Time-Delayed Spread of Viruses in Growing Plaques

The spread of viruses in growing plaques predicted by classical models is greater than that measured experimentally. There is a widespread belief that this discrepancy is due to biological factors. Here we show that the observed speeds can be satisfactorily predicted by a purely physical model that takes into account the delay time due to virus reproduction inside infected cells. No free or adjustable parameters are used

Control d'il·luminació i ventilació d'un pàrquing

El treball presentat ve motivat per la necessitat d’instal•lació d’un pàrquing públic i privat de nova construcció a nivell d’il•luminació i ventilació. Per poder satisfer les necessitats del nostre client d’estalvi energètic i confort en l’edifici es decideix d’implementar una instal•lació immòtica que és l’aplicació de tècniques de gestió i control automatitzat a un edifici terciari amb bus de comunicació KNX/EIB. Per a la il•luminació s’han utilitzat fluorescents amb balasts DALI, que permeten la seva regulació i control, per així poder adequar en tot moment l’encesa i intensitat de llum d’aquests. En quant a la ventilació s’han utilitzat variadors de freqüència per també poder optimitzar el funcionament dels ventiladors podent posar-los en marxa quan realment sigui necessari i a la potència que calgui. Per enllaçar tots els elements de la instal•lació, detectors i actuadors, sorgeig la necessitat d’implementar xarxes de comunicació com el KNX/EIB, DALI, Modbus i Ethernet. Per gestionar variables, comunicacions i controlar elements, s´hi han implementen dos autòmats programables a més d’un PC integrat per la visualització i el control del pàrquing. S’ha aconseguit de realitzar un pàrquing totalment automàtic on no és necessaria l’actuació dels operaris i amb les principals càrregues elèctriques totalment regulables en potència. S’ha comprovat que la instal•lació funciona per sota de la potència nominal de les càrregues amb l’estalvi energètic que això suposa.

Supercritical CO2 recovery of caffeine from green coffee oil: new experimental solubility data and modeling

The caffeine solubility in supercritical CO2 was studied by assessing the effects of pressure and temperature on the extraction of green coffee oil (GCO). The Peng-Robinson¹ equation of state was used to correlate the solubility of caffeine with a thermodynamic model and two mixing rules were evaluated: the classical mixing rule of van der Waals with two adjustable parameters (PR-VDW) and a density dependent one, proposed by Mohamed and Holder² with two (PR-MH, two parameters adjusted to the attractive term) and three (PR-MH3 two parameters adjusted to the attractive and one to the repulsive term) adjustable parameters. The best results were obtained with the mixing rule of Mohamed and Holder² with three parameters.

Kuituvuoto reikäsihdillä massan syöttövaiheessa

Diplomityön tarkoituksena oli kehittää tutkimuslaite, jolla pystyttäisiin tutkimaan sellumassan syöttötapahtumaa reikäsihdillä ja tarkastelemaan syöttöhetkellä tapahtuvaa kuituhäviötä. Laitteen suunnittelun ja valmistuksen tavoitteena oli myös saada tutkimuslaite mahdollisim-man modifioitavaksi (syöttöaukon koko, muoto ja erityyppiset reikäsihdit ja näiden vaikutukset sellukuitujen hävikkiin). Haluttiin myös mahdollisuus syöttötapahtuman kuvaamiseen esim. suurnopeuskameroin, joka otettiinkin huomioon laiteosia valittaessa (läpinäkyvä akryyli). Tutkimuslaitteen kestävyyttä erilaisissa prosessiolosuhteissa haluttiin korostaa (voidaan operoida laajalla pH ja lämpötila-alueilla, sekä syöttöpainetta voidaan muunnella). Diplomityön kirjallisuusosassa käsitellään kuituvuodon aiheuttamia haittoja, joista tärkein on taloudellinen menetys. Näiden lisäksi kirjallisuusosassa tarkastellaan pääpirteittäin pesume-netelmiä ja käydään läpi kuitusulpun suotautumiseen vaikuttavia tekijöitä. Diplomityöhön sisältyi tutkimuslaitteen suunnittelun ja valmistuksen lisäksi myös laitteen toi-mivuuden testaus. Testit suoritettiin pohjoismaisella koivusellulla. Koivusellu otettiin happi-vaiheen jälkeisen pesurin poistosta. Massalle suoritettiin KAPPA-luvun, SR-luvun, viskositee-tin ja syrjäytys -määritykset, sekä kuituanalyysi. Laitteella suoritettiin 7 %, 10 % ja 12 % sakeuksisten massojen koeajotestit. Suodokset otettiin talteen jatkotutkimuksiin, jossa niistä mitattiin kuituvuoto. 10 % suodokselle suoritettiin myös kuituanalyysi. Tuloksista nähtiin, että 7 % sakeuksinen massa antoi lähes nelinkertaisen kuituvuotomäärän 10 % sakeuksiseen massan syöttöön nähden.

Modeling and simulation of forced-air cooling of strawberries using variable convective coefficient

In the forced-air cooling process of fruits occurs, besides the convective heat transfer, the mass transfer by evaporation. The energy need in the evaporation is taken from fruit that has its temperature lowered. In this study it has been proposed the use of empirical correlations for calculating the convective heat transfer coefficient as a function of surface temperature of the strawberry during the cooling process. The aim of this variation of the convective coefficient is to compensate the effect of evaporation in the heat transfer process. Linear and exponential correlations are tested, both with two adjustable parameters. The simulations are performed using experimental conditions reported in the literature for the cooling of strawberries. The results confirm the suitability of the proposed methodology.

Leiomioma do esôfago removido por videolaparoscopia

This report describes a leiomyoma of the inferior third section of the esophagus removed during laparoscopic cholecystectomy. The patient is a woman 55-years-age, carrying esophageal myoma of 40 mm in diameter wide, situated in the posterior wall of the lower esophagus. Indications for surgery were based mainly on the growth of the mass (6 mm when discovered 7 years previously, increased to 40 mm). Recently the patient returned suffering from pain, which could be attributed to his litiasic cholecystopaty. A small degree of low disphagia could also be observed. Radiologic imaging, direct endoscopic examination and endoscopic ultrasound showed that the mioma protruded on to the oesophagic lumen, discreetly diminishing there. A laparoscopic esophageal myomectomy was indicated at the same session of the laparoscopic cholecystectomy. Once the pneunoperitoneum was installed, five ports were placed as if for a hiatus hernia surgery. The cholecystectomy was uneventful. Next, an esophagoscopy was performed so as to determine the precise area covering the base of the tumour; at the right-lateral site. Longitudinal and circular fibres of the esophagus was severed over the lesion and the enucleation of the tumour was performed alternating the monopolar dissection, bipolar and hidrodisection. Control-endoscopy was carried out to verify mucosa integrity. Four suture points with poliglactine 3-0 string so as to close the musculature followed this. One suture was placed in for diminution of the size of the esophagean hiatus. Total time of intervention: two hours (30m for the cholecystectomy and one hour and thirty minutes for the myomectomy). Postoperative period: uneventful. Disappearance of the disphagia was observed. Radiologic transit control with water-soluble contrast at 4th post-operative day: good passage. Diagnosis from laboratory of pathology: conjunctive tumour formed by muscle non-striated cells: leiomyoma. The patient was re-examined on the two-month postoperative follow-up. General conditions were good and there were no complain of dysphagia. Neither there were any symptoms of gastro-esophageal reflux.

Fístula colecistogástrica

The authors report two cases of cholecistogastric fistula, both in female patients. These patients presented abdominal pain and dispeptic hipostenic syndrome, being diagnosed as calculous cholecistopathy. ln one patient, gastroduodenoscopy showed a fistula orifice in the stomach. ln the other case, the diagnosis was only made during the operation. The surgical procedure was cholecistectomy and gastric suture, with satisfatory postoperative evolution.

Leiomiomas do esôfago removidos por vídeo-toracoscopia

This report describes three cases of esophageal leiomyomas successfully resected by thoracoscopy. Surgical enucleation through minimally invasive surgery is the treatment of choice for esophageal leiomyoma. The conventional approach through a formal thoracotomy has the potential of causing excessive pain and patient discomfort. Moreover, the hospital stay and the recovery period are prolonged. Indications for surgery were based mainly on the size of the mass (<4 cm) and the presence of dysphagia. In one case there was a clear suspicion of malignancy. The tumour was located in the lower thoracic esophagus (case 1), in the middle thoracic esophagus (case 2) and in the upper esophagus (case 3). The CT was useful in identifying the relationship between the lesion and the organs of the mediastinum. The barium swallow study was able to locate the lesion along the esophagus. The endosonography determined the boundaries of the lesions. A right thoracoscopic approach was undertaken. Dissection of the esophagus around its entire perimeter was never necessary because all tumours were anterior or right sided. The tumours were better grasped with a traction suture than with forceps. The hidrodissection was very helpful. The water-soluble contrast swallow, performed on the fourth postoperative day, was normal. Clinical results were satisfactory in all patients. Biopsies should never be performed when the mucosa overlying is normal.

Hérnia diafragmática traumática crônica e fístula gastropleurocutânea

Traumatic diaphragmatic hernia is defined as a laceration of the diaphragm with an abdominal viscera herniation into the thorax. It is usually asymptomatic, with the exception of the cases with obstruction, strangulation, necrosis or perforation of the herniaded viscera. It is classified as acute, latent or chronic, in accordance with the evolutive period. At the latent phase, symptoms are indefinite and the radiological signals, which are suggestive of thoracic affections, are frequent and can induce a diagnosis error, leading to inadequate treatment.This article presents a case of chronic traumatic diaphragmatic hernia which was complicated by a gastricpleuralcutaneous fistula, due to an inadequate thoracic drainage. Considering that this is a chronic affection with an unquestionable surgical indication, due to the complications risk, it is essential to have a detailed diagnostic investigation, which aims at both avoiding an intempestive or inadequate therapeutics behaviour and reducing the affection morbimortality. Recently, the videolaparoscopic approach has proved to be more precise when compared to the other diagnostic methods, by direct visualization of the diaphragmatic laceration, allowing its correction by an immediate suture.

Siirtohinnoitteluperiaatteet johtamisen apuvälineenä: case-tutkimus

Tämä tutkimus tarkastelee siirtohinnoittelun periaatteita ja sen taustalla vaikuttavia tekijöitä. Tutkielman tavoitteena on tutkia kohdeyrityksen nykyistä siirtohinnoittelua ja laatia sille periaatteet sen yksiköiden väliselle sisäiselle kaupalle. Tarkoituksena on kehittää siirtohinnoitteluperiaatteet, jotka auttavat johtoa liiketoiminnan eteenpäin viemisessä niin, että nuo periaatteet ovat samalla oikeudenmukaiset kohdeyrityksen eri osapuolille. Tutkimus on luonteeltaan kvalitatiivinen, teoreettinen ja kuvaileva case-tutkimus. Se tuo esille teoriaosuudessa eri siirtohinnoitteluvaihtoehtoja ja pohtii analyyttisesti niiden hyötyjä ja haittoja. Teoriaosuus perustuu kattavalle kirjallisuudelle, jonka avulla otetaan huomioon tekijöitä, jotka vaikuttavat siirtohinnoitteluprosessin taustalla. Tutkielman empiirinen aineisto kerättiin haastattelemalla kohdeyrityksen ylintä johtoa. Haastatteluiden rakenne oli luonteeltaan puolistrukturoitu. Lisäksi käytiin aiheeseen liittyvää keskustelua useaan otteeseen kohde-yrityksen talouspäällikön kanssa sekä tehtiin tutustumiskäynti erääseen osuuskuntaan, jossa kohdeyritys on osakkaana. Vierailu perustui osuuskunnan talouspäällikön pitämään esitykseen ja sen aikana käytyyn keskusteluun. Haastattelut tehtiin kevään 2012 aikana. Tutkimuksen perusteella siirtohinnoittelu on monimutkainen prosessi, jossa samanaikaisesti ei voida saavuttaa kaikkia siltä vaadittuja tavoitteita. Siirtohinnoitteluperiaatteita laadittaessa tulee ottaa etenkin huomioon 1) organisaation liiketoiminnan luonne 2) yksiköiden luonne, 3) vaihdettavien tuotteiden luonne, 4) erilaisten hintojen saatavuus sekä 5) suorituskyvyn mittaus ja arviointi. Tämä tutkimus suosittelee kohdeyrityksen tulos-yksiköille yleisesti mukautetun markkinaperusteisen siirtohinnoittelu-vaihtoehdon käyttöönottoa. Jalostustoimintaa vaativien tuotteiden sisäiselle kaupalle tutkimus suosittelee kustannusperusteisen vaihtoehdon noudattamista.

Banda gástrica ajustável laparoscópica: alternativa técnica

In these paper we are presenting a technical alternative to laparoscopic adjustable gastric banding. From January 1999 to April 2000, 60 patients with mean body mass index (BMI) of 40,7 kg/m2 underwent laparoscopic adjustable gastric banding. The new technique is performed in two steps. In the first step, an isolation instrument (laparoscopic finger) is inserted through the lesser sac, next to the junction of diaphragmatic crura, including the lesser omentum in order to pull the band catheter. The second step separates the lesser omentum from the right side of the stomach.There was no mortality and the morbidity was 11,6% (1 slippage of the band and 6 trocar port seroma). The new technique was performed in all patients with no conversion to open procedure. We didn't have respiratory complications. This technical alternative is safe and easily performed, helping to prevent transoperative perforations.

Extração de fitobezoar gástrico por videolaparoscopia: considerações técnicas originais

Videolaparoscopic surgery has been used for treatment of almost all surgical abdominal diseases, mainly where there are no large ressections, or operative field is limited. In these situations, laparoscopic surgery has the advantages of less morbidity, quick recovery and good cosmetic results. Bezoars removal, or its mobilization, is probably included in these possible proceedings. Three non-laparotomic procedures were described: 1. endoscopic-laparoscopic; 2. videolaparoscopy and mobilization of intestinal bezoar to the cecum; 3. laparoscopy and gastrotomy for bezoar removal, through suprapubic incision or the umbilical punction. There have been only two publications describing the videolaparoscopic method for bezoar removal, and the methods applied can be complications or morbidity related. We describe one case where the applied technique is simple and easy to perform, time saving and probably less complications-related. This technique, with four trocars, utilized a plastic bag besides the stomach to be opened, followed by gastrotomy, bezoar removal and immediate introduction in the plastic bag, suture of gastrotomy and removal through the left subcostal trocar. This technique was feasible and easy to perform, with short operative time, and there were no intra or post-operative complications; the patient was discharged in the second post-operative day, and is without further problems after one year follow-up. We believe that this could be an adequate technique to perform laparoscopic gastric bezoar removal, and the rigid sequence of operative events allows a quick procedure, with minimal contamination. The videolaparoscopy seems to be an adequate access to surgical treatment of gastro-intestinal bezoars, with or without obstruction, and should be the ellected the procedure of choice to begin the surgical treatment, with convertion to laparotomy in case of any intra-operative adversity.

Suturas mecânicas

The authors review the use of staplers in General Surgery, mainly in Gastroenterological Surgery highlighting safety and effectiveness. They emphasize that the mechanic anastomosis are a viable technique and in some conditions, the best way to perform the anastomosis. The use of staplers makes surgery faster and easier and complications are, generally related to surgeon's experience in using them. Although its costs are higher compared to handsewn suture, it can make the patient total cost lower.

Anastomose esôfago-jejunal látero-lateral com grampeador linear cortante complementada por sutura manual

One of the most difficult procedures in digestive-tract surgery is esophago-jejunal anastomosis following total gastrectomy. Cost/benefit analysis of this procedure justifies the use of mechanical staplers, in spite of their high cost. A technical variant of the side-to-side esophago-jejunal anastomosis is presented, which incorporates the use of a cutting linear stapler. Technical maneuvers are easy to perform, the cost of the cutting linear stapler is smaller than the circular ones, the amplitude of the anastomosis is wider and the likelihood of fistulae is smaller when compared to other techniques. The side-to-side esophago-jejunal anastomosis with the cutting linear stapler is always complemented by a manual suture.

Complicação da banda gástrica ajustável videolaparoscópica para tratamento da obesidade mórbida: extrusão da banda

Various options for surgical treatment of morbid obesity have been developed with varying results: vertical banded gastroplasty with intestinal by-pass, disabsorptive surgeries and laparoscopic adjustable gastric banding. Although all of them have been effective in weight loss, lower rates of early and late postoperative complications have been described in some procedures. Laparoscopic adjustable silicone gastric banding (LASGB) has a similar principle as vertical banded gastroplasty and it is a minimally invasive procedure, with low systemic and operative problems, but not free of them. We report two rare cases of this complications of LASGB.