin chromophore into the TiO2 surface is investigated by ab initio nonadiabatic (NA) molecular dynamics in real time and at the atomistic level of detail. The system derives from the dye-sensitized semiconductor Gratzel cell and addresses the problems of an organic/inorganic interface that are commonly encountered in photovoltaics, photochemistry, and molecular electronics. In contrast to the typical Gratzel cell systems, where molecular donors are in resonance with a high density of semiconductor acceptor states, TiO2 sensitized with alizarin presents a novel case in which the molecular photoexcited state is at the edge of the conduction band (CB). The high level ab initio analysis of the optical absorption spectrum supports this observation. Thermal fluctuations of atomic coordinates are particularly important both in generating a nonuniform distribution of photoexcited states and in driving the ET process. The NA simulation resolves th...
The rostral projections of the primate vestibular nuclei: an experimental study in macaque, baboon and chimpanzee.

The ascending projections of the vestibular nuclei were studied with the selective silver methods of Nauta-Gygax (Nauta,'57), Voneida ('67) and Fink et al. ('67) in macaque, baboon and chimpanzee. Degenerated axons pass from lesions in the vestibular nuclei into the medial medullary and pontine tegmentum bilaterally, the abducens nuclei, the contralateral vestibular complex and in the medial longitudinal fasciculus to the nuclei of the III and IV nerves. A few fibers pass rostral to the oculomotor complex into the interstitial nuclei of Cajal, the nuclei of Darkshewitsch and the nuclei of the posterior commissure. No degenerated fibers originating in vestibular nuclear lesions were observed to ascend rostral to the level of the posterior commissure. Degenerated fibers rostral to this level could be traced, in sagittal, horizontal and frontal sections, to incidental damage to the superior cerebellar peduncle and the posterior column nuclei. Damage to the acoustic striae produced ascending degeneration in the auditory system, but this did not pass rostral to the inferior colliculus. The incidentally damaged tracts could be seen, in sections in three planes, to be separate in their course and terminations from the fibers ascending from the vestibular nuclei in the medial longitudinal fasciculus. The experimental evidence lends no support to the supposition that direct secondary vestibular connections to the diencephalon exist. Previous anatomical descriptions of direct vestibulothalamic connections appear to result from failure to discriminate between fibers originating in the vestibular nuclei and fibers arising in adjacent regions. Vestibular impulses reaching the diencephalon must pass over third or higher order neurons after synapse at lower levels.
Nanoscale plasmonics for molecular recognition and light-triggered molecular release

Metallic nanostructures designed to provide plasmon resonances at specific optical frequencies and strong yet uniform near-field electromagnetic enhancements are useful nanodevices for light-driven sensing and actuation. The large local fields on the surface of these structures support surface-enhanced spectroscopies such as surface enhanced Raman spectroscopy (SERS). To use plasmonic nanostructures for molecular recognition, their properties must be exploited in combination with molecular layers that provide an optical signature that corresponds to capture of a target molecule. DNA oligomers bound to the surface of plasmonic nanostructures provide an optical signal that is sensitive to the conformational changes in the DNA itself due to interaction with other molecules, as would occur in binding events. This type of optical detection is label-free and reporter-free, that is, it does not depend upon the presence of a dye molecule bound to the DNA to provide an optical signal. DNA-drug interactions can be directly detected in this manner: the binding kinetics of chemotherapy drugs such as cisplatin can be directly monitored by this method, providing a streamlined spectroscopic approach to drug discovery.
Performance driven placement for cell-based designs

In this paper we present a performance driven quadratic programming based placement method for large ASICs. A set of performance bounds is first calculated for a given circuit. The performance bounds are calculated using a zero-slack algorithm. The performance bounds are then used to derive a timing driven placement for cell based layouts. The bounds, if satisfied, guarantee correct operation of circuit for specified timing requirements. The approach has been integrated with high-level synthesis tools for generating layouts of datapaths of synthesized designs.
Potential for crime and knowledge of legal sanctions

The importance of knowledge of legal sanctions for deterrence is debatable, but the debate can be resolved only through exploratory research on the subject Using survey data, this research compares individuals in terms of the degree to which they accurately perceive statutory maximum prison sentences for 19 types of crimes. Contrary to expectations, evidence that high‐potential offenders perceived statutory maximums significantly more accurately than low‐potential offenders is rather limited, with most respondents unaware of maximum prison sentences. The empirical results also show that respondents apparently derive their perceptual estimates of the maximums from shared beliefs about what ought to be done to criminal offenders, not knowledge of what actually can be done to them, as indicated by the significant relationships between individual perceptions of maximum prison sentences and individual preferences for those sentences. The implications of those findings for developing and testing a theory of det...
Correction for Systematic Wavelength Shifts in Atomic Beam Devices

Light emitted or absorbed by atoms in an atomic beam is shifted in frequency relative to the frequency for a stationary atom if the light ray is not normal to the trajectory of the atom. The magnitude of this shift is calculated and several devices which correct for this effect are described. For photoelectric recording of interference fringes, complete compensation can be achieved. In the case of photographic recording, it is shown that the residual error is negligible.
DNA changes during sequential leaf senescence of tobacco (Nicotiana tabacum)

Age related DNA changes in tobacco (Nicotiana tabacum) leaf nuclei were investigated by Feulgen cytophotometry, thermal denaturation, renaturation, and DNA-DNA hybridization studies during sequential leaf senescence. Cytophotometric Feulgen-DNA comparison measurements between young and senescing nuclei displayed 18% reduction in Feulgen-DNA values, with a corresponding decrease in nuclear area in senescing nuclei. Hydrolysis kinetics indicated that the loss was not due to compactness of the DNA as the curves for older nuclei were consistently lower than curves generated from younger nuclei. DNA loss in senescing nuclei was associated with a decrease in euchromatin or shift from euchromatin to facultative heterochromatin. Purified DNA from young and senescing leaf nuclei did not display different thermal profiles nor did hydroxylapatite chromatography reassociation curves. DNA-DNA hybridization in free solution from young and senescing leaf DNA performed by a Gilford thermo-programmer system indicated that DNA of senescing tobacco nuclei reassociated more slowly than DNA from young nuclei and the mixture of young and senescing leaf DNA displayed intermediate reassociation values. The study indicates that the DNA changes during senescence involve a complex phenomenon which includes the possibility of small single strand nicks undetectable by thermal denaturation, and a loss of small double strand fragments which were detectable only by precise DNA-DNA free solution reassociation and not by hydroxylapatite chromatography reassociation.
Broadcast Authentication With Preferred Verifiers

We introduce a novel cryptographic paradigm of broadcast authentication with “preferred” verifiers (BAP). With BAP, the message source explicitly targets a set of one or more verifiers. For an attacker, forging authentication data of a source, for purposes of fooling preferred verifiers may be substantially more difficult than fooling other (non-preferred) verifiers. We investigate broadcast authentication (BA) with hashed random pre-loaded subsets (HARPS), which caters for such a distinction. HARPS, provides for efficient broadcast authentication, with and without preferred verifiers. We argue that BA using HARPS has some very desirable features that make it well suited for securing ad hoc routing protocols. We also briefly discuss some applications of the novel paradigm of BAP in the context of ad hoc routing protocols.
The Motion of Microbubbles in a Forced Isotropic and Homogeneous Turbulence

We have studied the concentration distribution of microbubbles in forced isotropic turbulence. An initially uniform concentration field is shown to evolve to a highlyintermittent orspotty concentration distribution at long time due to the interactions of microbubbles with small-scale, intense, and coherent flow vortical structures. The maximum bubble concentration can be as large as 3,000 times the mean concentration and the local accumulations occur preferentially in the regions of high flow vorticity and low flow pressure. A quantitative measure of global nonuniformity in the concentration field is used to confirm that the preferential accumulation does follow Kolmogorov scaling, as opposed to the large-scale scaling commonly used for dispersion quantification.
Mobile news use and participation in elections: A bridge for the democratic divide?:

This study explores the role of mobile news in democracy by examining individual-level variations in mobile election news use based on demographics, socioeconomic indicators, and mobile media activ...
On an approximate subspace method for eigenfilter computation

A method has been proposed for estimating the frequencies of sinusoids in additive white Gaussian noise. The method is an approximation to Kumaresan's "improved Pisarenko" method, which can be thought of as the computation of an FIR notch filter with zeros at the signal frequencies. The new algorithm consists of subtracting a small e from the
A Comparative Analysis of Studies on Heat Transfer and Fluid Flow in Microchannels

The extremely high rates of heat transfer obtained by employing microchannels makes them an attractive alternative to conventional methods of heat dissipation, especially in applications related to the cooling of microelectronics. A compilation and analysis of the results from investigations on fluid flow and heat transfer in micro- and mini-channels and microtubes in the literature is presented in this review, with a special emphasis on quantitative experimental results and theoretical predictions. Anomalies and deviations from the behavior expected for conventional channels, both in terms of the frictional and heat transfer characteristics, are discussed.
Freeform fabricated scaffolds with roughened struts that enhance both stem cell proliferation and differentiation by controlling cell shape

We demonstrate that freeform fabricated (FFF) scaffolds with a roughened surface topography can support hBMSC proliferation, while also inducing osteogenic differentiation, for maximized generation of calcified, bone-like tissue. Previously, hBMSCs rapidly proliferated, without osteogenic differentiation, during culture in FFF scaffolds. In contrast, hBMSCs underwent osteogenic differentiation, with slow proliferation, during culture in nanofiber scaffolds. Analysis of cell morphology showed that the topography presented by the nanofiber scaffolds drove hBMSC differentiation by guiding them into a morphology that induced osteogenic differentiation. Herein, we hypothesized that using the high-surface area architecture of FFF scaffolds to present a surface roughness that drives hBMSCs into a morphology that induces osteogenic differentiation would yield a maximum amount differentiated hBMSCs and bone-like tissue. Thus, a solvent etching method was developed that imparted a 5-fold increase in roughness to the surface of the struts of poly(e-caprolactone) (PCL) FFF scaffolds. The etched scaffolds induced osteogenic differentiation of the hBMSCs while un-etched scaffolds did not. The etched scaffolds also supported the same high levels of hBMSC proliferation that un-etched scaffolds supported. Finally, hBMSCs on un-etched scaffolds had a large spread area, while hBMSCs on etched scaffolds has a smaller area and were more rounded, indicating that the surface roughness from the etched scaffolds dictated the morphology of the hBMSCs. The results demonstrate that FFF scaffolds with surface roughness can support hBMSC proliferation, while also inducing osteogenic differentiation, to maximize generation of calcified tissue. This work validates a rational approach to scaffold fabrication where the structure of the scaffold was designed to optimize stem cell function by controlling cell morphology.
Insulin-Mediated Venodilation Is Impaired in Patients With High Cholesterol

Recently we have reported that insulin attenuates norepinephrine (NE)-induced vasoconstriction via a cyclic GMP-NO synthase pathway. Because hypercholesterolemia has been associated with abnormal endothelial function, we investigated whether insulin-mediated vasodilation is impaired in hypercholesterolemia. To assess vasoreactivity, NE (12.5, 25, 50, and 100 ng/min), NE (100 ng/min) combined with insulin (8, 16, 24, and 32 microU/min), and NE (100 ng/min) combined with sodium nitroprusside (0.01, 0.1, 1, 10, and 100 ng/min) were infused into dorsal hand veins. Changes in venous diameter were measured by ultrasonography, using a 7.5-MHz transducer. Twenty-two healthy, normotensive hypercholesterolemic subjects (HC; mean total cholesterol 6.93 mmol/L, HDL 1.45 mmol/L, LDL 4.81 mmol/L) and 18 age-matched normal control subjects (NC; mean total cholesterol 4.81 mmol/L, HDL 1.16 mmol/L, LDL 3.18 mmol/L) were studied. All HC had normal glucose tolerance test results. Baseline vein diameters were similar between groups, and the vasoconstrictor response to NE was not significantly different between HC and NC. Insulin significantly attenuated NE-induced vasoconstriction in NC but not in HC (P<0.01). Both groups were able to venodilate with sodium nitroprusside. To investigate the effects of cholesterol reduction on vascular reactivity, venoreactivity studies were repeated in 12 HC after treatment with 20 to 40 mg/d lovastatin for 6 weeks. There were no significant venoreactivity changes with the treatment. Plasma LDL cholesterol concentration was inversely correlated to venodilator effect of insulin (r=-0.42, P<0.02). In conclusion, insulin-mediated vasodilation is impaired in patients with high cholesterol. Absence of normal insulin-mediated but not sodium nitroprusside-induced venodilation in hypercholesterolemia suggests that insulin-mediated vasodilation is endothelium dependent.
Effects of endotracheally administered distilled water and normal saline on the arterial blood gases of dogs.

The effects of endotracheally (ET) administered distilled water (DW) and normal saline solution (NSS) on the arterial blood gases of dogs were compared. When distilled water was administered endotracheally, arterial pH was depressed to 99.36% of baseline values within 5 minutes. When compared to pH changes following ET administration of NSS the depression of pH following DW administration was significant (P 2 was depressed to 61% of baseline values and remained significantly depressed throughout the experiment. In comparison, following ET NSS administration, PO 2 was depressed substantially less, and remained at significantly higher levels for the entire experiment. In dogs, administration of NSS by the ET route produces less detrimental effects on arterial blood gases than does the ET administration of DW. This may have implications for the choice of diluent for human drug administration using the ET route.
Characterization of near- and far-field radiation from ultrafast electronic systems

Accurate and computationally efficient characterization of near- and far-field radiation from a class of microwave, millimeter wave, and ultrafast systems is presented. A numerical technique is utilized which combines the finite-difference time domain method with a spatial transformation, the Kirchhoff surface integral. Included in the analysis are inhomogeneous material parameters, small feature size relative to wavelengths of interest, and the wide-band nature of the radiation. Based on simulation results, a simple model of the radiation from an inhomogeneous structure is developed. Finally, the technique is applied to accurately characterize the radiation from a photoconducting structure.
Angle-resolved low coherence interferometry for detection of dysplasia in Barrett's esophagus.

Barrett’s esophagus (BE) is a metaplastic change of the esophagus which is associated with an increased risk of esophageal adenocarcinoma (EAC)1. The incidence of this cancer has risen dramatically in the U.S. in the last 40 years,2 and prognosis for subjects presenting with symptomatic EAC is dismal, with less than a 15% 5-year survival.3 For this reason, strategies aimed at prevention figure prominently in societal guidelines for the care of BE.4
Evaluation of Boundary Layer Depth Estimates at Summit Station, Greenland

AbstractBoundary layer conditions in polar regions have been shown to have a significant impact on the levels of trace gases in the lower atmosphere. The ability to properly describe boundary layer characteristics (e.g., stability, depth, and variations on diurnal and seasonal scales) is essential to understanding the processes that control chemical budgets and surface fluxes in these regions. Surface turbulence data measured from 3D sonic anemometers on an 8-m tower at Summit Station, Greenland, were used for estimating boundary layer depths (BLD) in stable to weakly stable conditions. The turbulence-derived BLD estimates were evaluated for June 2010 using direct BLD measurements from an acoustic sounder located approximately 50 m away from the tower. BLDs during this period varied diurnally; minimum values were less than 10 m, and maximum values were greater than 150 m. BLD estimates provided a better comparison with sodar observations during stable conditions. Ozone and nitrogen oxides were also measur...
First versus second portion of expired air and duration of breath holding in the sampling of expired air carbon monoxide

Summary Two experiments evaluated the importance of obtaining air samples from lower in the respiratory system in order to detect smokers. The first experiment with 102 adults indicated that end-expired air samples were significantly higher in CO level than samples of the first portion of expired air. However, the ability to predict smokers from the two samples did not differ. Correlations between smoking measures and levels of CO from the two samples were virtually identical. Elimination of high-rate smokers resulted in equivalent correlational and predictive outcomes. The second experiment was conducted with 104 adolescents. There was no difference in the detection of smoking using first versus second portion samples. Duration of breath holding was also examined as an independent variable. CO levels after 20 s of breath holding were significantly higher than those after 15 s. However accuracy in detecting smokers was not significantly affected by the duration of breath holding. Detection of smokers may not be improved through the use of more stringent sampling procedures and may prove unnecessary in research which uses CO to corroborate self-report.
Holographic elements for modulation transfer function testing of detector arrays

A holographic technique is presented that increases the flux-transfer efficiency of laser speckle generation by a factor of 100 over the integrating sphere method. This makes a wider range of low-power lasers usable for the speckle MTF test method, and increases the number of wavelengths at which the test can be applied.
Within-stem variation of respiration in Pseudotsuga menziesii (Douglas-fir) trees

Summary • A technique for measuring in vitro respiration was investigated to understand why rates were higher than those reported in vivo and to elucidate trends within mature Pseudotsuga menziesii (Douglas-fir) trees. • Extracted increment cores were divided into 3–4 radial depths and a gas chromatograph was used to compare respiration rates radially and vertically within stems. • Respiration of inner bark was 2–3 times greater than sapwood, and 50–70% higher in outer than inner sapwood. Inner bark and outer sapwood released > 40% more CO2 at treetops than at bases. Trends were robust for CO2 production on a core dry-mass, volume, or total carbon basis. By contrast, CO2 production on a nitrogen basis showed almost no significant variation. • This in vitro technique provided an effective index for relative differences in respiration within tree stems. Discrepancies between in vitro and in vivo measurements might be related to the gaseous environment in stems. The estimated within-stem gradients in respiration were possibly determined by enzyme quantity and availability and could be useful in scaling to whole-trees.
Detecting and tolerating byzantine faults in database systems

This thesis describes the design, implementation, and evaluation of a replication scheme to handle Byzantine faults in transaction processing database systems. The scheme compares answers from queries and updates on multiple replicas which are off-the-shelf database systems, to provide a single database that is Byzantine fault tolerant. The scheme works when the replicas are homogeneous, but it also allows heterogeneous replication in which replicas come from different vendors. Heterogeneous replicas reduce the impact of bugs and security compromises because they are implemented independently and are thus less likely to suffer correlated failures. A final component of the scheme is a repair mechanism that can correct the state of a faulty replica, ensuring the longevity of the scheme. The main challenge in designing a replication scheme for transaction processing systems is ensuring that the replicas state does not diverge while allowing a high degree of concurrency. We have developed two novel concurrency control protocols, commit barrier scheduling (CBS) and snapshot epoch scheduling (SES) that provide strong consistency and good performance. The two protocols provide different types of consistency: CBS provides single-copy serializability and SES provides single-copy snapshot isolation. We have implemented both protocols in the context of a replicated SQL database. Our implementation has been tested with production versions of several commercial and open source databases as replicas. Our experiments show a configuration that can tolerate one faulty replica has only a modest performance overhead (about 10-20% for the TPC-C benchmark). Our implementation successfully masks several Byzantine faults observed in practice and we have used it to find a new bug in MySQL. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)
A Theory Of Frequency Domain Invariants: Spherical Harmonic Identities for BRDF/Lighting Transfer and Image Consistency

This paper develops a theory of frequency domain invariants in computer vision. We derive novel identities using spherical harmonics, which are the angular frequency domain analog to common spatial domain invariants such as reflectance ratios. These invariants are derived from the spherical harmonic convolution framework for reflection from a curved surface. Our identities apply in a number of canonical cases, including single and multiple images of objects under the same and different lighting conditions. One important case we consider is two different glossy objects in two different lighting environments. For this case, we derive a novel identity, independent of the specific lighting configurations or BRDFs, that allows us to directly estimate the fourth image if the other three are available. The identity can also be used as an invariant to detect tampering in the images. Although this paper is primarily theoretical, it has the potential to lay the mathematical foundations for two important practical applications. First, we can develop more general algorithms for inverse rendering problems, which can directly relight and change material properties by transferring the BRDF or lighting from another object or illumination. Second, we can check the consistency of an image to detect tampering or image splicing.
Trends in premarital sex in the United States 1954-2003.

SYNOPSIS Objectives. Policy and programmatic efforts promoting sexual abstinence until marriage have increased, but it is unclear whether establishing such behavior as normative is a realistic public health goal. This study examined the proportion of individuals in various cohorts who had had premarital sex (defined as either having had vaginal intercourse before first marrying or ever having had intercourse and never having married) by various ages. Methods. Data from four cycles of the National Survey of Family Growth, 1982–2002, and event history analysis techniques, including Kaplan-Meier lifetable procedures and Cox proportional-hazards regression models, were used to examine the incidence of premarital sex by gender and historical cohort. Results. Data from the 2002 survey indicate that by age 20, 77% of respondents had had sex, 75% had had premarital sex, and 12% had married; by age 44, 95% of respondents (94% of women, 96% of men, and 97% of those who had ever had sex) had had premarital sex. Even among those who abstained until at least age 20, 81% had had premarital sex by age 44. Among cohorts of women turning 15 between 1964 and 1993, at least 91% had had premarital sex by age 30. Among those turning 15 between 1954 and 1963, 82% had had premarital sex by age 30, and 88% had done so by age 44. Conclusions. Almost all Americans have sex before marrying. These findings argue for education and interventions that provide the skills and information people need to protect themselves from unintended pregnancy and sexually transmitted diseases once they become sexually active, regardless of marital status.
Graft Augmentation in Surgical Repair of Anterior Vaginal Wall Prolapse

Prolapse of the anterior vaginal wall is one of the most common conditions affecting women worldwide with prevalence rates reported as high as 50%. Surgical repair typically involves either anterior colporrhaphy or paravaginal defect repair depending upon the type of defect present. These repairs are often associated with high rates of recurrence. In an effort to reduce these rates and improve outcomes, graft augmentation with either biological or synthetic materials has been proposed. Significant improvements in outcome have been shown when graft augmentation is used. We present here a review of these procedures with and without graft reinforcement as well as the current report supporting their use.
Functional recovery of completely denervated muscle by direct nerve transplantation

can be controlled by the use of nerve, conditioned medium derived from neural cells or neurotrophic factors (agrin). These results suggest that pre-formation of NMJ prior to implantation of muscle cells may allow for more efficient neural integration and accelerate the recovery of muscle function. Furthermore, rapid neural integration of neural tissue would decrease the incidence of muscle atrophy and scarring.
Suppression of Oxidative Stress by Resveratrol After Isometric Contractions in Gastrocnemius Muscles of Aged Mice

This study tested the hypothesis that resveratrol supplementation would lower oxidative stress in exercised muscles of aged mice. Young (3 months) and aged (27 months) C57BL/6 mice received a control or a 0.05% trans-resveratrol-supplemented diet for 10 days. After 7 days of dietary intervention, 20 maximal electrically evoked isometric contractions were obtained from the plantar flexors of one limb in anesthetized mice. Exercise was conducted for three consecutive days. Resveratrol supplementation blunted the exercise-induced increase in xanthine oxidase activity in muscles from young (25%) and aged (53%) mice. Resveratrol lowered H(2)O(2) levels in control (13%) and exercised (38%) muscles from aged animals, reduced Nox4 protein in both control and exercised muscles of young (30%) and aged mice (40%), and increased the ratio of reduced glutathione to oxidized glutathione in exercised muscles from young (38%) and aged (135%) mice. Resveratrol prevented the increase in lipid oxidation, increased catalase activity, and increased MnSOD activity in exercised muscles from aged mice. These data show that dietary resveratrol suppresses muscle indicators of oxidative stress in response to isometric contractions in aged mice.