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The role of the environment on the formation of S0 galaxies is still not well understood, specifically in the outskirts of galaxy clusters. We study eight low-redshift clusters, analyzing galaxy members up to cluster-centric distances $\sim2.5\,R_{200}$. We perform 2D photometric bulge-disk decomposition in the $g$-, $r$- and $i$-bands from which we identify 469 double-component galaxies. We analyze separately the colors of the bulges and the disks and their dependence on the projected cluster-centric distance and on the local galaxy density. For our sample of cluster S0 galaxies, we find that bulges are redder than their surrounding disks, show a significant color-magnitude trend, and have colors that do not correlate with environment metrics. On the other hand, the disks associated with our cluster S0s become significantly bluer with increasing cluster-centric radius, but show no evidence for a color-magnitude relation. The disk color-radius relation is mainly driven by galaxies in the cluster core at $0\leq R/ R_{200}, 30 pages (including 3 pages of appendices), 18 Figures, 10 Tables. Accepted for publication in ApJ. Please see "Other formats" or "Ancillary files" to download the data from the $g$-, $r$- and $i$-bands bulge-disk decompositions

We explore stellar population properties separately in the bulge and the disk of double-component cluster galaxies to shed light on the formation of lenticular galaxies in dense environments. We study eight low-redshift clusters from the Sydney-AAO Multi-object Integral field (SAMI) Galaxy Survey, using 2D photometric bulge-disk decomposition in the $g$, $r$ and $i$-bands to characterize galaxies. For 192 double-component galaxies with $M_{*}>10^{10~}M_{\odot}$ we estimate the color, age and metallicity of the bulge and the disk. The analysis of the $g-i$ colors reveals that bulges are redder than their surrounding disks with a median offset of 0.12$\pm$0.02 mag, consistent with previous results. To measure mass-weighted age and metallicity we investigate three methods: (i) one based on galaxy stellar mass weights for the two components, (ii) one based on flux weights and (iii) one based on radial separation. The three methods agree in finding 62% of galaxies having bulges that are 2-3 times more metal-rich than the disks. Of the remaining galaxies, 7% have bulges that are more metal-poor than the disks, while for 31% the bulge and disk metallicities are not significantly different. We observe 23% of galaxies being characterized by bulges older and 34% by bulges younger with respect to the disks. The remaining 43% of galaxies have bulges and disks with statistically indistinguishable ages. Redder bulges tend to be more metal-rich than the disks, suggesting that the redder color in bulges is due to their enhanced metallicity relative to the disks instead of differences in stellar population age., 38 pages (including 5 pages of appendices), 23 Figures, 5 Tables. Accepted for publication in ApJ

We explore how the group environment may affect the evolution of star-forming galaxies. We select 1197 Galaxy And Mass Assembly (GAMA) groups at $0.05\leq z \leq 0.2$ and analyze the projected phase space (PPS) diagram, i.e. the galaxy velocity as a function of projected group-centric radius, as a local environmental metric in the low-mass halo regime $10^{12}\leq (M_{200}/M_{\odot})< 10^{14}$. We study the properties of star-forming group galaxies, exploring the correlation of star formation rate (SFR) with radial distance and stellar mass. We find that the fraction of star-forming group members is higher in the PPS regions dominated by recently accreted galaxies, whereas passive galaxies dominate the virialized regions. We observe a small decline in specific SFR of star-forming galaxies towards the group center by a factor $\sim 1.2$ with respect to field galaxies. Similar to cluster studies, we conclude for low-mass halos that star-forming group galaxies represent an infalling population from the field to the halo and show suppressed star formation., 23 pages, 31 figures

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of morbidity and mortality worldwide. The symptoms of COPD are troublesome, variable, can occur during all parts of the 24-h day and have a substantial impact on patients' health status, quality of life and healthcare resource utilization. Reducing symptoms, improving health status and increasing physical activity are major goals in the management of stable COPD. In order to provide effective, patient-oriented care, patients should be evaluated on the basis of lung function, frequency of symptoms and patient-perceived impact of symptoms on their lives and treatment decisions made on a case-by-case basis. The identification of COPD phenotypes is an evolving debate and literature data about the circadian variation of COPD symptoms according to phenotypes are nowadays lacking. The ongoing STORICO ( STudio Osservazionale sulla caratteRizzazione dei sIntomi delle 24 ore nei pazienti con BPCO ) study ( NCT03105999 ) is aimed to describe by clinically defined phenotypes the frequency and 12-month evolution of early-morning, day- and night-time COPD symptoms in a cohort of 600 Italian patients with stable COPD. Secondary objectives include the description of the 12-month variation of outcomes of interest according to phenotypes and of the healthcare resources utilization (overall and by phenotype) during 12-month observation. An exploratory analysis will be conducted aimed to phenotype COPD patients in an alternative researcher-independent way based on circadian pattern of symptoms combined with measures of respiratory function, health-related quality of life and comorbidity. The present paper describes the methodology of the STORICO study.

Our study is meant to extend our knowledge of the galaxy color and luminosity segregation in velocity space (VCS and VLS, resp.), to clusters at intermediate and high redshift. Our sample is a collection of 41 clusters in the 0.4=0.8. For the first time, we detect VLS in non-local clusters and confirm that VLS only affects the very luminous galaxies, with brighter galaxies having lower velocities. The threshold magnitude of VLS is ~m3+0.5, where m3 is the magnitude of the third brightest cluster galaxy, and current data suggest that the threshold value moves to fainter magnitudes at higher redshift. We also detect (marginal) evidence of VLS for blue galaxies. We conclude that the segregation effects, when their study is extended to distant clusters, can be important tracers of the galaxy evolution and cluster assembly and discuss the poor/no evidence of VCS at high redshift., Comment: A&A accepted, 12 pages, 10 figures

The expansion in vacuum of the plume generated by the UV ablation of a LiYF4 crystal was analysed as a function of several parameters: distance from the target along the plume axis, laser fluency and angular dislocation with respect to the plume axis. The study was carried out by the optical time of flight technique. Time-resolved signals of the optical emission of the neutral as well as ionised species in the plume were recorded and analysed for different experimental situations. The most probable velocity for each species was calculated and confirmed by the Maxwell-Boltzmann distribution fits of the relative emission temporal profiles. An angular distribution of the ablated species could also be provided.

The realization of crystalline sub micrometric films of Nd 3+ :LiYF 4 fluorides on pure LiYF 4 substrates by pulsed laser deposition is reported. The films were obtained by laser ablation with 355 nm photons of a bulk LiYF 4 crystal doped with Nd 3+ ions at 1.5% atomic concentration. Both low and high laser ablation fluency regimes were checked. The fundamental contribution of He inside a vacuum chamber to obtain crystalline Nd 3+ :LiYF 4 films was demonstrated. The optical characteristics of the films were analyzed via recording the emission spectra following IR excitation, polarized both with E II and E ⊥ to the substrate c-axis. Lifetime measurements of the fundamental Nd 3+ ion transition in the films were also performed. All the results were compared with those obtained in the Nd 3+ :LiYF 4 bulk crystal under the same experimental conditions. The scanning electron microscope pictures of the depositions gave indications about the film surface morphology.

The realization of crystalline films of Nd3+:YF3 and Nd3+:LiYF4 on a monocrystalline LiYF4 substrate by pulsed laser deposition is reported. The films were obtained by laser ablation with 355 nm photons of a bulk LiYF4 crystal doped with Nd3+ ions at 1.5% atomic concentration in the presence of different ablation/deposition parameters. The films optical characteristics, analyzed via laser induced polarized fluorescence spectroscopy upon IR excitation, are presented. Lifetime measurements of the fundamental Nd3+ ion transition in the film were also performed. All these results were compared with those obtained in the Nd3+:LiYF4 bulk crystal. The surface morphology of the depositions was analyzed via a scanning electron microscope. When the production of the deposition took place in high vacuum (1 × 10− 4 Pa) and the substrate temperature was 750 °C, the grown film was Nd3+:YF3. A 1 Pa controlled atmosphere of He in the ablation chamber and a substrate temperature of 650 °C favoured the growth of a Nd3+:LiYF4 film. In the latter case the film showed also a smoother surface.

The spectroscopy of dense Ga, In and In–Ga vapours is studied via resonant pulsed laser excitation at 403.4 nm (Ga) and 410.3 nm (In). Besides some known atomic Rydberg levels emission, satellite wings on the blue side of the fundamental transitions show up both in the homonuclear and heteronuclear vapours. They are due to the presence of excited homonuclear dimers that form in the collision between excited and ground-state atoms. The formation of heteronuclear dimers is inferred by the time-resolved analysis of some atomic fluorescences.

We present the first spectroscopical analysis of the Ga/SiO2 surface interaction in hot environment. This interaction gives rise to inclusions of Ga atoms inside the silica matrix that produce structural changes and modify the SiO2 optical characteristics. This paper discusses both the time- and the frequency-resolved spectra of the fluorescence emission following UV pulsed laser excitation of the so “doped” silica in the range 15,000–28,000 cm−1. The investigation is completed by the electron paramagnetic resonance (EPR) spectra of two high-purity synthetic silica samples of commercial origin after thermal treatment in presence and in absence of a Ga atmosphere.

We performed temporal as well as frequency-resolved emission spectroscopy of the plasma plume generated in vacuum by 355 nm pulsed laser ablation of a LiYF 4 :Tm 3+ crystal (1% Tm 3+ concentration) and a LiYF 4 :Nd 3+ crystal (1.5% Nd 3+ concentration). The plume emission spectrum is very rich in features and shows the elemental lines belonging to all the components of the host lattice, either neutral or ionized. The time-resolved analysis of some emission features is discussed and some stream velocities are derived. A possible model for the time evolution of the plume components is reported. The electronic detection technique was used to detect the onset of the plasma plume and to measure the ablation laser fluence threshold.

The production of Rydberg atoms via collisions in a resonantly laser excited dense In vapour is reported. When a dense In vapour confined in a quartz cell, whose temperature is raised above 820 °C, is excited by 100 kW cm−2 laser pulses at 410.3 nm, resonant with the fundamental transition 5 2P1/2 → 6 2S1/2, the fluorescence spectrum shows radiative emissions from Rydberg states, namely those corresponding to the n 2P → 6 2S1/2 series with 9 ≤ n ≤ 23. Fluorescences corresponding to the 5 2D → 5 2P1/2,3/2 transitions are also observed. Analysis of these signals' intensity as a function of several different experimental parameters, such as the atomic density and the laser power density, indicates that the population in the Rydberg levels is produced mainly by energy pooling collisions (EPC). The EPC cross section for the population of the Rydberg levels is also given. The influence on these effects of the presence of a fine structure in the In ground state (5 2P1/2,3/2) is also discussed, as well as the presence of a buffer gas inside the quartz cell.

This paper reports on the excitation of the nP→52S1/2 series, when Ga vapour inside a quartz cell, with or without buffer gas, at a temperature larger than 900°C, is resonantly excited by laser pulses at 403.3 nm corresponding to the 42P1/2→52S1/2 excitation. The analyses of the fluorescence intensities as a function of several different experimental parameters demonstrate the nP levels to be populated via energy-pooling ionisation.

We present the first results about the quenching of the radiation trapping in Ga vapour kept in a quartz cell when its temperature exceeds 1000°C, corresponding to an atomic density≅10 13 cm −3 . We show that this unusual behaviour is due, besides the energy-pooling ionisation effect, to the formation of fluorescent centres inside the quartz lattice in the interaction between Ga atoms and the fused silica structure. The first preliminary quantitative results are also reported.

In this paper we report on the atomic population redistribution originating from the ionization that takes place in a dense Ga vapour kept in quartz cells and resonantly excited by laser radiation, in the collisions between two excited atoms. This ionization process is known as energy-pooling ionization (EPI). The electron/ion recombination that takes place in the low density plasma produced gives rise to population in the atomic Rydberg levels and from the latter via cascade transitions to lower lying ones. We have monitored the fluorescences relative to the radiative emissions from such levels, namely those corresponding to the nP → 5S1/2 series, with 9 ≤ n ≤ 26, and the 4D → 4P1/2,3/2 transitions. Their characteristics testify to their origin as being due to the EPI process. Further confirmation is obtained by performing a time-resolved analysis of such fluorescences, whose appearance and time evolution is strongly influenced by the dynamics of the process. The effect of the introduction of a few Torr of buffer gas inside the quartz cell, resulting in the quenching of all the fluorescences for n ≥ 12, is also discussed.

We report on the electronic detection of the energy-pooling ionization (EPI) process in resonantly laser-excited gallium vapour. The formation of electrons and ions in the collision of two Ga atoms excited to the 5 2S1/2 level is analysed as a function of several different parameters such as the laser power density, the atomic density and the temperature. The influence of the strong chemical reactivity of Ga at high temperatures on the process is also evidenced. Finally the cross section for the EPI process is derived from the electronic signals detected. It turns out to be (1.1±0.5)×10-15 cm2, a large value that states EPI as a very efficient process in Ga vapour.

Resume Le rachitisme hypophosphatemique familial (RHF) s'accompagne volontiers d'un retard de croissance et d'une petite taille a l'âge adulte, meme si le traitement conventionnel par phosphate et calcitriol ou 1α-hydroxyvitamine D est bien conduit. La pathogenie de ce deficit statural n'est pas eclaircie ; la secretion d'hormone de croissance (GH) est habituellement normale. Un traitement de GH recombinante (GHr) a ete entrepris pendant une duree de 6 ans chez six enfants porteurs d'un RHF (âge: 7,8 ±1,8 ans) porteurs d'un RHF avec retard de croissance important (score Z moyen: − 3,4 ± 0,5) recevant par ailleurs un traitement conventionnel. Un groupe temoin etait compose de six enfants porteurs d'un RHF (âge: 7,9 ± 2,5 ans) ne recevant que le traitement conventionnel. Le traitement de GHr a entraine une amelioration de la croissance staturale avec augmentation significative du score Z et de la prediction de taille adulte, le gain statural etant significativement plus eleve dans le groupe traite comparativement au groupe temoin. Parallelement, etait observee une augmentation de la densite minerale osseuse radiale. Le traitement par GHr apparait donc comme un complement utile au traitement conventionnel, permettant d'ameliorer la qualite de la croissance des enfants avec RHF.

The realization of a monocrystalline nanofilm of Nd3+-doped fluoride on LiYF4 substrates by pulsed laser deposition is reported. The film was obtained by laser ablation with 355 run photons of a bulk LiYF4 crystal doped with Nd3+ ions at 1.5% atomic concentration. The measurements of the sample thickness obtained by an in situ interferometric technique, and the film optical characteristics analyzed via laser induced fluorescence spectroscopy upon UV and IR excitation, are presented. Lifetime measurements of the fundamental Nd3+ ion transition in the film were also performed. All the results were compared with those obtained in a Nd3+:LiYF4 bulk crystal. The emission spectra of the deposited film following IR excitation seem to indicate the obtained deposit is Nd3+:YF3. (c) 2007 Elsevier B.V All rights reserved.

Monocrystalline Nd-doped LiYF4 (YLF) nanofilms are deposited on YLF substrates by pulsed laser deposition. Interferometric technique, laser-induced fluorescence spectroscopy and infrared spectroscopy are employed to determine the film thickness, photoluminescence and absorption band of the obtained samples.

We show how the interaction between Ga atoms and silica samples in a hot environment gives rise to permanent inclusions of Ga inside the silica matrix which, in turn, produce typical luminescence features. The Ga doped silica is analyzed via laser induced fluorescence, photoluminescence and electron paramagnetic resonance spectroscopies. The results evidence the presence of modifications induced by the Ga inclusions inside the silica matrix and some preliminary hypothesis on their nature are advanced. Possible applications of such Ga doped silica are also mentioned.

To assess whether delaying puberty may improve final height in GH-deficient children with a poor height prediction at early puberty, we studied 24 girls with isolated GH deficiency until they reached their final height, in a controlled trial. Patients were taking recombinant human GH (r-hGH) substitutive therapy from 2.1 +/- 0.5 yr (0.1 IU/kg.day sc) before entering the study, without showing any improvement in height prediction (149.6 +/- 2.9 vs.150.3 +/- 2.2 cm) on entering puberty. Fourteen girls agreed to add a GnRH agonist (GnRHa) to r-hGH, whereas the remaining 10 decided against it and served as controls. At the start of the study, girls treated with or without GnRHa had similar auxological characteristics (bone age, 10.9 +/- 0.6 vs. 10.7 +/- 1.3 yr; height SD score for chronological age, -1.87 +/- 0.3 vs. -1.82 +/- 0.2), including pubertal development. The GnRHa (long-acting D-Trp-6-GnRH) was given at 60 microg/kg im every 28 days for 1.9 +/- 0.9 yr, then patients continued the r-hGH at the same dosage (3.1 +/- 0.7 yr). At the end of the study, bone age was 16.2 +/- 0.3 yr in GnRHa-treated girls and 16.6 +/- 0.9 yr in controls. Bone maturation was significantly slower during GnRHa (1.4 +/- 0.2 yr), and height SD score for bone age improved (-0.31 +/- 0.3) in comparison with controls (2.6 +/- 0.4 yr and -1.35 +/- 0.3 SD score; P < 0.001 and P < 0.0001, respectively). As a result, girls given the combined therapy reached a final height higher than that of controls (height SD score, -0.39 +/- 0.5 vs. -1.45 +/- 0.2; P < 0.0001) and also higher than their midparental height (-1.1 +/- 0.5; P < 0.0005). Controls reached their midparental height. In conclusion, our results demonstrate that slowing pubertal development with the administration of GnRHa for a limited time may improve final height in GH-deficient girls selected because of a poor height prediction at early puberty.

The pubertal growth spurt accounts for approximately one-eighth of adult height and is regulated by complex hormonal interactions involving the somatotropic and gonadal axes. The observation that children with growth hormone deficiency (GHD) may fail to achieve an appropriate pubertal growth spurt led to the development of strategies to optimize GH therapy during puberty. In one strategy the dosage of GH is increased during puberty to support pubertal growth and in keeping with the physiological increase in serum levels of the hormone seen at that age. A different approach is to combine a GnRH analog (GnRHa) to GH to stop pubertal development, delaying epiphyseal fusion and prolonging peripubertal growth. Both strategies require caution. As regards the first strategy, too high doses of GH may shorten the pubertal time for growth; we found a small, nonsignificant, improvement in final height by increasing the dose by less than half. Preliminary results on the second strategy are more encouraging. However, manipulation of puberty should be limited to selected patients who show a statural height SDS for bone age unfavorable in terms of height prognosis.

The availability of recombinant human growth hormone (GH) and the optimization of substitutive therapy have improved final growth in children with GH deficiency, but despite this some of them fail to grow to their genetic potential. In particular, this may occur in patients who started the substitutive therapy too late and/or in whom bone age progressed too fast during GH administration. In these patients, with unfavorable auxological characteristics, the administration of a GnRH agonist in combination with GH may slow down bone maturation and prolong prepubertal growth, mimicking, to some extent, the growth pattern of patients with GH + Gn deficiency who grow better than children with isolated GHD. A different condition in which such a combined therapy might be used is the short normal child. As they are short but normally-growing children, the onset of puberty is in general appropriate for their chronological age but precocious for their height age. Thus, slowing down pubertal maturation may increase the time available for growth. GH would sustain growth during both GnRHa administration and after its withdrawal, when puberty starts again. Our preliminary results suggest that the administration of GH + GnRHa in combination may have a positive effect on final height in selected children with isolated GHD and in short normal children.

X-linked hypophosphatemic rickets (XLHR) is frequently associated with growth retardation and short adult stature, even with an appropriate conventional treatment associating phosphate and calcitriol or 1 alpha-hydroxyvitamin D. Its pathogenesis is unclear; growth hormone (GH) secretion is usually normal. Six children with XLHR and growth retardation were treated with GH during 6 years. In addition, they received the conventional treatment. At the beginning of the treatment mean age was 7.8 +/- 1.8 years, and height mean Z score was -3.4 +/- 0.5. A control group was composed of six children with XLHR (age: 7.9 +/- 2.5 years) receiving the conventional treatment only. Under GH treatment statural growth was improved, with significant increase in Z score and predicted adult height; the height gain was significantly higher in the GH treated group as compared with the group receiving the conventional treatment only. In addition, radial bone mineral density increased significantly under GH treatment. GH treatment thus appears to be a useful treatment to improve statural growth in children with XLHR.

The effect of long-term GH treatment on bone mass was examined in 32 children with GH deficiency (GHD) aged 7.2-16.3 yr by measuring radial (distal third, single-photon absorptiometry) and lumbar (L2-L4, dual energy x-ray absorptiometry) bone mineral density (BMD) (group A). All patients were longitudinally followed and received recombinant hGH therapy for a mean period of 48.2 +/- 13.2 months. BMD values were corrected for bone age and expressed as Z-score in comparison with normative data. In addition, lumbar BMD and lumbar BMD corrected for the estimated vertebral volumes were assessed in 11 patients with GHD aged 16.0 - 18.7 yr at the time they reached their final height (group B) and, in 17 subjects with familial short stature aged 16.4 - 19.8 yr, as controls (group C) for patients of group B. Patients of group B had received discontinuous treatment with pituitary-derived hGH and subsequently recombinant hGH (total duration of treatment 151.5 +/- 9.7 months). The off-treatment period was 4.7 +/- 2.6 months. Before treatment, patients of group A showed significantly reduced (P0.001) radial and lumbar BMD (-1.7 +/- 0.4 Z-score and -1.5 +/- 0.5 Z-score, respectively) compared with normative data. During treatment, radial and lumbar BMD Z-scores improved significantly (P0.001); in the patients treated for the longest time, the BMD was within 0.5 SD of age-matched mean levels. In patients of group B, lumbar BMD and lumbar BMD corrected for the estimated vertebral volumes were significantly reduced in comparison with subjects of group C (-1.2 +/- 0.4 Z-score and -1.0 +/- 0.4 Z-score, P0.01 and P0.03, respectively). The results show that children with GHD have reduced BMD. Optimal GH treatment improves BMD, whereas inappropriate treatment is a main cause of reduced BMD at time of final height. These findings suggest an important role of GH therapy in the attainment of peak bone mass in children with GHD. GH treatment should be continued until the attainment of peak bone mass irrespective of the height achieved.

To improve final adult height, we treated with growth hormone (0.65 +/- 0.07 (mean +/- SD) IU.kg-1.wk-1) and gonadotropin-releasing hormone analogs (66 +/- 9 micrograms.kg-1 every 28 days) a group of seven short normal girls in early puberty with a chronologic age (CA) of 11.50 +/- 0.95 years, predicted adult height (PAH) lower (0.003 < p < 0.001) than mean target height, and without any endocrine abnormalities. The results were compared with those obtained in a similar group of seven untreated girls considered as control subjects. The mean period of combined therapy was 2.01 +/- 0.52 years; in two subjects treatment is still in progress. The value of height standard deviation score for bone age (BA) improved from -1.69 +/- 0.47 to -1.04 +/- 0.56 (p = 0.001); height age (HA)/BA ratio also increased from 0.83 +/- 0.05 to 0.90 +/- 0.04 (p < 0.01), as did PAH (from 146.8 +/- 4.4 to 152.9 +/- 3.6 cm; p < 0.002). The ratio of gain in HA to gain in BA was 2.08 +/- 0.78. Pubertal stages showed an arrest in five cases and a regression in the other two girls. After administration of gonadotropin-releasing hormone analogs was interrupted, in four of five girls growth hormone was administered alone for a further period of 6 to 18 months to improve their physiologic growth spurt. The present height in five girls is higher than PAH before therapy. In the treated girls the height values for BA, for BA/CA and HA/BA ratios, and for PAH were higher (0.002 < p < 0.04) than those in control subjects. This preliminary study demonstrates that combination therapy with growth hormone and gonadotropin-releasing hormone analogs in short, endocrinologically normal girls may be useful in improving both height prognosis and predicted adult height. Further studies are necessary to reach definitive conclusions regarding the efficacy of this kind of therapy.

The first report of occupational acquisition of HIV appeared in 1984, and, by June, 1997, the Centers for Disease Control and Prevention (CDC) had reported 52 documented cases of sero-conversion following occupational exposure to HIV-1 by health care workers of those cases. 47 (90.3%) were exposed to blood. The most frequent type of accident reported was percutaneous needlestick injury. Prospective studies have estimated that the risk of HIV transmission following percutaneous exposure to infected blood is 0.3% (Confidence Interval 95% = 0.2% to 0.5%). Following a mucous membrane exposure, the risk is 0.09% (CI 95% = 0.006% to 0.5%). The risk of hepatitis B acquisition ranges from 6% to 30%, and hepatitis C acquisition, 3% to 10%. Since 1992, the São Paulo Hospital's Hospital Infection Prevention and Control Service (SPCIH) has notified and treated all workers exposed to accidents involving biological materials. In the last six years, we have handled approximately 1,300 cases of reported accidents, of which 90% were percutaneous, most involving needlesticks. Such cases were frequently caused by the inadequate disposal and recapping of needles. In these accidents, 20% of the source patients were HIV positive, 10% were hepatitis C positive, and 7.6% were hepatitis B positive. This review summarizes the guidelines for a standardized response when dealing with accidents involving health care workers. Transmission of hepatitis B and HIV can be reduced if adequate preventive measures are taken in advance. If proper prophylaxis is not being done, it should be initiated immediately.