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FOR PH.D.S on the job market in the sciences, no element of the hiring process is more important for making or breaking your prospects than the job talk. At some [...]

ABSTRACTIn 1970, two clinicians, McEvedy and Beard [McEvedy CP, Beard AW (1970) Royal Free Epidemic of 1955: A Reconsideration The British Medical Journal 1: No. 5687: 7-11] re-analysed some of the case notes, and hypothesised that the Royal Free outbreak was epidemic hysteria. This hypothesis was the beginning of an entrenched belief that the disease at the Royal Free, and similar cluster outbreaks, were psychosomatic. This was to have a profound effect on the interpretation of the same illness for nearly 50 years as a presumptive psychosomatic, an interpretation that has lasted nearly 50 years. Methods:The 1927 Susceptible Infected Recovered (SIR) mathematical model [Kermack WO, McKendrick AG. Contribution to the mathematical theory of epidemics. Proc Royal Soc London. 1927;772:701–721] for the transmission of disease has been used to examine the published admission data from the Royal Free Hospital. for the purpose of finding out if the disease had the characteristics of a contagious disease. Similar cluster outbreaks have also been modelled to assess whether they have similar characteristics to the Royal Free outbreak. Results:Using the 1927 Susceptible Infected Recovered (SIR) model [Kermack WO, McKendrick AG. Contribution to the mathematical theory of epidemics. Proc Royal Soc London. 1927;772:701–721] for the transmission of disease, we show that the epidemic of a disease of an unknown aetiology at the Royal Free Hospital in 1955, and other similar twentieth-century outbreaks, have the characteristics of a communicable disease. The disease causing the Royal Free outbreak was given the name ‘Benign Myalgic Encephalomyelitis' by Acheson [A new clinical entity? Lancet. 1956;1:789–790] in 1956, now identified as ME. Conclusions:By showing that the Royal Free and other ME attributed outbreaks fit the SIR disease model, we demonstrate that the McEvedy and Beard hysteria hypothesis is mathematically incorrect. The ensuing management of the treatment of ME/CFS-like conditions evolving from that, now mathematically improbable belief may need to be re-evaluated.

One-third of all protein-coding genes from bacterial genomes cannot be annotated with a function. Here, to investigate the functions of these genes, we present genome-wide mutant fitness data from 32 diverse bacteria across dozens of growth conditions. We identified mutant phenotypes for 11,779 protein-coding genes that had not been annotated with a specific function. Many genes could be associated with a specific condition because the gene affected fitness only in that condition, or with another gene in the same bacterium because they had similar mutant phenotypes. Of the poorly annotated genes, 2,316 had associations that have high confidence because they are conserved in other bacteria. By combining these conserved associations with comparative genomics, we identified putative DNA repair proteins; in addition, we propose specific functions for poorly annotated enzymes and transporters and for uncharacterized protein families. Our study demonstrates the scalability of microbial genetics and its utility for improving gene annotations.

We present new total intensity and linear polarization VLBA observations of the $\nu=2$and $\nu=1$$J=1{-}0$maser transitions of SiO at 42.8 and 43.1 GHz in a number of Mira variable stars over a substantial fraction of their pulsation periods. These observations were part of an observing program that also includes interferometric measurements at 2.2 and 3.6 micron [CITE]; comparison of the results from different wavelengths allows studying the envelope independently of the poorly known distances to these stars. Nine stars were observed at from one to four epochs during 2001. The SiO emission is largely confined to rings which are smaller than the inner radius of the dust shells reported by [CITE]. Two stars (U Orionis, R Aquarii) have maser rings with diameters corresponding to the size of the hot molecular layer as measured at 3.6 micron; in the other cases, the SiO rings are substantially larger. Variations of ring diameter for most, but not all stars, had an rms amplitude in agreement with the models of [CITE] although the expected relationship between the diameter and pulsation phase was not seen. The ring diameter in U Orionis shows remarkably small variation. A correlation between the 2.2/3.6 μm diameter ratio with that of the SiO/3.6 μm diameter ratio is likely due to differences in the opacities at 2.2 and 3.6 μm in a molecular layer. A further correlation with the inner size of the dust shell reported by [CITE] suggest some differences in the temperature structure. Clear evidence is seen in R Aquarii for an equatorial disk similar to that reported by [CITE]; rotation is possibly also detected in S Coronae Boralis.

ABSTRACTSerotyping of Salmonellahas been an invaluable subtyping method for epidemiologic studies for more than 70 years. The technical difficulties of serotyping, primarily in antiserum production and quality control, can be overcome with modern molecular methods. We developed a DNA-based assay targeting the genes encoding the flagellar antigens (fliCand fljB) of the Kauffmann-White serotyping scheme. Fifteen H antigens (H:a, -b, -c, -d, -d/j, -e,h, -i, -k, -r, -y, -z, -z10, -z29, -z35, and -z6), 5 complex major antigens (H:G, -EN, -Z4, -1, and -L) and 16 complex secondary antigens (H:2, -5, -6, -7, -f, -m/g,m, -m/m,t, -p, -s, -t/m,t, -v, -x, -z15, -z24, -z28, and -z51) were targeted in the assay. DNA probes targeting these antigens were designed and evaluated on 500 isolates tested in parallel with traditional serotyping methods. The assay correctly identified 461 (92.2%) isolates based on the 36 antigens detected in the assay. Among the isolates considered correctly identified, 47 (9.4%) were partially serotyped because probes corresponding to some antigens in the strains were not in the assay, and 13 (2.6%) were monophasic or nonmotile strains that possessed flagellar antigen genes that were not expressed but were detected in the assay. The 39 (7.8%) strains that were not correctly identified possessed an antigen that should have been detected by the assay but was not. Apparent false-negative results may be attributed to allelic divergence. The molecular assay provided results that paralleled traditional methods with a much greater throughput, while maintaining the integrity of the Kauffmann-White serotyping scheme, thus providing backwards-compatible epidemiologic data. This assay should greatly enhance the ability of clinical and public health laboratories to serotype Salmonella.

We have analysed near-infrared NTT/SofI observations of the starburst cluster Westerlund 1, which is among the most massive young clusters in the Milky Way. A comparison of colour-magnitude diagrams with theoretical main-sequence and pre-main sequence evolutionary tracks yields improved extinction and distance estimates of AKs= 1.13 ? 0.03?mag and d = 3.55 ? 0.17?kpc (DM = 12.75 ? 0.10?mag). The pre-main sequence population is best fit by a Palla & Stahler isochrone for an age of 3.2?Myr, while the main sequence population is in agreement with a cluster age of 3 to 5?Myr. An analysis of the structural parameters of the cluster yields that the half-mass radius of the cluster population increases towards lower mass, indicative of the presence of mass segregation. The cluster is clearly elongated with an eccentricity of 0.20 for stars with masses between 10 and 32?M?, and 0.15 for stars with masses in the range 3 to 10?M?. We derive the slope of the stellar mass function for stars with masses between 3.4 and 27?M?. In an annulus with radii between 0.75 and 1.5?pc from the cluster centre, we obtain a slope of ? = -1.3. Closer in, the mass function of Westerlund 1 is shallower with ? = -0.6. The extrapolation of the mass function for stars with masses from 0.08 to 120?M?yields an initial total stellar mass of ?52?000?M?, and a present-day mass of 20?000 to 45?000?M?(about 10 times the stellar mass of the Orion nebula cluster, and 2 to 4 times the mass of the NGC 3603 young cluster), indicating that Westerlund?1 is the most massive starburst cluster identified to date in the Milky Way.

Observations of extrasolar planets using integral field spectroscopy (IFS), if coupled with an extreme adaptive optics system and analyzed with a simultaneous differential imaging technique (SDI), serve as a powerful tool for directly detecting and characterizing extrasolar planets; they enhance the signal of the planet and at the same time reduce the impact of stellar light and, consequently, important noise sources, such as speckles. In order to verify the efficiency of such a technique, we have developed a simulation code that is able to test the capabilities of this IFS-SDI technique for different kinds of planets and telescopes by modeling the atmospheric and instrumental noise sources. The first results obtained with the simulations show that many significant extrasolar planet detections are indeed possible using the present 8 m class telescopes within a few hours of exposure time. The procedure that is adopted to simulate IFS observations is presented here in detail, where we explain in particular how we obtain estimates of the speckle noise, adaptive optics corrections, specific instrumental features, and how we test the efficiency of the SDI technique in order to increase the signal-to-noise ratio of the planet detection. The most important results achieved from simulations of various objects, from 1 MJobjects to 30 MJbrown dwarfs, and for observations with an 8 m telescope, are then presented and discussed.

Chromatography plays a vital role in supporting preclinical pharmaceutical development, whether in providing assays for purity determinations, preparative separation of small amounts of intermediates for route selection studies, or purification of bulk drug substances on multikilogram scale. All three approaches are illustrated in the recent development of a candidate HIV protease inhibitor in these laboratories. Chiral supercritical fluid chromatography (SFC) on the hundreds-of-milligrams scale afforded an enantiopure intermediate to facilitate early synthetic studies, HPLC on the tens-of-grams scale provided purified material for use in salt form investigations, and HPLC using a 30 cm column was used to purify 5.6 kg of a key intermediate to provide material for early preclinical evaluations.

We investigated the response of chronic neck and shoulder pain to decompression of the carpal tunnel in 38 patients with whiplash injury. We also determined the plasma levels of substance P (SP) and calcitonin gene-related peptide (CGRP), which are inflammatory peptides that sensitise nociceptors. Compared with normal control subjects, the mean concentrations of SP (220 v28 ng/l; p < 0.0001) and CGRP (400 v85 ng/l; p < 0.0005) were high in patients with chronic shoulder and neck pain before surgery. After operation their levels fell to normal. There was resolution of neurological symptoms with improvement of pain in 90% of patients. Only two of the 30 with chronic neck and shoulder pain who had been treated conservatively showed improvement when followed up at two years.In spite of having neuropathic pain arising from the median nerve, all these patients had normal electromyographic and nerve-conduction studies. Chronic pain in whiplash injury may be caused by ‘atypical’ carpal tunnel syndrome and responds favourably to surgery which is indicated in patients with neck, shoulder and arm pain but not in those with mild symptoms in the hand. Previously, the presence of persistent neurological symptoms has been accepted as a sign of a poor outcome after a whiplash injury, but our study suggests that it may be possible to treat chronic pain by carpal tunnel decompression.

RAD26, the yeast homologue of human CSB, has an essential role in transcription-coupled repair (TCR). We have mapped the requisite of Rad26 for nucleotide excision repair (NER) within the different regions of the yeast Saccharomyces cerevisiae MFA2 gene at nucleotide resolution. Our results show that Rad26 is dispensable for enhanced NER in both the MFA2 upstream promoter, except in the TATA box region, and for enhanced NER in both strands of the active gene at a site close to the transcription termination region. As expected, it is not needed for repair of regions downstream of where transcription terminates. However, it is required for TCR in the transcription initiation and elongation regions. Our data support the hypothesis that Rad26 is required for the interchange between holo-TFIIH and a putative repairosome containing core TFIIH and other NER proteins. Close to the end of transcription, hotspots for the repair of CPDs in both the transcribed strand and the non-transcribed strand occur. This enhanced repair is independent of Rad26. Hence, TFIIH may take a form favourable for forming a repairosome without Rad26 assistance; here the organisation of the DNA during the termination of transcription may facilitate access of a repair complex to enable enhanced repair of both strands.

A system is described for mapping oxidative DNA damage (sites sensitive to formamidopyrimidine-DNA glycosylase and single-strand breaks) at nucleotide resolution in the nuclear and mitochondrial DNA of Saccharomyces cerevisiae. Our 3' end labelling method is sensitive and was first developed using the well-studied inducer of oxidative DNA damage, methylene blue (MB) plus light. We treated yeast DNA in vitro with this so as to maximise levels of damage for assay development. Unfortunately, MB does not remain in yeast cells and yeast DNA repair mutants sensitive to active oxygen species are not sensitive to this agent, thus for in vivo experiments we turned to a polycyclic aromatic, RO 19-8022 (RO). This resulted in oxidative DNA damage when light was applied to yeast cells in its presence. The spectra of enzyme-sensitive sites and single-strand breaks induced by MB in vitro or by RO plus light in vivo or in vitro were examined in two yeast reporter genes: the nuclear MFA2 and the mitochondrial OLI1. The experiments revealed that most of the enzyme-sensitive sites and single-strand breaks induced by MB or RO plus light are at the same positions in these sequences, and that these are guanines.

The bifunctional alkylating anticancer drug nitrogen mustard forms a variety of DNA lesions, including monoadducts and intrastrand and interstrand crosslinks. Although it is known that nucleotide excision repair (NER) is important in processing these adducts, the role of the other principal excision repair pathway, base excision repair (BER) is less well defined. Using isogenic Saccharomyces cerevisiae strains disrupted for a variety of NER and BER genes we have examined the relative importance of the two pathways in the repair of nitrogen mustard adducts. As expected, NER defective cells (rad4 and rad14 strains) are extremely sensitive to the drug. One of the BER mutants, a 3-methyladenine glycosylase defective (mag1) strain also shows significant hypersensitivity. Using a rad4/mag1 double mutant it is shown that the two excision repair pathways are epistatic to each other for nitrogen mustard sensitivity. Furthermore, both rad14 and mag1 disruptants show elevated levels of nitrogen mustard-induced forward mutation. Measurements of repair rates of nitrogen mustard N-alkylpurine adducts in the highly transcribed RPB2 gene demonstrate defects in the processing of mono-adducts in rad4, rad14 and mag1 strains. However, there are differences in the kinetics of adduct removal in the NER mutants compared to the mag1 strain. In the mag1 strain significant repair occurs within 1 h with evidence of enhanced repair on the transcribed strand. Adducts however accumulate at later times in this strain. In contrast, in the NER mutants repair is only evident at times greater than 1 h. In a mag1/rad4 double mutant damage accumulates with no evidence of repair. Comparison of the rates of repair in this gene with those in a different genomic region indicate that the contributions of NER and BER to the repair of nitrogen mustard adducts may not be the same genome wide.

Abstract: The physiological representation of the shoulder and surrounding body was examined in layer IV of somatosensory cortex (SI) in rats that had underground removal of the forelimb, either as newborns on postnatal day three (PND-3) or as adults (at least 8 weeks of age). Electrophysiological recordings were used to map the shoulder and body representations (physiological map), and the mitochondria marker, cytochrome oxidase (CO), was used to visualize recording sites in barrel and barrel-like structures (morphological map) in layer IV of deafferents and intact controls. The SI shoulder representation lies in a nebulously stained region that lies posterior to the forearm, wrist, and forepaw representations; the latter region is associated with the well-defined forepaw barrel subfield (FBS). The major findings are: (1) the shoulder is represented as a single zone located at the posterior extent of the SI body map in intact rats; (2) limb deafferentation in adult or neonatal rats that were physiologically mapped 6–16 weeks post-amputation resulted in two or more islets of ”new” representation of the shoulder in the FBS in addition to the representation of the ”original” shoulder in the posterior part of the body map; (3) deafferentations made in neonatal rats, physiologically mapped as adults, had a significantly greater (Mann-Whitney U) amount of ”new” cortical representation within the FBS than did rats deafferented as adults; (4) fewer unresponsive sites in the FBS were found for neonate deafferents than for adult deafferents; (5) evoked response latencies following electrical stimulation of the shoulder were shortest for cortical sites within the ”original” shoulder representation in intact controls, and latencies recorded at the ”original” shoulder representation in deafferents were also shorter than latencies recorded in ”new” shoulder representations in both groups of deafferents; and (6) morphological maps of the FBS were altered in neonate deafferents to the extent that the barrel structure was poorly formed, as exemplified by the absence of the four mediolateral running bands; however, the overall ovoid shape of the FBS was still apparent, but not as sharply defined as for intact controls or adult deafferents. Possible mechanisms for reorganization following large-scale deafferentation are discussed.

According to the United Kingdom's Charities Aid Foundation, charities are suffering during this recession with decreased donations and increased expenses. Charities need to seek new sources of donations and work towards improvements in cost-effectiveness. Covenanting is on the increase due to the reduction in length of a deed of covenant from seven to four years. Administration and legal complexities must be exceeded by benefit values. Community funds are cost-effective methods of increasing donations. This increases interest level and awareness in a community as well as raising money. Cancer Research Campaign involved three unit trust schemes to individualize for different taxpayers' needs.

The Accounting Standard Committee (ASC) agreed on two statements which have already caused confusion among the preparers and users of accounts. The first pronouncement was an attempt to clarify how companies should account for deferred tax after changes announced in the budget. SSAP No.15 and ED 33 on deferred tax and SSAP No.6 on extraordinary items and prior year adjustments are now under review. The Statement of Intent on how companies should show the effects of inflation in their accounts marks a new stage in the inflation accounting debate.

An important element in any export drive is the financing and credit insurance. Finance is required for exporting because of research of new markets, manufacture and packaging of goods, the shipment period and period of credit granted to the buyer. The British Overseas Trade Board (BOTB) provides several schemes for market information and intelligence. It prepares detailed reports on particular markets and the chances of success of particular products. The banks provide finance for export by overdraft or loan, documentary credit, acceptance credit and Export Credits Guarantee Department (ECGD) bank guarantees. Factoring is a method of export finance by which an advance of eighty per cent of the value of invoice is given on evidence of shipment. The balance is payable after an agreed period. The ECGD is financing export by insurance coverage.

The introduction of an equity index futures contract and a recent change in the tax rules could bring the pension funds to the London International Financial Futures Exchange (LIFFE). Net profit from LIFFE contracts was taxed as income or gain on disposal of an investment. The tax treatment of transactions by exempt approved pension funds has fallen into line with that of other investments from December 13, 1983. Equity Index Futures Contract is a form of insurance against falling market for the person who owns or manages a portfolio. For the investor, it is a protection against rising share prices. There should be sufficient players who are willing to take on risks for the market to work. The major market makers will be the city institutions and exempt pension funds.

Interviews four members of Czechoslovakia's new government on their ideas and goals on economic and labor policy: Tomas Jezek, senior aide to Finance Minister Vaclav Klaus; Petr Miller, minister of labor and social affairs and his deputy minister Milan Horalec; Rita Klimova, ambassador to the United States; Future of trade unions; Role of foreign investors; Environment; Problem of employment.

Describes the disastrous ecological situation in Czechoslovakia. Repressive control of environmental information under former Communist Party; High rates of cancer, cardiac disease, and respiratory ailments; Effects of brown coal mining, power stations, and petrochemical plants; Environmental priority under President Vaclav Havel.

In the yeast Saccharomyces cerevisiae the transcriptionally active MAT alpha locus is repaired preferentially to the inactive HML alpha locus after UV irradiation. Here we analysed the repair of both loci after irradiating yeast cells at different stages of the mitotic cell cycle. In all stages repair of the active MAT alpha locus occurs at a rate of 30% removal of dimers per hour after a UV dose of 60 J/m2. The inactive HML alpha is repaired as efficiently as MAT alpha following irradiation in G2 whereas repair of HML alpha is less efficient in the other stages. Thus differential repair is observed in G1 and S but not in G2. Apparently, in G2 a chromatin structure exists in which repair does not discriminate between transcriptionally active and inactive DNA or, alternatively, an additional repair mechanism might exist which is only operational during G2.

Physiological studies have demonstrated a highly organized somatotopic representation of the body surface in SI cortex of rat. This representation is correlated morphologically with the presence of barrel-shaped structures in layer IV. Conventional staining techniques reveal barrels in the latter part of the first postnatal week. Recently, the peroxidase conjugates of lectins, which recognize glycosylated molecules, have been used to study barrel field formation. Con A, for example, has been shown to bind primarily to prospective barrel sides and septa as early as postnatal day 3 (PND-3) in mouse. To date, investigations of SI cortex using the lectin (Arachis hypogaea) peanut agglutinin (PNA) have been confined to the study of the barrel field representation of the face and mystacial vibrissae in the mouse. In the present study we extend these findings to the development of the representation of the entire body surface called the rattunculus. Rats ranging from PND-1 (first 24 h after birth) to PND-12 were anesthetized with Nembutal and perfused with 4% paraformaldehyde and 2% glutaraldehyde in 0.2 M sodium cacodylate buffer. Brains were removed, flattened tangentially, and sectioned on a vibratome at 30–120 microns. Sections were blocked in TRIS-buffered saline (TBS) plus 2% bovine serum albumin and incubated in peanut lectin at 4° C. Following incubation, sections were washed with TBS and processed using peroxidase histochemistry. Lectin binding in the prospective forelimb representation was apparent by PND-5 whereas lectin binding to the prospective face-mystacial vibrissae representation occurred before PND-4. These results suggest that body part representations show individual variations during early pattern formation. In rat, the representation of the limbs may lag behind the representation of the face-mystacial vibrissae during early postnatal development. This developmental gradient within the cortex may reflect a differential expression of lectin receptors.

A new approach to solid/liquid separation for biological precipitates is presented. The precipitate is seeded with small dense and/or magnetic particles to increase the density difference between precipitate and liquid or to make the precipitate amenable to magnetic separation. Experiments on seeding of ammonium sulphate precipitates of casein and separation of the seeded precipitate by gravity settling and batch centrifugation have shown that the approach holds promise. Seeded precipitates exhibit hindered settling under gravity with typical settling velocities of 0.6 cm/min for iron oxide seed and 2.4 cm/min for nickel seed. Calculations indicate that seeding of these precipitates causes a 23 fold increase in density difference between precipitate particle and supernatant liquid. The design of a magnetic seeding step for use in an enzyme isolation process is discussed.

Within the framework of a very long multifrequency campaign of coordinated, and very often simultaneous, observations of the transient X-ray/Be system A 0535+26/HDE 245770, we present a summary of this large collection of data taken with IUE and ASTRON satellites as well as with many ground-based telescopes in optical and IR regions.

Summary The physiological properties of neurons lying along the posterior bank of the ansate sulcus and the projection of these neurons to area 4γ of the motor cortex of the cat were studied and the following results were obtained: (1) Short latency antidromic responses were recorded from neurons along the medial-lateral bank of the posterior ansate sulcus following intracortical microstimulation (ICMS) delivered to motor cortex, area 4γ. (2) The posterior ansate region projects topographically to the motor cortex. Neurons in the most medial part of the ansate region project to the medial part of 4γ, while neurons in the central and lateral parts of the ansate region project to the more lateral parts of area 4γ. (3) In 33 cases, receptive field information was available for both the antidromically activated ansate neuron and from neurons around the stimulating site in 4γ. In 58% of the cases, both cortical sites received afferent input from within the same part of the periphery. (4) Afferent input to the motor cortex was examined following combined ablations of the primary somatosensory cortex (SI) and third somatosensory cortex (SIII) including all of area 5. We conclude that the integrity of these cortical regions is not necessary for afferent input to reach the motor cortex.

Abstract: Incorporation of indium into the quantum well materials of graded-index separate confinement heterostructure quantum well lasers has proven to be a key to imparting a much needed robustness to such lasers. By growing wells which contain both indium and aluminum along with gallium, operating wavelengths can be engineered to fall in the technologically important range of 0.8 microns, appropriate for pumping Nd:YAG. The organometallic vapor phase epitaxial growth of these strained-layer structures faces extra challenges rooted in the competing influences on the energies of the quantized states. At a minimum, meeting wavelength targets requires achieving control of the quaternary composition and of the quantum well thickness. Because laser elements are relatively large, lateral uniformity of wavelength is a critical issue. Device performance is influenced by basic material quality, which is a function of such fundamental growth parameters as temperature, V/III ratio, and growth rate. We have grown InAIGaAs structures using various combinations of growth conditions and well composition and thickness combinations, and evaluated and life-tested lasers in CW mode. The reactor’s performance in achieving composition and thickness uniformity is reported, as are data on the influence of the effects of growth conditions on device performance.

Ultraviolet irradiation of DNA induces cyclobutane pyrimidine dimers (CPDs), 6-4′-(pyrimidine 2′-one) pyrimidines and pyrimidine hydrates. The dimer is the major photoproduct, and is specifically recognized by endonuclease V of phage T4. Pyrimidine hydrates represent a small fraction of the total photoproducts, and are substrates for endonuclease III ofEscherichia coli. We used these enzymes to follow the fate of their substrates in the mating type loci ofSaccharomyces cerevisiae. In a RAD strain, CPDs in the transcriptionally activeMATα locus are preferentially repaired relative to the inactiveHMLα locus, whilst repair of endonuclease III-sensitive sites is not preferential. Therad1, 2, 3 and4 mutants, which lack factors that are essential for the incision step of nucleotide excision repair (NER), repair neither CPDs nor endonuclease III-sensitive sites, clearly showing that these lesions are repaired by the NER pathway. Previously it had been shown that the products of theRAD7 andRAD16 genes are required for the NER of CPDs from theHMLα locus. We show that, in the same locus, these gene products are not needed for removal of endonuclease III-sensitive sites by the same mechanism. This indicates that the components required for NER differ depending on either the type of lesion encountered or on the specific location of the lesion within the genome.

In the accompanying paper we demonstrated that endonuclease III-sensitive sites in theMATα andHMLα loci ofSaccharomyces cerevisiae are repaired by the Nucleotide Excision Repair (NER) pathway. In the current report we investigated the repair of endonuclease III sites, 6-4 photoproducts and cyclobutane pyrimidine dimers (CPDs) in arad14-2 point mutant and in arad14 deletion mutant. TheRAD14 gene is the yeast homologue of the human gene that complements the defect in cells from xeroderma pigmentosum (XP) patients belonging to complementation group A. In the point mutant we observed normal repair of endonuclease III sites (i.e. as wild type), but no removal of CPDs at theMATα andHMLα loci. Similar experiments were undertaken using the recently createdrad14 deletion mutant. Here, neither endonuclease III sites nor CPDs were repaired inMATa orHMRa. Thus the point mutant appears to produce a gene product that permits the repair of endonuclease III sites, but prevents the repair of CPDs. Previously it was found that, in the genome overall, repair of 6-4 photoproducts was less impaired than repair of CPDs in the point mutant. The deletion mutant repairs neither CPDs nor 6-4 photoproducts in the genome overall. This finding is consistent with the RAD14 protein being involved in lesion recognition in yeast. A logical interpretation is that therad14-2 point mutant produces a modified protein that enables the cell to repair endonuclease III sites and 6-4 photoproducts much more efficiently than CPDs. This modified protein may aid studies designed to elucidate the role of the RAD14 protein in lesion recognition.

It is well known that after the cessation of treatment by functional electrical stimulation (FES) there is a continuation of the improvement of the muscle function “carry-over”. If this could be harnessed and understood then this might lead to permanent improvement. An examination of evidence from FES, spasticity research and biofeedback might well produce the answers.Il est bien connu qu'apres l'arret d'un traitement de stimulation electrique fonctionnelle (FES) l'amelioration de la fonction musculaire du type “carry-over” se poursuit un certain temps. S'il etait possible de mieux saisir et comprendre ce phenomene on pourrait esperer pouvoir obtenir une amelioration durable. Une analyse approfondie des succes enregistres sous FES, associee a l'etude de la spasticite et aux applications du biofeedback pourraient bien en fournir la reponse.Es ist wohlbekannt, dass nach einem Unterbruch einer funktionellen Elektrostimulationsbehandlung (FES) die Verbesserung der Muskelfunktion noch eine Zeitlang anhalt. Bei besserem Verstandnis und guter Kontrolle liesse sich moglicherweise eine permanente Besserung erreichen. Von einer genauen Registrierung der FES-Wirkung, Forschung uber die Spastizitat und Biofeedback konnte man sich vielleicht eine Beantwortung der offenen Fragen erwarten.Es bien sabido que tras suspenderse el tratamiento a base de estimulo electrico funcional (EEF), se da una continuacion “de arrastre” de la mejoria de la funcion muscular. Si esto pudiera controlarse y comprenderse, se consiguiria una mejoria permanente. El examen de la evidencia del EEF, espasticidad, y la retrobioalimentacion bien pudiera darnos las respuestas.

From field and laboratory experiments it has been observed that low concentrations (ppb) of mineral hydrocarbons can cause an increase in photosynthesis among the nanoplankton. In field experiments, the increase in photosynthetic activity among the nanoplankton led to a bloom of µ-flagellates predominated by a member of the Haptophyceae,Chrysochromulina kappa.

(1) Intracortical microstimulation (ICMS) delivered to area 2 preinsularis (area 2 pr. i) of the second somatosensory cortex, SII, elicited contralateral distal limb movements with threshold currents as low as 2 µA. (2) The effective sites for a particular movement were located in a small area within the depth of the cortex extending along the direction of the radial fibers. (3) Neurons in an area for a particular movement generally received peripheral input from the skin overlying the muscle to which the area projected. (4) ICMS in area 2 pr.i produced powerful monosynaptic as well as disynaptic activation of pyramidal tract neurons, suggesting that the effect was mediated by the pyramidal tract. (5) Ablation of the motor cortex did not eliminate or otherwise reduce the low threshold responses from area 2 pr.i suggesting that the described effect is independent of the motor cortex.

Summary: Neurons in the parietal region of the cerebral cortex, projecting to the ipsilateral distal forelimb area of the motor cortex (area 4gamma) were identified in the cat brain using the horseradish peroxidase (HRP) retrograde tracing method. After making microinjections of HRP into the distal forelimb area of the motor cortex, clusters of HRP-labeled cell bodies were observed in different regions of the ipsilateral parietal cortex. In particular these clusters of labeled cells were found in areas 5a, 5b and 7. The area 5a cluster is formed from closely packed irregularly-shaped cells, the area 5b cluster is made up of dispersed medium-sized pyramidal cells, while area 7 contains a cluster of widely dispersed small pyramidal cells. Typically, labeled cell bodies were found in lamina III of cortex. Labeled cell bodies were neither observed in the contralateral cortex nor in the visual cortex (areas 17, 18 and 19). Since parietal cortex receives projections from primary somatosensory and visual cortex, the projections from parietal to motor cortex may well form the neural substrate for the processing of convergent sensory information used in voluntary movements.