cssi/SciSciGPT-SciSciNet huggingface dataset:
Logic based methods for dynamic risk assessment

Abstract For the origin of logic based methods to assess process plant risks, we go back to the first symposium on Loss Prevention in the United Kingdom in 1971, where concepts in part developed for nuclear power plant risk assessment and extended to process plant have been presented. From there we follow the developments in the 1980s and the benchmarks in Europe in the 1990s revealing the large differences in outcomes when various teams work out the risks of a same plant. It showed the uncertainties intrinsic to the methodology of that time. The last 2 decades have seen various kinds of improvements but also awareness that other factors, such as human failure and organizational ones are important to include. The last subchapter is highlighting approaches partly based on machine learning and artificial intelligence that will make use of “big data,” even enabling dynamic operational risk assessment.
Cannabis Exposure During Critical Windows of Development: Epigenetic and Molecular Pathways Implicated in Neuropsychiatric Disease.

Cannabis exposure during critical windows of development may have intergenerational physiological consequences disrupting epigenetic programming and marks. This review examines the literature relating to pre-gestational and prenatal cannabinoid exposure and its effect on genes and molecular pathways related to the development of psychiatric disease. Developmental cannabis exposure alters epigenetic processes with functional gene consequences. These include potentially heritable alterations in genes and molecular pathways critical for brain development and associated with autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), schizophrenia, addiction, and other psychiatric diseases. Cannabis consumption and mental health illness in adolescents and young adults are increasing in the United States (U.S.), and recent studies suggest that cannabis consumption during critical periods of brain development could contribute to mental health illness through epigenetic mechanisms. These findings warrant future studies and consideration by regulators and health communicators.
A macrocycle directed total synthesis of di-O-methylendiandrin A

The total synthesis of the lignan-based cyclobutane di-O-methylendiandrin A has been achieved using diastereoselective, vicinal alkylation and transannular McMurry reactions of a macrocyclic 1,4-diketone as key transformations for establishing relative stereochemistry and furnishing the strained 4-membered ring of the natural product.
Nightlife scene involvement and patterns of prescription drug misuse.

INTRODUCTION AND AIMS: Participation in nightlife influences a range of health behaviours. Participants in various nightlife scenes have increasingly adopted prescription drug misuse into their substance use repertoires. DESIGN AND METHODS: With 404 young adults recruited via time-space sampling in New York, we examine the relationship of nightlife participation-measured by number of scenes and the number of nights out in nightlife scenes-to prescription drug misuse during the past 3 months. Outcomes included frequency of misuse, escalation to non-oral consumption, polydrug use, social problems and symptoms of dependence. RESULTS: Negative binomial regressions indicate nightlife participation is associated with increased frequency of misuse measured by number of scenes (incidence rate ratio = 1.114, P < 0.05) and number of nights out (incidence rate ratio = 1.009, P < 0.001). Logistic regression models show nightlife participation is associated with increased odds of non-oral use (adjusted odds ratio; AOR = 1.334, P < 0.01) and polydrug use (AOR = 1.776, P < 0.001) measured by number of scenes, and non-oral use (AOR = 1.021, P < 0.001) and polydrug use (AOR = 1.023, P < 0.001) as measured by number of nights out. Nightlife participation is not associated with prescription drug problems or symptoms of dependence. Frequency of participation is associated with peer norms favourable to prescription drugs (B = 0.003, P < 0.01). DISCUSSION AND CONCLUSIONS: Nightlife participation has implications for prescription drug misuse. While shaping how often and in what manner young people consume prescription drugs, nightlife participation is not associated with harms experienced. Given the significance of the prescription drug trend in many world regions, these results suggest that increasing participation in nightlife shapes patterns of drug use, but in ways that do not lead to reported problems.
Effects of cerium oxide nanoparticles and cadmium on corn (Zea mays L.) seedlings physiology and root anatomy

Abstract Heavy metals and engineering nanoparticles (ENPs) are chemical compounds that, in the recent years, have attracted environmental concerns. Particularly, cadmium (Cd) and cerium oxide nanoparticles (CeO2NPs) have attracted researchers' interest because of their chemical and biophysical properties. Most of the previous studies were conducted on C3 plants, which produce three‑carbon compound via the Calvin cycle. This research observed and measured the effects of CeO2NPs and Cd on a C4 species, where photosynthesis makes an intermediate four‑carbon compound that later splits into a three‑carbon compound for the Calvin cycle. Twenty sweet corn seedlings were grown in plastic pots filled with sand under greenhouse conditions and then assigned to a completely randomized experimental design for one month. Four treatments were established: (a.) 0.5 mg kg−1 Cd2+ dry sand, (b.) 500 mg kg−1 CeO2NPs dry sand, (c.) 0.5 mg kg−1 Cd + 500 mg kg−1 CeO2NPs and (d.) 0 mg kg−1 Cd and CeO2NPs as the control. At termination, plant roots and shoots were separated and the concentrations of Cd and Ce in these tissues were determined. Significant differences were found in corn root and leaf biomass, where CeO2NPs promoted the corn growth and development, while Cd hindered the leaf dry weight. No changes were found in chlorophyll contents, but differences were reported in stomatal conductance with higher values registered when CeO2NPs and Cd were applied. Finally, root anatomical changes were analyzed and a clear set of apoplastic barriers closer to the root tip were detected under the exposure of CeO2NPs and Cd. In conclusion CeO2NPs and Cd, alone or in combination, significantly affected the physiology and the root anatomy of corn plants.
Sense of Purpose and Progress Towards Degree in Freshman College Students

This study examined whether first-time full-time freshman students’ sense of purpose predicted their progress towards a degree. Freshman students (N = 421, 62.2% females) completed self-report meas...
Acute and Short-Term Outcomes of Percutaneous Transcatheter Mitral Valve Replacement in Children.

Background Despite the improvement of surgical techniques for mitral valve (MV) repair in children, mitral valve replacement (MVR) is sometimes still necessary. MVR and redo-MVR continue to be burdened by early postoperative mortality and long-term morbidity with only about 75% of these patients being alive or transplant-free 10 years after the initial MVR. Although transcatheter MVR (TMVR) is a well-established intervention in high surgical risk adults, only a few pediatric valve-in-valve case reports have been published. The purpose of this study was to describe our initial experience with the off-label use of the Sapien S3 valve for TMVR in a highly selected pediatric patient population. Methods We conducted a retrospective analysis of pediatric patients who underwent TMVR at Boston Children's Hospital between October 2018 and July 2020. Results Eight consecutive high surgical risk pediatric patients (median age, 9 years; range, 8-15) underwent TMVR (7 as valve-in-valve, 1 in a native MV). Each patient previously underwent multiple MV surgeries or MVR (median 4, range 2-5) and was highly symptomatic (Ross functional class 3 or 4). The indication for TMVR was mitral stenosis in 4 patients, regurgitation in 1, and mixed disease in 3. TMVR was successful in each patient, effectively reduced the left atrium and pulmonary hypertension (P=0.012 and 0.043 respectively), and was carried out without significant complications. Conclusions TMVR is an attractive alternative to MVR in high surgical risk patients. In this small series, TMVR was acutely effective and safe, with very encouraging early results.
Rapid Autopsy Programs and Research Support: The Pre- and Post-COVID-19 Environments

Each rapid autopsy is a powerful opportunity to supply multiple researchers with many valuable tissue specimens at the same time. Since the beginning of the development of rapid autopsy, the overriding organizing principle for all RAPs has been that the samples or organs must be removed and processed as rapidly as possible. To accomplish this some rapid autopsy programs are focused just on one tumor type, while others accept patients demonstrating all tumor types and sometimes other diseases as well. RAPs are logistically complicated and labor-intensive structures, therefore, the key to their success is program flexibility and maintaining a multidisciplinary focus. The necessary collaborations in the complex relationships between clinicians and researchers can be broken down into a series of thought and action steps that must be understood, accepted, and practiced by all participants. A crucial part of the pre-case steps (prior to death) for a rapid autopsy is the study consenting process. It is extremely important that this individualized consent is obtained for postmortem specimens and that it is written in general enough terms to be used for patients with all types of diseases and for an appropriate range of future research uses. The advent of Sars-CoV-2/COVID-19 has presented new challenges and opportunities to the field of autopsy pathology. Guidelines and practice had to be created and adapted to protect physicians and staff while maximizing diagnostic yield. However, any autopsy performed on a patient dying of or with COVID-19 represents a unique opportunity to contribute to understanding of disease mechanisms and to improve death certification, thus assisting in both clinical care and the development of health public policy.
Politics as Method/Method as Politics Part One: Organic Concepts

This chapter interprets the multiple uses of the word “organic” as a way to specify forms of embeddedness. It also interprets how organic concepts offer us a way to methodologize embeddedness as both forms of determination and conditions of possibility (that begin to move beyond the dualism cultural production/societal determinism). In addition, this chapter shows how variations on the meaning of the word organic, and the word itself, appear mostly as adjectives in Gramsci’s work but, also, one variation on the word organic—a term containing the root word organic—appears as a noun. This chapter also shows how when the term organic is used as an adjective it becomes clear that the nouns the adjective “organic” gets attached to define objective and also subjective (or generative) forms of embeddedness. These terms signify the means and processes that constitute the cultural cultivation or production of the political field. Finally, this chapter sets up how the term organic signifies asymmetries, mediations, connections, relations but, in a generative sense, it also signifies correspondences between class, complex social strata, roles embedded within those strata, political organizations, and their upending and reordering (as it pertains to organic crises).
Work Force Diversity Management Strategy: A Catalyst for Global Marketing Competitiveness

This paper builds upon the literature on global marketing strategy and work force diversity management strategy to draw linkages between the two. The overall hypothesis is that work force diversity management strategies can provide a catalyst for developing effective global marketing strategies. The assumption is, a company that assertively cultivates work force diversity management strategies is better equipped to manage the issues associated with global marketing competitiveness. This, in turn, gives the "diversity oriented" company a global competitive edge over other companies.
Religion and Modern Society: Civil religion, citizenship and the business cycle

Introduction: religious asceticism and consumerism In this chapter I return to a familiar issue in classical sociology, namely the relationship between religion and economics. This relationship was famously explored in the Weber thesis on the ‘elective affinity’ between asceticism and rational economic activity (Weber, 2002). In this chapter I want to look at a more specific contemporary issue, namely the relationship between religion and the business cycle in the United States. In an examination of the Great Depression and the New Deal, I explore how America survived the economic crisis of the early 1930s and the public debates that surrounded that defining event in American political and economic history. I conclude the analysis with a brief overview of some of the issues that have emerged from the credit crunch of 2008–9. Franklin D. Roosevelt's economic measures clearly had some success in managing the Depression but the steep downturn in economic activity was solved eventually by America's entry into the Second World War, which created full employment by other means. This period was followed by the creation of a consumer society as yet another response to the business cycle and to the creation of modern citizenship, not by a welfare state, but by what Lizabeth Cohen (2003) called a ‘Consumers' Republic’. With the election of Ronald Reagan in 1980, there was an intensification of strategies to liberate the market from state regulations and there was consequently a ‘financialisation of America’, which has seen, in sociological terms, an increasing dominance of financial elites alongside the long-term decline of American manufacturing industry.
Opportunities for bandwidth adaptation in microsoft office documents

Microsoft Office, the most popular office productivity suite, produces large documents that can result in long download latencies for platforms with limited bandwidth. To reduce latency and improve the user's experience, these documents need to be adapted for transmission on a limited-bandwidth network. To identify opportunities for adaptation, we characterize documents created by three popular applications from the Microsoft Office suite: Word, PowerPoint, and Excel. Our study encompasses over 12,500 documents retrieved from 935 different Web sites. Our main conclusions are: 1) Microsoft Office documents are large and require adaptation on bandwidth-limited clients; 2) embedded objects and images account for the majority of the data in these documents, with image types being the most popular non-text, content, suggesting that adaptation efforts should focus on these elements; 3) compression considerably reduces the sized of these documents; and 4) the internal structure of these documents (pages, slides, or sheets) can be used to download elements on demand and reduce user-perceived latency.
Modeling network bandwidth of IEEE 802.11 wireless local area networks

IEEE 802.11 specifies a standard for physical and MAC layers of wireless local area networks (WLANs). In this paper, network bandwidth of an IEEE 802.11 wireless local area network, defined as an aggregated saturated throughput of the network, is studied in both cases of request-to-send/clear-to-send (RTS/CTS) access method and the basic method. A theoretical model for calculating the network bandwidth from signal-to-noise-ratio (SNR) is proposed and it is evaluated by both simulations and experiments. The result shows that the model is very accurate in measuring or predicting the dynamical network bandwidth of an IEEE 802.11 WLAN when the SNR is higher than 2MB.
The effects of chronic pulmonary disease on hospital length of stay and cost of hospitalization after neurosurgery. Clinical article.

Object Chronic pulmonary diseases (CPDs) are common causes of morbidity. However, their effects on the outcome of the neurosurgical patient population are unknown. In this study, the impact of CPD on length of stay (LOS) and cost of hospitalization (COH) in neurosurgical patients was evaluated. Methods This was a retrospective observational study of all neurosurgical patients at the University of Virginia Health System between 1994 and 2008. Patients were divided into those with CPD (4894) and those without CPD (21,274). Patients were further divided by the types of surgery they underwent: laminectomy, ventriculostomy, and craniotomy. Univariate and multiple linear regression analyses were performed to evaluate the impact of CPD and other comorbidities on LOS and COH. Results Nearly 20% of patients undergoing neurosurgery had CPD. Univariate analysis showed that patients with CPD had a statistically significant increase in LOS and COH after a neurosurgical procedure. The median adjusted COH for patients w...
Diagnosis of sclerosing cholangitis with technetium 99m-labeled iminodiacetic acid planar and single photon emission computed tomographic scintigraphy

Abstract The purpose of this study was to determine whether 99m Tc-iminodiacetic acid planar biliary scintigraphy combined with single photon emission computed tomography could detect sclerosing cholangitis and provide additional information regarding the extent and severity of disease. Thirteen patients with sclerosing cholangitis and 13 normal control subjects were studied. Scintigraphic results were also compared with previously reported studies of patients with isolated common bile duct obstruction and with primary biliary cirrhosis. The planar scintigraphy in patients with sclerosing cholangitis showed beading or bandlike constrictions of the biliary tract corresponding to lesions seen on cholangiography, and the image pattern was distinctly different from images obtained from patients with isolated common bile duct obstruction or primary biliary cirrhosis. The single photon emission computed tomography images of the liver in patients with sclerosing cholangitis demonstrated multiple focal areas of 99m Tc-iminodiacetic acid retention, representing bile stasis in intrahepatic bile ducts. Compared to controls, the mean hepatic clearance half-time of 99m Tc-iminodiacetic acid was markedly delayed in patients with sclerosing cholangitis (6–10 times normal). Individual patients with sclerosing cholangitis had wider variation in isotope clearance half-time from three regions of the liver than patients with isolated common bile duct obstruction, consistent with regionaJ differences in disease severity and variable impairment of bile flow. In 4 patients with sclerosing cholangitis with incomplete filling of the right and left hepatic ducts at cholangiography, planar and single photon emission computed tomographic scintigraphy provided evidence of significant intrahepatic sclerosing cholangitis. In conclusion, combined 99m Tc-iminodiacetic acid planar and single photon emission computed tomographic scintigraphy is a sensitive noninvasive test for the diagnosis of sclerosing cholangitis and reliably differentiates sclerosing cholangitis from isolated common bile duct obstruction or primary biliary cirrhosis. Measurement of isotope clearance half-time provides quantitative physiologic data that may be useful in the longitudinal follow-up of patients with sclerosing cholangitis.
Nonalcoholic fatty liver disease after liver transplantation for cryptogenic cirrhosis or nonalcoholic fatty liver disease

Nonalcoholic steatohepatitis (NASH) may account for many cases of cryptogenic cirrhosis. If so, then steatosis might recur after liver transplantation. Two thousand fifty-two patients underwent primary liver transplantation for chronic liver disease between 1986 and 2004. Serial liver biopsy samples were assessed for steatosis and fibrosis. Two hundred fifty-seven patients (12%) had a pretransplant diagnosis of cryptogenic cirrhosis (239) or NASH (18). Fatty liver developed in 31% and was more common when the pretransplant diagnosis was NASH (45% at 5 years versus 23% for cryptogenic cirrhosis, P = 0.007). NASH developed in only 4% and occurred exclusively when steatosis had already occurred. Steatosis after liver transplantation was associated with the baseline body weight and body mass index by univariate analyses, but no pretransplant or posttransplant characteristic independently predicted steatosis after liver transplantation because obesity was so common in all groups. Five percent and 10% developed bridging fibrosis or cirrhosis after 5 and 10 years, respectively, and this was more common after NASH (31%) than in those who developed steatosis alone (6%) or had no fat (3%, P = 0.002). One-, 5-, and 10-year survival was the same in patients who underwent transplantation for cryptogenic cirrhosis or NASH (86%, 71%, and 56%) and in patients who underwent transplantation for other indications (86%, 71%, and 53%; not significant), but death was more often due to cardiovascular disease and less likely from recurrent liver disease. In conclusion, fatty liver is common after liver transplantation for cryptogenic cirrhosis or NASH but is twice as common in the latter group; this suggests that some cryptogenic cirrhosis, but perhaps not all, is caused by NASH. Posttransplant NASH is unusual, and steatosis appears to be a prerequisite. Advanced fibrosis is uncommon, and survival is the same as that of patients who undergo transplantation for other causes.
Human adipose stem cell and ASC-derived cardiac progenitor cellular therapy improves outcomes in a murine model of myocardial infarction.

BACKGROUND Adipose tissue is an abundant and potent source of adult stem cells for transplant therapy. In this study, we present our findings on the potential application of adipose-derived stem cells (ASCs) as well as induced cardiac-like progenitors (iCPs) derived from ASCs for the treatment of myocardial infarction. METHODS AND RESULTS Human bone marrow (BM)-derived stem cells, ASCs, and iCPs generated from ASCs using three defined cardiac lineage transcription factors were assessed in an immune-compromised mouse myocardial infarction model. Analysis of iCP prior to transplant confirmed changes in gene and protein expression consistent with a cardiac phenotype. Endpoint analysis was performed 1 month posttransplant. Significantly increased endpoint fractional shortening, as well as reduction in the infarct area at risk, was observed in recipients of iCPs as compared to the other recipient cohorts. Both recipients of iCPs and ASCs presented higher myocardial capillary densities than either recipients of BM-derived stem cells or the control cohort. Furthermore, mice receiving iCPs had a significantly higher cardiac retention of transplanted cells than all other groups. CONCLUSION Overall, iCPs generated from ASCs outperform BM-derived stem cells and ASCs in facilitating recovery from induced myocardial infarction in mice.
Lower Limb Nerve Entrapment Syndromes

The largest nerve in the body, the sciatic nerve, divides into the peroneal and tibial nerves proximal to the popliteal fossa. Patients with peroneal nerve injury present with foot drop, frequent falls, and dysesthesias over lateral half of anterior leg and/or dorsum of the foot. Gender-related concerns in peroneal neuropathy include prolonged knee flexion during parturition, female prevalence of gastric bypass, and female prevalence of ligamentous knee injuries. Patients with tibial nerve injury present with dysesthesias over medial malleolus and/or sole of the foot including the toenails, nocturnal exacerbation of symptoms, and motor weakness in plantar flexion and/or inversion of ankle. Gender issues in tibial neuropathy include prevalence of rheumatologic disease and ligamentous injuries in women.
Mn4Ca Cluster in Photosynthesis: Where and How Water is Oxidized to Dioxygen

Oxygen, which supports all aerobic life, is produced by photosynthetic water oxidation in plants, algae, and cyanobacteria. The water-oxidation reaction probably first appeared in nature ∼3 billion years ago in the precursors to present-day cyanobacteria, although the exact timing is not yet entirely clear.1−5 A key component in the appearance of oxygenic photosynthesis was a metal complex that could store oxidizing equivalents to facilitate the four-electron oxidation of two water molecules to dioxygen, meanwhile making the electrons available for the reductive carbon-fixing reactions required for sustaining life.6−8 This metal complex involved in oxygenic photosynthesis, the oxygen-evolving complex (OEC), consists of an oxo-bridged structure with four Mn atoms and one Ca atom. No variations have been observed so far among oxygenic photosynthetic organisms through higher plants and algae back to cyanobacteria, which represents the earliest oxygenic photosynthetic organisms. Oxygen itself is the byproduct of the photosynthetic water oxidation reaction shown in eq 1: 1 However, it was this oxygen that enabled oxygenic life to evolve and that led to the current diverse and complex life on earth by dramatically increasing the metabolic energy that became available from aerobic respiration. Oxygen produced by this process was also key for the development of the protective ozone layer, which allowed life to transition from marine forms to terrestrial life.
Sow culling and mortality in commercial swine breeding herds

Abstract Six months of production data from 18 commercial swine breeding PBherds were used to describe reason-specific removal rates and the amount of time lost between farrowing and removal for each removal reason. There were 774 females removed during the 6-month analysis period. The removal rate for the study period was 25.0%, equivalent to an annual rate of 50%. Four major reason groups accounted for 70% of all removals: reproductive failure, degenerative problems, locomotor problems and death. Reproductive failure was the most likely removal reason across all parity groups except parity ⩾7, in which degenerative problems were much more likely and reproductive failure ranked second. The average time required from farrowing to removal across all reason groups was 78 days. Reproductive failure clustered at >10 weeks, with an average time to removal of 128 days. Removals for degenerative problems clustered at Weeks 4–6 and at >10 weeks, with an average time to removal of 57 days. Death clustered at Week 1 and at >10 weeks, with an average time to removal of 72 days. Locomotor problems clustered at Weeks 5–8, with a second peak at > 10 weeks; the average time to removal was 58 days. Most females were removed involuntarily, and as the replacement rate increased a higher proportion of all removals were involuntary.
Long-Term Retention of Information about Presentation Modality by Children and Adults.

A mixed-modality continuous recognition task followed by a final recognition test after 0 h, 4 h, 1 day, or 7 days was administered to third- and fourth-grade children and adults. Subjects gave recognition responses and reported presentation modalities. Forgetting rates for both words and input mode were invariant with age. The decay functions for presentation modality were affected, however, by the initial input mode, with modality identification declining more rapidly for words heard first than for words seen first. Information about whether a word was seen or heard remained in memory for at least 4 h. The results demonstrate that long-term-memory representations contain a great deal of information about input mode and suggest that the theoretical distinction between automatic and effortful processing may be a useful one.
Laminin-binding integrin alpha 7 beta 1: functional characterization and expression in normal and malignant melanocytes.

Abstract A novel integrin, alpha 7 beta 1, that specifically binds with high affinity to laminin has been identified on melanoma cells. This complex was purified from both human and murine melanoma cells by laminin-affinity chromatography, and the alpha 7 subunit was recovered after gel electrophoresis. N-terminal amino acid sequence analysis of the alpha 7 subunit from both human and mouse cells verifies that this integrin is distinct from other alpha chains in the beta 1 family, although strikingly similar to the alpha 6 subunit. By using specific proteolytically derived fragments of laminin, it was determined that the alpha 7 beta 1 complex binds selectively to the E8 region, which represents part of the long arm of laminin. In contrast, the receptor failed to bind to the P1 fragment, which contains the intersection of the short arms of laminin. Although the alpha 7 beta 1 complex was commonly expressed in melanoma cells, this integrin was not detected in normal melanocytes, suggesting that alpha 7 expression may be associated with malignant transformation. These results establish the existence of a novel integrin that binds to the E8 domain of laminin and appears to mediate cell adhesion to this ligand.
Quantitative in situ infrared analysis of reactions between trimethylaluminum and polymers during Al2O3 atomic layer deposition

The reactions of trimethylaluminum (TMA) toward substrates during the Al2O3 atomic layer deposition (ALD) on a variety of polymers were studied by in situ Fourier transform infrared spectroscopy (FTIR). The experiments demonstrate that TMA reacts with certain nucleophilic functional groups on the polymer surface during the first several ALD cycles. For some polymer substrates, TMA vapor penetrates into the polymer and reacts in the polymer bulk. In both cases, the initial reaction plays an important role in the nucleation and growth of Al2O3. For chemically inert polymers, such as polypropylene, nucleation of Al2O3 ALD is relative slow at the initial stage due to the lack of reactive groups on the substrate. However, polyester, polyamide and polyether are more reactive, and in situ FTIR spectra showed a larger extent of reaction with TMA, facilitating the nucleation of ALD film on these polymers. By comparing FTIR spectra, we quantitatively estimate the extent of TMA reaction towards different polymers, and confirmed the results using X-ray photoelectron spectroscopy and scanning electron microscopy. Results give insight into the importance of the polymer structure in determining the nature and extent of the reaction during ALD film processing on polymer substrates.
Interaction of high-power infrared radiation with germanium

We have observed and characterized wavelength-dependent laser damage thresholds in crystalline germanium induced by trains of high-power infrared picosecond laser pulses at wavelengths ranging from 2.8 μm to 5.2 μm, using the Vanderbilt Free-Electron Laser. In this wavelength range, photon energies are well below the band-gap energy. As the wavelength is increased, threshold fluences are observed to increase by a factor of five over the studied wavelength range. Two- and three- photon absorption is the predominant photon energy absorption mechanism up to 4.4 μm. At wavelengths above 4.8 μm tunnel absorption appears to be the primary absorption mechanism. Wavelength and fluence dependent transmission and reflection measurements provide valuable insight into the nature of the damage mechanisms.
Targeting and modification of prokaryotic cell–cell junctions by tobacco mosaic virus cell-to-cell movement protein

Summary The movement protein (MP) of tobacco mosaic virus (TMV) facilitates the cell-to-cell spread of infection by altering the structure and function of plasmodesmata, the intercellular communication channels in plants. Because the protein was shown to interfere with intercellular communication when expressed in the cyanobacterium Anabaena sp. strain PCC 7120, whether the ability of the protein to target and to modify intercellular communication channels in plants is conserved in this prokaryote was investigated. It was found that the MP localizes to the cell junctions and induces the formation of filamentous structures that traverse the septa. It is proposed that the protein interacts with host components that are similar between plants and Anabaena and that may be evolutionarily related. The observations in Anabaena suggest that the MP modifies plasmodesmata by forming a filamentous aggregate within the pore.
Rekindling the search for the Holy Braille

Summary form only given. In 1987 Alan Kay pointed out that the development of interfaces to computers is going backwards. Whereas children begin building their understanding of the world through embodied exploration, then “advance” to learning through images and finally reach the “sophisticated” state of symbolic understanding, our interaction with computers began by being symbolic, progressed through the GUI and only now is reaching the point where we can explore computational environments through movement and touch. While this has certainly been true for mainstream computing, interaction for people with visual impairments got stuck at the symbolic phase. We still use command lines and keyboard shortcuts to navigate through our interfaces, and they still communicate with us through words (either spoken or, very occasionally, through the symbolic code of Braille. In many ways, therefore, blind computer users have not been able to take advantage of the revolution in information presentation facilitated by computation that has changed the lives of their sighted peers. And this is not for lack of trying to find alternative ways for blind individuals to access non-textual information. There is a long history of attempts to build refreshable tactile displays and, more recently, of using haptic feedback to present graphs, maps and 3D models to blind computer users. But in most cases the main stumbling block has been the cost and availability of suitable hardware for this purpose. The search is on, therefore, for a low-cost full-page refreshable tactile display that can convey both text and graphics. Such a display would allow for the presentation of spatial information such as curves and lines in graphs, shapes of objects in pictures and maps, and the display of spatially-dependent Braille codes for mathematics and music. A second part of the process of designing effective tactile and/or haptic information displays is in understanding how to convey spatial and relational information through touch. Here too, there is a substantial body of work on haptic spatial perception, haptic exploration, and on the perception of tactile diagrams and images upon which we as designers can draw. In this talk, I will introduce our own bid to find the Holy Braille. I will first review relevant work in both hardware design and haptic perception. I will then discuss our design process for an interactive product that takes full account of the many perceptual and cognitive layers inherent in presenting information in tangible form to users who have little or no vision. In particular I will discuss the knotty issue of understanding the differences between xviii sensory substitution, symbolic translation, and semantic interpretation, and the potential pitfalls of misunderstanding the relationship between these three categories of information presentation.
Anonymous credentials with biometrically-enforced non-transferability

We present a model and protocol for anonymous credentials. Rather than using deterrents to ensure non-transferability, our model uses secure hardware with biometric authentication capabilities.Using the model combining biometric authentication with anonymous credentials in the wallet-with-observer architecture proposed by Bleumer [4], we formalize the requirements of an anonymous credential protocol. In doing so, we define what it means for a protocol to be strongly subliminal-free, and show that any protocol meeting this new definition can be used in a non-transferable anonymous credential system. Our new definition improves upon subliminal-freeness as used by Burmester et al [10], in that we restrict information flow among parties even when one party detects that others in the protocol are dishonest.We describe a new protocol which is strongly subliminal-free. We then extend this basic model in a modular way to include the additional feature that the issuing authority may revoke credentials via a single (broadcast) message. Finally, we present a second protocol in the extended model.
Sleeping under the risk of predation

Every studied animal engages in sleep, and many animals spend much of their lives in this vulnerable behavioural state. We believe that an explicit description of this vulnerability will provide many insights into both the function and architecture (or organization) of sleep. Early studies of sleep recognized this idea, but it has been largely overlooked during the last 20 years. We critically evaluate early models that suggested that the function of sleep is antipredator in nature, and outline a new model in which we argue that whole-brain or ‘blackout’ sleep may be the safest way to sleep given a functionally interconnected brain. Early comparative work also suggested that the predatory environment is an important determinant of sleep architecture. For example, species that sleep in risky environments spend less time in the relatively vulnerable states of sleep. Recent experimental work suggests that mammals and birds shift to relatively vigilant (lighter) states of sleep in response to an increase in perceived risk; these results mirror the influence of stress on sleep in humans and rats. We also outline a conceptual model of sleep architecture in which dynamic changes in sleep states reflect a trade-off between the benefits of reducing a sleep debt and the cost of predation. Overall, many aspects of plasticity in sleep related to predation risk require further study, as do the ways in which sleeping animals monitor predatory threats. More work outside of the dominant mammalian paradigm in sleep is also needed. An ecologically based view of sleeping under the risk of predation will provide an important complement to the traditional physiological and neurological approaches to studying sleep and its functions.
Anticonflict and discriminative stimulus effects of the 5-HT1A compounds WY-47,846 and WY-48,723 and the mixed 5-HT1A agonist/5-HT2 antagonist WY-50,324 in pigeons

The effects of the pyrimidinylpiperazinyl imide WY-47,846 (zalospirone), the substituted arylpiperazine WY-48,723, and the adamantyl piperazine derivative WY-50,324 were studied under punishment (conflict) procedures with pigeons to evaluate potential anxiolytic activity. These compounds were also studied in pigeons trained to discriminate administration of the serotonin (5-HT)1A agonist 8-hydroxy-2-(di-n-propylamino) tetralin [8-OH-DPAT] (0.3 mg/kg) or buspirone (1.0 mg/kg), both administered i.m., from saline. All three compounds have high affinity for the 5-HT1A receptor site and WY-50,324 also has high affinity for 5-HT2 receptors, with activity as an antagonist at this site. Increases in punished responding occurred with all three drugs, with the magnitude of the increases in the order WY-50,324 > WY-48,723; > WY-48,846; increases with WY-50,324 reached almost 15,000% of control levels. Increases in punished responding occurred at doses that did not affect unpunished responding. Doses producing maximal effects of the three drugs were comparable (1.0 mg/kg), although WY-48,723 and WY-50,324 also produced large increases at doses as low as 0.1 mg/kg. All three drugs also substituted for 8-OH-DPAT and buspirone, with WY-48,723 and WY-50,324 producing complete substitution at 0.1–0.3 mg/kg, whereas WY-47,846 did not substitute in 8-OD-DPAT-trained pigeons until a dose of 10 mg/kg; in pigeons trained with buspirone, a dose of 1.0 mg/kg WY-47,846 resulted in complete substitution. All three drugs appear to have potential anxiolytic and/or antidepressant activity through actions mediated at the 5-HT1A receptor. The unique combination of 5-HT1A agonist activity with 5-HT2 antagonist activity appears to confer potent anxiolytic-like actions on WY-50,324 that prompt additional exploration of the interactions between these receptor subtypes and their role in anxiety and other disorders.
Functional conservation of Schistosoma mansoni Smads in TGF-β signaling.

To begin to understand the molecular basis of communication between the parasite Schistosoma mansoni and its mammalian host, we are studying the signaling pathway downstream of S. mansoni receptor kinase-1 (SmRK1), a divergent type I transforming growth factor-beta (TGF-beta) receptor found on the tegumental surface of the parasite. In this study, we have used a homology based PCR approach to clone two S. mansoni Smad (SmSmad) genes; Smads play a pivotal role in the most well understood signaling pathways initiated by the TGF-beta family of ligands in other organisms. Comparison of the amino acid sequences with those of other Smads reveals that the conserved MH1 and MH2 domains of SmSmads show a high degree of identity to homologues in Drosophila. Transcripts for both SmSmads are detected in the same developmental stages as SmRK1, and both are capable of interacting with the intracellular domain of the receptor in vitro. Functional characterization using the human type I TGF-beta receptor further confirms the highly conserved nature of these proteins, as both SmSmads show TGF-beta dependent enhancement of luciferase activity and nuclear translocation in mammalian cells. These data are the first to show a TGF-beta-like receptor/Smad signaling pathway in parasitic helminths and by analogy with other systems, is likely important in regulating schistosome development.
Compounds formed on the reduction of ReO4− in the presence of oximes and 2-pyridines

Abstract Reduction of ReO 4 − by Sn(II) in the presence of dioxime ligands leads to Re(V) compounds. Two products were isolated with diphenylglyoxime; ReL 2 Cl 2 and ReL 2 Cl 3 , where the charge balance is maintained by loss of protons from the dioximes (L). Substituted pyridine ligands under similar conditions form pyridinium salts of Re(III) or Re(IV); but bis-(2-pyridyl) glycol stabilizes Re(V) by chelation, forming ReLOCl 2 and ReLOCl 3 , where again protons are lost from the organic ligand.
Improving Communication Near the End of Life

Research suggests that communication near the end of life is problematic. A literature review was conducted to identify barriers to optimal communication near the end of life and strategies to over...
L’asthme sévère est souvent allergique chez l’enfant

Resume Actuellement, c’est le non-controle de l’asthme malgre une pression therapeutique elevee qui definit l’asthme severe. Il existe cependant differents phenotypes d’asthmes severes. Ces phenotypes sont distingues suivant que l’absence de controle est definie par : des exacerbations aigues graves ; un syndrome obstructif persistant precoce, parfois lie au declin trop rapide de la fonction respiratoire au cours de l’enfance ; l’association des deux types precedents, notamment en cas de corticoresistance partielle ou totale. Chez l’enfant, l’atopie est souvent responsable de ces phenotypes d’asthme severe et egalement de la persistance de l’asthme au cours de l’enfance, puis a l’âge adulte.
Polyol synthesis of Cu2O nanoparticles: use of chloride to promote the formation of a cubic morphology

We have employed the polyol method to synthesize copper(I) oxide (Cu2O) nanostructures with well-defined shapes and in large quantities. Transmission electron microscopy and X-ray powder diffraction studies show that polycrystalline colloidal spheres could be prepared in high yields by simply reducing copper nitrate with ethylene glycol heated to 140 °C in the presence of poly(vinyl pyrrolidone). When a small amount of sodium chloride was introduced, single-crystal nanocubes were obtained. In this case, chloride seems to play a pivotal role in controlling the formation of seeds and the growth rates of various crystallographic planes to shape the Cu2O nanostructures into nanocubes. Based on the structural analysis of samples obtained at different growth times, we also proposed a plausible mechanism to account for the formation of these two distinctive morphologies under different conditions.
The SiGeSn approach towards Si-based lasers

Abstract Approaches using lattice-matched heterostructures consisting of group-IV elements – Si, Ge, Sn and their alloys, are proposed for the development of Si-based lasers that can be monolithically integrated on Si substrate. All proposed laser structures can be deposited strain free on Si substrates with either Ge or GeSn buffer layers. Designs of double heterostructure, multiple quantum well, and quantum cascade lasers are presented.
Dependence of craze velocity on stress and on the absorption and diffusion of environmental gases

Abstract A comprehensive equation for the velocity of a craze in an environmental gas was obtained in terms of the stress, temperature, and partial pressure of the gas. The physical parameters of the gas that enter the equation are boiling point, heat of vaporization and diffusion coefficient. The equation is based on the viewpoint that a steady-state velocity is determined by a thermally activated deformation process wherein the plasticization of the polymer by the gas reduces the activation energy. At low velocities the process is not diffusion-limited, and therefore the logarithm of the velocity is a linear function of pressure and stress. At higher velocities the logarithm of velocity increases less rapidly with stress and pressure because the penetration of gas into the polymer is decreased by the velocity as it constantly generates a fresh gas-polymer interface. The agreement between the equation and the experimental data is demonstrated.
Kinetics of formation of fibrin oligomers. III. Ligation kinetics concurrent with and subsequent to oligomer assembly.

Human fibrinogen was treated with thrombin in the presence of fibrinoligase (Factor XIIIa) and calcium ion at pH 8.5, ionic strength 0.45, and the ensuing polymerization was interrupted at various time intervals (t) both before and after the clotting time (tc) by solubilization with a solution of sodium dodecyl sulfate and urea. Aliquots of the solubilized protein were subjected to gel electrophoresis on polyacrylamide gels after disulfide reduction by dithiothreitol and on agarose gels without reduction. The degree of γ-γ ligation was determined from the former. The latter provided the size distribution of ligated end-to-end sequences produced by splitting the ligated staggered overlapped oligomers down the middle, for degrees of polymerization, x, from 1 to 10. Addition of fibrinoligase (in which the activating thrombin had been inhibited by p-nitrophenyl-p′-guanidinobenzoate, NPGB) to Kabi fibrinogen showed the presence of small amounts of ligatable oligomers. Addition of fibrinoligase to a polymerizing mixture in which the action of thrombin had been stopped before clotting by NPGB produced the same distribution of ligated end-to-end sequences that was obtained when fibrinoligase was originally present, at least for reaction times up to 0.7 of the clotting time. The kinetics of γ-γ ligation by fibrinoligase acting on a polymerized mixture stabilized by NPGB were followed. The reaction was first order in the concentration of ligatable γ-γ junctions and the initial velocity was proportional to the enzyme concentration. The time evolution of size distribution of ligated end-to-end sequences agreed with a theory based on random ligation of ligatable junctions.
Microtektite Surface Sculpturing

Microtektites recovered from deep-sea sediments have unique surface sculpturing. Many of the surface features (pits, U-shaped grooves, mounds) are similar to those observed on tektites from adjacent strewn fields. Some surface features are characteristic of microtektites from a given strewn field (for example, star-shaped pits on North American microtektites and U-shaped and V-shaped grooves on Ivory Coast microtektites). The surface sculpturing was apparently produced by solution prior to burial on the ocean floor. Some of the surface features (such as star-shaped pits, U-shaped grooves, and silica-rich protrusions) were apparently due to heterogeneities at the surface of the microtektites or in a stress shell and cannot be reproduced by etching interior surfaces.