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The Sasso Fratino Integral Natural Reserve (Central Italy), a rare example of climax Mediterranean forest, provides an extraordinary opportunity to create an important soundscape reference of old-growth forest. In this study, we describe the soundscape of three localities (Lama, Sasso 950, Sasso 1400) representative of a gradient of variety and complexity of habitats, recorded during the period 10 May to 9 June 2017. Our results reveal temporal partitioning into acoustically homogeneous periods across 24 h suggesting that soniferous species (mainly birds) adopt ecological routines in which their acoustic activity is organized according to specific transient physiological needs. We processed multi-temporal aggregates of 1, 5, 10, and 15 s recordings and calculated the Acoustic Signature (AS) with four new indices: Ecoacoustic Events (EE), Acoustic Signature Dissimilarity (ASD), and their fractal dimensions (DEE and DASD), derived from the Acoustic Complexity Index (ACI). The use of the EE and ASD greatly improved the AS interpretation, adding further details such as the emergence of a clear sequence of patterns consistent with the daily evolution of the overall soundscape. DEE and DASD confirm the patterns observed using the AS, but provide more clarity and detail about the great acoustic complexity that exists across temporal scales in this old-growth forest. The temporal turnover of different acoustic communities occurs as a result of a gradual shift of different homogenous acoustic properties. We conclude that soniferous species use distinct, species-specific temporal resolutions according to their physiological and ecological needs and that the fractal approach used here provides a novel tool to overcome the difficulties associated with describing multi-temporal acoustic patterns.

Background: Matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) proteomic signature might be of interest for the early detection and staging of hepatocellular carcinoma (HCC). However, published procedures have been criticized for the lack of data about analytical reproducibility, and the use of inadequate data processing. Methods: MALDI-TOF profiling of peptides bound to serum albumin (“albuminome”) was performed using 90 μL of serum from 45 study subjects (HCV-related cirrhosis, small, unifocal HCCs and advanced HCCs). To overcome the large intra-sample variability, a Quality Assurance protocol was implemented, and 4–8 samples for each subject were processed and analyzed. Overall, 522 subject samples and 299 quality-control spectra were analyzed. A machine-learning approach (Random Forest) was applied to analyze the data sets. Results: Mean intra-sample coefficient of variation (CV) of the analytical procedure was 17.6%–30.0%; inter-subject CV was in the range 48.8%–71.3% among the three study groups. The Random Forest procedure correctly classified 433/522 “patient samples” and 295/299 “reference samples”; 43/45 patients were correctly classified following this approach. Conclusions: Our data suggest that, notwithstanding the large analytical variability found, multiple proteomic profiles obtained from each subject can differentiate cirrhosis with and without HCC, and HCCs with and without vascular invasion, warranting further investigation in a prospective setting. Clin Chem Lab Med 2010;48:1319–26.

PURPOSE: Hepatic hydrothorax is defined as the accumulation of pleural effusion in a cirrhotic patient in the absence of pulmonary or cardiac disease. Peritoneal fluid can pass into the pleural space through diaphragmatic fenestrations. The demonstration of such passage is important to establish the diagnosis of hepatic hydrothorax and can be achieved by intraperitoneal injection of nuclear contrast agents. Our aim was to evaluate the ability of contrast enhanced ultrasound in the detection of peritoneal-pleural communications. MATERIALS AND METHODS: Seven patients with cirrhotic ascites and pleural effusion were studied in order to make a diagnosis of hepatic hydrothorax. SonoVue was injected into the peritoneal cavity (9.8 mL), and the peritoneal and pleural cavities were monitored by ultrasound. All patients were then studied using a nuclear scan. RESULTS: Passage of SonoVue from the peritoneal to the pleural cavities was seen in 5 patients. In 2 patients, no passage of contrast agent was detectable. Nuclear scan was consistent with contrast enhanced ultrasound in all patients. CONCLUSION: This study shows that the presence of peritoneal-pleural communications can be demonstrated by real time contrast enhanced ultrasound, whose results are comparable to those of nuclear scan. Contrast enhanced ultrasound is cheaper and could theoretically be performed wherever ultrasound facilities are available.

Summary Aim To evaluate the acute effect of treatment with the molecular adsorbent recirculating system (MARS) on splanchnic, renal and systemic haemodynamics in patients with end-stage cirrhosis. Methods Twelve patients with end-stage cirrhosis, undergoing MARS treatment, were enrolled. The following haemodynamic parameters were measured by means of Doppler ultrasonography and thoracic electrical bioimpedance, before and after each session: portal velocity, renal and splenic resistance indices, cardiac output, cardiac stroke volume, heart rate, mean arterial pressure, systemic vascular resistance. Results Median portal velocity increased significantly after treatment (23.7 vs. 20.3 cm/s, P

ENEA (an Italian Research Institute) is developing in collaboration with some European companies (ATC - Italy, ANSALDO - Italy, SIVECO Group - France and IIS sa - Greece) and within an international Project financed by the European Commission (Contract No BRPR - CT96-0211 relative to the Project Proposal No. ERB1531 PL - BE 95 1007) a software tool which will be marketed for its application in the improvement of the maintenance planning of each type of complex system (industrial production lines, each type of networks, power production plants, transport systems, etc.) on the basis of reliability and cost criteria The description of this software tool, the development of which is in a completion phase, is the subject of the present paper. First of all, the main goals to be reached by its application to the industry (mainly high savings in the maintenance management costs and availability growth) will be mentioned. Besides, after a short description of the main features of the existing CMMS (Computer Maintenance Management Systems), details will be given on the software tool, on its constituting computer methods and devices and on its application mode. The innovative characteristics of each constituting method will be demonstrated

Focal nodular hyperplasia (FNH) is the second most common benign tumor of the liver, after hemangioma. It is generally found incidentally and is most common in reproductive-aged women, but it also affects males and can be diagnosed at any age. Patients are rarely symptomatic, but FNH sometimes causes epigastric or right upper quadrant pain. The main clinical task is to differentiate it from other hypervascular hepatic lesions such as hepatic adenoma, hepatocellular carcinoma, or hypervascular metastases, but invasive diagnostic procedures can generally be avoided with the appropriate use of imaging techniques. Magnetic resonance (MR) imaging is more sensitive and specific than conventional ultrasonography (US) or computed tomography (CT), but Doppler US and contrast-enhanced US (CEUS) can greatly improve the accuracy in the diagnosis of FNH. Once a correct diagnosis has been made, in most cases there is no indication for surgery, and treatment includes conservative clinical follow-up in asymptomatic patients.SommarioL'iperplasia nodosa focale (FNH) è il tumore epatico benigno più frequente dopo l'angioma. E' di solito rilevata in modo occasionale, per lo più nelle donne in età fertile, anche se si può riscontrare in entrambi i sessi e ad ogni età. I soggetti portatori raramente sono sintomatici, nonostante l'FNH possa essere causa di dolore ai quadranti addominali superiori. Nella gestione dell'FNH il problema clinico principale è rappresentato dalla difficoltà di differenziarla dalle altre lesioni epatiche ipervascolarizzate, come l'adenoma, l'epatocarcinoma o le metastasi ipervascolari, tuttavia utilizzando le opportune tecniche diagnostiche è oggi possibile evitare il ricorso ad esami invasivi. La Risonanza Magnetica (RM) ha una sensibilità e una specificità superiori rispetto a quelle dell'ecografia convenzionale e della Tomografia Assiale Computerizzata (TC) per la diagnosi di FNH. L'uso dell'angioecografia perfusionale (CEUS) e dell'eco-Doppler può tuttavia aumentare in modo significativo la confidenza diagnostica nell'identificazione e nella caratterizzazione dell'FNH con ultrasuoni. Una volta posta con certezza la diagnosi, nella maggior parte dei casi non ci sono indicazioni al trattamento chirurgico e nei soggetti asintomatici è raccomandato un follow-up clinico.

Safety issues should always be kept in mind when using diagnostic ultrasound, which is associated with potentially hazardous bio-effects, especially with the introduction of new technologies.To assess the level of awareness and knowledge of safety issues related to the clinical use of ultrasound among physician-members of the Italian National Society for Ultrasound.A questionnaire with 11 multiple-choice questions was sent to members of the Italian Society for Ultrasound in Medicine and Biology. The answers were forwarded from the Society's Secretariat to the investigators, who statistically analyzed the data.The mean age of the 105 respondents was 44 years. The most frequent kind of ultrasound examinations (in addition to conventional B-mode) were: Doppler (74%), contrast-enhanced US (43%), and pediatric studies (43%). Only 50-60% of the responders knew the correct definitions of the terms thermal index and mechanical index. Almost all respondents understood the bio-effects reflected by the thermal index, but only a minority knew the most likely organ target of bio-effects related to the mechanical index and what do indicate the units in which the thermal index is expressed. The majority knew that fetuses are at higher risk of damage. Few respondents were able to identify the correct safety statements included in the recommendations of the International Ultrasound Societies.In conclusion, the present findings indicate that greater efforts of National Ultrasound Societies are warranted in disseminating knowledge of the bio-effects of diagnostic ultrasound modalities among operators.Sommario INTRODUZIONE: La sicurezza nell'uso degli ultrasuoni va sempre considerata in campo ecografico, in quanto gli ultrasuoni sono in grado di indurre effetti biologici potenzialmente dannosi, soprattutto con l'introduzione di nuove tecnologie. SCOPO DELLO STUDIO: Valutare il livello di consapevolezza e di conoscenza dei medici italiani soci SIUMB sulla sicurezza nell'uso dell'ecografia nella pratica clinica. MATERIALI E METODI: Un questionario contenente 11 domande a risposta multipla è stato inviato per e-mail a soci SIUMB (Società Italiana di Ultrasonologia in Medicina e Biologia). Le risposte sono state inserite in un database elettronico ed analizzate statisticamente. RISULTATI: Sono tornati questionari da 105 soci, di età media di 44 anni i cui esami ecografici più frequentemente eseguiti, in aggiunta all'ecografia B-mode standard, erano l'ecoDoppler (74%), l'ecografia con mezzo di contrasto (43%) e l'ecografia pediatrica (43%). Solo il 50–60% conosceva la definizione corretta dell'Indice Meccanico e dell'Indice Termico. Quasi tutti i partecipanti comprendevano gli effetti biologici espressi con Indice Termico, nonostante che solo una minoranza sapesse in quale organo gli effetti biologici, in relazione all'Indice Meccanico, potevano, con più probabilità, verificarsi; analogamente solo una minoranza conosceva l'unità di grandezza per l'Indice Termico. La maggioranza era a conoscenza di come i tessuti del feto siano più suscettibili ai potenziali effetti di quelli adulti. Pochi partecipanti conoscevano le raccomandazioni delle Società Internazionali di Ultrasonologia in campo di sicurezza. CONCLUSIONI: Lo studio ha fatto emergere come sia necessaria una maggior diffusione delle conoscenze sugli effetti biologici degli ultrasuoni tra gli ecografisti italiani.

We report a characterization of hard amorphous carbon films prepared by a new method: high-energy (ca. 30 keV) bombardment with CH 3 + and CH 4 + ions. The results of AES and EELS reveal that almost 60% of the atoms are in sp 2 sites and are consistent with the hypothesis that the microscopic structure of the films consists of an intricate network of small amorphous graphite-like sheets connected by sp 3 -rich zones. Raman spectroscopy and SIMS results are also discussed.

Deposition of diamond-like thin films has been achieved using mass-separated C+, CH+3 and CH+4 ion beams of energies between 1 and 40 keV. Characterization using different methods shows that the structure and physical properties of the films obtained are closer to those of diamond when 30–40 keV CH+3 or CH+4 ion beams are used. The hydrogen concentration, measured with elastic recoil detection analysis, is lower than 1 at.% for all the 30 keV hydrocarbon beams used.

A Monte-Carlo method is described for the analysis of the reliability/maintenance of complex systems. The methodology proposed adopts the formalism used in particle transport. The Monte-Carlo code SPAR is then presented, together with an application to a simple example to illustrate the potential of the method.

Aims: Portal venous thrombosis (PVT) is considered an absolute contraindication to liver transplantation (LT) in patients with hepatocellular carcinoma (HCC) when neoplastic PVT cannot be excluded. Aim of the study is to assess whether imaging techniques allow evaluation of nature of PVT in HCC-patients allowing safe selection of candidates to LT. Methods: We analyzed 34 HCC-patients with PVT detected at the time of assessment for LT or developed while on the waiting list. The benign nature of the thrombus was established using the following criteria: lack of vascularization of the thrombus at contrast enhanced ultrasound with SonoVue and ceCT or ceMRI, steadiness/regression of thrombosis during follow-up, absence of mass-forming aspects of PVT on ultrasound examination, absence of features of disruption of the vessel walls, and negative biopsy of the thrombus in case of uncertainty. Patients who did not fulfill the criteria for benignity of PVT were excluded from the waiting list. Results: The outcome of 34 patients analyzed is as follows: 13 were listed and transplanted, with no sign of malignant PVT at explant pathological examination; 9 were admitted in the list and are actively waiting. Two patients died for HCC unrelated causes while actively listed. Of the remaining 10 patients, 7 were not included or excluded from the list for the suspicion or confirmation of malignant PVT, whereas 3 were included and subsequently excluded for progression of HCC without evidence of malignant PVT. Conclusions: Imaging techniques allow safe not-invasive assessment of the nature of PVT in HCC-candidates to LT.

The aim of this study was to identify the most common patterns of various common liver lesions at real-time contrast-enhanced ultrasonography with second-generation contrast agents and their role in the differentiation of malignant from benign lesions.The enhancement pattern in the arterial phase and its modifications in subsequent portal and sinusoidal phases were separately evaluated in (i) 171 liver lesions detected at conventional ultrasonography in 125 noncirrhotic patients (87 metastases, six cholangiocellular carcinoma, 38 focal nodular hyperplasia, 30 hemangiomas, seven focal fatty sparing/changes, two hepatocellular adenomas and one hepatocellular carcinoma) and (ii) 75 lesions detected in 67 cirrhotic patients (66 hepatocellular carcinoma and nine dysplastic nodules). The final diagnosis was made by contrast-enhanced helical computed tomography and/or magnetic resonance imaging or by ultrasonography-guided biopsy when the diagnosis was equivocal at conventional imaging techniques (45 lesions).In noncirrhotic patients, the hypoechoic pattern in portal and sinusoidal phase (rapid washout) or the markedly hypoechoic or anechoic pattern in sinusoidal phase (marked late washout) showed a sensitivity, specificity and accuracy of 96.8, 100 and 98.2% for the diagnosis of malignancy. In cirrhotic patients, early arterial enhancement showed a sensitivity of 93.9% for the diagnosis of malignancy, with a specificity as low as 55.5% given the presence of arterial enhancement in 5/9 nodules resulted dysplastic at histological analysis.Real-time contrast-enhanced ultrasonography provides sensitive and specific criteria for the differential diagnosis between benign and malignant liver lesions, and in most cases it may replace more expensive and invasive imaging techniques.

Patients with liver disease or systemic pathology are more prone to develop portal vein thrombosis. Non-neoplastic thrombosis is characterised by absence of intrathrombotic perfusion, corresponding to marked hypoechogenicity at contrast-enhanced ultrasound. We report two cases of portal vein thrombosis in which contrast-enhanced ultrasound showed marked hypoechogenicity in the late phase. This late phase perfusional contrast pattern is consistent with non-neoplastic thrombosis, but is actually similar to that of metastatic liver lesions. Echo-guided needle biopsy indeed yielded histological results consistent with carcinoma. Repeated contrast-enhanced ultrasound showed presence of intratumoural perfusion in the arterial phase, suggestive of the neoplastic nature of the thrombus. Our cases suggest that CEUS with second generation contrast agents in patients with portal thrombosis should include the evaluation of both arterial and portal phases in order to provide accurate non-invasive diagnosis of metastatic portal vein thrombosis.

In the last years the incidence of hepatocellular carcinoma (HCC) is rising in cirrhotic patients worldwide. Due the importance of early and definite diagnosis of HCC, any nodular lesion detected in patients with chronic liver disease should be considered as suspicious for HCC. The screening and surveillance programs in patients with liver diseases have increased the number of small HCC detected at an early stage, when the therapeutic options available are able to provide benefit. The introduction of new imaging techniques has improved the accuracy of characterizing these nodules. According to the EASL recommendations, contrast-enhanced computed tomography (CT), contrast enhanced ultrasound (US) and magnetic resonance (MR) with different MR-contrast agents are currently used to characterize liver lesions. Imaging guided biopsy is recommended for small nodules or in lesions without typical features (arterial hypervascularization) in at least two imaging techniques. Frequently the differential diagnosis of small nodules is complicated by discordant vascularity and recent studies have also demonstrated the presence of small hypovascular HCC at perfusional US and helical CT. At present, different treatment options can be offered to patients with diagnosis of small HCC at an early stage; percutaneous techniques, surgical resection and liver transplantation can provide benefit in properly selected patients. This review describes some critical points regarding the detection, diagnosis and therapeutic management of small nodules of HCC in cirrhotic patients.

Objective: In chronic obstructive pulmonary disease (COPD) patients with acute respiratory failure (ARF), bronchodilating agents administered by inhalation have, in general, little effect on dynamic hyperinflation and concurrent static intrinsic positive end-expiratory pressure (PEEPi,st). Since in COPD the severely obstructed segments of the lung may not be reached by inhaled medication, we reasoned that drug efficiency may be enhanced by intravenous administration of the agent. Design: Physiological study. Setting: Two four-bed surgical-medical ICUs of a university hospital. Patients: Fourteen COPD patients were studied within 36 h from the onset of ARF. Measurements and results: Static compliance (Cst,rs), minimal (Rmin,rs) and additional (ΔRrs) resistance of the respiratory system, and PEEPi,st were measured before and after intravenous administration of salbutamol. All patients had limitation of air flow before and after salbutamol administration. On average, after salbutamol there was a small, though significant, decrease in Rmin,rs (-9%), ΔRrs (-12%) and PEEPi,st (-8%). Conclusion: The changes in resistance and PEEPi,st after intravenous administration of salbutamol were too small to be of clinical significance.

To evaluate the effects of major vascular surgery on respiratory mechanics, 11 patients undergoing general anaesthesia for abdominal aortic surgery were studied. Before aortic cross-clamping, chest wall elastance and resistance both increased (by 126% and 58%, respectively) when surgical retractors were placed. After aortic cross-clamping, lung elastance increased by 29%, accompanied by a decrease in cardiac index (22%) and an increase in pulmonary (17%) and systemic (15%) vascular resistance. After aortic unclamping, lung elastance decreased, although it remained higher than baseline values (by 12%). All cardiovascular variables returned to the values obtained before aortic cross-clamping.

To evaluate the effects of pharyngeal gas insufflation (PGI) in clinically stable patients with chronic obstructive pulmonary disease (COPD).Prospective study in humans.Department of Intensive Care Medicine at a University Hospital.Seven clinically stable COPD patients.Pharyngeal dry fresh air insufflation (PGI) with a continuous flow rate of 4 L/min was given via a nasal catheter placed into the oropharynx. Baseline measurements with zero flow were made at the beginning and end of the test. After an equilibration period of 1 h at each stage, arterial blood samples were analyzed every 5 min until PaCO2 variation less than 5% confirmed the achievement of a steady state. Thereafter expiratory flow signal and expiratory gas were collected over a period of 3 min and arterial blood was sampled after 1'30" and 2'30" from the beginning of the test for the measurement of effective expiratory volume (VE eff), respiratory rate (RR), tidal volume (VT), dead space fraction (VD/VT), dead space (VD), alveolar ventilation (VA), total expiratory time (TE min), and PaCO2, respectively.During PGI VT, VD/VT, VD and VE eff fell significantly from baseline values, RR was slightly reduced and VA, TE min and PaCO2 remained unchanged throughout the study.Although in our study the effect of PGI on VD could be overestimated since our device for expiratory gas flow measurement and collection significantly enlarged the anatomical dead space receiving the washout effect of the fresh gas insufflation, under the experimental conditions PGI produces a reduction in VD and VD/VT, and, as a consequence, a significative reduction in respiratory requirements in clinically stable COPD patients. If confirmed in clinical settings, potential advantages of PGI could include: a) reduction of the work of breathing in patients with intact neuro-respiratory coupling; b) minimizing hypercapnic side effects of oxygen therapy often seen in COPD patients.

Time resolved optical experiments on different molecular liquids in the proximity of disorder‐order phase transitions show the appearance of relatively slow collective dynamics associated to the set‐up of long range intermolecular correlation. The data are discussed on the basis of the available microscopic and phenomenological theories.

To collect valuable informations for the evaluation of the patients' clinical evolution and to perform a cost-effectiveness analysis on the utilization of resources in the management of patients with chronic obstructive pulmonary disease (COPD) undergoing mechanical ventilation (MV) for acute respiratory failure (ARF).General ICU. University Hospital.87 BPCO patients (mean age: 69.6 +/- 8.5) undergoing MV for ARF due to non surgical or traumatic events, for a total of 108 consecutive ICU admissions between January 1983 and December 1993.Retrospective study in which the following data were collected: severity of the underlying chronic respiratory disease before the occurrence of ARF. For this aim patients have been divided into five classes (O-IV) according with ATS classification of dyspnea; causes of ARF; SAPS score; TISS score; OMEGA score; complications occurred in ICU; duration of MV; duration of stay in ICU; ICU and hospital outcome.In 48 cases (44.4%) clinical history was positive for a severe dyspnea (classes III-IV). Slight airway flogosis or infection were responsible of ARF in 78 cases; pneumonia was present in 24 cases while in 6 cases ARF was due to congestive heart failure. The study population was divided into two groups according with outcome. No statistically significant difference was observed in mean SAPS and TISS scores between the two groups (12.5 +/- 3 vs 13 +/- 4.8 and 18.4 +/- 2.3 vs 19 +/- 4.2). Mean OMEGA score was 155 +/- 11.7 (ES). With reference to ICU outcome the utilization rate or resources was 72.15% with a mean loss of resources of 43.2. Compli-cations were manly due to airway infection (16 cases) which was responsible in one case of the patient's death. Overall incidence of complications was relatively low and five of them led to patients' death in ICU. Mean duration of MV did not differ between the two groups (13.4 +/- 11.7 vs 14.3 +/- 11.7) but it was significantly longer in those patients whose clinical history was positive for severe dyspnea (classes III and IV) than in patients without this report (16.6 +/- 14.9 vs 10.9 +/- 6.9; p0.05). Mean stay in ICU did not differ significantly between survivors and non-survivors (21.4 +/- 18.6 vs 19.7 +/- 13). ICU mortality rate was 6.48% (7 patients) and hospital mortality rate was 20.3% (22 patients).Our results demonstrate that hospital outcome in COPD patients with ARF requiring mechanical ventilation is quite good. Prolonged mechanical ventilation and--severity of underlying chronic respiratory disease do not affect significatively the prognosis. The high costs of the treatment of these patients are counterbalanced by a good efficiency of utilization of resources and appreciable clinical results.

The idiopathic monoclonal gammapathy is frequent in adult. In this age the gammopathy is persistent due to either malignant disorders or so called benign monoclonal gammopathy. This condition in infants and children is uncommon, but not exceptional and is usually of a transient nature. We describe two cases during infectious diseases.

An extensive analysis of the intermolecular forces in the chlorine crystal has been performed. Different models of the intermolecular potential, including anisotropic terms and electrostatic contributions from multipoles higher than quadrupole have been taken into account and tested for their ability to reproduce static and dynamical properties of solid chlorine. The inclusion of anisotropic dispersion forces reproduces correctly the orthorhombic unit cell. Anisotropic terms are required also in the short range repulsive atom-atom interactions to obtain a good fit to lattice frequencies and stability of the Cmca structure with respect to a hypothetical cubic phase. A tensor formalism, particularly convenient for dynamical calculations, is developed and used to describe angular dependent atom-atom interactions.

A differential cross-section of one-phonon inelastic incoherent neutron scattering has been calculated, based on the density of benzene phonon states weighted by the amplitudes of hydrogen atom vibration. The cross-section obtained has been convoluted with the apparatus function of the KDSOG-1 instrument (reactor IBR-I). The experimental scattering spectrum from a polycrystalline sample atT=80 K is compared with the calculated one.

The phonon side bands of the Raman forbidden bending and asymmetric stretching vibrations in crystalline carbon disulphide are discussed. The lattice dynamics has been treated using a model potential including anisotropic atom-atom interactions and electrostatic terms with point quadrupoles placed on the sulfur atoms. The Raman scattering cross sections has been calculated starting from a two-center representation of the molecular polarizability with two point polarizability tensors on the sulfur atoms. It has been found that the experimental Raman scattering can be satisfactorily explained as arising from non linear terms in the expansion of the crystal polarizability.

Infrared and Raman spectra of p-chloroaniline are reported and assigned for the low-frequency lattice region at 300 K and 78 K. The observed frequencies of the lattice modes are compared with those calculated using a semi-empirical intermolecular potential. The agreement is very good, so confirming the high degree of transferability of the atom-atom potentials. The equilibrium conditions are also well fulfilled by the potential. The total calculated crystal energy is −13.5 kcal mol−1.

A lattice dynamics calculation of the carbonyl sulphide crystal has been made using an atom-atom potential in the rigid body approximation. The phonon sideband of the intramolecular bending mode is discussed and compared with the phonon density of states. An intensity weighted density of states is obtained by calculation of the transition dipole moments from the ground state to two-phonon states of the type vibrational exciton + lattice phonon by expansion of the dipole operator to second order. It is shown that the bulk of intensity in the phonon sideband is borrowed by anharmonic coupling from the free exciton band. The anharmonic coupling is treated in a simplified way by a perturbation method.

Infrared and Raman spectra of succinic anhydride are reported in the 0 to 200 cm −1 region at 300 K. The observed frequencies of the lattice modes are compared with those calculated using an atom—atom potential and assigned. The influence of the dipole—dipole interaction has been calculated and shown to be important for this type of calculation in order to obtain satisfactory results for the energy as well as for the equilibrium conditions and frequencies of vibration.

Infrared spectra of p -bis/dimethylhydroxysilyl/benzene (PBDMHSB) were studied in solution, KI pellet and the oriented crystalline state. Raman spectra of this compound were measured in the solid phase and solution. An approximate assignment is given for the fundamental frequencies. Anomalous dichroism was observed for the CH out-of-plane vibrations of the benzene ring.

The refinement of atom-atom parameters for molecular crystals has been considered. A simple formalism is developed for reducing the time taken for numerical computations and ensures reliable results. This formalism consists in defining independent potential parameters and deriving physically meaningful relations between the parameters which refer to the 'mixed' atom-atom interactions and other parameters. This procedure was applied to four aromatic hydrocarbon crystals; however it can be generalized to any molecular crystal with any molecule with any number of heteroatoms.

From March 1982, 31 patients with stage IV non-oat cell lung cancer have been treated. Radiotherapy was given as three 2.00-Gy fractions on Days 1 and 2, 8 and 9, 22 and 23, and 29 and 30, for a total dose of 48 Gy over a 30-32-day treatment period. A three-drug combination of cyclophosphamide (400 mg/m2), doxorubicin (17 mg/m2), and methotrexate (15 mg/m2) was given on Days 3 and 24 and repeated thereafter every 21 days. Three of 31 evaluable patients (10%) achieved objective complete response and 18 of 31 (58%) achieved partial response (ie, regression of 50%-90%), while no change or disease progression was observed in ten of 31 (32%). The overall response rate in our study was 68%, which is a response much higher than other results in extensive disease. However, controlled trials will be necessary to definitively establish the superiority of this regimen to conventional trials. There was a significant shift of performance status towards higher values after treatment: 12 of the 27 patients classified in the 70-80 Karnofsky category before treatment moved to the higher category, 13 remained in the same status, and only two shifted to the worst category, indicating that the treatment had been effective in giving patients a better quality of life during their survival. The median survival was 35 weeks for the entire group of patients and 44 and 15 weeks for the responders and nonresponders, respectively. One of the primary findings of this pilot study was the ability to give one course of 12 Gy of radiation as multiple fractions per day during each of the first 2 weeks of treatment alternated with one course of chemotherapy, with most patients having very mild or no side effects. Giving multiple daily fractions greater than or equal to 4 hours apart permits the delivery of a large amount of irradiation over a short time period (ie, 1-2 days) within the limits of normal tissue toxicity. Increasing the recovery time of radiotherapy by alternation with chemotherapy offers the possibility of increasing the total radiation dose beyond the upper limits now considered feasible by conventional radiation schedules for induction therapy.(ABSTRACT TRUNCATED AT 400 WORDS)

Normally, in examining and processing failure reliability data, people apply the flat part of the “bathtube” curve; experience has verified that for many simple electric and electronic components such a distribution occurs: they are characterized by a long period with few and random failures. But experience has also verified that many types of components have not a constant hazard rate; f. e., normally mechanical components have a wearout characteristic and a continuously increasing hazard rate during all the life. Besides, if only two or three items are tested for a short time, little in the way of accurate quantitative conclusions can be drawn applying the classical statistics laws and assuming a bathtube distribution; bayesian methods may be taken into consideration, but these methods may be applied only when significative data on a set of similar items (components) is available; on the contrary we must remark that the preferred method to compute the reliability of an item is to consider the basic physics of the failure: it is, to predict the component failure rate in terms of a statistical variation of the physics parameters characterizing its operating conditions. On this subject. we must say that if one agrees to characterize a component by a hazard rate function and to evaluate the hazard parameters by testing. the result is a macroscopic model. Such a model is not concerned with what happens inside the black box containing the part but only with the statistics of the part performance. To delve inside the black box. one must postulate various hypotheses about the microscopic behaviour of the device and to prove validity; in this type of reliability model. the causes of the component failure are considered. We have called “physics models” this type of methods to process reliability data; they mainly consist of the following three basic steps: 1- Analysis of the physics laws characterizing the component(part) normal operation. 2- Singling out of the parameters of the above laws affected by stocastic variations in order to choose and to define the failure distributions to be applied. 3- Evaluation, on the basis of the material data and of the component characteristics. of the limit variation range of the parameters mentioned in point 2 in order to exactly evaluate the foreseen failure rate distribution of the component.