Harvesting freshwater algae with tannins from the bark of forest species: Comparison of methods and pelletization of the biomass obtained

Toxic cyanobacteria growth rates have increased in recent decades due to climate change and human activities. Microalgae, with their ability to produce a large amount of biomass, are considered as a source of energy that can be used to produce biofuels. The aim of this study is to test four different microalgae harvesting methods (sedimentation, coagulation-flocculation, pH variation, and centrifugation) in order to find which is best suited to the A Baxe reservoir, which has been suffering from cyanobacterial blooms in recent years. Centrifugation proved the most efficient method (85.74%-1790 RCF), but it can induce cell rupture. Natural sedimentation and pH variation obtained similar results at 49.36% and 49.02% respectively. Although all four methods have advantages, our results reveal that coagulation-flocculation, using 10 mg/L of Pinus pinaster, results in a removal efficiency of 68.10%, making it the most suitable method, though with 20 mg/L the performance was lower (66.03%). To minimise environmental waste, the microalgae removed were then transformed into pellets to be used as biofuel, with a higher heating value (HHV) of 21,196.96 ± 1602.33 kJ/kg. The pellets obtained from the microalgae residue did not meet all the requirements for use as biofuels, but microalgae biomass could be mixed with other sources and therefore looks like a promising option for the future.

Computer Vision Applied to Detect Lethargy through Animal Motion Monitoring: A Trial on African Swine Fever in Wild Boar

Early detection of infectious diseases is the most cost-effective strategy in disease surveillance for reducing the risk of outbreaks. Latest deep learning and computer vision improvements are powerful tools that potentially open up a new field of research in epidemiology and disease control. These techniques were used here to develop an algorithm aimed to track and compute animal motion in real time. This algorithm was used in experimental trials in order to assess African swine fever (ASF) infection course in Eurasian wild boar. Overall, the outcomes showed negative correlation between motion reduction and fever caused by ASF infection. In addition, infected animals computed significant lower movements compared to uninfected animals. The obtained results suggest that a motion monitoring system based on artificial vision may be used in indoors to trigger suspicions of fever. It would help farmers and animal health services to detect early clinical signs compatible with infectious diseases. This technology shows a promising non-intrusive, economic and real time solution in the livestock industry with especial interest in ASF, considering the current concern in the world pig industry.

Winter movement patterns of a globally endangered avian scavenger in south-western Europe

Partial migration, whereby some individuals migrate and some do not, is relatively common and widespread among animals. Switching between migration tactics (from migratory to resident or vice versa) occurs at individual and population levels. Here, we describe for the first time the movement ecology of the largest wintering population of Egyptian Vultures (Neophron percnopterus) in south-west Europe. We combined field surveys and GPS tracking data from December to February during four wintering seasons (2014–2018). The wintering population consisted on average of 85 individuals (range 58–121; 76% adults and 24% subadults). Individuals were counted at five different roosting sites located near farms, unauthorized carcass deposition sites and authorized carcass deposition sites. Our results show that vultures tend to remain close to the roosting site. Moreover, we observed that females exhibited smaller home range sizes than males, which suggests a possible differential use of food sources. Overall, birds relied more on farms than other available food resources, particularly subadult individuals which exploited more intensively these sites. Our results showed that Egyptian Vultures congregate in significant numbers at specific sites throughout the winter period in south-west Spain and that these roosting and feeding sites should be given some level of legal protection and regular monitoring. Furthermore, predictable food sources might be driving the apparent increase in the non-migratory population of Egyptian Vultures, as observed in other avian species which are also changing their migratory behavior.

[COVID-19 Pandemic: Impact and rapid reaction of Urology]

The COVID-19 pandemic caused by the SARS-CoV-2 virus has caused tens of thousands of deaths in Spain and has managed to breakdown the healthcare system hospitals in the Community of Madrid, largely due to its tendency to cause severe pneumonia, requiring ventilatory support. This fact has caused our center to collapse, with 130% of its beds occupied by COVID-19 patients, thus causing the absolute cessation of activity of the urology service, the practical disappearance of resident training programs, and the incorporation of a good part of the urology staff into the group of medical personnel attending these patients. In order to recover from this extraordinary level of suspended activity, we will be obliged to prioritize pathologies based on purely clinical criteria, for which tables including the relevance of each pathology within each area of urology are being proposed. Technology tools such as online training courses or surgical simulators may be convenient for the necessary reestablishment of resident education.

Assessment of water quality in eutrophized water bodies through the application of indexes and toxicity

It is essential to have tools that can be used to diagnose water resources. For this reason, this study sets out on the one hand to assess water quality in three reservoirs in Spain (Salas, A Baxe and Conchas) with Cyano-Habs problems through the application of water quality indexes: The National Sanitation Foundation Water Quality Index (NFSWQI), the General Quality Index (GQI), the Trophic State Index (TSI), and the Trophic Contamination Index (ICOTRO). On the other hand, it seeks to learn how parameters such as nitrogen and phosphorus influence the presence of cyanotoxin, specifically Microcystis aeruginosa. To that end, samples from the three reservoirs are cultured and physical-chemical parameters and the toxicity of the water are measured. The results show that Salas reservoir has the worst water quality rating (GQI is bad and NFSWQI medium), while As Conchas and A Baxe obtain very good figures for NFSWQI. This contrasts with the data obtained via the TSI of moderately eutrophic conditions for all three reservoirs, and hypereutrophic levels for As Conchas and A Baxe downstream. On the other hand, the toxicity analysis shows levels of 1.12 ± 0.06 μg/l microcystin-LR (MC-LR) for As Conchas, 0.64 ± 0.04 μg/l MC-LR for Salas, and 1.24 ± 0.05 μg/l MC-LR for A Baxe, of which 20% corresponds to free MC-LR. This study finds that nitrogen is the parameter that most favors the production of MC-LR. We conclude that the eutrophication indexes are more reliable when studying the presence of cyanobacteria. Furthermore, nitrogen and phosphorous are the most significant parameters in this regard. They are taken into account in the quality indices (GQI, NFSWI), but they are not sufficiently representative. It is recommended as a future line of research that water quality indices be adapted or designed to incorporate eutrophication levels and even water toxicity.

Influence of Microcystis sp. and freshwater algae on pH: Changes in their growth associated with sediment

Samples from two reservoirs with eutrophication problems, located in Pontevedra and Ourense (Northwestern Spain), were cultured, along with a third crop from a reservoir with no problems detected in Ourense (Northwestern Spain). The samples were grown under the same conditions (with an average temperature of 21 ± 2 °C, and a 3000 lux light intensity) in triplicate, and their growth, absorbance and pH were studied. High correlation values were obtained for pH and cellular growth (R² ≥ 95%). The water from Salas showed the greatest microalgal growth (0.15 × 10⁶ cells/ml to 31.70 × 10⁶ cells/ml of Microcystis sp. for the last day of culturing) and the greatest increase in pH (5.72-9.02). In all the cultures studied here, the main species that reproduced was Microcystis sp., which can produce neurotoxins and hepatotoxins. In addition, water samples were cultured with sediments of their own reservoir and with others to observe their evolution. The sediments studied in this case were rich in biotites, which can lead phosphate to be a limiting factor for phytoplankton due to the formation and sedimentation of insoluble salts of ferric phosphate. In crops grown with sediments from the Salas reservoir, actinobacteria developed which can inhibit microalgal growth. The study of the growth of cyanobacteria and possible methods of inhibiting them directly concerns the quality of water and its ecosystems, avoiding pollution and impact on ecosystems.

Effect of network topology and node centrality on trading

Global supply networks in agriculture, manufacturing, and services are a defining feature of the modern world. The efficiency and the distribution of surpluses across different parts of these networks depend on the choices of intermediaries. This paper conducts price formation experiments with human subjects located in large complex networks to develop a better understanding of the principles governing behavior. Our first experimental finding is that prices are larger and that trade is significantly less efficient in small-world networks as compared to random networks. Our second experimental finding is that location within a network is not an important determinant of pricing. An examination of the price dynamics suggests that traders on cheapest—and hence active—paths raise prices while those off these paths lower them. We construct an agent-based model (ABM) that embodies this rule of thumb. Simulations of this ABM yield macroscopic patterns consistent with the experimental findings. Finally, we extrapolate the ABM on to significantly larger random and small-world networks and find that network topology remains a key determinant of pricing and efficiency.

Hydrothermal Carbonization and Pellet Production from Egeria densa and Lemna minor

Biofuels are seen as a potential option for mitigating the effects of fossil fuel use. On the other hand, nutrient pollution is accelerating eutrophication rates in rivers, lakes, and coastal waters. Harvesting aquatic plants to produce biofuels could mitigate this problem, though it is important to attack the problem at source, mainly as regards the contribution of nutrients. For the first time, solid biofuels were obtained in the forms of carbon and pellets from the aquatic plants Egeria densa, which is classed as an invasive plant under the Spanish Catalogue of Exotic Invasive Species, and Lemna minor, both of which can be found in the Umia River in north-west Spain. The essential oils and macro- and microelements present in both these plants were also extracted and analyzed. The higher heating values (HHVs) of the carbon products obtained ranged from 14.28 to 17.25 MJ/kg. The ash content ranged from 22.69% to 49.57%. The maximum yield obtained for biochar for Egeria densa at 200 °C was 66.89%. Temperature significantly affects solid hydrochar yield. The HHVs of the pellets obtained ranged from 11.38 to 13.49 MJ/kg. The use of these species to obtain biofuels through hydrothermal carbonization (HTC) and pellets is a novel and effective approach that will facilitate the removal of nutrients that cause eutrophication in the Umia River. The elements extracted show that harvesting these plants will help to remove excessive nutrients from the ecosystem.

What Reasons Lead Spanish Medical Students Not to Be in Favor of Organ Donation?

INTRODUCTION

Despite sensitization of medical students toward the donation of organs, a non-negligible percentage of students are not in favor of donation.

OBJECTIVE

To analyze the reasons of Spanish medical students who do not have a favorable attitude toward the donation of their own organs after death.

METHOD

The population under study is medical students in Spanish universities, using the database of the International Donor Collaborative Project, stratified by geographic area and academic year. The questionnaire completion was anonymous and self-administered. The study group is medical students with an unfavorable attitude toward organ donation. The assessment instrument used is a validated questionnaire of attitude toward the donation of organs for transplant, "PCID-DTO-Ríos." The reasons against the donation are valued in the questionnaire through a question.

RESULTS

Of the participants included in the PCID, students who are not in favor of organ donation were selected (n = 1899). Of them, 8.1% (n = 154) are against and 91.1% (n = 1745) are doubtful. The main reasons indicated are the fear of apparent death in 11.4% of respondents, fear of possible mutilation after donation in 11.1%, and religious reasons in 2.6%. Of those, 6.9% indicate other reasons but do not clearly specify the reasons, using words such as "fear" (2.5%) or "doubts about the process" (4.1%); 66.2% (n = 1257) indicated an "assertive refusal" ("I don't want to express my reasons").

CONCLUSION

Twenty percent of Spanish medical students are not in favor of donating their organs and are not in favor of showing their reasons.

Factors Related to the Attitude Toward Living Kidney Donation of the Population of Havana

INTRODUCTION

Living kidney donation (LKD) is one of the most used alternatives in the field of organ transplantation.

OBJECTIVE

Analyze the attitude toward LKD among the population of Havana, Cuba.

METHODS

Population under study. Population resident in Havana, Cuba.

INCLUSION CRITERIA

Sample of population over 15 years stratified by age and sex.

INSTRUMENT

Validated questionnaire of attitude toward donation and transplant "PCID-DVR-Ríos," self-administered and anonymously filled out.

STATISTICS

χ², Student t test, and a logistic regression analysis.

RESULTS

A total of 920 respondents have been included in the study. A total of 85.5% (n = 787) are in favor of the related LKD. In our study, 26.5% (n = 244) would remain in favor of unrelated LKD. Regarding the related LKD, the following variables remain independent in the multivariate analysis: 1. having studies (odds ratio [OR] = 3.649; P = .018); 2. attitude toward cadaveric organ donation (OR = 8.547; P < .001); 3. religion (OR = 4.385; P = .001); 4. opinion of the couple (OR = 4.672; P = .028); and 5. risk with living donation (OR = 10.989; P = .003).

CONCLUSIONS

The population of Havana has a very favorable attitude toward related LKD. Only a quarter of respondents are in favor of unrelated LKD.

Are Medical Students of Non-Spanish Nationality Studying in Spain as Sensitized to Transplantation as Those of Spanish Nationality?

INTRODUCTION

Awareness of organ donation among Spanish doctors and medical students is very positive. However, the emerging group of professionals of non-Spanish nationality studying in Spain has not been analyzed.

OBJECTIVE

To analyze the differences in the attitudes toward the different types of donation among medical students, according to their nationality.

METHODS

The population under study is medical students in Spanish universities using the database of the International Collaborative Donor Project, stratified by geographic area and academic year. Groups under study include students of non-Spanish nationality as group 1 (n = 1570) and students of Spanish nationality as Group 2 (n = 7705). Instruments are validated questionnaires of attitude toward donation "PCID-DTO-Ríos," "PCID-DVR-Ríos," "PCID-DVH-Ríos," and "PCID-XenoTx-Ríos."

RESULTS

The attitude toward the donation of own organs after death is similar in both groups (P = .703). Non-Spaniards are 79.2% in favor compared to 79.6% of Spaniards. Living kidney donation, both unrelated (33.3% vs 29.3% in favor; P = .001) and related (91.2% vs 89, 6% in favor; P = .047), is more favorable among non-Spanish students. There are no differences regarding non-related living liver donation (29.7% vs 29.3% in favor; P = .063), but there are differences in the results for related living liver donation (94.1% vs 88%; P < .001). The attitude toward xenotransplantation of organs is similar (80.8% vs 80.8%; P = .999).

CONCLUSIONS

Awareness of the donation of organs among Spanish medical students is similar to non-Spanish students studying in Spain, except the attitude toward living donation.

Information About Donation and Organ Transplantation Among Spanish Medical Students

INTRODUCTION

Health professionals are asked to promote health, especially organ transplantation; however, they do not always have specific training.

OBJECTIVE

To analyze information about donation and organ transplantation among Spanish medical students.

METHOD

The population under study is medical students in Spanish universities using the database of the International Donor Collaborative Project, stratified by geographic area and academic year (n = 9275). The instrument used is the attitude questionnaire for organ donation for "PCID-DTO-Ríos" transplantation, validated with an explained variance of 63.203% and α = 0.834. The Student t test was applied together with the χ² test, complemented by an analysis of the remainders, and Fisher's exact test was applied.

RESULTS

Of the students, 74% indicate that they have received information from university professors about organ transplant. Concerning specific issues with the donation, it is notable that only 66.7% (n = 6190) know and accept the concept of brain death as the death of a person. However, only 22% consider themselves as having good information, and 35.3% indicate that their information is scarce or void. Students indicate having received information about transplant from other extra-university sources, such as television and Internet (80.9%), books and magazines (73.2%), and the press (66.9%). From the information obtained in the sociofamilial field, 60.7% have obtained information from the family and 58.1% from friends. Of this information, 9% has been negative from friends, 7.5% from family, 6% from the Internet and television, and 4% from university professors.

CONCLUSION

Spanish medical students believe they have little information about organ transplantation and have received negative information.

Sensitization Toward Organ Donation Among Medical Students in Spanish Regions With More Than 50 Donors Per Million Population

The awareness of organ donation among health professionals is important at the time of transplant promotion. In this sense, the training and awareness of the professionals in training is fundamental.

OBJECTIVE

To analyze the differences in the attitude toward organ donation and the factors that condition it among medical students of regions with donation rates >50 donors per million population (pmp) with respect to those with rates <40 donor pmp.

METHOD

Population under study: medical students in Spanish universities. Database of the Collaborative International Donor Project, stratified by geographic area and academic course. The completion was anonymous and self-administered. Groups under study: Group 1 (n = 1136): students in universities of regions with >50 donors pmp. Group 2 (n = 2018): university students in regions with <40 donors pmp. Assessment instrument: attitude questionnaire for organ donation for transplant PCID-DTO-Ríos.

RESULTS

The attitude toward organ donation for transplantation is similar among students from the autonomous communities with >50 donors pmp and with <40 donors pmp. In group 1, 79% (n = 897) of students are in favor compared with 81% (n = 1625) of group 2 (P=.29). The psychosocial profile toward donation is similar in both groups relating to the following variables (P < .05): sex, having discussed transplantation with family and as a couple, considering the possibility of needing a transplant, involvement in prosocial activities, attitude toward the manipulation of corpses, knowledge of the brain death concept, and religion.

CONCLUSIONS

The awareness of organ donation in Spanish medical students is quite homogeneous and is not related to the local donation rates of each region.

What Is the Attitude Toward Cadaveric Organ Donation of the Ghanian Residents in Spain?

INTRODUCTION

The Ghanaian population is migrating toward the European economic community, especially toward the southern countries.

OBJECTIVE

To analyze the attitude toward organ donation among the population born in Ghana but currently residing in Spain.

METHOD

The study included the population born in Ghana who are ≥ 15 years of age and residents of Spain, stratified by age and sex. The assessment instrument used is the donation and transplant attitude questionnaire of Proyecto Colaborativo Internacional Donante (PCID-DTO Ríos), which was self-administered and anonymously completed with verbal consent. The statistics used were descriptive, χ², Student t test, and a logistic regression analysis.

RESULTS

The questionnaire was completed by 237 Ghanaians. Forty-three percent (n = 102) are in favor of cadaveric organ donation, 35% (n = 83) are against donating their own organs, and 20% (n = 48) are undecided. In the multivariate analysis, the association was maintained at the level of the primary studies (P < .001, OR = 25), not being afraid of possible mutilation after donating (P < .001, OR = 76.923), religion (P < .001; OR = 27.777), performing prosocial activities (P = .016, OR = 12.048), and having previously commented on the issue of organ donation and transplantation in the family setting (P = .012, OR = 4.878).

CONCLUSIONS

The Ghanaian immigrant population in Spain has an unfavorable attitude toward the donation of their own organs at death, which is conditioned by multiple psychosocial factors.

Validation of the Attitude Toward Living Liver Donation Questionnaire (PCID-DVH-Ríos) in Spanish-Speaking Populations: Characteristics and Psychometric Properties

INTRODUCTION

Given the lack of a sufficient number of livers available for transplantation, living liver donation (LLD) is being developed in the Spanish-speaking world. Knowing the population's attitude toward this donation will help in designing more effective campaigns to increase the number of such donations. However, there are few validated questionnaires.

OBJECTIVE

To analyze the psychometric characteristics of questionnaire PCID-DVH-Ríos [questionnaire of the International Collaborative Donor Project about Living Liver Donation ("Proyecto Colaborativo Internacional Donante sobre Donación de Vivo Hepático" in Spanish) developed by Dr. Ríos, in order to validate the questionnaire for the Spanish-speaking population.

METHODS

The study population comprised native Spanish citizens. A sample of the population was obtained randomly and stratified by age and sex (N = 600) according to the following: 1. being older than 18 years; 2. being Spanish; and 3. living in Spain. Attitude was assessed using a validated questionnaire of attitude toward liver donation (PCID-DVH-Ríos). This questionnaire included items distributed into subscales or factors, an initial description of the data, an exploratory factor analysis, and an internal consistency analysis.

RESULTS

The questionnaire consists of a total of 11 items, distributed into 3 subscales: 1. factor 1 (6 items); 2. factor 2 (3 items); and 3. factor 3 (2 items), presenting a total explained variance of 63.995%. The factors have an explained variance of F1: 38.461%; F2: 14.228%; and F3: 11.306%, respectively. The analysis of items and internal consistency supported the 3 factors' composition. The internal consistency of each factor is as follows: α1 = 0.80; α2 = 0.70; and α3 = 0.55, respectively.

CONCLUSIONS

The dimensions analyzed in the PCID-DVH-Ríos questionnaire on attitudes toward living liver donation show a good fit in relation to their factorial validity and internal consistency values.

Emigration From Puerto Rico to Florida: Multivariate Analysis of Factors That Condition Attitudes of the Puerto Rican Population Toward Organ Donation for Transplant

BACKGROUND

The Puerto Rican population represents one of the largest immigration groups in Florida, and this has an impact on the organ transplant donation process. Our aim was to analyze attitudes toward organ donation among Puerto Ricans who currently reside in the state of Florida (USA).

METHODS

The population screened consisted of individuals >15 years old, who were born in Puerto Rico, living in Florida, and awaiting organs for transplant. All participants completed the "PCID-DTO Rios" questionnaire. Random selection was done according to stratification. Support from immigration associations in Spain was needed for advice on the locations of potential respondents. Study participation was anonymized and self-administered.

RESULTS

There were 259 respondents, 37% (n = 95) were in favor of donation, 36% (n = 93) were against donation, and 27% (n = 71) were undecided. The variables associated with these attitudes were: age (P = .017); civil status (P = .021); level of education (P < .001); previous experience with donation and transplant (P < .001); attitude toward organ donation of a relative (P < .001); carrying out pro-social activities (P < .001); discussing the issue of transplant with the family (P < .001) or couple (P < .001); attitude toward incineration (P < .001), burial (P < .001), and autopsy (P < .001); fear of mutilation after donation (P < .001); and religious beliefs (P < .001). In the multivariate study, it remained an independent variable to have discussed the issue at the family level (odds ratio = 11.627; P = .009).

CONCLUSION

The Puerto Rican study population residing in Florida has an unfavorable attitude toward organ donation.

Factors That Affect the Attitudes of the Bolivian Population in Spain With Regard to Organ Donation for Transplant

BACKGROUND

The Bolivian population is an emerging Latin American immigrant group in Spain, several of whom have been transplanted or are awaiting transplant. We aimed to assess attitudes toward organ donation among Bolivians currently residing in Spain.

METHOD

The population screened was born in Bolivia but living in Spain, stratified by gender and age. The appraisal tool used was a questionnaire that assesses attitudes toward organ donation for transplant ("PCID-DTO Ríos"). Support from immigration associations in Spain was needed for advice on locations of potential respondents. Survey participation was anonymized and the questionnaire was self-administered. Verbal consent was obtained before participation.

RESULTS

There were 206 respondents: 49% (n = 101) in favor of donating their organs after death; 21% (n = 44) against donation; and 30% (n = 61) undecided. Their attitudes were found to be associated with level of education (P = .008), previous experience with donation and transplant (P = .011), concern regarding mutilation after donation (P = .002), knowing the attitude of their religion toward transplant (P = .001), the opinion of their partner (P < .001), and the possibility of needing a future transplant (P = .050). In the multivariate study, the main factor was having a partner in favor of organ donation (odds ratio = 16.129; P = .003).

CONCLUSION

Attitudes toward organ donation among Bolivians residing in Spain are far more negative compared with rest of the Spanish population, due to various factors.

Multivariate Analysis of Factors That Influence the Attitude of the Ecuadorian Population Resident in Spain Toward Living-Related Kidney Donation

BACKGROUND

The Ecuadorian population is the largest Latin-American immigrant group in Spain. Currently, several Ecuadorians have received transplants or are awaiting transplants in Spain. The aim of this work was to analyze the attitude toward living kidney donation among the Ecuadorian population residing in Spain.

METHODS

The population screened were born in Ecuador, residing in Spain, and >15 years old, stratified by gender and age, and appraised with the use of the questionnaire on attitude toward organ donation for transplantation "PCID-DVR-Ríos." Support from immigration associations in Spain was used to advise on the location of potential respondents. The completion was anonymous and self-administered. Verbal consent was obtained. Statistics included Student t test, χ², Fisher exact test, and logistic regression analysis.

RESULTS

A total of 461 respondents were included: 80% (n = 367) were in favor of living-related kidney donation (for a relative or close friend). This attitude was associated with psychosocial variables that persisted in the multivariate study: 1) female gender (odds ratio [OR], 3.086; P = .001); 2) considering oneself a potential kidney receptor in the future (OR, 16.949; P = .002); 3) economic incentive in the donation (OR, 100; P = .004); and 4) knowing the attitude of their religion toward transplantation (OR, 32.258; P < .001).

CONCLUSIONS

Living-related donation is accepted among the Ecuadorian population residing in Spain and is associated with sociopersonal and religious factors.

Attitude Toward Organ and Tissue Xenotransplantation Questionnaire (PCID-XENOTx-Ríos): Characteristics and Psychometric Properties of the Validation in Spanish-Speaking Populations

INTRODUCTION

Making xenotransplantation socially acceptable is the first step in working toward the promotion of this potential therapy option for providing transplant organs. However, most of the questionnaires used for this task are not validated.

OBJECTIVE

To analyze the psychometric characteristics of the questionnaire of attitud toward xenotransplantation PCID-XENOTx-Ríos (Questionnaire of Proyecto Colaborativo Internacional Donante about Xenotransplantation developed by Dr. Ríos) to validate the questionnaire in the Spanish speaking population.

METHODS

The study population was the native Spanish population living in southeast Spain. A sample of the population was obtained randomly and stratified by age and sex (N = 600), using the following inclusion criteria: 1. being older than 18 years; 2. being Spanish; and 3. living in Spain. Instrument valuation. Attitude was assessed using the validated PCID-XENOTx-Ríos questionnaire to gauge attitudes toward organ and tissue xenotransplantation. The statistical analysis included an initial description of the data, an exploratory factor analysis, an items analysis, and an internal consistency analysis.

RESULTS

The questionnaire consists of a total of 30 items, distributed in 4 subscales: 1. Factor 1: consequences (11 items); 2. Factor 2: associated risks (7 items); 3. Factor 3: transmission of infections (6 items); and 4. Factor 4: origins of transplantation (6 items). This structure presents a total explained variance of 61.18%. The internal consistency of each factor was as follows: α1 = 0.91; α2 = 0.92; α3 = 0.89; and α4 = 0.72. The analysis of items and internal consistency supported the 4 factors' composition.

CONCLUSIONS

Dimensions analyzed in the PCID-XENOTx-Ríos questionnaire of attitudes toward organ and tissue xenotransplantation show a good fit in relation to their factorial validity and internal consistency values.

Attitude of the Citizens of Havana, Cuba, Toward Organ Donation: A Multivariate Analysis of the Psychosocial Factors Affecting Attitude

INTRODUCTION

Because personal decisions affect the availability of organs for transplants, awareness about organ donations among the general population is fundamental.

OBJECTIVE

To analyze attitudes toward organ donation among the citizens of Havana, Cuba.

METHODS

The sample population was the residents of the city of Havana, Cuba. The inclusion criterion was being older than 15 years; the sample was obtained randomly and stratified by age and sex. Attitude was assessed using a validated questionnaire on psychosocial aspects of organ donation and transplant (PCID-DTO-Ríos). A random selection of people to be surveyed was carried out.

RESULTS

A sample of 920 respondents was included in the study. Attitude toward cadaveric donation was favorable in 68% of respondents, while 14% were against and 18% were undecided. Several variables were associated with having a more favorable attitude. In the multivariate analysis, the following variables continue to feature as independent variables (P <  .05): 1. level of studies; 2. knowledge of the concept of brain death; 3. attitude toward organ donation of a relative; 4. having discussed the issue of organ donation and transplantation with one's family; 5. the attitude of the couple toward organ donation and transplantation; 6. the religion of the respondent; 7. knowing the opinion of one's religion toward organ transplantation; 8. fear of manipulation of the body after death; and 9. acceptance of burial as a treatment of the body after the death.

CONCLUSIONS

The attitude toward cadaveric organ donation among the residents of Havana is favorable and similar to that of the citizens of Spain. Improving the organ procurement system will increase donation rates given the population's awareness of the issue.

Freshwater algae competition and correlation between their growth and microcystin production

There are some different freshwater algae in Eutrophic reservoirs which bloom with specific environmental conditions, and some of them are cyanobacteria. In this investigation, we have cultivated microalgae present in natural water samples from a eutrophic reservoir. Variations in temperature and light were evaluated, as well as the competition among different green algae and cyanobacteria. There were three different freshwater algae growing together, Scenedesmus sp., Kirchneriella sp. and Microcystis aeruginosa, this cyanobacterium was the algae that reached the highest development and growth during the culture. While the algae grew, the concentration of toxin (microcystin-LR) increased until it reached the highest levels at 570 μg g^-1. Blooms occurred at temperatures of 28 ± 1.5 °C and light cycles of longer hours of light than dark. This took place during the summer months, from June to September (in the study area). At temperatures below 18 °C, algae did not grow. Blooms were reproduced to a laboratory scale in different conditions in order to understand the development of freshwater algae, as well as to help decision-making about water supply from that reservoir.

Mechanisms of triple whammy acute kidney injury

Pre-renal acute kidney injury (AKI) results from glomerular haemodynamic alterations leading to reduced glomerular filtration rate (GFR) with no parenchymal compromise. Renin-angiotensin system inhibitors, such as angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor antagonists (ARAs), non-steroidal anti-inflammatory drugs (NSAIDs) and diuretics, are highly prescribed drugs that are frequently administered together. Double and triple associations have been correlated with increased pre-renal AKI incidence, termed "double whammy" and "triple whammy", respectively. This article presents an integrative analysis of the complex interplay among the effects of NSAIDs, ACEIs/ARAs and diuretics, acting alone and together in double and triple therapies. In addition, we explore how these drug combinations alter the equilibrium of regulatory mechanisms controlling blood pressure (renal perfusion pressure) and GFR to increase the odds of inducing AKI through the concomitant reduction of blood pressure and distortion of renal autoregulation. Using this knowledge, we propose a more general model of pre-renal AKI based on a multi whammy model, whereby several factors are necessary to effectively reduce net filtration. The triple whammy was the only model associated with pre-renal AKI accompanied by a course of other risk factors, among numerous potential combinations of clinical circumstances causing hypoperfusion in which renal autoregulation is not operative or is deregulated. These factors would uncouple the normal BP-GFR relationship, where lower GFR values are obtained at every BP value.

Pellets valorization of waste biomass harvested by coagulation of freshwater algae

There is a comparison of different coagulants: calcium chloride (20, 60, 120 and 180 mg/L); sodium alginate (10 and 20 mg/L) and tannins of Eucalyptus globulus bark (10 and 20 mg/L) in order to make the most of each method. The results show that 20 mg/L of tannin achieved a recovery efficiency of 95.35±1.16, sodium alginate 90.49±0.53 and 84.04±2.29 for calcium chloride. Taking into account the economic side of the coagulants, obtaining tannins is a profitable process. Bark is waste biomass obtained in the forestry process; therefore it does not involve extra costs. Finally, the feasibility of making pellets from harvested algae was studied, and the results suggest that waste biomass pellets may be used as fuel in boilers in a mixture <54% with other waste sources as Eucalyptus g. branches.

Harvesting green algae from eutrophic reservoir by electroflocculation and post-use for biodiesel production

Each year there are more frequent blooms of green algae and cyanobacteria, representing a serious environmental problem of eutrophication. Electroflocculation (EF) was studied to harvest the algae which are present in reservoirs, as well as different factors which may influence on the effectiveness of the process: the voltage applied to the culture medium, run times, electrodes separation and natural sedimentation. Finally, the viability of its use to obtain biodiesel was studied by direct transesterification. The EF process carried out at 10V for 1min, with an electrode separation of 5.5cm and a height of 4cm in culture vessel, obtained a recovery efficiency greater than 95%, and octadecenoic and palmitic acids were obtained as the fatty acid methyl esters (FAMEs). EF is an effective method to harvest green algae during the blooms, obtaining the greatest amount of biomass for subsequent use as a source of biodiesel.

High-frequency phase shift measurement greatly enhances the sensitivity of QCM immunosensors

In spite of being widely used for in liquid biosensing applications, sensitivity improvement of conventional (5-20MHz) quartz crystal microbalance (QCM) sensors remains an unsolved challenging task. With the help of a new electronic characterization approach based on phase change measurements at a constant fixed frequency, a highly sensitive and versatile high fundamental frequency (HFF) QCM immunosensor has successfully been developed and tested for its use in pesticide (carbaryl and thiabendazole) analysis. The analytical performance of several immunosensors was compared in competitive immunoassays taking carbaryl insecticide as the model analyte. The highest sensitivity was exhibited by the 100MHz HFF-QCM carbaryl immunosensor. When results were compared with those reported for 9MHz QCM, analytical parameters clearly showed an improvement of one order of magnitude for sensitivity (estimated as the I50 value) and two orders of magnitude for the limit of detection (LOD): 30μgl(-1) vs 0.66μgL(-1)I50 value and 11μgL(-1) vs 0.14μgL(-1) LOD, for 9 and 100MHz, respectively. For the fungicide thiabendazole, I50 value was roughly the same as that previously reported for SPR under the same biochemical conditions, whereas LOD improved by a factor of 2. The analytical performance achieved by high frequency QCM immunosensors surpassed those of conventional QCM and SPR, closely approaching the most sensitive ELISAs. The developed 100MHz QCM immunosensor strongly improves sensitivity in biosensing, and therefore can be considered as a very promising new analytical tool for in liquid applications where highly sensitive detection is required.

Retrieval of noisy fingerprint patterns using metric attractor networks

This work experimentally analyzes the learning and retrieval capabilities of the diluted metric attractor neural network when applied to collections of fingerprint images. The computational cost of the network decreases with the dilution, so we can increase the region of interest to cover almost the complete fingerprint. The network retrieval was successfully tested for different noisy configurations of the fingerprints, and proved to be robust with a large basin of attraction. We showed that network topologies with a 2D-Grid arrangement adapt better to the fingerprints spatial structure, outperforming the typical 1D-Ring configuration. An optimal ratio of local connections to random shortcuts that better represent the intrinsic spatial structure of the fingerprints was found, and its influence on the retrieval quality was characterized in a phase diagram. Since the present model is a set of nonlinear equations, it is possible to go beyond the naïve static solution (consisting in matching two fingerprints using a fixed distance threshold value), and a crossing evolution of similarities was shown, leading to the retrieval of the right fingerprint from an apparently more distant candidate. This feature could be very useful for fingerprint verification to discriminate between fingerprints pairs.