Computational Model of Effective Thermal Conductivity of Green Insulating Fibrous Media

Modelling effective thermal properties is crucial for optimizing the thermal performance of materials such as new green insulating fibrous media. In this study, a numerical model is proposed to calculate the effective thermal conductivity of these materials. The fibers are considered to be non-overlapping and randomly oriented in space. The numerical model is based on the finite element method. Particular attention is paid to the accuracy of the results and the influence of the choice of the representative elementary volume (REV) for calculation (cubic or rectangular parallelepiped slice). The calculated effective thermal conductivity of fibrous media under different boundary conditions is also investigated. A set of usual mixed boundary conditions is considered, alongside the uniform temperature gradient conditions. The REV rectangular slice and uniform temperature gradient boundary conditions provide a more accurate estimate of the effective thermal conductivity and are therefore recommended for use in place of the usual cubic representative elementary volume and the usual mixed boundary conditions. This robust model represents a principal novelty of the work. The results are compared with experimental and analytical data previously obtained in the literature for juncus maritimus fibrous media, for different fiber volume fractions, with small relative deviations of 7%. Analytical laws are generally based on simplified assumptions such as infinitely long fibers, and may neglect heat transfer between different phases. Both short and long fiber cases are considered in numerical calculations.

[Management Of Blader Exstrophy In Children At The CHU Gabriel Touré]

AIMS

To describe the clinical and evolutionary aspects of the primary closure of exstrophy at the CHU Gabriel Touré.

MATERIALS AND METHODS

This was a retrospective and prospective study carried out from January 2014 to December 2019 in all the children admitted and operated on for bladder exstrophy at the CHU Gabriel Touré.

RESULTS

We collected 35 cases of exstrophy, ie25 boys and 10 girls. The mean age at diagnosis was 4.8 months. The bladder plate was both normal and budded, ie 28.6% of cases. Plaque infection was found in 45.7%. A malformation was associated in 34.3% of cases. Primary plaque closure was achieved in all of our patients. Postoperative morbidity was 28.6% of cases and mortality 11.4% of cases.

CONCLUSION

Bladder exstrophy is a rare malformation of the urogenital sphere, its management is complex and its mortality is not null.

[Particularities of early neonatal bacterial infection in the hospital environment of the CHU Gabriel Touré in Bamako]

INTRODUCTION

Early neonatal bacterial infection (ENBI) is a major concern in neonatology. In Mali, no study had addressed this aspect, hence the initiation of this work to study the epidemiological-clinical, biological and bacteriological profile of ENBI.

MATERIALS AND METHODS

This was a descriptive longitudinal study that took place from june 27 to september 3, 2016 involving newborns aged ≤ 72 hours hospitalized for ENBI confirmed by blood culture in the neonatology service of the pediatrics department of the Center Hospitalier et Universitaire (CHU) Gabriel Toure in Bamako. The parameters studied were the socio-demographic and obstetrical characteristics of the mothers, the clinical, biological and bacteriological characteristics of newborns infected early.

RESULTS

Of the 324 blood cultures performed, 52 were positive, i.e. an ENBI frequency of 11.04%. The sex ratio was 1.3 with 73.1% low birth weight. On admission, 90.4% of newborns had less than 24 hours of life and 86.5% were births outside the CHU Gabriel Toure. The main clinical signs were hyperthermia or hypothermia and respiratory distress. The main bacteria isolated in blood culture were Staphylococcus aureus (55.8%), Klebsiella pneumoniae (13.5%) and Escherichia coli (07.7%). Sensitivity to first-line biantibiotic therapy (ceftriaxone + gentamicin) was low (63.6%) and that of amikacin was better (100%). Half of the newborns infected early died and 19.2% of exeat without medical agreement was recorded.

CONCLUSION

Early neonatal bacterial infection is a major cause of neonatal morbidity and mortality. In our context, amikacin could be a better therapeutic alternative.

[Acute bursa of the child in pediatric surgery at the teaching hospital Gabriel Touré]

Acute bursa is a medico-surgical emergency because of its many etiologies threatening the functional prognosis of the testes and their appendages.

OBJECTIVES

Identify the causes of acute bursaries in the child and describe their clinical and therapeutic aspects.

MATERIALS AND METHOD

This was a retrospective descriptive study from January 1, 2010 to December 31, 2015 on all children aged 0 to 15 years received and treated for acute scholarship in the Pediatric Surgery department at the teaching hospital Gabriel Touré.

RESULTS

In 6 years, we registered 42 patients, ie a frequency of 1.4% of surgical emergencies. The mean age was 2.98 years (24 days-14 years). Prematurity represented 11.9% of cases. Painful scrotal tumefaction was the main reason for consultation (76.2%), The main aetiologies were HISE (90.5%), scrotal trauma (4.7%), orchi epididymitis (2.4%) and testicular torsion (2.4%). The treatment was surgical in 97.6% of cases. The course after 3 months was simple in 97.6% of cases.

CONCLUSION

Acute bursa in children is an uncommon condition, especially affecting infants. Strangulated inguino-scrotal hernia was the main aetiology. The diagnosis must be early and the treatment adequate in order to reduce morbidity and mortality.

[Portal cavernoma at child about two observations]

We report two observations of portal cavernoma diagnosed successively in Bamako and Dakar. The first is a 6-year-old male admitted to the service for ascites and abdominal pain. At admission the clinical parameters (weight, height, temperature, cranial perimeter and temperature) were within the norms for age. The clinical examination noted a moderate skin-mucosal pallor, asthenia. The biological assessment returned to moderate normochrome anemia with impaired pancreatic function while renal and hepatic functions were maintained. The abdominal scan performed after two low-contribution abdominal ultrasounds, objected signs in favor of a portal cavernoma with perisplenic and gastric varicose veins. The second is an 8-year-old male child born from an unborn marriage and from a followed pregnancy with premature delivery. His pathological history includes a notion of prematurity that required a stay in neonatology with umbilical catheterization and repeated abdominal pain. He had an acute abdominal episode in March 2015 justifying a surgical hospitalization for suspicion of appendicitis. At admission the clinical parameters (weight, height, temperature, cranial perimeter and temperature) were within the norms for age. The abdominal ultrasound prescribed for this was suggestive of portal cavernoma, later confirmed by abdominal computed tomography.

[Cystic meningioma of falx cerebri: About one case and literature review]

Cystic meningioma of the falx is a rare extra-axial tumor, representing 4 to 7% of all intracranial meningioma. We report the case of a 23 years old patient with relative personal health history who has presented for nearly two years generalized headache associated with left hemiparesis. The head CT scan and MRI showed a right posterior parietal tumor with a cystic and fleshy component which was interpreted as glioma. The patient was operated and the intraoperative aspect was an extra axial lesion inserted to the middle tier of the falx cerebri with a clear cleavage plan with the cerebrum. A total ablation of the lesion was down and the histological study confirm the diagnosis. The cystic meningioma is a rare variant of intracerebral meningioma of which only histology makes it possible give the diagnosis of certainty.

[Endoscopic surgery and covid 19 disease: case report]

The objective of this work is to raise the issue of contamination of covid 19 disease during endoscopic endonasal surgery for pituitary tumor. This is a 32-year-old patient with a body mass index at 49,38 seen in an outpatient clinic for headache, erectile dysfunction and gynecomania, a CT scan revealed a pituitary macroadenoma. The preoperative workup was unremarkable including the rapid polymerase chain reaction (PCR) test was negative. The endonasal approach was decided for surgery. The tumor was removed by aspiration. The postoperative course was straightforward until the fifth day when the patient presented a dry cough with a fever at 38 ° 5 associated to respiratory discomfort. The thoracic CT-scan showed "ground glass" opacities located at peripheral and bilateral, and essentially posterior suggesting covid 19 disease. A second test was performed. Before the result, the anticoagulant treatment associated with third generation cephalosporin was done. The test results came back after 72 hours and was positive. Azithromycin, hydroxychloroquine, and oral vitamin C have been used for 11 days. The outcome was favorable and the patient was discharged from the hospital on the twelfth day after the negative PCR test.

[Diagnosis and surgical traitment of intracerebral hydatic cyst in Mali]

AIMS

Cerebral hydatic cysts are common in North African and pastoral countries but still underdiagnosed in sub-saharian ones.We report the first two casesoperated in Mali andhistologically proven of cerebral hydatic cysts.

PATIENTS AND METHOD

Our study was aboutabout a 46 years old patient, admitted for Bravais-Jacksonian crisis, dysarthry and right hemiparesy, and another 38 years old male one, with a intracranial hypertension syndrome associated with cranial fistulized cerebral hydatic cyst.The CT scan has shown a cerebral cyst in the first case and multi-locular cysts in the second. The patients underwent surgery, with complete removal in one case and a rupture in the second case, but with a good outcome. Anatomo-pathological analysis concluded to hydatic cerebral cysts in both cases.

CONCLUSION

With these first cases, the diagnosis of cerebral hydatic cyst must be evoked more frequently in our countries, because of the evolution of radiological diagnosis and surgical abilities.

[Management of Acute Malnutrition in Children in a Sahelian Secondary Hospital]

Malnutrition among children under five is a major public health problem in low-income countries, and contributes significantly to mortality in this age group. The purpose of this work was to evaluate the epidemiological and clinical profile of malnourished children at the Nara hospital in north of Mali.

METHOD

It was a retrospective and descriptive study, from 01/01/2016 to 31/12/2016. Children aged 6 months to 59 months admitted for acute malnutrition were included.

RESULTS

Four hundred and sixty-one children had malnutrition, representing 15% of consultations and 50% of hospitalizations. The median age was 26 months (2 months-93 months). The sex ratio was 0.92 (M = 222, F = 239). Nineteen percent of the patients had progressive weaning (n = 90), and it was brutal in 371 patients (80%). The distribution of patients according to the Z-score was as follows: Z-score <-1 (n = 15, 3%), Z-score <-2 (n = 46, 10%), Z-score <-3 (n = 400, 87%). Mean MUAC was 105 mm (99mm-124mm). Hypoglycemia was noted in 45% (n = 204). The marasmus cases accounted for 80% (n = 367) kwashiorkor 10% (n = 48). The mixed form of malnutrition accounted for 10% (n = 46). The disease associated with malnutrition were pneumonia (n = 219, 47%), malaria (n = 115, 25%) and gastroenteritis (n = 68, 15%). The F75 milk was administered predominantly for 3 months in 93% of cases. For phase 2 of treatment, Plumpy Nut and F100 milk were respectively administered in 88% and 12%. The nutritional recovery rate was 95% (n = 435). Five percent of the patients died (n = 26). Pneumonia was the cause of death in 85% of cases. The cure rate for marasmus and kwashiorkor cases was respectively 94% and 93%.

CONCLUSION

Acute malnutrition remains frequent in the Sahelian environment. Better knowledge of mothers about weaning and dietary diversification will improve the nutritional status of children.

[Healthcare associated infections in the neurosurgical department of Gabriel Touré teaching Hospital in Bamako]

INTRODUCTION

Healthcare-associated infections or nosocomial infections are a public health problem due to their frequency, severity and economic impact. They cause an increase of the morbidity, the mortality, the hospital stay and the expenses of taking care of the patients. According to the WHO, 7.1 million people are affected each year, of which about 100,000 die.

AIM OF STUDY

The aim of this study was to determine the frequency of healthcare-associated infections in the Neurosurgery Department of Gabriel Touré University teaching Hospital and to identify the risk factors associated with these infections.

MATERIAL AND METHODS

This was an epidemiological, descriptive, analytic, cross-sectional and prospective study lasting 6 months from May 29 to November 30, 2016. The study focused on patients who stayed more than 48 hours in the Neurosurgical department Gabriel Touré teaching hospital. The collected data focused on the clinical and biological characteristics of the patients during their hospitalization. The maximum size of the sample was 200 patients. A sample was taken for each type of infection. The criteria used for the diagnosis of Healthcare-associated infections were those of the CDC (Center for Disease Control) and the realization of a thick drop in our context. The chi-square test was used for the comparison of qualitative variables and Kruskal Wallis and Anova for quantitative variables. The materiality threshold has been set to a value of p less than 0.05.

RESULTS

At the end of our study, we had 34 infected patients out of 200, a rate of 17%. The significant risk factors found in our study were: high age (p = 0.04), ASA class (p = 0.002), pre-surgical shaving (p = 0.02), long duration surgical intervention (p = 0.002) and long hospital stay (p = 0.004). The types of infections associated with the care found were: urinary in 18 (53%) cases, respiratory in 9 (26%) cases, operative site in 6 (18%) cases and 1 (3%) cases of bacteremia. The bacterial spectrum of these infections was dominated by Negative Gram Bacilli, among which Escherichia coli in 11 (32.3%) cases. The clinical course of patients treated for these infections was marked by healing in 31 (91.2%) cases, complications in 2 (5.9%) cases, and death in 1 (2.9%) case.

CONCLUSION

The prevalence of Healthcare-associated infections in our department remains high compared to that found in developed countries. This study allowed us to identify the main risk factors associated with these infections. A stricter adherence to the rules of hygiene and prevention of Healthcare-associated infections is needed to reduce this rate.

Childhood brain tumors in Mali

to assess epidemiologic and clinical aspects of childhood brain tumors in Mali. a retrospective, descriptive study of children aged 0-15 years with brain tumors, conducted in the pediatrics department of the Gabriel Touré University Hospital Center in Bamako, Mali, from January 31, 2007 to December 3, 2012. In all, 41 cases of brain tumors were recorded during this period (mean: 5.5 years old; range: 1-12 years). Brain tumors were most frequent in the children aged 2-5 years (53.7%) and among boys (53.7%). Late stage at presentation was relatively frequent (34.1%) with a mean time to diagnosis of 10 months. Features of elevated intracranial pressure were the most frequent mode of revelation of primary tumors (26.8%). Supratentorial tumors accounted for 83% of the cases, and gliomas were most frequently (29.3%) identified on computed tomography. Only five patients underwent surgical tumor removal. A broader study including the other hospitals in Bamako could help to assess more accurately the epidemiology of pediatric brain tumors in Mali.

[Caracteristics Of Severe Malaria In Child From 0 To 5 Years At The Hospital Of Sikasso In Mali]

In Mali, malaria is a major public health problem. The region of Sikasso is classified according to the geo-climatic facies as a zone with a long seasonal transmission of malaria greater than 6 months.

OBJECTIVE

To describe the epidemiological, clinical and therapeutic characteristics of children aged 0- 5 years hospitalized for severe malaria in the pediatric ward of the Sikasso hospital. Variables analyzed were epidemiological, clinical, paraclinical, therapeutic and evolutionary.

PATIENTS AND METHODS

This is a retrospective, 12-month (January-December 2014) cross-sectional study of all 0-5-year-olds hospitalized for severe malaria at the Sikasso Regional Hospital.

RESULTS

The hospital frequency of severe malaria was 55.82%. The age group of 12-35 months was the most concerned (45.3%). The peak frequency was in August (21.2%). Anemic, mixed (anemia and neurological) and neurological forms were the most frequent. Artemether and quinine were the antimalarials used. The use of a blood transfusion was frequent (82.8%). The lethality was 10% and the mixed form (anemia and neurology) was the most lethal ((P<10^-6).

CONCLUSION

Malaria remains a national concern in Mali. Improving the quality of care and prevention must be a priority to reduce the lethality that remains high.

[Accidental household poisoning of the child at the Gabriel Toure university hospital center in Bamako]

INTRODUCTION

Household accidental child poisonings are frequent pediatric medical emergencies in developing countries.

OBJECTIVE

To study the epidemiological, etiological, clinical and therapeutic aspects of acute accidental domestic poisoning in children aged 0 to 15 years admitted to the pediatric emergency department of Gabriel Toure.

METHOD

This was a prospective, descriptive study that ran from January 1, 2014 to December 31, 2014. All patients aged 0 to 15 years admitted to pediatric emergencies for acute intoxication were included.

RESULTS

A hundred cases of acute accidental poisoning were collected. Children under five accounted for 94%. The majority of mothers was housewives and had custody of children (83%). Forty-nine percent of the mothers were unschooled. The place of storage of the product was indoor in 96% of cases. The product was taken by the child himself (88%). A gesture at the scene of the accident was reported in 68% of cases, the ingestion of milk (72%) and water (10%) were the first acts used. The hospital was the first resort (72%). The time between taking the product and admission to hospital was 1 to 5 hours in 58% of cases. Vomiting (37 cases), agitation (17 cases) and respiratory distress (16 cases) were the most common symptoms. Domestic products (48%) followed by drugs (33%) ranked first among the families of poisons. Caustic soda (18%) and bleach (17%) were the most commonly found intoxication products. The evolution was good with a cure without sequelae (93%).

CONCLUSION

Accidental acute intoxications to household products are common in Mali. The hospital admission deadline is still long; the actions taken by patients at the accident site often aggravate their states but are largely done by the parents before the use of health care.

[Pathologies of peritoneo-vaginal canal in pediatric surgery at the teaching hospital Gabriel Touré]

The closure anomalies of the peritoneal-vaginal canal include several clinical entities, which are at the origin of various symptomatology.

OBJECTIVE

To study the anatomo-clinical and therapeutic aspects of pathologies of the peritoneal-vaginal canal.

MATERIALS AND METHOD

This was a prospective study from January 1^st to December 31^st, 2015 carried out in the pediatric surgery department of University Hospital Gabriel Touré. It covered all children aged 0-15 years old with a pathology of the peritoneal-vaginal canal operating in the department during the study period. This study did not include cases that were not operated on or not seen during the study period.

RESULTS

During the study period, 2,699 children were treated in pediatric surgery, of which 150 cases of pathology of the peritoneal-vaginal canal had a hospital frequency of 5.5%. The average age was 3.25 ± 9.63 years. The sex ratio was 14. The reason for consultation was intermittent or permanent inguinal or inguino-scrotal swelling in all children. The pathology was discovered by the parents during the pushing efforts in 46.7%. Inguino-scrotal swelling was found on physical examination in 40% of cases. The right side was reached in 60% of the cases. Hernia accounted for 80.6% of these pathologies. We recorded 31 cases of strangulation and 11 cases of craze. Immediate operative follow-up was simple in 92% of patients. This rate was 96% after 6 months.

CONCLUSION

Pathologies of the peritoneal-vaginal canal are very common in pediatric surgical practice. The first place of these pathologies is occupied by hernia. They preferentially affect male infants.

Giant occipital meningohydroencephalocele in an adult: Another historical case in neural tube defects

Meningohydroencephalocele is a herniation of meninges, cerebrospinal fluid, brain parenchyma and a part of the ventricular system through a bony defect in the skull. This bone defect may be congenital, spontaneous or traumatic in origin. The lesions are mostly congenital, discovered generally after birth or in very young infants. We report the first historical case of the entity in this location in a 29-year-old man and discuss the pathogenesis, surgical management and social considerations of this type of neural tube defect in our country.

[Epidemiological, clinical and therapeutical study of depressed skull fractures in the neurosurgical department of the gabriel toure hospital: about 72 cases]

INTRODUCTION

Depressed skull fractures are common and frequent among neurosurgical diseases of whose danger stem from the associated intracranial lesions. The aims of this study were to describe the epidemiological characteristics of depressed skull fractures, to determine their etiology, to describe the clinical signs, to highlight the complications and sequelae and to evaluate care management.

PATIENTS AND METHODS

It was a retrospective and descriptive study from January to December 2013 including 72 patients admitted to the neurosurgical department of the Gabriel Toure hospital.

RESULTS

The frequency was 14.7% and the male to female ratio was 13.4. The peak frequency of these injuries occurred in the 16-to 25-year-old age group accounting for 38.9% of cases. Road traffic accidents were the most common causes of depressed skull fractures (59.7%). Neurosurgical treatment was performed in 25 (34.72%) patients and the most common surgical technique performed was the craniectomy in (64%). Infection of the wound was found in 15.3% and the mortality rate was 1.39%.

CONCLUSIONS

Depressed skull fractures are a frequent neurosurgical disease in the Gabriel Touré hospital. Young people are most affected and road traffic accidents involving motorbikes are the main cause the fractures. The infection of the wound is a poor prognostic factor. Therefore, an early management is required to expect a good outcome.

[Clinical and therapeutical aspects of lumbar stenosis in the gabriel touré hospital: about 24 cases]

INTRODUCTION

Lumbar stenosis is a disease caused by a conflict between the neural structures (spinal cord and nerve roots) and spinal structures (bones and ligaments). The objectives of this study were to highlight the frequency, the diagnosis and therapeutics options, and to evaluate the treatment outcomes.

PATIENTS AND METHODS

It was a retrospective study from January 2012 to December 2012 including 24 patients admitted to the neurosurgical department of the Gabriel Touré Hospital.

RESULTS

The frequency of lumbar stenosis was 6.19% of all neurosurgical diseases. The sex-ratio was 0.71. The age ranged from 28 to 81 years with an average of 52 years. The neurogenic claudication was found in 87.5%. The straight leg raising test was positive in 41.7% of cases. The most vertebras involved were L4 and L5. Lumbar disc herniation was associated in 70.83%. Degenerative lumbar stenosis was the most common form, found in 66.67% of cases. Surgical treatment was performed in 29.17% of cases. The outcome was good in 85.6% of cases.

CONCLUSIONS

Lumbar stenosis is a prevalent disease that occurs typically occurs around 50 years of age. The diagnosis was confirmed by myelography and a post myelographic CT scan. Good outcomes are achieved with both surgical or medical treatments.

[Complications of digestive ostomies in pediatric surgery]

AIMS

To determine the frequency and factors of complications of intestinal stomas.

METHODS

This was a retrospective study over a 7 year period from January 2004 to December 2010, covering all children aged 0-15 years, who received a stoma and hospitalized in the period of study. Excluded from this study, alimentary ostomy and urological ostomy, and children whose medical records were incomplete.

RESULTS

We examined 192 cases of stoma or 27 cases/year. We noted a complication in 91 (48%) of our patients. The average age was 3.64 ± 5.03 years ranging from 6 hours and 15 years. The complicating factors were: the indication for surgery, type of stoma, the variety of stoma, surgical technique and equipment.

CONCLUSION

The achievement of good technique and appropriate equipment would be needed to reduce some complications of the stoma.

Effect of storage conditions on microbiological and physicochemical quality of shea butter

Storage conditions are key constraints for quality assurance of the shea (Vitellaria paradoxa Gaertner) butter. In the Sudan savannah Africa, storage conditions of butter produced by women vary across and among processors, traders and consumers. These conditions could impact the quality of the products and reduced their access to international market. The present study attempted to investigate the effect of storage duration and packaging materials on microbiological and physicochemical characteristics of shea butter under tropical climatic conditions. Five packaging materials traditionally used in shea butter value chain were tested for their efficacy in storing shea butter freshly produced. Total germs, yeasts and mould varied with packaging materials and storage duration. After 2 months of storage, moisture content of butter remained constant (5%) whereas acid value increased from 3.3 to 5.4 mg KOH/g, peroxide value from 8.1 to 10.1 meq O2/kg and iodine value dropped from 48.8 to 46.2 mg I2/100 g in shea butter irrespectively to the storage materials used. The basket papered with jute bag was the less effective in ensuring the quality of butter during storage while plastic containers and plastic bags seemed to be the best packaging materials.

[Chronic left parietal endocarditis. Clinical, paraclinical and peroperative study of 22 cases]

From 22 patients with left chronic parietal endocarditis (CPE), conducted an epidemiological, clinical, paraclinical and per-operative study. The CPE is frequently encountered in the Ivory Coast in Akan children living in forest areas in 81 p. cent of the cases. It causes a mitral insufficiency, of the which the essential mechanism is fibrosis of the sub-valvular apparatus. The clinical examination is that of a severe advanced mitral insufficiency. Cardiomegaly is the rule. In 31 p. cent of cases, the ECG shows a Qr in V1. The dip plateau on the apexocardiogram is never found and the protodiastolic endocardial resonance is inconstant on phonomechanical processor. The aspect in M of the interventricular septum, found in 72 p. cent of the cases on echo TM is of major importance when direct signs are missing on bidimensional sonograms. Angiocardiography remains the reference diagnostic examination. But only the surgical survey enables to demonstrate limited forms.