A Perspective on Substorm Dynamics Using 10 Years of Auroral Kilometric Radiation Observations From Wind.

We study 10 years (1995-2004 inclusive) of auroral kilometric radiation (AKR) radio emission data from the Wind spacecraft to examine the link between AKR and terrestrial substorms. We use substorm lists based on parameters including ground magnetometer signatures and geosynchronous particle injections as a basis for superposed epoch analyses of the AKR data. The results for each list show a similar, clear response of the AKR power around substorm onset. For nearly all event lists, the average response shows that the AKR power begins to increase around 20 min prior to expansion phase onset, as defined by the respective lists. The analysis of the spectral parameters of AKR bursts show that this increase in power is due to an extension of the source region to higher altitudes, which also precedes expansion phase onset by 20 min. Our observations show that the minimum frequency channel that observes AKR at this time, on average, is 60 kHz. AKR visibility is highly sensitive to observing spacecraft location, and the biggest radio response to substorm onset is seen in the 21:00-03:00 hr local time sector.

Viscoelastic haemostatic point-of-care assays in the management of postpartum haemorrhage: a narrative review.

Viscoelastic haemostatic assays provide rapid testing at the bed-side that identify all phases of haemostasis, from initial fibrin formation to clot lysis. In obstetric patients, altered haemostasis is common as pregnancy is associated with coagulation changes that may contribute to bleeding events such as postpartum haemorrhage, as well as thrombosis events. In this narrative review, we examine the potential clinical utility of viscoelastic haemostatic assays in postpartum haemorrhage and consider the current recommendations for their use in obstetric patients. We discuss the clinical benefits associated with the use of viscoelastic haemostatic assays due to the provision of (near) real-time readouts with a short turnaround, coupled with the identification of coagulation defects such as hypofibrinogenaemia. The use of viscoelastic haemostatic assay-guided algorithms may be beneficial to diagnose coagulopathy, predict postpartum haemorrhage, reduce transfusion requirements and monitor fibrinolysis in women with obstetric haemorrhage. Further studies are required to assess whether viscoelastic haemostatic assay-guided treatment improves clinical outcomes, and to confirm the utility of prepartum viscoelastic haemostatic assay measurements for identifying patients at risk of postpartum haemorrhage.

When and how should I transfuse during obstetric hemorrhage?

The incidence of maternal hemorrhage and blood transfusion has increased over time. Causes of massive hemorrhage, defined as a transfusion > 10 units of erythrocytes, include abnormal placental insertion, preeclampsia, and placental abruption. Although ratio-based transfusion has been described for managing massive hemorrhage, a goal-directed approach using laboratory or point-of-care data may lead to better outcomes. Autotransfusion, which involves the collection, washing, and filtration of maternal shed blood, avoids many of the complications associated with allogeneic blood transfusion. In this review, we provide an overview of transfusion practices related to the management of obstetric hemorrhage.

Dispersal Reduction: Causes, Genomic Mechanisms, and Evolutionary Consequences.

Recent biological analyses suggest that reductions in dispersal ability have been key drivers of diversification across numerous lineages. We synthesise emerging data to highlight similarities regarding the causes and consequences of dispersal reduction across taxa and ecosystems, as well as the diverse genomic mechanisms underpinning these shifts. Natural selection has acted on standing genetic variation within taxa to drive often rapid - and in some cases parallel - losses of dispersal, and ultimately speciation. Such shifts can thus represent an important nexus between adaptive and neutral diversification processes, with substantial evolutionary consequences. Recognition of the links between these concepts that are emerging from different fields, taxa and ecosystems is transforming our understanding of the fascinating role of dispersal reduction in the formation of biodiversity.

Separation of hemodynamic signals from GCaMP fluorescence measured with wide-field imaging.

Wide-field calcium imaging is often used to measure brain dynamics in behaving mice. With a large field of view and a high sampling rate, wide-field imaging can monitor activity from several distant cortical areas simultaneously, revealing cortical interactions. Interpretation of wide-field images is complicated, however, by the absorption of light by hemoglobin, which can substantially affect the measured fluorescence. One approach to separating hemodynamics and calcium signals is to use multiwavelength backscatter recordings to measure light absorption by hemoglobin. Following this approach, we develop a spatially detailed regression-based method to estimate hemodynamics. This Spatial Model is based on a linear form of the Beer-Lambert relationship but is fit at every pixel in the image and does not rely on the estimation of physical parameters. In awake mice of three transgenic lines, the Spatial Model offers improved separation of hemodynamics and changes in GCaMP fluorescence. The improvement is pronounced near blood vessels and, in contrast with the Beer-Lambert equations, can remove vascular artifacts along the sagittal midline and in general permits more accurate fluorescence-based determination of neuronal activity across the cortex.NEW & NOTEWORTHY This paper addresses a well-known and strong source of contamination in wide-field calcium-imaging data: hemodynamics. To guide researchers toward the best method to separate calcium signals from hemodynamics, we compare the performance of several methods in three commonly used mouse lines and present a novel regression model that outperforms the other techniques we consider.

A New Realization of SI for Organic Chemical Measurement: NIST PS1 Primary Standard for Quantitative NMR (Benzoic Acid).

Metrological traceability to common references supports the comparability of chemical measurement results produced by different analysts, at various times, and at separate places. Ideally, these references are realizations of base units of the International System of Units (SI). ISO/IEC 17025 (Clause 6.5) states that traceability of measurement results is a necessary attribute of analytical laboratory competence, and as such, has become compulsory in many industries, especially clinical diagnostics and healthcare. Historically, claims of traceability for organic chemical measurements have relied on calibration chains anchored on unique reference materials with linkage to the SI that is tenuous at best. A first-of-its-kind National Institute of Standards and Technology (NIST) reference material, ultrapure and extensively characterized PS1 Benzoic Acid Primary Standard for quantitative NMR (qNMR), serves as a definitive, primary reference (calibrant) that assuredly links the qNMR spectroscopy technique to SI units. As qNMR itself is a favorable method for accurate, direct characterization of chemical reference materials, PS1 is a standard for developing other traceable standards and is intended to establish traceability for the measurement of thousands of organic chemical species. NIST PS1 will play a critical role in directly promoting accuracy and worldwide comparability of measurement results produced by the chemical measurement community, supporting the soundness of clinical diagnostics, food safety and labeling, forensic investigation, drug development, biomedical research, and chemical manufacturing. Confidence in this link to the SI was established through (i) unambiguous identification of chemical structure; (ii) determinations of isotopic composition and molecular weight; (iii) evaluation of the respective molecular amount by multiple primary measurement procedures, including qNMR and coulometry; and (iv) rigorous evaluation of measurement uncertainty using state-of-the-art statistical methods and measurement models.

Space-brain: The negative effects of space exposure on the central nervous system.

Journey to Mars will be a large milestone for all humankind. Throughout history, we have learned lessons about the health dangers associated with exploratory voyages to expand our frontiers. Travelling through deep space, the final frontier, is planned for the 2030s by NASA. The lessons learned from the adverse health effects of space exposure have been encountered from previous, less-lengthy missions. Prolonged multiyear deep space travel to Mars could be encumbered by significant adverse health effects, which could critically affect the safety of the mission and its voyagers. In this review, we discuss the health effects of the central nervous system by space exposure. The negative effects from space radiation and microgravity have been detailed. Future aims and recommendations for the safety of the voyagers have been discussed. With proper planning and anticipation, the mission to Mars can be done safely and securely.

Operative and Therapeutic Advancements in Breast Cancer Metastases to the Brain.

Patients with breast cancer are surviving longer as the state of the art for care advances. Because patients are surviving longer with primary breast cancer, the incidence of secondary metastatic disease has risen. Metastatic breast cancer to the brain was once thought to be universally fatal. While it is still quite lethal, its treatment after diagnosis is increasingly safe and effective. Critical progress has been made in understanding the interaction between breast metastases and the neural niche, neuroimaging of functional anatomy, minimally invasive image-guided brain surgery, characterizing subtypes of breast cancer based on molecular and genetic profiles, and individualized pharmaceuticals and immunotherapies. In this review, we discuss recent advances that have brought us to state-of-the-art management of metastatic breast cancer to the brain.

Enhancing the dissolution of phenylbutazone using Syloid? based mesoporous silicas for oral equine applications / 药物分析学报

Three mesoporous silica excipients (Syloid? silicas AL-1 FP, XDP 3050 and XDP 3150) were formulated with a model drug known for its poor aqueous solubility, namely phenylbutazone, in an attempt to enhance the extent and rate of drug dissolution. Although other forms of mesoporous silica have been investigated in previous studies, the effect of inclusion with these specific Syloid? silica based excipients and more interestingly, with phenylbutazone, is unknown. This work reports a significant enhancement for both the extent and rate of drug release for all three forms of Syloid? silica at a 1:1 drug:silica ratio over a period of 30 min. An explanation for this increase was determined to be conversion to the amorphous form and an enhanced drug loading ability within the pores. Differences between the release profiles of the three silicas were concluded to be a consequence of the physicochemical differences between the three forms. Overall, this study confirms that Syloid? silica based excipients can be used to enhance dissolution, and potentially therefore bioavailability, for compounds with poor aqueous solubility such as phenylbutazone. In addition, it has been confirmed that drug release can be carefully tailored based on the choice of Syloid? silica and desired release profile.

An Interstitial 4q Deletion with a Mosaic Complementary Ring Chromosome in a Child with Dysmorphism, Linear Skin Pigmentation, and Hepatomegaly.

Interstitial deletions of 4q are rarely reported, vary in size, and have limited genotype-phenotype correlations. Here, genome-wide array CGH analysis identified a 21.6 Mb region of copy number loss at 4q12-q21.1 in a patient diagnosed with dysmorphism, linear skin pigmentation, and hepatomegaly. An additional small ring chromosome was detected in 5/30 cells examined via G-banding. Confirmation of the origin of the ring chromosome was obtained by FISH analysis which identified that the ring chromosome contained material from the deleted region of chromosome 4 and was therefore complementary to the 21.6 Mb deletion. Further microarray studies in the proband using a different microarray platform showed no evidence of mosaicism. This case highlights the importance of an integrated approach to cytogenetic analysis and demonstrates the value of G-banding for detecting mosaicism, as current microarray platforms are unable to detect low level mosaics.

Adult extracorporeal membrane oxygenation: an international survey of transfusion and anticoagulation techniques.

BACKGROUND AND OBJECTIVES: Extracorporeal membrane oxygenation (ECMO) is a method of life support for either isolated cardiac failure or respiratory failure, with or without cardiac failure. When used for hemodynamic support, the ECMO circuit presents a non-endothelialized, artificial surface to blood inciting an inflammatory response which activates haemostatic pathways. Anticoagulation may complicate a pre-existing coagulopathy and/or inadequate surgical hemostasis of varying severity. There is no standardized method to achieve and monitor anticoagulation or guide transfusion therapy during ECMO. We tested the hypothesis that institutions across the world conduct similar management of anticoagulation and transfusion during adult ECMO support. METHODS: This is a descriptive, self-reporting cross-sectional survey of anticoagulation and transfusion practice for patients age 18 or older on ECMO. This 38 multiple-choice question survey was sent to 166 institutions, internationally, utilizing adult ECMO. About 32·4% (54) of institutions responded. Responses were anonymously collected. Descriptive analyses were calculated. RESULTS: Our findings indicate there appears to be a significant practice variation among institutions regarding anticoagulation and transfusion during adult ECMO support. DISCUSSION: The lack of standard practices among institutions may reflect a paucity of data regarding optimal anticoagulation and transfusion for patients requiring ECMO. Standardized protocols for anticoagulation and transfusion may help increase quality of care for and reduce morbidity, mortality and cost to patients and healthcare centres. Further study is required for standardized, high quality care.

The effects of a data driven maximum surgical blood ordering schedule on preoperative blood ordering practices.

OBJECTIVES: The maximum surgical blood ordering schedule (MSBOS) provides guidelines for pre-operative pre-transfusion testing for elective surgical procedures. This study compared blood ordering and utilization during the period when the MSBOS was created by achieving consensus between the blood bank and the various surgical specialties, and after the introduction of an MSBOS created by using department-specific red blood cell (RBC) transfusion data (data driven MSBOS, dMSBOS). METHODS: The dMSBOS was created by analyzing 12 months of RBC transfusion data for each procedure across a regional health system. Pre-transfusion testing and the RBC crossmatch:transfusion (C:T) ratios at 8 of the hospitals were compared between the 12 month period before the dMSBOS was introduced, and the 15 months after its introduction. RESULTS: There were significant reductions in the median monthly number of type and screens not associated with RBC crossmatches (10 714-10 061; p < 0.0001) and the median number of type and screens associated with RBC crossmatches (10 127-9 349; p = 0.0014) on surgical patients after dMSBOS implementation. There were significant decreases in the median number of monthly RBC units crossmatched (2 981-2 444; p < 0.0001) and transfused (890-791; p < 0.0001) to surgical patients after implementing the dMSBOS. The overall system-wide C:T ratio trended down after dMSBOS implementation (from 3.34 to 3.17, p = 0.067). DISCUSSION: Crossmatching fewer RBC units facilitates more efficient management of the blood bank's inventory. CONCLUSION: The dMSBOS was effective in reducing the extent of unnecessary pre-transfusion testing before surgery and reduced the number of RBCs that were crossmatched for specific patients.

Intercalant-independent transition temperature in superconducting black phosphorus.

Research on black phosphorus has been experiencing a renaissance over the last years, after the demonstration that few-layer crystals exhibit high carrier mobility and a thickness-dependent bandgap. Black phosphorus is also known to be a superconductor under high pressure exceeding 10 GPa. The superconductivity is due to a structural transformation into another allotrope and accompanied by a semiconductor-metal transition. No superconductivity could be achieved for black phosphorus in its normal orthorhombic form, despite several reported attempts. Here we describe its intercalation by several alkali metals (Li, K, Rb and Cs) and alkali-earth Ca. All the intercalated compounds are found to be superconducting, exhibiting the same (within experimental accuracy) critical temperature of 3.8±0.1 K and practically identical characteristics in the superconducting state. Such universal superconductivity, independent of the chemical composition, is highly unusual. We attribute it to intrinsic superconductivity of heavily doped individual phosphorene layers, while the intercalated layers of metal atoms play mostly a role of charge reservoirs.

Effect of plasma surface treatment of poly(dimethylsiloxane) on the permeation of pharmaceutical compounds / 药物分析学报

This paper addresses the modification of poly(dimethylsiloxane), i.e. PDMS, using plasma surface treatment and a novel application of the membrane created. A set of model compounds were analysed to determine their permeation through PDMS, both with and without plasma treatment. It was found that plasma treatment reduced permeation for the majority of compounds but had little effect on some compounds, such as caffeine, with results indicating that polarity plays an important role in permeation, as is seen in human skin. Most importantly, a direct correlation was observed between plasma-modified permeation data and literature data through calculation of membrane permeability (Kp) values suggesting plasma-modified silicone membrane (PMSM) could be considered as a suitable in vivo replacement to predict clinical skin permeation.

Effect of plasma surface treatment of poly(dimethylsiloxane) on the permeation of pharmaceutical compounds / 药物分析学报

This paper addresses the modification of poly(dimethylsiloxane), i.e. PDMS, using plasma surface treatment and a novel application of the membrane created. A set of model compounds were analysed to determine their permeation through PDMS, both with and without plasma treatment. It was found that plasma treatment reduced permeation for the majority of compounds but had little effect on some compounds, such as caffeine, with results indicating that polarity plays an important role in permeation, as is seen in human skin. Most importantly, a direct correlation was observed between plasma-modified permeation data and literature data through calculation of membrane permeability (Kp) values suggesting plasma-modified silicone membrane (PMSM) could be considered as a suitable in vivo replacement to predict clinical skin permeation.

Acute Respiratory Distress Syndrome in Burn Patients: A Comparison of the Berlin and American-European Definitions.

The purpose of this study was to compare the Berlin definition to the American-European Consensus Conference (AECC) definition in determining the prevalence of acute respiratory distress syndrome (ARDS) and associated mortality in the critically ill burn population. Consecutive patients admitted to our institution with burn injury that required mechanical ventilation for more than 24 hours were included for analysis. Included patients (N = 891) were classified by both definitions. The median age, % TBSA burn, and injury severity score (interquartile ranges) were 35 (24-51), 25 (11-45), and 18 (9-26), respectively. Inhalation injury was present in 35.5%. The prevalence of ARDS was 34% using the Berlin definition and 30.5% using the AECC definition (combined acute lung injury and ARDS), with associated mortality rates of 40.9 and 42.9%, respectively. Under the Berlin definition, mortality rose with increased ARDS severity (14.6% no ARDS; 16.7% mild; 44% moderate; and 59.7% severe, P < 0.001). By contrast, under the AECC definition increased mortality was seen only for ARDS category (14.7% no ARDS; 15.1% acute lung injury; and 46.0% ARDS, P < 0.001). The mortality of the 22 subjects meeting the AECC, but not the Berlin definition was not different from patients without ARDS (P = .91). The Berlin definition better stratifies ARDS in terms of severity and correctly excludes those with minimal disease previously captured by the AECC.

Monitoring real time polymorphic transformation of sulfanilamide by diffuse reflectance visible spectroscopy$ / 药物分析学报

This study investigated the development of a novel approach to surface characterization of drug poly-morphism and the extension of the capabilities of this method to perform ‘real time’ in situ measure-ments. This was achieved using diffuse reflectance visible (DRV) spectroscopy and dye deposition, using the pH sensitive dye, thymol blue (TB). Two polymorphs, SFN-β and SFN-γ, of the drug substance sul-fanilamide (SFN) were examined. The interaction of adsorbed dye with polymorphs showed different behavior, and thus reported different DRV spectra. Consideration of the acid/base properties of the morphological forms of the drug molecule provided a rationalization of the mechanism of differential coloration by indicator dyes. The kinetics of the polymorphic transformation of SFN polymorphs was monitored using treatment with TB dye and DRV spectroscopy. The thermally-induced transformation fitted a first-order solid-state kinetic model (R2 ? 0.992), giving a rate constant of 2.43 ? 10 ? 2 s ? 1.

Excessive quantities of red blood cells are issued to the operating room.

OBJECTIVES: To determine what percentage of red blood cell (RBC) units that were issued to the operating room (OR) were returned unused, and to determine how often all of the RBCs that were issued for a patient were returned unused using the institution's maximum surgical blood ordering schedule (MSBOS) as a guide. BACKGROUND: The MSBOS provides guidelines for blood ordering, but is merely a suggestion for the ordering clinicians. This study examined how closely ordering practices followed the MSBOS, and how often ordered RBCs were actually transfused. METHODS: For a 4-week period, RBC issue and utilization data were collected on elective surgery patients who were eligible for electronic cross-match at a tertiary care hospital. These data were compared to the MSBOS. RESULTS: There were 1350 surgical procedures performed. Of these cases, 439 patients had a type and screen (T&S) performed, and 215/439 (49%) patients had at least 1 RBC issued during their case. To these 215 patients, 742 RBC units were issued and 537/742 (72%) of these units were returned to the blood bank unused. In 152/215 (71%) cases with issued RBCs, all of the RBCs were returned to the blood bank unused. Amongst the surgical categories in this study, the percentage of cases where none of the issued RBCs were transfused ranged from 38 to 93%. CONCLUSIONS: Significant numbers of RBC units are issued but not transfused during surgery. Involving the surgical team in the blood issuing process and using a data-driven MSBOS may reduce the number of unused units.