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The energy efficiency of emerging aircraft designs plays a key role, not only in reducing environmental impact, but also in reducing operating costs in the anticipated rise in fuel prices. The European Clean Sky 2 project HLFC-Win is investigating the feasibility of hybrid laminar flow control (HLFC) technology integrated into the outer wing leading edge for a long-haul aircraft. HLFC technology reduces aerodynamic friction drag by means of suction of the boundary layer through a micro-perforated skin to achieve laminarity and thereby improving aircraft performance. However, integrating such a system is not without its drawbacks, as the integration has an impact on the geometry, mass, aerodynamics and engine offtakes that need to be considered. Therefore, the aim of this current work is to assess the HLFC system based on a fair, objective and transparent comparison between the HLFC aircraft and an aircraft of the same technology level without HLFC. The assessment of the HLFC system is twofold, firstly estimating the mission-based performance at the overall aircraft level and secondly performing a lifecycle simulation with three scenarios to determine realistic fuel and cost savings. The mission-based performance assessment indicates a block fuel reduction of over 3 % for the design mission which averages 1.6 to 2.5 % considering a realistic route scenario and expected degradation. The economic assessment suggests a dependency on the scenario chosen, ranging from a 0.7 % increase in total cost (in an unfavourable scenario) to almost a 1 % reduction in total cost (in a favourable scenario), equivalent to $15 million saved per HLFC aircraft over its lifetime. These results support the commercial viability of HLFC technology, which offers significant aerodynamic and fuel efficiency improvements and operating cost savings to the aviation industry. Importantly, no critical barriers were identified for the integration of HLFC technology, further underscoring its potential to improve aircraft performance.
Burial 10 is a unique Manteño (AD 650–1532) burial from Buen Suceso, Ecuador, dating between AD 771 and 953. This burial included the remains of a young female, pregnant at the time of death and buried with an elaborate array of goods, including anachronistic spondylus ornaments, green stones, and shell eye coverings. Perimortem trauma, including a cranial fracture and cutmarks on hand bones, perimortem removal of the hands and left leg, and other body manipulation suggest she was sacrificed, a rare event for coastal Ecuadorian peoples.
This research examines how Beijing uses social media to publicize donations and engage in nation branding as it responds to the global backlash sparked by Covid-19. It argues that self-reports of medical donations aim to enhance China’s national brand, leading to an expectation that reports about donations will primarily target countries more severely affected by the virus. To test its claims, the research analyzes over 55,000 tweets published by Chinese diplomatic missions. The results—controlled for Chinese donation exports—show a positive and significant relationship between self-reports of medical donations and the host’s spread of Covid-19. In contrast, donations are not correlated with political or economic allies. A comparison of government (CCP, ministries, etc.) and non-government donors (immigrants, firms, etc.) shows that only donations by the latter are positively correlated with the spread of the virus. This research advances our knowledge of Chinese diplomats’ online political behavior.
This paper provides the details of a novel systematic design methodology for two-way in-phase filtering Gysel splitter/combiner networks with high selectivity, which finds application in high power amplifier modules. It simultaneously realizes a filtering function and a two-way splitter/combiner function. The proposed five-port filtering device, based on the Gysel topology, is transformed into a ring of coupled resonators. A rigorous coupling matrix describing the network is used to synthesize the integrated filtering and combining functions. This general network can be implemented in any of the available filter technologies. In this paper, a few design examples are provided, and a six-pole prototype utilizing compact combline coaxial resonators is demonstrated. The proposed design provides an integrated dual function module, reducing component counts and system complexity. A design was fabricated and tested demonstrating good experimental results.
Three-dimensional non-rotating odd viscous liquids give rise to Taylor columns and support axisymmetric inertial-like waves (J. Fluid Mech., vol. 973, 2023, A30). When an odd viscous liquid is subjected to rigid-body rotation however, there arise in addition a plethora of other phenomena that need to be clarified. In this paper, we show that three-dimensional incompressible or two-dimensional compressible odd viscous liquids, rotating rigidly with angular velocity $\varOmega$, give rise to both oscillatory and evanescent inertial-like waves or a combination thereof (which we call of mixed type) that can be non-axisymmetric. By evanescent, we mean that along the radial direction, typically when moving away from a solid boundary, the velocity field decreases exponentially. These waves precess in a prograde or retrograde manner with respect to the rotating frame. The oscillatory and evanescent waves resemble respectively the body and wall-modes observed in (non-odd) rotating Rayleigh–Bénard convection (J. Fluid Mech., vol. 248, 1993, pp. 583–604). We show that the three types of waves (wall, body or mixed) can be classified with respect to pairs of planar wavenumbers $\kappa$ which are complex, real or a combination, respectively. Experimentally, by observing the precession rate of the patterns, it would be possible to determine the largely unknown values of the odd viscosity coefficients. This formulation recovers as special cases recent studies of equatorial or topological waves in two-dimensional odd viscous liquids which provided examples of the bulk–interface correspondence at frequencies $\omega <2\varOmega$. We finally point out that the two- and three-dimensional problems are formally equivalent. Their difference then lies in the way data propagate along characteristic rays in three dimensions, which we demonstrate by classifying the resulting Poincaré–Cartan equations.
Delirium is common in hospital settings, with approximately 3% to 45% of older patients in hospitals developing delirium during their stay. Among the elderly and those with severe or advanced medical conditions, the reported percentage of patients with delirium is over 56%. The three motor subtypes of delirium are hyperactive, hypoactive, and mixed. Another way to characterize delirium is based on whether it is reversible, irreversible, or terminal.
Objectives
Identifying appropriate pharmacological treatment options among antipsychotics and their correlation with various precipitating and predisposing factors in the in-hospital context
Methods
This was a retrospective, cross-sectional, observational study that utilized a database created by the psychiatry department at the National Medical Center 20 de Noviembre, with data collected from April 2021 to April 2022. The database contains anonymized administrative and clinical data of patients who were seen in the psychiatry department for the diagnosis of any type of delirium, using the CAM scale for classification. The database includes records and data of hospitalized patients, encompassing all specialties at this medical center
Results
A total of 139 patients were included in the study, of which 39% were female and 61% were male, with a mean age of 67 and a median age of 68 years. It was observed that the average duration of delirium symptoms, from receiving the consultation to remission, was approximately 6 days (p <0.005) (OR 5.12-6.62), and the average length of hospital stay was approximately 20 days (OR 17.3-22.09). Among the patients, 50.39% were overweight, 63% had hypertension (HTA), 29% had chronic kidney injury, 24% had a history of delirium, and 73% had recent surgical interventions. Patients with diabetes mellitus had a 3.1 times higher risk, those with HTA had a 2.8 times higher risk, and those with kidney injury had a 3.8 times higher risk of having a positive CAM result. It was observed that haloperidol, used in 84% of the patients, showed the highest percentage reduction in CAM scores
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Conclusions
The results of this study emphasize the importance of identifying risk factors associated with delirium and implementing effective treatment for this condition. It was observed that the average duration of delirium symptoms was approximately 6 days, which is relevant for understanding the course and management of this illness. Furthermore, it was found that the average hospital stay was 20 days, underscoring the burden that delirium can place on healthcare systems.
In conclusion, this study highlights the importance of identifying risk factors and providing appropriate treatment, such as the use of haloperidol, to improve outcomes in patients with delirium.
A number of studies have demonstrated that hyperthyroidism increases the prevalence of psychiatric disorders and the likelihood of depressive symptoms, anxiety and hipomania. Apathetic hyperthyroidism is a syndrome, which presents with symptoms of depression, apathy, somnolence or pseudodementia in the absence of the usual symptoms and signs of hyperthyroidism. This condition is more common in the elderly although it has also been described in young adults and adolescents.
In the majority of cases, treatment of hyperthyroidism results in an improvement in neuropsychiatric manifestations in parallel with an improvement of psychical (somatic?) symptoms and psychotropic medication is deemed unnecessary.
Approximately one-third of patients with Graves’ hyperthyroidism are prescribed psychotropic drugs. Sometimes to treat mental symptoms like psychosis or severe agitation, sometimes to treat mental symptoms remaining after amelioration of hyperthyroidism, and sometimes when the diagnosis of Graves’ hyperthyroidism has been missed and the patient is treated as having a primary psychiatric disorder.
Objectives
To present a case of a patient with neuropsychiatric symptoms caused by thyroid dysfunction.
Methods
Case presentation and non-systematic review of existing literature on Pubmed using the following keywords: hyperthyroidism, psychiatric disorders, psychiatric symptoms, depression, psychosis.
Results
We report the case of a 21-year-old female without history of psychiatric illness who presented to the emergency department with somnolence, apathy, cognitive impairment (answering “I don’t know” to most questions), poverty of speech, abulia, perplexity and delusional belief of ruin, in addition to physical symptoms namely alopecia and weight loss. According to her father, she was very active and dynamic person until two days prior, when he started noticing growing apathy, leading to job absenteeism. Urine analysis for elicit drugs was negative.
Investigation for organic disease was undertaken and the blood analysis revealed overt hyperthyroidism.
She was initially treated with aripiprazol. After thyroid dysfunction was identified, she was evaluated by an endocrinologist and started treatment with tiamazol and propanolol, presenting gradual remission of the psychiatric changes. Aripiprazole was discontinued and she was reevaluated in psychiatry consultation after about a month, with complete remission of psychiatric manifestations and normalized thyroid function.
Conclusions
Neuropsychiatric manifestations of thyroid dysfunction are often misdiagnosed as a primary psychiatric disorder. It is necessary to optimize the medical management of these patients in whom the psychiatric symptoms masks a curable organic cause.
Lithium is one of the main drugs used in Bipolar Affective Disorder. However, it has a narrow therapeutic window, which requires close monitoring and progressive dose adjustment, according to serum levels, clinical response and the appearance of side effects. The term ‘SILENT’ explains descriptively persistent neurological sequelae related to lithium salt intoxication when symptoms persist for more than 2 months after stopping treatment. SILENT Syndrome is more common in females, at ages ranging from 21 to 77 years and is characterized mainly by avermian-type cerebellar disorder, persistent extrapyramidal syndrome, brainstem dysfunction and dementia of varying severity. It can also result in apraxia of the body, changes in the coordination and balance, dysarthria, as well as intentional and kinetic cerebellar tremor, involuntary movements of orofacial dyskinesias or resting tremor.
Objectives
The authors intend to review the relevant and current literature in order to extend the knowledge about this condition and find the best conducts for clinical practice.
Methods
Non-systematic literature review.
Results
Complications from the use of lithium known in the medical literature include mainly nephrotoxicity, endocrine alterations and neurotoxicity. The neurotoxic effects of lithium usually occur at high serum concentrations. However, they can also occur with lithium in the therapeutic range, and memory, attention and ataxia impairment may be some of the permanent sequelae. The etiopathogenesis is unclear, but demyelination has been detected in multiple brain regions, mainly in the cerebellum. The mechanism of lithium-induced cerebellar injury is believed to be mediated by the entry of calcium into the cells of this organ. The main factors that predispose to greater side effects and risk of toxicity are patients with decreased renal function, advanced age, use of diuretics, dementia, pregnancy, low sodium intake and physical illness with vomiting and/or diarrhea.
Conclusions
Lithium is a drug used mostly in affective disorders and given the narrow therapeutic window, it requires close monitoring in order to avoid side effects that can be permanent. In this way, it is important to review the factors that increase the lithium toxicity and make recommendations about it.
The Covid-19 pandemic has generated an unprecedented impact on multiple levels (health, occupational, economic, and social) which affected the general population and has been an enormous stress factor for individuals with obsessive-compulsive disorder (OCD), particularly for those with contamination symptoms. Many patients, as well as healthy individuals, experienced new obsessive-compulsive-like symptoms centered on COVID-19 during the pandemic. However, data on this population are still scarce.
Objectives
To present a case exemplifying the association between the Covid-19 pandemic and the onset of OCD.
Methods
Case presentation and non-systematic review of existing literature on Pubmed using the keywords: Covid-19, OCD, pandemic, depression.
Results
We report a case of a 30-year-old female who presented to the emergency department due to depressive mood and suicidal ideation associated with exacerbation of OCD symptoms, namely intense fear of being infected with Covid-19. These symptoms led to avoidance of touching objects, surfaces or even herself in addition to frequent and long rituals of hand-washing and showers. She was asymptomatic prior to being infected with Covid-19, when she started developing obsessive ideas of contamination. She sought psychiatric support and was medicated with fluoxetine, olanzapine and clonazepam. Due to insufficient symptom control, she was admitted to the psychiatry ward, where treatment was initiated with aripiprazol and fluvoxamine. After dose titration, gradual remission of OCD symptomatology and depressive mood was observed.
Conclusions
The present case illustrates the correlation between Covid-19 and the onset of OCD symptomatology. Existing studies demonstrate that the pandemic worsened the landscape of symptoms of OCD, both in diagnosed patients as well as in previously healthy individuals. However literature is still limited thus, multinational and cross-cultural, longitudinal studies are warranted to gain further insights on this topic.
Epilepsy is one of the most common serious brain illness, with symptoms influenced by multiple risk factors and a strong genetic predisposition, rather than having a single expression and cause¹. Neuropsychiatric symptoms in epilepsy can encompass manifestations such as mood alterations, anxiety, sleep disturbances, psychosis, and behavioral disorders. While the motor and sensory manifestations of epileptic seizures are widely recognized, neuropsychiatric symptoms accompanying epilepsy are often underestimated. Therefore, it is essential to understand the most prevalent epidemiological profile of these patients to improve the diagnosis and management of these symptoms.
Objectives
Our goal was to evaluate the neuropsychiatric behavior of epilepsy patients in Brazilian over the past 3 years through hospitalization data in order to outline an epidemiological and behavioral profile.
Methods
A cross-sectional, descriptive, retrospective, and quantitative study was conducted on hospitalizations of individuals simultaneously diagnosed with epilepsy, schizotypal and delusional disorders, and mood disorders in all five regions of Brazil (South, Southeast, Midwest, North, and Northeast) between February 2020 and December 2022. Data from January 2020 were not available. The data used were collected through the Department of Health Informatics of the Brazilian Unified Health System (DATASUS) in the “Hospital Information System of SUS” section, gathering information regarding the nature of care, age range, gender, and ethnicity of the patients.
Results
The analysis covers the years 2020 to 2022, totaling 503,045 hospitalizations. In 2022, the highest number of cases occurred (≈ 37.55%), followed by 2021 (≈ 33.62%) and 2020 (≈ 28.81%). Urgent hospitalizations represented ≈ 90.85% of the total. The most affected age group was 30 to 39 years old (≈ 18.30%). Men were more affected than women (≈ 52.03% and ≈ 47.96%, respectively), and Caucasians accounted for ≈ 36.07% of the hospitalizations. The average length of stay was 19.1 days, and the mortality rate was 1.4%.
Conclusions
Thus, there is a gradual and annual increase in the number of hospitalizations during the observed period. While there is a minimal disparity between the affected genders, it is evident that the profile of male, caucasian, and adult patients is the most prevalent. Moreover, the predominantly urgent nature of hospitalizations points to an alarming scenario regarding this issue. From the analysis of the data obtained in the study, there is a clear need for interventions capable of reducing the prevalence of hospitalizations for neuropsychiatric symptoms in epilepsy patients in Brazil.
Neuropsychiatric disorders are the leading cause of disability worldwide, as seen in cases such as depression, anxiety, bipolar mood disorder and schizophrenia, which can be developed or exacerbated by the use of psychoactive substances. Most mental disorders have an early onset, often leading to early and/or permanent disability, increasing the need and cost of healthcare. Therefore, it is necessary to improve the identification of the epidemiological profile of these cases in the South of Brazil in order to enhance the diagnosis and reduce the costs associated with managing these disorders.
Objectives
The present study aimed to analyze statistical data regarding hospitalizations related to mental disorders caused by the use of psychoactive substances and alcohol in the southern region of Brazil, highlighting the pathological scenario and identifying the most prevalent profiles of these disorders in this region.
Methods
A cross-sectional, descriptive, retrospective, and quantitative study was conducted on hospitalizations of individuals diagnosed with mental and behavioral disorders due to the use of psychoactive substances and alcohol in the states of the Southern region of Brazil (Paraná, Santa Catarina, and Rio Grande do Sul) between February 2020 and December 2022. Data of January 2020 were not available. The data used were collected through the Department of Health Informatics of the Brazilian Unified Health System (DATASUS) in the “Hospital Information System of SUS” section, gathering information regarding the nature of the care, age range, gender, and ethnicity of the patients.
Results
The study covers the years 2020 to 2022, indicating a total of 81,608 hospitalizations, with the year 2022 having the highest number of cases (≈ 37.13%), followed by 2021 (≈ 33.30%) and 2020 (≈ 29.55%). The states with the highest number of hospitalizations were Rio Grande do Sul (≈ 54.90%), Paraná (≈ 29.29%), and Santa Catarina (≈ 15.79%). Urgent hospitalizations accounted for ≈ 87.29% of the total. The most affected age group was 30 to 39 years old (≈ 25.61%). Men were more affected than women (≈ 81.70% and ≈ 18.28%, respectively). Caucasians accounted for ≈ 64.29% of the hospitalizations. The average length of stay was 20.8 days, and the mortality rate was 0.32%.
Conclusions
There is a clear increase in the number of hospitalizations related to mental disorders caused by the use of psychoactive substances in the period from 2020 to 2022 in the southern region of Brazil, with the highest number of cases in the state of Rio Grande do Sul. The most affected population consisted of Caucasian men aged 30 to 39 years old. Furthermore, these results may be related to the increasing trend of psychoactive substance use among the Brazilian population and also the COVID-19 pandemic, which led to a period of underreporting due to social isolation.
Sodium oxybate, an effective treatment for narcolepsy-associated daytime sleepiness and cataplexy, has been extensively. Despite its therapeutic benefits, sodium oxybate is not without its risks, and adverse psychiatric effects have been documented. This case report highlights a rare manifestation of sodium oxybate-related secondary mania with psychotic symptoms in a patient with narcolepsy, emphasizing the importance of recognizing and managing such adverse events. Additionally, we provide a brief review of similar cases reported in the literature.
Objectives
This report aims to describe the presentation, evaluation, and management of sodium oxybate-induced secondary mania with psychotic symptoms in a patient with narcolepsy. We also discuss the potential mechanisms underlying this adverse reaction and its clinical implications. Furthermore, we summarize findings from previous studies that have reported cases of secondary mania associated with sodium oxybate use.
Methods
We present the case of Mr. X, a 48-year-old male diagnosed with “Narcolepsy with cataplexy,” who had been receiving sodium oxybate treatment for 11 years. He was admitted to the hospital following a mild head injury and the emergence of a manic episode with psychotic features. Comprehensive clinical evaluation, including medical history, toxicology screening, and neuroimaging, was conducted.
Results
Upon evaluation, Mr. X exhibited hyperactivity, restlessnes, grandiose delusions, paranoid delusions related to hospital staff, and decreased need for sleep. Notably, he had been consuming sodium oxybate excessively. Sodium oxybate was discontinued, and low-dose olanzapine was initiated. Within 24 hours, his manic and psychotic symptoms resolved. He admitted to overusing his medication, and his family reported a recent increase in his activity level. A review of the literature revealed similar cases of sodium oxybate-induced secondary mania with psychotic symptoms.
Conclusions
This case underscores the importance of vigilance for psychiatric side effects of sodium oxybate, particularly in patients with a history of substance abuse or potential overuse. Secondary mania associated with medications is a rare but significant clinical entity. Prompt recognition and intervention are crucial for patient safety and well-being. Further research is needed to elucidate the mechanisms underlying such reactions and to establish guidelines for their prevention and management.
In recent years, mental health has gained prominence in public health, prompting thorough investigations into psychiatric condition trends. This study conducts a comprehensive epidemiological analysis of hospitalizations for Schizophrenia, Schizotypal, and Delirium Disorders in Rio Grande do Sul (RS) over the past five years. By revealing these patterns, it enhances our understanding of regional mental health dynamics and offers insights for intervention strategies, resource planning, and improved mental healthcare. The ultimate goal is to advance more effective and accessible mental healthcare in RS and beyond.
Objectives
This study aims to analyze the prevalence and epidemiological profile of hospitalizations due to psychiatric disorders to assist in the diagnosis and outcome of affected patients.
Methods
A cross-sectional, descriptive, retrospective, and quantitative study was conducted regarding hospitalizations for Schizophrenia, Schizotypal Disorders, and Delirium in the state of RS between January 2018 and November 2022. Data were collected from the Department of Informatics of the Brazilian Unified Health System (DATASUS) in the “Hospital Information System of SUS” section, focusing on the nature of care, age group, gender, and ethnicity of the patients. The information was aggregated over the five-year period based on the four mentioned descriptors and subsequently analyzed to establish a profile of hospitalizations during that period.
Results
The analysis spans from 2018 to 2022, encompassing a total of 28,345 hospitalizations. In 2019, there was the highest number of cases (22.21%), followed by 2018 (21.08%). Urgent care admissions constituted 85.34% of the total. The age group most affected was 35 to 39 years (11.8%). Men were more affected than women (60.18%), and the majority of hospitalizations were among the Caucasian ethnicity (75.12%). The average length of stay was 23.7 days, and the mortality rate stood at 0.26%.
Conclusions
The increasing trend in hospitalizations, peaking in 2019, highlights the need for preventive measures. Urgent admissions (85.34%) underscore the demand for accessible mental health resources. Men in the 35 to 39 age group are disproportionately affected, suggesting specific risk factors. The predominance of Caucasian ethnicity emphasizes the need for culturally sensitive care. A longer average length of stay (23.7 days) underscores treatment complexity, while a low mortality rate (0.26%) signals effective medical care. In essence, these findings inform tailored mental health policies to enhance service quality and prioritize patient-centered approaches.
The United States of America are currently facing a public health crisis characterized by the abuse of synthetic opioids, notably Fentanyl, and the veterinary sedative Xylazine. While each of these substances has been associated with significant risks, their current misuse presents a formidable challenge to healthcare professionals, law enforcement agencies and policymakers. While the opioid epidemic has long held the nation in its grip, the emergence of Xylazine as complementary agent in substance abuse has added a disturbing layer of complexity to an already terrible situation, due to its cost-cutting, an increase in its addictive properties and its ability to extend the duration of the opioid with which it is combined.
Objectives
The authors intend to review the relevant and current literature in order to extend the knowledge about this condition and find the best conducts for clinical practice.
Methods
Non-systematic literature review
Results
Various regions of the United States are facing a troubling surge in the co-abuse of Fentanyl, a potent synthetic opioid many times more potent than morphine, and Xylazine, a veterinary sedative and muscle relaxant, particularly in urban areas. The motivations for this combination appear to vary, ranging from the enhanced euphoria to cost-saving measures, further fueling its prevalence. However, the consequences are devastating. Both substances depress the central nervous system, with a sharp increase in overdose deaths and emergency medical services are strained to their limits in responding to these crises. Law enforcement agencies are facing a daunting task in curtailing the distribution of these substances, often grappling with clandestine networks that exploit the accessibility of these drugs.
Conclusions
The concurrent abuse of Fentanyl and Xylazine represents a critical public health challenge in the United States of America, demanding immediate attention and a multidisciplinary response. Failure to address this issue comprehensively will have profound implications for the well-being of individuals, families and communities across the nation. It is imperative to mobilize resources, foster interdisciplinary collaboration and develop evidence-based policies to combat this dual-threat crisis. Novel intervention strategies, including community education programs, targeted outreach efforts, and supervised consumption facilities, are urgently needed to address this complex issue.
Artificial stacking faults can be created within a well-crystallized kaolinite by intercalating and removing hydrazine. X-ray powder patterns with electron microscopy show that the created defects are ±b/3 translations with a proportion 0.30. The infrared spectrum of the treated kaolinite is not modified with respect to the starting one. On the other hand, a natural kaolinite containing defects by displacement of Al vacancies in a similar proportion shows an infrared spectrum significantly different from that of a well-crystallized kaolinite. The modification of the infrared spectra of natural disordered kaolinites is then related to the presence of defects by change of Al vacancy positions
The adsorption of CO2 at low temperature (~ -70°C) on thin films of homoionic smectites was studied by X-ray diffraction and by i.r. absorption. An increase in the d001 spacings of these clay films upon adsorption of CO2 was observed. In addition, a dichroic effect was readily discernible by comparing the i.r. spectra at two different orientations of the smectite films; i.e. with the film normal and tilted 35° with respect to the i.r. beam. The CO2 stretching vibration at 2350 cm-1 was used for the i.r. study. These observations conclusively show that CO2 intercalates the smectite structure rather than being adsorbed only in pores between clay tactoids—the limiting process proposed by other investigators.
Adsorption isotherm data from earlier surface area studies are re-examined here through application of the Dubinin equation. Again, intercalation is demonstrated by convergence of the plotted experimental data for smectites containing large monovalent interlayer cations toward a pore volume that is near the calculated theoretical value for a monolayer of intercalated CO2.
Scanning electron photomicrographs of Li- and Cs- smectites provide additional evidence that aggregation differences are not responsible for the large observed difference in BET surface areas obtained for these smectites with CO2 as the adsorbate. At low magnification, visual differences in macro-aggregates are apparent, but at high magnification no significant differences are observed in the micro-structure of individual aggregates where the major amount of gas adsorption really occurs.
The adsorption of the cationic oxidized safranine S+ by a Na+, Ni2+ and Fe3+ montmorillonite has been studied with X-ray powder diffraction, u.v., visible and i.r. spectroscopy. In solution S+ may be protonated: S+, SH2+ and SH23+ have characteristic spectra in the 500–600 nm region where the clay structure does not absorb. In the Na+ as well as in the Ni2+ and Fe3+ clays, the adsorption of S+ is a cation exchange process accompanied by the protonation of the adsorbed dye such as variable concentrations of M+ (Na+, Ni2+ or Fe3+), S+ and SH2+ are simultaneously present. Protonation activity decreases from Fe3+ to Ni2+ and Na+, being the protonation site the amine group as shown by i.r. In the interlamellar space it seems that a SH2+.. S+ association exists that could be described as a sandwich structure 6.5 Å thick.
Adsorption isotherms of HCN by Cu- and Ca-montmorillonites show that water present in the interlayer space decreases HCN adsorption.
For Ca-montmorillonite, i.r. spectra permit distinguishing between HCN interacting with the cations and molecules filling the interlayer space. Both types are removed upon outgassing. The residual water is not displaced by HCN.
On Cu-montmorillonite, species (presumably CN− ions) strongly held by the cations are observed in addition to adsorbed HCN molecules. The residual hydroxyls retained in the interlayer space are removed by the adsorption of HCN. These hydroxyls, either OH− or H2O, are characterized by two well defined stretching bands.
Infra-red spectra of samples heated below 200°C show that adsorbed HCN is involved in chemical reactions. For both clays, bands appear in the region characteristic of carbonyl and carboxyl groups; the production of ammonium is detected for Cu-montmorillonite. The reactions and the observed spectral features could be accounted for by the formation of formamide.
The adsorption of Sn(IV)TPyP (mesotetrapyridylporphyrin) in sodium hectorite was studied using ultraviolet-visible and luminescence spectroscopy. The adsorbed complex was found to demetallate forming the TPyP dication as the clay is dehydrated. This process was found to be reversible indicating that the Sn4+ ion remains in the vicinity of the porphyrin upon demetallation. The luminescence spectrum of the adsorbed complex was found to be a composite of the Sn(IV)TPyP and the dication spectra. The presence of a band at 750 nm in the luminescence spectrum of the adsorbed species suggested an enhanced interaction between the π-systems of the pyridyl substituents and the porphin nucleus. This is believed to result from a decrease in the dihedral angle between the nucleus and the substituents when they are squeezed between the clay sheets.
Members of the genus Scaphanocephalus mature in accipitrids, particularly osprey, Pandion haliaetus, with metacercaria causing Black Spot Syndrome in reef fishes. In most of the world, only the type species, Scaphanocephalus expansus (Creplin, 1842) has been reported. Recent molecular studies in the Western Atlantic, Mediterranean and Persian Gulf reveal multiple species of Scaphanocephalus, but have relied on 28S rDNA, mainly from metacercariae, which limits both morphological identification and resolution of closely related species. Here we combine nuclear rDNA with mitochondrial sequences from adult worms collected in osprey across North America and the Caribbean to describe species and elucidate life cycles in Scaphanocephalus. A new species described herein can be distinguished from S. expansus based on overall body shape and size. Phylogenetic analysis of the whole mitochondrial genome of Scaphanocephalus indicates a close relationship with Cryptocotyle. We conclude that at least 3 species of Scaphanocephalus are present in the Americas and 2 others are in the Old World. Specimens in the Americas have similar or identical 28S to those in the Mediterranean and Persian Gulf, but amphi-Atlantic species are unlikely in light of divergence in cytochrome c oxidase I and the lack of amphi-Atlantic avian and fish hosts. Our results provide insight into the geographic distribution and taxonomy of a little-studied trematode recently linked to an emerging pathology in ecologically important reef fishes.