The connection between Submarine Groundwater Discharge and seawater quality: The threat of treated wastewater injected into coastal aquifers

Submarine Groundwater Discharge (SGD) delivers nutrients to the coastal sea triggering phytoplankton blooms, eutrophication, and can also serve as a pathway for contaminants. Wastewater treatment plants (WWTP) including injection wells in coastal areas influence coastal aquifers and might impact the composition and magnitude of SGD fluxes. In tourist areas, wastewater treatment may be less efficient and larger in volume during high seasons, potentially impacting nutrient fluxes from SGD and exacerbating environmental impacts. This study analyzes the nutrient transfer from treated wastewater injection in karstic aquifers to the coastal sea via SGD, considering the impacts of tourism seasonality. This study is conducted in Cala Deià, a small cove in the Balearic Islands, a Mediterranean tourist destination. The findings suggest that the seasonality of tourism, leading to variations in the volume of wastewater treated in the WWTP, influences the dynamics of the coastal aquifer. This leads to increased SGD water and nutrient fluxes to the sea in summer, i.e. the peak tourist season. The measured DIN, DIP, and DSi inventories in the cove are much larger in August than in April (3, 10, and 1.5 times higher, respectively) due to higher input of nutrients in summer due to SGD impacted by the WWTP. These elevated nutrient flows can support algal blooms in the cove, compromising water quality for local swimmers and tourists. Indeed, in August, shoreline stations exhibited eutrophic Chl-a concentrations, with peaks reaching approximately 4 mg Chl-a L-1. These elevated levels suggest the presence of an algal bloom during the survey. The anthropogenic origin of SGD-driven nutrients is traced in seawater and seagrass meadows, as evidenced by high ∂15N signatures indicative of polluted areas. Thus, the high pressure exerted on coastal areas by tourism activities increased the magnitude of SGD nutrient fluxes, thereby threatening coastal ecosystems and the services they provide.

Evaluating the extent and impact of the extreme Storm Gloria on Posidonia oceanica seagrass meadows

Extreme storms can trigger abrupt and often lasting changes in ecosystems by affecting foundational (habitat-forming) species. While the frequency and intensity of extreme events are projected to increase under climate change, its impacts on seagrass ecosystems remain poorly documented. In January 2020, the Spanish Mediterranean coast was hit by Storm Gloria, one of the most devastating recent climate events in terms of intensity and duration. We conducted rapid surveys of 42 Posidonia oceanica meadows across the region to evaluate the extent and type of impact (burial, unburial and uprooting). We investigated the significance of oceanographic (wave impact model), geomorphological (latitude, depth, exposure), and structural (patchiness) factors in predicting impact extent and intensity. The predominant impact of Storm Gloria was shoot unburial. More than half of the surveyed sites revealed recent unburial, with up to 40 cm of sediment removed, affecting over 50 % of the meadow. Burial, although less extensive, was still significant, with 10-80 % of meadow cover being buried under 7 cm of sediment, which is considered a survival threshold for P. oceanica. In addition, we observed evident signs of recently dead matte in some meadows and large amounts of detached drifting shoots on the sea bottom or accumulated as debris on the beaches. Crucially, exposed and patchy meadows were much more vulnerable to the overall impact than sheltered or continuous meadows. Given how slow P. oceanica is able to recover after disturbances, we state that it could take from decades to centuries for it to recoup its losses. Seagrass ecosystems play a vital role as coastal ecological infrastructure. Protecting vulnerable meadows from anthropogenic fragmentation is crucial for ensuring the resilience of these ecosystems in the face of the climate crisis.

Metastatic pulmonary dissemination as differential diagnosis of COVID-19 disease

A 13-year-old boy presented to hospital with 3-day self-limited fever, followed by dry cough, persistent asthenia and impaired general condition of 2 weeks' duration. Blood analyses showed a severe inflammatory status and chest X-ray images were consistent with bilateral COVID-19 pneumonia. He developed an acute respiratory failure that required paediatric intensive care admission and non-invasive ventilation. A targeted COVID-19 treatment was initiated with hydroxicloroquine, corticosteroids, enoxaparine and a single dose of tocilizumab. Repeated serological tests and real-time reverse transcription PCR for SARS-CoV-2 were negative. Other infectious pathogens were also ruled out. Thoracic high resolution CT showed an intense bilateral pulmonary dissemination with lytic vertebral bone lesions. After diagnostic investigations, Ewing's sarcoma with metastatic pulmonary dissemination was diagnosed. Nowadays, in the context of SARS-CoV-2 community pandemic, we cannot forget that COVID-19 clinical presentation is not specific and other entities can mimic its clinical features.

Scalable Large-Margin Distance Metric Learning Using Stochastic Gradient Descent

The key to success of many machine learning and pattern recognition algorithms is the way of computing distances between the input data. In this paper, we propose a large-margin-based approach, called the large-margin distance metric learning (LMDML), for learning a Mahalanobis distance metric. LMDML employs the principle of margin maximization to learn the distance metric with the goal of improving k -nearest-neighbor classification. The main challenge of distance metric learning is the positive semidefiniteness constraint on the Mahalanobis matrix. Semidefinite programming is commonly used to enforce this constraint, but it becomes computationally intractable on large-scale data sets. To overcome this limitation, we develop an efficient algorithm based on a stochastic gradient descent. Our algorithm can avoid the computations of the full gradient and ensure that the learned matrix remains within the positive semidefinite cone after each iteration. Extensive experiments show that the proposed algorithm is scalable to large data sets and outperforms other state-of-the-art distance metric learning approaches regarding classification accuracy and training time.

Understanding Chemical Selectivity through Well Selected Excited States

In this publication, we propose a new set of reactivity/selectivity descriptors, derived within a Rayleigh-Schrödinger perturbation theory framework, for chemical systems undergoing an electrostatic (point-charge) perturbation. From the electron density polarization at first order, qualitative insight on reactivity is retrieved, while more quantitative information (noteworthy selectivity) can be obtained from either the second-order energy response or the number of shifted electrons under perturbation. Noteworthily, only a small number of excitations contribute significantly to the overall responses to perturbation, suggesting chemical reactivity could be foreseen by a careful scrutiny of the electron density reorganization upon excitation.

Comment on “Revisiting the definition of local hardness and hardness kernel” by C. A. Polanco-Ramirez, M. Franco-Pérez, J. Carmona-Espíndola, J. L. Gázquez and P. W. Ayers, Phys. Chem. Chem. Phys., 2017, 19, 12355

In this comment we show that the derivation proposed Polanco-Ramirez et al. appears naturally in the Taylor expansion of the energy, showing that their whole construction is not artificially built.

Intravenous isotonic fluids induced a positive trend in natraemia in children admitted to a general paediatric ward

AIM

Using hypotonic intravenous solutions for baseline fluid needs in paediatric patients on a nil by mouth diet may cause serious complications, including hyponatraemia, cerebral oedema and even death. We analysed the evolution of natraemia and explored any adverse effects on children treated with intravenous isotonic fluids.

METHODS

This was a prospective study of 50 patients consecutively admitted to a general paediatric ward who were treated with isotonic intravenous fluids and on a nil by mouth diet.

RESULTS

The most prevalent diagnosis was acute gastroenteritis (64%). Hyponatraemia, defined as sodium in plasma of <135 mEq/L, affected 22% of the subjects, but none displayed this during the first postadmission analysis at a median of eight hours. Sodium levels changed by an average of +0.64 mEq/L/hour. The subgroup analysis (0.91 versus 0.56 mEq/L/hour, p = 0.02) and multiple linear regression (R(2) = 0.756) showed a greater increase in sodium when patients had hyponatraemia on admission. Iatrogenic hyponatraemia was not detected, but two patients showed mild hypernatraemia and 35% developed clinically insignificant hyperchloraemia.

CONCLUSION

Using intravenous isotonic fluids induced a positive trend in natraemia on a general paediatric ward, particularly if patients were hyponatraemic when admitted, and did not induce clinically relevant adverse effects.

Differences in prevalence of inflammatory bowel disease in Puerto Rico between commercial and government-sponsored managed health care insured individuals

BACKGROUND

Evaluation of ethnic and racial patterns of Inflammatory Bowel Disease (IBD) has demonstrated a higher incidence of IBD in Jews, and lower rates in blacks and Hispanics when compared to whites. There is limited data describing incidence and prevalence among Hispanics, the fastest growing minority in the United States.

METHODS

To estimate the prevalence of IBD computerized records of all physicians billing and hospital discharges classified with ICD-9-CM IBD related codes were searched. Prevalence was estimated by age group, sex, and type of insurance (commercial versus government-sponsored managed care).

RESULTS

Of 1,248,993 insured individuals in 2005, 186 had a diagnosis of Crohn's disease and 291 of ulcerative colitis. The estimated prevalence per 100,000 was 14.9 for Crohn's disease, 23.3 for ulcerative colitis, and 38.2 cases for IBD. The most significant difference was found when comparing insurance type, with a total IBD prevalence rate of 61.75 cases among commercial versus 14.36 cases among government-sponsored insured.

CONCLUSIONS

The prevalence of IBD in this insured population in Puerto Rico places it among the highest described in a Hispanic population. Given the continued rise in prevalence of IBD and the limited studies describing the epidemiology of IBD in Hispanics, further studies which may provide important clues to the etiology of the disease as well as valuable information for appropriate health care planning are important.

Desirability-based methods of multiobjective optimization and ranking for global QSAR studies. Filtering safe and potent drug candidates from combinatorial libraries

Up to now, very few applications of multiobjective optimization (MOOP) techniques to quantitative structure-activity relationship (QSAR) studies have been reported in the literature. However, none of them report the optimization of objectives related directly to the final pharmaceutical profile of a drug. In this paper, a MOOP method based on Derringer's desirability function that allows conducting global QSAR studies, simultaneously considering the potency, bioavailability, and safety of a set of drug candidates, is introduced. The results of the desirability-based MOOP (the levels of the predictor variables concurrently producing the best possible compromise between the properties determining an optimal drug candidate) are used for the implementation of a ranking method that is also based on the application of desirability functions. This method allows ranking drug candidates with unknown pharmaceutical properties from combinatorial libraries according to the degree of similarity with the previously determined optimal candidate. Application of this method will make it possible to filter the most promising drug candidates of a library (the best-ranked candidates), which should have the best pharmaceutical profile (the best compromise between potency, safety and bioavailability). In addition, a validation method of the ranking process, as well as a quantitative measure of the quality of a ranking, the ranking quality index (Psi), is proposed. The usefulness of the desirability-based methods of MOOP and ranking is demonstrated by its application to a library of 95 fluoroquinolones, reporting their gram-negative antibacterial activity and mammalian cell cytotoxicity. Finally, the combined use of the desirability-based methods of MOOP and ranking proposed here seems to be a valuable tool for rational drug discovery and development.

*H atom and *OH radical reactions with 5-methylcytosine

The reactions between either a hydrogen atom or a hydroxyl radical and 5-methylcytosine (5-MeCyt) are studied by using the hybrid kinetic energy meta-GGA functional MPW1B95. *H atom and *OH radical addition to positions C5 and C6 of 5-MeCyt, or *OH radical induced H-abstraction from the C5 methyl group, are explored. All systems are optimized in bulk solvent. The data presented show that the barriers to reaction are very low: ca. 7 kcal/mol for the *H atom additions and 1 kcal/mol for the reactions involving the *OH radical. Thermodynamically, the two C6 radical adducts and the *H-abstraction product are the most stable ones. The proton hyperfine coupling constants (HFCC), computed at the IEFPCM/MPW1B95/6-311++G(2d,2p) level, agree well with B3LYP results and available experimental and theoretical data on related thymine and cytosine radicals.

Prevalence of inflammatory bowel disease in an insured population in Puerto Rico during 1996

OBJECTIVES

Limited data exists about Inflammatory Bowel Disease (IBD) in Hispanic populations. The aims of the present study were to estimate overall and specific prevalence of IBD (Crohn's disease and ulcerative colitis) and to describe the characteristics of a group of patients from the University of Puerto Rico's IBD Registry.

METHODS

To estimate the prevalence of IBD, computerized records of all physician billing and hospital discharges from a major health insurer in Puerto Rico and classified with ICD-9-CM codes 555.0-555.9 (Crohn's disease) and 556.0-556.9 (ulcerative colitis) during 1996 were searched. Prevalence was estimated by age group, sex, and type of insurance. To describe demographic and selected clinical information from patients with IBD, data gathered in the University of Puerto Rico's IBD Registry from 1995 through 2000 was analyzed.

RESULTS

Out of 802,726 insured individuals, 332 had a diagnosis of Crohn's disease, 499 of ulcerative colitis and 21 had both diagnoses. The estimated prevalence per 100,000 was 41.4 for Crohn's disease, 62.2 for ulcerative colitis, and 106.1 cases per 100,000 for IBD. Peak prevalence of Crohn's disease occurred among the age groups 50-59 years and > or = 60 years, and the overall female:male prevalence ratio of Crohn's disease was 1.13 (95% CI: 0.91-1.42). Ulcerative colitis was most prevalent among insured individuals aged 50-59 years and 40-49 years. The prevalence of ulcerative colitis was significantly higher among females than among males, with an overall prevalence ratio of 1.42 (95% CI: 1.18-1.71). Of 342 patients participating in the IBD Registry, 155 (45.3%) had Crohn's disease and 187 (54.7%) had ulcerative colitis. Among patients diagnosed with Crohn's disease, 51.6% were females, the mean age was 35.2 +/- 18.3 years, and 18.1% had a family history of IBD. More than half (57.8%) of patients with ulcerative colitis were females, the mean age was 42.6 +/- 17 years, and 17.1% had a family history of IBD.

CONCLUSIONS

The estimated prevalence of IBD in this insured population in Puerto Rico places it among the middle-range of that reported for other countries. Additional studies must be conducted in Puerto Rico in order to confirm the observed findings. Population-based epidemiologic studies aimed at estimating the burden of IBD in Hispanic populations in the United States and Latin America are essential for health care planning.

[The prevalence of asthma and the utilization of medical services among those insured by a health-services company in Puerto Rico, 1996-1997]

OBJECTIVE

To describe the prevalence and pattern of utilization of medical services in insured of SSS with a diagnosis of asthma during 1996 and 1997.

METHODS

The medical claims of SSS insured whose main diagnosis was asthma (ICD-9 9 493-493.9) were selected for analysis. The prevalence and medical service utilization (medical visits, emergency and hospital admissions) were estimated. Differences in health service utilization by age group were analyzed by the Poisson model.

RESULTS

The asthma prevalence was 14.5%, being larger in patients younger than 18 years of age and in females. 54.3% of the asthmatic patients visited medical offices and the larger proportion of users was observed in the younger group (< 18 years). However, the larger proportion of users of the emergency room was observed in the 18-44 age group, while the hospital admissions was larger in the 45-64 age group. More than half (56%) of the cost per service was attributed to hospital admissions while 31% was for pharmacy services. 65.9% of the insurers with asthma had prescriptions for short relief beta-antagonist.

CONCLUSIONS

The prevalence of asthma in this study was high and similar to rates of the disease reported in Puerto Ricans residing in the U. S. and in other areas of the island. Similarly, the prevalence differed by age in the utilization of medical services as well as the high cost of hospital admissions. Prevalence studies using other sources as well as a standard definition of the condition may be helpful to confirm these results.

Radicalizing recovery: addiction, spirituality, and politics

Treatment centers and self-help recovery programs promote individual solutions to substance abuse through changing dysfunctional behavior and relying on spiritual beliefs and practices. The root problems are understood to be diseases within the person. However, the social conditions implicated in causing the addiction remain unaddressed. Although class, race, and gender do not predict substance abuse, many people entering clinics are from disempowered groups. Can social workers bring recovery and social justice methods together? What can radical social workers in the addiction-recovery industry do?