bluuebunny/crossref_metadata_2025 huggingface dataset:
Diseño de prototipo para prótesis manufacturada con tecnología 3d en amputación transtibial
Authors: Veloz Pastrano Ronald Steven , Morales Fernández Estefany Michelle
Published: August 2024

Se recapitula en este segmento como la tecnología 3D ha revolucionado el ámbito de salud, y como hace algunas décadas en el pasado, resultaba una limitación el tener una prótesis para regresar a las labores cotidianas Así mismo se estableció un alcance explicativo porque proporcionó información que aporta a realizar de manera detallada paso a paso la elaboración de medidas previo del diseño de la prótesis. En cuanto a la instrumentación aplicada está el test de Daniel, el cual se encarga de evaluar la fuerza muscular en personas con amputación, además de valoraciones antropométricas del muñón, y por último se basó el diseño en un programa denominado Autodesk Fusion 360 el cual se encarga del delineación y mapeo de la prótesis. Basando su ergonomía y el tipo de material en función de los parámetros analizados como el nivel de vida y el peso del enfermo interesado en la prótesis, concluyendo de esta manera que la acción preventiva de evaluar a un paciente es clave al momento de saber si es un candidato potencial a prótesis o no con tecnología 3D.
Sintomatología musculoesquelética en columna y miembro superior asociado a posturas forzadas
Authors: Collaguazo Troya Estefanía , Cevallos Egas Cristian Daniel
Published: August 2024

El personal administrativo y docente, por sus actividades laborales se predisponen a la aparición de sintomatologías musculoesqueléticas, especialmente en miembro superior y columna. Objetivo: determinar la prevalencia de sintomatología musculoesquelética de columna y miembro superior por posturas forzadas en el personal administrativo y docente del Itecsur con el fin de proponer medidas correctivas. Método: estudio no experimental de cohorte transversal en el cual intervinieron seis trabajadores del personal administrativo y 10 docentes, seleccionados mediante un muestreo no probabilístico intencional. Resultados: en el personal administrativo la sintomatología de cuello y muñeca predominó, en el género masculino y en el género femenino en los últimos siete días la sintomatología fue de hombro, cuello y muñeca (60%), y en el último año cuello y muñeca (100%). En el personal docente en el género masculino el predominio fue de hombro codo y muñeca, mientras que en el género femenino en los últimos siete días fue la sintomatología dorsolumbar (56%), en último año cuello y dorsolumbar (78%), el género femenino presentó un riesgo alto en el lado derecho el mismo que necesitaría de pronta acción y el personal administrativo de género masculino y femenino obtuvo un riesgo medio en los dos hemicuerpos. Conclusiones: La mayor prevalencia de sintomatología musculoesquelética en el personal docente y administrativo fue en el género femenino durante el último año y los segmentos involucrados son: cuello, hombro, muñeca y mano, los docentes presentan un riesgo alto a diferencia del personal administrativo
Derechos de las personas con discapacidad en el Ecuador y su aplicación práctica
Authors: Añarumba Nolasco Emily Belén , Guevara Zambrano Ana Belén , Vivanco Guzmán Ana Beatriz
Published: August 2024

El presente artículo aborda la importancia de los derechos de las personas con discapacidad en Ecuador, destacando la necesidad de promover la inclusión y la igualdad, se propone analizar de forma integral la estructura y aplicación de estos derechos. En el cual se analizó las normativas en el área de educación, atención, médica, empleo y participación comunitaria con el fin de identificar las brechas en la implementación de políticas inclusivas y proponer soluciones. La metodología empleada fue el enfoque histórico - jurídico para el conocimiento jurídico, la comparación jurídica permitió comparar la normativa ecuatoriana con los estándares internacionales y buenas prácticas en derechos de discapacidad, el país tiene un marco normativo sólido, pero la inclusión total requiere un enfoque diversificado y la aplicación efectiva de políticas públicas.
MANEJO NUTRICIONAL DA RESISTÊNCIA À INSULINA NA SÍNDROME DE OVÁRIO POLICÍSTICO
Authors: Araújo Bruna Oliveira , Amorim Flávia Caroline Ferreira , Ataides Iana Flor Tovar , Silva Kefferson Rogério Faustino , Pereira Lavínia Maria Aquino , Sobrinho Marcelo Luíz Cabral de Souza , Bastos Naiara Almeida de Oliveira , Lima Naiadhe Carvalho , Rosa Natalia de Oliveira Santa , Lima Maria Eduarda Veloso , Souza Rodolfo Tanaka Lucena de Freitas , Carmo Simone Gonzaga do
Published: August 2024

Introduction: Polycystic Ovary Syndrome (PCOS) is the most common hormonal disorder among women during the ovulation and menstrual periods. Its origin is still unknown; however, the treatment of the disease involves changes in dietary habits and physical activity practices. Reducing carbohydrate intake has positive effects on PCOS, as this low carbohydrate consumption allows for depletion of muscle and hepatic glycogen stores. Objective: To evaluate the nutritional management of insulin resistance in PCOS. Materials and Methods: Literature reviews were conducted focusing on the last cinco years, using the PubMed, Scielo, and Virtual Health Library (BVS) databases. Result: A hypocaloric diet showed improvements in metabolic rates, menstrual cycle, weight loss, and insulin resistance parameters. Conclusion: Although there is no specific diet for women with insulin resistance and polycystic ovary syndrome, the results of studies have shown that low-calorie diets in conjunction with physical activity can influence the reduction of anthropometric measurements of patients, and therefore assist in the treatment of PCOS and insulin resistance.
ANÁLISE CIENTÍFICA DOS IMPACTOS E ESTRATÉGIAS DE PREVENÇÃO DE INCÊNDIOS URBANOS
Authors: Barcellos Rogério Quinteiro
Published: August 2024

Urban fires pose a significant threat to public safety and the urban environment. In view  of this, a bibliographical research was carried out with the objective of examining the  main factors that contribute to the occurrence of fires in urban areas, such as population  density, inadequate land use, infrastructure and construction standards, climatic  conditions, prevention and response systems of fires, as well as human behavior and  public education. The impacts of urban fires were also researched, namely environmental  impacts, social and economic impacts and impacts on critical infrastructures. International Journals publish discussions by relevant Authors about urban fire prevention  and mitigation strategies, which leads to the analysis of emergency responses and  management and leads to reflection on post-fire recovery and resilient reconstruction.  This analysis highlights the importance of integrated approaches to minimize urban fire  risks and protect vulnerable communities.
A Study of Impact on Financial Performance of Top listed Indian Companies with Reference to Emission of Carbon and Harmful Gases related CSR Disclosure Practices
Authors: Navani Heena , Bhatt Aashal
Published: August 2024

Corporate Social Responsibility (CSR) as a notion has been the focal point of various considerations and much research over the past few years; and has occupied a significant role in the academic and business area. Evolving all the time, it has deformed from a purely charitable to a structural and finally tactical activity. For an organization to be victorious, creating earnings is the main aim but at the same time it conveys the consciousness of being socially responsible. India is the first country to have legislated CSR mandates. It is very probable that the new legislation will be a game-changer, inspiring new investments, judicious attempts and responsibility in the way CSR is being formed and survived in India. CSR Disclosures are basically categorized into Mandatory and Voluntary practices of disclosure. Firm’s performance and reputation are linked with Voluntary disclosure patterns. Various categories like Environment, Human resource, Community involvement, Energy etc. affect CSR Disclosure which in turn affects the financial performance of the firm which is relevant for the stakeholders of the firm. This paper makes a humble attempt to study the various corporate characteristics like size and age of the company, sectorial influence and ownership concentration on emission of carbon and harmful gases. It also attempts to study the CSR disclosure score of the company, which in turn affects the financial performance of the company measured by ROA, ROE and Tobins Q of the Company.
Integration of Cutting-Edge Technologies such as Internet of Things (IoT) and 5G in Health Monitoring Systems: A Comprehensive Legal Analysis and Futuristic Outcomes
Authors: Singh Bhupinder , Kaunert Christian
Published: August 2024

The convergence of cutting-edge technologies such as the Internet of Things (IoT) and 5G has given rise to innovative applications in various sectors, notably in healthcare. The integration of cutting-edge technologies, notably the Internet of Things (IoT) and 5G, into health monitoring systems has brought forth a transformative paradigm in healthcare. This comprehensive legal analysis explores the intricate intersection of these technologies and the legal landscape governing their application in health monitoring. Delving into the realms of ethics, regulation, and privacy, this study examines the multifaceted challenges and opportunities that arise from this convergence. By scrutinizing patient data protection, medical device regulations, and liability concerns, the analysis offers insights into crafting effective legal frameworks. Additionally, it contemplates the futuristic outcomes of these advancements, considering the potential for enhanced patient care, remote monitoring, and seamless healthcare delivery. This study envisions a harmonious integration of technology and law that not only ensures the rights and privacy of patients but also paves the way for an innovative and patient-centric healthcare future. This research paper critically examines the integration of IoT and 5G technologies in health monitoring systems and analyzes the legal implications arising from their deployment. With a focus on the ethical, regulatory, and privacy concerns associated with these technologies, the paper aims to provide a comprehensive legal analysis that addresses the challenges and opportunities presented by their integration in the healthcare domain.
Adapting Digital Libraries Open Source Software to Meet the Users’ Needs: the case of the University Algiers 1 Central Library
Authors: Touil Asma , Nadir Ghanem
Published: August 2024

Open source software have been able to impose themselves in all areas in a short period of time thanks to their particular characteristics. The field of libraries has not escaped from the modern technical orientations. A great number of world libraries have invested in these software to activate and develop their services. The Algerian university libraries have chosen the way towards the use of these software in shade of the shortage of their budget and the possibility of benefitting from these software free of charge on the Internet with the availability of their source code and the possibility for amending them in line with the needs of these libraries. One of these important experiments is certainly that of the University Benyoucef Benkhadda – Algiers 1- Central Library in using Dspace system. Throughout our study, we will highlight this experiment via the identification of, on the one hand, the degree of its benefit from the means provided by this software, and, on the other hand, the power of the library in adapting it, so that new services can be developed for responding to some of the users’ needs.
Home hemodialysis
Authors: Tomar Özdem Kavraz
Published: August 2024

Chronic kidney disease (CKD) is a public health problem with increasing prevalence worldwide and is associated with significant morbidity and mortality . According to 2022 data, there are a total of 13725 patients receiving renal replacement therapy (RRT) for end-stage renal disease (ESRD) in Turkey. Hemodialysis (HD) accounts for a large proportion of patients receiving RRT with 10287 patients . Although kidney transplantation is the best treatment option for patients with ESRD, the majority of patients do not have access to this treatment for various reasons. Most patients are treated with HD and peritoneal dialysis (PD), which are traditional methods of RRT. HD has two modalities: conventional HD and home hemodialysis (HHD).
Study of the Role of Oxidative Stress in Pathophysiology of Cardiovascular Diseases
Authors: Derouiche Samir , Guemari Imane Yousra , Boulaares Islam
Published: August 2024

Cardiovascular system is primarily considered as the human body's transport system. The cardiovascular system keeps life pumping through the body. Understanding the functions of the cardiovascular system, along with its various pathways of veins, arteries and capillaries, is essential in the provision of safe and effective care. Cardiovascular disease (CVD) remains to be the leading cause of premature deaths across the globe. Cardiovascular disease is an umbrella term for a number of linked pathologies. Cardiovascular diseases (CVD) are complex entities with heterogeneous pathophysiologic mechanisms and increased oxidative stress has been viewed as one of the potential common etiologies in various CVD. Oxidative stress in cardiovascular system may produce various cardiovascular diseases such as atherosclerosis, ischemic heart disease, and hypertension. In conclusion, oxidative stress is a condition that accompanies diseases of the cardiovascular system, and it may be responsible for the development of the disease or its complications, which must be taken into account in any treatment system.
Ingeniería de menús basada en costos de producción, una herramienta para la rentabilidad de los restaurantes
Authors: Espín Oleas Gabriela  Alejandra , Galarza Iván , Guevara-Aroca Francisco Xavier
Published: August 2024

Un reto en la gestión de restaurantes es evaluar y establecer costos de producción a los servicios. Se aplicó un diseño metodológico con enfoque mixto, en el enfoque cualitativo se usó la revisión de fuentes bibliográficas relacionadas con costos de servicios y la aplicación de una entrevista semiestructurada a dos administradores de restaurantes.
Para el enfoque cuantitativo se aplicó el método de ingeniería de menús basado en la literatura de Kasavana, Smith (1990), la técnica del Boston Consulting Group BCG y recomendaciones sobre reingeniería del menú de (Noone & Cachia, 2020) Los resultados reflejan que existen diferencias al aplicar estas dos metodologías.
Este trabajo tiene implicaciones teóricas y prácticas; contribuye a orientar a cómo establecer costos de producción en el sector restaurantes e invita a académicos y profesionales del sector a realizar el análisis del menú basado en costos de producción y no solo en costos de materias.
A MSTNDel273C mutation with FGF5 knockout sheep by CRISPR/Cas9 promotes skeletal muscle myofiber hyperplasia
Authors: Chen Ming-Ming , Zhao Yue , Xu Xue-Ling , Zhang Xiao-Sheng , Zhang Jin-Long , Wu Su-Jun , Liu Zhi-Mei , Yuan Yi-Ming , Guo Xiao-Fei , Qi Shi-Yu , Yi Guang , Wang Shu-Qi , Li Huang-Xiang , Wu Ao-Wu , Liu Guo-Shi , Yu Kun , Deng Shoulong , Han Hong-Bing , Lv Feng-Hua , Li Yan , Lian Zheng-Xing
Published: August 2024

Mutations in the well-known Myostatin (
MSTN
) produce a “double-muscle” phenotype, which makes it commercially invaluable for improving livestock meat production and providing high-quality protein for humans. However, mutations at different loci of the
MSTN
often produce a variety of different phenotypes. In the current study, we increased the delivery ratio of Cas9 mRNA to sgRNA from the traditional 1:2 to 1:10, which improves the efficiency of the homozygous mutation of biallelic gene. Here, a
MSTN
Del273C
mutation with
FGF5
knockout sheep, in which the
MSTN
and
FGF5
dual-gene biallelic homozygous mutations were produced via the deletion of 3-base pairs of AGC in the third exon of
MSTN
, resulting in cysteine-depleted at amino acid position 273, and the
FGF5
double allele mutation led to inactivation of
FGF5
gene. The
MSTN
Del273C
mutation with
FGF5
knockout sheep highlights a dominant “double-muscle” phenotype, which can be stably inherited. Both F0 and F1 generation mutants highlight the excellent trait of high-yield meat with a smaller cross-sectional area and higher number of muscle fibers per unit area. Mechanistically, the
MSTN
Del273C
mutation with
FGF5
knockout mediated the activation of
FOSL1
via the MEK-ERK-FOSL1 axis. The activated
FOSL1
promotes skeletal muscle satellite cell proliferation and inhibits myogenic differentiation by inhibiting the expression of MyoD1, and resulting in smaller myotubes. In addition, activated ERK1/2 may inhibit the secondary fusion of myotubes by Ca
2+
-dependent CaMKII activation pathway, leading to myoblasts fusion to form smaller myotubes.
Increasing adult neurogenesis protects mice from epilepsy
Authors: Jain Swati , LaFrancois John J , Gerencer Kasey , Botterill Justin J , Kennedy Meghan , Criscuolo Chiara , Scharfman Helen E
Published: August 2024

Neurogenesis occurs in the adult brain in the hippocampal dentate gyrus, an area that contains neurons which are vulnerable to insults and injury, such as severe seizures. Previous studies showed that increasing adult neurogenesis reduced neuronal damage after these seizures. Because the damage typically is followed by chronic life-long seizures (epilepsy), we asked if increasing adult neurogenesis would prevent epilepsy. Adult neurogenesis was selectively increased by deleting the pro-apoptotic gene
Bax
from Nestin-expressing progenitors. Tamoxifen was administered at 6 weeks of age to conditionally delete
Bax
in Nestin-CreER
T2
Bax
fl/fl
mice. Six weeks after tamoxifen administration, severe seizures (status epilepticus; SE) were induced by injection of the convulsant pilocarpine. After mice developed epilepsy, seizure frequency was quantified for 3 weeks. Mice with increased adult neurogenesis exhibited fewer chronic seizures. Postictal depression was reduced also. These results were primarily in female mice, possibly because they were the more affected by
Bax
deletion than males, consistent with sex differences in
Bax
. The female mice with enhanced adult neurogenesis also showed less neuronal loss of hilar mossy cells and hilar somatostatin-expressing neurons than wild type females or males, which is notable because these two hilar cell types are implicated in epileptogenesis. The results suggest that selective
Bax
deletion to increase adult neurogenesis can reduce experimental epilepsy, and the effect shows a striking sex difference. The results are surprising in light of past studies showing that suppressing adult-born neurons can also reduce chronic seizures.
Discovery of the 1-naphthylamine biodegradation pathway reveals a broad-substrate-spectrum enzyme catalyzing 1-naphthylamine glutamylation
Authors: Zhang Shu-Ting , Deng Shi-Kai , Li Tao , Maloney Megan E , Li De-Feng , Spain Jim C , Zhou Ning-Yi
Published: August 2024

1-Naphthylamine (1NA), which is harmful to human and aquatic animals, has been used widely in the manufacturing of dyes, pesticides, and rubber antioxidants. Nevertheless, little is known about its environmental behavior and no bacteria have been reported to use it as the growth substrate. Herein, we describe a pathway for 1NA degradation in the isolate Pseudomonas sp. strain JS3066, determine the structure and mechanism of the enzyme NpaA1 that catalyzes the initial reaction, and reveal how the pathway evolved. From genetic and enzymatic analysis, a five gene-cluster encoding a dioxygenase system was determined to be responsible for the initial steps in 1NA degradation through glutamylation of 1NA. The γ-glutamylated 1NA was subsequently oxidized to 1,2-dihydroxynaphthalene which was further degraded by the well-established pathway of naphthalene degradation via catechol. A glutamine synthetase-like (GS-like) enzyme (NpaA1) initiates 1NA glutamylation, and this enzyme exhibits a broad substrate selectivity toward a variety of anilines and naphthylamine derivatives. Structural analysis revealed that the aromatic residues in the 1NA entry tunnel and the V201 site in the large substrate-binding pocket significantly influence NpaA1’s substrate preferences. The findings enhance understanding of degrading polycyclic aromatic amines, and will also enable the application of bioremediation at naphthylamine contaminated sites.
Released bacterial ATP shapes local and systemic inflammation during abdominal sepsis
Authors: Spari Daniel , Schmid Annina , Sanchez-Taltavull Daniel , Murugan Shaira , Keller Keely , Ennaciri Nadia , Salm Lilian , Stroka Deborah , Beldi Guido
Published: August 2024

Sepsis causes millions of deaths per year worldwide and is a current global health priority declared by the WHO. Sepsis-related deaths are a result of dysregulated inflammatory immune responses indicating the need to develop strategies to target inflammation. An important mediator of inflammation is extracellular adenosine triphosphate (ATP) that is released by inflamed host cells and tissues, and also by bacteria in a strain-specific and growth-dependent manner. Here, we investigated the mechanisms by which bacteria release ATP. Using genetic mutant strains of Escherichia coli (E. coli), we demonstrate that ATP release is dependent on ATP synthase within the inner bacterial membrane. In addition, impaired integrity of the outer bacterial membrane notably contributes to ATP release and is associated with bacterial death. In a mouse model of abdominal sepsis, local effects of bacterial ATP were analyzed using a transformed E. coli bearing an arabinose-inducible periplasmic apyrase hydrolyzing ATP to be released. Abrogating bacterial ATP release shows that bacterial ATP suppresses local immune responses, resulting in reduced neutrophil counts and impaired survival. In addition, bacterial ATP has systemic effects via its transport in outer membrane vesicles (OMV). ATP-loaded OMV are quickly distributed throughout the body and upregulated expression of genes activating degranulation in neutrophils, potentially contributing to the exacerbation of sepsis severity. This study reveals mechanisms of bacterial ATP release and its local and systemic roles in sepsis pathogenesis.
Nuclear Translocation of SIRT4 Mediates Deacetylation of U2AF2 to Modulate Renal Fibrosis Through Alternative Splicing-mediated Upregulation of CCN2
Authors: Yang Guangyan , Xiang Jiaqing , Yang Xiaoxiao , Liu Xiaomai , Li Yanchun , Li Lixing , Kang Lin , Liang Zhen , Yang Shu
Published: August 2024

TGF-β stimulates CCN2 expression which in turn amplifies TGF-β signaling, thereby promoting extracellular matrix production and accelerating the pathological progression of fibrotic diseases. Alternative splicing plays an important role in multiple disease development, while U2 small nuclear RNA auxiliary factor 2 (U2AF2) is an essential pre-mRNA splicing factor in an early step of splicing. However, the molecular mechanism underlying abnormal
CCN2
expression upon TGF-β stimulation remains unclear. This study elucidates that SIRT4 acts as a master regulator for CCN2 expression in response to TGF-β by modulating U2AF2-mediated alternative splicing. Analyses of renal biopsy specimens from patients with CKD and mouse fibrotic kidney tissues revealed marked nuclear accumulation of SIRT4. The tubulointerstitial fibrosis was alleviated by global deletion or tubular epithelial cell (TEC)-specific knockout of
Sirt4
, and aggravated by adeno-associated virus-mediated SIRT4 overexpression in TECs. Furthermore, SIRT4 was found to translocate from the mitochondria to the cytoplasm through the BAX/BAK pore under TGF-β stimulation. In the cytoplasm, TGF-β activated the ERK pathway and induced the phosphorylation of SIRT4 at Ser36, further promoting its interaction with importin α1 and subsequent nuclear translocation. In the nucleus, SIRT4 was found to deacetylate U2AF2 at K413, facilitating the splicing of CCN2 pre-mRNA to promote CCN2 protein expression. Importantly, exosomes containing anti-SIRT4 antibodies were found to effectively mitigate the UUO-induced kidney fibrosis in mice. Collectively, these findings indicated that SIRT4 plays a role in kidney fibrosis by regulating CCN2 expression via the pre-mRNA splicing.
Systems genomics of salinity stress response in rice
Authors: Gupta Sonal , Niels Groen Simon , Zaidem Maricris L , Sajise Andres Godwin C , Calic Irina , Natividad Mignon , McNally Kenneth , Vergara Georgina V , Satija Rahul , Franks Steven J , Singh Rakesh K , Joly-Lopez Zoé , Purugganan Michael D
Published: August 2024

Populations can adapt to stressful environments through changes in gene expression. However, the fitness effect of gene expression in mediating stress response and adaptation remains largely unexplored. Here, we use an integrative field dataset obtained from 780 plants of Oryza sativa ssp. indica (rice) grown in a field experiment under normal or moderate salt stress conditions to examine selection and evolution of gene expression variation under salinity stress conditions. We find that salinity stress induces increased selective pressure on gene expression. Further, we show that trans-eQTLs rather than cis-eQTLs are primarily associated with rice’s gene expression under salinity stress, potentially via a few master-regulators. Importantly, and contrary to the expectations, we find that cis-trans reinforcement is more common than cis-trans compensation which may be reflective of rice diversification subsequent to domestication. We further identify genetic fixation as the likely mechanism underlying this compensation/reinforcement. Additionally, we show that cis- and trans-eQTLs are under balancing and purifying selection, respectively, giving us insights into the evolutionary dynamics of gene expression variation. By examining genomic, transcriptomic, and phenotypic variation across a rice population, we gain insights into the molecular and genetic landscape underlying adaptive salinity stress responses, which is relevant for other crops and other stresses.
Genome-wide analysis of Smad and Schnurri transcription factors in C. elegans demonstrates widespread interaction and a function in collagen secretion
Authors: Vora Mehul , Dietz Jonathan , Wing Zachary , Liu Jun , Rongo Christopher , Savage-Dunn Cathy
Published: August 2024

Smads and their transcription factor partners mediate the transcriptional responses of target cells to secreted ligands of the Transforming Growth Factor-β (TGF-β) family, including those of the conserved bone morphogenetic protein (BMP) family, yet only a small number of direct target genes have been well characterized. In
C. elegans,
the BMP2/4 ortholog DBL-1 regulates multiple biological functions, including body size, via a canonical receptor-Smad signaling cascade. Here, we identify functional binding sites for SMA-3/Smad and its transcriptional partner SMA-9/Schnurri based on ChIP-seq peaks (identified by modEncode) and expression differences of nearby genes identified from RNA-seq analysis of corresponding mutants. We found that SMA-3 and SMA-9 have both overlapping and unique target genes. At a genome-wide scale, SMA-3/Smad acts as a transcriptional activator, whereas SMA-9/Schnurri direct targets include both activated and repressed genes. Mutations in
sma-9
partially suppress the small body size phenotype of
sma-3,
suggesting some level of antagonism between these factors and challenging the prevailing model for Schnurri function. A functional analysis of target genes revealed a novel role in body size for genes involved in one-carbon metabolism and in the endoplasmic reticulum (ER) secretory pathway, including the disulfide reductase
dpy-11.
Our findings indicate that Smads and SMA-9/Schnurri have previously unappreciated complex genetic and genomic regulatory interactions that in turn regulate the secretion of extracellular components like collagen into the cuticle to mediate body size regulation.
The paradox of extremely fast evolution driven by genetic drift in multi-copy gene systems
Authors: Wang Xiaopei , Ruan Yongsen , Zhang Lingjie , Chen Xiangnyu , Shi Zongkun , Wang Haiyu , Chen Bingjie , Tracy Miles E , Wu Chung-I , Wen Haijun
Published: August 2024

Multi-copy gene systems that evolve within, as well as between, individuals are common. They include viruses, mitochondrial DNAs, transposons and multi-gene families. The paradox is that their (neutral) evolution in two stages should be far slower than single-copy systems but the opposite is often true. As the paradox cannot be resolved by the standard Wright-Fisher (WF) model, we now apply the newly expanded WF-Haldane (WFH;(Ruan, et al. 2024)) model to mammalian ribosomal RNA (rRNA) genes. On average, rDNAs have
C
∼ 150 - 300 copies per haploid in humans. While a neutral mutation of a single-copy gene would take 4
N
generations (
N
being the population size of an ideal population) to become fixed, the time should be 4
NC*
generations for rRNA genes (
C*
being the effective copy number). Note that
C*
>> 1, but
C*
< (or >)
C
would depend on the drift strength. Surprisingly, the observed fixation time in mouse and human is < 4
N
, implying the paradox of
C*
< 1. Genetic drift that encompasses all random neutral evolutionary forces appears as much as 100 times stronger for rRNA genes as for single-copy genes, thus reducing
C*
to < 1. The large increases in genetic drift are driven by the homogenizing forces of gene conversion, unequal crossover and replication slippage within individuals. This study is one of the first applications of the WFH model to track random genetic drift in multi-copy gene systems. Many random forces, often stronger than the WF model prediction, could be mis-interpreted as the working of natural selection.
Estudo dos fatores influenciadores de rotatividade de funcionários: teoria dos conjuntos Fuzzy
Authors: Luz Danielle Oliveira da , Boente Alfredo Nazareno Pereira
Published: August 2024

A alta rotatividade de funcionários é uma questão importante para as empresas devido aos impactos nos custos e na produtividade. Este estudo visa analisar os principais fatores que levam os funcionários deixarem a empresa de forma voluntária. A análise abrange temas como revoluções industriais, teorias administrativas, cultura organizacional, gestão de gerações, comunicação e pacotes de remuneração. Utilizando critérios matemáticos associados aos fatores e variáveis linguísticas através da lógica fuzzy, oferecendo flexibilidade para que as empresas possam realizar potenciais ajustes conforme necessidades específicas. Desse modo, observa-se que a aplicação dessa metodologia permite uma mensuração mais detalhada e adaptável dos fatores que influenciam a intenção de rotatividade. Os resultados indicam que a abordagem proposta facilita a identificação dos fatores relevantes e oferece flexibilidade para ajustes conforme as necessidades específicas de cada empresa permitindo obter maior precisão, redução de custos e maior retenção dos funcionários.
Evaluation of the Efficacy of a Commonly Used Antiseptic Soap in Reducing the Bacterial Load on the Palms of Some Undergraduate Students of Alex Ekwueme Federal University Ndufu Alike Ikwo, Ebonyi State, Nigeria
Authors: Rita Eze, Amarachi , Collins Onwa, Ndubuisi , Nzubechi Dick, Joy , Ozioma Okezie, Priscilia , Stellamaris Uwaezu, Ozioma , Uzondu Okezie, Prince , Onu Euslar, Nnenna , O. Nomeh, Loveth , B Ebe, Nathaniel
Published: August 2024

Introduction: The human hand serves as a carrier of microorganisms, comprising both transient and normal flora. The present study aims at evaluating the efficacy of a commonly used antiseptic soap in reducing the bacterial load on the palms of some undergraduate students of Alex Ekwueme Federal University Ndufu Alike Ikwo, Ebonyi State.
Methods: Handwashing with the antiseptic soap was carried out according to the World Health Organisation protocol on handwashing. Bacterial identification was done using morphological and biochemical characteristics, also antimicrobial susceptibility test was carried out on the identified bacterial species using agar diffusion according to the method of Clinical Laboratory Standard Institute.
Results: The result of the bacterial load indicated bacterial load of 2.0×102 before handwashing and 0.96×102 after handwashing, on plate count agar and bacterial load of 7.7×101 before handwashing and 3.2×101 on MacConkey agar, the results were statistically analyzed using Chi-square test. The following bacteria species were identified from the palms of the students after handwashing; Strep. pneumoniae, Staph. aureus, Staph. spp, Strep. spp, A. baumannii, E. coli.
Conclusion: The result of the statistical analysis showed that sanitol antiseptic soap significantly reduced the bacterial load on the palms of the participants.
Dynamics of intraoceanic subduction initiation: 2. Suprasubduction zone ophiolite formation and metamorphic sole exhumation in context of absolute plate motions
Authors: van Hinsbergen Douwe J. J. , Peters Kalijn , Maffione Marco , Spakman Wim , Guilmette Carl , Thieulot Cedric , Plümper Oliver , Gürer Derya , Brouwer Fraukje M. , Aldanmaz Ercan , Kaymakcı Nuretdin
Published: May 2015

Analyzing subduction initiation is key for understanding the coupling between plate tectonics and the underlying mantle. Here we focus on suprasubduction zone (SSZ) ophiolites and how their formation links to intraoceanic subduction initiation in an absolute plate motion frame. SSZ ophiolites form the majority of exposed oceanic lithosphere fragments and are widely recognized to have formed during intraoceanic subduction initiation. Structural, petrological, geochemical, and plate kinematic constraints on their kinematic evolution show that SSZ crust forms at fore‐arc spreading centers at the expense of a mantle wedge, thereby flattening the nascent slab. This leads to the typical inverted pressure gradients found in metamorphic soles that form at the subduction plate contact below and during SSZ crust crystallization. Former spreading centers are preserved in forearcs when subduction initiates along transform faults or off‐ridge oceanic detachments. We show how these are reactivated when subduction initiates in the absolute plate motion direction of the inverting weakness zone. Upon inception of slab pull due to, e.g., eclogitization, the sole is separated from the slab, remains welded to the thinned overriding plate lithosphere, and can become intruded by mafic dikes upon asthenospheric influx into the mantle wedge. We propound that most ophiolites thus formed under special geodynamic circumstances and may not be representative of normal oceanic crust. Our study highlights how far‐field geodynamic processes and absolute plate motions may force intraoceanic subduction initiation as key toward advancing our understanding of the entire plate tectonic cycle.
Microstructural evolution of gas hydrates in sedimentary matrices observed with synchrotron X‐ray computed tomographic microscopy
Authors: Chaouachi Marwen , Falenty Andrzej , Sell Kathleen , Enzmann Frieder , Kersten Michael , Haberthür David , Kuhs Werner F.
Published: May 2015

The formation process of gas hydrates in sedimentary matrices is of crucial importance for the physical and transport properties of the resulting aggregates. This process has never been observed in situ at submicron resolution. Here we report on synchrotron‐based microtomographic studies by which the nucleation and growth processes of gas hydrate were observed at 276 K in various sedimentary matrices such as natural quartz (with and without admixtures of montmorillonite type clay) or glass beads with different surface properties, at varying water saturation. Both juvenile water and metastably gas‐enriched water obtained from gas hydrate decomposition was used. Xenon gas was employed to enhance the density contrast between gas hydrate and the fluid phases involved. The nucleation sites can be easily identified and the various growth patterns are clearly established. In sediments under‐saturated with juvenile water, nucleation starts at the water‐gas interface resulting in an initially several micrometer thick gas hydrate film; further growth proceeds to form isometric single crystals of 10–20 µm size. The growth of gas hydrate from gas‐enriched water follows a different pattern, via the nucleation in the bulk of liquid producing polyhedral single crystals. A striking feature in both cases is the systematic appearance of a fluid phase film of up to several micron thickness between gas hydrates and the surface of the quartz grains. These microstructural findings are relevant for future efforts of quantitative rock physics modeling of gas hydrates in sedimentary matrices and explain the anomalous attenuation of seismic/sonic waves.
Orientations and aspect ratios of falling snow
Authors: Garrett Timothy J. , Yuter Sandra E. , Fallgatter Cale , Shkurko Konstantin , Rhodes Spencer R. , Endries Jason L.
Published: May 2015

Photographs of nearly 73,000 snowflakes in free fall are used to determine the aspect ratio and orientation of aggregates, moderately rimed particles, and graupel. Observations indicate that there can be a much broader range of orientation angles, with a larger median value, than has been indicated by previous observational and theoretical studies. The data show that aspect ratio depends on riming extent but that orientation is only weakly dependent on the degree of riming and on particle size. Instead, more vertical orientations for frozen particles become increasingly common with higher turbulence. The results suggest that distributions of size, fall speed, orientation, and aspect ratio may each need to be considered in order to optimize the accuracy of precipitation retrievals using microwave sensors.
RNAModification
Authors: Motorin Yuri
Published: May 2015

Naturally occurring ribonucleic acids (RNAs) contain over 150 chemically altered nucleosides formed by enzymatic modification of the primary RNA transcript during the complex tRNA maturation process. This post‐transcriptional RNA modification is a universally conserved and highly complex metabolic process in the living cell. Cellular RNAs are modified by pure protein stand‐alone enzymes, as well as by s(sno)RNP complexes containing guide s(sno)RNAs. Modified nucleotides present in RNA play an important role in stabilisation of 2D and 3D structures of these molecules, as well as in the fine‐tuning of numerous interactions between RNAs itself and with RNA‐binding protein partners. Modification also protects RNAs against nucleolytic degradation and improves their performance in different interactions in which various RNAs are involved. For example, modifications present in the tRNA anticodon loop are crucially important for correct mRNA decoding during the protein synthesis on the ribosome. Recent progress in the field points out the regulatory character of RNA modification. This emerging concept of ‘RNA‐epigenetics’ supplies the additional level to the regulation of gene expression. This regulation (and deregulation) of RNA‐modification machineries is a basis for some important human pathologies.

Key Concepts

Cellular RNAs are post‐transcriptionally modified in all life kingdoms

RNA modification alters physico‐chemical properties of nucleotides, including their conformation, polarity, hydrophobicity, chemical reactivity and base‐pairing interactions

RNA modification is performed by highly specific and regulated enzymatic mechanisms involving pure protein enzymes and catalytic RNA–protein complexes (RNPs)

RNA modification is important for regulation of gene expression

Transcription‐wide RNA modification is dynamic and regulated cellular process

Deregulation of RNA modification may lead to important human pathologies
Chlorophylls
Authors: Fujita Yuichi
Published: May 2015

Chlorophylls (Chls) are a group of cyclic tetrapyrrole pigments that are involved in the light reactions of photosynthesis. There are many Chls differing in chemical structures; Chls
a
,
b
,
c
,
d
and
f
and bacteriochlorophylls (BChls)
a
,
b
,
c
,
d
,
e
,
f
and
g
. All Chls are classified into three groups by their parental structure; porphyrins, chlorins and bacteriochlorins. Upon absorption of light the Chl molecule transitions into the first excited singlet state, and the captured energy is transferred to the neighbouring Chl molecules reaching the reaction centre Chl molecules to ignite the photosynthetic electron transfer. All Chls are synthesised from 5‐aminolevulinic acid via multiple enzymatic reactions. The first half of this biosynthetic pathway is shared with haem biosynthesis and the second half is specific for Chls, which is the so‐called magnesium (Mg) branch. In the Mg branch, the reactions from protoporphyrin IX to chlorophyllide
a
constitute a common pathway for all Chls.

Key Concepts

Chlorophylls have a central role in light harvesting and ignition of photosynthetic electron transfer.

Chlorophylls are functionally divided into antenna chlorophylls and reaction centre chlorophylls.

A variety of chemically different chlorophylls absorb different wavelengths of light, and photosynthetic organisms have specific sets of chlorophylls for utilising light in their natural habitats.

All chlorophylls are synthesised from 5‐aminolaevulinic acid, and the subsequent six reactions leading to protoporphyrin IX are common to haem biosynthesis.

Five reactions from protoporphyrin IX to chlorophyllide
a
are shared with the biosynthetic pathways of all chlorophylls.

The diversity of the biosynthetic pathways of different chlorophylls results from the evolution of photosynthetic organisms to adapt their light environments.

Chlorophyll biosynthesis is tightly regulated by multiple layers of regulatory mechanisms to avoid photooxidative damage caused by biosynthetic intermediates.

Elucidation of the reaction mechanisms of enzymes involved in the magnesium branch is one of the most important goals in plant physiology.
Mitochondria: Structure and Role in Respiration
Authors: Fontanesi Flavia
Published: May 2015

Mitochondria are eukaryotic organelles of endosymbiotic origin, which conserve their own genome and gene expression machinery. They are highly dynamics organelles and form an elaborated network in the cell cytosol. Mitochondria fulfil various important roles in cellular metabolism. They are commonly known as ‘the powerhouse of the cell’ for their pivotal role in the conversion of nutrient‐derived energy in the form of ATP molecules, through the mitochondria‐housed pathways of citric acid cycle and oxidative phosphorylation. Besides, much broader is the role that these organelles play in cellular metabolism and survival. Mitochondria fulfil important roles in the biosynthesis of essential molecules, such as lipids, amino acids, haem and iron–sulphur cluster, and are a major cellular site of reactive oxygen species production. Moreover, mitochondrial dysfunction is the cause of devastating human encephalomyopathies and it has been linked with neurodegeneration, cancer and ageing.

Key Concepts

Mitochondria are semi‐autonomous organelles that are descendants of endosymbiotic bacteria.

Mitochondria play a pivotal role in cellular energy production through the mitochondria‐housed pathways of citric acid cycle, fatty acid oxidation, respiration and oxidative phosphorylation (OXPHOS).

Mitochondria have an important anabolic role in cellular metabolism, as they are fundamental for the synthesis of several amino acids, nucleobases and enzymatic cofactors such as haem and Fe‐S clusters.

Mitochondria are membrane‐bound organelles. They have two distinct membranes: the outer and the inner membrane. The inner membrane is highly impermeable to ions and forms an extensive series of invaginations called cristae.

In the cell, mitochondria form a continuous and highly dynamic network. In addition, they intimately interact with other cellular structures, such as the cytoskeleton and the endoplasmic reticulum.

Mitochondria retain their own hereditary material, the mitochondrial DNA (mtDNA), and their own translation apparatus or mitoribosomes.

mtDNA is present in ∼1000–10 000 copies per cell and encodes for a handful of proteins, all subunits of the OXPHOS system.

The OXPHOS system is located in the mitochondrial cristae and is formed by the mitochondrial respiratory chain (MRC) and the ATP synthase or complex V. The MRC is formed by four multimeric complexes (complex I–IV) and two mobile electron carriers, coenzyme Q and cytochromec. In addition, MRC complexes interact to form organised supra‐structures called supercomplexes or respirasomes.

The assembly of the OXPHOS complexes is a complicated and highly regulated process requiring a large number of ancillary factors.

In humans, defects of the OXPHOS system are associated with devastating diseases, known as mitochondrial disorders, which are multisystemic, although mainly affecting highly energy‐demanding tissues such as brain, heart and muscle.
Phospholipases
Authors: Vines Charlotte M , Bill Colin A
Published: May 2015

Phospholipases play central roles in regulating signalling during numerous cellular events including proliferation, G protein‐coupled receptor signalling and neuronal activation by catalysing the lysis of phosphorylated lipids. In turn, second messengers are released, which control downstream events. Four distinct families of phospholipases have been described and are named A, B, C and D and range in size from 13 to 250 kDa. These enzyme family members are categorised based on the stereospecifically numbered sites within phospholipids where they promote cleavage. Within the phospholipase families, there are isoforms, which have differential distribution patterns and functions within specific cell types. These enzymes are widely expressed, can be regulated by different substrates or by [Ca2+] and can be found in the cytoplasm, membrane and in a soluble form outside of cells. Within the cytoplasm, different family members can be found within distinct organelles, including the mitochondria. In this article, we discuss these enzymes, their expression patterns and identified functions for each family member.

Key Concepts

Four different families of phospholipases control levels of phospholipid substrates by cleaving different sites of phospholipids.

Phospholipases are ubiquitously expressed in nature.

Phospholipase families are either calcium‐dependent or calcium‐independent enzymes.

Enzymes are often found in membranes, but some phospholipases are secreted.

Phospholipases have important functions in membrane integrity, digestion and cell signalling.

Phospholipases are important in health and certain disease states.
Nucleus and Nuclear Envelope: Methods for Preparation
Authors: Jafferali Mohammed H , Beckman Marie , Kihlmark Madeleine , Hallberg Einar
Published: May 2015

The nucleus of eukaryotic cells contains the genome surrounded by a nuclear envelope (NE) consisting of two lipid membranes with embedded nuclear pores and an underlying nuclear lamina. The uniformity in size and density makes it possible to isolate pure intact nuclei at high yields from tissue homogenates by centrifugation through a sucrose cushion. NEs can be prepared from isolated nuclei by enzymatic degradation of their nucleic acid content. The resulting NE preparations contain structurally well‐conserved inner and outer nuclear membranes with attached ribosomes, nuclear pore complexes and nuclear lamina. Reliable methods for preparation of nuclei and NEs play an important role in the successful identification of components and their interacting partners that are located in nuclei and in nuclear subcompartments.

Key Concepts

Pure intact nuclei can be isolated at high yields from tissue homogenates, and nuclear envelopes can be prepared from the isolated nuclei.

The preparation of pure nuclei is important for the identification of nuclear and subnuclear components and their interacting partners.

Animal behaviourists must participate in conservation planning to protect the future of biodiversity.

Lipid bilayers provide the fundamental architecture of biological membranes.