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1.
Sci Rep ; 13(1): 19090, 2023 Nov 04.
Article in English | MEDLINE | ID: mdl-37925527

ABSTRACT

This work focuses on the [Formula: see text]-anonymity of some networks as a measure of their privacy against active attacks. Two different types of networks are considered. The first one consists of graphs with a predetermined structure, namely cylinders, toruses, and 2-dimensional Hamming graphs, whereas the second one is formed by randomly generated graphs. In order to evaluate the [Formula: see text]-anonymity of the considered graphs, we have computed their k-metric antidimension. To this end, we have taken a combinatorial approach for the graphs with a predetermined structure, whereas for randomly generated graphs we have developed an integer programming formulation and computationally tested its implementation. The results of the combinatorial approach, as well as those from the implementations indicate that, according to the [Formula: see text]-anonymity measure, only the 2-dimensional Hamming graphs and some general random dense graphs are achieving some higher privacy properties.

2.
Malar J ; 20(1): 241, 2021 May 29.
Article in English | MEDLINE | ID: mdl-34051817

ABSTRACT

BACKGROUND: To reduce the malaria burden and improve the socioeconomic status of its citizens, the Democratic Republic of Congo scaled up key malaria control interventions, especially insecticide-treated nets (ITNs), between 2005 and 2014. Since then, the effects of these interventions on malaria mortality and morbidity have not been assessed. This study aimed to measure the impact of the National Malaria Control Programme's efforts and to inform future control strategies. METHODS: The authors used data from the Demographic and Health Surveys 2007 and 2013-2014 to assess trends in all-cause childhood mortality (ACCM) against trends in coverage of malaria interventions at national and subnational levels. The authors used the plausibility argument to assess the impact of the malaria control interventions and used Kaplan-Meier survival probability and Cox proportional hazard models to examine the effect of ITN ownership on child survival. Contextual factor trends affecting child survival were also considered. RESULTS: Countrywide, household ownership of at least one ITN increased, from 9% in 2007 to 70% in 2013-2014. All provinces experienced similar increases, with some greater than the national level. ITN use increased between 2007 and 2013-2014 among children under five (6% to 55%). Severe anaemia (haemoglobin concentration < 8 g/dl) prevalence among children aged 6-59 months significantly decreased, from 11% (95% confidence interval [CI] 9-13%) in 2007 to 6% (95% CI 5-7%) in 2013-2014. During the same period, ACCM declined, from 148 (95% CI 132-163) to 104 (95% CI 97-112) deaths per 1000 live births. The decline in ACCM was greater among children aged 6-23 months (relative reduction of 36%), compared to children aged 24-59 months (relative reduction of 12%). Cox regression indicated that household ownership of at least one ITN reduced the risk of mortality by 24% among children under five (risk ratio = 0.76, 95% CI 0.64-0.90). Contextual factor analysis revealed marginal improvements in socioeconomic indicators and other health interventions. CONCLUSIONS: Given the patterns of the coverage of malaria control interventions, patterns in ACCM by province, and marginal improvements in contextual factors, the authors conclude that the malaria control interventions have plausibly contributed to the decrease in ACCM in the Democratic Republic of Congo from 2005 to 2014.


Subject(s)
Child Mortality/trends , Insecticide-Treated Bednets/statistics & numerical data , Malaria/prevention & control , Morbidity/trends , Mosquito Control/statistics & numerical data , Child, Preschool , Democratic Republic of the Congo/epidemiology , Female , Humans , Infant , Infant, Newborn , Malaria/mortality , Male , Prevalence
3.
Minerva ; 59(1): 79-98, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33664532

ABSTRACT

Over the course of the 20th century, unprecedented growth in scientific discovery was fueled by broad growth in the number of university-based scientists. During this period the American undergraduate enrollment rate and number of universities with STEM graduate programs each doubled three times and the annual volume of new PhDs doubled six times. This generated the research capacity that allowed the United States to surpass early European-dominated science production and lead for the rest of the century. Here, we focus on origins in the organizational environment and institutional dynamics instead of conventional economic factors. We argue that three trends of such dynamics in the development of American higher education not often considered together-mass undergraduate education, decentralized founding of universities, and flexible mission charters for PhD training-form a process characterized by a term coined here: access symbiosis. Then using a 90-year data series on STEM PhD production and institutional development, we demonstrate the historical progression of these mutually beneficial trends. This access symbiosis in the U.S., and perhaps versions of it in other nations, is likely one critical component of the integration of higher education development with the growing global capacity for scientific discovery. These results are discussed in terms of the contributions of American universities to the Century of Science, recent international trends, and its future viability.

4.
SSM Ment Health ; 12021 Dec.
Article in English | MEDLINE | ID: mdl-38571576

ABSTRACT

This study builds on a growing body of literature analyzing the education-health gradient across detailed educational categories, which documents that US working-age adults who attended college but did not earn a bachelor's degree report equal or worse health than adults with a high school diploma. This is known as the "anomaly" in the education-health gradient. The purpose of this study is to test whether this pattern extends to measures of serious psychological distress (SPD) and individual symptoms by using data from the National Health Interview Survey (NHIS, 1997-2018) and a series of logistic regression models. We find that the anomaly in the education-health gradient is present for a summary measure of SPD as well as for five of the six symptoms that make up this measure. The exception was reporting feeling sad most or all the time during the last month, where adults with "some college" were found to have lower odds than those with a high school diploma. Further stratified analysis by sex revealed that this result for feeling sad was driven by women. In terms of associate degrees, our models show that adults with a vocational/technical associate degree have statically similar odds of SPD and reporting four out of six symptoms (exceptions were feeling hopeless and sadness), while those with an academic associate degree have significantly lower odds in all outcomes. The robustness of the models used is supported by an extensive sensitivity analysis. Overall, we find evidence of the anomaly in the education-health gradient in SPD and individual symptoms of psychological distress at the sub-baccalaureate level, adding to previous studies that document the anomaly in markers of physiological dysregulation, health conditions, vision problems, functional limitations, and pain.

5.
Int Perspect Sex Reprod Health ; 46: 113-124, 2020 07 09.
Article in English | MEDLINE | ID: mdl-32701061

ABSTRACT

CONTEXT: Little is known about the pathways mediating the relationship between education and health. It is widely assumed that formal schooling leads to awareness of health risks (e.g., STIs) and, in turn, to adoption of preventive behavior (e.g., condom use); however, evidence supporting this mechanism has been limited. METHODS: Survey data were collected in 2010 from a sample of 247 adults aged 30-62 living in an isolated Andean district of Peru; these individuals had widely varying exposure to schooling, and their community had recently experienced elevated risks of STIs. Structural equation modeling was used to estimate the degree to which schooling is associated with cognitive resources, STI awareness and sexual health knowledge, and how these jointly are associated with ever-use of condoms. RESULTS: Thirty-two percent of respondents reported ever-use of condoms. One additional year of schooling was associated with a 2.7-percentage-point increase in the probability of condom use, after adjustment for covariates. The pathway between education and condom use was mediated by cognitive executive functioning (CEF) skills (0.26 standard deviations), STI awareness (0.09) and sexual health knowledge (0.10); CEF skills were associated with condom use both directly and indirectly, through STI awareness and sexual health knowledge, and accounted for two-thirds of the education-condom use gradient. CONCLUSIONS: The relationship between education and STI prevention may be more complex than is often assumed and is mediated by CEF skills, STI awareness and sexual health knowledge. Studies should examine whether STI prevention interventions are more effective if they enhance cognitive skills used to translate information into protective behaviors.


RESUMEN Contexto: Se sabe poco acerca de las vías que median la relación entre el nivel educativo y la salud. Generalmente se supone que la escolaridad formal conduce a la conciencia de los riesgos para la salud (por ejemplo, las ITS) y, a su vez, a la adopción de un comportamiento preventivo (por ejemplo, el uso del condón); sin embargo, la evidencia que apoya este mecanismo ha sido limitada. Métodos: Los datos de la encuesta se obtuvieron en 2010 de una muestra de 247 adultos de 30 a 62 años que vivían en un distrito andino aislado de Perú; estas personas tenían una exposición muy variable a la escolaridad y su comunidad había experimentado recientemente riesgos elevados de ITS. Se usó el modelo de ecuaciones estructurales para estimar el grado en que la escolaridad se asociaba con los recursos cognitivos, la conciencia de las ITS y el conocimiento de la salud sexual y cómo estos se asocian conjuntamente con el haber usado alguna vez condones. Resultados: El treinta y dos por ciento de los encuestados informaron que alguna vez usaron condones. Un año adicional de escolaridad se asoció con un aumento de 2.7 puntos porcentuales en la probabilidad de uso del condón, después del ajuste por covariables. La vía entre el nivel educativo y el uso del condón estuvo mediada por las habilidades de funcionamiento cognitivo ejecutivo (FCE) (0.26 desviaciones estándar), conciencia de las ITS (0.09) y conocimiento de salud sexual (0.10); Las habilidades de FCE se asociaron con el uso del condón tanto directa como indirectamente, a través de la conciencia de las ITS y los conocimientos sobre salud sexual y representaron dos tercios del gradiente educativo del uso del condón. Conclusiones: La relación entre el nivel educativo y la prevención de las ITS podría ser más compleja de lo que a menudo se supone y está mediada por las habilidades de FCE, la conciencia de las ITS y el conocimiento de la salud sexual. Los estudios deben examinar si las intervenciones de prevención de ITS son más efectivas si mejoran las habilidades cognitivas utilizadas para traducir la información en comportamientos protectores.


RÉSUMÉ Contexte: Les voies de médiation de la relation entre l'éducation et la santé ne sont guère documentées. Il est généralement présumé que la scolarité mène à la conscience des risques de santé (par ex., les IST), qui conduit à son tour à l'adoption d'un comportement préventif (par ex., l'utilisation du préservatif). Les données qui appuient ce mécanisme sont cependant limitées. Méthodes: Des données d'enquête ont été collectées en 2010 auprès d'un échantillon de 247 adultes de 30 à 62 ans vivant dans un district andin isolé du Pérou. Ces personnes présentaient une exposition fort variable à la scolarité et leur communauté était depuis peu confrontée à un risque élevé d'IST. La modélisation par équation structurelle a permis d'estimer le degré d'association entre, d'une part, la scolarité et, d'autre part, les ressources cognitives, la conscience des IST et la connaissance en matière de santé sexuelle, ainsi que de déterminer l'association globale de ces éléments avec le fait d'avoir déjà utilisé le préservatif. Résultats: Trente-deux pour cent des répondants ont déclaré avoir utilisé le préservatif. Chaque année supplémentaire de scolarité s'est avérée associée à une augmentation de 2,7 points de pourcentage de la probabilité d'usage du préservatif, sous correction des covariables. Le lien entre l'éducation et l'utilisation du préservatif était induit par les compétences de fonctionnement exécutif cognitif (FEC) (écarts types de 0,26), la conscience des IST (0,09) et la connaissance en matière de santé sexuelle (0,10). Les compétences FEC étaient associées à l'utilisation du préservatif de façon directe et indirecte, du fait de la conscience des IST et de la connaissance en matière de santé sexuelle; elles représentaient deux tiers du gradient éducation-utilisation du préservatif. Conclusions: La relation entre l'éducation et la prévention des IST peut être plus complexe qu'on ne le pense souvent. Elle est induite par les compétences FEC, la conscience des IST et la connaissance en matière de santé sexuelle. Il serait utile d'examiner si les interventions de prévention des IST sont plus efficaces quand elles améliorent les compétences cognitives qui traduisent l'information en comportements de protection.


Subject(s)
Condoms/statistics & numerical data , Contraception Behavior/statistics & numerical data , Educational Status , Health Knowledge, Attitudes, Practice , Sexually Transmitted Diseases/prevention & control , Sexually Transmitted Diseases/psychology , Adult , Cognition , Executive Function , Female , Humans , Male , Middle Aged , Peru , Surveys and Questionnaires
6.
Nanoscale Adv ; 2(8): 3156-3163, 2020 Aug 11.
Article in English | MEDLINE | ID: mdl-36134291

ABSTRACT

Graphene, with its excellent electrical, mechanical, and optical properties, has emerged as an exceptional material for flexible and transparent nanoelectronics. Such versatility makes it compelling to find new pathways to lay graphene sheets onto smooth, flexible substrates to create large-scale flexible transparent graphene conductors. Here, we report the realization of flexible transparent graphene laminates by direct adhesion of chemical vapor deposition (CVD) graphene on a polyethylene naphthalate (PEN) substrate, which is an emerging standard for flexible electronics. By systematically optimizing the conditions of a hot-press technique, we have identified that applying optimum temperature and pressure can make graphene directly adhere to flexible PEN substrates without any intermediate layer. The resultant flexible graphene films are transparent, have a standard sheet resistance of 1 kΩ with high bending resilience, and high optical transmittance of 85%. Our direct hot-press method is achieved below the glass transition temperature of the PEN substrate. Furthermore, we demonstrate press-assisted embossing for patterned transfer of graphene, and hence it can serve as a reliable new means for creating universal, transparent conducting patterned films for designing flexible nanoelectronic and optoelectronic components.

7.
Oxid Med Cell Longev ; 2019: 1983137, 2019.
Article in English | MEDLINE | ID: mdl-31827669

ABSTRACT

Ethnomedicinal studies in the Amazon community and in the Northeast region of Brazil highlight the use of Libidibia ferrea fruits for the treatment of gastric problems. However, there are no data in the literature of this pharmacological activity. Thus, the aim of this paper is to provide a scientific basis for the use of the dry extract of L. ferrea pods (DELfp) for the treatment of peptic ulcers. Phytochemical characterization was performed by HPLC/MS. In vitro antioxidant activity was assessed using DPPH, ABTS, phosphomolybdenum, and superoxide radical scavenging activity. The gastroprotective activity, the ability to stimulate mucus production, the antisecretory activity, and the influence of -SH and NO compounds on the antiulcerogenic activity of DELfp were evaluated. The healing activity was determined by the acetic acid-induced chronic ulcer model. Anti-Helicobacter pylori activity was investigated. HPLC/MS results identified the presence of phenolic compounds, gallic acid and ellagic acid, in DELfp. The extract showed antioxidant activity in vitro. In ulcers induced by absolute ethanol and acidified ethanol, the ED50 values of DELfp were 113 and 185.7 mg/kg, respectively. DELfp (100, 200, and 400 mg/kg) inhibited indomethacin-induced lesions by 66.7, 69.6, and 65.8%, respectively. DELfp (200 mg/kg) reduced gastric secretion and H+ concentration in the gastric contents and showed to be independent of nitric oxide (NO) and dependent on sulfhydryl (-SH) compounds in the protection of the gastric mucosa. In the chronic ulcer model, DELfp reduced the area of the gastric lesion. DELfp also showed anti-H. pylori activity. In conclusion, DELfp showed antioxidant, gastroprotective, healing, and antiulcerogenic activities. The mechanism of these actions seems to be mediated by different pathways and involves the reduction of gastric secretion and H+ concentration, dependence on sulfhydryl compounds, and anti-H. pylori activity. All these actions support the medicinal use of this species in the management of peptic ulcers.


Subject(s)
Anti-Ulcer Agents/chemistry , Antioxidants/chemistry , Fabaceae/chemistry , Plant Extracts/chemistry , Acetic Acid/toxicity , Animals , Anti-Ulcer Agents/pharmacology , Anti-Ulcer Agents/therapeutic use , Chromatography, High Pressure Liquid , Fabaceae/metabolism , Female , Gastric Mucosa/drug effects , Gastric Mucosa/pathology , Helicobacter pylori/drug effects , Mass Spectrometry , Nitric Oxide/chemistry , Nitric Oxide/metabolism , Phenols/analysis , Plant Extracts/pharmacology , Rats , Rats, Wistar , Stomach Ulcer/chemically induced , Stomach Ulcer/drug therapy , Stomach Ulcer/pathology , Sulfhydryl Compounds/chemistry , Sulfhydryl Compounds/metabolism
8.
Br J Surg ; 105(10): 1359-1367, 2018 09.
Article in English | MEDLINE | ID: mdl-29663330

ABSTRACT

BACKGROUND: Decreasing anastomotic leak rates remain a major goal in colorectal surgery. Assessing intraoperative perfusion by indocyanine green (ICG) with near-infrared (NIR) visualization may assist in selection of intestinal transection level and subsequent anastomotic vascular sufficiency. This study examined the use of NIR-ICG imaging in colorectal surgery. METHODS: This was a prospective phase II study (NCT02459405) of non-selected patients undergoing any elective colorectal operation with anastomosis over a 3-year interval in three tertiary hospitals. A standard protocol was followed to assess NIR-ICG perfusion before and after anastomosis construction in comparison with standard operator visual assessment alone. RESULTS: Five hundred and four patients (median age 64 years, 279 men) having surgery for neoplastic (330) and benign (174) pathology were studied. Some 425 operations (85·3 per cent) were started laparoscopically, with a conversion rate of 5·9 per cent. In all, 220 patients (43·7 per cent) underwent high anterior resection or reversal of Hartmann's operation, and 90 (17·9 per cent) low anterior resection. ICG angiography was achieved in every patient, with a median interval of 29 s to visualization of the signal after injection. NIR-ICG assessment resulted in a change in the site of bowel division in 29 patients (5·8 per cent) with no subsequent leaks in these patients. Leak rates were 2·4 per cent overall (12 of 504), 2·6 per cent for colorectal anastomoses and 3 per cent for low anterior resection. When NIR-ICG imaging was used, the anastomotic leak rates were lower than those in the participating centres from over 1000 similar operations performed with identical technique but without NIR-ICG technology. CONCLUSION: Routine NIR-ICG assessment in patients undergoing elective colorectal surgery is feasible. NIR-ICG use may change intraoperative decisions, which may lead to a reduction in anastomotic leak rates.


Subject(s)
Anastomotic Leak/prevention & control , Colectomy , Elective Surgical Procedures , Intraoperative Care/methods , Proctectomy , Spectroscopy, Near-Infrared , Adolescent , Adult , Aged , Aged, 80 and over , Anastomosis, Surgical , Anastomotic Leak/epidemiology , Female , Fluorescent Dyes , Humans , Indocyanine Green , Male , Middle Aged , Prospective Studies , Treatment Outcome , Young Adult
9.
Demography ; 54(5): 1873-1895, 2017 10.
Article in English | MEDLINE | ID: mdl-28875332

ABSTRACT

The salutary effect of formal education on health-risk behaviors and mortality is extensively documented: ceteris paribus, greater educational attainment leads to healthier lives and longevity. Even though the epidemiological evidence has strongly indicated formal education as a leading "social vaccine," there is intermittent reporting of counter-education gradients for health-risk behavior and associated outcomes for certain populations during specific periods. How can education have both beneficial and harmful effects on health, and under which contexts do particular effects emerge? It is useful to conceptualize the influence of education as a process sensitive to the nature, timing of entry, and uniqueness of a new pleasurable and desirable lifestyle and/or product (such as smoking) with initially unclear health risks for populations. Developed herein is a hypothesis that the education gradient comprises multiple potent pathways (material, psychological, cognitive) by which health-risk behaviors are influenced, and that there can be circumstances under which pathways act in opposite directions or are differentially suppressed and enhanced. We propose the population education transition (PET) curve as a unifying functional form to predict shifting education gradients across the onset and course of a population's exposure to new health risks and their associated consequences. Then, we estimate PET curves for cases with prior epidemiological evidence of heterogeneous education gradients with health-risk behaviors related to mass-produced cigarettes in China and the United States; saturated fats, sugar, and processed food diets in Latin America; and HIV infection in sub-Saharan Africa. Each offers speculation on interactions between environmental factors during population exposure and education pathways to health-risk behaviors that could be responsible for the temporal dynamics of PET curves. Past epidemiological studies reporting either negative or positive education gradients may not represent contradictory findings as much as come from analyses unintentionally limited to just one part of the PET process. Last, the PET curve formulation offers richer nuances about educational pathways, macro-historical population dynamics, and the fundamental cause of disease paradigm.


Subject(s)
Educational Status , Health Behavior , Adolescent , Adult , Africa South of the Sahara/epidemiology , China/epidemiology , Diet , Education , Fatty Acids , Female , HIV Infections/epidemiology , Health Status , Humans , Latin America , Male , Middle Aged , Regression Analysis , Risk Factors , Risk-Taking , Smoking/epidemiology , Surveys and Questionnaires , Tanzania/epidemiology , Tobacco Products/supply & distribution , Uganda/epidemiology , United States/epidemiology , Young Adult
11.
Ann Oncol ; 26(2): 320-5, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25403587

ABSTRACT

BACKGROUND: HannaH (NCT00950300) was a phase III, randomized, international, open-label study that compared pharmacokinetics (PK), efficacy, and safety of two different trastuzumab formulations [subcutaneous (s.c.) and intravenous (i.v.)] in HER2-positive, operable, locally advanced, or inflammatory breast cancer in the neoadjuvant/adjuvant setting. The co-primary end points, to show noninferiority of s.c. versus i.v. trastuzumab in terms of serum concentration (Ctrough) and pathologic complete response (pCR) were met; safety profiles were comparable at 12 months' median follow-up. Secondary end points included safety and tolerability, PK profile, immunogenicity, and event-free survival (EFS). We now report updated safety and efficacy data after a median follow-up of 20 months. PATIENTS AND METHODS: Patients (N = 596) were treated with eight cycles of neoadjuvant chemotherapy, administered concurrently with 3-weekly s.c. trastuzumab (fixed dose of 600 mg) or the standard weight-based i.v. method. Following surgery, patients continued trastuzumab treatment to complete 1 year of therapy. Updated analyses of PK, efficacy, safety, and immunogenicity data were carried out. RESULTS: s.c. trastuzumab was generally well tolerated and the incidence of adverse events (AEs), including grade 3 or 4 AEs, between treatment groups was comparable. A slightly higher incidence of serious AEs (SAEs), mainly due to infections, was reported with s.c. treatment {64 [21.5%; 95% confidence interval (CI) 17.0%-26.7%] versus 42 (14.1%; 95% CI 10.4%-18.6%) in the i.v. group}; however, the differences were small and often based on rare events, with no observable pattern across reported events. An early analysis of EFS showed rates of 95% in both groups 1 year postrandomization. Exploratory analyses did not reveal an association between toxicity and body weight or exposure. CONCLUSIONS: Overall, the safety profile of s.c. trastuzumab was consistent with the previously published data from HannaH and the known safety profile of i.v. trastuzumab. EFS rates were comparable between the i.v. and s.c. groups. CLINICAL TRIAL NUMBER: NCT00950300.


Subject(s)
Antineoplastic Agents/administration & dosage , Breast Neoplasms/drug therapy , Trastuzumab/administration & dosage , Adult , Antineoplastic Agents/adverse effects , Antineoplastic Agents/pharmacokinetics , Breast Neoplasms/genetics , Female , Humans , Infusions, Intravenous , Injections, Subcutaneous , Middle Aged , Receptor, ErbB-2/biosynthesis , Receptor, ErbB-2/genetics , Trastuzumab/adverse effects
12.
Int J Gynecol Cancer ; 17(2): 316-24, 2007.
Article in English | MEDLINE | ID: mdl-17362309

ABSTRACT

Ovarian carcinosarcomas (OCS), also known as malignant mixed müllerian tumors, are uncommon malignancies that carry a poor prognosis. The presentation of OCS is usually indistinguishable from that of epithelial ovarian cancer. Due to its low frequency, prospective trials have been difficult to perform, but there is evidence that OCS are sensitive to platinum-based chemotherapy. Recent studies have shown encouraging results with platinum-ifosfamide and platinum-taxane schedules, which are usually considered the treatment of choice. However, poor performance status at presentation is also a common problem, so that many patients may be unsuitable for combination chemotherapy but may still benefit from single-agent platinum or ifosfamide or, occasionally, from nonplatinum schedules such as ifosfamide plus paclitaxel. Aggressive cytoreductive surgery appears to have a positive impact on outcome and should probably be offered to most patients. However, this procedure has been associated with higher rates of complication in OCS and should only be attempted by experienced (gynecological) surgeons in centers with expertise in the management of gynecological malignancies.


Subject(s)
Carcinosarcoma/therapy , Ovarian Neoplasms/therapy , Antineoplastic Agents/therapeutic use , Carcinosarcoma/diagnosis , Carcinosarcoma/etiology , Clinical Trials as Topic , Female , Humans , Ovarian Neoplasms/diagnosis , Ovarian Neoplasms/etiology , Prognosis
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