bluuebunny/crossref_metadata_2025 huggingface dataset:
USING ENVIRONMENTAL ISSUES TO TRIGGER THE STUDENTS’ CRITICAL THINKING IN ESSAY WRITING CLASS
Authors: Setyowati Lestari , Sukmawan Sony , El-Sulukiyyah Ana Ahsana
Published: February 2020

The advancement of technology and information in this 21st century brings heavy consequences on the environment. Therefore, the young generation needs to be introduced and educated about the environmental issues so that they become an active agent in environmental protection.  The use of environmental issues in the language classroom offers wide opportunity for the students to think and respond critically to the environmental problem. This paper is intended to describe the students’ ability in writing an  essay  by using an environmental topic about  the use of  water. The design of the study is content analysis design. The sujects of the study  were 32 students of 2017 batch taking essay writing course in the academic year 2018-2019. The instrument used was mainly documentation. The result of the study showed that almost two thirds (72%) of the students were able to state a thesis statement. The majority of the students (88%) were able to give elaboration and explanation in the body of the essay, but 66% of them failed to give details and examples. Most of the students developed the essay by using cause and effect, problem solution, and reasoning paragraph organization. Not not all students were able to write a proper conclusion for the essay. The conclusions written by the students mostly contained advice (62%) of what others should do to preserve nature.
A Research on the Spherical Indicatrices of Directional Space Curve
Authors: UĞUR KAYMANLI Gül , EKİCİ Cumali , DEDE Mustafa
Published: February 2020

In this paper, we give a parametrization of a directional space curve by using adapted frame called q-frame.. The spherical images of both directional normal indicatrix and directional tangent indicatrix of this space curve with q-frame are studied. Later using the geodesic curvature of the spherical image of the directional normal indicatrices, we work on the condition that a space curve to be slant helix. Finally, we give an application of the results.
Minkowski Uzayında Asli Regle Yüzeylerin Kesit Eğriliği
Authors: ERSOY Soley , TOSUN Murat
Published: February 2020

Bu
çalışmada, n-boyutlu Minkowski
uzayında timelike doğrultman uzaylı merkez regle yüzeyli genelleştirilmiş
timelike regle yüzeyin dayanak eğrisinin merkez noktalarında verilen asli
ışınların dayanak eğrisi boyunca hareketiyle oluşan 2-boyutlu asli regle
yüzeyler göz önüne alınmıştır. Böylece 2-boyutlu timelike asli regle yüzeyinin
kesit eğriliği ile asli dağılma parametresi arasındaki bağıntı elde edilmiş ve
bu bağıntının 3-boyutlu Minkowski uzayındaki bir timelike regle yüzeyin Gauss
eğriliği ve dağılma parametresi arasındaki bağıntının genelleştirilmişi olduğu
görülmüştür. Benzer şekilde spacelike asli regle yüzeyinin kesit eğriliği ile
asli dağılma parametresi arasındaki bağıntı elde edilmiştir. Bu bağıntının da
3-boyutlu Minkowski uzayındaki bir spacelike regle yüzeyin Gauss eğriliği ve
dağılma parametresi arasındaki bağıntının genelleştirilmişi olduğu
belirlenmiştir.
Retained iatrogenic foreign body causing persistent non-healing wound: a case report
Authors: Waquad Aisha , Patel Hiren , Gandhi Mai , Gabriel Guny
Published: February 2020

An 88-year-old female presented with non-healing wound of left hip, found to have iatrogenic foreign body. The patient presented at the age of 88 with complaints of a persistent wound of left hip. She had a previous incision and drainage of an abscess on her left hip and subsequently received negative pressure therapy. She underwent a wound exploration and found to have multiple foreign bodies in the wound. While uncommon, iatrogenic foreign body should be considered as a possible differential diagnosis in patient with non-healing wounds. The literature on iatrogenic foreign body is reviewed. Iatrogenic foreign body is an uncommon pathology but should be included in the differential diagnosis in patients presenting with a non-healing wound.
A prospective study on microbiological profile and antimicrobial resistance pattern in chronic suppurative otitis media at a rural centre
Authors: John Nikhil Mathew , N. Balachandrakurup , Varghese Tija Susan
Published: February 2020

Background: Over and injudicious prescription of antibiotics over the years has resulted in change in microbial flora in chronic suppurative otitis media (CSOM). More over the incidence of multidrug resistance in bacteria is increasing alarmingly. This study was done to know the microbial pattern in CSOM in the current scenario. This study also aims to know the microbial resistance pattern and the drug sensitivity, also how to tackle the growing multidrug resistance in current practice.

Methods: Sterile swab was collected from 100 patients who attended Outpatient Department of our hospital during 1 year period, sent for culture sensitivity. Details like age distribution, sex distribution, microbial pattern, MDR susceptibility pattern were evaluated.  

Results: Males were commonly affected. Most common age group was in the 5th decade followed by 4th decade. Staphylococcus aureus was the most common pathogen followed by Pseudomonas. All the multi drug resistant (MDR) strains were Pseudomonas, and were sensitive to only higher antibiotic like Piperaziccilin Tazobactam (PTZ), Imipenem (IMP) with 2 of them only intermediate sensitivity to IMP.

Conclusions: Staph aureus and Pseudomonas are the most common pathogen in CSOM. Incidence of MDR is on the rise even to higher line drugs. Hence pus culture and sensitivity should be made mandatory in every case of CSOM before starting higher antibiotics or putting patient on long term treatment. This will prevent the emergence of multidrug resistant strains.
Management of a giant euthyroid goiter in limited resources settings: case report
Authors: Kikuhe Nzanzu , Akomu Munyatwari , Safari Sekabuhoro , Vululi Sosthene Tsongo , Namwagala Justine
Published: February 2020

The cases of giant multinodular goiter are rare clinical conditions nowadays. We present here a case of giant multinodular goiter successfully treated at Hôpital Provincial du Nord Kivu (Regional referral hospital and Goma teaching hospital). A 59 years old man with 40 years’ history of gradual growing of an anterior cervical mass. The patient reported compressive symptoms such difficulty in breathing, hoarseness of the voice and difficulty in swallowing during the last nine months prior to our consultation. A total thyroidectomy was performed as well as a one year of follow-up, showing good evolution.
A comparative study of functional outcome between platelet rich plasma injection versus steroid infiltration in plantar fasciitis
Authors: Singh Harpreet , Gandhi Malay P. , Rampurwala Aliasgar J. , Rudani Tej S.
Published: February 2020

Background: Plantar fasciitis (PF) is considered as degenerative tendinopathies. Repeated micro trauma is the major etiology of these diseases. Autologous platelet rich plasma (PRP) injections are becoming more popular in the treatment of enthesopathies like PF. The growth factors in PRP cause tissue healing. We compared the result of injecting intra-lesional autologous PRP injections versus steroid infiltration in chronic PF.

Methods: A prospective, interventional and analytic comparative study was done and 81 patients (120 heels) were included in this study and were followed up for 6 months. We assessed the outcome of each patient using visual analog score (VAS) and foot and ankle disability index (FADI) on follow-up at 1, 3, and 6 months.

Results: In our study, female preponderance was seen. Left side was more common as compared to right side. Unilateral PF is more common than bilateral. The difference with in the individual group at baseline and at 1,3 and 6 months was statistically highly significant in terms of VAS and FADI (p=0.0001) But the difference in the between the two groups was insignificant for VAS and FADI at 1, 3 and 6 months.

Conclusions: In our study, as there is no significant difference in VAS and FADI score between corticosteroid injection group and PRP injection group at 1, 3 and 6 months follow up. So, it’s reasonable to conclude that both are equally effective in PF. But as PRP injection comes out to be more time consuming and more costly, corticosteroid seems to be more efficient, cost and time wise. Hence, the latter should be a better choice.      
Clinical, epidemiological and autoimmune associations in childhood vitiligo in Qatar
Authors: Al Mannai Haya , Allam Mohamed , Riad Hassan
Published: February 2020

Background: Childhood vitiligo although clinically similar to adult onset vitiligo but it has distinct clinical, epidemiological and prognostic features compared to adult onset vitiligo.

Methods: This is a retrospective study that was carried out on 85 pediatric patients up to age of 18 years old with the diagnosis of vitiligo, where the clinical and epidemiological data  including clinical type of vitiligo, family history of autoimmune diseases like thyroid disorders and diabetes mellitus and laboratory results including anti-thyroid peroxidase antibodies (anti-TPO antibodies), anti-parietal cell antibodies, antinuclear antibodies (ANA), Vitamin D and Vitamin B12 were retrieved from the files of these patients.

Results: The mean age of the children affected by vitiligo was 10.4 years, the mean age of onset of vitiligo was 5.4 years, 54 (63.5%) percent were girls and 31 (36.5%) were boys. A positive family history of vitiligo was found in 44.7% of the participants, family history of DM was found in 64.7% of patients and family history of thyroid disease was found in 32.9% of the participants. The prevalence of thyroid autoimmunity was found to be in 22.4% of total participants.

Conclusions: Childhood vitiligo has distinct clinical features, more common family history for autoimmune diseases and thyroid autoantibodies rather than overt clinical diseases, which raise the necessity to perform a routine initial immunological and thyroid screening in children with vitiligo and to repeat them at annual bases if there were abnormal values at base line or strong family history.
A study of clinico pathological spectral correlation in multibacillary leprosy
Authors: Sanker Anita , Mathew P. S. , Nandakumar G. , George Sandhya , Binesh V. G.
Published: February 2020

Background: Leprosy expresses itself in different clinico-pathological forms, depending on the immune status of the host.The diagnosis and classification of leprosy have traditionally been based on the clinical examination with additional information from skin smears and histopathological examination. Very often, disparities between clinical and histopathological findings are observed. This study was aimed to correlate between clinical and histopathological spectral correlation of newly diagnosed multibacillary leprosy cases for a period of 1 year.

Methods: The study was conducted in the Department of Dermatology and Venereology, Government Medical College, Thiruvananthapuram, for a period of 1 year. All newly diagnosed multibacillary leprosy cases were included.

Results: A total of 40 patients with clinically diagnosed multi bacillary leprosy were studied. Maximum numbers of leprosy patients studied were in the age group of 40-49 years. Maximum clinical and histopathological correlation was found in 75% (9/12) in lepromatous leprosy and least correlation of 44.44% was noted in borderline lepromatous (4/9).

Conclusions: In this study maximal clinico-histopathological spectral correlation was found in lepromatous  spectrum. The percentage of correlation was considerably less in all the other groups.
Clinical trends of scalp alopecia areata: a tertiary care hospital based observational study
Authors: Singh Pallavi , Patvekar Milind A. , Shah Bhavika , Mittal Alisha , Kapoor Asmita
Published: February 2020

Background: Alopecia areata is one of the commonest types of non-scarring alopecia involving the scalp and/or body. As there is paucity of recent epidemiological data from our country, this study was conducted to determine the latest clinical and epidemiological trends of scalp alopecia areata.

Methods: A hospital-based observational study consisting of 100 cases of clinically diagnosed scalp alopecia areata who reported to the Dermatology OPD, Dr. D.Y. Patil Medical College, Pune, was conducted for a period of six months. Socio-demographic and clinical information was collected and clinical examination was performed on all patients. The data was evaluated using appropriate statistical methods.

Results: Out of the 100 cases enrolled, males (64%) outnumbered females (36%). The commonest presenting age group was 21-30 years (44%). Disease onset was sudden in 80% patients and 59% cases had a progressive disease course. Majority (75%) had a disease duration of less than 3 months. Majority cases were asymptomatic (80%) with no precipitating factors (90%). Past history and family history of alopecia areata were present in 13% and 9% cases, respectively. Personal and family history of associated diseases were present in 27% and 22% patients, respectively. Most patients had single (61%), patchy (83%) lesions with occiput (45%) being the commonest initial site. Nail changes were present in 22% cases, of which pitting (13%) was the commonest nail finding.

Conclusions: This study reflects the clinical profile of scalp alopecia areata in a tertiary care hospital.
Case reports on erosive pustular dermatosis of scalp: a cross sectional study at a tertiary care centre
Authors: Solanki Avanitaben D. , Nagrani Neha S. , Patel Dhara V. , Patel Neela M. , Barot Jigna P. , Arora Anisha V. , Patel Jahnavi H.
Published: February 2020

Erosive pustular dermatosis of the scalp (EPDS) has been reported as a rare chronic and progressive non-infectious inflammatory condition of the actinically damaged scalp characterized by crusts, erosions and pustules. It tends to occur on the scalp of older people who have usually been treated for diffuse actinic damage and actinic keratoses. The list of possible differential diagnosis is long and includes tinea capitis, folliculitis decalvans, neutrophilic dermatosis, autoimmune vesiculobullous disorders, malignancy etc. Notoriously difficult to treat, these cases tend to be chronic and progressive. These patients often present after repeated treatment to various scalp dermatosis that doesn’t result in clearing instead persistence and perpetuation of the process. A cross sectional prospective study was conducted in department of dermatology in a tertiary care centre in which six cases of EPDS attending outpatient department from 2017 to 2019 were included. EPDS is more common but under recognized condition, hence less cases are reported till date. Increased awareness of and proper diagnosis of this condition changes the approach towards these patients, protects the scalp from involuntary insults and other precipitating factors that hinders with a better outcome.
Platelet rich plasma in dermatology and cosmetology
Authors: Mohan Shobhit , Mohan Lalit , Sangal Renu , Singh Neelu
Published: February 2020

Platelet rich plasma (PRP) therapies in medicine has become increasing popular during the last decade. The interest in in the application of PRP in dermatology and cosmetology has increased recently in different applications such as alopecia, skin rejuvenation, wound healing, scar revision, and tissue regeneration. PRP is an autologous blood product obtained from the blood of the patients. The detailed knowledge about PRP should help clinicians better understand this therapy. In this view, the current review was done for a better understanding of what pathologies can be corrected with PRP.
Safety of voriconazole in treatment of fungal infections
Authors: Mohan Shobhit , Mohan Lalit , Sangal Renu Sangal , Singh Neelu
Published: February 2020

Immunocompromised patients are at more risk in developing fungal infections particularly with Candida and Aspergillus species being the mycoses most commonly identified. Previously, amphotericin-B is the drug of choice for the treatment of systemic infections caused by Candida and Aspergillus species. Due to its high incidence of toxicity, its use has been limited in many cases. Voriconazole is the newest triazole synthesized against fungal infections and was approved by FDA in 2002 for the treatment of invasive aspergillosis and refractory infections of Scedosporium apiospermum and Fusarium spp.
Los derechos humanos de los pueblos indígenas en México
Authors: Gutiérrez Hernández Alejandro
Published: February 2020

Los derechos humanos de los pueblos indígenas son un tema que aún se debate en México. El objetivo de este trabajo es identificar y describir el marco normativo de derechos humanos de estos pueblos para comprender las imposibilidades del cumplimiento de esos derechos. Para tal objetivo se aplicó el método hermenéutico analógico, promovido por Mauricio Beuchot. A través de tal método pretendemos comprender el problema de los derechos humanos de los indígenas en México. Resultado de este análisis es que los derechos humanos de primera generación están plenamente garantizados para estos pueblos, sin embargo, las reformas hechas a la Constitución General Mexicana del 2001, que pretendían resolver algunos problemas ancestrales de la relación de los pueblos indígenas con el Estado mexicano, vinieron a dar avances en unas áreas de estos derechos, aunque en otras quedó algo de ambigüedad respecto a algunos derechos de fundamental importancia.
Directions in the research of the legacy of Sabina Grzegorzewska of the Gostkowskis (based on the material of the Scientific Library of the PAAS and the PAS in Cracow)
Authors: Berkan-Jabłońska Maria
Published: February 2020

The aim of the article was to describe the collection of manuscripts preserved in the family archives as a memorial to Sabina Grzegorzewska née Gostkowska, a 19th‑century writer, which are currently in the possession of The Scientific Library of the PAAS and the PAS in Cracow. That analysed archival legacy consists of various documents, which include a few letters, several rough drafts with notes and quotations on Grzegorzewska’s philosophical and religious lectures, excerpts from her dissertations, and drafts and fair copies of novels and memoirs. The article presented their content and material condition. The prospects for further processing of that legacy were also discussed. An important issue is the question on the importance of the task for the history of Polish literature of the 19th century, especially with regard to the creator of minorum gentium. According to the author of the article, it would be reasonable to link the methods of the analysis of avant-textes, adopted in genetic research, with the proposals of the so-called cultural genetics.
Wolność czy może ciąg dalszy „zniewolenia”, czyli o nowych polskich zjawiskach kulturalnych na Litwie
Authors: Dalecka Teresa
Published: February 2020

Artykuł jest opisem kondycji kultury polskiej na Litwie i środowiska ją tworzącego. Zostały zdiagnozowane przyczyny słabości tej kultury, takie jak m.in. pogarszająca się sytuacja demograficzna litewskich Polaków czy zła sytuacja gospodarcza regionu, który w przeważającej większości zamieszkują. Zły stan wynika też z braku inteligencji polskiej na Litwie po II wojnie światowej oraz powolność procesu jej odradzania się. Przyczyn słabości upatruje się ponadto w etnocentryzmie tej kultury, skoncentrowaniu się na sobie i braku zainteresowania innymi grupami etnicznymi. Mimo wszystko w ostatnich latach na Wileńszczyźnie podejmowane są próby wyrwania się z ograniczeń, związanych z kulturą kresową. Została założona grupa poetycka „Nowa Awangarda Wileńska”, ukazała się powieść Cień słońca czy zbiór opowiadań Thriller po wileńsku. Jest to inne niż dotychczas zaprezentowanie polskości na Litwie.
THE ANALYSIS OF STUDENTS’ PRONUNCIATION ERRORS IN READING ALOUD
Authors: Budiman Mutiana , Kania Ikeu
Published: February 2020

It was aimed to identify students’ pronunciation errors in reading aloud by finding out how far the students’ pronunciation errors in reading aloud and kind of words which are pronounced by the students through reading aloud. Qualitative method was used to find out the fact and the evidence of students’ pronunciation errors in reading aloud. The observation and the interview were conducted to explore the student’s experience and their problems in pronouncing English.The findings revealed that there were satisfactory results proved that the students made pronunciation errors in six part of speech; Nouns, Verbs, Adjectives, Adverbs, Prepositions and Conjunction. It was found that 26 pronunciation errors in noun (26.8%), 49 pronunciation errors in verb (50.5%), 6 pronunciation errors in adjective (6.2%), 12 pronunciation errors in adverb (12.4%), 3 pronunciation errors in preposition (3.1%) and 1 pronunciation error in conjunction (1.03%) from 7 students who had read the same narrative text. The reasons why the students made errors in pronouncing the words were the students have difficulties in pronouncing and spelling the words with affixes and prefixes in consonants, vowels, and diphtongs. They are: upon, aunt, lived, died,answered, knocked, cottage, dwarf, enough.
Elemento añadido y teoría de la recepción: un análisis del cuento La siesta del martes de Gabriel García Márquez
Authors: Padilla Villada Edwin Mauricio
Published: February 2020

En este trabajo se analiza la convergencia de dos poéticas: la Teoría de la recepción, según los planteamientos de Hans Robert Jauss, y el Elemento añadido, enunciado por Mario Vargas Llosa. En el análisis, la pregunta general se centra en la relación que puede existir entre estas dos teorías y la correspondencia de las añadiduras del autor y la descodificación del elemento añadido para una recepción exitosa. Por lo tanto, se estudia el cuento La siesta del martes [1962] de Gabriel García Márquez (1927-2014) para encontrar tales vínculos y comprender, en última instancia, el valor literario y el universo de creación del autor con los que se garantiza la recepción de la obra y la posterior perdurabilidad.
Variaciones sobre un episodio de Facundo. Autores en proceso: Domingo F. Sarmiento, José M. Paz y Eduarda Mansilla
Authors: Dellarciprete Rubén
Published: February 2020

El siguiente escrito parte de la lectura de una anécdota protagonizada por Facundo Quiroga y contada por Sarmiento en el capítulo “La ciudadela” de su libro Facundo. El anecdotario de las guerras civiles de mediados del siglo diecinueve acumula más de una versión acerca de episodios que reúnen similares características, entramado que nos permitió abordar la secuencia como un corpus de estudio. José María Paz en sus Memorias y Eduarda Mansilla en Pablo o la vida en las pampas, retoman la anécdota de Sarmiento pero alternan los personajes que la interpretan a la vez que habilitan lecturas contrapuestas. Por otra parte, realizaremos además un relevamiento de la condición autoral, principalmente cuando abordemos las fuentes textuales y pictóricas de la escritura sarmientina.
Free to choose: Female characters in the stories of Grazia Deledda
Authors: Caocci Duilio
Published: February 2020

Grazia Deledda’s strategies of female characters’ construction and agency are at the core of this essay. The goal is to investigate how the Nobel prize winner shapes the identity as the actions of her female characters in a decidedly eccentric manner if compared to contemporary Italian narrative. The path of the essay is chiefly chronological as it starts from her first short stories 1888, published in the context of widely circulated periodicals, to ends with Cosima, the autobiographical novel published in 1936, the year of Deledda’s death. A typology of her characters emerges in relation both to the cultural assumptions that strongly influence the first production of Deledda as well as to the heterogeneous literary models with which the writer weaves a dense and uninterrupted dialogue.
In Silico Identification of Novel B Cell and T Cell Epitopes of Wuhan Coronavirus (2019-nCoV) for Effective Multi Epitope-Based Peptide Vaccine Production
Authors: Rasheed Muhammad Asif , Raza Sohail , Zohaib Ali , Yaqub Tahir , Rabbani Masood , Riaz Muhammad Ilyas , Awais Muhammad , Afzal Amna
Published: February 2020

During December 2019, a novel coronavirus named as 2019-nCoV, has emerged in Wuhan, China. The human to human transmission of this virus has also been established. Untill now the virus has infected more than seven thousand people and has spread to fifteen countries. The World Health Organization (WHO) has declared 2019-nCoV as global health emergency due to its outburst well beyond China. There is need to develop some vaccines or therapeutics to control or prevent 2019-nCoV infections. The bottleneck with current conventional approaches is that these require longer time for vaccine development. However, computer assisted approaches help us to produce effective vaccine in short time compared with conventional methods. In this study, bioinformatics analysis was used to predict B cell and T cell epitopes of surface glycoprotein of 2019-nCoV that could be suitable to trigger significant immune response. The sequence of surface glycoprotein was collected from the database and analyzed to identify the immunogenic epitope. Both B cell and T cell epitopes were analyzed so the predicted epitopes can stimulate both cellular and humoral immune responses. We predicted 13 B cell and 05 T cell epitopes that later on were joined with GPGPG linker to make a single peptide. This computational approach to design a multi epitope peptide vaccine against emerging 2019-nCoV allows us to find novel immunogenic epitopes against the antigen targets of surface 2019-nCoV surface glycoprotein. This multi epitope peptide vaccine may prove effective to combat 2019-nCoV infections.
Jet Oscillation Frequency Characterization of a Sweeping Jet Actuator
Authors: Oz Furkan , Kara Kursat
Published: February 2020

The time-resolved flowfield of a spatially oscillating jet emitted by a Sweeping Jet (SWJ) actuator is investigated numerically using three-dimensional Reynolds-averaged Navier-Stokes (3D-URANS) equations. Numerical simulations are performed for a practical range of mass flow rates providing flow conditions ranging from incompressible to subsonic compressible flows. A linear relationship between the mass flow rate and the jet oscillation frequency is found. The results of the numerical model are compared with the experimental data in the literature, and good agreement is found. Additionally, it is observed that the SWJ actuator frequency response switches from one linear mode to another linear mode when the compressibility effects become important.
Tambaqui de tanque-rede: qualidade microbiológica, valor nutricional e rendimento
Authors: Dos Santos Oliveira M.O. , De Bem Luiz D. , De Souza Martins G.A. , Rodrigues Verdolin dos Santos V.
Published: February 2020

O tambaqui é consumido tradicionalmente em tamanho comercial (1 a 3 kg), mas também entre 0,350 a 0,450 kg, sendo denominado Curumim(C). Objetivou-se avaliar a qualidade microbiológica do tambaqui em tamanho comercial (TC) e caracterizar o valor nutricional e rendimento de tambaquis em duas classes de tamanho: Curumim (C) e TC, provenientes de tanques-rede. O efeito do tamanho sobre a composição centesimal e rendimento do peixe foi avaliado em delineamento inteiramente casualizado com 12 repetições, enquanto para as análises microbiológicas, utilizou-se um peixe de cada tanque-rede. C apresentou teores de proteína (19,08%), cinzas (2,91%) e umidade (71,58%) superiores aos de TC, 17,83%, 2,00% e 68,25%, respectivamente, enquanto extrato etéreo foi maior para TC (9,25%), contra 5,16% para C. O rendimento foi de 70,04% para C e 65,55% para TC. Cinquenta por cento (50%) das amostras apresentaram contaminação por S. aureus, entretanto, dentro dos limites estabelecidos pela legislação. Constatou-se presença de salmonella em 91,67% das amostras, enquanto 75% delas apresentaram contaminação por coliformes totais e 8,34% por E. coli, denotando contaminação da água de cultivo. O C apresentou valor nutricional adequado e melhor rendimento em relação ao TC. A inserção do C nas dietas dependerá da aceitação pelos mercados onde sua comercialização não esteja estabelecida. Os resultados das análises microbiológicas realizadas com o tambaqui em tamanho comercial sugerem predisposição da espécie para o desenvolvimento de Salmonella spp. na superfície corporal.
Probing Methane Foam Transport in Heterogeneous Porous Media: An Experimental and Numerical Case Study of Permeability-Dependent Rheology and Fluid Diversion at Field Scale
Authors: Zeng Yongchao , Kamarul Bahrim Ridhwan Z. , Groot J. A. W. M. , Vincent-Bonnieu Sebastien , Groenenboom Jeroen , Mohd Shafian Siti Rohaida , Abdul Manap Arif A , Tewari Raj D. , Mohammadian Erfan , Azdarpour Amin , Hamidi Hossein , Biswal Sibani L.
Published: February 2020

This paper advances the understanding of foam transport in heterogeneous porous media for enhanced oil recovery (EOR). Specifically, we investigate the dependence of methane foam rheology on the rock permeability at the laboratory scale and then extend the observations to the field scale with foam modeling techniques and reservoir simulation tools.

The oil recovery efficiency of conventional gasflooding, waterflooding, and water-alternating-gas (WAG) processes can be limited by constraints such as bypassing effects (including both viscous fingering and channeling mechanisms) and gravity override. The problem can be more severe if the reservoir is highly fractured or heterogeneously layered in the direction of flow. Foam offers the promise to address the three issues simultaneously by better controlling the mobility of injected fluids. However, limited literature data of foam-flooding experiments were reported using actual reservoir cores at harsh conditions. In this paper, a series of methane (CH4) foam-flooding experiments were conducted in three different actual cores from a proprietary reservoir at an elevated temperature. It is found that foam rheology is significantly correlated with the rock permeability.

To quantify the mobility control offered by foam, we calculated the apparent viscosity on the basis of the measured pressure drop at steady state. Interestingly, the apparent viscosity was found to be selectively higher in the high-permeability cores compared with that in the low-permeability zones. We parameterized our system using a texture-implicit-local-equilibrium model (STARS™ simulator, Computer Modelling Group, Calgary, Alberta, Canada) to illustrate the dependence of foam parameters on rock permeability.

In addition, we created a two-layered model reservoir using an in-house simulator called modular reservoir simulator (MoReS; Shell Research, Rijswijk, The Netherlands) to elucidate the role of different driving forces for fluid diversion at the field level. We took into consideration the combined effect of gravitational, viscous force, and capillary forces in our simulation. We show that the gravitational forces prevent the gas from sweeping the lower part of the reservoir. However, the poor sweep can be ameliorated by intermittent surfactant injection to generate foam. In addition, the capillary force which hinders the gas (nonwetting phase) from entering the low-permeability region can be effectively leveraged to redistribute the fluids in the porous media, resulting in better sweep efficiency. We conclude that foam if properly designed can effectively improve the conformance of the WAG EOR in the presence of reservoir heterogeneity.
An Investigation of the Use of the Spectrograph for Correlation in Limestone Rock
Authors: Jessen F.W. , Miller John C.
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 204, 1955, pages 247–250.

Basic Problem of Correlation

In many areas where carbonate rocks form important parts of the stratigraphic sequence, stratigraphers have experienced varying degrees of difficulty in differentiating and correlating limestone and dolomite units in both surface and subsurface work. With early Paleozoic rocks of the Mid-Continent, insoluble residues yield a remarkable amount of stratigraphic data and relatively good correlations may be carried over broad distances. Unfortunately, neither such information nor electric logs and radioactive logs have been particularly helpful in interpreting the limestone sections of the Permian Basin of West Texas. This is because:the variations in the sections may be very slight;no completely satisfactory method of interpretation has been developed; andthe measurements themselves are not sensitive enough for small variations.

Also, such logs are influenced by the fluid content.

Paleontology and micro-paleontology remain the ultimate arbiters. As a routine tool, however, paleontological examination is slow and tedious. Chemical analysis may be used, but this, too, is extremely slow. Although rocks are not classified according to chemical composition, there is considerable variation with rock types. Correlation by chemical composition has two advantages, first, the characteristics determined are subject to minimum human error and interpretation, and secondly, the lithologic changes are not masked by fluid content as in the case of electric and radioactive logs. Some fossils concentrate certain elementswhich tentatively might be used to date rock units.

Rapid chemical analysis by spectrographic means could be used as an adjunct to other means employed in correlation work, or might, in itself, present a suitable method.
A Study of Electric Log Interpretation Methods in Shaly Formations
Authors: De Witte Leendert
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 204, 1955, pages 103–110.

A review is given of the principles on which recently proposed methods of electric log interpretation in shaly sands are based and of the evidence brought up in support of the theoretical derivations. It is pointed out that the qualitative techniques suggested to date have a tendency to be too pessimistic in the prediction of the presence of commercial hydrocarbon accumulation.

In the quantitative treatment, a new concept is introduced, namely that of strongly reduced activity of the double layer counter ions which are present near the negatively charged rock surfaces. This lemma when applied to the calculation of the equilibrium concentrations of interstitial waters yields a set of very simple relations. The resulting expressions for electrochemical potentials across rock samples appear in satisfactory agreement with laboratory experiments. The formulae obtained for the electrical conductivity of shaly formations are of the same form as those arrived at empirically by previous workers. Combination of the expressions for potentials and conductivities gives a direct proof of the Tixier relation which states that for shaly water sands the product of apparent formation water resistivity and apparent formation factor equals the resistivity of the sand 100 per cent saturated with formation water and which was verified by the work of Wyllie and Perkins and their co-workers.

The relations for the resistivities and spontaneous potentials have been extended to the case of hydrocarbon bearing shaly formations, thus laying a formal basis forthe quantitative interpretation of electric logs in shaly oil sands.

Introduction

The presence of disseminated clays in porous rocks saturated with electrolytic solutions has a strong influence on the transference of ions taking place under electrical or chemical potential gradients. Both the electrochemical emf's in evidence on the SP curves of electric logs and the electrical conductivity measured on resistivity logs are directly dependent on the ionic transference in the interstitial waters of the formations traversed by boreholes.
The Encroachment of Injected Fluids Beyond the Normal Well Pattern
Authors: Caudle B.H. , Erickson R.A. , Slobod R.L.
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 204, 1955, pages 79–85.

In predicting the sweepout pattern efficiency to be expected in a secondary recovery operation, the reservoir engineer is often confronted with a situation in which part of the producing formation lies between the last row of wells and the reservoir boundary. To date, there has been little or no reference in the literature to sweepout pattern efficiencies in such areas. This paper presents the results of a laboratory study in which the area contacted around the edge of a reservoir injected in a five-spot pattern was determined. The X-ray shadowgraph technique was used in this study.

It was found that surprisingly large portions of the reservoir area lying outside the well network are contacted by the injected fluid before abandonment conditions are reached. In fact, it can be said that at least 90 per cent of the area lying outside the last row of wells and within a distance of one well spacing of these wells will ultimately be contacted by the injected fluid in the case of most water floods. From the results given in this paper, it is possible to estimate not only the extent to which encroachment into these areas will occur but also the injection volume necessary to produce the wells to abandonment conditions.

Introduction

While considerable work has been done in recent years evaluating the fraction of the reservoir contacted as a function of the mobility ratio for several different well patterns, there has been practically no mention of what happens to the oil in that portion of the reservoir which lies between the last row of wells and the reservoir boundary. In fact, the assumption is generally made that little or no recovery can be expected from this area.
Performance of Water Drive Reservoirs, Including Pressure Maintenance, as Determined by the Reservoir Analyzer
Authors: McDowell James M.
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 204, 1955, pages 73–78.

A study has been made to determine how the behavior of a water drive reservoir changes as a function of the permeability of the formation and ay a function of the size of the aquifer. The effect of pressure maintenance programs' on the rate of natural water influx is also studied, as well as the influence on the influx of the position of water injection wells with reference to the oil-water contact.

The results are determined by the use of an electrical reservoir analyzer and are plotted as families of curves of pressure, natural water influx, and water injection vs time or cumulative production. Two size aquifers are studied. One is limited with a 36-mile radius, and the other approximates an infinite reservoir. The field remains the same in all respects for the complete study except that the permeability is changed to agree with that assumed for the aquifer.

Introduction

This study was undertaken in order to determine how the pressure decline and water influx of a water drive field would change as a function of the rate of fluid withdrawals, as a function of the permeability of the formation, and as a function of the size of the aquifer. The effect of pressure maintenance programs on the rate of natural water influx was also studied as was the position of water injection wells with reference to the oil-water contact.

The information has been determined by the use of an electrical reservoir analyzer sometimes referred to as a Carter type analyzer. This instrument is an analog type computer which can be set up to represent a water-drive oil field. It can reproduce the past performance of the field in terms of analogous electrical quantities when the proper circuit analog of resistors and condensers has been determined, also, it can determine the future behavior for any method of production which may be selected, or permit the comparison among several different methods.
Corrosion of Oil Well Casing by Earth Currents
Authors: DeWitte Leendert , Radd Fred J.
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 204, 1955, pages 66–72.

In many areas casing failures can be directly related to electrical currents observed in the casings. It is the thesis of this paper that the observed casing currents are mainly due to electrochemical potentials of the type in evidence on spontaneous potential curves of electrical logs. The general nature of these potentials are discussed and an equivalent circuit is given for current and potential distributions around open holes. The casing forms a short circuit to these potentials and tends to average the effects of local cells. The case of casing corrosion opposite the Dakota water sands in the salt-mud area of Kansas is discussed and used as a qualitative illustration of the relation between SP's and casing currents. A method of quantitative derivation of casing current distribution from electric log SP curves, using linear transform theory, is described and results are compared with a measured current profile. The effects of hydrogen over-potentials at the cathodic portions of the pipe are considered and some laboratory data are given in support of conclusions regarding the overvoltages.

Introduction

To date an appreciable amount of work has been done on the measurement of oil well casing currents and on the correlation of the anodic portions of the current profiles with corrosive casing failures. Speculations on the origin of the casing currents have, however, remained rather vague; and although almost every plausible cause has been mentioned, there is to the writers' knowledge no clear-cut expose' on the details of the causes of the corrosive currents in the literature.

A study of current surveys and casing failures in the N.W. Burnett field, Ellis County, Kan., indicated the probability that concentration cell emf's between the Wellington salt section and the relatively fresh waters in the Dakota sands were a major cause of the corrosion currents. A more general concept evolved upon analysis of the severe corrosive conditions in the Pleistocene sands in the Ventura Avenue and San Miguelito fields in California.
The Concept "Hydraulic Radius" in Porous Media
Authors: Harmsen G.J.
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 204, 1955, pages 274–277.

It is shown that in any isotropic porous medium there is a fixed ratio between the numerical value of the total pore perimeter per unit of cross-section and the specific surface area per unit of bulk volume. The consequences of this fact on the use of the concept "hydraulic radius" in the case of porous media are examined.

The validity for consolidated sands of Kozeny's relationship and of the formula derived by Carman for capillary rise are discussed.

Introduction

In the course of time several quantities and relations have been put forward in order to describe the texture of a porous medium and the flow of fluid through it. Among these relations the so-called Kozeny formula and a formula for capillary rise, for both of which Carman has given a derivation, will be specially considered here. These relations are of a semi-empirical nature and the derivations must be considered to have a heuristic significance only.
Single-Fluid Five-Spot Floods in Dipping Reservoirs
Authors: Prats M. , Strickler W.R. , Matthews C.S.
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 204, 1955, pages 160–174.

To gain an insight into the deviations from normal behavior caused by dip, a mathematical study has been made of single-fluid five-spot floods in dipping reservoirs for flooding techniques likely to be employed in such cases. Streamline patterns and sweep efficiencies are computed for a number of different cases, and the results, where possible, are presented in graphical form. An increase in sweep efficiency can be obtained by moving the central injection well updip, and the optimum position is found for several cases. The applicability of the results is discussed.

Introduction

Because of the growing importance of water flooding in California and in other locations where large angles of dip are quite common, it is important to know at least some of the effects of dip on the performance characteristics of water floods in such instances. In the past, only reservoirs having relatively mild dips have been waterflooded. Consequently, little is known today as to the effect of dip on the performance characteristics of a flooding operation from the point of view of field experience; and because of the complexity of the problem, little, if anything, has been done on the problem from the point of view of theory.

There are two distinct aspects of the role played by gravity in a flooding operation. The first is that of the preferential segregation of the reservoir fluids at the time when the flood is to commence. The second is the role that it may play in affecting the performance of the reservoir during the course of the flooding operation. In this paper the reservoir is assumed to be filled with only one fluid, so that there is no preferential segregation of reservoir fluids at the commencement of the flood. Moreover, the injected and in-place fluids are assumed to have the same characteristics, so that in effect we consider only a single-fluid problem.
Material Balances in Expansion Type Reservoirs Above Bubble Point
Authors: Hawkins Murray F.
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 204, 1955, pages 267–271.

Introduction

One problem of reservoir engineering is the early estimation of the size of newly discovered reservoirs. Often these reservoirs are the expansion type in which sizeable pressure drops occur incident to the production of small fractions of the oil reserve, above the bubble point, and a material balance equation may be solved to find the reserve.

The early form of this equation considered only the compressibility of the oil. Later Hall showed that the compressible nature of the formation rock is a significant factor in production above the bubble point, and he presented a new equation which includes a formation (rock) compressibility term.

This note presents a further extension of the material balance equation as applied to volumetric, unsaturated reservoirs above the bubble point by including a term for the presence and compressible nature of the interstitial water.