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A Model-Based Approach to Determine the Design Space of Preparative Chromatography

A dream of many pharmaceutical companies is to be able to register a large design space with the regulatory agencies. The problem is that this will require both time and money, so an intelligent method of validating a design space is needed. The design space should only cover operating points at which the process runs optimally. This means that the process should be optimized for different process

Compact fiber-optic fluorosensor using high-power continuous-wave violet diode laser

In this work a compact fluorosensor has been built for point-monitoring and imaging applications. The instrument has been applied in fluorescence studies on green vegetation and on malignant tissue. The instrument is based on a violet diode laser, an integrated spectrometer and optical fibers for light delivery and collection of the fluorescence signal. This combination makes the system very compa

Closure of atrial septal defect in the adult. Cardiac remodeling is an early event.

Background: Study aimed to describe the extent and the temporal profile of cardiac remodeling after atrial septal defect closure in the adult. Methods: Prospective and longitudinal echocardiographic assessment of right and left heart size before and after (1 day-1 week/1/4/12 months) surgical or catheter-based atrial septal closure in 39 adults (age 54 15 years). Results: Right ventricular and atr

Improving the rainbow attack by reusing colours

Hashing or encrypting a key or a password is a vital part in most network security protocols. The most practical generic attack on such schemes is a time memory trade-off attack. Such an attack inverts any one-way function using a trade-off between memory and execution time. Existing techniques include the Hellman attack and the rainbow attack, where the latter uses different reduction functions (

Production of external mycelium by ectomycorrhizal fungi in a Norway spruce forest was reduced in response to nitrogen fertilization

A field study was carried out to evaluate the influence of N fertilization on the growth of the external mycelium of ectomycorrhizal (EM) fungi in a Norway spruce forest in SW Sweden. Nylon mesh bags filled with sand were buried in the soil for 6-18 months and the ingrowth of mycelium was used as an estimate of EM mycelial growth. Root-isolated, trenched plots were used to estimate background grow

The role of advective fluid flow and diffusion during localized, solid-state dehydration: Sondrum Stenhuggeriet, Halmstad, SW Sweden

A localized dehydration zone, Sondrum stone quarry, Halmstad, SW Sweden, consists of a central, 1 m wide granitic pegmatoid dyke, on either side of which extends a 2.5-3 m wide dehydration zone (650-700 degrees C; 800 MPa; orthopyroxene-clinopyroxene-biotite-amphibole-garnet) overprinting a local migmatized granitic gneiss (amphibole-biotite-garnet). Whole-rock chemistry indicates that dehydration

Bounded positive solutions of Schrodinger equations

We prove under quite general assumptions the existence of a bounded positive solution to the semilinear Schrodinger equation in R-n, n greater than or equal to 3. (C) 2004 Elsevier Ltd. All rights reserved.

Improved approximation algorithms for optimization problems in graphs with superlogarithmic treewidth

In this paper we present two novel generic schemes for approximation algorithms for optimization NP-hard graph problems constrained to partial k-trees. Our first scheme yields deterministic polynomial-time algorithms achieving typically an approximation factor of k/log(1-is an element of)n, where k = polylog(n). The second scheme yields randomized polynomial-time algorithms achieving an approximat

Net portal absorption of enterally fed alpha-ketoglutarate is limited in young pigs

Our aim was to quantify the intestinal metabolic fate of dietary alpha-ketoglutarate (AKG). Female pigs In = 6; 21 d old) were implanted with arterial, venous, portal and gastric catheters and an ultrasonic portal flow probe and fed a corn and soybean meal-based diet. On (t)he day of the experiment, the pigs received a 4-h intragastric infusion of sodium AKG at a rate equivalent to 0, 2.5, 5 or 10

Adenoviral vectors for transient gene expression in human primitive hematopoietic cells: Applications and prospects.

The proliferation and differentiation of primitive hematopoietic cells is tightly controlled by a number of signaling pathways. Transient blockage or enhancement of these signaling pathways may provide a new approach to manipulate the proliferation and differentiation of primitive hematopoietic cells. Adenoviral vectors have in recent years emerged as powerful tools for transient gene expression i

TGF-beta receptor I conditional knockout mice develop spontaneous squamous cell carcinoma

We generated a mouse model with a conditional deletion of TGF-beta signaling in the neurons by crossing TGF-beta receptor I (T beta RI) floxed mice with neurofilament-H (NF-H) Cre mice. 35% of F1 conditional knockout (COKO) mice developed spontaneous squamous cell carcinomas (SCCs) in periorbital and/ or perianal regions. Transplantation of these tumors into athymic nude mice resulted in 62% tumor

Revealing signaling pathway deregulation by using gene expression signatures and regulatory motif analysis

Gene expression signatures consisting of tens to hundreds of genes have been found to be informative for different biological states. Recently, many computational methods have been proposed for biological interpretation of such signatures. However, there is a lack of methods for identifying cell signaling pathways whose deregulation result in an observed expression signature. We present a strategy

SclA, a novel collagen-like surface protein of Streptococcus pyogenes

Surface proteins of Streptococcus pyogenes are important virulence factors. Here we describe a novel collagen-like surface protein, designated SclA (streptococcal collagen-like surface protein). The sclA gene was identified in silico using the Streptococcal Genome Sequencing Project with the recently identified protein GRAB as the probe. SclA has a signal sequence and a cell wall attachment region