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Genetic and epigenetic targets of natural dietary compounds as anti-Alzheimer's agents 被引量:1
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作者 Willian Orlando Castillo-Ordoñez Nohelia Cajas-Salazar Mayra Alejandra Velasco-Reyes 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期846-854,共9页
Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older adults.Pathogenic factors,such as oxidative stress,an increase in acetylcholinester... Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older adults.Pathogenic factors,such as oxidative stress,an increase in acetylcholinesterase activity,mitochondrial dysfunction,genotoxicity,and neuroinflammation are present in this syndrome,which leads to neurodegeneration.Neurodegenerative pathologies such as Alzheimer’s disease are considered late-onset diseases caused by the complex combination of genetic,epigenetic,and environmental factors.There are two main types of Alzheimer’s disease,known as familial Alzheimer’s disease(onset<65 years)and late-onset or sporadic Alzheimer’s disease(onset≥65 years).Patients with familial Alzheimer’s disease inherit the disease due to rare mutations on the amyloid precursor protein(APP),presenilin 1 and 2(PSEN1 and PSEN2)genes in an autosomaldominantly fashion with closely 100%penetrance.In contrast,a different picture seems to emerge for sporadic Alzheimer’s disease,which exhibits numerous non-Mendelian anomalies suggesting an epigenetic component in its etiology.Importantly,the fundamental pathophysiological mechanisms driving Alzheimer’s disease are interfaced with epigenetic dysregulation.However,the dynamic nature of epigenetics seems to open up new avenues and hope in regenerative neurogenesis to improve brain repair in Alzheimer’s disease or following injury or stroke in humans.In recent years,there has been an increase in interest in using natural products for the treatment of neurodegenerative illnesses such as Alzheimer’s disease.Through epigenetic mechanisms,such as DNA methylation,non-coding RNAs,histone modification,and chromatin conformation regulation,natural compounds appear to exert neuroprotective effects.While we do not purport to cover every in this work,we do attempt to illustrate how various phytochemical compounds regulate the epigenetic effects of a few Alzheimer’s disease-related genes. 展开更多
关键词 Alzheimer’s disease EPIGENETICs genes METHYLATION natural products
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Response of Distribution Range Against Climate Change and Habitat Preference of Four National Protected Diploderma Species in Tibetan Plateau 被引量:1
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作者 Lin SHI Xiudong SHI +5 位作者 Yuning CAO Yayong WU Haijuan WEI Youhua CHEN Ziyan LIAO Yin QI 《Asian Herpetological Research》 SCIE CSCD 2023年第4期319-330,共12页
Understanding the spatial distribution and habitat preference for rare and endangered species are essential for effective conservation practice.We examined the spatial distribution and habitat preference of four Diplo... Understanding the spatial distribution and habitat preference for rare and endangered species are essential for effective conservation practice.We examined the spatial distribution and habitat preference of four Diploderma species(Diploderma drukdaypo,D.laeviventre,D.batangense,and D.vela),which are endemic to the Qinghai-Tibet Plateau and are currently under state protection.We used the ensembles of small models(ESM)approach and predicted potential distribution ranges of the species in current and two future climate scenarios(SSP126 and SSP585).The degree of overlap between the predicted distribution ranges and existing natural reserves was further analyzed.Habitat preference was examined using a paired quadrat method.Our results predicted that D.drukdaypo has a current distribution range of 600 km^(2),which would decrease to 50 km^(2)and 55 km^(2)under the SSP126 and SSP585 respectively.For D.laeviventre,the current distribution range is 817 km^(2),with minimum changes in the two future climate scenarios(774 km^(2)and 902 km^(2)).For D.batangense,the current distribution range is 875 km^(2),which would expand to 1522 km^(2)and 3340 km^(2)in the two future climate scenarios.Similarly for D.vela,the current distribution range is 1369 km^(2),which would change to 1825 km^(2)and 2043 km^(2)respectively under the two future climate scenarios.The effect of protection of current nature reserves are likely low for those species;we found no overlap(D.drukdaypo,D.laeviventre)or little overlap(D.batangense 2.04%–3.56%,D.vela 15.52%–16.87%)between the currently designated protection area and distribution range under current and future climate scenarios.For habitat preference,stones appear to be the critical habitat element for those species although different species had different stone requirements.Taken together,we provided critical information on potential distribution ranges and habitat preference for four endangered Diploderma species,and confirmed the inadequacy of current nature reserves.The establishment of new or expansion of existing nature reserves is urgent for the conservation of those species. 展开更多
关键词 climate change distribution range habitat preference nature reserve REPTILE
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The “Dead Universe” Theory: Natural Separation of Galaxies Driven by the Remnants of a Supermassive Dead Universe
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作者 Joel Almeida 《Natural Science》 2024年第6期65-101,共37页
This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This per... This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This perspective challenges the conventional Big Bang theory, particularly concerning dark matter, the expansion of the universe, and the interpretation of phenomena such as gravitational waves. 展开更多
关键词 Dead Universe Theory Heat Death of the Universe Big Bang Theory Universe’s Ultimate Fate Universe Expansion Big Freeze Universe Cosmological Models End of Universe Theories natural Galaxy Drift Future of the Universe Universe Cooling Down Cosmology and Entropy
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Multi-national observational study to assess quality of life and treatment preferences in patients with Crohn’s perianal fistulas
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作者 Chitra Karki Amod Athavale +10 位作者 Vijay Abilash Gary Hantsbarger Parnia Geransar Kate Lee Slobodan Milicevic Marko Perovic Leanne Raven Magdalena Sajak-Szczerba Abigail Silber Annabelle Yoon Phil Tozer 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第11期2537-2552,共16页
BACKGROUND Patients with Crohn’s disease(CD)are at risk of developing complications such as perianal fistulas.Patients with Crohn’s perianal fistulas(CPF)are affected by fecal incontinence(FI),bleeding,pain,swelling... BACKGROUND Patients with Crohn’s disease(CD)are at risk of developing complications such as perianal fistulas.Patients with Crohn’s perianal fistulas(CPF)are affected by fecal incontinence(FI),bleeding,pain,swelling,and purulent perianal discharge,and METHODS This cross-sectional observational study was conducted in patients with CD aged 21-90 years via a web-enabled questionnaire in seven countries(April-August 2021).Patients were recruited into three cohorts:Cohort 1 included patients without perianal fistulas;cohort 2 included patients with perianal fistulas without fistula-related surgery;and cohort 3 included patients with perianal fistulas and fistula-related surgery.Validated patient-reported outcome measures were used to assess quality of life.Drivers of treatment preferences were measured using a discrete choice experiment(DCE).RESULTS In total,929 patients were recruited(cohort 1,n=620;cohort 2,n=174;cohort 3,n=135).Short Inflammatory Bowel Disease Questionnaire scores were worse for patients with CPF(cohorts 2 and 3)than for those with CD without CPF(cohort 1):Mean score 3.8 and 3.7 vs 4.1,respectively,(P<0.001).Similarly,mean Revised FI and FI Quality of Life scores were worse for patients with CPF than for those with CD without CPF.Quality of Life with Anal Fistula scores were similar in patients with CPF with or without CPF-related surgery(cohorts 2 and 3):Mean score 41 and 42,respectively.In the DCE,postoperative discomfort and fistula healing rate were the most important treatment attributes influencing treatment choice:Mean relative importance 35.7 and 24.7,respectively.CONCLUSION The burden of illness in CD is significantly higher for patients with CPF and patients rate lower postoperative discomfort and higher healing rates as the most desirable treatment attributes. 展开更多
关键词 Burden of illness Crohn’s disease Discrete choice experiment Perianal fistulas Patient-reported outcomes Treatment preferences
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Tourist preferences for agricultural landscapes:a case study of terraced paddy fields in Noto Peninsula,Japan 被引量:5
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作者 CHEN Bixia QIU Zhenmian NAKAMURA Koji 《Journal of Mountain Science》 SCIE CSCD 2016年第10期1880-1892,共13页
Many agricultural landscapes have been formed through the interaction and co-evolution of nature and people, and represent the living landscapes shaped over time through intensive and continuous human cultivation. Ter... Many agricultural landscapes have been formed through the interaction and co-evolution of nature and people, and represent the living landscapes shaped over time through intensive and continuous human cultivation. Terraced paddy fields are being re-evaluated to take into account the multiple functions they fill beyond only rice cultivation, particularly their contribution to the national biodiversity strategy of Japan. Since the 1990 s, terraced paddy fields have been considered a representative cultural landscape of Japan and, at the same time, multi-stakeholder conservation activities have been conducted throughout Japan to reverse the increasing abandonment of terraces. Shiroyone Senmaida is an outstanding cultural landscape and a major tourist attraction in Noto Peninsula, Ishikawa Prefecture, which was designated through an initiative by the Food and Agriculture Organization(FAO) as a Globally Important Agricultural Heritage Systems(GIAHS) pilot site in 2011. It is important to clarify tourist preference for terraced paddy field landscapes to contribute to future policy making toward improved agricultural landscape conservation. A key finding of this study is that tourists visiting toenjoy the agricultural landscape are also concerned on the sustainability of the farming methods and preferred to maintain the naturalness of the landscape. Respondents with higher educational levels and greater concern for the biological and traditional farming knowledge aspects of the rice terraces were also more inclined to favor sustainable farming practices. Tourists preferred to maintain the naturalness and rurality of the agricultural landscape, and indicated that construction of excessive tourist facilities would cause the landscape to deteriorate. It was suggested that the local community and surroundings, including rural settlements, hills, and forests, should also be conserved together with the scenic terrace. 展开更多
关键词 Agricultural landscape Landscape aesthetics Landscape naturalness Terraced land Traditional farming Tourist preference
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Winter habitat use of snow leopards in Tomur National Nature Reserve of Xinjiang,Northwest China 被引量:1
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作者 Feng XU Ming MA +4 位作者 WeiKang YANG David BLANK YiQun WU Thomas MCCARTHY Bariusha MUNKHTSOG 《Journal of Arid Land》 SCIE 2012年第2期191-195,共5页
Snow leopards are one of the least known large cats, the population of which has dramatically de- creased. Their habitat loss was considered the main reason for the decline during the last decade, but their habitat pr... Snow leopards are one of the least known large cats, the population of which has dramatically de- creased. Their habitat loss was considered the main reason for the decline during the last decade, but their habitat preferences are still not well known. In this paper, we studied the winter habitat preferences of snow leopards in the Tomur National Nature Reserve (TNNR) in Northwest China during 2004-2005. We used sign surveys and tran- sects to study the winter habitat selection of snow leopards. The results indicated that snow leopards showed a preference for habitat variabilities in slope aspect, vegetation cover, dominant topographical features, landform ruggedness and grazing status. We found that prey availability and dominant topographical features were the most important factors that determined the winter habitat selection of snow leopards. Our results supported the idea that the habitat preferences of snow leopards are a tradeoff between suitable habitat features and avoidance of potential human interactions. 展开更多
关键词 snow leopard Panthera uncia sign survey habitat preferences Tomur National nature Reserve
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Proximity to corridors benefits bird communities in vegetated interrow vineyards in Mendoza, Argentina
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作者 Andrea Paula Goijman Agustín Zarco 《Avian Research》 SCIE CSCD 2024年第2期147-155,共9页
Management under ecological schemes and increasing habitat heterogeneity,are essential for enhancing biodiversity in vineyards.Birds provide several contributions to agriculture,for example pest control,recreation and... Management under ecological schemes and increasing habitat heterogeneity,are essential for enhancing biodiversity in vineyards.Birds provide several contributions to agriculture,for example pest control,recreation and enhancing human mental health,and have intrinsic value.Birds are also ideal model organisms because they are easy to survey,and species respond differently to agricultural land use at different scales.Vegetated borders of crops are key for many species of birds,and distance to the border have been found to be an important factor in vineyard-dominated agroecosystems.We evaluate if there are differences in the bird assemblage,between the interior compared to borders within vineyards,using a hierarchical community occupancy model.We hypoth-esized that occupancy of birds is greater in environments with greater heterogeneity,which in this study was considered to be contributed by the proximity to vegetated corridors.We expected that vineyard borders close to corridors will have higher bird occupancy than the center of the vineyard.The research was conducted in three vineyards with biodiversity-friendly management practices,in Gualtallary,Mendoza,Argentina.Bird surveys were conducted over three breeding seasons from 2018 to 2020.Occupancy and richness of the bird community was more closely associated with the borders adjacent to the corridors than with the interior of the vineyards,as we initially predicted,although the assemblage of birds did not differ much.More than 75%of the registered species consume exclusively or partially invertebrates.Biodiversity-friendly management and ecological schemes,together with vegetated corridors provide multiple benefits for biodiversity conservation.These ap-proaches not only minimize the use of agrochemicals but also prioritize soil cover with spontaneous vegetation,which supports a diverse community of insectivorous bird species,potentially contributing to pest control. 展开更多
关键词 Avian Bayesian analysis Field scale agroecosystem Management Multi-species occupancy model natures contributions to people
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PREFERENCE AND EVOLUTION IN THE ITERATED PRISONER'S DILEMMA
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作者 王先甲 刘伟兵 《Acta Mathematica Scientia》 SCIE CSCD 2009年第2期456-464,共9页
Game theory is extensively used to study strategy-making and actions of play- ers. The authors proposed an analysis method for study the evolutionary outcome and behaviors of players with preference in iterated priso... Game theory is extensively used to study strategy-making and actions of play- ers. The authors proposed an analysis method for study the evolutionary outcome and behaviors of players with preference in iterated prisoner's dilemma. In this article, a preference parameter k was introduced in the payoff matrix, wherein the value of k denotes the player's degree of egoism and altruism (preference). Then, a game-theoretic dynamical model was formulated using Birth-and-Death process. The authors studied how preference influences the evolutionary equilibrium and behaviors of players. The authors get the general results: egoism leads to defection, and altruism can make players build trust and maintain cooperation, and so, the hope of the Pareto optimal solution. In the end, the simulation experiments proved the efficiency of the method. 展开更多
关键词 Game theory evolutionary game prisoner's dilemma Birth-and-Death process preference
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Do inflammatory bowel disease patient preferences from treatment outcomes differ by ethnicity and gender?A cross-sectional observational study
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作者 Timna Naftali Vered Richter +3 位作者 Amir Mari Tawfik Khoury Haim Shirin Efrat Broide 《World Journal of Clinical Cases》 SCIE 2022年第35期12899-12908,共10页
BACKGROUND Inflammatory bowel disease(IBD)patients’expectations of treatment outcomes may differ by ethnicity.AIM To investigate treatment preferences of Jewish and Arabs patients.METHODS This prospective survey rank... BACKGROUND Inflammatory bowel disease(IBD)patients’expectations of treatment outcomes may differ by ethnicity.AIM To investigate treatment preferences of Jewish and Arabs patients.METHODS This prospective survey ranked outcomes treatment preferences among Arab IBD patients,based on the 10 IBD-disk items compared to historical data of Jews.An anonymous questionnaire in either Arabic or Hebrew was distributed among IBD patients.Patients were required to rank 10 statements describing different aspects of IBD according to their importance to the patients as treatment goals.Answers were compared to the answers of a historical group of Jewish patients.RESULTS IBD-disk items of 121 Arabs were compared to 240 Jewish patients.The Jewish patients included more females,[151(62.9%)vs 52(43.3%);P<0.001],higher education level(P=0.02),more urban residence[188(78.3%)vs 54(45.4%);P<0.001],less unemployment[52(21.7%)vs 41(33.9%);P=0.012],higher income level(P<0.001),and more in a partnership[162(67.8%)vs 55(45.4%);P<0.001].Expectations regarding disease symptoms:abdominal pain,energy,and regular defecation ranked highest for both groups.Arabs gave significantly lower rankings(range 4.29-6.69)than Jewish patients(range 6.25-9.03)regarding all items,except for body image.Compared to Arab women,Jewish women attached higher priority to abdominal pain,energy,education/work,sleep,and joint pain.Multivariable regression analysis revealed that higher patient preferences were associated with Jewish ethnicity(OR 4.77;95%CI 2.36-9.61,P<0.001)and disease activity.The more active the disease,the greater the odds ratio for higher ranking of the questionnaire items(1-2 attacks per year:OR 2.13;95%CI 1.02-4.45,P=0.043;and primarily active disease:OR 5.29;95%CI 2.30-12.18,P<0.001).Factors inversely associated with higher patient preference were male gender(OR 0.5;95%CI 0.271-0.935,P=0.030),UC(OR 0.444;95%CI 0.241-0.819,P=0.009),and above average income level(OR 0.267;95%CI:0.124-0.577,P=0.001).CONCLUSION The highest priority for treatment outcomes was symptom relief.,Patients preferences were impacted by ethnicity,gender,and socio-economic disparity.Understanding patients'priorities may improve communication and enable a personalized approach. 展开更多
关键词 Inflammatory bowel disease Crohn’s disease Ulcerative colitis Patientspreferences ETHNICITY IBD-disk Patients reported outcomes
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NATURE'S STOREHOUSE——SICHUAN PROVINCE
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《China's Foreign Trade》 1996年第10期12-,6,共2页
Sichuan province,called"Chuan"or"Shu"for short,lies on the upperreaches of the Yangtze River.It is in a subtropical zone and coversan area of 570,000 sq km,making it the fifth biggest in the countr... Sichuan province,called"Chuan"or"Shu"for short,lies on the upperreaches of the Yangtze River.It is in a subtropical zone and coversan area of 570,000 sq km,making it the fifth biggest in the country.Its population of 120 million is the largest in China.There are 13prefectures,seven prefecture-level districts and three autonomousprefecture of ethnic minority groups in the province,with 219counties and county-level cities and districts.Its provincial capital isChengdu. 展开更多
关键词 OVER sICHUAN PROVINCE natures sTOREHOUsE THAN
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Application Research of Ingroup Preference in Employee Relationship Management
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作者 Lijuan WAN Yawen WANG 《Asian Agricultural Research》 2017年第5期5-9,共5页
With stepwise development of Chinese enterprise,management problem is increasingly prominent,especially human resource management issues. Facing international environment of entering into World Trade Organization,the ... With stepwise development of Chinese enterprise,management problem is increasingly prominent,especially human resource management issues. Facing international environment of entering into World Trade Organization,the country accelerates construction pace of human resource management subject in colleges and universities,which provides professional channel for management efficiency and market competition ability of Chinese enterprise,but it is still far from practice. In this paper,the concept,origin and inhibition factors of ingroup preference are elaborated. Based on the visual angle of ingroup preference,started from four dimensions( enterprise incentive system,talent management idea,psychological contract and employee communication consciousness),main problems existing in employee relationship management of modern enterprise are explored. It is specially emphasized that manager often holds the blame in front of dealing with the crisis after contradiction,which is " fatal point" neglected in employee relationship management of modern enterprise. To improve its core competitive power,enterprise must value harmonious relationship with employees. 展开更多
关键词 Employee relationship management Ingroup preference Insecurity sense Enterprise’s core competitive power
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Hilbert’s Fourth Problem: Searching for Harmonic Hyperbolic Worlds of Nature
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作者 A. P. Stakhov 《Journal of Applied Mathematics and Physics》 2013年第3期60-66,共7页
Recently the new unique classes of hyperbolic functions-hyperbolic Fibonacci functions based on the “golden ratio”, and hyperbolic Fibonacci l-functions based on the “metallic proportions” (l is a given natural nu... Recently the new unique classes of hyperbolic functions-hyperbolic Fibonacci functions based on the “golden ratio”, and hyperbolic Fibonacci l-functions based on the “metallic proportions” (l is a given natural number), were introduced in mathematics. The principal distinction of the new classes of hyperbolic functions from the classic hyperbolic functions consists in the fact that they have recursive properties like the Fibonacci numbers (or Fibonacci l-numbers), which are “discrete” analogs of these hyperbolic functions. In the classic hyperbolic functions, such relationship with integer numerical sequences does not exist. This unique property of the new hyperbolic functions has been confirmed recently by the new geometric theory of phyllotaxis, created by the Ukrainian researcherOleg Bodnar(“Bodnar’s hyperbolic geometry). These new hyperbolic functions underlie the original solution of Hilbert’s Fourth Problem (Alexey Stakhov and Samuil Aranson). These fundamental scientific results are overturning our views on hyperbolic geometry, extending fields of its applications (“Bodnar’s hyperbolic geometry”) and putting forward the challenge for theoretical natural sciences to search harmonic hyperbolic worlds of Nature. The goal of the present article is to show the uniqueness of these scientific results and their vital importance for theoretical natural sciences and extend the circle of readers. Another objective is to show a deep connection of the new results in hyperbolic geometry with the “harmonic ideas” of Pythagoras, Plato and Euclid. 展开更多
关键词 HYPERBOLIC GEOMETRY of Lobachevski HYPERBOLIC Fibonacci Functions Bodnar’s GEOMETRY of Phyllotaxis Hilbert’s FOURTH PROBLEM New HYPERBOLIC WORLDs of nature
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Hengshui Lake China’s Key Wetland Nature Reserve
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《China Today》 2002年第10期53-53,共1页
WETLAND, an important eco-logical sys-tem, is of inestimable scientific, ecological, social and economic value. Bestowed liberally with nature’s bounty, China boasts various types of wetland, and during the past year... WETLAND, an important eco-logical sys-tem, is of inestimable scientific, ecological, social and economic value. Bestowed liberally with nature’s bounty, China boasts various types of wetland, and during the past years has built over 130 wetland nature reserves, of which ten percent are 展开更多
关键词 nature s Key Wetland nature Reserve Hengshui Lake China
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Digital Disparities:How Artificial Intelligence Can Facilitate Anti-Black Racism in the U.S.Healthcare Sector
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作者 Anthony Victor Onwuegbuzia 《International Relations and Diplomacy》 2024年第1期40-50,共11页
This paper delves into the intricate interplay between artificial intelligence(AI)systems and the perpetuation of Anti-Black racism within the United States medical industry.Despite the promising potential of AI to en... This paper delves into the intricate interplay between artificial intelligence(AI)systems and the perpetuation of Anti-Black racism within the United States medical industry.Despite the promising potential of AI to enhance healthcare outcomes and reduce disparities,there is a growing concern that these technologies may inadvertently/advertently exacerbate existing racial inequalities.Focusing specifically on the experiences of Black patients,this research investigates how the following AI components:medical algorithms,machine learning,and natural learning processes are contributing to the unequal distribution of medical resources,diagnosis,and health care treatment of those classified as Black.Furthermore,this review employs a multidisciplinary approach,combining insights from computer science,medical ethics,and social justice theory to analyze the mechanisms through which AI systems may encode and reinforce racial biases.By dissecting the three primary components of AI,this paper aims to present a clear understanding of how these technologies work,how they intersect,and how they may inherently perpetuate harmful stereotypes resulting in negligent outcomes for Black patients.Furthermore,this paper explores the ethical implications of deploying AI in healthcare settings and calls for increased transparency,accountability,and diversity in the development and implementation of these technologies.Finally,it is important that I prefer the following paper with a clear and concise definition of what I refer to as Anti-Black racism throughout the text.Therefore,I assert the following:Anti-Black racism refers to prejudice,discrimination,or antagonism directed against individuals or communities of African descent based on their race.It involves the belief in the inherent superiority of one race over another and the systemic and institutional practices that perpetuate inequality and disadvantage for Black people.Furthermore,I proclaim that this form of racism can be manifested in various ways,such as unequal access to opportunities,resources,education,employment,and fair treatment within social,economic,and political systems.It is also pertinent to acknowledge that Anti-Black racism is deeply rooted in historical and societal structures throughout the U.S.borders and beyond,leading to systemic disadvantages and disparities that impact the well-being and life chances of Black individuals and communities.Addressing Anti-Black racism involves recognizing and challenging both individual attitudes and systemic structures that contribute to discrimination and inequality.Efforts to combat Anti-Black racism include promoting awareness,education,advocacy for policy changes,and fostering a culture of inclusivity and equality. 展开更多
关键词 Bias in algorithms Racial disparities in U.s.healthcare Discriminatory healthcare practices Black patient outcomes Automated decision-making and racism Machine Learning natural language processing
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China's Nature Reserves
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《China Today》 1997年第11期42-43,共2页
关键词 nature China’s nature Reserves
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The foundation of the theory of the universe dark energy and its nature
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作者 Murad Shibli 《Natural Science》 2011年第3期165-185,共21页
Surprisingly recent astronomical observations have provided strong evidence that our universe is not only expanding, but also is expanding at an accelerating rate. This paper pre- sents a basis of the theory of univer... Surprisingly recent astronomical observations have provided strong evidence that our universe is not only expanding, but also is expanding at an accelerating rate. This paper pre- sents a basis of the theory of universe space- time dark energy, a solution of Einstein’s cosmological constant problem, physical interpretation of universe dark energy and Einstein’s cosmological constant Lambda and its value ( = 0.29447 × 10-52 m-2), values of universe dark energy density 1.2622 × 10-26 kg/m3 = 6.8023 GeV, universe critical density 1.8069 × 10-26 kg/m3 = 9.7378 GeV, universe matter density 0.54207 × 10-26 kg/m3 = 2.9213 GeV, and universe radiation density 2.7103 × 10-31 kg/m3 = 1.455 MeV. The interpretation in this paper is based on geometric modeling of space-time as a perfect four- dimensional continuum cosmic fluid and the momentum generated by the time. In this modeling time is considered as a mechanical variable along with other variables and treated on an equal footing. In such a modeling, time is considered to have a mechanical nature so that the momentum associated with it is equal to the negative of the universe total energy. Since the momentum associated with the time as a mechanical variable is equal to the negative system total energy, the coupling in the time and its momentum leads to maximum increase in the space-time field with 70.7% of the total energy. Moreover, a null paraboloid is obtained and interpreted as a function of the momentum generated by time. This paper presents also an interpretation of space-time tri-dipoles, gravity field waves, and gravity carriers (the gravitons). This model suggests that the space-time has a polarity and is composed of dipoles which are responsible for forming the orbits and storing the space-time energy-momentum. The tri-di- poles can be unified into a solo space-time dipole with an angle of 45 degrees. Such a result shows that the space-time is not void, on the contrary, it is full of conserved and dynamic energy-momentum structure. Furthermore, the gravity field waves is modeled and assumed to be carried by the gravitons which move in the speed of light. The equivalent mass of the graviton (rest mass) is found to be equal to 0.707 of the equivalent mass of the light photons. Such a result indicates that the lightest particle (up to the author’s knowledge) in the nature is the graviton and has an equivalent mass equals to 2.5119 x 10-52 kg. Based on the fluidic nature of dark energy, a fourth law of thermodynamics is proposed and a new physical interpretation of Kepler’s Laws are presented. Additionally, based on the fact that what we are observing is just the history of our universe, on the Big Bang Theory, Einstein’s General Relativity, Hubble Parameter, cosmic inflation theory and on NASA’s observation of supernova 1a, then a second-order (parabolic) parametric model is obtained in this proposed paper to describe the accelerated ex- pansion of the universe. This model shows that the universe is approaching the universe cosmic horizon line and will pass through a critical point that will influence significantly its fate. Considering the breaking symmetry model and the variational principle of mechanics, then the universe will witness an infinitesimally stationary state and a symmetry breaking. As result of that, our universe will experience in the near future, a very massive impulse force in the order 1083 N. Subsequently, the universe will collapse. Finally, simulation results are demonstrated to verify the analytical results. 展开更多
关键词 DARK ENERGY nature of DARK ENERGY Expansion of The UNIVERsE Einstein’s Cosmological Constant UNIVERsE Mass/Energy Densities space-Time DIPOLEs GRAVITONs Fourth Law of Thermodynamics Fate of the UNIVERsE Kelper’s Laws
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Whole Perfect Vectors and Fermat’s Last Theorem
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作者 Ramon Carbó-Dorca 《Journal of Applied Mathematics and Physics》 2024年第1期34-42,共9页
A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm de... A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm definition, and some vector-specific structures. 展开更多
关键词 Fermat’s Last Theorem Whole Perfect Vectors sine and Cosine Functions natural and Rational Vectors Fermat Vectors
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Nature and Love——A Reflection on the Exhibitions of Li Zijian's Oil Paintings
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作者 Jiu Erh 《China & The World Cultural Exchange》 2001年第3期16-17,共2页
关键词 LI nature and Love A Reflection on the Exhibitions of Li Zijian’s Oil Paintings
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Using Nature’s Gift
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作者 Geoffrey Kamadi 《ChinAfrica》 2013年第4期36-36,共1页
Kenya gets affordable solar-powered lighting and mobile phone charging
关键词 nature PHONE Using natures Gift
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Using Nature’s Bounty
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作者 Mohamed Abdel-Monem Tian Ping 《ChinAfrica》 2013年第3期26-26,共1页
THE Maasai people are probably among the most well-known ethnic groups in East Africa for their reputations as brave warriors. But they have been plagued with a major problem for several generations: limited access t... THE Maasai people are probably among the most well-known ethnic groups in East Africa for their reputations as brave warriors. But they have been plagued with a major problem for several generations: limited access to water. "Once you mention water, clean or unclean, what comes to my mind is long distance' said an elder leader in a Maasai village in Kenya. "We spend so much time looking for water for our animals and for our own consumption that we have no strength left for anything else." It is true that the women and children in Maasai communities hardly have time for anything else after the trek to fetch water, which usually takes them 8 hours each day. 展开更多
关键词 nature Using natures Bounty
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