cssi/SciSciGPT-SciSciNet huggingface dataset:
County-Level Estimates of Excess Mortality associated with COVID-19 in the United States

Abstract The coronavirus disease 2019 (COVID-19) pandemic in the US has been largely monitored on the basis of death certificates containing reference to COVID-19. However, prior analyses reveal that a significant fraction of excess deaths associated with the pandemic were not directly assigned to COVID-19 on the death certificate. The percent of excess deaths not assigned to COVID-19 is also known to vary across US states. However, few studies to date provide information on patterns of excess mortality and excess deaths not assigned to COVID-19 for US counties, despite the importance of this information for health policy and planning. In the present study, we develop and validate a generalized linear model of expected mortality in 2020 based on historical trends in deaths by county of residence between 2011 and 2019. We use the results of the model to generate county estimates of excess mortality and excess deaths not assigned to COVID-19 for each county in the US along with bootstrapped prediction intervals. Overall, in counties that had statistically significant increases in excess mortality, the proportion of excess deaths assigned to COVID-19 was 82%, meaning that 18% of excess deaths were not assigned to COVID-19. The proportion assigned to COVID-19 was lower in the South (77%) and West (78%) as compared to counties in the Midwest (82%) and Northeast (94%). Across US Census Divisions, the proportion was especially low in the East South Central Division (68%). Rural counties across all divisions (68%) reported lower proportions of excess deaths assigned to COVID-19 than urban areas (84%). For instance, in the Pacific Division, less than half of excess deaths were assigned to COVID-19 in nonmetro areas. In contrast, the New England Census Division stood out as the only division where directly assigned COVID-19 deaths actually exceeded excess deaths, meaning there were 1.22 directly assigned COVID-19 deaths for every 1 excess death. However, this finding did not extend to nonmetro areas within New England where less than three-quarters of excess deaths were assigned to COVID-19. The finding that metro areas in New England reported higher direct COVID-19 mortality than excess mortality suggests that reductions in mortality from other causes of death may have occurred in these areas, at least among some populations. Across individual counties, the percentage of excess deaths not assigned to COVID-19 varied substantially, with some counties’ direct COVID-19 tallies capturing only a small fraction of total excess deaths, whereas in other counties the direct COVID-19 death rate far exceeded the number of estimated excess deaths. Taken together, our results suggest that regional inequalities in the mortality burden associated with COVID-19 are not fully revealed by data at the state level and that consideration of excess deaths across US counties is critical for a full accounting of the disparate regional effects of the pandemic on US mortality.
An efficient optimization framework for tracking multiple quality attributes in supply chains of perishable products

Abstract Improved supply chain optimization strategies can play a major role in addressing global food security and safety in years to come. In particular, tighter safety regulations, changing consumer quality requirements and more stringent market competition call upon integrated supply chain decision-making frameworks that explicitly consider product quality control. This effort requires metrics of quality that accurately reflect product physico-chemical properties, as well as consumer purchasing preferences. However, a critical challenge linked to embedding the complex dynamics of the evolution of product quality in time within supply chain models is the large-scale nature of the ensuing optimization problems, which are computationally intractable even for moderate-size, single-item systems. In the present work, we introduce a computationally efficient optimal production and distribution planning framework for perishable products having multiple quality attributes that evolve in time as a function of environmental conditions during shipment and storage. We also propose a model reduction strategy and a decomposition framework that enhance the scalability of our approach. We perform extensive numerical simulations using different network instances to validate our theoretical findings, as well as to demonstrate the advantages of the proposed supply chain management scheme.
The Role of Virtual Physical Therapy in a Post Pandemic World - Pearls, Pitfalls, Challenges, and Adaptations.

Objective To keep patients healthy and safe during the pandemic, payers and the federal government temporarily relaxed restrictions, expanded the eligible provider list for providing telehealth services, and developed a reimbursement structure. Physical therapists were uniquely challenged during the pandemic, requiring a reassessment of techniques and strategies in order to best support patients. The purpose of this case report is to describe a musculoskeletal institution's experience with implementing telehealth physical therapy. Methods Previous telehealth experience enabled the infrastructure of a wide-scale adoption across institutions to respond to the COVID-19 pandemic. However, to fill in training gaps for Hospital for Special Surgery (HSS) outpatient physical therapists, HSS Rehabilitation developed a robust education and implementation program. This training was influenced by clinician and patient surveys as well as the development of a published HSS Rehabilitation telehealth guide. Prior to performing telehealth physical therapist visits, clinicians were required to complete all training material to ensure comfortability and confidence. Results The adoption of telehealth among clinicians was born out of necessaity; however, the speed with which HSS Rehabilitation pivoted was critical to avoid lapses in care. In a 4-week period after the New York City shelter in-place orders, 173 therapists were trained and performing virtual visits. HSS Rehabilitation determined telehealth physical therapy had quicker access to care, similar patient satisifaction, and increased geographical outreach compared with in-person care. Conclusion The transition to telehealth physical therapy included a multi-step process that provided clinician training, established protocols and guidelines, and obtained a better understanding of the patient experience. Telehealth physical therapy has shown early benefits such as improving patient access to care and better continuity of care for traveling patients. Even after the current public health emergency, there is a place for high-value telehealth physical therapy in caring for patients with musculoskeletal conditions.
Fraction representations and robust stabilization of nonlinear systems

The purpose of this note is to provide a survey of the theory of fraction representation and robust stabilization of nonlinear systems developed by the author over the last few years. The note contains an exposition of the main results obtained so far and some examples, but no proofs are included. The results are all explicit and implementable.
Abstract 20455: Comparing the Efficacy of Contractile and Pre-Contractile Cardiomyocytes in Restoring the Function of the Injured Myocardium

BACKGROUND: Cell therapy has shown to promote the repair of injured cardiac muscle post-myocardial infarction (MI). However, transplantation of human embryonic stem cell (hESC)-derived cardiomyocytes (hCMs) has not demonstrated consistent functional restoration of the injured myocardium. This may be explained by their reduced plasticity and engraftment potential due to their developmentally differentiated state. HYPOTHESIS: Pre-contractile hCMs (pre-hCMs) will provide significant and sustained restoration of the injured myocardium compared to the contractile hCMs. METHODS & RESULTS: H7 hESCs were differentiated through small molecule manipulation of the Wnt signaling pathway in cardiac development. Cells were cultured for 2 days with 6 uM CHIR99021, a Wnt activator, followed by another 2 days with 5 uM IWR-1, a Wnt inhibitor. Spontaneous contractility was typically observed around 10 days after initial exposure. For the purpose of analysis, hCMs were harvested at day 35 and pre-hCMs were harvested at day 8. Flow cytometry revealed that 76.8 ± 16.2% of CMs expressed cardiac troponin T whereas less than 5% of pre-hCMs expressed this same protein (p < 0.05). RT-PCR was also performed to determine the genetic profile of these populations. Relative to the undifferentiated hESCs, both groups displayed significant down-regulation of pluripotency genes, but compared to hCMs, pre-hCMs were found to have higher levels of mesodermal and early cardiac genes and lower levels of late cardiac genes. SCID mice with permanent LAD ligation had hCMs, pre-hCMs, or PBS injected into the peri-infarct zone and underwent MRI to record changes in EF. Baseline EF was 44.1 ± 3.8% but 2 weeks after surgery the pre-hCM mice were up to 47.5 ± 1.1%* while the hCM mice had dropped to 28.9% and the PBS mice had fallen even further to 16.1 ± 8.1%. This trend was maintained at week 4: pre-hCM 45.0%*, hCM 29.9 ± 4.3%, and PBS 6.2%. [* p < 0.05 vs. hCM and PBS] CONCLUSIONS: We demonstrate that the mesodermal/early cardiac developmental state of pre-hCMs compared to hCMs provides sustained and significant improvement in LVEF. While the exact mechanism is not known, the non-contractile cells may enhance their engraftment by the ability to align their orientation with the existing myocardium.
A generalized Petri net state equation

T. Murata's (see IEEE Trans. Autom. Control, vol.AC-22, no.3, p.202-6, June 1977) state equation for standard Petri nets is extended to other continuous time systems. The crucial step in this development is to consider conceptually the marking's entries of a Petri net to be nonnegative real numbers rather than integers. This will allow the introduction of calculus into the state equation, which is a differential rather than linear equation. Murata's state equation is a finite difference approximation to this equation. The proposed state equation will be a stochastic differential equation if random time is associated with each transition. >
Clinical decision-support systems

If you ask people what the phrase “computers in medicine” means, they often describe a computer program that helps physicians to make diagnoses. Although computers play numerous important medical roles, from the earliest days of computing people have recognized that computers might support physicians by helping these people to sift through the vast collection of possible diseases and symptoms. This idea has been echoed in futuristic works of science fiction. In Star Trek, for example, medical workers routinely point devices at injured crew members to determine instantly what is the problem and how serious is the damage. The prevalence of such expectations, coupled with a general societal concern about the influence of computers on interpersonal relationships and on job security, has naturally raised questions among health workers. Just what can computers do today to support clinical decision-making? How soon will diagnostic tools be generally available? How good will they be? What will their effects be on the practice of medicine, on medical education, and on relationships among colleagues or between physicians and patients?
Lack of p53 augments anti-tumor functions of cytolytic T cells (VAC11P.1005)

Various effects of altered p53 expression are known with reference to uncontrolled cell proliferation, senescence and cell death. Loss of p53 also induces spontaneous inflammatory lesion and Treg deficiency. Only minor differences in proliferation, apoptosis, and maintenance of ‘non-self’ viral antigen specific T cells have been previously reported. However, the role of p53 in controlling T cell response to ‘self’ tumor epitope has not been comprehensively investigated. The h3T TCR transgenic mice with human tyrosinase epitope reactive T cells were thus developed on p53 deficient background and in vitro/in vivo analysis performed. Our data shows that TCR transgenic T cells from p53 KO mouse in comparison to wild type T cells exhibited increased proliferation, higher IFN-g secretion, enhanced cytolytic capacity, higher expression of stemness gene signature and were less susceptible to cell death upon restimulation with the cognate antigen. The effect of p53 inhibition on increased glycolytic effector functions was mirrored when treating human TCR transduced T cells with p53 inhibitor pifithrin-µ. Finally, the increase in effector function after p53 inhibition also correlated to the improved control of subcutaneously established murine melanoma after adoptive transfer of T cells. Thus, our data highlights the key role of p53 in metabolically regulating the tumor epitope specific T cell response and has potential translational significance in adoptive T cell therapy.
McDonald's Paradoxical Legacy: State Restrictions on Non-Citizens' Gun Rights

Relying on the Supreme Court's recent decisions in District of Columbia v. Heller and McDonald v. City of Chicago, the United States District Court for the District of Massachusetts recently ruled that the Second Amendment's individual right to possess a gun for self-defense, which the Supreme Court found in Heller and incorporated against the states in McDonald, protected a lawful permanent resident's right to bear arms and that the Massachusetts statutory scheme with respect to non-citizens violated that right. The district court found that the Second Amendment applies to non-citizens because the court read McDonald as incorporating the Second Amendment through the Due Process Clause, which protects against states infringing on the rights of "persons." However, the court erred when it ignored the voting paradox within the McDonald decision. This Essay attempts to resolve McDonald's paradox in the context of non-citizens by applying a modification of the familiar rule for dealing with fragmented Supreme Court opinions. Under that modified rule, there is no basis for finding that the Second Amendment, applied to the states through the Fourteenth Amendment, protects non-citizens from gun restrictions. There may be other reasons to find that states cannot restrict non-citizens from owning or possessing firearms, but based on Supreme Court precedent, incorporation of a fundamental right is not one of them.
Qualitative dynamics and fusion

Fusion of qualitative data with quantitative sensory inputs in the realm of tracking and maneuver detection is addressed. The main problem that is addressed is the nonsoundness of reasoning about maneuvers when using the maneuver-box approach. Instead, an approach based on critical hypersurfaces separating nonmaneuver from maneuver states is proposed. >
Standard Errors of Equating

Two general sources of error in estimating equating relationships are present whenever equating is conducted using data from an equating study: random error and systematic error. Random equating error is present when the scores of examinees who are considered to be samples from a population or populations of examinees are used to estimate equating relationships. When only random equating error is involved in estimating equating relationships, the estimated equating relationship differs from the equating relationship in the population because data were collected from a sample, rather than from the whole population. If the whole population were available, then no random equating error would be present. Thus, the amount of random error in estimating equating relationships becomes negligible as the sample size increases.
Requirement for the expression of poly(ADP-ribose) polymerase during the early stages of differentiation of 3T3-L1 preadipocytes, as studied by antisense RNA induction.

Poly(ADP-ribose) polymerase (PADPRP) is biologically significant in the rejoining of DNA strand breaks. Post confluent cultures of 3T3-L1 preadipocytes showed marked increases in PADPRP protein and activity when the cells were induced to differentiate into adipocytes. When this increase in PADPRP expression was prevented in stably transfected 3T3-L1 cells by induction of PADPRP antisense RNA synthesis, the cells did not differentiate nor undergo the two or three rounds of DNA replication that are required for initiation of the differentiation process. 3T3-Ll cells expressing PADPRP antisense RNA under differentiation conditions were easily detached from plates and in some cases eventually died. When newly expressed PADPRP protein and DNA synthesis was assessed in cells at zero time or at 24 h after induction of differentiation by incorporation of bromodeoxyuridine or [3H]thymidine into DNA, significant incorporation was shown to occur in control cells after 24 h, but not in antisense cells. Furthermore, during the first 24 h, the co-immunoprecipitation of PADPRP and DNA polymerase α was observed in control cells, whereas no such complex formation was noted in the induced antisense cells, nor in uninduced control cells.
K-Anonymization as Spatial Indexing: Toward Scalable and Incremental Anonymization

In this paper, we introduce a novel approach to k-anonymization by making a new observation of a strikingly similar parallel between database indexing and k-anonymity. In general, however, the table to be published may contain more than one quasi-identifier attribute, so rather than use B+-trees, we suggest multidimensional spatial indexing as the basis for anonymization. We take a brief detour to discuss a measure for the quality of an anonymization algorithm.
Police Education, Experience, and the Use of Force

Police researchers have devoted a considerable amount of empirical attention to testing the impact college education has on police performance. The counterargument to the education debate is that experience, in learning the police craft, is what contributes to differences in performance. The current study adds to both lines of research by examining the impact of education and experience on one of the core features of the police role: the use of coercion. The findings indicate that varying levels of education and experience are related to differences in the use of coercion in encounters with citizens. Encounters involving officers with any college education result in significantly less verbal force compared to those with a high school education. However, only those encounters involving officers with a 4-year degree result in significantly less physical force. Finally, encounters involving officers with greater experience result in less verbal and physical force.
Lasers without inversion in quantum well intersubband transitions

We propose a new class of intersubband lasers and amplifiers that achieve net gain without population inversion. The laser scheme is based on a unipolar semiconductor double quantum- well structure where gain occurs at a transition between conduction band subbands. In order to achieve net gain without inversion, we utilize Fano-type interferences. The semiconductor laser scheme that we are considering is analogous to the atomic lambda system that has been extensively analyzed in the context of electromagnetically induced transparency and lasing without inversion. A coherent coupling field however, is not required in the present scheme. The electronic coherence necessary for Fano-type interferences is established by resonant tunneling. For nonlinear optics applications, the asymmetry of the structure allows for (chi) (2) processes and therefore higher conversion efficiency or parametric gain.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Reliability of and Intercorrelations Between Cattell's IPAT Anxiety and Neuroticism Scales

(1966). Reliability of and Intercorrelations Between Cattell's IPAT Anxiety and Neuroticism Scales. The Journal of General Psychology: Vol. 75, No. 1, pp. 1-7.
An estimate of the outgassing of space payloads and its gaseous influence on the environment

The outgassing of several space systems—including spacecraft instruments, spacecraft, the Shuttle bay, and a spent solid motor—is described. The outgassing was obtained from measurements in large vacuum chambers or, as for the Shuttle, implied from discrete measurements of the bay environment in orbit. The outgassing is expressed in terms of nitrogen, and described as a function of time. Its chemical composition obtained from massspectrometer measurements is also reported for some systems. The data are intended to provide a basis for estimating the following parameters of importance for instruments and payloads that have similar functions, weights, volumes, and designs: internal pressures, outgassing contribution to the environment, selfcontamination, and contamination to nearby systems. In the future, with the full utilization of the Shuttle, there may be a need to put a payload in orbit that has not been tested in a vacuum chamber or extensively analyzed for outgassing. In such instances, an estimate of outgassing behavior in orbit may be provided on the basis of the data reported herein. In the following, the weights, volumes, and some of the scientific functions of the instruments for which outgassing data are available are indicated. Also, a brief description of the methods used to obtain the data is provided. General indications on how to use the data to obtain the internal pressure vs time for a payload, its self-contamination, the gaseous flow in its vicinity, the column densities in its field of view, and other environmental parameters are provided.
Dynamic Clamp Analysis of Synaptic Integration in Sympathetic Ganglia.

Advances in modern neuroscience require the identification of principles that connect different levels of experimental analysis, from molecular mechanisms to explanations of cellular functions, then to circuits, and, ultimately, to systems and behavior. Here, we examine how synaptic organization of the sympathetic ganglia may enable them to function as use-dependent amplifiers of preganglionic activity and how the gain of this amplification may be modulated by metabotropic signaling mechanisms. The approach combines a general computational model of ganglionic integration together with experimental tests of the model using the dynamic clamp method. In these experiments, we recorded intracellularly from dissociated bullfrog sympathetic neurons and then mimicked physiological synapses with virtual computer-generated synapses. It, thus, became possible to analyze the synaptic gain by recording cellular responses to complex patterns of synaptic activity that normally arise in vivo from convergent nicotinic and muscarinic synapses. The results of these studies are significant because they illustrate how gain generated through ganglionic integration may contribute to the feedback control of important autonomic behaviors, in particular to the control of the blood pressure. We dedicate this paper to the memory of Professor Vladimir Skok, whose rich legacy in synaptic physiology helped to establish the modern paradigm for connecting multiple levels of analysis in studies of the nervous system.
Contrasting urban and rural lifestyles of memory CD8+ T cells

Abstract Memory CD8 + T cells in lymphoid tissue exhibit an unexpectedly high apoptosis rate, while memory cells located in several nonlymphoid tissues do not. This may be because the lymphoid CD8 + memory T cell repertoire is being continuously updated, while the tissue repertoire is more stable.
Reactive scattering from solid surfaces: Treatment of lock-in detector signals from modulated molecular beams

Abstract The lock-in detector signals for modulated molecular beams reactively scattered from solid surfaces were investigated. For a simple first order adsorption-desorption for the surface reaction it was found that the phase lag for the product signal rapidly shifts to lower values in that region of the surface temperature at which the product desorption rate “resonates” with the beam modulation rate. At higher chopping frequencies the phase correction for the dispersion of the beam packet becomes significant. For the reaction rate constants and the wide range of modulation frequencies investigated, the logarithm of the product signal plotted against the reciprocal of the surface temperature is linear with a slope proportional to the product desorption energy without correction of signal intensity for beam dispersion.
Developing a Five-year Maintenance and Rehabilitation (M&R) Plan for HMA and Concrete Pavement Networks

In the face of increased demand and exposure to environmental effects, the condition of road pavements continues to decline while resources for their preservation remain limited. Thus, the task of managing pavements has to be done systematically and objectively. This paper outlines the steps involved in developing a multi-year pavement Maintenance and Rehabilitation (MR (2) network inventory and database development; (3) identification of pavement sections requiring MR (3) needs analysis; and (4) impact analysis. As a case study, the project was performed on the road network inside the Texas A&M University campus that consists of 13.95 miles of roadway, 80% and 20% of which are concrete and HMA pavements respectively. Condition assessment was done according to ASTM D 6433-07 and using the Pavement Condition Index (PCI) as indicator of pavement performance. Data collected were then entered into a database which also contains information on traffic and roadway characteristics. PCI threshold values were established to identify sections that are in need of M&R and the most cost- effective treatment based on long-term performance benefit and life-cycle cost was proposed for each project. Candidate projects were then prioritized by ranking based on benefit-cost analysis. The needs estimate provides meaningful information on the total amount of budget required to correct all deficiencies in the network. Finally, the impact analysis is used to determine the impact of a reduced budget on network condition as well as the amount of backlog that needs to be addressed.
β-Arrestin-mediated Signaling Regulates Protein Synthesis *

Seven transmembrane receptors (7TMRs) exert strong regulatory influences on virtually all physiological processes. Although it is historically assumed that heterotrimeric G proteins mediate these actions, there is a newer appreciation that β-arrestins, originally thought only to desensitize G protein signaling, also serve as independent receptor signal transducers. Recently, we found that activation of ERK1/2 by the angiotensin receptor occurs via both of these distinct pathways. In this work, we explore the physiological consequences of β-arrestin ERK1/2 signaling and delineate a pathway that regulates mRNA translation and protein synthesis via Mnk1, a protein that both physically interacts with and is activated by β-arrestins. We show that β-arrestin-dependent activation of ERK1/2, Mnk1, and eIF4E are responsible for increasing translation rates in both human embryonic kidney 293 and rat vascular smooth muscle cells. This novel demonstration that β-arrestins regulate protein synthesis reveals that the spectrum of β-arrestin-mediated signaling events is broader than previously imagined.
No evidence of exogenous origin for the abnormal glutathione redox state in schizophrenia.

Abstract Schizophrenia has been associated with low glutathione (GSH), one of the most important substrates for natural defense against oxidative stress. This abnormality is often attributed to genetic or other pathological causes. However, low GSH in schizophrenia could also be due to insufficient antioxidant consumption or other exogenous factors. We evaluated GSH in relation to diet, smoking, and medication status in schizophrenia patients. We recruited 54 participants (29 schizophrenia patients and 25 normal controls). The Antioxidant Dietary Source Questions was used to estimate the total antioxidant capacity (TAC) from participants' diet. GSH and the oxidized form of glutathione (GSSG) were assayed. We found that GSH was significantly lower (p
Magnetic Susceptibilities and Nuclear Magnetic Resonance Measurements in V-Fe Alloys

Magnetic susceptibilities and nuclear magnetic resonance measurements have been made on V-Fe alloys up to 34 at.% Fe in V. The composition and temperature dependence of the susceptibilities and of the NMR linewidth of ${\mathrm{V}}^{51}$ suggests the appearance of magnetic moments at about 23 at.% Fe. The Knight shifts of ${\mathrm{V}}^{51}$ in the nonmagnetic portion of this alloy system are discussed in terms of the contributions from the Fermi contact term, $\mathrm{sd}$ exchange, and induced orbital paramagnetism.
Ab initio calculations of strain fields and failure patterns in silicon nitride intergranular glassy films

Theoretical experiments were performed on silicon nitride intergranular glassy film (IGF) models subjected to tensile loading using an accurate ab initio method. The results were used to investigate the strain fields within IGF models. The Green–Lagrange strain fields were calculated from the displacement gradients of the IGF models under various loads. Significant deviations from the first-order Cauchy–Born rule were observed for IGF models even under small load. The strain fields were also analysed to understand atomic-scale mechanisms that lead to intergranular and intragranular failures.
A comparison of ultrasound and magnetic resonance imaging shows that kidney length predicts chronic kidney disease in autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD) is marked by gradual renal cyst and kidney enlargement and ultimately renal failure. Magnetic resonance–based, height-adjusted total kidney volume (htTKV) over 600 cc/m predicts the development of CKD stage 3 within 8 years in the Consortium for Radiologic Imaging in Polycystic Kidney Disease cohort. Here we compared simultaneous ultrasound and magnetic resonance imaging to determine whether ultrasound and kidney length (KL) predict future CKD stage 3 over longer periods of follow-up. A total of 241 ADPKD patients, 15–46 years, with creatinine clearance of 70 ml/min and above had iothalamate clearance, magnetic resonance, and ultrasound evaluations. Participants underwent an average of five repeat clearance measurements over a mean follow-up of 9.3 years. Ultrasound and magnetic resonance-based TKV and KL were compared using Bland–Altman plots and intraclass correlations. Each measure was tested to predict future CKD stage 3. Relatively strong intraclass correlations between ultrasound and magnetic resonance were found for both htTKV and KL (0.81 and 0.85, respectively). Ultrasound and magnetic resonance-based htTKV and KL predicted future CKD stage 3 similarly (AUC of 0.87, 0.88, 0.87, and 0.88, respectively). An ultrasound kidney length over 16.5 cm and htTKV over 650 ml/min had the best cut point for predicting the development of CKD stage 3. Thus, kidney length alone is sufficient to stratify the risk of progression to renal insufficiency early in ADPKD using either ultrasound or magnetic resonance imaging.
STORAGE PRODUCTS IN SPORES OF ONOCLEA SENSIBILIS L

Lipids and proteins in substantial quantities are present as storage products in spores of Onoclea sensibilis. They fill the sparce spore cytoplasm and ultrastructurally are indistinguishable from reserve materials observed in storage tissue of higher plants. Hydrolysis of both products is correlated with early stages in spore germination. SPORES of Onoclea sensibilis contain chlorophyll, retain considerable amounts of water and, in contrast to non-green spores, are physiologically active. They lack an obvious dormant period. They germinate quickly when placed on a moist surface and gametophyte development appears to progress more rapidly than in spores without chloroplasts. The available evidence (Lloyd and Klekowski, 1970) suggests that both the metabolic and developmental fate of the prothallus may be conditioned by the nature of the reserve food material and its subsequent catabolism. There is very little iAformation available con
Radiation response of reaction-bonded and sintered SiC: Effects of boron isotopes

Abstract The response of mechanical, thermal and microstructural properties of reaction-bonded SiC and sintered SiC were studied after reactor irradiation. The effects of 10 B(n,α) 7 Li reaction products were studied by doping the material from which samples were produced with enriched isotopes of 10 B, 11 B and natural boron. Silicon carbide doped with 10 B exhibits a pronounced effect on the fracture strength. The thermal diffusivity decrease can account for the lowering of the resistance against thermal shock of irradiated material.
Requirements for CD8 T-cell priming, memory generation and maintenance

Immunological memory is characterized by the ability to provide protection from secondary exposure to pathogens. CD8(+) memory T cells provide protection from cell-associated antigens owing to their elevated frequency, rapid response and localization to sites of infection. Events occurring during primary exposure to antigen can impact not only the magnitude and quality of the initial cytotoxic T lymphocyte response but also the efficacy and longevity of the ensuing CD8(+) memory pool. Recent advances shed light on the relative roles of TCR signals and environmental cues in guiding the development of CD8(+) effector T cells into CD8(+) memory T cells and supporting CD8(+) memory T-cell maintenance.
The Complement System in Host Defense and Inflammation

In this discussion I have reviewed the major role of complement in host defense and inflammation. In addition, I have discussed dificiency states. Although these are rare, their clinical signs and symptoms can be predicted, at least in part, on the basis of our current understanding of the biological activities of complement and the various pathways of complement activation. This is not to say that complement plays no role in a wide variety of other illnesses. However, when complement plays a role in an illness, often this is not because it is functioning in an aberrant fashion. The usual situation is that complement is being activated and is serving its normal function in causing inflammation and damage to tissues under abnormal circumstances. Thus, for example, circulating antigen complexes may be deposited in the kidney, activate complement, and mediate tissue inflammation. In this case, complement is functioning normally but is being activated under abnormal circumstances. The same type of analysis can be made for many diseases of many different organ systems. At present, we have no drugs that are effective in humans in controlling the activation of complement and complement-mediated inflammation. We have not yet even established whether local variations in the activity of complement may affect the course of a clinical infection, but there is certainly strongly suggestive evidence to support this idea. It should be clear that under certain circumstances complement may well be a major factor in controlling the course of an infection. The near future should bring a vast expansion in our understanding of how complement contributes to specific clinical illnesses and to the defense of the host against specific microorganisms.
Islands, Exotic Herbivores, and Invasive Plants: Their Roles in Coastal California Restoration

The Pacific islands off southern California, U.S.A. and Baja California, Mexico hold potential for the conservation and restoration of California Mediterranean coastal ecosystems. However, the presence of exotic herbivores and invasive plants pose threats to these systems. Here, we use introduced herbivore removal as a large-scale experimental manipulation to examine the importance of top-down and bottom-up processes to a large-scale restoration effort. Using a paired approach on the Todos Santos Islands, Mexico we removed herbivores from one island, while they temporarily remained on an adjacent and similar island. We augmented this experiment with smaller scale herbivore exclosures on the control island. At both scales we failed to detect an herbivore effect on the plant community; rather plant community dynamics appeared to be dominated by El Nino related precipitation and exotic annuals. A parallel experiment on the San Benito Islands, Mexico revealed a different dynamic: Top-down effects on the plant community by exotic herbivores were evident. Differences in the response from the plant communities to both exotic herbivore presence and removal between these two island groups, along with Santa Barbara Island, U.S.A., where restoration has been on-going, raise important questions in ecosystem restoration. The history of anthropogenic disturbance, exotic plant abundance, and aridity play roles in postherbivore removal recovery. Although island conservation practitioners have honed the ability to remove exotic mammals from islands, development of invasive plant removal techniques is needed to fully capitalize on the conservation potential of California island ecosystems.
Cytokinin and auxin interaction in root stem-cell specification during early embryogenesis

Plant stem-cell pools, the source for all organs, are first established during embryogenesis. It has been known for decades that cytokinin and auxin interact to control organ regeneration in cultured tissue. Auxin has a critical role in root stem-cell specification in zygotic embryogenesis, but the early embryonic function of cytokinin is obscure. Here, we introduce a synthetic reporter to visualize universally cytokinin output in vivo. Notably, the first embryonic signal is detected in the hypophysis, the founder cell of the root stem-cell system. Its apical daughter cell, the precursor of the quiescent centre, maintains phosphorelay activity, whereas the basal daughter cell represses signalling output. Auxin activity levels, however, exhibit the inverse profile. Furthermore, we show that auxin antagonizes cytokinin output in the basal cell lineage by direct transcriptional activation of ARABIDOPSIS RESPONSE REGULATOR genes, ARR7 and ARR15, feedback repressors of cytokinin signalling. Loss of ARR7 and ARR15 function or ectopic cytokinin signalling in the basal cell during early embryogenesis results in a defective root stem-cell system. These results provide a molecular model of transient and antagonistic interaction between auxin and cytokinin critical for specifying the first root stem-cell niche.
Optical control of photodesorption with chirped femtosecond pulses: nonlinear response treatment for CO/Cu(001)

Abstract A recent density matrix treatment of femtosecond photodesorption has been extended to include frequency chirping effects. It describes the dissipative dynamics of desorption and substrate electronic excitations, with an optical Bloch equation and rate equations for the substrate temperature and electron density, including the electron–phonon coupling. Results on CO/Cu(0 0 1) are presented for yield vs. pulse fluence, showing agreement with experimental values, and for chirping effects. Variations of the chirped frequency by ±5% give large changes in the yields. The calculations suggest that chirping can be used to control desorption yields, and to investigate the strength of electron–phonon coupling in metals.
Comparison of selection methods for optimizing genetic gain and gene diversity in a red pine ( Pinus resinosa Ait.) seedling seed orchard

Four selection methods, individual selection (IS), family selection (FS), family plus within-family selection (FWFS) and combined selection (CS), were used to estimate genetic gain [E(g)] for stem volume and gene diversity (GD) for ten theoretical selection intensities in a 108-family, 12-year-old red pine seedling seed orchard. Estimated genetic gain for stem volume ranged from 4.6% to 11.8% across all selection methods and intensities with CS consistently having the highest gains and FS the lowest for any given selection intensity. Genetic diversity ranged from 0.9797 to 0.9954 across all selection methods and intensities. Individual selection was the best selection method for retaining GD, especially at the higher selection intensities, while FWFS was more efficient at the lowest selection intensity. An optimization point, which maximized E(g) and GD relative to each other, was calculated for each selection method. In all cases the optimization point indicated that both E(g) and GD would be favorably high when optimized relative to each other. The implications for volume gain, genetic diversity and potential inbreeding in red pine, a species with inherently low levels of genetic variation, are discussed.
Test Anxiety and Breadth of Encoding Experiences in Free Recall.

Abstract Subjects made three ratings for each of 30 words, then had an unannounced immediate free recall test and a second test after 1 week. There was no evidence to indicate significantly better retention on either test when the dimensions rated were unrelated as opposed to related. Subjects low on test anxiety performed better overall than subjects who scored high on either the emotionality or worry components of test anxiety. On the delayed test, the test anxiety effect was apparent only when study ratings involved unrelated dimensions (i.e., broad encoding). This interaction is consistent with two conclusions. First, rating related dimensions led to narrow encodings, thus hindering low-anxiety subjects who normally encode broadly. Second, even explicit ratings of unrelated dimensions did not induce high-anxiety subjects to encode more broadly. That the high-anxiety deficit was not overcome even with explicit orienting tasks may indicate inflexibility in deploying memory strategies.
Prevalence of water, sanitation and hygiene knowledge, norms and practices in bateyes in La Romana, Dominican Republic

J. Rosenfeld, R. Berggren, K. Dowdell, P. Bropleh, J. Ascher; Center for Medical Humanities & Ethics, University of Texas Health Science Center at San Antonio, San Antonio, TX/US, Center for Medical Humanities & Ethics; University of Texas Health Science Center at San Antonio School of Medicine, San Antonio, TX/US, University of Texas Health Science Center San Antonio, School of Medicine, San Antonio, TX/US
Integral Equations Solution for Reinforced Mode I Cracks Opened by Internal Pressure

The problem of a series of collinear Mode I cracks loaded by a uniform internal pressure is solved by an integral equations technique. By superimposing the solution for an arbitrarily loaded Mode I crack with the solution for an edge loaded infinite strip, a system of integral equations is developed by making the superposition satisfy the required boundary conditions. Solving the integral equations by a least-squares Ritz method gives boundary values which may then be used with the Green’s functions solutions to calculate stress intensity factors for the cracks and the stress and displacement fields in the reinforcement and the cracked regions. By changing the boundary conditions at the reinforcement interface, integral equations modeling other situations such as imperfect bonding may be obtained.
Impairment of Oxidative Phosphorylation by D -threo- and L -threo-Chloramphenicol

WE reported earlier that high concentrations of chloramphenicol impair certain energy-linked functions of mitochondria1,2. The experiments were carried out with the D-threo isomer (the antibiotic) which effectively blocks protein synthesis in bacteria3. Of principal interest is the suppression of respiration and oxidative phosphorylation. If these effects are produced in vivo, it cannot be assumed that responses produced in tissue by D-threo-chloramphenicol are necessarily related to inhibition of protein synthesis. This is not to deny that protein synthesis can be blocked; but it becomes essential that the investigator establishes that impairment of phosphorylation is not also, or even primarily, involved whenever concentrations of the order of 0.5 mg/ml. or greater are used.
Propagation of forces in cells

Cells have the capacity to propagate stress waves. The elasticity and density of protoplasm and the restraint on the protoplasm are significant factors for the determination of the velocities of the waves. When an incoming wave strikes a change in transverse area, reflected and transmitted waves develop, and if the areas have identical structural properties, the relationship of the areas determines the vectorial quantities of the newly formed waves. Stress propagation in neurons develops the velocities and the unidirectional travel patterns that are characteristic of nerve actions.
Mitochondria-associated ER membranes in Alzheimer disease.

Abstract Alzheimer disease (AD) is associated with the accumulation in the brain of extracellular neuritic plaques composed mainly of β-amyloid (Aβ) and of intracellular neurofibrillary tangles composed of hyperphosphorylated forms of the microtubule-associated protein tau. It is also associated with other features that have received less attention, including aberrant phospholipid, cholesterol, and calcium metabolism, and altered mitochondrial function and dynamics. The underlying mechanism(s) that might explain these observations are currently unknown. We recently showed that presenilin-1 (PS1), presenilin-2 (PS2), and γ-secretase activity, which processes the amyloid precursor protein (APP) to generate Aβ, are located predominantly in a specialized subcompartment of the endoplasmic reticulum (ER) that is physically and biochemically connected to mitochondria, called mitochondria-associated ER membranes (MAM). MAM is an intracellular lipid raft-like structure intimately involved in cholesterol and phospholipid lipid metabolism, in calcium homeostasis, and in mitochondrial function and dynamics. The coincidence of the functions associated with MAM with the symptomatology of AD led us to speculate that presenilins play a role in maintaining MAM function. We found that, consistent with this supposition, both MAM function and ER–mitochondrial connectivity are increased significantly in AD, which may help explain many of the biochemical and morphological features of the disease. Based on these findings, we propose that AD is fundamentally a disorder of ER–mitochondrial communication (the “MAM hypothesis”). This article is part of a Special Issue entitled ‘Mitochondrial function and dysfunction in neurodegeneration’.
EPR study of a single crystal of Mn2+ -doped Sr(CH3COO)2 · 12H2O at 295, 77 and 4.2 K

Abstract An X-band EPR study of a single crystal of Mn2+ -doped Sr(CH3COO)2 · 1 2 H2O has been carried out at 4.2, 77 and 295 K. The angular variation of EPR spectra with respect to the orientation of the Zeeman field (B) supports the view that the crystal symmetry of Sr(CH3COO)2 · 1 2H 2 O is triclinic, in disagreement with the monoclinic crystal symmetry predicted by some preliminary X-ray studies. As the temperature is lowered, the overall splitting of the EPR spectrum for B along the magnetic X axis of Mn2+ increases relative to that for B along the magnetic Z axis. Finally, at liquid-helium temperature the overall splitting for B along the room-temperature magnetic X axis becomes larger than that for B along the room-temperature magnetic Z axis, implying the interchange of the magnetic Z and X axes below 77 K. The spin-Hamiltonian parameters for Mn2+ in Sr(CH3COO)2 · 1 2 H2O have been determined at the three temperatures of measurement.