cssi/SciSciGPT-SciSciNet huggingface dataset:
Risk for Septic Death in Severe Congenital Neutropenia

We recently reported on the risk for death from sepsis and myelodysplastic syndrome/acute myeloid leukemia (MDS/AML) in patients with severe congenital neutropenia (SCN) on long-term granulocyte-colony stimulating factor (G-CSF) enrolled in the Severe Chronic Neutropenia International Registry (SCNIR). (Rosenberg et al, Blood2006; 107:4628-35, and Brit J Haematol2008; 140:210-3) We found that after ten years a subgroup of SCN patients receiving more than 8 mcg/kg/day of G-CSF who achieved a median absolute neutrophil count (ANC) response of less than 2.188 × 10 9 /L had an estimated risk of dying from sepsis of 14% and a risk of developing MDS/AML of 40%. In order to understand the risk factors for death from sepsis, we reviewed the clinical diagnosis, hematological data, G-CSF treatment, and clinical course of 9 fatalities due to infections, excluding cases with evidence of MDS or AML or occurring after hematopoietic transplantation. The 5 male and 4 female patients’ ages ranges from 1 month to 18.7 years at the time of initiation of G-CSF. All were treated with G-CSF because of severe neutropenia (ANC less that 0.5 × 10 9 /L) and a history of recurrent fevers and infections. The pre G-CSF median ANC for the 9 patients was 0.027 × 10 9 /L and frequent events pre-G-CSF included fevers, severe mouth ulcers, otitis, sinusitis, pneumonia, cellulitis and abscess formation, but bacteremias were infrequent. When started on G-CSF, five patients were clearly poor responders, despite steady upward titration in the G-CSF dose to 22, 45, 65, 68 and 151 mcg/kg/day, respectively. In each of these patients, the ANCs on G-CSF treatment were frequently reported as less than 0.1 × 10 9 /L and the responses were inconsistent and quite variable. The other 4 patients also had inconsistent responses at lower G-CSF doses and the patients’ compliance with treatment was uncertain. Two are known to have had a protracted “off treatment” periods, and the septic death of one patient occurred when off therapy. Deaths were attributed to sepsis (6 cases), pneumonia (2 cases), and meningitis (1 case). These clinical data suggest that death from sepsis in SCN is usually associated with a poor response to G-CSF as reflected by the requirement for dose escalation substantially above the threshold of 8 mcg/kg/day of G-CSF associated with an increased risk of MDS/AML. Inconsistent treatment and discontinuation of treatment also lead to neutropenia and the risk of sepsis. Although impaired microbicidal function may be a contributor to infections in these patients (Donini, et al. Blood109:4716, 2007), the predominant problem is a poor ANC response; the biological basis for poor responses of some SCN patients to G-CSF is still unknown. Based on these data, we recommend careful consideration of a match related or unrelated donor hematopoietic stem cell transplant for all patients not achieving a consistent ANC >1.0 × 10 9 with G-CSF therapy.
Correlation between engineering student leadership practices, personality types, and demographic characteristics

This study examines the degree to which engineering and science students' personality and demographic characteristics are associated with their leadership practices, an area that few studies have explored. The data was from a sample of 70 students attending two institutions (Massachusetts Institute of Technology [MIT] and the Singapore University of Technology and Design [SUTD]) who participated in a 2-month-long leadership program. The participants self-rated their personality types using the Myer-Briggs Type Indicator (MBTI-Form College Edition) and their leadership practices using the Student Leadership Practices Inventory (SLPI). Results from both correlation and multiple regression analyses showed that extraversion is a significant predictor of various types of leadership practices. Gender differences on SLPI leadership practices were found, but there were no unique association between gender and leadership practices after controlling for personality and student institution affiliation. The findings may assist leadership curriculum developers to create leadership programs based on students' personality and/or characteristics.
Have Cigarette Taxes Lost Their Bite? New Estimates of the Relationship between Cigarette Taxes and Youth Smoking

AbstractUsing data from the state and national Youth Risk Behavior Surveys for the period 1991–2005, Carpenter and Cook (2008) find a strong, negative relationship between cigarette taxes and youth smoking. We revisit this relationship using four extra waves of YRBS data (from 2007, 2009, 2011, and 2013). Our results suggest that youths have become much less responsive to cigarette taxes since 2005. In fact, we find little evidence of a negative relationship between cigarette taxes and youth smoking when we restrict our attention to the period 2007–13. We conclude that policy makers interested in reducing youth smoking may have to adopt alternative strategies.
4-Acetyl-3-[2-(eth­oxy­carbon­yl)phen­yl]sydnone

Sydnones, which contain a mesoionic five-membered heterocyclic ring, are more stable if synthesized with an aromatic substutuent at the N3 position. In the title compound {sys­tematic name: 4-acetyl-3-[2-(eth­oxy­carbon­yl)phen­yl]-1,2,3-oxa­diazol-3-ylium-5-olate}, C13H12N2O5, the aromatic substitutent is 2-(eth­oxy­carbon­yl)phenyl. Intra- and inter­molecular hydrogen bonds are observed. The inter­planar angle between the sydnone and benzene rings is 71.94 (8)°. π-ring⋯carbon­yl inter­actions of 3.2038 (16) A arise between the sydnone ring and a symmetry-related C=O group.
Multimarket Contact and Rivalry over Knowledge‐based Resources

Research Summary Research shows that multimarket contact (MMC) reduces rivalry involving downstream activities. Yet, studies showing that MMC can increase the threat of imitation suggest a need to better understand how MMC affects upstream rivalry over knowledge-based resources. In this study, we argue that MMC increases rivalry over knowledge-based resources since the deterrent threat of retaliation that typically leads to mutual forbearance in downstream activities will not be sufficient to restrain firms from protecting their knowledge from imitation in upstream activities. In support of these arguments we find that MMC increases the likelihood that a firm initiates patent litigation against a rival. This study suggests the relationship between MMC and rivalry may depend on the competitive domain and the type of resources over which firms are competing. Managerial Summary How does market overlap or MMC affect rivalry between two competitors? Prior studies have largely found that an increase in market overlap decreases rivalry in less knowledge-intensive context because of the deterrent threat of retaliation. However, in this paper, we argue that an increase in market overlap may not reduce rivalry in more knowledge-intensive context because of heterogeneity in capabilities to protect knowledge. We find that a firm is more likely to initiate patent litigation against a rival as market overlap increases. Our findings suggest that the incentive to protect value across multiple product markets may surpass the motivation to cooperate with rivals and that managers should have a more nuanced view of how market overlap with competitors affects rivalry in more knowledge-intensive contexts.
Rendering a multi-dimensional problem space as an unfolding collaborative inquiry process

This study investigates a group working together in an authentic work setting as they collaboratively render a problem space. We employed an existing data set of a group designing for an European automaker. We used a collaborative inquiry paradigm as a lens for investigation. We analysed the dimensions of the problem space the group renders and the collaborative inquiry practices used. The group rendered a multi-dimensional problem space integrating user experience and organizational considerations for realizing user-centred products. We observed collaborative inquiry practices as four modes of evoking ways of knowing and two modes of building coherence. This study offers a new perspective on design as collaborative inquiry – a social process of building coherence to co-construct valid knowledge.
ErbB4 deletion predisposes to development of metabolic syndrome in mice.

ErbB4, a member of the EGF receptor family, plays a variety of roles in physiological and pathological states. Genetic studies have indicated a link between ErbB4 and type 2 diabetes and obesity, b...
NLRP3 inflammasome independent release of IL-1β by tumor cell lysates stimulated dendritic cells (P2215)

Photodynamic therapy (PDT) has long been known for capable of killing tumor cells and induces anti-tumor immunity. The mechanism of how PDT can enhance anti-tumor response is not clear. We tested the hypothesis that bone marrow derived dendritic cells (BMDCs) activated by PDT-generated tumor cell lysates (PDTTCL) can induce anti-tumor response in Lewis lung carcinoma (LLC), a poorly immunogenic tumor model. We found that LLC tumor growth was retarded by immunization with BMDCs pulsed by PDTTCL. Furthermore, therapeutic effects are observed in preexisting LLC tumor when PDT is combined with PDTTCL treated BMDCs and R848 (TLR7/8 ligand) therapy. This study aims to understand how PDT enhances tumor immunogenicity and provides insight to improve both in situ PDT and PDT vaccine efficacy in combating secondary disease. We found that stimulation of BMDCs with PDTTCL leads to dramatic increase in pro-inflammatory cytokine production, including IL-1β, which plays a critical role in PDT efficacy. Previous studies have shown that production and activation of IL-1β require both TLR signaling and activation of NLRP3 inflammasome. IL-1β production induced by PDTTCL in BMDCs is MyD88 dependent, but the activation of IL-1β appears to be dependent upon elastase and proteinase 3 rather than NLRP3 inflammasome. Together, our findings reveal a novel mechanism of IL-1β activation in BMDCs that does not require NLRP3 inflammasome in response to danger signals from tumor cell lysates.
Linear Dependence Problem

In Chapter 4, we introduced the basic dependence concepts in the context of a perfect nest L of m loops. In this chapter, we consider the mathematical problem of actually computing the dependence of a statement on a statement, caused by a pair of variables. To derive the complete dependence information for L, one needs to find the dependence caused by each pair of variables in the program.
Transcatheter Aortic Valve Replacement: Current Evidence from Large Multicenter Registries

Background: Surgical aortic valve replacement (SAVR) has been considered as a standard of care for treatment of severe symptomatic aortic stenosis (AS). Transcatheter aortic valve replacement (TAVR) has emerged as an attractive alternative for treatment of severe AS in high-risk patients. Despite several large multicenter registries, only one randomized trial (PARTNER) has been published. In the following section, we have summarized the safety and efficacy data from the large multicenter registries.
A Neuro-Musculo-Skeletal Model of Human Standing Combining Muscle-Reflex Control and Virtual Model Control

While neuro-musculo-skeletal models are a common tool in theoretical studies on human gait, they are rarely used for studying human motor control of standing balance. As a result, it is difficult to assess whether proposed control strategies of standing balance can be realized by the human neuromuscular structure. Nor is it clear how the human control of standing balance interacts with that of walking. Motivated by these two shortcomings, we here develop a neuro-musculo-skeletal model of human bipedal standing whose control combines spinal muscle reflexes suggested to be important in walking with a virtual model control mimicking the supraspinal regulation of balance. We show in computer simulations that the model can reproduce several aspects of human standing balance observed in experiments on postural sway. Although control improvements are necessary to capture more aspects, the model may serve as a starting for studying the combined control of standing and walking.
The effects of developmental and current niches on oligodendrocyte precursor dynamics and fate.

Abstract Oligodendrocyte precursor cells (OPCs), whose primary function is to generate myelinating oligodendrocytes, are distributed widely throughout the developing and mature central nervous system. They originate from several defined subdomains in the embryonic germinal zones at different developmental stages and in the adult. While many phenotypic differences have been observed among OPCs in different anatomical regions and among those arising from different germinal zones, we know relatively little about the molecular and cellular mechanisms by which the historical and current niches shape the behavior of oligodendrocyte lineage cells. This minireview will discuss how the behavior of oligodendrocyte lineage cells is influenced by the developmental niches from which subpopulations of OPCs emerge, by the current niches surrounding OPCs in different regions, and in pathological states that cause deviations from the normal density of oligodendrocyte lineage cells and myelin.
A THz Pulse Radiator Based on PIN Diode Reverse Recovery

This paper presents a fully integrated oscillator-less THz pulse radiator based on reverse recovery of a PIN diode implemented using 130-nm SiGe BiCMOS technology. The chip radiates a wideband frequency comb in the THz regime through an on-chip antenna. The spacing between the THz tones can be programmed up to 10.5 GHz by tuning the frequency of the input trigger. The spectrum of the radiated frequency comb is measured from 320 GHz to 1.1 THz with 5.5-GHz spacing between the tones. The Non-Linear Q-Switching Impedance (NLQSI) technique is used for tuning the frequency tones and increasing the stability of the output stage. At a distance of 4 cm from the pulse radiator, the measured SNRs (including the losses) with 1 Hz resolution bandwidth are 51, 40, and 21 dB at 0.6, 0.8, and 1 THz, respectively with a 10-dB line-width of less than 2 Hz. With a 5.5-GHz input trigger, the total power consumption of the chip is 45 mW, with 20 mW consumed by the driver stage.
Universities’ commitment to interdisciplinary research: To what end?

Abstract In recent decades, research universities have been engaged in fostering interdisciplinary research (IDR) in an attempt to support high-impact research that can benefit not only the greater good, but also their bottom line. A common way to enhance “interdisciplinary momentum” and foster IDR is to alter the organizational structure and its basic units: departments and centers. What are the consequences of such structural changes? In short, we do not know. To date there has been no large-scale quantitative assessment of whether and how universities’ commitments to interdisciplinary research are successful in fostering interdisciplinary research. To address this gap within the literature, we collect a wealth of numeric and textual data on 156 research universities nationwide to assess whether structural commitments to IDR influence general research activity (e.g., publications, external grants) as well as interdisciplinary research activity. Our results suggest that structural commitment to IDR does indeed produce some of its intended effects. We found that universities’ commitment to IDR, as manifested in their organizational structure (i.e., the number and interdisciplinary nature of key research units: departments and centers), spurs both scholarly research and NIH grant activity in general, and interdisciplinary research and NIH grant activity in particular. These results suggest that efforts to develop and reorganize academic units are not futile; rather, when value commitments are made tangible via foundational research units like departments and centers, they can have their intended consequences.
Impact of X-Ray Radiation on GaN/AlN MEMS Structure and GaN HEMT Gauge Factor Response

We present electrical measurements of gallium nitride/Aluminum nitride (GaN/AlN) microelectromechanical system (MEMS) beams under the combined influence of strain and X-ray radiation. These results are used to understand the mechanism for the observed piezoresistive gauge factor in GaN devices. Exposure with X-ray radiation decreases the electrical resistance while strongly suppressing the gauge factor. Upon removal of the X-ray, the gauge factor quickly returns to its pre-radiated value, while the electrical resistance remains low for a long period of time. These results suggest that the piezoresistance is mainly due to the generation of piezoelectric fields, which are screened by the mobile charge excited by the X-ray radiation. Preliminary results are also presented for HEMT devices; here, piezoelectric fields shifts the threshold voltage of the transistor resulting in an increase in drain current.
Epicardial Ablation of Ventricular Tachycardia in Arrhythmogenic Right Ventricular Cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited heart muscle disease characterized by progressive fibrofatty replacement of the myocardium, right ventricular enlargement, and malignant ventricular arrhythmias. Ventricular tachycardia (VT) may be seen in all stages of the disease and is associated with sudden cardiac death. In patients who failed anti-arrhythmic medical therapy, catheter ablation has become an attractive therapeutic option to reduce VT burden and implantable cardioverter-defibrillator interventions. In this article, the authors aim to address the overall concepts of epicardial catheter ablation in ARVC, focusing on substrate characterization and ablation strategies.
cis-3, 4’, 5-trimethoxy-3’-aminostilbene is a colchicine site microtubule inhibitor and can be used as a vascular disrupting agent

1413 Targeting tumor vasculature is a new approach in cancer therapy. Colchicine site inhibitors (CSIs) of microtubule such as combretastatin A4 (CA4) and ZD6126 can directly damage tumor endothelium to induce tumor hypoxia and necrosis. However, both CA4 and ZD6126 were shown to have cardiovascular side effects presumably due to injury of normal cardiovascular endothelium. It is therefore important to develop new agents to avoid this major problem. Here we investigate another CSI, cis-3, 4’, 5-trimethoxy-3’-aminostilbene (stilbene 5c), which can effectively induce cell cycle arrest at G2/M phase with an IC50 20 nM. Stilbene 5c does not suppress mouse bone marrow and is tolerated by mice up to 100 mg/kg. Determination of tumor vascular perfusion by dynamic contrast-enhanced (DCE) MRI studies shows that stilbene 5c can selectively suppress tumor perfusion without damaging normal organ perfusion. Histological sections of normal organs from mice treated with stilbene 5c do not reveal any major toxicity in H & E staining. Microvascular density determined by CD34 staining is unchanged in normal organs, but significantly decreased in tumor after stilbene 5c treatment. Mice treated with 5 days of stilbene 5c 25 mg/kg maintain a normal left ventricular ejection fraction, suggesting that stilbene 5c has minimal cardiac toxicity. Pharmacokinetic study reveals that stilbene has a half-life of 1.8 hours in mice. Biodistribution of stilbene 5c is not detectable in heart and lung, but is present at a high level in brain, liver, kidney and tumor at 1 hour after intravenous injection. At 3 hours after injection, the level of stilbene 5c in brain, liver and kidney becomes undetectable, but remains high in tumor, suggesting preferential accumulation of stilbene 5c in tumor. Investigation of the in vivo efficacy of stilbene 5c with ovarian cancer xenograft model shows that stilbene 5c can suppress tumor growth by only 40% compared with control. However, its effect is dramatically improved when combined with anti-angiogenic therapy bevacizumab. We conclude that stilbene 5c is a useful vascular disrupting agent and its combination with bevacizumab could be a promising therapy for cancer.
Impact of baseline conduction abnormalities on outcomes after transcatheter aortic valve replacement with SAPIEN-3

BACKGROUND Baseline conduction abnormalities are known risk factors for permanent pacemaker (PPM) implantation after transcatheter aortic valve replacement (TAVR). We sought to determine the impact of baseline right bundle branch block (RBBB), left bundle branch block (LBBB), left anterior hemiblock (LAHB), first-degree atrioventricular block (AVB) and atrial fibrillation/flutter (AF) on TAVR outcomes. METHODS Consecutive patients who underwent transfemoral TAVR with SAPIEN-3 (S3) were included. We excluded patients with prior PPM, nontransfemoral access or valve-in-valve. RESULTS Among 886 patients, baseline RBBB was seen in 15.9%, LBBB in 6.3%, LAHB in 6.2%, first-degree AVB in 26.3% and AF in 37.5%. The rate of 30-day PPM was 10.1%. Baseline RBBB (OR 4.005; 95% CI 2.386-6.723; p < .001) and first-degree AVB (OR 1.847; 95% CI 1.133-3.009; p = .014) were independent predictors of 30 day PPM. LAHB also resulted in higher PPM rates but only in unadjusted analysis (21.8% vs. 9.4%; p = .003). Baseline LBBB and AF were associated with lower left ventricular ejection fraction (LVEF) at both baseline and 1 year after TAVR. However, Δ LVEF over time were noted to be similar with baseline LBBB (1.8% vs. 1.4%; p = .809) and AF (1.1% vs. 1.7%; p = .458). Moreover, baseline AF was also associated with higher stroke/transient ischemic attack (TIA) at 1 year (4.4% vs. 1.8%; p = .019), 1-year major adverse cardiac and cerebrovascular events (MACCE) (19.5% vs. 13.3%; p = .012) and 2 year mortality (23.5% vs. 15.2%; p = .016). None of the other baseline conduction defects affected long-term mortality or MACCE. CONCLUSION In our S3 TAVR population, baseline RBBB and first-degree AVB predicted higher PPM risk. Prior LBBB and AF were associated with lower LVEF at both baseline and 1 year. Lastly, preexisting AF was associated with higher rates of mortality, stroke/TIA, and MACCE.
Effects of age and sex on primary form and method of cannabis use

Background: While cannabis is the most commonly used illicit substance, few studies have focused on the relationship between sociodemographic factors and preference for primary form or method of ca...
Barriers to AV Bus Acceptance: A National Survey and Research Agenda

Automated Vehicle (AV) buses hold great potential, yet it is not clear if Americans will choose to ride them. Trust and attitudes, often influenced by individual differences, are vital predictors o...
Weighted partition rank and crank moments II. Odd-order moments

The ordinary and symmetrized partition rank and crank moments of higher order have been extensively studied. If we assign a weight $$\sharp (\lambda )$$ for the rank case and a weight $$\omega (\lambda )$$ for the crank case, where $$\sharp (\lambda )$$ and $$\omega (\lambda )$$ , respectively, denote the number of parts in the partition $$\lambda $$ and the number of ones in $$\lambda $$ , it will be shown that such weighted ordinary and symmetrized rank and crank moments of higher order are closely related to the corresponding rank and crank moments when the order is odd.
Are standardized diesel exhaust particles (DEP) representative of ambient particles in air pollution toxicological studies

In this study, we investigated the chemical characteristics of standardized diesel exhaust particles (DEP) and compared them to those of read-world particulate matter (PM) collected in different urban settings to evaluate the extent to which standardized DEPs can represent ambient particles for use in toxicological studies. Standard reference material SRM-2975 was obtained from the National Institute of Standards and Technology (NIST) and was chemically analyzed for the content of elemental carbon (EC), organic carbon (OC), polycyclic aromatic hydrocarbons (PAHs), inorganic ions, and several metals and trace elements. The analysis on the filter-collected DEP sample revealed very high levels of EC (i.e., ~397 ng/μg PM) which were comparable to the OC content (~405 ng/μg PM). This is in contrast with the carbonaceous content in the emitted particles from typical filter-equipped diesel-powered vehicles, in which low levels of EC emissions were observed. Furthermore, the EC mass fraction of the DEP sample did not match the observed levels in the ambient PM of multiple US urban areas, including Los Angeles (8%), Houston (~14%), Pittsburgh (~12%), and New York (~17%). Our results illustrated the lack of several high molecular weight carcinogenic PAHs in the DEP samples, unlike our measurements in major freeways of Los Angeles. Negligible levels of inorganic ions were observed in the sample and the DEP did not contain toxic secondary organic aerosols (SOAs) formed through synchronized reactions in the atmosphere. Lastly, the analysis of redox-active metals and trace elements demonstrated that the levels of many species including vehicle emission tracers (e.g., Ba, Ti, Mn, Fe) on Los Angeles roadways were almost 20 times greater than those in the DEP sample. Based on the abovementioned inconsistencies between the chemical composition of the DEP sample and those of real-world PM measured and recorded in different conditions, we conclude that the standardized DEPs are not suitable representatives of traffic emissions nor typical ambient PM to be used in toxicological studies.
Thoracic outlet syndrome, do women present differently than men?

Abstract Thoracic outlet syndrome (TOS) constitutes a group of diverse conditions that result from compression of the neurovascular bundle—the brachial plexus, subclavian vein, and subclavian artery—as it exits the thoracic outlet. Of the TOS subtypes, neurogenic TOS accounts for more than 95% of cases, venous TOS accounts for 3%–5% of cases, and arterial TOS accounts for 1%–3% of cases. The female to male predominance of TOS has been estimated to be anywhere from a 2:1 to 4:1 ratio. TOS generally arises when there is an environmental stressor in the setting of an anatomic predisposition. A search of the literature reveals little in the way of sex-based differences in symptoms at presentation, and no evidence suggests that women and men present differently for each of the subtypes. However, women are more likely to possess predisposing factors for each of the subtypes, which may partially explain the higher prevalence of women with TOS reported in the literature. Congenital anomalies, such as an anomalous first rib, a cervical rib, a congenital band, or scalene triangle muscle variations, are more common in women. In addition, women are more likely to experience an acquired hypercoagulable state due to oral contraceptive use or pregnancy, which may contribute to vascular (particularly venous) TOS. Women who are competitive athletes are also at elevated risk of developing TOS. This is especially true for women participating in sports such as swimming, softball, volleyball, and water polo due to the repetitive, vigorous overhead movements involved in their sport, which can exacerbate any underlying bony or soft tissue anomaly. Despite the higher prevalence of TOS in women, there is a lack of sex-specific research, and well-controlled, long-term studies of outcomes of TOS patients undergoing the available treatment options with a specific focus on sex differences in presentation and outcomes are seriously needed.
The ageing of bordeaux mixture

Bordeaux mixture (5:5:50) prepared at room temperature (24°C.) contains a high initial concentration of copper in the aqueous phase (4 to 7 mg. copper/litre). On keeping the mixture at 24°C. the copper content of the solution decreases, and in a few days, attains a steady value of 0·47 mg. copper per litre.
The Differential Expression of Low-Threshold Sustained Potassium Current Contributes to the Distinct Firing Patterns in Embryonic Central Vestibular Neurons

The principal cells of the chick tangential nucleus are second-order sensory neurons that participate in the three-neuron vestibulo-ocular and vestibulocollic reflexes. In postnatal animals, second-order vestibular neurons fire repetitively on depolarization. Previous studies have shown that, although this is an important feature for normal reflex function, it is only acquired gradually during embryonic development. Whereas at 13 embryonic days (E13) the principal cells accommodate after firing a single spike, at E16 a few principal cells repetitively can fire multiple action potentials on depolarization. Finally, in the hatchling, the vast majority of principal cells is capable of nonaccommodating firing on depolarization. As a first step in understanding the mechanisms underlying developmental change in excitability of these second-order vestibular neurons, we analyzed the outward potassium currents and their role in accommodation, using brainstem slices at E16. The principal cells exhibited transient and sustained potassium currents, with both of these containing calcium-dependent components. Further, both high- and low-threshold sustained potassium currents have been distinguished. The low-threshold dendrotoxin-sensitive sustained potassium current ( I DS) is associated with principal cells that accommodate and is not expressed in those that fire repetitively. Finally, blocking of I DS transforms accommodating cells into neurons capable of firing trains of action potentials on depolarization. These findings indicate that suppression of I DS during development is sufficient to transform accommodating principal cells into nonaccommodating firing neurons and suggests that developmental regulation of this current is necessary for the establishment of normal vestibular function.
Electron transport in chloroplasts. II. Effect of hydrocarbon solvent extraction on chloroplast membrane structure.

Abstract Heptane extraction and heptane extraction followed by petroleum ether extraction remove up to 93% of plastoquinones A and C from spinach chloroplasts, while removing less than 1% of the chlorophyll. Only minor modification of chloroplast membrane structure is observed after extraction. Osmium-fixed and sectioned chloroplasts show darker staining and thinner cross section after extraction. The surface of the membranes shows fewer globular structures when negatively stained with phosphotungstate.
New concepts in characterization of ischemically injured myocardium by MRI.

New concepts regarding the assessment of ischemic myocardial injuries have been addressed in this Minireview using magnetic resonance imaging (MRI). MRI, with its different techniques, brings not o...
Antibody-Independent Antiviral Function of Memory CD4+ T Cells In Vivo Requires Regulatory Signals from CD8+ Effector T Cells

Previous studies have shown that vaccine-primed CD4+ T cells can mediate accelerated clearance of respiratory virus infection. However, the relative contributions of Ab and CD8+ T cells, and the mechanism of viral clearance, are poorly understood. Here we show that control of a Sendai virus infection by primed CD4+ T cells is mediated through the production of IFN-γ and does not depend on Ab. This effect is critically dependent on CD8+ cells for the expansion of CD4+ T cells in the lymph nodes and the recruitment of memory CD4+ T cells to the lungs. Passive transfer of a CD8+ T cell supernatant into CD8+ T cell-depleted, hemagglutinin-neuraminidase (HN)421–436-immune μMT mice substantially restored the virus-specific memory CD4+ response and enhanced viral control in the lung. Together, the data demonstrate for the first time that in vivo primed CD4+ T cells have the capacity to control a respiratory virus infection in the lung by an Ab-independent mechanism, provided that CD8+ T cell “help” in the form of soluble factor(s) is available during the virus infection. These studies highlight the importance of synergistic interactions between CD4+ and CD8+ T cell subsets in the generation of optimal antiviral immunity.
Central Compartment Neck Dissection for Well-Differentiated Thyroid Cancer

Abstract Introduction: Central compartment neck dissection plays an important role in the appropriate treatment of metastatic papillary thyroid cancer at initial presentation and also in cases of r...
Gravity and the orientation of cell division.

A novel culture system for mammalian cells was used to investigate division orientations in populations of Chinese hamster ovary cells and the influence of gravity on the positioning of division axes. The cells were tethered to adhesive sites, smaller in diameter than a newborn cell, distributed over a nonadhesive substrate positioned vertically. The cells grew and divided while attached to the sites, and the angles and directions of elongation during anaphase, projected in the vertical plane, were found to be random with respect to gravity. However, consecutive divisions of individual cells were generally along the same axis or at 90° to the previous division, with equal probability. Thus, successive divisions were restricted to orthogonal planes, but the choice of plane appeared to be random, unlike the ordered sequence of cleavage orientations seen during early embryo development.
Pithermal effects on control element worth

Abstract The Hurwitz-Roe constant-source control-element theory is extended to a two-group treatment in which the epithermal group is fed from a constant source and in turn feeds the thermal group. It is shown that when there are no epithermal fissions, the absorption area for an element black in both the thermal and epithermal group can be written: C= τ 2 τ 2 −L 2 C HR (τ)+ L 2 L 2 −τ 2 C HR (L) Where τ2 the age from thermal energies to the epithermal cut-off energy, and CHR is the Hurwitz-Roe one-group absorption area as a function of either L2 or τ2. When there are epithermal fissions, the effects of thermal absorptions are reduced by the factor 1− v∑ f 2 ∑ r 2 , ∑ SD 1 ∑ r 1 Where Σf2 is the epithermal fission cross-section, gSr2 is the epithermal removal cross-section, and ΣSD1 and Σr1 are respectively the slowing down and removal cross-section in the group which includes all neutrons of energies above the epithermal groups. This effect of the epithermal fission holds whether the control element is thermally black, or both thermally and epithermally black. It is further shown that the methods outlined can be extended to an arbitrary number of groups. The results of this paper allow a multi-group analysis to be made in terms of the simpler one-group work.
Teratogenicity and developmental toxicity of carbon monoxide in protein-deficient mice

Experiments were carried out to determine the teratogenicity and developmental toxicity of carbon monoxide (CO) in mice fed protein-deficient diets. Pregnant CD-1 mice were fed 27 (control), 16, 8, or 4% protein diets throughout gestation and each group was exposed to 0 (control), 65, 125, 250, or 500 ppm of CO from gestation days 8-18. The CO exposure was continuous except for daily watering, feeding or cage changing. The animals were killed on gestation day 18. Pregnancy status of the dams was examined. Fetuses were examined for gross and skeletal malformations. The percentages of dead or resorbed fetuses and of grossly malformed fetuses per litter were related to the CO exposure levels and inversely related to the dietary protein levels. All levels of CO and 8 or 4% protein diets significantly decreased the fetal weight of normal fetuses. The most commonly seen gross malformations were brachygnathia accompanied by protruding tongue, microstomia, microcephaly, open mouth, or open eyes. Most of the grossly malformed fetuses also had dry, bleached and wrinkled skin. An increased incidence of skull (interparietal or supraoccipital), and jaw (mandible or premaxilla) malformation; wavy ribs and scoliosis of spine; and limb unossifications were observed in the litters of dams fed protein-deficient diet and all levels of CO exposure. Malformed litters in each protein diet were related to CO exposure levels. The data suggest that CO is teratogenic under protein-deficient conditions. Protein deficiency had additive effect on CO teratogenicity and synergistic effect on fetal mortality. Special groups at risk may include cigarette or marijuana smokers and malnourished or undernourished populations.
Connected components of the strata of quadratic differentials over the Teichmüller space

In this paper, we study the connected components of strata of the space of quadratic differentials lying over the Teichmuller space. We use certain general properties of sections of line bundles to put an upper bound on the number of connected components, and a generalized version of the Gauss map as an invariant to put a lower bound on the number of such components. For strata with sufficiently many zeroes of the same order the above lower bound and upper bound coincide.
Donor Inbred Lines for Enhancing the Performance of Single-Cross Sunflower Hybrids

The performance of single-cross hybrids can only be enhanced by adding favorable alleles from donor inbred lines that are not present in either parent. The public inbred lines of cultivated sunflower (Helianthus annuus L.) have not been systematically screened as a source of new favorable alleles for enhancing hybrid performance. The objective of this study was to assess the merits of a sample of public inbred lines as donors of alleles for increasing the seed yield of three hybrids (HA383 × RHA373, HA372 × RHA377, and HA89 × RHA373). The net gain of favorable alleles and several other statistics were estimated from the seed yield means of 14 sterility maintainer (B) lines, four fertility restorer (R) lines, 81 B × B hybrids, and 42 B × R hybrids in field tests at Corvallis, OR and Casselton, ND in 1996 and 1997. HA383 × RHA373, HA372 × RHA377, and HA89 × RHA373 were the highest-yielding hybrids from three heterotic patterns. HA383 × RHA373 had the highest seed yield across years and locations (3285 kg ha -1 ) among all hybrids. The most promising donors for increasing the seed yield of HA383 × RHA373 were HA822, HA851, and HA372. Similarly, the most promising donors for increasing the seed yield of HA372 × RHA377 were HA821 and HA384, and the most promising donors for increasing the seed yield of HA89 × RHA373 were HA383, HA384, and HA821. The elite gene pool of sunflower seems to be a rich source of favorable alleles for increasing hybrid seed yields.
Radiation conductivity for a random void-solid medium with diffusely reflecting surfaces

Abstract A variational principle is formulated for radiant heat transfer through the void spaces and conduction in the solid, of an arbitrary void-solid system with diffusely reflecting surfaces. Variational upper bounds on the effective conductivity of a void-solid suspension are expressed in terms of certain averages characterizing the random geometry. A radiation conductivity upper bound, calculated for a model porous medium generated by randomly placed, overlapping spheres, is compared with well-known results from kinetic theory and radiant heat transport. The variational principle provides a means to obtain useful estimates and upper bounds on the thermal radiation conductivity, that include multiple and anisotropic diffusive scattering in a bed of large particles.
Impression management and the hospitality service encounter: cross-cultural differences.

Abstract Managers, marketers, and employees in the hotel and restaurant industry that are aware of the needs of people from different cultures will be able to better direct their efforts at product development, provide better guest services, and thereby offer a means of developing competitive advantage. This study determined cross-cultural differences in customer perceptions of employee behavior, intentions to return, and tipping between Americans and Asians living in the United States. The study was based on several impression management dimensions (ingratiation, intimidation, self-promotion, exemplification, supplication, and non-verbal behaviors). The results suggest that behaviors associated with ingratiation and exemplification techniques were perceived as being more satisfying for American than Asian respondents. Behaviors demonstrative of intimidation and supplication techniques were perceived as very dissatisfying for Americans.
Finding the Fastest Path in Wireless Networks

The timeliness of packet delivery is an important performance measure in wireless networks, especially when urgent messages need to be transported through a network. This paper investigates the fastest packet transportation in light-loaded wireless networks. We show that the end-to-end packet delay depends largely on the locations of the relay nodes that forward the packet and there exists a shortest-delay path theoretically. We also propose a routing algorithm to locate a fast relay path in actual networks to achieve the near-shortest packet delay.
Microwave sintering of boron carbide

Boron carbide has been sintered to 95% of theoretical density in less than 12 minutes without the use of sintering aides by heating to 2000°C with 2.45 GHz microwave radiation. An average grain size of about 20 μm resulted. Twins and microcracking were present in the microstructure. Energy usage for microwave sintering was found to be 18% less than for inductive hot-pressing.
H2S removal with ZnO during fuel processing for PEM fuel cell applications

Abstract The efficacy of using ZnO as an absorber for the removal of H2S from small fuel processor steam reformate streams was examined. At temperatures below 300 °C, H2S can in principle be reduced to below 100 ppbv, required for safe operation of PEM fuel cells. The ZnO adsorbent performed predictably based on ZnO-H2S-ZnS-H2O equilibria with steam, hydrogen, and CO2 in the feed. However, addition of CO even at levels as low as 1 vol% drastically lowered the sulfur removal capability of the ZnO. This is consistent with the formation of COS by the reaction H2S + CO = H2 + COS. ZnO is not an efficient absorber for COS. Indirect evidence is also provided for the formation of COS via the reaction CO2 + H2S = COS + H2O, which can occur in special cases when CO2 is present but neither H2O nor CO is present in the feed. The potential for COS formation compromises the ability of ZnO to deliver very low sulfur concentration reformate.
996 LYMPHOID DEVELOPMENT OF FETAL INTESTINAL TRANSPLANTS IN SYNGENEIC RATS

Because small intestines are inaccessible to experimental manipulation, the development of mucosal immunity has been difficult to study. We thus conducted a longitudinal study of fetal intestinal transplants in syngeneic Fisher strain rats. Fetal jejunum and ileum (6-8 cm) were transplanted to dorsal fascia of syngeneic adults. Three weeks later the intestinal length was >2.5 cm. in 70% of recipients. Each week, part of each transplant was resected and evaluated for IgA containing plasma cells ClgA P.C.). Peyer's patches, lymphoid follicles, and lacteals were present. The number of intraepithelial lymphocytes (I.E.L.) and IgA P.C. were: Following secondary immunization of the transplants with cholera toxin, the number of specific antibody containing cells (ACC) in intestinal transplants and in situ intestines increased ten and five fold, respectively. In contrast, no ACC developed in the transplants after intraperitoneal immunization. Thus, this study suggests that fetal intestinal transplants behave as part of the mucosal immune system. Further study of this model may provide insight into the development of mucosal immunity.
Polymer structure and gas permeation. I. Thermodynamic interpretation of permeation

A thermodynamic interpretation of the permeation process of gas transport through polymeric membranes is proposed. The mechanism used does not require the usual P = DS relationship. The dependence of gas permeability upon the crystallinity, strain, etc. is presented, and a method for obtaining values for the entropy of crystallization is suggested. Literature data have been correlated by this approach and values for the entropy of crystallization of polyethylene, polyethylene terephthalate, and nylon 610 were derived.
A classical model for stochastic multiphoton absorption processes of anharmonic molecules

Abstract Classical power absorption of an anharmonic molecule in intense infrared radiation is calculated. A generalized damping factor and an effective random phase are introduced for the stochastic field-molecule interaction. It is shown that the over-all broadening of the power response has a fundamental lorentzian, no matter what the source of line broadening is. Excellent agreement with the quantum-mechanical results is obtained by quantizing the classical model.
Generation of charged liquid cluster beam of liquid-mix precursors and application to nanostructured materials

Abstract A novel technique for generating a charged liquid cluster beam (CLCB) of liquid-mix precursors has been developed by using flow-limited electrostatic spraying facilitated by field-injection charging. The technique is inherently capable of generating charged nanodrops of controlled size, chemical composition, and stoichiometry, which are very susceptible to heat treatment and pyrolysis. It is, therefore, possible to convert a CLCB spray into solid nanoparticles by exposing it to a heated carrier gas. Deposition of high-quality thin films or nanocrystallites on a substrate is also possible by directing the CLCB spray onto a heated substrate. Since all of the nanodrops in the CLCB spray are charged, an electromagnetic lens can be employed to conveniently control their trajectories for direct writing of micropatterns. This paper briefly describes the physical processes underlying the CLCB technique, the apparatus, and the preliminary results illustrating the application potential of the CLCB technique.
In vitro RNA synthesis from unique pieces of simian virus 40 DNA produced by a restriction endonuclease.

Abstract SV40 virus DNA has been cleaved into large, unique fragments by the Hemophilus influenzae restriction endonuclease. Microgram quantities of the larger fragments have been separated by electrophoresis in a simple Tris-HCl buffer on polyacrylamide-agarose gels. Individual fragments are removed from the gel and used as a template for bacterial RNA polymerase. Some of the synthetic RNA which is produced hybridizes to denatured SV40 DNA and appears, by competition-hybridization experiments, to be similar to in vivo RNA extracted from SV40 virus-infected cells. The technique presented is intended to provide a general scheme for restricted in vitro RNA synthesis of viral DNA molecules.