Development of Methods to Improve Lactose Recovery from Permeate and Drying Characteristics of Greek Acid Whey

Growth of higher protein dairy products and ingredients such as cheese, Greek yogurt, whey protein concentrates, and milk protein concentrates is limited by the amount of co-product generated and the ability to process them into value added ingredients. Finding value for all the co-products will help dairy industry to meet the growing demand for dairy protein products and ingredients. Commercial scale evaluation of new technologies for improving lactose crystallization and drying ability of Greek yogurt acid whey will help dairy industry to better utilize different dairy co-products. Commercially, lactose is manufactured from concentrated permeate by cooling and separating α-lactose monohydrate crystals. Factors that impact crystallization of lactose during cooling will influence the yield of lactose. Caking and powder stickiness are major challenges during drying of Greek yogurt acid whey or Greek acid whey (GAW), because of high acidity, high mineral concentration, and relatively low protein content in it. The first objective of this study was to evaluate commercial feasibility of using Soluble Soybean Polysaccharide (SSPS) to improve lactose recovery during manufacture of lactose from permeate. Previous research has demonstrated that lactose crystallization could be modified by using SSPS in pure lactose solutions. However, commercial lactose is typically manufactured by crystallization of concentrated permeate (CP). A laboratory scale crystallization set up with parallel crystallizers was utilized to conduct control and treatment experiments simultaneously. Lactose recovery with 0.1% SSPS addition was significantly (P \u3c 0.05) higher (76.31%) as compared to the control (71.33%). Out of the total SSPS added to the treatment solution, 79.82% was recovered into the wash water. The findings of this study suggest potential feasibility of SSPS for enhancing lactose crystallization during lactose manufacture from concentrated permeate. The objective of the second study was to evaluate commercial feasibility of using SSPS to improve the drying ability and powder characteristics of GAW. The composition of GAW is considerably different from that of cheese whey making it difficult to process into powder ingredients. The high lactic acid and mineral content in GAW delays lactose crystallization which causes stickiness during spray drying and caking during storage of the powder. The first study had shown that soluble soybean polysaccharide (SSPS) can enhance lactose crystallization in concentrated permeate. However, the effect of SSPS on the crystallization of lactose in concentrated GAW has not been evaluated. GAW obtained from a Greek yogurt manufacturer was vacuum concentrated to 56% total solids (30% Lactose) and crystallized using a laboratory scale crystallization tank. After crystallization, the concentrate was spray dried using a pilot scale NIRO dryer. GAW powder yield (51.87%) with 0.1% SSPS addition was significantly (P \u3c 0.05) higher compared to that of GAW without SSPS (44.51%) and observed to be less sticky on the dryer surface. The findings of this study indicate that SSPS can enhance lactose crystallization in concentrated GAW during crystallization, reduce the sticking of the caking of the GAW powder. The objective of the third study was to evaluate the feasibility of partial demineralization and deacidification of GAW by nanofiltration (NF) to improve the drying ability and powder characteristics of GAW. Greek yogurt acid whey (GAW) contains high concentrations of lactic acid (LA) and minerals as compared to cheese whey. The LA and the minerals, particularly the Calcium (Ca) in GAW cause stickiness during spray drying, thus limiting the processing and utilization of GAW. Nanofiltration (NF) has been in use to for partial removal of minerals from cheese whey and milk to produce high value-added dairy ingredients. Similarly, NF can potentially be applied for partial demineralization and deacidification of GAW to improve spray drying and powder properties. By NF processing, the lactic acid and total ash concentrations were reduced significantly (P \u3c 0.05) by 34.3±0.2 and 37.8±0.7, respectively. The reduction of monovalent ions, i.e., sodium and potassium were observed to be higher (66% and 62%) than that of calcium (41%). GAW-NFR powder yield (56.35%) was significantly (P \u3c 0.05) higher compared to that of GAW (44.51%) and observed to be less sticky on the dryer surface. The findings of this study indicate that partial demineralization and deacidification of GAW using NF can improve the spray drying characteristics of the GAW powder. The objective of the final study was to evaluate the effect of addition of SSPS to NFR-GAW on the drying characteristics of the GAW. In this study, the yield, and drying characteristics of GAW with and without 0.1% SSPS were compared. There was no significant (P \u3e 0.05) difference observed between the yields of GAW-NFR (56.35%) xvi and GAW-NFR with SSPS addition (58.24%). However, the yield of NFR-GAW (56.35%) was significantly (P \u3c 0.05) higher than that of GAW with SSPS addition (51.87%). From this study it can be concluded that there may not be any additional advantage in addition of SSPS to NFR-GAW in improving the spray drying characteristics of GAW

Hippocalcin Response to Calcium: Do Conserved Tryptophans – W30 or W103 – Matter?

Changes in intracellular calcium levels play a very important role in cell signaling, in turn, affecting neuronal functions such as memory, learning and cell death. A class of proteins called Neuronal Calcium Sensor (NCS) proteins serves to modulate the functioning of the neuronal cells in response to changes in calcium levels, and prevent neuronal apoptosis. Structurally, all NCS proteins have 4 calcium-binding EF hand motifs, although EF1 does not bind to calcium in many members. All NCS proteins have an acyl modification at the N- terminus – where a myristoyl group is added post-translationally. Hippocalcin (HPCA) is an NCS protein, and shares 95% similarity in primary amino acid sequence with another major NCS protein, Neurocalcin delta (NCALD). HPCA and NCALD have 2 evolutionary conserved tryptophan residues at the 30th, and 103rd amino acid position. Based on structural analyses and preliminary data, we propose that these tryptophan residues are important for the calcium- dependent changes in HPCA. Mutation of the residues even to “conserved substitution” (namely phenylalanine) appears to have drastic effects in NCALD. We propose that mutation of the W to F residues (individually or together) would have decreased response to calcium when compared with the native HPCA protein, and the effects will be similar in W to F NCALD mutants. Three different parameters will be used to compare the proteins’ response to calcium: (i) tryptophan fluorescence to monitor local changes in structure around the tryptophan residues, (ii) native gel electrophoresis to monitor global changes; and (iii) gel filtration chromatography to monitor the oligomerization state

Autonomous car driving with LIDAR

Tato bakalářská práce pojednává o autonomní jízdě modelu automobilu pomocí senzoru lidar. Může produkovat více dat za nejmenší dobu, což je hlavně detekce vzdáleností překážek kolem tohoto senzoru. Jedná se o jeden z užitečných senzorů pro autonomní řízení, protože jej lze implementovat z hlediska nákladů a pro účely dobré přesnosti. Zpočátku je lidar připojen k PC, pomocí aplikace RealTerm provedeme křížovou kontrolu, zda Lidar dává odpověď na znaky odeslané prostřednictvím této aplikace pomocí správné přenosové rychlosti (tj. 115200). Jakmile zkontrolujeme, zda lidar funguje správně, namontujeme lidar na model automobilu a napíšeme nezbytné příkazy v jazyce Arduino, abychom koordinovali čtení lidaru a směry modelu automobilu, abychom mohli manévrovat jeho pohyb. Jednoduchý nápad je zajistit, aby se auto zabránilo kolizi s okolím. To bude testováno v laboratoři za použití určité překážkové dráhy, aby se zkontrolovalo, zda lidar pomáhá zabránit kolizi automobilu. Pomocí tohoto konceptu se můžeme nesmírně rozvíjet také v oblasti autonomního řízení pro budoucí účely.This bachelor thesis is about the autonomous driving of a car model with the help of a lidar sensor device. It can produce multiple data in least amount of time which is mainly the detection of obstacles’ distances around this sensor. It is one of the useful sensors for autonomous driving as it can be implemented for cost effective and for good precision purposes. Initially the lidar is connected to the PC, by using the application RealTerm, we cross check if the Lidar gives response to the characters sent via this application using the correct baud rate (i.e. 115200). Once we check that the lidar is working properly, we mount the lidar on a car model and write the necessary commands in the Arduino language to coordinate the lidar readings and the directions of the car model in order to maneuver its motion. The simple idea is to make sure that the car avoids collision to its surrounding. This will be tested in the lab using certain obstacle course to check whether the lidar does help in avoiding the car from collision. Using this concept, we can also develop in the field of autonomous driving for the future purposes immensely

A Pragmatic Randomized Controlled Trial of 6-Step vs 3-Step Hand Hygiene Technique in Acute Hospital Care in the United Kingdom.

OBJECTIVE To evaluate the microbiologic effectiveness of the World Health Organization's 6-step and the Centers for Disease Control and Prevention's 3-step hand hygiene techniques using alcohol-based handrub. DESIGN A parallel group randomized controlled trial. SETTING An acute care inner-city teaching hospital (Glasgow). PARTICIPANTS Doctors (n=42) and nurses (n=78) undertaking direct patient care. INTERVENTION Random 1:1 allocation of the 6-step (n=60) or the 3-step (n=60) technique. RESULTS The 6-step technique was microbiologically more effective at reducing the median log10 bacterial count. The 6-step technique reduced the count from 3.28 CFU/mL (95% CI, 3.11-3.38 CFU/mL) to 2.58 CFU/mL (2.08-2.93 CFU/mL), whereas the 3-step reduced it from 3.08 CFU/mL (2.977-3.27 CFU/mL) to 2.88 CFU/mL (-2.58 to 3.15 CFU/mL) (P=.02). However, the 6-step technique did not increase the total hand coverage area (98.8% vs 99.0%, P=.15) and required 15% (95% CI, 6%-24%) more time (42.50 seconds vs 35.0 seconds, P=.002). Total hand coverage was not related to the reduction in bacterial count. CONCLUSIONS Two techniques for hand hygiene using alcohol-based handrub are promoted in international guidance, the 6-step by the World Health Organization and 3-step by the Centers for Disease Control and Prevention. The study provides the first evidence in a randomized controlled trial that the 6-step technique is superior, thus these international guidance documents should consider this evidence, as should healthcare organizations using the 3-step technique in practice. Infect Control Hosp Epidemiol 2016;37:661-666

The Effect of Soluble Soybean Polysaccharide Addition to Permeate Concentrate on Lactose Crystallisation, Growth and Recovery During Lactose Manufacturing

Lactose is manufactured from permeates of cheese whey, milk protein concentrate and a mix of both using a crystallisation process. Several factors, such as solute supersaturation, cooling rate and impurities, influence lactose crystallisation. This study focussed on the effect of soluble soybean polysaccharides (SSPS) on crystallisation during lactose manufacture from concentrated permeate solutions by evaluating lactose crystal growth and recovery with and without SSPS addition. Adding 0.1% (w/w) SSPS resulted in a significant difference (P \u3e 0.05) in lactose crystal size and yield. The results suggest that using SSPS during lactose manufacturing from permeate concentrates could influence lactose crystallisation and recover

Iron content of ferritin modulates its uptake by intestinal epithelium: implications for co-transport of prions

The spread of Chronic Wasting Disease (CWD) in the deer and elk population has caused serious public health concerns due to its potential to infect farm animals and humans. Like other prion disorders such a sporadic Creutzfeldt-Jakob-disease of humans and Mad Cow Disease of cattle, CWD is caused by PrP-scrapie (PrPSc), a β-sheet rich isoform of a normal cell surface glycoprotein, the prion protein (PrPC). Since PrPSc is sufficient to cause infection and neurotoxicity if ingested by a susceptible host, it is important to understand the mechanism by which it crosses the stringent epithelial cell barrier of the small intestine. Possible mechanisms include co-transport with ferritin in ingested food and uptake by dendritic cells. Since ferritin is ubiquitously expressed and shares considerable homology among species, co-transport of PrPSc with ferritin can result in cross-species spread with deleterious consequences. We have used a combination of in vitro and in vivo models of intestinal epithelial cell barrier to understand the role of ferritin in mediating PrPSc uptake and transport. In this report, we demonstrate that PrPSc and ferritin from CWD affected deer and elk brains and scrapie from sheep resist degradation by digestive enzymes, and are transcytosed across a tight monolayer of human epithelial cells with significant efficiency. Likewise, ferritin from hamster brains is taken up by mouse intestinal epithelial cells in vivo, indicating that uptake of ferritin is not limited by species differences as described for prions. More importantly, the iron content of ferritin determines its efficiency of uptake and transport by Caco-2 cells and mouse models, providing insight into the mechanism(s) of ferritin and PrPSc uptake by intestinal epithelial cells

Molecular, microbiological and clinical characterization of Clostridium difficile isolates from tertiary care hospitals in Colombia

In Colombia, the epidemiology and circulating genotypes of Clostridium difficile have not yet been described. Therefore, we molecularly characterized clinical isolates of C.difficile from patients with suspicion of C.difficile infection (CDI) in three tertiary care hospitals. C.difficile was isolated from stool samples by culture, the presence of A/B toxins were detected by enzyme immunoassay, cytotoxicity was tested by cell culture and the antimicrobial susceptibility determined. After DNA extraction, tcdA, tcdB and binary toxin (CDTa/CDTb) genes were detected by PCR, and PCR-ribotyping performed. From a total of 913 stool samples collected during 2013–2014, 775 were included in the study. The frequency of A/B toxins-positive samples was 9.7% (75/775). A total of 143 isolates of C.difficile were recovered from culture, 110 (76.9%) produced cytotoxic effect in cell culture, 100 (69.9%) were tcdA+/tcdB+, 11 (7.7%) tcdA-/tcdB+, 32 (22.4%) tcdA-/tcdB- and 25 (17.5%) CDTa+/CDTb+. From 37 ribotypes identified, ribotypes 591 (20%), 106 (9%) and 002 (7.9%) were the most prevalent; only one isolate corresponded to ribotype 027, four to ribotype 078 and four were new ribotypes (794,795, 804,805). All isolates were susceptible to vancomycin and metronidazole, while 85% and 7.7% were resistant to clindamycin and moxifloxacin, respectively. By multivariate analysis, significant risk factors associated to CDI were, staying in orthopedic service, exposure to third-generation cephalosporins and staying in an ICU before CDI symptoms; moreover, steroids showed to be a protector factor. These results revealed new C. difficile ribotypes and a high diversity profile circulating in Colombia different from those reported in America and European countries

Comparison of hemodynamic stability of propofol ketamine versus etomidate ketamine during induction in peritonitis cases posted for emergency surgery

The aim: The aim of the present study is to evaluate the hemodynamic stability of propofol ketamine versus etomidate ketamine during induction of anaesthesia in peritonitis cases posted for emergency surgery. Methods: Sixty patients with peritonitis, posted for emergency surgery under general anaesthesia, were randomly allocated to two groups. Group propofol ketamine (P + K) comprised of 30 patients (n=30) were induced with propofol 1 mg/kg and ketamine 0.75 mg/kg IV. Group etomidate ketamine (E + K) comprised 30 patients induced with etomidate 0.3 mg/kg and ketamine 0.75 mg/kg. The hemodynamic effects of the combination of the drugs in both groups were compared before and after induction. Results: The change in saturation (SPO2) and Heartrate between the groups P+K & group E+K before induction and after intubation was similar in both groups. There was a statistically insignificant fall in systolic blood pressure (SBP) and diastolic blood pressure (DBP), and mean arterial pressure (MAP) in group P+K before and after induction when compared to group E+K. Conclusions: The propofol ketamine and etomidate ketamine combinations have a similar haemodynamic profile and are equally effective in maintaining haemodynamic stability during induction and intubation

Defining the Vulnerable Period for Re-Establishment of Clostridium difficile Colonization after Treatment of C. difficile Infection with Oral Vancomycin or Metronidazole

Background:Clostridium difficile is an anaerobic, spore-forming bacterium that is the most common cause of healthcare-associated diarrhea in developed countries. A significant proportion of patients receiving oral vancomycin or metronidazole for treatment of Clostridium difficile infection (CDI) develop recurrences. However, the period of vulnerability to re-establishment of colonization by C. difficile after therapy is not well defined.Principal Findings:In a prospective study of CDI patients, we demonstrated that most vancomycin-treated patients maintained inhibitory concentrations of vancomycin in stool for 4 to 5 days after therapy, whereas metronidazole was only detectable during therapy. From the time of elimination of the antibiotics to 14 to 21 days after therapy, a majority of stool suspensions supported growth of C. difficile and deep 16S rRNA sequencing demonstrated persistent marked alteration of the indigenous microbiota. By 21 to 28 days after completion of CDI treatment, a majority of stool suspensions inhibited growth of C. difficile and there was evidence of some recovery of the microbiota.Conclusions:These data demonstrate that there is a vulnerable period for re-establishment of C. difficile colonization after CDI treatment that begins within a few days after discontinuation of treatment and extends for about 3 weeks in most patients

Reliability of MR Enterography Features for Describing Fibrostenosing Crohn Disease

BACKGROUND: Clinical decision making and drug development for fibrostenosing Crohn disease is constrained by a lack of imaging definitions, scoring conventions, and validated end points. PURPOSE: To assess the reliability of MR enterography features to describe Crohn disease strictures and determine correlation with stricture severity