5,208 research outputs found
On the impact of the TFP growth on the employment rate: does training on-the-job matter?
TFP growth, unemployment, training, human capital depreciation, capitalization, creative destruction effect
The impact of technological and organizatioanl changes on labor flows. Evidence on French establishments
This paper investigates the effect of organizational and technological changes on job stability of different occupations in France. We first develop a basic matching model with endogenous job destsruction. It provides a structure to the empirical analysis, where we extensively exploit a unique data set on a representative sample of French establishments. The adoption of information technologies is positively correlated to labor flows of blue collar workers while most of the new workplace organizational practices positively influence the managers’ turnover.
Low-Skilled Unemployment, Capital-Skill Complementarity and Embodied Technical Progress
We construct an intertemporal general equilibrium model with two types of jobs and two types of workers. We allow for job competition between high- and low-skilled segment of the labour market and for on-the-job search. Matching processes are represented by matching functions à la Pissarides. Workers search intensities are endogenous. Biased technological change is introduced via embodied technical progress and a capital-skill complementarity. The model is calibrated and simulated to evaluate the impact of various types of shocks. The model reproduces quite well the unemployment rate changes and the relative wage stability observed over the last two decades. It suggests strong interactions between biased technological change, discouragement effects and job competition.Skill mismatch; equilibrium unemployment; ladder effect; macro dynamics
Identification of new protein-protein interactions with NUAK2 by proximity-dependent biotin labeling
In this Master’s project, I have studied a mammalian serine-threonine kinase NUAK2 implicated in human disease but whose molecular functions and interacting proteins are as of yet poorly characterized. The goal was to identify new interacting proteins to increase understanding of the molecular functions and potentially link to human physiology and disease. Recent work from the host lab shows NUAK2 loss in cultured primary cells mimics loss of the tumor suppressor LKB1 which also acts upstream of NUAK2, together suggesting NUAK2 could be involved in tumor suppression.
Currently, only two protein-protein interacting proteins with NUAK2 have been identified: NUAK2 is targeted to actin stress fibers by the myosin phosphatase Rho-interacting protein (MRIP), and it is involved in regulating cell contractility by affecting indirectly the phosphorylation cycle of the myosin light chain through inactivation of the myosin phosphatase target subunit 1 (MYPT1).
In this project, I utilized a novel protein-protein interaction screening method that utilizes proximity-dependent biotin labeling to identify new interacting proteins with NUAK2 in human embryonic kidney cells (HEK 293). This method is based on fusing an E.Coli promiscuous biotin ligase, BirA*(R118G), to the investigated protein. The BirA*(R118G) ligase biotinylates all the proteins in close proximity of the fusion protein creating a history of protein-protein associations over time. Afterwards, the biotinylated proteins can be isolated by affinity purification methods and identified by mass-spectrometry.
The screening identified the previously known interaction partners of NUAK2 indicating it was technically successful. In addition, I also identified in total 108 novel potential protein interaction partners for NUAK2. One of the top hits was Cytospin-A, a cross-linking protein between microtubules and actin cytoskeleton, supporting a role of NUAK2 as regulator of cytoskeleton. Supporting the validity of our finding, Cytospin-A depletion in mammalian cells causes defective actin-cytoskeleton reorganization, a very similar phenotype seen with NUAK2 depletion.
In future studies, I will continue to investigate the specific role of NUAK2 and Cytospin-A aiming for detailed information on the function of NUAK2 in regulation of microtubules and actin cytoskeleton. Validation of some of the other identified interactions is expected to provide novel insights to the biology and role of NUAK2 in LKB1 tumor suppressor functions
AIP and MEN1 mutations and AIP immunohistochemistry in pituitary adenomas in a tertiary referral center.
Background: Pituitary adenomas have a high disease burden due to tumor growth/
invasion and disordered hormonal secretion. Germline mutations in genes such as MEN1
and AIP are associated with early onset of aggressive pituitary adenomas that can be
resistant to medical therapy.
Aims: We performed a retrospective screening study using published risk criteria to
assess the frequency of AIP and MEN1 mutations in pituitary adenoma patients in a
tertiary referral center.
Methods: Pituitary adenoma patients with pediatric/adolescent onset, macroadenomas
occurring ≤30 years of age, familial isolated pituitary adenoma (FIPA) kindreds and
acromegaly or prolactinoma cases that were uncontrolled by medical therapy were
studied genetically. We also assessed whether immunohistochemical staining for
AIP (AIP-IHC) in somatotropinomas was associated with somatostatin analogs (SSA)
response.
Results: Fifty-five patients met the study criteria and underwent genetic screening for
AIP/MEN1 mutations. No mutations were identified and large deletions/duplications were
ruled out using MLPA. In a cohort of sporadic somatotropinomas, low AIP-IHC tumors
were significantly larger (P = 0.002) and were more frequently sparsely granulated
(P = 0.046) than high AIP-IHC tumors. No significant relationship between AIP-IHC and
SSA responses was seen.
Conclusions: Germline mutations in AIP/MEN1 in pituitary adenoma patients are rare and
the use of general risk criteria did not identify cases in a large tertiary-referral setting.
In acromegaly, low AIP-IHC was related to larger tumor size and more frequent sparsely
granulated subtype but no relationship with SSA responsiveness was seen. The genetics
of pituitary adenomas remains largely unexplained and AIP screening criteria could be
significantly refined to focus on large, aggressive tumors in young patients
Unemployment and Endogenous Growth with Capital-Skill Complementarity
We construct an endogenous growth intertemporal general equilibrium model with two types of jobs and two types of workers. We allow for job competition between high- and low skilled workers on the low-skilled segment of the labor market and for on-the-job search for high skilled workers. Matching processes are represented by matching functions à la Pissarides. Workers search intensities are endogenous. We distinguish between embodied and disembodied technological progress and endogenize them through a learning by doing process based on capital accumulation. Social returns to capital are imposed to be constant. Biased technological change is introduced via embodied technical progress and new technologies-skill complementarity relationship. The model reproduces quite well the producivity slowdown puzzle, the unemployment rate evolutions and the relative wage stability observed over the last decades. It suggests strong interactions between embodied technological progress, biased technological change, discouragement effects on job competition.skill mismatch, equilibrium unemployment, ladder effect, macro dynamics, endogneous growth, productivity slowdown, learning by doing
Technological and organizational changes, and labor flows: evidence on French establishments
This paper investigates the effects of organizational and technological changes on job stability of different occupational categories in France. We conduct an empirical analysis in which we make extensive use of a unique data set on a representative sample of French establishments. Working with various indicators of labor flows (gross labor flows, hiring rate, firing rate, net labor flows and churning flows), we find that the use of new technology seems to have a positive effect on aggregate job turnover and, more specifically, turnover among manual workers. In contrast, innovative workplace organizational practices are related to lower turnover among clerical workers and intermediate professionals and have a positive effect on churning among manager
Does the growth process discriminate against older workers?
This paper seeks to gain insights on the relationship between growth and unemployment, when considering heterogeneous agents in terms of age. We introduce life cycle features in the endogenous job destruction framework à la Mortensen and Pissarides (1998). We show that, under the assumption of homogeneous productivity among workers, firms tend to fire older workers more often than young ones, when deciding whether to update or not a technology: there is an equilibrium where the creative destruction effect dominates over the capitalization effect for old workers, whereas the capitalization effect dominates for young workers. This discrimination against older workers can be moderated when we introduce heterogeneity (in terms of productivity) among workers. We also provide empirical support for these theoretical findings using OECD panel data and numerical simulations of the model
Optimization of a portable NIR device for the optical supervision of milk coagulation process
The coagulation of milk is the fundamental process in cheese-making, which is based on a gel formation as consequence of physicochemical changes taking place in the casein micelles. Monitoring the whole process of milk curd formation is a dedicated process for dairy researchers and cheese companies. In addition to advances in composition-based applications by means of NIR spectroscopy, researchers are pursuing dynamic applications that show promise especially with regard to tracking a sample in situ during processing The objective of this work is to propose an original portable NIR equipment to supervise the milk coagulation process. The experiments have been carried out on sheep and goat milk, by immersion of the probe directly in the liquid and acquiring spectrum each 1 minute during the 30 minutes of coagulation process. The increasing values of transflected light registered allow identifying, based on PCA analysis, the different kinetics that occur along the gel formation and the time to reach the optimal gel firmness to cut the cur
- …