cssi/SciSciGPT-SciSciNet huggingface dataset:
Enhancement of the Long-Wavelength Sensitivity of Optogenetic Microbial Rhodopsins by 3,4-Dehydroretinal

Electrogenic microbial rhodopsins (ion pumps and channelrhodopsins) are widely used to control the activity of neurons and other cells by light (optogenetics). Long-wavelength absorption by optogenetic tools is desirable for increasing the penetration depth of the stimulus light by minimizing tissue scattering and absorption by hemoglobin. A2 retinal (3,4-dehydroretinal) is a natural retinoid that serves as the chromophore in red-shifted visual pigments of several lower aquatic animals. Here we show that A2 retinal reconstitutes a fully functional archaerhodopsin-3 (AR-3) proton pump and four channelrhodopsin variants (CrChR1, CrChR2, CaChR1, and MvChR1). Substitution of A1 with A2 retinal significantly shifted the spectral sensitivity of all tested rhodopsins to longer wavelengths without altering other aspects of their function. The spectral shift upon substitution of A1 with A2 in AR-3 was close to that measured in other archaeal rhodopsins. Notably, the shifts in channelrhodopsins were larger than those measured in archaeal rhodopsins and close to those in animal visual pigments with similar absorption maxima of their A1-bound forms. Our results show that chromophore substitution provides a complementary strategy for improving the efficiency of optogenetic tools.
Patient encounters by primary care nurse students.

Student-patient encounter data were systematically documented. Health problems identified by primary care nurse students were classified and analyzed. Primary health care practicums in three areas of specialization were obstetric-gynecologic, general adult, and pediatric services. A student-patient encounter form was constructed to record encounter data. A total of 1,689 encounter forms were completed by 30 nurse students enrolled in primary health care practicums during the years 1972–75. The identified health problems were classified by the International Classification of Diseases Adapted for Use in the United States. The results indicated: (a) the focus of primary health care for obstetric-gynecologic and pediatric patients was on health maintenance, whereas the focus for general adult patients was on illness care; (b) symptoms and ill-defined health conditions were frequently encountered by the students, particularly with general adult patients; (c) a cluster of health problems was identified for each of the three areas of specialization. The findings seemed to justify the need to develop a health problem classification system for primary health care.
Target identification performance as a function of spurious response: aliasing with respect to the half sample rate

The sampling limitations associated with focal plane array imagers caused an aliased signal that corrupts the image. The aliased signal is a function of pre-sample blur, sampling frequency, and post-blur or image reconstruction. Previous experiments at the U.S. Army Night Vision and Electronic Sensors Directorate have quantified the effect of aliasing on the task of infrared target identification. Based on data from these experiments, the MTF Squeeze model was developed. The degraded performance due to under- sampling was modeled as an increase in system blur or, equivalently, a contraction or `squeeze' in the MTF. This paper describes the results of numerous sampling experiments.
Genetic medicines: treatment strategies for hereditary disorders.

The treatment of the more than 1,800 known monogenic hereditary disorders will depend on the development of 'genetic medicines' — therapies that use the transfer of DNA and/or RNA to modify gene expression to correct or compensate for an abnormal phenotype. Strategies include the use of somatic stem cells, gene transfer, RNA modification and, in the future, embryonic stem cells. Despite the efficacy of these technologies in treating experimental models of hereditary disorders, applying them successfully in the clinic is a great challenge, which will only be overcome by expending considerable intellectual and economic resources, and by solving societal concerns about modifications of the human genetic repertoire.
Comments on57Fe Mössbauer spectra for Kramers doublets: A phenomenological interpretation

A static effective spinS=1/2 Hamiltonian is usually specified by a phenomenonological parameter, set, but the typical choice of parameters could be inappropriate. Two main issues are addressed: (i) Which spin Hamiltonian parameters are observable at a given applied field strength, and (ii) how should one deal with skewsymmetric components of the electronic Zeeman and magnetic hyperfine tensors that can be present for spin-coupled multinuclear complexes. Certain Mossbauer experiments were selected, somewhat arbitrarily, as examples; this analysis can be applied to other spectroscopic techniques as well.
Distal sensory nerve conduction of the superficial peroneal nerve: new method and its clinical application.

The superficial peroneal nerve subserves sensation on the entire surface of the dorsum of the foot, except in small areas. All previously reported techniques for evaluating nerve conduction along this nerve tested a proximal portion of the nerve. We report a new method for evaluating sensory nerve conduction of the four branches of the distal superficial peroneal nerve. Two branches to the second and third toes of the medial dorsal cutaneous nerve and two branches to the fourth and fifth toes of the intermediate dorsal cutaneous nerve were studied orthodromically and antidromically in 37 feet of 21 normal volunteers using surface stimulating and recording electrodes and with a distance of 10 cm between the stimulating and recording electrodes. Maximum nerve conduction velocities (NCV) ranged from 41.8 to 46.9 m/s, and mean response amplitude ranged from 6.5 to 7.6 μV with the orthodromic technique. Values for NCV were almost identical when elicited by antidromic and orthodromic techniques, but response amplitudes were higher with the antidromic technique. Mean amplitudes of the distal superficial peroneal nerve were about 50% of the proximal superficial peroneal, and the conduction velocity in the distal superficial peroneal was slower than that in the proximal superficial peroneal nerve, by 8–14 m/s. In seven cases, distal superficial peroneal neuropathy was confirmed with this technique: two with proper digital neuropathy, two with medial dorsal cutaneous neuropathy, and three with intermediate dorsal cutaneous neuropathy. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 689–694, 2001
Annular atrophic connective tissue panniculitis of the ankles

A case of annular lipoatrophy of the ankles in a 4-year-old girl is presented. Histologically a lobular lymphohistiocytic panniculitis with masses of foam cells was present. This pattern resembles that seen in atrophic connective tissue panniculitis. The patient responded to treatment with prednisone and dapsone and now has residual lipoatrophy.
False Memories and Persuasion Strategies

Research on false memories, which has increased drastically in the past decade, has mainly focused on the cognitive influences that lead to the creation of false memories, such as the theoretical c...
Gelatin methacrylate microspheres for controlled growth factor release

Gelatin has been commonly used as a delivery vehicle for various biomolecules for tissue engineering and regenerative medicine applications due to its simple fabrication methods, inherent electrostatic binding properties, and proteolytic degradability. Compared to traditional chemical cross-linking methods, such as the use of glutaraldehyde (GA), methacrylate modification of gelatin offers an alternative method to better control the extent of hydrogel cross-linking. Here we examined the physical properties and growth factor delivery of gelatin methacrylate (GMA) microparticles (MPs) formulated with a wide range of different cross-linking densities (15-90%). Less methacrylated MPs had decreased elastic moduli and larger mesh sizes compared to GA MPs, with increasing methacrylation correlating to greater moduli and smaller mesh sizes. As expected, an inverse correlation between microparticle cross-linking density and degradation was observed, with the lowest cross-linked GMA MPs degrading at the fastest rate, comparable to GA MPs. Interestingly, GMA MPs at lower cross-linking densities could be loaded with up to a 10-fold higher relative amount of growth factor than conventional GA cross-linked MPs, despite the GA MPs having an order of magnitude greater gelatin content. Moreover, a reduced GMA cross-linking density resulted in more complete release of bone morphogenic protein 4 and basic fibroblast growth factor and accelerated release rate with collagenase treatment. These studies demonstrate that GMA MPs provide a more flexible platform for growth factor delivery by enhancing the relative binding capacity and permitting proteolytic degradation tunability, thereby offering a more potent controlled release system for growth factor delivery.
Multi-gas transportation and electrochemical performance of a polymer electrolyte fuel cell with complex flow channels

Abstract A three-dimensional (3D) numerical model associating the heat/mass transfer and the electrochemical reaction in a proton exchange membrane (PEM) fuel cell is developed in this study, and a miniaturized PEM fuel cell with complex flow channels is simulated. The numerical computation is based on the finite-volume method. Governing equations for flow and heat/mass transfer are coupled with the electrochemical reactions and are solved simultaneously. The latent heat from the condensation of water vapor in cathode channel, if any, is considered. The perimeters of the bipolar plates are also included in the computational domain to account for their heat conduction effect. The miniaturized PEM fuel cell has a membrane electrode assembly (MEA) sandwiched by two brass bipolar plates etched with a number of winding gas channels with a flow area of 250 μm ×250 μm. The influence of anode gas humidity on the performance of the fuel cell is investigated through model prediction. Finally, field details of velocity, mass fraction and electromotive force are illustrated and discussed.
Changes in adrenal status affect hypothalamic thyrotropin-releasing hormone gene expression in parallel with corticotropin-releasing hormone

Glucocorticoids are well known to influence the secretion of TSH from the anterior pituitary gland, although it is uncertain whether its site of action is on the hypothalamus, pituitary, or both. To determine whether glucocorticoids can modulate the concentration of pro-TRH gene expression in hypothalamic hypophysiotropic neurons, we measured the content of pro-TRH messenger RNA (mRNA) in the paraventricular nucleus (PVN) of adrenalectomized and corticosterone- and dexamethasone-treated rats compared to that in control populations using in situ hybridization histochemistry. Adrenalectomy resulted in the expected increase in corticotropin-releasing hormone mRNA in the PVN and was accompanied by a parallel rise in pro-TRH mRNA (68.3%; P < 0.05). Conversely, corticosterone and dexamethasone both resulted in profound reduction in corticotropin-releasing hormone mRNA in the PVN and a parallel reduction in pro-TRH mRNA (43.2% and 73.2% respectively; P < 0.05). No significant differences were observed in pro-TRH...
Nonequilibrium morphology development in seeded emulsion polymerization. IV. Influence of chain transfer agent

We performed a series of experiments to study the effect of a chain transfer agent, n-dodecyl mercaptan (n-DM), on the development of morphology in composite latex particles. The morphologies were determined using a combination of transmission electron microscopy, differential scanning calorimetry, and surfactant titration. The polymer molecular weights were reduced up to 10-fold with n-DM levels up to 1.4% in the monomer. The addition of n-DM can increase the extent to which second-stage polymer domains are formed within the interior regions of the seed particles, but this is only expected under specific conditions. Numerical simulations support this conclusion. We also observed that the reduction in the molecular weight of the second-stage polymer did not significantly increase the extent of phase separation and morphology rearrangement within the particles. The overall effect on the morphology was limited. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 945–957, 2006
Dystrophic Changes in Extraocular Muscles after Gamma Irradiation in mdx:utrophin+/− Mice

Extraocular muscles (EOM) have a strikingly different disease profile than limb skeletal muscles. It has long been known that they are spared in Duchenne (DMD) and other forms of muscular dystrophy. Despite many studies, the cause for this sparing is not understood. We have proposed that differences in myogenic precursor cell properties in EOM maintain normal morphology over the lifetime of individuals with DMD due to either greater proliferative potential or greater resistance to injury. This hypothesis was tested by exposing wild type and mdx:utrophin+/− (het) mouse EOM and limb skeletal muscles to 18 Gy gamma irradiation, a dose known to inhibit satellite cell proliferation in limb muscles. As expected, over time het limb skeletal muscles displayed reduced central nucleation mirrored by a reduction in Pax7-positive cells, demonstrating a significant loss in regenerative potential. In contrast, in the first month post-irradiation in the het EOM, myofiber cross-sectional areas first decreased, then increased, but ultimately returned to normal compared to non-irradiated het EOM. Central nucleation significantly increased in the first post-irradiation month, resembling the dystrophic limb phenotype. This correlated with decreased EECD34 stem cells and a concomitant increase and subsequent return to normalcy of both Pax7 and Pitx2-positive cell density. By two months, normal het EOM morphology returned. It appears that irradiation disrupts the normal method of EOM remodeling, which react paradoxically to produce increased numbers of myogenic precursor cells. This suggests that the EOM contain myogenic precursor cell types resistant to 18 Gy gamma irradiation, allowing return to normal morphology 2 months post-irradiation. This supports our hypothesis that ongoing proliferation of specialized regenerative populations in the het EOM actively maintains normal EOM morphology in DMD. Ongoing studies are working to define the differences in the myogenic precursor cells in EOM as well as the cellular milieu in which they reside.
Early Preventive Dental Visits for Low Risk Children may Have Limited Benefit

Article Title and Bibliographic Information Effect of early preventive dental visits on subsequent dental treatment and expenditures. Beil H, Rozier RG, Preisser JS, Stearns SC, Lee JY. Med Care 2012 Sep;50(9):749-56. Reviewer Jonathan D. Shenkin, DDS, MPH Purpose/Question To determine dental treatment procedures at ages 43 to 72 months among children who received a dental preventive visit before 18 months of age versus those who received them up to 42 months of age Source of Funding US Agency for Healthcare Research and Quality and the National Institutes of Health Type of Study/Design Retrospective cohort study Level of Evidence Level 3 Strength of Recommendation Grade Not applicable
Transverse screw dislocations: A source of twist in crystalline polymer ribbons

Abstract A new model to explain the twisting of ribbonlike crystals within spherulites is proposed. The model is based on the inherent twisting perpendicular to the axis of a screw dislocation. In the proposed model a sequence of transverse screw dislocations of the same sign are spaced along the ribbon axis. The magnitude of the twist given by such a string of dislocations is calculated, and the mean dislocation spacings needed to give the measured degrees of twist are noted and found to be not unreasonable. The model also predicts the correct form of the temperature dependence of the degree of twist. An interpretation of the extant model of polymer ribbons is presented, whereby the nature of the orientation of the polymer chains within the crystals and the folding of chains at the ribbon surfaces cause the sign of the dislocations to be maintained and control the sign of the twist throughout the spherulite.
Broadband interferometer for measuring transmitted wavefronts of optical band pass filters for Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS)

The transmitted wavefronts of optical filters for he Hubble Space Telescope (HST) advanced camera for surveys (ACS) are characterized using the Wildly and Openly Modified Broadband Achromatic Twyman Green (WOMBAT) Interferometer developed in the NASA/GSFC Optics Branch's Diffraction Grating Evaluation Facility. Because only four of thirty-three of ACS's optical bandpass filters transmit the 633 nm light of most commercial interferometers, a broadband interferometer is required to verify specified transmitted wavefront of ACS filters. WOMBAT's design is a hybrid of the BAT2 interferometer developed for JPL used for HST wide field and planetary camera II filters and a WYKO 400 phase shifting interferometer. It includes a broadband light source, monochromator, off-axis, parabolic collimating and camera mirrors, an aluminum-coated fused silica beamsplitter, flat retroreflecting mirrors for the test and reference arms, and a UV-sensitive CCD camera. An outboarded, piezo-electric phase shifter holds the flat mirror in the interferometer's reference arm. The interferometer is calibrated through interaction between the WYKO system's software and WOMBAT hardware for the test wavelength of light entering the beamsplitter. Phase-shifted interferograms of the filter mounted in the tests arm are analyzed using WYKO's vision for optical testing software. Filters as large as 90 mm in diameter have been measured over a wavelength range from 200 to 1100 nm with a ACS fixed bandpass and spatially-variable bandpass filters for a variety of wavelengths.
Loop detection in surface patch intersections

Abstract A condition is presented for guaranteeing that all branches of the curve of intersection of two parametric surfaces patches contain a point on at least one of the patch boundary curves. This is of value because it eliminates a robustness limitation which arises when computing surface intersections using the marching method, namely, assuring that all branches of the intersection curve have been found. The intersection curve of any two surface patches meeting the prescribed condition can be computed by locating points where patch boundary curves intersect the opposing patch, and then using those points as starting points for the marching algorithm.
A Response to Chaos: The United States, the Great Leap Forward, and the Cultural Revolution, 1961-1968

During the 1960s, the People's Republic of China (PRC) faced two periods of severe turbulence. The first came out of the Great Leap Forward, which began in 1958. Although the Great Leap Forward of ficially ended in 1960, its effects reverberated well into the decade. The second was the Cultural Revolution, which the Chinese leader ship initiated in 1966 and terminated in early 1969. During both peri ods, the United States knew China was in turmoil, but the administrations of John F. Kennedy and Lyndon B. Johnson adopted very different responses. The former initially considered altering ex isting policy to help the Chinese people. Ultimately, however, a com bination of domestic and foreign policy developments compelled the Kennedy administration to stick with the hard-line stance of its pre decessors. The Johnson administration, by way of contrast, adopted a more flexible position toward China as changes on the domestic and foreign policy scenes, including the situation in China, the Vietnam War, as well as modifications in the American public's view of the PRC, provided greater latitude in considering the bilateral relation ship. As a result, the Johnson White House noticeably facilitated Rich ard Nixon's much-heralded efforts to achieve a Sino-American rapprochement with his dramatic trip in 1972. Problems in Sino-American relations came about in the late 1940s when it became increasingly clear that China would come under Com munist control. The Truman administration hardened its stance to ward the mainland, an attitude that was solidified in 1950 after the PRC entered the Korean War. Washington beefed up its emerging policy to contain the threat posed by China with a three-pronged strategy. The first aspect was to increase military aid to those nations around China's periphery (or, in Korea, to engage in actual warfare). The sec ond consisted of providing economic aid to nations in East Asia to help combat communism by imposing controls on trade with Beijing, thus limiting China's economic and military potential. Third was a design to isolate the PRC on the world political stage. The United States refused to recognize the Communist government and urged other
Vibration-internal rotation interactions in molecules containing a symmetric top group

Abstract The vibration-internal rotation interactions in molecules that contain a single symmetric top are studied by means of a model consisting of two internally rigid groups that are allowed to vibrate as well as rotate relative to each other. The matrix mechanical Hamiltonian for the model is obtained and the diagonalization of the corresponding secular determinant that contains large off-diagonal terms is accomplished. An expression for the J = 0 → 1, Δ K = 0 transition is obtained. Numerical calculations are carried out for the case of methyl alcohol in order to compare the theory with the observed spectrum. A qualitative fit is found, the major contributions being the in-plane vibrations of the two rigid groups. The lack of detailed agreement is attributed to the neglect of those vibrations which distort the methyl group, and to insufficient knowledge concerning the infrared spectrum of the molecule.
Telerobotics issues in space application

Abstract This paper presents the research issues associated with the application of telerobotics in space. Included in this paper are a review of previous research in space telerobotics, a description of the University's research laboratory, and the University's experimental program addressing several selected telerobotics issues.
Superiority of targeted neonatal echocardiography for umbilical venous catheter tip localization: accuracy of a clinician performance model.

Superiority of targeted neonatal echocardiography for umbilical venous catheter tip localization: accuracy of a clinician performance model
Ethanol modulation of GABAergic transmission: The view from the slice

For almost three decades now, the GABAergic synapse has been the focus of intense study for its putative role in mediating many of the behavioral consequences associated with acute and chronic ethanol exposure. Although it was initially thought that ethanol interacted solely with the postsynaptic GABAA receptors that mediate the majority of fast synaptic inhibition in the mammalian central nervous system (CNS), a number of recent studies have identified novel pre- and postsynaptic mechanisms that may contribute to the acute and long-term effects of ethanol on GABAergic synaptic inhibition. These mechanisms appear to differ in a brain region specific manner and may also be influenced by a variety of endogenous neuromodulatory factors. This article provides a focused review of recent evidence, primarily from in vitro brain slice electrophysiological studies, that offers new insight into the mechanisms through which acute and chronic ethanol exposures modulate the activity of GABAergic synapses. The implications of these new mechanistic insights to our understanding of the behavioral and cognitive effects of ethanol are also discussed.
The von Hippel-Lindau protein interacts with heteronuclear ribonucleoprotein a2 and regulates its expression.

The product of the von Hippel-Lindau (VHL) tumor suppressor gene, pVHL, functions as a ubiquitin-protein isopeptide ligase in regulating HIF-1 protein turnover, thus accounting for the increased transcription of hypoxia-inducible genes that accompanies VHL mutations. The increased vascular endothelial growth factor mRNA stability in cells lacking pVHL has been hypothesized to be due to a similar regulation of an RNA-binding protein. We report the expression of the GLUT-1 3′-untranslated region RNA-binding protein, heteronuclear ribonucleoprotein (hnRNP) A2, is specifically increased in pVHL-deficient cell lines. Enhanced hnRNP A2 expression was apparent in all cell fractions, including polysomes, where a similar modest effect on hnRNP L (a GLUT-1 and VEGF 3′-untranslated region-binding protein), was seen. Steady state levels of hnRNP A2 mRNA were unaffected. Regulation of hnRNP A2 levels correlated with the ability of pVHL to bind elongin C. Proteasome inhibition of cells expressing wild type pVHL selectively increased cytoplasmic hnRNP A2 levels to that seen in pVHL-deficient cells. Finally, an in vivo interaction between pVHL and hnRNP A2 was demonstrated in both the nucleus and the cytoplasm. Collectively, these data indicate that hnRNP A2 expression is regulated by pVHL in a manner that is dependent on elongin C interactions as well as functioning proteasomes.
Passive transfusion of human chorionic gonadotropin from plasma donated during pregnancy

Although fresh frozen plasma (FFP) prepared from autologous blood donated during pregnancy has frequently been given to homologous recipients at our institution, one transfusion resulted in an unanticipated diagnostic dilemma. A 31-year-old woman with disseminated intravascular coagulation of unclear etiology was transfused with multiple units of FFP, including 2 from pregnant autologous donors. A serum human chorionic gonadotropin (HCG) assay, performed because of the possibility that the patient's illness was a complication of unrecognized pregnancy, was positive using a blood sample drawn 7 h after the transfusions. An extensive evaluation was completed before the possibility of passive transfer of hormone from blood products was considered. Retrospective testing of serum samples established that HCG appeared in the patient's serum only after the first FFP transfusion from a pregnant autologous donor. In 8 other recipients of 1 or 2 units of FFP from pregnant autologous donors, post-transfusion HCG levels ranged between 96 and 1,750 mIU/ml. Of 15 recipients of packed red blood cells from pregnant autologous donors, only patients with renal failure or recipients of multiple units developed positive HCGs, which were always less than or equal to 85 mIU/ml. The differential diagnosis of a positive pregnancy test in a recently transfused individual should include the possibility of passively acquired hormone.
Poems From Swimming in the Shallow End: A Collection-in-Progress

The seminal studies of Robert and Helen Lynd on Middletown (Muncie, Indiana) strongly influenced the author as a young high school student who grew up in Muncie. In time, he realized that the quantitative research of the Lynds (and later Theodore Caplow) accurately but incompletely captured his real experience. Over time, the author broadened his perspective, and these poems are the result of years of shaping narratives into a collection that reflects the growth of a small-town mind, not a disparaging phrase but an accurate reflection of the state of mind that keeps some people in their first communities.
Experimental, limited vocabulary, speech recognizer

An experimental speech recognizer is described which exhibits a high level of performance and is practical in terms of size, weight, cost, and power consumption. High recognition performance is achieved by employing the limited vocabulary approach and utilizing a simple set of parameter extractors based upon the single equivalent formant theory conceived and developed by one of the authors. Recognition logic for a vocabulary word consists of circuitry for testing the levels and movements of three parameter waveforms to determine whether they conform to the conditions of acceptability for the particular word as found from parameter data for a large number of speakers. The recognizer presently responds to the spoken digits OH through NINE with a recognition accuracy of 90 percent and an error rate of one percent on live utterances by speakers who contributed the design samples, and only slightly lower than this on other male speakers of similar speech characteristics. The recognizer occupies a volume of less than 0.8 cubic foot exclusive of microphone, indicator, and power supplies, consumes less than 30 watts, and shows promise of a very low eventual cost per word.
Rates of clustering in Strassen's LIL for Brownian motion

If {W(t): 0≦t≦∞} denotes standard Brownian motion and then with probability one the random sequence $$\{ W(n( \cdot ))/(2nL_2 n)^{1/2} :n \geqslant 1\} $$ converges to and clusters throughoutK in the uniform norm. This is Strassen's LIL for Brownian motion, and here we examine the rate at which this convergence and clustering takes place, improving some results of K. Grill.
Management of Forefoot Injuries in the Athlete

Athletes who participate in high-impact sports are at higher risk for acute and chronic forefoot injuries. We review the diagnosis and treatment techniques for the most common conditions that produce forefoot pain in the athlete: metatarsal stress fracture, hallux valgus, hallux rigidus, second metatarsophalangeal synovitis and instability, turf toe, and sesamoid pathologies. These conditions and their treatments are discussed in the context of forefoot anatomy and biomechanics. Both nonoperative and operative techniques are highlighted.
Non-right-orderable 3-manifold groups

We exhibit infinitely many hyperbolic 3-manifold groups that are not right-orderable. Department of Mathematics, Washington University, St Louis, MO 63130 e-mail: roberts@math.wustl.edu shareshi@math.wustl.edu Received by the editors December 12, 2007. Published electronically July 26, 2010. R. Roberts was partially supported by National Science Foundation grants DMS-9971333 and DMS-0312442. J. Shareshian was partially supported by National Science Foundation grants DMS0070757, DMS-0300483 and DMS-0604233. AMS subject classification: 20F60, 57M05, 57M50. 1
How fast does rock varnish grow

Rates of rock-varnish accumulation have never been systematically documented owing to the difficulty in accurately determining both varnish thickness and age. In this study, we quantitatively assess varnish-accumulation rates through thin sectioning and microscopic examination of rock varnish from radiometrically dated geomorphic features of late Quaternary age in the western United States drylands. Our data indicate that rock varnish grows at rates ranging from <1 to 40 µm/k.y. on subaerially exposed rock surfaces and rarely reaches a thickness exceeding 200 µm regardless of age. Our data also indicate that varnish-accumulation rates vary greatly from sample to sample at a given site, suggesting that varnish thickness does not correlate with the age of the associated geomorphic feature, invalidating the potential use of varnish thickness as a relative age indicator in geomorphology and archaeology. Nevertheless, being the slowest known accumulating terrestrial sedimentary deposit, rock varnish constitutes a unique long-term microscale sedimentary archive of past environmental changes in deserts.
Supply interruptions in a lost-sales inventory system with random lead time

This paper presents an analytical model for computing the stationary distribution of the on-hand inventory in a continuous-review inventory system with compound Poisson demand, Erlang distributed lead time, and lost sales, where the supplier can assume one of the two "available" and "unavailable" states at any point in time according to a continuous-time Markov chain. Exact analytical expressions are derived for the special case where demand sizes are exponentially distributed, and some cost minimization numerical results are presented.
Data Acquisition with a PDP-11/44 and MBD-11 Branch Driver with the UNIX Time-Sharing System

A data acquisition system that provides real-time data acquisition and control, and on-line data analysis facilities has been recently installed. A PDP-11/44 is interfaced to CAMAC via a MBD-11 microprogrammable parallel branch driver. Both system and user software has been implemented in the structured high level "C" language in the UNIX time-sharing environment. Implementation of the system is discussed.
The gamma band effect for episodic memory encoding is absent in epileptogenic hippocampi

Abstract Objective The analysis of hippocampal local field potentials in humans during the encoding of episodic memories has revealed that a robust increase in gamma band oscillatory power predicts successful item encoding, termed the gamma band subsequent memory effect (SME). No previous investigation has looked for differences in this pattern between epileptogenic and non-epileptogenic sources; we sought to examine the gamma band effect in seizure patients to address this question. Methods We recorded hippocampal activity in nine patients who underwent stereoelectroencephalography for seizure localization and also performed the Free Recall task, a standard test of episodic memory. We compared gamma band oscillatory activity between 15 electrodes localized to epileptogenic hippocampi and 24 electrodes in non-epileptogenic hippocampi. Results The epileptogenic hippocampi exhibited a significant decrease in gamma band power during successful item encoding, whereas the non-epileptogenic group exhibited the expected positive gamma band effect ( t (37)=4.69, p 0.0001 ). Conclusions The typical gamma band effect is reversed for epileptogenic hippocampi. Significance This is the first study to demonstrate a difference for epileptogenic hippocampi for an important oscillatory pattern that normally predicts successful item encoding. Patients with epilepsy suffer selective impairment of episodic memory ability, so our findings are especially relevant for clinicians and memory researchers alike.
Fatty acyl esters potentiate fatty acid induced activation of protein kinase C

Summary Purified rat pancreas protein kinase C (PKC) is activated by unsaturated free fatty acids (oleic and arachidonic). The ethyl esters of these fatty acids are ineffective as enzyme activators. However, when the ethyl esters are added in combination with a free fatty acid, there is significant enhancement of enzyme activation. Nearly optimal PKC activation was obtained when non-activating ethyl oleate or ethyl arachidonate was added to sub-optimally activating concentrations of oleic or arachidonic acids. In addition to the ethyl esters, 1-monooleylglycerol also had a potentiating effect on PKC activation by oleic acid. However, the degree of activation observed in the presence of a free fatty acid and an acyl ester of the fatty acid quantitatively never surpassed that produced by sn-1,2-dioleylglycerol. Our findings indicate that significant PKC activation can be achieved by presenting the enzyme with an environment which we believe approximates the structural characteristics of the endogenous activator, sn-1,2-diacylglycerol.
When only random testing will do

In some circumstances, random testing methods are more practical than any alternative, because information is lacking to make reasonable systematic test-point choices. This paper examines some situations in which random testing is indicated and discusses issues and difficulties with conducting the random tests.
The synthesis of 5-substituted ring E analogs of methyllycaconitine via the Suzuki–Miyaura cross-coupling reaction

Abstract Novel 3,5-disubstituted ring E analogs of methyllycaconitine were prepared and evaluated in nicotinic acetylcholine receptor binding assays. The desired analogs were prepared through the Suzuki–Miyaura cross-coupling reaction of methyl 5-bromo-nicotinate. The Suzuki–Miyaura cross-coupling reactions of pyridines with electron withdrawing substituents have not been extensively described previously.
INDUCED RESISTANCE TO ELECTROSHOCK AND AUDIOGENIC SEIZURES IN INBRED STRAINS OF MICE.

SummaryA protective effect against both audiogenic and electroshock convulsions in mice has been demonstrated for the compound 2,4 dichlorophenoxyacetic acid, and for the vital dye trypan blue. The mechanism involved was not revealed but attention was directed to the finding that both substances are not depressants, and that they are probably centrally acting. The threshold to electroshock convulsions was compared in 2 sublines of the Swiss Webster strain of mice, selected for susceptibility and resistance to audiogenic seizures, respectively. No significant difference in electroshock threshold between the two lines was observed.
Viscosity of highly polarized very dilute He-3-He-4 mixtures

We present vibrating - wire viscosity measurements on a very dilute 3He-4He mixture (χ3 = 150 ppm) in fields up to 14.8 T and temperatures down to 3 mK. The 3He spin polarization is greater than 99% for the highest field and lowest temperature used. In these conditions, the s-wave scattering rate decreases due to a lack of quasiparticles with the minority spin state. This enhances all transport coefficients including the viscosity. At the lowest temperature, the hydrodynamic damping of the viscometer in a 14.8 T field was more than 10 times larger than in low fields. This indicates a many-fold increase in the mixture viscosity due to spin polarization.
Issues and Challenges in Gatekeeping: A Framework for Implementation

Social work educators' role in gatekeeping within BSW and MSW academic programs continues to be a concern and challenge for the profession. Social work programs are the entry point in which students develop the required competencies to practice within the field. The social work literature on gatekeeping is extensive and expansive. The literature reviews and addresses the importance and need for gatekeeping as well as challenges in implementing gatekeeping within social work programs. This paper reviews the literature on gatekeeping in social work programs, discusses the legal issues pertinent to gatekeeping, and identifies the challenges faced by social work programs in implementing gatekeeping procedures. The paper suggests an integrated conceptual framework using the Council on Social Work Education's Educational Policy and Accreditation Standards (EPAS) for competencies in gatekeeping in social work programs.
Marketing's promise for hospitals

S. Tamer Cavusgil is professor of marketing and director of the Center for Business and Economic Research at Bradley University, Peoria, Illinois. A business consultant to hospitals, Cavusgil has directed numerous studies on health care marketing. His "Guidelines tbr Export Market Research" appeared in the November-December 1985 issue of Business Horizons. Like management in many other service organizations, hospital administrators work with constituencies who may think that marketing is a dirty word. But doing business in a rapidly changing environment means planning and implementing strategic marketing.
Accurate prediction of clathrate hydrate phase equilibria below 300 K from a simple model

A simple thermodynamic model with only two adjustable parameters has been developed which can accurately correlate hydrate–liquid water–vapor (H–LW–V) phase equilibrium for single-guest gas hydrates at temperatures below 300 K. The approach combines the van der Waals–Platteeuw theory and the Peng–Robinson equation of state, and provides a unified treatment of the two fluid phases (liquid water and hydrocarbon). The present model compares favorably with other methods in the literature in terms of average absolute percent deviation (AAPD) from available experimental data. We further find that the accuracy of the calculations is insensitive to the solubility of guest molecules in liquid water.
Carrier Screening for Cystic Fibrosis, Gaucher Disease, and Tay-Sachs Disease in the Ashkenazi Jewish Population: The First 1000 Cases at New York University Medical Center, New York, NY

Background By late 1993, the genes for cystic fibrosis and Gaucher disease and the mutations common among Ashkenazi Jews had been identified. In response to these advances, heterozygote screening for cystic fibrosis and Gaucher disease was added to the more than 20-year-old Tay-Sachs disease screening program at New York University Medical Center, New York, NY. Objective To review the outcomes from the first 1000 patients screened through this program. Methods Patients and their referring physicians were informed about the new carrier tests. At the time of screening, patients could choose their tests (hexosaminidase A by enzyme analysis for Tay-Sachs disease or mutation analysis for cystic fibrosis and Gaucher disease). All partners of Tay-Sachs and cystic fibrosis carriers were tested. Prenatal diagnosis was offered and performed for carrier couples or mixed-marriage couples in whom the Ashkenazi Jewish partner was a carrier of Gaucher disease. Outcomes were measured by: (1) choice of tests, (2) decisions regarding prenatal diagnosis, and (3) phenotypes of children born to patients who underwent screening. Results The majority of Ashkenazi Jewish patients chose to have testing for all 3 diseases. If they previously underwent screening for Tay-Sachs disease, then they chose to undergo testing for cystic fibrosis and Gaucher disease. All carrier couples for each of these diseases went on to have prenatal testing. All mixed-marriage couples in whom the Jewish partner was found to be a carrier for Gaucher disease chose to have prenatal diagnosis. One fetus was identified as having cystic fibrosis. Since the program was initiated, no Ashkenazi Jewish baby has been born with any of these diseases at New York University Medical Center. Conclusions New tests can be readily incorporated into established heterozygote screening programs. The Ashkenazi Jewish population described herein tends to choose testing for all conditions for which heterozygote screening is available.
Asymmetrical processing of tachistoscopic inputs in undergraduates across sex, handedness, field-side, and fixation instructions.

Past studies have indicated that men as well as right-handers show a right-visual field (RVF) advantage for letter recall and a left-visual field (LVF) advantage for letter position recall, suggesting asymmetrical brain organization for these groups. To examine these laterality effects more closely, 96 undergraduates were tested in a tachistoscopic task; they were equally divided by sex and hand dominance. On each of the 48 trials, subjects were required to recall either the letters or respective letter positions within 4 x 4 matrices flashed to the right or left visual field for 100 msec. Subjects further received instructions prior to each trial cueing them as to the field in which the matrix would be positioned (i.e., left, right or neither). Analyses indicated that right-handed men showed the predicted RVF advantage for letters while only right-handed subjects evidenced a LVF advantage for letter positions. Instructions might have contributed to the observed sex difference with letters; this would imply that right-handers exclusively possessed this asymmetrical organization.
Rapid Solid-Phase Extraction of Dopamine, Serotonin, and Their Acidic Metabolites for High-Performance Liquid Chromatography with Electrochemical Detection

Abstract A rapid solid-phase extraction procedure utilizing C18 reverse-phase mini-columns has been established for dopamine, 3,4-dihydroxyphenylacetic acid, serotonin, and 5-hydroxyindoleacetic acid in tissue perfusate samples. The method rapidly separates the analytes from protein in albumin-containing tissue perfusates. The analytes which are recovered in high yield are then determined by high-performance liquid chromatography with electrochemical detection. The mean interassay coefficient of variation for the recovery of dopamine, 3, 4-dihydroxyphenylacetic acid, serotonin and 5-hydroxyindoleacetic acid was 12, 7, 13 and 8 percent, respectively.
EQUIRIPPLE APPROXIMATION OF FAN FILTERS

An efficient procedure for the approximation of two‐dimensional (2‐D) fan filters is presented. The Chebychev (or min‐max) error criterion is used to measure the optimality of the approximation as opposed to previous designs which use the least‐squares norm. Since the direct solution of a 2‐D Chebychev approximation problem is difficult, a change of variables is introduced to convert the 2‐D approximation problem into an equivalent 1‐D low‐pass filter approximation problem. The response is opptimized in the 1‐D domain, and then the change of variables is applied to obtain the 2‐D filter. Thus the techniques of 1‐D Chebychev approximation are applied to yield a 2‐D fan filter.
Role of pretreatment and conditioning processes on toxicity of lignocellulosic biomass hydrolysates

The Department of Energy’s Office of the Biomass Program has set goals of making ethanol cost competitive by 2012 and replacing 30% of 2004 transportation supply with biofuels by 2030. Both goals require improvements in conversions of cellulosic biomass to sugars as well as improvements in fermentation rates and yields. Current best pretreatment processes are reasonably efficient at making the cellulose/hemicellulose/lignin matrix amenable to enzymatic hydrolysis and fermentation, but they release a number of toxic compounds into the hydrolysate which inhibit the growth and ethanol productivity of fermentation organisms. Conditioning methods designed to reduce the toxicity of hydrolysates are effective, but add to process costs and tend to reduce sugar yields, thus adding significantly to the final cost of production. Reducing the cost of cellulosic ethanol production will likely require enhanced understanding of the source and mode of action of hydrolysate toxic compounds, the means by which some organisms resist the actions of these compounds, and the methodology and mechanisms for conditioning hydrolysate to reduce toxicity. This review will provide an update on the state of knowledge in these areas and can provide insights useful for the crafting of hypotheses for improvements in pretreatment, conditioning, and fermentation organisms.
InP/InGaAs SHBTs with 75 nm collector and ft> 500 GHz

InP/InGaAs single heterojunction bipolar transistors (SHBTs) are fabricated exhibiting current-gain cutoff frequencies, fT of 509 GHz. The 0.35×12 µm2 devices consist of a 25 nm graded base and a 75 nm collector, have a breakdown BVCEO of 2.7 V, and operate at current densities above 1100 kA/cm2. This work demonstrates clear progress toward a THz transistor.
Cyclotron Harmonic Amplification in Beams and Plasmas

ABSTRACT This paper concerns wave phenomena in electron beams and plasmas with internal motions, in the presence of a static magnetic field. It is known that axially-rotating beams show wave propagation when the Doppler-shifted frequency seen by the beam electrons is approximately a harmonic of the electron cyclotron frequency. Similar propagation in an infinite series of coupled modes can occur for beams and plasmas in which the electrons gyrate about the magnetic field lines, rather than the axis. Associated with each Doppler-shifted cyclotron harmonic, a slow and a fast space-charge wave are propagated along an electron beam. These sets of waves can interact with each other, with slow or fast wave circuits, or with a plasma, to yield growing waves. The nature of these interactions is discussed in the paper. It is suggested that this mechanism of wave amplification along an unneutralized electron beam may provide an explanation of the noise growth observed in electron beams from shielded guns, and in cr...