72 research outputs found

    Bio-regeneration of activated carbon: A comprehensive review

    Get PDF
    © 2018 Elsevier B.V. The use of microorganisms to regenerate activated carbon (AC), bio-generation, can avert costly and logistically challenging ex-situ steam regeneration of carbon normally required to recover its adsorptive capacity. Bio-regeneration employs microbial metabolism in which the microbes use the available organic substrates (contaminants) to generate energy. During this process, they generate equivalent protons and electrons, which are transferred to the substrates to finally break them down to simpler molecules or ions, such as CO2, methane and Cl−. The optimal microbial conditions depend on the temperature, available nitrogen and phosphorus levels, dissolved oxygen levels, and microbe/substrate stoichiometric ratios and the residence time of the AC particles within the reactor. In this review, the authors highlight the most recent development in bio-regeneration including the regeneration mechanism, the relationship between the reversibility of adsorption and the efficiency of bio-regeneration, the general aspects affecting bio-regeneration, the principle and target compounds for bio-regeneration, different established methods for quantifying the bio-regeneration and the efficiency of bio-regeneration. Few case studies of bio-regeneration of activated carbon loaded with different contaminants are presented. Research on microbiology regeneration has gained considerable attention in recent years, but it still needs more contribution from other disciplines including process engineering, biochemistry and material sciences for optimizing the process performance

    Hormonal, follicular and endometrial dynamics in letrozole-treated versus natural cycles in patients undergoing controlled ovarian stimulation

    Get PDF
    The objective of this study was to compare letrozole-stimulated cycles to natural cycles in 208 patients undergoing intrauterine insemination (IUI) between July of 2004 and January of 2007. Group I (n = 47) received cycle monitoring only (natural group), Group II (n = 125) received letrozole 2.5 mg/day on cycle days three to seven, and Group III (n = 36) received letrozole 5 mg/day on cycle days three to seven. There were no differences between the groups in endometrial thickness or P4 on the day of hCG. Estradiol levels had higher variation in the second half of the follicular phase in both letrozole-treated groups compared to the control group. Estradiol per preovulatory follicle was similar in both letrozole cycles to that observed in the natural cycles. LH was lower on the day of hCG administration in the letrozole 2.5 mg/day group vs. the natural group. In summary, letrozole results in some minor changes in follicular, hormonal and endometrial dynamics compared to natural cycles. Increased folliculogenesis and pregnancy rates were observed in the letrozole-treated groups compared to the natural group. These findings need to be confirmed in larger, prospective studies

    Akl Fuzzy Logic Support System for Predicting Building Damage Due to the Association of Three Parameters of Pipeline Failure

    Get PDF
    Abstract: In this study, a fuzzy logic decision support tool (FLDST) was constructed for three parameters of sewer pipeline failure to get the total influence of these parameters on building damage. The effect of the shape and number of membership functions was investigated. The well-known computer program "ANSYS+ CivilFEM" is used to investigate the influence of pipeline settlement, settlement location, building location with respect to pipeline, soil stiffness and burial depth on the building damage category. The results were implemented in a fuzzy based assessment system for reinforced concrete building structures to evaluate the damage category of buildings due to the association of three parameters of pipeline failure. A criterion to define membership functions, their shape and their number, for each parameter as well as the rule base covering the whole range of all parameters was described. Several examples were run by MATLAB and were validated by ANSYS to evaluate the FLDST in predicting the damage category of building. The category of damage based on FLDST was consistent with that obtained from ANSYS calculations with great efficiency and time saving

    Impact of Lambda Value on Combustion Characteristics and Emissions of Syngas-Diesel Dual-Fuel Engine

    Get PDF
    A deep understanding of the ignition characteristics of syngas-diesel under different lambda values is essential for the application of dual-fuel combustion. In this study, the effect of increasing the lambda value was examined along with the emission characteristics and engine performance of syngas-diesel dual-fuel engines under a constant syngas-to-diesel substitution ratio of 52% at 2000 rpm engine speed. The work involved computational fluid dynamics analysis related to combustion for a four-stroke single-cylinder direct-injection engine. Combustion analysis was carried out using ANSYS Workbench (FLUENT) V16.1 software. According to the simulation results, the maximum pressure, temperature, and nitric oxide emission inside the combustion chamber increased with each increase in the value of lambda, while the emission of carbon dioxide and carbon monoxide decreased inside the engine

    FEKALNA INKONTINENCIJA Nova koncepcija: Uloga unutarnjeg analnog sfinktera pri defekaciji i fekalnoj inkontinenciji

    Get PDF
    Introduction. Fecal incontinence is involuntary escape of stool, mucus and/or flatus.Its causes are: anal sphincter damage (childbirth trauma, surgical trauma.); constipation; diarrhea; rectocele; rectal prolapse and rarely congenital causes. Fecal material entering the rectum is evacuated by defecation during which: 1. The smooth muscles of the distal colon and rectum contract, propelling the feces into the anal canal; 2.The anal sphincter relaxes allowing defecation to occur. We put forward a recent concept on the patho-physiology of defecation.The mechanism of defecation has two stages: first stage: (in early childhood) before training; second stage is after training. The mother starts to teach her child how to control himself. This is gained by maintaining high alpha sympathetic tone at the internal anal sphincter (IAS) keeping it closed all the time till appropriate place and time are available. Wherever appropriate place is available and there is a desire, six neuromuscular actions will occur: 1) the person will lower the acquired high alpha sympathetic tone at the IAS relaxing it opening the anal canal; 2) through the voluntary nervous system (NS) he will widen the ano-rectal angle to bring the anal canal and the rectum on one axis. This is done through the pelvic floor muscles; 3) through, voluntary NS he will also relax the external anal sphincter (EAS); then synergistic actions between the voluntary and autonomic nervous system occur; 4) the abdominal and diaphragmatic muscles contract, increasing the intra- abdominal pressure and forcing the feces through the anal canal (via the voluntary NS); 5) the smooth muscles of the distal colon and rectum contract, propelling the feces into the anal canal (through the autonomic NS); 6) followed by sequential contractions of the three parts of the EAS (deep then superficial and then the subcutaneous parts) that will squeeze the anal canal propelling any residual contents. Objectives. Imaging of the anal canal by 3-dimension ultrasound (3DUS) in normal women and women suffering from fecal incontinence and from rectocele, to compare the state of the IAS and EAS. Methods. 40 patients with FI were assessed clinically and by imaging using 3DUS, and also 10 normal women not suffering from fecal incontinence (FI) as a control. Results. The anal canal is closed in normal women, with intact IAS. In women suffering from FI the anal canal is wide and open with torn IAS. Conclusion. The internal anal sphincter (IAS) is a collageno-muscular tissue cylinder that surrounds the anal canal innervated by alpha-sympathetic nerve supply from the hypogastric nerves. It is surrounded in its lower part by the EAS which is a striated muscle innervated by the pudendal nerve. Its damage during childbirth causes fecal incontinence, and mending its torn wall restores fecal continence.Uvod. Fekalna inkontinencija (insuficijencija stolice) znači nevoljno bježanje stolice, sluzi i/ili vjetrova. Uzroci su: oštećenje sfinktera (pri rađanju djeteta, kirurška trauma), zatvor stolice, proljev; rektokela, ispadanje rektuma, rijetko prirođeno ispadanje. Stolica ulazi u završno crijevo te iz njega izlazi na sljedeći način: 1. Glatki mišići donjeg i završnog dijela debelog crijeva se stežu, potiskujući feces u analni kanal; 2. Analni sfinkter olabavi i omogući da uslijedi defekacija. Predstavljamo svježe shvaćanje o patofiziologiji defekacije. Mehanizam ima dva razdobkja: prvo razdoblje je rano djetinstvo, bez poduke; drugo razdoblje je nakon poduke. Majka podučava svoje dijete kako se kontrolirati. To se postiže visokim alfa simpatičkim tonusom unutarnjeg analnog sfinktera, držeći ga zatvorenim sve dok se ne ukaže odgovarajuće mjesto i vrijeme. Kad se nađe odgovarajuće mjesto, i ako postoji želja, počinje šest sinergističkih neuromuskularnih aktivnosti: 1) osoba će sniziti postojeći visoki alfa simpatički tonus unutarnjeg analnoga sfinktera i time otvoriti analni kanal; 2) pomoću voljnog živčanog sustava smanjit će ano-rektalni kut i dovesti ih u istu osovinu; to postiže pomoću mišića dna zdjelice: 3) voljnim živčanim sustavom također će omlohaviti vanjski analni sfinkter; tada nastupa sinergistična djelatnost voljnog i autonomnog živčevlja; 4) trbušni i dijafragmalni mišići se stežu, povećavaju intraabdominalni tlak te potiskuju feces kroz analni kanal; 5) stežu se glatki mišići debelog crijeva i rektuma te potiskuju feces u analni kanal (autonomnim živčevljem); 6) slijede segmentalna stezanja sva tri dijela vanjskog sfinktera (dubokog, površnog pa potkožnog), koja će iz analnog kanala istisnuti sve zaostatke. Svrha rada. Trodimenzionalnim ultrazvukom prikazati analni kanal u zdravih žena te u onih koje pate od fekalne inkontinencije i rektokele, usporediti njihov unutrašnji i vanjski analni sfinkter. Metode. Analizirano je klinički i 3DUZ-om 40 pacijentica s fekalnom inkompetencijom i uspoređeno s 10 zdravih žena. Rezultat. Analni kanal je u zdravih žena zatvoren, njihov unutrapnji sfinkter je neoštećen. U žena s fekalnom inkompetencijom analni kanal je širok i otvoren te s razderanim sfinkterom. Zaključak. Unutarnji analni sfinkter je kolageno-mišićno tkivo oblika cilindra koje okružuje analni kanal, inerviran je alfa-simpatičkim živcima iz hipogastričkog pleksusa. Unutarnji sfinkter je okružen donjim dijelom vanjskog analnog sfinktera, koji je građen od prugastog mišićja inerviranog pudendalnim živcem. Njegovo oštećenje tijekom rađanja uzrokuje fekalnu inkontinenciju. Prepravak njegove razderane stijenke uspostavlja fekalnu kontinenciju

    KIRURŠKO LIJEČENJE STRES URINARNE INKONTINENCIJE, FEKALNE INKONTINENCIJE I VAGINALNOG PROLAPSA NOVOM OPERACIJOM »URETRO-ANO-VAGINOPLASTIKA«

    Get PDF
    We put forward a novel concept explaining the mechanism of micturition and the factors that control urinary continence. Also, we describe the mechanism of defecation and the factors that control stool continence and prevent fecal incontinence. A weak internal urethral sphincter (IUS) will not withstand sudden rise of intra-abdominal pressure and urine will leak. The weakness of the IUS is mostly due to traumatic rupture of its wall as a result of the huge vaginal distension that happens during prolonged, difficult and multiple frequent labors. So, surgical correction is by exposing that rupture and mending its walls. Also the marked vaginal distension which occurs in labor will cause lacerations in the internal anal sphincter (IAS) which is intimately related to the posterior vaginal wall. The torn weak IAS will cause fecal incontinence (FI). Exposing the torn IAS and mending the torn walls will restore the sphincter strength and fecal continence. Vaginal prolapse occurs as a result of vaginal wall weakness, redundancy and flabbiness subsequent to its marked stretching of its walls during vaginal deliveries. Overlapping the vaginal flaps both in the anterior and posterior vaginal wall, such repair will strengthen the vaginal walls, as if we put a collagenous mesh but instead this is an autologus collagenous mesh. We innovated an operation called »urethro-ano-vagino-plasty« to surgically treat urinary incontinence, fecal incontinence and and vaginal prolapse. Objectives. To describe this novel operation, and assess its results for a follow up period of 24 months. Methods. 134 patients with SUI and FI were assessed. Urethro-ano-vaginoplasty was done, and the results were assessed immediately and for 24 months follow up. Results. 121 (90.3%) gained urinary and fecal continence and remained continent in the follow up period. Conclusion. The internal anal sphincter (IAS) is a collageno-muscular tissue cylinder that surrounds the anal canal innervated by alpha-sympathetic nerve supply from the hypogastric nerves. It is surrounded in its lower part by the EAS which is a striated muscle innervated by the pudendal nerve. Its damage during childbirth causes fecal incontinence and mending the torn walls restores fecal continence.Predstavljena je nova koncepcija o mehanizmu mokrenja i čimbenicima koji reguliraju mokraćnu kontinenciju. Također, opisan je mehanizam defekacije te čimbenici koji kontroliraju kontinenciju stolice i sprječavaju fekalnu inkontinenciju. Slab unutarnji uretralni sfinkter (IUS) se ne može suprostaviti naglom porastu intraabdominalnog tlaka te će mokraća bježati. Slabost IUS-a je većinom posljedica ozljede njegove stijenke zbog silnog vaginalna širenja koje se zbiva tijekom produljenih, tešlih i učestalih rađanja. Kirurška korekcija se sastoji u nalaženju prsnuća i opskrbi njegove stijenke. Vaginalno širenje tijekom poroda uzrokuje prsnuće unutarnjeg analnog sfinktera (IAS), koji je intimno povezan sa stražnjom vaginalnom stijenkom. Oslabljeni i prsnuti IAS uzrokuje fekalnu inkontinenciju (FI). Prikaz prsnutog IAS-a i šivanje njegovih razderanih stijenki uspostavit će snagu sfinktera i fekalnu kontinenciju. Vaginalni prolaps nastaje kao posljedica slabosti i mlohavosti vaginalne stijenke te njene proširenosti, zbog istezanja tijekom vaginalnog rađanja. Preklapanjem vaginalnih režanja prednje i stražnje stijenke ojačava se stijenka, umjesto umjetne mrežice postavljamo vlastitu autolognu kolagenu mrežicu. Izumjeli smo za korekciju urinarne i fekalne inkontinencije te vaginalna prolapsa novu operaciju i nazcvali je »uretro-ano-vagino-plastika«. Cilj rada je opisati novu operaciju i prosuditi njen uspjeh nakon 24 mjeseca. Metoda. Operirane su 134 bolesnice sa stres urinarnom inkontinencijom i fekalnom inkontinencijom. Rezultati. 121 bolesnica (90,3%) je opet postigla mokraćnu i fekalnu kontinenciju i zadržala ih tijekom praćenja. Zaključak. Unutarnji analni sfinkter je kolegano-mišićni tkivni cilindar, inerviran alfa-simpatičnim živcima iz hipogastričkog pleksusa koji okružuje analni kanal. U donjem dijelu je okružen vanjskim sfinkterom koji je poprečno-prugaste mišićne građe i inerviran ograncima pudendalnog živca. Njegovo oštećenje tijekom rađanja uzrokuje fekalnu inkontinenciju, a šivanje prsnute stijenke uspostavlja fekalnu kontinenciju

    The ligational behavior of an isatinic quinolyl hydrazone towards copper(II)- ions

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The importance of the isatinic quinolyl hydrazones arises from incorporating the quinoline ring with the indole ring. Quinoline ring has therapeutic and biological activities whereas, the indole ring occurs in Jasmine flowers and Orange blossoms. As a ligand, the isatin moiety is potentially ambidentate and can coordinate the metal ions either through its lactam or lactim forms. In a previous study, the ligational behavior of a phenolic quinolyl hydrazone towards copper(II)- ions has been studied. As continuation of our interest, the present study is planned to check the ligational behavior of an isatinic quinolyl hydrazone.</p> <p>Results</p> <p>New homo- and heteroleptic copper(II)- complexes were obtained from the reaction of an isatinic quinolyl hydrazone (HL) with several copper(II)- salts <it>viz. </it>Clˉ, Brˉ, NO<sub>3</sub>ˉ, ClO<sub>4</sub><sup>-</sup>, SO<sub>4</sub><sup>2- </sup>and AcO<sup>-</sup>. The obtained complexes have O<sub>h</sub>, T<sub>d </sub>and D<sub>4h</sub>- symmetry and fulfill the strong coordinating ability of Clˉ, Brˉ, NO<sub>3</sub>ˉ and SO<sub>4</sub><sup>2- </sup>anions. Depending on the type of the anion, the ligand coordinates the copper(II)- ions either through its lactam (NO<sub>3</sub>ˉ and ClO<sub>4</sub><sup>-</sup>) or lactim (the others) forms.</p> <p>Conclusion</p> <p>The effect of anion for the same metal ion is obvious from either the geometry of the isolated complexes (O<sub>h</sub>, T<sub>d </sub>and D<sub>4h</sub>) or the various modes of bonding. Also, the obtained complexes fulfill the strong coordinating ability of Clˉ, Brˉ, NO<sub>3</sub>ˉ and SO<sub>4</sub><sup>2- </sup>anions in consistency with the donor ability of the anions. In case of copper(II)- acetate, a unique homoleptic complex (<b>5</b>) was obtained in which the AcO<sup>- </sup>anion acts as a base enough to quantitatively deprotonate the hydrazone. The isatinic hydrazone uses its lactim form in most complexes.</p

    Intraventricular Hemorrhage in Preterm Infants, Review Article

    Get PDF
    Intraventricular hemorrhage (IVH) or germinal matrix (GM) in other words, is a condition that can occur in premature births and can lead to long-term medical and developmental effects. While GM/IVH can happen in full-term infants, the hemorrhage in this group of infants is different from periventricular hemorrhage (PVH)/IVH in premature infants. Family members and caregivers of preterm infants and those at risk of preterm birth are confronted with two significant uncertainties concerning these newborns: Is the survival of this child likely? Will the child experience long-term sequelae, particularly developmental sequelae, if they survive? The significance of these questions lies in their potential to impact future medical decisions, including the level of intensity in the care provided. Infants born prematurely can suffer from various acquired lesions in the central nervous system (CNS), leading to long-term disability. These lesions include GM/IVH, periventricular white matter injury, hemorrhage, and diffuse injury to the developing brain. GM/IVH continues to be a major contributor to both illness and death in premature newborns.&nbsp; GM/IVH is primarily diagnosed by brain imaging techniques, typically cranial ultrasonography, as depicted below. Screening and serial examinations are essential for diagnosing GM/IVH, as it can occur without any noticeable clinical indications

    The ligational behavior of a phenolic quinolyl hydrazone towards copper(II)- ions

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The heterocyclic hydrazones constitute an important class of biologically active drug molecules. The hydrazones have also been used as herbicides, insecticides, nematocides, redenticides, and plant growth regulators as well as plasticizers and stabilizers for polymers. The importance of the phenolic quinolyl hydrazones arises from incorporating the quinoline ring with the phenolic compound; 2,4-dihydroxy benzaldehyde. Quinoline ring has therapeutic and biological activities whereas, phenols have antiseptic and disinfectants activities and are used in the preparation of dyes, bakelite and drugs. The present study is planned to check the effect of the counter anions on the type and geometry of the isolated copper(II)- complexes as well as the ligational behavior of the phenolic hydrazone; 4-[(2-(4,8-dimethylquinolin-2-yl)hydrazono)methyl] benzene-1,3-diol; (H<sub>2</sub>L).</p> <p>Results</p> <p>A phenolic quinolyl hydrazone (H<sub>2</sub>L) was allowed to react with various copper(II)- salts (Cl‾, Br‾, NO<sub>3</sub>‾, ClO<sub>4</sub>‾, AcO‾, SO<sub>4</sub><sup>2-</sup>). The reactions afforded dimeric complexes (ClO<sub>4</sub>‾, AcO‾ ), a binuclear complex (NO<sub>3</sub>‾ ) and mononuclear complexes (the others; Cl‾, Br‾, SO<sub>4</sub><sup>2-</sup>). The isolated copper(II)- complexes have octahedral, square pyramid and square planar geometries. Also, they reflect the strong coordinating ability of NO<sub>3</sub>‾, Cl‾, Br‾, AcO‾ and SO<sub>4</sub><sup>2- </sup>anions. Depending on the type of the anion, the ligand showed three different modes of bonding <it>viz</it>. (NN)<sup>0 </sup>for the mononuclear complexes (<b>3, 4, 6</b>), (NO)<sup>- </sup>with O- bridging for the dimeric complexes (<b>1, 5</b>) and a mixed mode [(NN)<sup>0 </sup>+ (NO)<sup>- </sup>with O- bridging] for the binuclear nitrato- complex (<b>2</b>).</p> <p>Conclusion</p> <p>The ligational behavior of the phenolic hydrazone (H<sub>2</sub>L) is highly affected by the type of the anion. The isolated copper(II)- complexes reflect the strong coordinating power of the SO<sub>4</sub><sup>2-</sup>, AcO‾, Br‾, Cl‾ and NO<sub>3</sub>‾ anions. Also, they reflect the structural diversity (octahedral, square pyramid and square planar) depending on the type of the counter anion.</p
    corecore