Total Factor Productivity and the Mongolian Transition

Total Factor Productivity (TFP)is often used on the macro-economic level as an indicator of changes in efficiency of a country. In many transition economies TFP is seen to have been negative the last decade of the plan economy and starts increasing and become positive after a (quite a) few years of transition. Many authors conclude that this is a gain in efficiency due to the structural changes –such as privatisation and liberalisation – carried out in order to establish a market economy in those countries. In the case of Mongolia, not only non-viable enterprises closed down, but many possibly viable enterprises with potential closed down as well. This raises the question whether changes in TFP were really attributable to increases in efficiency. To investigate this, the mathematical properties of TFP are analysed in order to generate new insights into the development of TFP in Mongolia. Simulations are performed to see what happens with TFP if not the le! ast efficient, but a certain percentage of enterprises in a (closed) economy randomly close down. The robustness of Total Factor Productivity of Mongolia was tested not only for errors in all estimated values but also for measurement errors in the data. It was concluded that in many commonly occurring cases it is not necessary to estimate alpha; that a random closure of enterprises fits the data of Mongolia much more closely than closing only the least efficient enterprises; and that measurement errors in the data influence the estimated TFP significantly

Answering attitudinal questions: modelling the response process underlying contrastive questions

We analyse reaction time distributions and responses for attitudinal survey questions, which were part of a self-administered questionnaire about medical and ethical issues. Two contrastive versions of each question were asked, whether an issue should be forbidden or whether the government should allow it. Logically, the answers to these contrastive questions should oppose, but numerous investigations have shown that they result in the so-called forbid/allow asymmetry : respondents tend to rather say ‘no’ to both questions. We present a mathematical model, based on point process theory, which formalises attitude representations in memory and different stages in the response process. The data of the allow questions are used for parameter estimation, while the forbid data are used to test the predictive power of different model versions. The result is a model that describes the cognitive processes underlying the asymmetry. It indicates that the forbid/allow asymmetry is caused by the use of an increased response threshold in forbid answers, and that the asymmetry size varies due to both respondent characteristics and the issue at hand. This model is capable of simultaneously predicting the asymmetry in the reaction time distributions and in the response scores for the answering categories. Copyright © 2007 John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55953/1/1337_ftp.pd

Suspended culture of <i>Ostrea edulis</i> in the Calich lagoon (North western Sardinia, Italy): preliminary results

Suspended culture is a widespread farming method used for many bivalve species such as mussels, oysters and scallops. In the Mediterranean, this technique is mainly practised in lagoons or in sheltered coastal areas using floating lines from which molluscs are suspended in several ways. In this study, the European flat oyster (Ostrea edulis Linné, 1758) was grown in suspended lantern nets in the Calich lagoon (Sardinia, Mediterranean Sea) from March 2004 to March 2005. Two distinct groups of 6 lanterns each were hung to longline ropes near the mouth (station 1) and in the central portion of the lagoon (station 2). In each lantern (diameter=50cm; height=30cm), 90 O. edulis specimens were grown and, in order to ensure good water circulation inside the lantern net, fouling organisms were removed every month. Overall mortality, shell length (anterior-posterior axis), shell width (maximum distance on the lateral axis, between both valves of the closed shell) and total wet weight of a 180 specimen oyster sample (30 from each lantern) were recorded every 2 months at each site. In addition, water temperature, salinity, dissolved oxygen, and pH were monitored monthly by means of a multi-parametric probe at both sites (between 10a.m. and 12p.m.). One-way ANOVA was used to test for differences in oyster final mean morphometric characters recorded at the 2 growing stations. Chi-square test (with Yates correction for continuity) was performed to compare survival rates at the end of the trial. From an initial mean shell length of 49.5±4.6mm, O. edulis growth rate showed a similar trend at both the stations. Nevertheless, ANOVA detected significant differences (F=7.10; p&lt;0.01) in final mean oyster length values (83.7±6.5mm at station 1 vs 81.7±7.6mm at station 2). Significant differences (F=9.74; p&lt;0.01) were also found in final mean oyster width (28.4±3.1mm at station 1 vs 27.5±2.8mm at station 2) and weight (F=4.00; p&lt;0.05) values (91.4±16.7g at station 1 vs 87.7±18.3g at station 2). Moreover, chi-square test revealed a significantly different survival rate (χ2=10.04; p&lt;0.01) between the 2 groups (57.4% at station 1 vs 47.6% at station 2).Water temperature, salinity, dissolved oxygen, and pH monthly values recorded at the 2 growing stations were almost identical. Thus, the observed differences in oyster growth and survival seemed not to be due to the hydrological variables considered. Instead, they could probably be related to mechanical and chemical effects of water renewal by coastal waters, which may have led to different seasonal seston food supplies at the 2 sites. The suspended culture of the European flat oyster described in this paper can increase the mollusc production of the Calich lagoon by growing a valuable bivalve species which is naturally scarce in this biotope. In fact, our preliminary results showed good survival and growth rates of O. edulis especially near the mouth of the lagoon. Furthermore, this farming technique could be a possible source of economic benefits for local fishermen and, above all, a low impact aquacultural activity compatible with the environment

Osservazioni sul regime alimentare di <i>Diplodus annularis</i> (Linnaeus, 1758) nello stagno di Calich (Sardegna nord occidentale) = Observations on the feeding behaviour of <i>Diplodus annularis</i> (Linnaeus, 1758) in the Calich Lagoon (North Western Sardinia)

Feeding behaviour of the annular sea bream Diplodus annularis was investigated in the Calich lagoon (NW Sardinia, Italy). The stomach contents of 130 adult specimens (TL=15.2±1.4 cm) collected in spring and summer 1998 were examined. Benthic fauna such as Mollusca, Amphipoda and Polychaeta were the main food items (23.4%, 18% and 5.7% respectively), but a large amount of detritus was also found (44%). Furthermore, significant differences in the diet of smaller and larger size classes were observed

<i>Thymus catharinae Camarda</i>: comparazione fitochimica della composizione dell'olio essenziale ottenuto da popolazioni puntuali vegetanti spontanee in Sardegna e valutazione della attività biologica

Sono stati intrapresi studi fitochimici al fine di descrivere compiutamente diverse popolazioni spontanee in Sardegna di Thymus catharinae. In diverse zone dell’interno della Sardegna, sono state effettuate raccolte puntuali della specie, al fine di verificare eventuali differenze fitochimiche legate al substrato, all’altitudine ed all’esposizione delle piante e infine valutarne l’attività antiradicalica ed antimicrobica

Predominance of null mutations in ataxia-telangiectasia

Ataxia-telangiectasia (A-T) is an autosomal recessive disorder involving cerebellar degeneration, immunodeficiency, chromosomal instability, radiosensitivity and cancer predisposition. The responsible gene, ATM, was recently identified by positional cloning and found to encode a putative 350 kDa protein with a PI 3-kinase-like domain, presumably involved in mediating cell cycle arrest in response to radiation-induced DNA damage. The nature and location of A-T mutations should provide insight into the function of the ATM protein and the molecular basis of this pleiotropic disease. Of 44 A-T mutations identified by us to date, 39 (89%) are expected to inactivate the ATM protein by truncating it, by abolishing correct initiation or termination of translation, or by deleting large segments. Additional mutations are four smaller in-frame deletions and insertions, and one substitution of a highly conserved amino acid at the PI 3-kinase domain. The emerging profile of mutations causing A-T is thus dominated by those expected to completely inactivate the ATM protein. ATM mutations with milder effects may result in phenotypes related, but not identical, to A-T

The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

AIM: The SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery. METHODS: This was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin. RESULTS: Overall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P < 0.001). After adjustment, delay was not associated with a lower rate of complete resection (OR 1.18, 95% CI 0.90-1.55, P = 0.224), which was consistent in elective patients only (OR 0.94, 95% CI 0.69-1.27, P = 0.672). Longer delays were not associated with poorer outcomes. CONCLUSION: One in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease

Global disparities in surgeons’ workloads, academic engagement and rest periods: the on-calL shIft fOr geNEral SurgeonS (LIONESS) study

: The workload of general surgeons is multifaceted, encompassing not only surgical procedures but also a myriad of other responsibilities. From April to May 2023, we conducted a CHERRIES-compliant internet-based survey analyzing clinical practice, academic engagement, and post-on-call rest. The questionnaire featured six sections with 35 questions. Statistical analysis used Chi-square tests, ANOVA, and logistic regression (SPSS® v. 28). The survey received a total of 1.046 responses (65.4%). Over 78.0% of responders came from Europe, 65.1% came from a general surgery unit; 92.8% of European and 87.5% of North American respondents were involved in research, compared to 71.7% in Africa. Europe led in publishing research studies (6.6 ± 8.6 yearly). Teaching involvement was high in North America (100%) and Africa (91.7%). Surgeons reported an average of 6.7 ± 4.9 on-call shifts per month, with European and North American surgeons experiencing 6.5 ± 4.9 and 7.8 ± 4.1 on-calls monthly, respectively. African surgeons had the highest on-call frequency (8.7 ± 6.1). Post-on-call, only 35.1% of respondents received a day off. Europeans were most likely (40%) to have a day off, while African surgeons were least likely (6.7%). On the adjusted multivariable analysis HDI (Human Development Index) (aOR 1.993) hospital capacity &gt; 400 beds (aOR 2.423), working in a specialty surgery unit (aOR 2.087), and making the on-call in-house (aOR 5.446), significantly predicted the likelihood of having a day off after an on-call shift. Our study revealed critical insights into the disparities in workload, access to research, and professional opportunities for surgeons across different continents, underscored by the HDI

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects