cssi/SciSciGPT-SciSciNet huggingface dataset:
Ultrafast dynamics of laser-metal interactions in additive manufacturing alloys captured by in situ X-ray imaging

Abstract Advanced in situ characterization is essential for determining the underlying dynamics of laser-material interactions central to both laser welding and the rapidly expanding field of additive manufacturing. Traditional characterization techniques leave a critical experimental gap in understanding the complex subsurface fluid flow and metal evaporation dynamics inherent in laser-induced heating of the metal. Herein, in situ ultra-high-speed transmission X-ray imaging is revealed to be essential for bridging this information gap, particularly via comparison with and validation of advanced multiphysics simulations. Imaging on submicrosecond timescales enables correlation between dynamics of the laser-generated vapor–liquid interface and melt pool surface instabilities in industrially relevant alloys. X-ray imaging and complimentary simulations reveal vapor depression oscillations and rapid expansion due to reflection of the processing laser from the front surface of the vapor depression. Pore formation studies at steady state and during prompt removal of laser heating at the end of track reveal that the rapidly solidifying melt pool traps pores near the base of the vapor-filled depression. Moreover, pores within the melt pool are entrained by Marangoni convection which overcomes the force of buoyancy and forces the pores downward from the surface immediately before solidification. Observed solidification kinetics, consistent with previous results, give insight into surface morphology and porosity in the processed material. The information presented here is key for defining the physical models that describe laser-material interaction and ultimately increases our understanding of the emerging field of laser-based metal additive manufacturing.
Vibrational state-specific model for dissociation and recombination of the O2( 3Σg-)+O( 3P) system in DSMC.

A vibrational state-specific model for dissociation and recombination reactions within the direct simulation Monte Carlo method is introduced to study the energy level dynamics of the O2 + O system. The state-resolved cross sections for vibrational relaxation and dissociation reactions are obtained from a rotationally averaged quasi-classical trajectory database based on the Varandas and Pais O2( 3Σg−)+O( 3P) potential energy surface. A two-step binary collision framework is outlined to characterize the vibrational state-resolved recombination probabilities, which are constrained by detailed balance for orbiting pair formation, and microscopic reversibility applied to the dissociation cross sections for orbiting pair stabilization. The vibrational state-to-state (STS) model is compared to the phenomenological total collision energy (TCE) and quantum kinetic (QK) models through a series of 0-d non-equilibrium relaxation calculations. A quasi-steady state (QSS) region is established in the vibrational temperature profiles of the TCE, QK, and STS models under non-equilibrium heating. This QSS region is a result of the competition between vibrational relaxation by vibrational-translational (VT) transitions and O2 dissociation. The duration of QSS predicted by the STS model is approximately ten and four times that of the TCE and QK model predictions, respectively, and the total time to reach equilibrium is approximately 3.5 times that of the TCE model and 1.5 times that of the QK model. A distinct QSS region is not observed in the non-equilibrium cooling case. This is attributed to the relatively rapid VT transitions that work to equilibrate the vibrational energy distribution upon recombination, which is comparatively slow. The total time to reach equilibrium by the STS model in the non-equilibrium cooling case is five times and three times greater than those of the QK and TCE models, respectively.
Assessment of the Reconstructed Pulmonary Circulation With Lung Perfusion Scintigraphy After Unifocalization and Repair of Tetralogy of Fallot With Major Aortopulmonary Collaterals.

Background:Pulmonary vascular supply in tetralogy of Fallot (TOF) with major aortopulmonary collaterals (MAPCAs) is highly variable. Our approach to surgical management of this condition emphasizes...
Time-varying transmission dynamics of Novel Coronavirus Pneumonia in China

Objectives: We aimed to estimate the basic and time-varying transmission dynamics of NCP across China, and compared them with SARS. Methods: Data on NCP cases by February 7, 2020 were collected from epidemiological investigations or official websites. Data on severe acute respiratory syndrome (SARS) cases in Guangdong Province, Beijing and HongKong during 2002-2003 were also obtained. We estimated the doubling time, basic reproduction number (R0) and time-varying reproduction number (Rt) of NCP and SARS. Measurements and main results: As of February 7, 2020, 34,598 NCP cases were identified in China, and daily confirmed cases decreased after February 4. The doubling time of NCP nationwide was 2.4 days which was shorter than that of SARS in Guangdong (14.3 days), Hong Kong (5.7 days) and Beijing (12.4 days). The R0 of NCP cases nationwide and in Wuhan were 4.5 and 4.4 respectively, which were higher than R0 of SARS in Guangdong(R0=2.3), Hongkong (R0=2.3), and Beijing (R0=2.6). The Rt for NCP continuously decreased especially after January 16 nationwide and in Wuhan. The R0 for secondary NCP cases in Guangdong was 0.6, and the Rt values were less than 1 during the epidemic. Conclusions: NCP may have a higher transmissibility than SARS, and the efforts of containing the outbreak are effective. However, the efforts are needed to persist in for reducing time-varying reproduction number below one.
Complex and Novel Arrhythmias Precede Stillbirth in Fetuses With De Novo Long QT Syndrome.

Background: Long QT syndrome (LQTS) is a leading cause of sudden cardiac death in early life and has been implicated in ≈10% of sudden infant deaths and unexplained stillbirths. The purpose of our ...
Prenatal sonographic diagnosis of holoprosencephaly

Objective To investigate the prenatal sonographic appearance of holoprosencephaly (HPE), and improve the diagnosis of this anomaly. Methods Thirty diagnosed or suspected HPE cases by prenatal ultrnsound were analyzed retrospectively from May 2001 to Nov. 2007. Intracranial structure, facial anomalies and other associated malformations were examined by prenatal ultrasound. Some received karyotyping or prenatal M-RI. Results HPE was confirmed in 25 cases (10 male and 15 female) through autopsy or follow-up and 5 were missed diagnosed or suspected as HPE by prenatal ultrasound, but hydroencephaly or porencephaly by autopsy. Alobar HPE was found in 21 cases in which ultrasound results were consistent with the final autopsy diagnosis. Semi-lobar HPE was detected in 4 cases. The diameters of the head were changed in 20 out of 24 cases(83.3%), especially 62.5% (15/24)with smaller BPD than the normal ones. The most common seen facial anomalies were midline anomalies (88.0%, 22/25) and all with ocular anomalies. Nasal anomalies were found in 11 cases, medial-cleft lip and/or palate in 11 eases and 10(40.0%) were assoeiated with complex congenital heart defects. Ten eases with HPE received karyotype and 5 were abnormal among which 4 with complex congenital heart defects. Conclusions Prenatal ultrasound is a useful tool in diagnosing HPE with highly accuracy. However, ultrasound itself fails in subtyping of HPE which can be compensated by MRL HPE is often associated with facial malformation and other multi-organ malformation, such as heart malformation. HPE is highly correlated with chromosomal abnormalities. Key words: Ultrasonography, prenatal; Holoprosencephaly
Adenosine-induced transient asystole to control intraoperative rupture of intracranial aneurysms: institutional experience and systematic review of the literature.

Background: Intraoperative rupture of an intracranial aneurysm is a life-threatening situation that carries a high risk of morbidity and mortality. Since 2000, adenosine has been used successfully ...
A QuICR test to diagnose Parkinson’s disease

Refined conditions permit rapid detection of proteopathic α-synuclein seeds in cerebrospinal fluid from patients with Parkinson’s disease.
Scope of Practice and Standards of Training Across the Clinical Professions

To improve the interdisciplinary knowledge and understanding of diverse career paths for behavior analysts, this chapter provides an overview of the education, practical training, and licensure standards for several clinical professions. Medicine is reviewed as the profession which has set the standards for training and professional practice regulation in the United States. Clinical psychology, social work, counseling, school psychology, and licensed behavior analyst career paths are discussed in parallel formats highlighting their training and regulatory similarities and differences. Each profession’s relationship with evidence-based practice (e.g., whether compulsory within the profession’s ethical standards) and opportunities for coursework and supervised practice grounded in behavioral principles are reviewed. The chapter closes with a discussion of future directions in the licensure of master’s level practitioners in health services psychology, an area with a broad scope of practice emphasizing improving functioning in all areas of behavioral and mental health.
New Treatment Options for Older Patients with Acute Myeloid Leukemia.

The treatment of acute myeloid leukemia (AML) has evolved considerably over the past several years. Advances in the field have historically benefited younger patients; however, a growing understanding of the molecular basis of leukemogenesis has brought multiple targeted agents to the clinic for patients of all ages. These therapies have expanded the therapeutic landscape for elderly patients from more than best supportive care and low-intensity monotherapy. In general, we currently utilize a backbone regimen of a hypomethylating agent (HMA) or low-intensity chemotherapy with the BCL-2 inhibitor venetoclax for the majority of elderly patients with newly diagnosed AML. For patients with targetable mutations, we employ a doublet/triplet strategy of HMA + a targeted inhibitor +/− venetoclax, often in the context of a clinical trial. CPX-351 is reserved for patients with secondary or therapy-related AML. In this review, we will outline our approach to the treatment of elderly patients with AML, with particular emphasis on recently approved agents and emerging novel therapies.
Learning from the Experiences of COVID-19 Survivors: A Descriptive Study

BackgroundThere are still many unanswered questions about the novel coronavirus, however, a largely underutilized source of knowledge are the millions of people who have recovered after contracting the virus. This includes majority of undocumented cases of the COVID-19 which are classified as mild or moderate and received little to no clinical care during the course of illness. ObjectiveTo document and glean insights from the experiences of persons with first-hand experience with coronavirus, especially the so-called mild to moderate cases that self-resolved in isolation. MethodsThis online-based survey study called C19 Insider Scoop recruited adult participants that are 18-years or older who reside in the United States and tested positive for COVID-19 or antibodies. Participants were recruited through various methods including online support groups for COVID-19 survivors, advertisement in local news outlets, and advertisement through professional and other networks. The main outcomes measured include knowledge on contraction/transmission of the virus, symptoms, and personal experiences on road to recovery. ResultsA total of 72 participants (53 females/19 males, ages 18 - 73 yrs. old, mean = 41-yrs.) from 22 U.S. states participated in this study. We found that the top known source of how people contracted the COVID-19 virus was through a family or household member (n=26 or 35%). This was followed by essential workers contracting the virus through the workplace (n=13 or 18%). Participants reported up to 27 less-documented symptoms that they experienced during their illness such as brain/memory fog, palpitations, ear pain/discomfort and neurological problems. In addition, 47 out of 72 participants (65%) reported that their symptoms lasted longer than the commonly cited 2-weeks even for mild cases of COVID-19. In our study, the mean recovery time was 4.5-weeks, and exactly one-half of survivors (50%) still experienced lingering symptoms of COVID-19 after an average of 65-days following illness onset. Additionally, 37 participants (51%) reported that they experienced stigma associated with having COVID-19. ConclusionThis study presents preliminary findings which suggests that emphasis on family/household spread of COVID-19 may be lacking and there is a general underestimation of the recovery time even for mild cases of the virus. Although a larger study is needed to validate these results, it is important to note that as more people experience COVID-19, insights from prior survivors can enable a more informed public, pave the way for others who may be affected, and guide further research.
Looking Back to Leap Forward: A Framework for Operationalizing the Structural Racism Construct in Minority Health Research.

Racism is now widely recognized as a fundamental cause of health inequali­ties in the United States. As such, health scholars have rightly turned their attention toward examining the role of struc­tural racism in fostering morbidity and mortality. However, to date, much of the empirical structural racism-health dispari­ties literature limits the operationalization of structural racism to a single domain or orients the construct around a White/ Black racial frame. This operationaliza­tion approach is incomprehensive and overlooks the heterogeneity of historical and lived experiences among other racial and ethnic groups. To address this gap, we present a theoreti­cally grounded framework that illumi­nates core mutually reinforcing domains of structural racism that have stratified opportunities for health in the United States. We catalog instances of structural discrimination that were particularly con­straining (or advantageous) to the health of racial and ethnic groups from the late 1400s to present. We then illustrate the utility of this framework by applying it to American Indians or Alaska Natives and discuss the framework’s broader implica­tions for empirical health research. This framework should help future scholars across disciplines as they identify and interrogate important laws, policies, and norms that have differentially constrained opportunities for health among racial and ethnic groups. Ethn Dis . 2021;31(Suppl 1):301-310; doi:10.18865/ed.31.S1.301
Scrutinizing disease states and regulation in human microglia.

Single-cell and bulk transcriptomics of adult human microglia from a population of individuals reveals activated states across several brain disorders and maps Alzheimer’s disease variants to microglia-enriched genes.
Nitric Oxide and Cerebral Ischemia

Publisher Summary This chapter reviews the role of nitric oxide (NO) in regulation of cerebral circulation, and as a mechanism of brain injury during experimental stroke and cerebral ischemia. There are a variety of NO-linked mechanisms that protect vascular function during ischemia, but that also pose a threat to neurons, particularly glutamatergic neurons. Pro-oxidant mechanisms involving the chemical interaction of NO and superoxide, and formation of peroxynitrite lead to mitochondrial dysfunction and DNA damage. Such pathology entrains downstream mechanisms linked to further energy depletion. The essential principle to be gleaned is that the overall role of NO in cerebral ischemia is dependent on a dynamic balance between these two states: direct neurotoxicity due to NO overload and vascular defects due to NO deficiency. Similarly, the therapeutic value of inhibiting nitric oxide synthase and NO formation depends on the ability to manipulate this balance effectively.
Data mining track chair's message

The unprecedented growth of electronic data and ever increasing user dependence on electronic data in today's world suggests that data should be regarded as one of the most important assets of the users. Within the last few years Data Mining and Knowledge Discovery technology has established itself as a key technology for enterprises that wish to improve the quality of the results obtained from data analysis, decision support, and the automatic extraction of knowledge from data. The Data Mining Track focuses on the logical and physical design of knowledge discovery systems, particularly, on data classification and clustering, association rules, data mining techniques, data analysis and discovery, and data mining applications.
IEEE 802.16 broadband wireless technology and its application to the military problem space

This paper discusses the emerging IEEE 802.16 broadband wireless technologies and potential applicability to military networks. Interest continues to grow in the military network design community, for leveraging commercial technologies for use in the global information grid (GIG). This is also true in the design of tactical edge networks where there is growing interest in leveraging commercial wireless networking technologies such as the IEEE 802.11 wireless local area network (WLAN) technology family. An emerging commercial capability is in the area of wireless metropolitan area networks (WMA Ns). The emerging IEEE 802.16 broadband wireless access standards aim to provide high data rates over wide geographic ranges. There is also ongoing standardization effort of the eventual IEEE 802.20 mobile broadband wireless solution. This paper provides an overview of IEEE 802.16, then presents a high-level military applicability analysis, identify any technical deficiencies that may require military-specific enhancements. This analysis focuses on the areas of achievable coverage, supportable mobility, quality-of-service (QoS), and security
Face detection using CbCr color model in video

Face Detection is a challenging task due to large variations in pose, illumination, occlusion, scaling and clutter. Face detection is the primary step in Face recognition. The important goal of efficient face detection system is to have negligible misclassification rate. A novel face detection technique using CbCr color model with Haar feature extractor and Adaboost classifier is proposed. The proposed method is compared with Viola Jones and YCbCr color model based face detection techniques. The experimental result shows the proposed method perform better than existing techniques with minimum misclassification.
Modulation by polyelectrolytes of canine cardiac microsomal calcium uptake and the possible relationship to phospholamban.

Abstract Calcium uptake and (Ca2+ + Mg2+)-ATPase activity in canine cardiac microsomes were found to be stimulated by heparin and various other polyanions. Prior treatment of the microsomes with the ionophores alamethicin or A23187 produced no change in the extent of stimulation of the ATPase activity by heparin yet eliminated net calcium uptake. This finding and a lack of change in the stoichiometric ratio of mol of calcium transported/mol of ATP hydrolyzed (calcium:ATP) suggest that the effect of heparin is on the calcium pump rather than on a parallel calcium efflux pathway. Certain polycationic compounds including poly-L-arginine and histone inhibited both cardiac and fast skeletal muscle microsomal calcium uptake and also produced no change in the stoichiometric ratio of calcium to ATP. Several lines of evidence indicate that the polyanionic compounds tested stimulate calcium uptake by interacting with phospholamban, the putative phosphorylatable regulator of the cardiac sarcoplasmic reticulum calcium pump, whereas polycationic compounds appear to interact with the pump. (i) Heparin stimulated calcium uptake to the same extent as protein kinase A or trypsin, whereas prior phosphorylation or tryptic cleavage of phospholamban from the membrane abolished the stimulatory effect of heparin. (ii) Calcium uptake and (Ca2+ + Mg2+)-ATPase activity in fast skeletal muscle microsomes, which lack phospholamban, were unaffected by heparin. (iii) Purified cardiac (Ca2+ + Mg2+)-ATPase activity was no longer stimulated by heparin yet was still inhibited by polycationic compounds. The heparin-induced stimulation of calcium uptake was dependent on the pH and ionic strength of the heparin-containing preincubation medium, hence electrostatic interactions appear to play a significant role in heparin's stimulatory action. The data are consistent with an inhibitory role of the positively charged cytoplasmic domain of phospholamban with respect to calcium pump activity and the relief of the inhibition upon reduction in phospholamban's positive charge by phosphorylation or binding of polyanions.
An Automated, Saccharogenic Method for Determining Serum Amylase Activity

An automated adaptation of the Somogyi saccharogenic determination of serum amylase is described in which conventional AutoAnalyzer modules are used. Adequate sensitivity with short incubation is achieved by incorporating glucose oxidase and catalase in the substrate to destroy serum glucose during incubation. Maltose and other dialyzable oligosaccharides are measured with the alkaline copper-neocuproine reaction. A simultaneous blank run is performed to determine reducing substances other than glucose in serum. Precision studies and correlation with a manual saccharogenic method are presented. The normal range was determined from data for 49 healthy blood donors.
Potent cytotoxins produced by a microbial symbiont protect host larvae from predation

Larvae of the sessile marine invertebrate Bugula neritina (Bryozoa) are protected by an effective chemical defense. From the larvae, we isolated three bryostatin-class macrocyclic polyketides, including the novel bryostatin 20, that deterred feeding by a common planktivorous fish that co-occurs with B. neritina. A unique bacterial symbiont of B. neritina, Endobugula sertula, was hypothesized as the putative source of the bryostatins. We show that: (1) bryostatins are concentrated in B. neritina larvae and protect them against predation by fish; (2) the adults are not defended by bryostatins; and (3) E. sertula produces bryostatins. This study represents the first example from the marine environment of a microbial symbiont producing an anti-predator defense for its host and, in this case, specifically for the host’s larval stage, which is exceptionally vulnerable to predators.
Preparation of Condensed Aromatics by Superacidic Dehydrative Cyclization of Aryl Pinacols and Epoxides1a

Aryl pinacols and epoxides, respectively, are cleanly and in high yield converted via superacidic dehydrative cyclization to the corresponding condensed aromatics. Dehydrative cyclization of benzopinacol (1a), triphenylacetophenone (2), and tetraphenylethylene oxide (9) give 9,10-diphenylphenanthrene (3a) as the major product in acidic media stronger than Ho = −11. Aryl pinacol 12a forms the condensed aromatic 13a as the major product in acidic media stronger than Ho = −13.5. It is proposed that the dehydrative cyclizations to provide aromatics 3a and 13a occurs through dicationic intermediates. Substituted benzopinacols 1f, 1g, and 1j are prepared and give the corresponding phenanthrenes (3f, 3g, and 3j) in high yields. The regiochemistry of the cyclization of substituted benzopinacols is controlled by deactivating substituents on the aryl rings. Aryl pinacols (12a−d) derived from acenaphthenequinone and pinacol 15 also give condensed aromatics (13a−d and 16, repectively) with superacidic triflic acid.
A Distribution Automation Evaluation Using Digital Techniques

Digital computer programs, developed by Public Service Electric and Gas Company (PSE&G), for determination of revenue requirements for economic evaluation of distribution automation are described. Input requirements and typical output results are described for a part of the PSE&G distribution system using four types of financial analysis: continuing plant, short term, year-by-year, and break even. The programs are an integral part of the methodology for the evaluation of approximately 40 distribution automation functions and subfunctions. They provide economic results based on user input of necessary benefit, equipment requirement, economic factor and other distribution system characteristic information. Economic evaluation summaries are described to illustrate development of necessary data for economic evaluation.
Formation of adatom density gratings on a substrate by channeling of an atomic beam through a pulsed-laser standing wave under a completely off-resonant condition.

We show that a transversely uncooled atomic beam can be focused by a microsecond laser standing wave to form adatom density gratings on a substrate with good contrast ratio under a completely off-resonant condition Δω/ω∼1.
Parametric estimation of 3D tubular structures for diffuse optical tomography

We explore the use of diffuse optical tomography (DOT) for the recovery of 3D tubular shapes representing vascular structures in breast tissue. Using a parametric level set method (PaLS) our method incorporates the connectedness of vascular structures in breast tissue to reconstruct shape and absorption values from severely limited data sets. The approach is based on a decomposition of the unknown structure into a series of two dimensional slices. Using a simplified physical model that ignores 3D effects of the complete structure, we develop a novel inter-slice regularization strategy to obtain global regularity. We report on simulated and experimental reconstructions using realistic optical contrasts where our method provides a more accurate estimate compared to an unregularized approach and a pixel based reconstruction.
Leukaemias: a review

Abstract Leukaemia is the most common cancer in children. Leukaemia results from clonal proliferation of stem cells and leads to bone marrow failure. Symptoms at presentation include bruising, bleeding, pallor due to anaemia and infection. The incidence is approximately 5 in 100 000 children. The cause is largely unknown although there is a predisposition in certain congenital conditions such as Fanconi's Anaemia and Down's syndrome and there is some understanding of how genetic mutations may cause leukaemia, but this is not thought to be a single event. The treatment of acute lymphoblastic leukaemia in children older than 1 year is extremely successful and continues to improve. Treatment is tailored according to response (minimal residual disease directed). Multi-agent immunosuppressive chemotherapy, with central nervous system prophylaxis is given over 2–3 years. Acute myeloid leukaemia is five times less common than acute lymphoblastic leukaemia and is treated intensively for 4–5 months and cure rates have remained at 60–70% for two to three decades. Survival has improved due to better supportive care. Chronic myeloid leukaemia is rare and treated with tyrosine kinase inhibitors and as in preleukemic conditions (myelodyplasia) may require allogenic bone marrow transplant.
BEATING BACK The Corporate Attack

I'm proud to be your speaker tonight. I'm also very proud that I've been a member of the Caucus for a New Political Science from the very beginning, and proud also that the caucus is flourishing an...
On the outburst of flare activity of 26 November, 1973

The possible source of a strong 30 hour-long outburst of homologous flare activity, and an unusual growth and brightening of coronal loops in the active region McMath 12628, on the eastern solar hemisphere, on Nov. 1973, as seen from Skylab are analyzed. Prior to that date, not many flares and subflares in the region were associated with radio bursts. However, almost all flares after that date were accompanied by microwaves and type III bursts until the last flare of this kind appeared at 03:52 on the 27th. All the type III bursts were accompanied by type U-bursts, giving evidence for strong closed fields rooted in the site of the radio bursts. It is recorded that U-bursts stopped after 07:18 on Nov. 26, and a change noted is attributed to the occurrence of two two-ribbon flares at the site of the recurrent activity which could have destroyed the U-type favorable situation. A two-ribbon flare, according to Kopp and Pneuman (1976), opens the magnetic field-configuration, and it is therefore suggested that a newly emerging magnetic flux was the source of the complex solar situation. It is suggested that this kind of activity should be studied during the FBS-ALERT periods in 1980-81.
Cortical mechanisms of speech perception in noise.

Purpose The present study examines the brain basis of listening to spoken words in noise, which is a ubiquitous characteristic of communication, with the focus on the dorsal auditory pathway. Metho...
Chemical expansion of nonstoichiometric Pr0.1Ce0.9O2−δ: Correlation with defect equilibrium model

Undoped and acceptor doped cerium dioxide is known to exhibit non-stoichiometry induced chemical expansion at elevated temperatures and reducing environments with impact on the mechanical integrity of solid oxide fuel cells and permeation membranes. In this paper, the chemical expansion of Pr0.1Ce0.9O2−δ is measured and analyzed with respect to its defect equilibria and the chemical coefficient of expansion, analogous to thermal coefficient of expansion, is extracted. The addition of Pr to CeO2 leads to major deviations from stoichiometry, and correspondingly to large chemical expansions, under readily accessible experimental conditions (e.g. in air at elevated temperatures). Pr0.1Ce0.9O2−δ, therefore, serves as a model system for studying chemical expansion in ceria-based solid solutions in order to predict the conditions in which they exhibit suppressed chemical expansion.
Survival after embolization of a complete prosthetic aortic valve to the aortic arch

Partial dehiscence and embolization of poppets, leaflets, and discs are well-known complications of mechanical valve prostheses. Dehiscence with embolization of an entire prosthetic valve is rare. Previous reports of dehiscence and embolization of an entire prosthetic valve are associated with fatality and are the subject of autopsy reports. We report a patient who survived an operation (using cardiopulmonary bypass and total circulatory arrest) to retrieve an embolized prosthetic valve.
Evolution of the technique of congenital diaphragmatic hernia repair on ECMO

With the increase in popularity of delayed repair of congenital diaphragmatic hernia (CDH), many institutions are using extracorporeal membrane oxygenation (ECMO) to stabilize patients preoperatively. This practice has led to controversy regarding whether the repair should be performed while the patient is on ECMO or after decannulation. This report details the authors' experience with repair of CDH on ECMO. Of the 154 high-risk CDH patients treated at Children's Hospital, Boston, MA, since ECMO became available (1984), 97 received ECMO, including 31 who had repair performed while on ECMO. In group I (nine patients), repair was carried out only if the patients were unweanable from ECMO after 7 days. Activated clotting times (ACT) were maintained at 200 to 220 seconds. In group II (22 patients), repair was performed on ECMO electively, before decannulation. ACT were maintained at 180 to 200 seconds. Additionally, all patients in group II received aminocaproic acid before surgery. This was administered continuously for 72 hours postoperatively or until decannulation. Patients in group II had significantly less overall blood loss (P = .02), and lower transfusion requirement (P = .0003) than those in group I. Additionally, four of the nine patients in group I required reexploration because of hemorrhage; this was not required for any patient in group II (P = .005). Although the survival rates differed, this may have been because of a bias in patient selection between the two groups. From these preliminary data, the authors conclude that repair of congenital diaphragmatic hernia on ECMO can be performed safely, with a minimum of hemorrhagic complications.(ABSTRACT TRUNCATED AT 250 WORDS)
A high-speed multichannel neural data acquisition system for IBM PC compatibles

Abstract An inexpensive 32-channel data acquisition system has been constructed for use in acquiring neuroelectric data from a multiple element electrode array. Direct memory access (DMA) techniques allowed a maximum aggregate sampling rate of 652 ksamples/s, or 20.4 ksamples/s on 32 channels. The 8-bit analog-to-digital (A/D) conversion circuitry lies on a single plug-in card installed in an IBM PC-compatible AT&T 6300 Plus personal computer, although the card may be used in an IBM PC with no reduction in sampling performance. Data have been taken from 32 points on the surface of the rat hippocampal slice preparation. Assembly language graphics routines permitted rapid display of raw and processed data. Signal processing routines can be executed and results can be displayed to provide rapid feedback to an experimenter.
Evaluation of a laser-assisted particle sizing/settling velocity determination technique

The use of predictive models for the understanding and management of sediment and contaminant transport generally requires knowledge of particle size and settling velocity. Particle size is often obtained by direct measurements, and the settling velocities are usually predicted using the Stokes' law (or a modification thereof) for single-grained spherical particles. Such measurements and estimates are not satisfactory measures for cohesive sediments, which exist as agglomerated particles called flocs and whose behaviour is significantly different from that of the single-grained particles. Direct measurement of settling velocity and size using optical methods in settling columns has also been employed to improve these predictions; however, the subjectivity in determining which particles are in focus results in unreliable size data. An out-of-focus particle will generally possess a larger size than in reality. This paper evaluates a laser-assisted particle sizing/settling velocity determination technique's ability to eliminate the subjectivity and improve particle-sizing accuracy during settling column experiments. Although the diffraction of light by the translucent standard beads (used for evaluating the technique's accuracy for determining particle size) posed a problem, the results suggest that this technique has potential for assisting researchers to obtain the most accurate settling particle size data possible. Copyright © 2005 John Wiley & Sons, Ltd.
Synthesis of α- and β-Carbon-Linked Serine Analogues of the Pk Trisaccharide

The synthesis of glycopeptide ligands for a range of biomedically relevant carbohydrate-binding proteins is a topic of great importance to the glycobiology community. This task is impeded by the inherent instability of glycosyl linkages to serine/threonine, the normal sites of O-glycosylation in proteins. We have previously developed methodology for the preparation of C-glycosylated serines based on catalytic asymmetric hydrogenation of the corresponding enamide esters with the DuPHOS−Rh+ catalysts. Here we report further development of the methodology in the preparation of the C-glycosyl serine analogue of the Pk trisaccharide (α-Gal(1→4)β-Gal(1→4)β-Glc-CH2-serine); we require these ligands for our continuing investigations of the binding subunit of the shiga-like toxin. Catalytic asymmetric hydrogenation was used to prepare both α- and β-C-glycosides in the R and S serine series. We report here on the tolerance of the DuPHOS catalysts toward acetate, benzoate, and benzyl hydroxyl protecting groups. Addi...
Exodus within an expanding city: The case of Houston's historic African-American communities

Houston, Texas is a city characterized by growth. Since being founded in 1836 the city has continuously expanded, both in land area and population. But within this predominant pattern of growth there are significant exceptions. Particularly poignant is the case of Houston's historic African-American neighborhoods. Over the last 50 years most of the neighborhoods have gradually lost population – a result of land speculation practices, disinvestment and the unintended consequences of desegregation. This article focuses on five historic African-American neighborhoods that form a horseshoe around the eastern half of Houston: Acres Homes; Independence Heights; Settegast; Clinton Park and Sunnyside. In a city that is constantly expanding, most of these communities are shrinking. The narrative histories of the neighborhoods are explored as the foundation for a broader urban design methodology, while also developing urban design strategies that work across scales and processes.
Shock: Mechanisms and therapy

A Unitarian concept of shock has been proposed based upon theoretical physiologic grounds and supported by experimental and clinical data. This concept depicts shock as a defect in effective tissue perfusion, related to a decrease in cardiac output and organ blood flow and an increase in peripheral resistance. Restoration of cardiac output and organ blood flow by maintenance of effective circulating blood volume (central venous pressure, 10 cm. H2O, blood volume, 80 ml./kg. ) in association with digitalization when indicated will be effective in most patients in shock. In the remaining patients in which resistance in the cutaneous and visceral microcirculation remains elevated (pale, cool extremities and reduced urinary output), increased blood flow can be promoted in these areas by use of drugs which decrease vasoconstriction by blocking alpha-receptors ( phenoxybenzamine, phentolamine, chlorpromazine) or decrease resistance to flow by yet unknown means ( massive doses of glucocorticosteroids ) or decrease resistance by beta-receptor stimulation ( isoproterenol ) and consequent dilatation of the microcirculation of the muscles, while also stimulating the same receptors in the heart to increase the force and rate of cardiac contraction. In view of the dismal results obtained by vasopressors, alpha-receptor stimulators such as Levarterenol and Aramine, the use of these substances should be abandoned as the only form of treatment in shock.
Callosal projections of the striate cortex in the neonatal rabbit

Callosal fiber projections of the striate cortex were studied in newborn rabbits using the methods of 1) retrograde transport of horseradish peroxidase (HRP) and 2) orthograde transport of tritiated leucine. Data collected from 6–8 day old animals revealed not only the existence of adult-like commissural fibers in the lateral striate cortex bordering the occipital area, but also an aberrant callosal projection from the medial striate cortex, an area not known to have any commissural fibers in the adult brain of those mammalian species studied.
Alternative Models of Recreational Off-Highway Vehicle Site Demand

A controversial recreation activity is off-highway vehicle use. Off-highway vehicle use is controversial because it is incompatible with most other activities and is extremely hard on natural eco-systems. This study estimates utility theoretic incomplete demand systems for four off-highway vehicle sites. Since two sets of restrictions are equally consistent with utility theory both are imposed and the best fitting restrictions are identified using Voung’s non-nested testing scheme. The demand system is modeled using both Poisson and negative binomial II distributions. Data are provided by a survey conducted at four recreational off-highway vehicle (OHV) sites in western North Carolina.
AN INVESTIGATION OF THE SAMPLING DISTRIBUTIONS OF ITEM DISCRIMINATION INDICES.

The sampling properties of four item discrimination indices (biserialr, Cook's indexB, theU–L 27 per cent index, and DeltaP) were investigated in order to ascertain their sampling properties when small samples drawn from actual test data rather than constructed data were employed. The empirical results indicated that the mean index values approximated the population values and that values of the standard deviations computed from large sample formulas were good approximations to the standard deviations of the observed distributions based on samples of size 120 or less. Goodness of fit tests comparing the observed distributions with the corresponding distribution of the product-moment correlation coefficient based upon a bivariate normal population indicated that this correlational model was inappropriate for the data. The lack of adequate mathematical models for the sampling distributions of item discrimination indices suggests that one should avoid indices whose only real reason for existence was the simplification of computational procedures.
Effect of Fe on the equation of state of mantle silicate perovskite over 1 Mbar

Abstract In order to investigate the effect of Fe on the equation of state (EOS), the volume of the perovskite (Pv) phases, (Mg1−xFex)SiO3, with different Fe contents ( x = 0 , 0.09, 0.15), has been measured at high pressures up to 1 Mbar in an Ar or NaCl medium. A bulk modulus ( K 0 ) ranging between 255 and 261 GPa is obtained when the Au scales consistent with the Pt scale are used and the data are fit to the second order Birch–Murnaghan (BM) equation. When the third order BM equation is used, we obtain K 0 = 250–264 GPa and K 0 ′ = 3.7–4.5, which is consistent with previous low-pressure X-ray diffraction and Brillouin measurements. Within experimental uncertainties (0.5% in volume and 6% in bulk modulus), we do not resolve differences in the EOS between Fe-bearing (up to 15%) and Fe-free Pv to 1 Mbar (2600-km depth in the mantle). This is in contrast with the much larger effect of the Fe spin transition for the EOS of ferropericlase (Fp) reported recently. This is perhaps due to much more diverse states of Fe (e.g., oxidation, coordination, and spin states) in Pv than in Fp.
Experimental Investigation of a Turbulent Compressible Boundary Layer

A turbulent compressible boundary layer in a nominally Mach 4.2 flow was investigated experimentally. Pitot, wall-static pressure, total pressure and temperature measurements were utilized to determine Mach number, temperature, and velocity profiles within the boundary layer. An adverse pressure gradient was observed, resulting in non-uniform flow in the streamwise direction of the test section during development. Alterations were made to the tunnel top and bottom walls to account for the growing boundary layer displacement thickness, resulting in a much improved, uniform Mach number in the freestream and boundary layer. The existence of a slight adverse pressure gradient remained. Flow visualization was conducted via the Schlieren imaging technique. Experimental results were compared against turbulent compressible flow theory and were found to be in excellent agreement, based on an extension of the law-of-the-wall and law-of-the-wake. Velocity profiles and boundary layer thicknesses of the theoretical and experimental results aligned satisfactorily.Copyright © 2009 by ASME
The high-frequency &#928;-criterion for retarded systems

A test for local properness in optimal periodic control of functional differential (including delay differential) equations is proven. If it is satisfied, the performance near an optimal steady state can be improved by controls and trajectories of sufficiently high frequencies.
An approach to computer-aided parametric

Abstract An advanced method for the generation of parametric models in computer-aided design systems is presented. The method uses automatic storage of geometric constraints during the design input, and the support of topology parameters. Together with a record of the construction sequence, important information about the designer's intent is captured, and a more comprehensive description of a design is thereby achieved. A variants processor is used to perform the evaluation of the model shapes according to actual dimensional and structural parameters, based on the stored general model.
Adjuvant chemotherapy for sarcomas and carcinomas.

The use of chemotherapy in small animals with sarcomas and carcinomas is a rapidly growing field of veterinary medicine. Veterinarians considering the use of chemotherapy encounter difficult clinical decisions. One of the major difficulties is the scarcity of published information, such as results of clinical trials, for many tumor types. Another difficulty is the lack of guidelines as to which patients to treat with chemotherapy. This article discusses the principles and applications of chemotherapy in patients with soft tissue tumors and provides a review of the adjuvant chemotherapy protocols available for dogs and cats with sarcomas and carcinomas.
Neuronal influences on glial progenitor cell development

The role of cell-cell interactions in the development of bipotential glial progenitor cells in cultures of rat cerebellum and optic nerve was studied. In the cerebellar cultures, progenitor cells divide slowly and most of their progeny develop into additional progenitor cells. Progenitor cells isolated from postconfluent cultures of cerebellum, however, develop rapidly into oligodendrocytes when grown in a serum-free medium. Factors secreted or shed into the medium by young cerebellar interneurons stimulate optic nerve progenitor cells to divide and promote the survival of progenitor cells. These factors appear to alter the function of the internal clock that regulates the timing of oligodendrocyte differentiation. These results suggest that the neuronal microenvironment can influence the lineage decisions of multipotential glial progenitor cells.
Geographic Routing in Distributed Sensor Systems without Location Information

Geographic routing protocols have been widely used in microsensor networks, however, they cannot directly apply to distributed mobile sensor systems as mobile sensors often do not know their neighbors' exact physical locations. In this paper we consider geographic routing in distributed sensor systems without location information. We address the problem by introducing a lightweight and distributed virtual coordinate assignment protocol. We focus on the effectiveness of routing algorithms for distributed data fusion in the system and provide a detailed analysis of several routing algorithms for a sensor system with group mobility. Our simulation results show that controlled data flows significantly increase the probability of relevant data being fused.
Balance sheet and income statement issues in ARMS

Purpose – The purpose of this research is to analyze possible implications of the economic measures presented in the balance sheet and income statement of the farm firm.Design/methodology/approach – Accounting principles and the users of accounting information are studied. From a review of the Agricultural Resource Management Survey (ARMS) questionnaire, several items are identified that limit ARMS information from fully measuring economic and financial conditions.Findings – ARMS limitations include issues related to asset valuation, income and expense recognition, and extraordinary income reporting. In particular, data limitations on deferred taxes associated with market values exceeding cost, capital leases, prepaid rents, accrued items, Section 179 and accelerated depreciation methods, and extraordinary items may result in understatement of leverage, overstatement of liquidity, and under reporting of year‐to‐year farm income variability measures.Originality/value – By identifying these limitations, cha...
Brief review of city planning in the United States, 1921–1922

Before long it will be easier to make a list of principal cities which are laggard in city planning than to review the accomplishments of those which are active.