bluuebunny/crossref_metadata_2025 huggingface dataset:
Clustering of large‐scale circulation patterns during tropical cyclone preformation period using self‐organizing maps
Authors: Wang Zi‐Qing , Chen Guang‐Hua , Zhao Yu‐Hui
Published: March 2022

Based on self‐organizing maps (SOM), clustering analysis is performed on the lower‐level large‐scale flow fields centred at the tropical cyclone (TC) genesis points averaged over the 24‐hr TC preformation period. A total of 461 TCs over the western North Pacific (WNP) from June to November in 2000–2019 are classified into five patterns, that is, convergence (CON) pattern, monsoon trough (MT) pattern, pre‐existing cyclone (PC) pattern, subtropical high (SH) pattern and easterly wave (EW) pattern. The most frequent and southmost pattern, the CON pattern, is characterized by a confluent zone of monsoonal southwesterly flows and easterly flows. The second dominant pattern, the MT pattern, occurs the westmost and has a larger cyclonic vorticity in the strongest monsoon trough among the five patterns. In contrast, cyclogenesis in the SH pattern is featured by both the confluent zone and the cyclonic wind shear largely attributed to the subtropical high. The PC pattern features a pre‐existing cyclone to the northwest. The EW pattern with easterly flows in all four adjacent quadrants has the smallest number of TC formation and relatively northeast genesis location. Statistics also shows that the CON pattern dominates in late season, while the other four mainly appear in summertime. Large‐scale environmental conditions are quantified and comparisons with previous studies are also discussed.
Atmospheric and oceanic conditions associated with early and late onset for Eastern Africa short rains
Authors: Gudoshava Masilin , Wainwright Caroline , Hirons Linda , Endris Hussen S. , Segele Zewdu T. , Woolnough Steve , Atheru Zachary , Artan Guleid
Published: March 2022

Timing of the rainy season is essential for a number of climate sensitive sectors over Eastern Africa. This is particularly true for the agricultural sector, where most activities depend on both the spatial and temporal distribution of rainfall throughout the season. Using a combination of observational and reanalysis datasets, the present study investigates the atmospheric and oceanic conditions associated with early and late onset for Eastern Africa short rains season (October–December). Our results indicate enhanced rainfall in October and November during years with early onset and rainfall deficit in years with late onset for the same months. Early onset years are found to be associated with warmer sea surface temperatures (SSTs) in the western Indian Ocean, and an enhanced moisture flux and anomalous low‐level flow into Eastern Africa from as early as the first dekad of September. The late onset years are characterized by cooler SSTs in the western Indian Ocean, anomalous westerly moisture flux and zonal flow limiting moisture supply to the region. The variability in onset date is separated into the interannual and decadal components, and the links with SSTs and low‐level circulation over the Indian Ocean basin are examined separately for both timescales. Significant correlations are found between the interannual variability of the onset and the Indian Ocean dipole mode index. On decadal timescales the onset is shown to be partly driven by the variability of the SSTs over the Indian Ocean. Understanding the influence of these potentially predictable SST and moisture patterns on onset variability has huge potential to improve forecasts of the East African short rains. Improved prediction of the variability of the rainy season onset has huge implications for improving key strategic decisions and preparedness action in many sectors, including agriculture.
Amniotic membrane attenuates heterotopic ossification following high‐dose bone morphogenetic protein‐2 treatment of segmental bone defects
Authors: Priddy Lauren B. , Krishnan Laxminarayanan , Hettiaratchi Marian H. , Karthikeyakannan Sukhita , Gupte Nikhil , Guldberg Robert E.
Published: March 2022

Treatment of large bone defects with supraphysiological doses of bone morphogenetic protein‐2 (BMP‐2) has been associated with complications including heterotopic ossification (HO), inflammation, and pain, presumably due to poor spatiotemporal control of BMP‐2. We have previously recapitulated extensive HO in our rat femoral segmental defect model by treatment with high‐dose BMP‐2 (30 μg). Using this model and BMP‐2 dose, our objective was to evaluate the utility of a clinically available human amniotic membrane (AM) around the defect space for guided bone regeneration and reduction of HO. We hypothesized that AM surrounding collagen sponge would attenuate heterotopic ossification compared with collagen sponge alone. In vitro, AM retained more BMP‐2 than a synthetic poly(ε‐caprolactone) membrane through 21 days. In vivo, as hypothesized, the collagen + AM resulted in significantly less heterotopic ossification and correspondingly, lower total bone volume (BV), compared with collagen sponge alone. Although bone formation within the defect was delayed with AM around the defect, by 12 weeks, defect BVs were equivalent. Torsional stiffness was significantly reduced with AM but was equivalent to that of intact bone. Collagen + AM resulted in the formation of dense fibrous tissue and mineralized tissue, while the collagen group contained primarily mineralized tissue surrounded by marrow‐like structures. Especially in conjunction with high doses of growth factor delivered via collagen sponge, these findings suggest AM may be effective as an overlay adjacent to bone healing sites to spatially direct bone regeneration and minimize heterotopic ossification.
Study on gel properties of lysozyme‐free egg white before and after Lactiplantibacillus plantarum fermentation
Authors: Chen Jie , Wang Jing , Xu Lilan , Lv Yuanqi , Tang Tingting , Zhang Ming , Li Junhua , Su Yujie , Gu Luping , Yang Yanjun , Chang Cuihua
Published: March 2022

BACKGROUND

Isolation of lysozyme from egg white (EW) using ion exchange resin adsorption method generates large quantities of lysozyme‐free egg white (LFEW) with poor gelling property. To maximize the applications of LFEW, the effect of Lactiplantibacillus plantarum fermentation on the gel properties of LFEW was investigated in this study.

RESULTS

The fermentation efficiency of LFEW with lysozyme removed was significantly improved, and the sugar removal rate (2 g kg−1 Lactiplantibacillus plantarum, 37 °C, 7 h) was more than 90%. Removal of lysozyme resulted in increased stability and surface hydrophobicity of EW. After Lactiplantibacillus plantarum fermentation, the stability of EW decreased, and the average particle size and surface hydrophobicity increased. In addition, by comparing the gel properties of EW and LFEW before and after fermentation at different pH, it was found that the hardness, elasticity, and water holding capacity (WHC) of EW gel increased significantly. The removal of lysozyme effectively improved the WHC and springiness of the EW gel and promoted the formation of a denser network structure with smaller pores. After Lactiplantibacillus plantarum fermentation treatment, LFEW gel hardness decreased, with loose and porous network structure, no browning occurred after autoclaving.

CONCLUSION

This study provided the direction and theoretical basis for producing a fermented LFEW gel with pleasing texture and appearance. © 2022 Society of Chemical Industry.
Ultra high performance liquid chromatography with quadrupole time‐of‐flight tandem mass spectrometry and liquid chromatography with tandem mass spectrometry combined with chemometric analysis as an approach for the quality evaluation of Mume Fructus
Authors: Wang Rui , Cheng He , Yang Yatian , Ou Jinmei , Song Qianqian , Zhou Huiyin , Peng Huasheng , Wang Junfei , Fang Cheng Wu
Published: March 2022

Mume Fructus is an important traditional Chinese medicine that has been widely used in the treatment of intestinal diseases and asthma for thousands of years. In order to evaluate the quality of Mume Fructus in different processing methods, the main chemical components in Mume Fructus were investigated and a method was established for simultaneous quantification of organic acids of Mume Fructus. First, an optimized ultra‐performance liquid chromatography‐quadrupole‐time of flight tandem‐mass spectrometry method was used to identify the structures of main components in Mume Fructus. A total of 41 chemical compounds were identified, including 11 organic acids, 13 flavonoids, and three fatty acids. The contents of 11 organic acids in 18 batches of Mume Fructus from different processing methods were simultaneously determined by a liquid chromatography with tandem mass spectrometry method. The results of quantitative and hierarchical cluster analysis indicated that Mume Fructus under different processing methods were rich in the above 11 organic acids and the contents were obviously different. Taken together, the proposed quality evaluation method was fast and comprehensively reflects the content of the main chemical components in Mume Fructus under different processing methods, and provides a useful reference for the quality control and evaluation of Mume Fructus.
Spatial heterogeneity of ecosystem services trade‐offs among ecosystem service bundles in an alpine mountainous region: A case‐ study in the Qilian Mountains, Northwest China
Authors: Teng Yanmin , Zhan Jinyan , Liu Wei , Chu Xi , Zhang Fan , Wang Chao , Wang Lanyuan
Published: March 2022

In mountainous areas with diverse climate, topography, and socio‐economic status, ecosystem services (ES) trade‐offs may differ largely in space. However, few researches have spatially identified the trade‐offs and influencing factors of ES in different regions. We selected the Qilian Mountains (QLM) as a study area and eight key ES [grain production (GP), livestock production (LP), water yield (WY), carbon sequestration (CS), water erosion prevention (WAEC), wind erosion prevention (WIEC), habitat quality (HQ), and sightseeing (SS)] were evaluated through spatially explicit models. K‐means clustering was used to identify the ES bundles. Trade‐offs between ES were identified using factor analysis. Natural and human drivers that influence the spatial differentiation of ES were explored through redundancy analysis. The results showed the eight ES had obvious spatial heterogeneity and could be clustered into three bundles. In the entire QLM, there were obvious synergies between most ES, especially GP, LP, CS, and SS. However, several trade‐offs existed in different bundles (e.g., HQ with GP, LP, CS, and SS in bundle 1; HQ with GP, LP, and SS in bundle 2; WIEC with WY and WAEC in bundle 3). Natural factors were the main factors affecting the spatial differentiation of ES, among which vegetation coverage, elevation, precipitation, and slope have higher explanatory degrees, but differences among three bundles were great. The influence of human factors on the provisioning and cultural services was relatively high in local areas. This study can provide references for formulating regional development strategies in the QLM and other mountainous regions.
Step‐Growth Polymerized Systems of General Type “AfiBgi”: A Method to Calculate the Bivariate (Molecular Size) × (Path Length) Distribution
Authors: Hillegers L. Tom , Slot Johan J. M.
Published: March 2022

Step‐growth polymerized systems of general type “AfiBgi” are considered. The monomers bear one or more reactive groups of type A and/or B. An A group on one monomeric unit might react with a B group on another unit, thus coupling the two units. This process repeats itself randomly, and at a given degree of conversion, a wide range of polymeric molecules has formed, differing in both molecular size and in branching structure, determined by the laws of probability. In a slice of the molecular size distribution, all polymeric molecules have the same size, but differ in number and position of branching points. A method is presented to calculate the path length distribution for each such slice. Here, path length is the number of chemical bonds in the path connecting two monomeric units in the molecule. From the path length distribution, the light scattering function is calculated.
Ghost Fishing by Abandoned Trotlines in a Simulated and Actual Reservoir
Authors: McDonald Dusty L. , Schlechte J. Warren , Patterson Donovan A. , Binion Gregory R. , Boyles Amanda
Published: March 2022

Ghost fishing is described as the continuation of fishing by abandoned fishing gear. The freshwater trotline, a passive gear that is routinely found abandoned, has never been evaluated for its ability to ghost fish. We tested the effectiveness of top-water set trotlines to ghost fish in (1) a simulated reservoir (i.e., hatchery ponds) and (2) an actual reservoir. In our simulated reservoir, we exposed Channel Catfish Ictalurus punctatus to baited and bare (unbaited) hooks of two hook styles (circle and “J”) during the winter and summer seasons. We found that in the simulated reservoir, catch rates of baited hooks (mean = 18.4 fish per 24 hooks, standard error [SE] = 2.13) did not differ significantly from bare hooks (mean = 15.3 fish per 24 hooks, SE = 1.77), circle hooks were 1.5 times more effective at catching fish than “J” hooks (χ2 = 4.19, df = 1, P = 0.041), and fish were retained longer in the winter (mean = 12.7 d, SE = 0.66) compared to the summer (mean = 2.8 d, SE = 0.21). We used the actual reservoir portion to examine the long-term fishability and the overall longevity of the trotline gear during the same seasons. Catch was highest during the first week and decreased with time. Trotlines caught mostly fish (81.6%), and most catch (>68%) occurred after the initial bait was lost. Winter-set trotlines captured more organisms (11.6 per 25-hook trotline; SE = 2.05) than summer-set trotlines (5.2; SE = 0.99). Trotline longevity was assessed by counting the fishable hooks through time. Longevity differed between seasons (P = 0.0039), and winter-set trotlines lasted longer (50% hook loss at 52 d, 95% confidence interval [CI] = [49, 77]) than summer-set trotlines (32 d, 95% CI = [24, 36]). This study confirms that abandoned freshwater trotlines do ghost fish and will continue for months after they are initially set.
Introduction
Authors: Axelsson Bodil , Cameron Fiona R. , Hauptman Katherine , Pietrobruno Sheenagh
Published: March 2022

Curatorial agency is situated in the introduction via an elaboration of the intersection between the mission of public museums to care for collections and their increased reliance on digital capitalism’s social, technical and material infrastructures for the circulation of digitisations, narratives and new research findings. We explain how this book approaches curatorial agency in four individually authored chapters, each taking its own approach to museum knowledge and curatorial agency in regard to the junction of humanistic interpretations and new materialist and posthuman frameworks. Moreover, we explain how each chapter acts as a case study that tracks objects from the Swedish History Museum’s Viking Age collection to distinct technological spheres: Swedish discussion forums, YouTube, Pinterest and the vast infrastructures and destructive processes of Technospheric curation.
Tales of the Viking Helmet: Narrative Shifts from Museum Exhibitions to Personalised Search Requests
Authors: Pietrobruno Sheenagh
Published: March 2022

The stories of museum objects on YouTube can counter and support those advanced by museums. How the narratives of the Viking helmet on YouTube reflect or differ from those put forward by the Swedish History Museum’s Viking exhibitions is approached through a previous methodological study that investigated the issue of location in the personalisation of historical narratives of museum objects on YouTube search engine result pages (SERPs) (Pietrobruno 2021). This revised method combining language with location brings together two media forms—actual museum exhibitions and personalised YouTube SERPs. The philosophy behind their interconnection is rooted in how the personalised content of SERPs produce meaning and museum exhibitions employ forms of individual customisation to generate meaning by enabling visitors to personalise their exhibition experience.
Conclusion
Authors: Axelsson Bodil , Cameron Fiona R. , Hauptman Katherine , Pietrobruno Sheenagh
Published: March 2022

In this conclusion, we revisit some of the key findings of this book’s analytical/interpretative cuts into the online circulation of museum collections. The pedagogical challenges museums face when collection knowledge is appropriated by groups whose political aims threaten social solidarity and democratic values are discussed. Highlighted are the ways in which collection knowledge is both customised and open-ended when digitisations, narratives and research findings flow between multiple platforms and are transmitted through interfaces including home feeds or lists. We conclude that curatorial agency simultaneously becomes humanist and subjective; machinic and computational; and imbricated in more-than-human ontological formations that insert digitisations and museum knowledge in multi-scalar geographies and temporalities extending from deep geological time into unforeseen futures.
Interannual Variations of Submesoscale Circulations in the Subtropical Northeastern Pacific
Authors: Sasaki Hideharu , Qiu Bo , Klein Patrice , Nonaka Masami , Sasai Yoshikazu
Published: March 2022

Impacts of oceanic submesoscale circulations on oceanic circulation as well as marine ecosystem and air‐sea heat flux have been reported by recent studies. Therefore, their regionality and variations on various timescales are important to understand their impacts. The submesoscale circulations are active in winter, which is mostly enhanced by mixed layer instability (MLI). However, their variations on timescales longer than interannual are not well understood. This study shows the interannual variations of active submesoscale circulations in winter and their mechanism in the subtropical northeastern Pacific using the output of a submesoscale permitting simulation. The submesoscale kinetic energy varies synchronously with the available potential energy release in a process of MLI. El Niño events appear to modulate the interannual variations. In addition, the similarities and differences between the variations in the eastern and western subtropics are highlighted.
Impacts of Land Use Change and Atmospheric CO2 on Gross Primary Productivity (GPP), Evaporation, and Climate in Southern Amazon
Authors: Rezende Luiz F. C. , de Castro Aline Anderson , Von Randow Celso , Ruscica Romina , Sakschewski Boris , Papastefanou Phillip , Viovy Nicolas , Thonicke Kirsten , Sörensson Anna , Rammig Anja , Cavalcanti Iracema F. A.
Published: March 2022

Recent publications indicate that the Amazon may be acting more as a carbon source than a sink in some regions. Moreover, the Amazon is a source of moisture for other regions in the continent, and deforestation over the years may be reducing this function. In this work, we analyze the impacts of elevated CO2 (eCO2) and land use change (LUC) on gross primary productivity (GPP) and evaporation in the southern Amazon (7°S 14°S, 66°W 51°W), which suffered strong anthropogenic influence in the period of 1981‒2010. We ran four dynamic global vegetation models (DGVMs), isolating historical CO2, constant CO2, LUC, and potential natural vegetation scenarios with three climate variable data sets: precipitation, temperature, and shortwave radiation. We compared the outputs to five “observational” data sets obtained through eddy covariance, remote sensing, meteorological measurements, and machine learning. The results indicate that eCO2 may have offset deforestation, with GPP increasing by ∼13.5% and 9.3% (dry and rainy seasons, respectively). After isolating the LUC effect, a reduction in evaporation of ∼4% and ∼1.2% (dry and rainy seasons, respectively) was observed. The analysis of forcings in subregions under strong anthropogenic impact revealed a reduction in precipitation of ∼15 and 30 mm, and a temperature rise of 1°C and 0.6°C (dry and rainy seasons, respectively). Differences in the implementation of plant physiology and leaf area index in the DGVMs introduced some uncertainties in the interpretation of the results. Nevertheless, we consider that it was an important exercise given the relevance.
Development and Evaluation of Near‐Real Time TEC and Ancillary Products for SANSA Space Weather
Authors: Matamba Tshimangadzo M. , Danskin Donald W.
Published: March 2022

In this paper, the second version of SANSA's Total Electron Content (TEC) maps is presented with its associated methodology and assumptions. The method is based on Ma and Maruyama (2003, https://doi.org/10.5194/angeo-21-2083-2003) determination of receiver bias and hence TEC for individual receivers. By combining values of slant TEC from 20 South African Trignet stations, maps of TEC, spatial gradient of TEC and temporal gradient of TEC can be determined. Quality factors and error of fit are determined for each map and are analyzed to identify the level of validity for TEC maps. In addition, the first operational estimation of TEC gradients both temporal and spatial are presented and discussed for the 4–5 November 2021 negative ionospheric storm. The TEC from the maps shows good agreement with the ionosonde TEC and AfriTEC model.
Deep-Sea Exploration Could Help Us Fight the Next Pandemic
Authors: Robinson Nathan
Published: March 2022

Deep-ocean-dwelling microbes may hold keys to improved medical diagnostics and new drugs for fighting diseases. But we must search Earth’s most extreme habitats to find them.
Exploring Subduction Zone Geohazards on Land and at Sea
Authors: Huang Mong-Han , Morell Kristin , Duvall Alison , Gallen Sean , Hilley George
Published: March 2022

A new initiative is bringing together scientists to address fundamental questions about subduction zone geohazards, using the latest advances in observation technology and computational resources.
Coalescence Scavenging Drives Droplet Number Concentration in Southern Ocean Low Clouds
Authors: Kang L. , Marchand R. T. , Wood R. , McCoy I. L.
Published: March 2022

Cloud droplet number concentration (Nd) is a key microphysical property that is largely controlled by the balance between sources and sinks of aerosols that serve as cloud condensation nuclei (CCN). Despite being a key sink of CCN, the impact of coalescence scavenging on Southern Ocean (SO) cloud is poorly known. We apply a simple source‐and‐sink budget model based on parameterizations to austral summer aircraft observations to test model behavior and examine the relative influence of processes that determine Nd in SO stratocumulus clouds. The model predicts Nd with little bias and a correlation coefficient of ∼0.7 compared with observations. Coalescence scavenging is found to be an important sink of CCN in both liquid and mixed‐phase precipitating stratocumulus and reduces the predicted Nd by as much as 90% depending on the precipitation rate. The free tropospheric aerosol source controls Nd more strongly than the surface aerosol source during austral summer.
The Curious Relationship Between COVID‐19 Lockdowns and Urban Heat Islands
Authors: Shepherd Marshall
Published: March 2022

The COVID‐19 pandemic has been a life‐altering shock to society. However, there have been serendipitous outcomes from the associated lockdowns ranging from improved air quality to reductions in carbon emissions. Liu et al. (2022, https://doi.org/10.1029/2021GL096842) revealed that even the magnitude of the heat islands in Chinese cities were reduced due to a decline in human activities and their associated anthropogenic contributions. These surprising findings have significant implications for understanding intersections among climate, health, energy, urban planning, transportation, and infrastructure.
Deviation of Mercury's Spin Axis From an Exact Cassini State Induced by Dissipation
Authors: MacPherson Ian , Dumberry Mathieu
Published: March 2022

We compute predictions of the deviation of Mercury's spin axis from an exact Cassini state caused by tidal dissipation as well as viscous and electromagnetic (EM) friction at the core‐mantle boundary (CMB) and inner core boundary (ICB). Viscous friction at the CMB generates a phase lead; viscous and EM friction at the ICB produce a phase lag; the magnitude of the deviation depends on the inner core size, kinematic viscosity, and magnetic field strength, but cannot exceed an upper bound. For a small inner core, viscous friction at the CMB results in a maximum phase lead of 0.027 arcsec. For a large inner core (radius >1,000 km), EM friction at the ICB generates the largest phase lag, but it does not exceed 0.1 arcsec. Elastic deformations induced by the misaligned fluid and solid cores play a first‐order role in the phase lead/lag caused by viscous and EM coupling and contribute to a perturbation in mantle obliquity on par with that caused by tidal deformations. Tidal dissipation results in a phase lag and its magnitude (in units of arcsec) is given by the empirical relation (80/Q), where Q is the quality factor; Q = 80 results in a phase lag of ∼1 arcsec. A large inner core with a low viscosity of the order of 1017 Pa s or lower can significantly affect Q and thus the resulting phase lag. The limited mantle phase lag suggested by observations (<10 arcsec) implies a lower limit on the bulk mantle viscosity of approximately 1017 Pa s.
A flexible Bayesian framework for unbiased estimation of timescales
Authors: Zeraati Roxana , Engel Tatiana A. , Levina Anna
Published: March 2022

Timescales characterize the pace of change for many dynamic processes in nature. They are usually estimated by fitting the exponential decay of data autocorrelation in the time or frequency domain. Here we show that this standard procedure often fails to recover the correct timescales due to a statistical bias arising from the finite sample size. We develop an alternative approach to estimate timescales by fitting the sample autocorrelation or power spectrum with a generative model based on a mixture of Ornstein–Uhlenbeck processes using adaptive approximate Bayesian computations. Our method accounts for finite sample size and noise in data and returns a posterior distribution of timescales that quantifies the estimation uncertainty and can be used for model selection. We demonstrate the accuracy of our method on synthetic data and illustrate its application to recordings from the primate cortex. We provide a customizable Python package that implements our framework via different generative models suitable for diverse applications.
Leaf temperature and CO
Authors: Greer Dennis H.
Published: March 2022

Responses of CO2 assimilation and chlorophyll a fluorescence to light intensity for Shiraz leaves on vines grown outdoors were examined in relation to leaf temperature. The study aimed to assess whether perturbing the carbon source, by manipulating short-term CO2 concentrations, would affect photosynthetic responses to temperature. Strong interactions occurred between leaf temperature and CO2 on photosynthetic and electron transport light responses. Most responses to temperature occurred at low to moderate CO2 and little response to temperature occurred at high CO2. While assimilation responses accorded with increasing substrate CO2, electron transport was inhibited by elevated CO2. By contrast, chlorophyll a fluorescence was not affected by a temperature × CO2 interaction and CO2 had no effect on PSII quantum efficiency or photochemical quenching; whereas there was a moderate effect of temperature. Quantum efficiency of PSII was most severely reduced at low temperatures. Most photochemical quenching also occurred at low temperatures and the least at 40°C, in keeping with the warm to hot growth climate and the apparent assimilation bias towards the higher temperatures of the growing season. No changes in temperature dependency of assimilation were detected at the different CO2 concentrations, confirming sinks have a greater effect on assimilation than does the source.
Overview of the roles of calcium sensors in plants’ response to osmotic stress signalling
Authors: Ketehouli Toi , Nguyen Quoc Viet Hoang , Dong Jinye , Do Hoaithuong , Li Xiaowei , Wang Fawei
Published: March 2022

Calcium signals serve an important function as secondary messengers between cells in various biological processes due to their robust homeostatic mechanism, maintaining an intracellular free Ca2+ concentration. Plant growth, development, and biotic and abiotic stress are all regulated by Ca2+ signals. Ca2+ binding proteins decode and convey the messages encoded by Ca2+ ions. In the presence of high quantities of Mg2+ and monovalent cations, such sensors bind to Ca2+ ions and modify their conformation in a Ca2+-dependent manner. Calcium-dependent protein kinases (CPKs), calmodulins (CaMs), and calcineurin B-like proteins are all calcium sensors (CBLs). To transmit Ca2+ signals, CPKs, CBLs, and CaMs interact with target proteins and regulate the expression of their genes. These target proteins may be protein kinases, metabolic enzymes, or cytoskeletal-associated proteins. Beyond its role in plant nutrition as a macroelement and its involvement in the plant cell wall structure, calcium modulates many aspects of development, growth and adaptation to environmental constraints such as drought, salinity and osmotic stresses. This review summarises current knowledge on calcium sensors in plant responses to osmotic stress signalling.
Morphometric similarity deviations in stimulant use disorder point towards abnormal brain ageing
Authors: Zhukovsky Peter , Savulich George , Morgan Sarah , Dalley Jeffrey W. , Williams Guy B. , Ersche Karen D.
Published: March 2022

Chronic drug use negatively impacts ageing, resulting in diminished health and quality of life. However, little is known about biomarkers of abnormal ageing in stimulant drug users. Using morphometric similarity network mapping, a novel approach to structural connectomics, we first mapped cross-sectional morphometric similarity trajectories of ageing in the publicly available Rockland Sample (20–80 years of age, n = 665). We then compared morphometric similarity and neuropsychological function between non-treatment-seeking, actively using patients with stimulant use disorder (n = 183, mean age: 35.6 years) and healthy control participants (n = 148, mean age: 36.0 years). The significantly altered mean regional morphometric similarity was found in 43 cortical regions including the inferior and orbital frontal gyri, pre/postcentral gyri and anterior temporal, superior parietal and occipital areas. Deviations from normative morphometric similarity trajectories in patients with stimulant use disorder suggested abnormal brain ageing. Furthermore, deficits in paired associates learning were consistent with neuropathology associated with both ageing and stimulant use disorder. Morphometric similarity mapping provides a promising biomarker for ageing in health and disease and may complement existing neuropsychological markers of age-related cognitive decline. Neuropathological ageing mechanisms in stimulant use disorder warrant further investigation to develop more age-appropriate treatments for older people addicted to stimulant drugs.
Case Series of False-Positive HIV Test Results in Pediatric Acute Lymphoblastic Leukemia Patients Following Chimeric Antigen Receptor T-Cell Therapy: Guidance on How to Avoid and Resolve Diagnostic Dilemmas
Authors: Alali Muayad , Carlucci James G , Christenson John , Prather Cassandra , Skiles Jodi
Published: March 2022

Chimeric antigen receptor T-cell (CAR-T) Cell Therapy is approved for the treatment of pediatric patients with relapsed/refractory acute lymphoblastic leukemia B-ALL. Lentiviral vector technology, highly modified from HIV-1, is used to induce stable, long-term transgene expression by integration into the host genome. This integration may interfere with HIV-1 NAAT producing false-positive results. Guidance for HIV diagnostic testing in pediatric B-ALL undergoing this type of therapy is lacking. Herein, we report case series with presented scenarios in which HIV-1 NAAT testing among CAR-T cell patients produced false-positive results, highlighting the importance careful assay selection and performance among this patient population.
Headache and Facial Pain
Authors: Newman Lawrence , Levin Morris , Halker Rashmi , Michael Rebecca
Published: March 2022

This book explores 38 cases about headache and facial pain. In this edition, several scenarios that seem less important or less problematic as a result of new developments in the field have been eliminated. In addition, cases dealing with issues that were not included in the first edition have been added, and the rest of the cases have been revised and updated. The volume is divided into four sections that cover the typical ground for head and face pain consultation: Diagnostic Questions; Treatment Questions; Questions Related to Special Populations; and Prognostic, Social, and Legal Issues. Diagnostic reasoning is presented along the lines of the third edition of the International Classification of Headache Disorders. Moreover, a list of key clinical points appears at the end of each case discussion, followed by a list of suggested articles or chapters for those interested in doing further reading on the subject.
Orgasmic Headaches
Authors: Newman Lawrence C. , Levin Morris , Halker Singh Rashmi B. , Michael Rebecca L.
Published: March 2022

A severe abrupt headache occurring with exertion is suggestive of subarachnoid hemorrhage, other intracranial hemorrhage, or arterial dissection. Thus, it must be aggressively worked up. Recurring exertional or sex-induced headaches are usually more benign. Nevertheless, it is imperative to rule out serious causes of ANY sudden or “thunderclap headache.” In this chapter, the wide range of possible causes of thunderclap headache is discussed, including both primary and secondary causes. A parsimonious diagnostic path is outlined, aimed at quickly discovering dangerous causes of these headaches. Treatment options for orgasmic headache are also presented.
Sinus Headache
Authors: Newman Lawrence C. , Levin Morris , Halker Singh Rashmi B. , Michael Rebecca L.
Published: March 2022

Migraine and other primary headache types are often misdiagnosed as “sinus headache” because of their sometimes midfrontal location and nasal/sinus symptoms. However, there are some rhinological and sinus conditions, such as inadequately treated sinusitis, that do lead to head and/or facial pain. Imaging can help but can also be misleading because some degree of paranasal sinus pathology is common. Imaging findings suggestive of sinus-related headaches include filling opacity in one or more sinus cavities; air–fluid levels in maxillary, ethmoid, frontal, or sphenoid sinuses; and evidence of bony changes involving the surrounding osseous structures. A more controversial cause of rhinological head pain—the “nasal contact point headache”—may be underdiagnosed. The causes and best approaches to diagnosing headache due to rhinosinusitis and related conditions are discussed in this chapter.
White Matter Abnormalities on Magnetic Resonance Imaging
Authors: Newman Lawrence C. , Levin Morris , Halker Singh Rashmi B. , Michael Rebecca L.
Published: March 2022

White matter hyperintensities (WMH) are a common incidental finding on brain magnetic resonance imaging (MRI). The prevalence of WMH increases with age, and they are also seen more commonly in individuals with hypertension, diabetes, hypercholesterolemia, cerebrovascular and cardiovascular disease, multiple sclerosis, and collagen vascular and other autoimmune disorders. Because the causes of WMH are so extensive, determining their etiology can be difficult. This chapter on white matter abnormalities on MRI provides a detailed discussion on the nonspecific T2 hyperintensities commonly seen on brain MRI in people who have migraine. The chapter discusses the differential diagnosis for this MRI finding, and it also reviews when to consider a workup for secondary causes.
Giant Cell Arteritis
Authors: Newman Lawrence C. , Levin Morris , Halker Singh Rashmi B. , Michael Rebecca L.
Published: March 2022

This chapter discusses giant cell arteritis (GCA), which affects medium and large arteries and is the most common primary vasculitis in adulthood. This inflammatory arteritis has its onset almost always after age 50 years, and the highest incidence occurs in the seventh and eighth decades of life. Clinically, GCA may present in a variety of ways, but headache is the most common initial symptom. Additional findings include abnormalities of the temporal artery (beading, prominence, tenderness, and pulselessness), jaw claudication, scalp tenderness, tongue or scalp necrosis, diplopia, elevated erythrocyte sedimentation rate (ESR), and visual changes. GCA can also cause a rapidly sequential, bilateral blindness. If GCA is considered likely by clinical history and physical examination, a workup demonstrating elevations in ESR and C-reactive protein should be done. Corticosteroids are considered the preferred treatment of GCA. Tocilizumab, an interleukin-6 receptor blocker, has been shown to lessen total steroid dosage and duration of steroid treatment.
Spontaneous Intracranial Hypotension
Authors: Newman Lawrence C. , Levin Morris , Halker Singh Rashmi B. , Michael Rebecca L.
Published: March 2022

This chapter evaluates spontaneous intracranial hypotension (SIH), which is a well-recognized syndrome that is characterized by orthostatic headaches in association with a variety of other symptoms. It results from an occult leakage of cerebrospinal fluid (CSF) through weakness of the dura from nerve root sleeves, dural rents caused by herniated discs or osteophytic microspurs, or by CSF-venous fistulas. In the majority of cases, the cause of SIH is unclear, but possible precipitants include a history of trivial trauma and weakness of the dural sac. The characteristic clinical feature of SIH is headache, which is usually throbbing, bilateral, and worsened by Valsalva maneuvers. The diagnosis of SIH may be established in several ways, but there is not a single modality that consistently reveals the answer. Treatment of SIH includes conservative measures such as bed rest and hydration and caffeine administration (by mouth or intravenously). Epidural blood patching may provide relief.
Migraine with Persistent Aura
Authors: Newman Lawrence C. , Levin Morris , Halker Singh Rashmi B. , Michael Rebecca L.
Published: March 2022

Approximately 20% of individuals with migraine experience an aura with their attacks. Auras are characterized by transient episodes of fully reversible focal neurological disturbances that may precede or accompany the headache onset. Occasionally, auras may occur without headache. In general, auras develop gradually over 5–20 minutes and resolve within 1 hour or less. The migraine aura may manifest as a visual, sensory, or language disturbance and may be simple or complex. This chapter on migraine with persistent aura defines migraine with aura and differentiates persistent aura from typical aura. The chapter provides tools to help with the diagnostic workup when a patient presents with persistent aura and also provides differential diagnosis and management recommendations.
Vestibular Migraine
Authors: Newman Lawrence C. , Levin Morris , Halker Singh Rashmi B. , Michael Rebecca L.
Published: March 2022

Vertigo and migraine have a number of associations. Vertigo is a relatively common, although generally mild, aura symptom in patients with migraine with aura. There are some migraine disorders with very prominent vertigo, such as basilar-type migraine and benign positional vertigo of childhood. Many patients with migraine suffer from motion sickness, including the visually induced variety. The diagnosis of vestibular migraine (previously termed migrainous vertigo) in the absence of the accompanying headache is challenging but crucial if these patients are to receive effective treatment. Criteria for diagnosing vestibular migraine are summarized in this chapter, and the overall differential diagnosis of vertigo is presented. Management of vestibular migraine is also reviewed.
Nummular Headache
Authors: Newman Lawrence C. , Levin Morris , Halker Singh Rashmi B. , Michael Rebecca L.
Published: March 2022

Nummular (“coin-shaped”) headache (NH) is characterized by generally continuous but usually not severe pain limited to a small area of the scalp. There can be sharp pains (lancinations) superimposed upon baseline aching pain. Diagnosing NH rests on identifying a small consistently located painful area in the scalp. The underlying pathophysiology is thought to be due to a local neuropathic process, perhaps akin to distal trigeminal or cervical root painful neuropathy. There is no definitive laboratory test for NH, and location can vary, although often the focal area is in the parietal scalp region. Pain can be bothersome, and treatment options (including local anesthetic procedures) are discussed in this chapter.
Thunderclap Headache
Authors: Newman Lawrence C. , Levin Morris , Halker Singh Rashmi B. , Michael Rebecca L.
Published: March 2022

This chapter discusses thunderclap headache, which is an excruciating headache that reaches maximal intensity in less than 1 minute. Given the potentially serious outcome of its possible underlying causes, thunderclap headache should always be considered a medical emergency. The initial diagnostic assessment must be focused on first ruling out subarachnoid hemorrhage with noncontrast computed tomography of the brain and lumbar puncture. Further diagnostic testing including magnetic resonance imagining of the brain with vascular imaging may be necessary. Treatment of thunderclap headache is dependent on the underlying etiology. If reversible cerebral vasoconstriction syndrome is diagnosed, indicated treatment is thought to include the calcium channel blockers nimodipine or verapamil, and possibly corticosteroids. If no underlying etiology is identified, a diagnosis of either primary thunderclap headache or primary cough, exertional, or sexual headache should be considered.
Trigeminal Neuralgia
Authors: Newman Lawrence C. , Levin Morris , Halker Singh Rashmi B. , Michael Rebecca L.
Published: March 2022

The pain of trigeminal neuralgia (TN) pain is typically lancinating but can include more long-lasting aching or burning pain as well. There are several categories of TN, and its differential diagnosis also includes a number of mimics, from pain of other nerve origin to local inflammatory or other disease and certain primary headache disorders. Determining the category into which a patient’s trigeminal pain fits can often lead to optimal treatment. Although prophylactic pharmacological treatment can usually prevent most pain due to TN, surgical options may be helpful in refractory cases. This chapter summarizes the appropriate workup of presumptive TN, including examination details and imaging testing, and presents best management approaches to refractory pain.
Headache and Allergy
Authors: Newman Lawrence C. , Levin Morris , Halker Singh Rashmi B. , Michael Rebecca L.
Published: March 2022

This chapter addresses the relationship between headache and allergy. Over-the-counter medications such as nonsteroidal anti-inflammatory drugs and, in particular, combination medications such as acetaminophen–aspirin–caffeine can lead to medication overuse headache, which can mimic chronic migraine. Food and other environmental allergies are rarely causes of headaches in the absence of other symptoms. Nonpharmacological therapies that are evidence-based include cognitive–behavioral therapy, relaxation techniques, and biofeedback. Biofeedback and massage have some support. Herbal/vitamin headache therapies that have some scientific support include magnesium, vitamin B2, feverfew, butterbur, and coenzyme Q10. The so-called energy therapies—including reiki, craniosacral therapy, qi gong, and meditation—are also proposed widely, but scientific support is not yet available.
Headache Treatment in Human Immunodeficiency Virus Infection
Authors: Newman Lawrence C. , Levin Morris , Halker Singh Rashmi B. , Michael Rebecca L.
Published: March 2022

This chapter describes headache treatment in human immunodeficiency virus (HIV) infection. Antivirals used in HIV-infected patients can lead to headaches. The virus can cause headaches itself, perhaps on the basis of active central nervous system infection or due to the fact that the metabolism of serotonin and tryptophan seems to be altered in HIV infection. However, primary headaches in patients with HIV infection are very common and usually not related to the antiretroviral drug therapy. In general, beta-blockers, tricyclic antidepressants, topiramate, and perhaps calcium channel blockers can make good choices in patients with HIV naïve to headache prophylactic treatment, but there are risks. One should carefully consider medication interactions as well as comorbidities when choosing the most appropriate acute and preventive medications in HIV patients on antiretroviral medications.
Idiopathic Intracranial Hypertension
Authors: Newman Lawrence C. , Levin Morris , Halker Singh Rashmi B. , Michael Rebecca L.
Published: March 2022

This chapter explores idiopathic intracranial hypertension (IIH), which is seen predominantly in obese women of childbearing age but can occur in other groups as well. Diagnosing IIH is based on elevated cerebrospinal fluid pressure as well as the characteristic features of global headache, pulsatile tinnitus, and papilledema. Differential diagnosis includes cerebral venous thrombosis, so magnetic resonance imaging should also include venography in atypical cases. Rheumatological and hormonal workup is also worthwhile because lupus and endocrinological disease can lead to increased intracranial pressure. The only morbidity in IIH is preventable visual loss, so close monitoring of visual acuity and visual fields is imperative. Moreover, because obesity is clearly a risk factor for IIH, weight loss in obese patients is considered a key treatment goal.
Postdural Puncture Headache
Authors: Newman Lawrence C. , Levin Morris , Halker Singh Rashmi B. , Michael Rebecca L.
Published: March 2022

This chapter discusses postdural puncture headache (PDPH), which may be the result of a lumbar puncture, myelogram, or an inadvertent dural puncture during neuraxial anesthesia. PDPH results from decreased cerebrospinal fluid volume from a leak at the dural puncture site, which causes sinking of the brain in the skull. This “brain sag” induces traction on the pain-sensitive suspending and anchoring structures of the brain and is responsible for the headaches and associated signs and symptoms of this disorder. These headaches are usually throbbing, bilateral, localized to the occipital or suboccipital areas, and worsened with Valsalva maneuvers. Because symptoms can spontaneously remit in the majority of patients within 2 weeks, the treatment of PDPH includes conservative measures such as bed rest and hydration, simple analgesics, and caffeine administration (by mouth or intravenously). If conservative measures fail, or in cases in which the pain and disability are high, epidural blood patching should be performed.