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Ligophorus satunensis n. sp. was collected from the bluetail mullet, Crenimugil buchanani (Bleeker, 1853), caught off Satun, Thailand, representing the first report of the Ligophorus species in Thailand. The new species is most similar to Ligophorus fenestrum Soo & Lim, 2012 in its fenestrated dorsal hamuli, a ventral bar with a long, bifurcated anteromedian protuberance (AMP) without lateral pieces, and a non-sclerotized vagina. However, it differs from the latter in its dorsal hamuli (up to two layers of fenestrations of the dorsal hamuli in L. satunensis n. sp. vs six layers in L. fenestrum), ventral hamuli (nonfenestrated vs fenestrated), penis (turning a full circle before reaching the genital pore vs turning less than half a circle), and its accessory piece (non-grooved basally and grooved distally vs simply grooved along its entire length). A single specimen, very similar to L. satunensis n. sp., obtained from the same host fish, which can be differentiated from the latter by a considerably shorter AMP of the ventral bar and a smaller and slender dorsal hamuli, is tentatively designated here as Ligophorus sp. Moreover, the phylogenetic trees constructed from the concatenated sequences of partial large-subunit nuclear ribosomal DNA (28S) and nuclear ribosomal internal transcribed spacer 1 (ITS1) regions support that L. satunensis n. sp. is a new species closely related to L. fenestrum.
Measurements in the infrared wavelength domain allow direct assessment of the physical state and energy balance of cool matter in space, enabling the detailed study of the processes that govern the formation and evolution of stars and planetary systems in galaxies over cosmic time. Previous infrared missions revealed a great deal about the obscured Universe, but were hampered by limited sensitivity.
SPICA takes the next step in infrared observational capability by combining a large 2.5-meter diameter telescope, cooled to below 8 K, with instruments employing ultra-sensitive detectors. A combination of passive cooling and mechanical coolers will be used to cool both the telescope and the instruments. With mechanical coolers the mission lifetime is not limited by the supply of cryogen. With the combination of low telescope background and instruments with state-of-the-art detectors SPICA provides a huge advance on the capabilities of previous missions.
SPICA instruments offer spectral resolving power ranging from R ~50 through 11 000 in the 17–230 μm domain and R ~28.000 spectroscopy between 12 and 18 μm. SPICA will provide efficient 30–37 μm broad band mapping, and small field spectroscopic and polarimetric imaging at 100, 200 and 350 μm. SPICA will provide infrared spectroscopy with an unprecedented sensitivity of ~5 × 10−20 W m−2 (5σ/1 h)—over two orders of magnitude improvement over what earlier missions. This exceptional performance leap, will open entirely new domains in infrared astronomy; galaxy evolution and metal production over cosmic time, dust formation and evolution from very early epochs onwards, the formation history of planetary systems.
To determine the characteristics of acute phase nystagmus in patients with cerebellar lesions, and to identify a useful indicator for differentiating central lesions from peripheral lesions.
Acute phase nystagmus and the appearance of neurological symptoms were retrospectively investigated in 11 patients with cerebellar stroke.
At the initial visit, there were no patients with vertical nystagmus, direction-changing gaze evoked nystagmus or pure rotatory nystagmus. There were four cases with no nystagmus and seven cases with horizontal nystagmus at the initial visit. There were no neurological symptoms, except for vertigo and hearing loss, in any cases at the initial visit. The direction and type of nystagmus changed with time, and neurological symptoms other than vertigo appeared subsequently to admission.
It is important to observe the changes in nystagmus and other neurological findings for the differential diagnosis of central lesions.
To evaluate the effectiveness of tympanostomy tube placement in controlling symptoms of intractable Ménière's disease.
Fifteen patients with intractable Ménière's disease underwent tympanostomy tube placement in the affected ear. Post-operative changes in vertigo attacks and hearing level were recorded, and were evaluated according to American Academy of Otolaryngology–Head and Neck Surgery criteria.
At 12 months after treatment, 3 patients (20 per cent) showed complete control of vertigo, 7 (47 per cent) showed substantial control and 2 (13 per cent) showed limited control; 3 patients (20 per cent) required other treatment. At 24 months after treatment, 7 patients (47 per cent) showed complete control of vertigo, 3 (20 per cent) showed substantial control and 1 (7 per cent) showed limited control; 1 patient required other treatment 15 months after tympanostomy tube placement.
There is no definite pathophysiological explanation for the effect of tympanostomy tube placement in reducing vertigo attacks. This treatment is not effective for all patients with intractable Ménière's disease. However, tympanostomy tube placement might be an additional surgical therapeutic option to consider prior to contemplating other, more invasive treatments.
A fully coherent free electron laser (FEL) seeded with a higher-order harmonic (HH) pulse from high-order harmonic generation (HHG) is successfully operated for a sufficiently prolonged time in pilot user experiments by using a timing drift feedback. For HHG-seeded FELs, the seeding laser pulses have to be synchronized with electron bunches. Despite seeded FELs being non-chaotic light sources in principle, external laser-seeded FELs are often unstable in practice because of a timing jitter and a drift between the seeding laser pulses and the accelerated electron bunches. Accordingly, we constructed a relative arrival-timing monitor based on non-invasive electro-optic sampling (EOS). The EOS monitor made uninterrupted shot-to-shot monitoring possible even during the seeded FEL operation. The EOS system was then used for arrival-timing feedback with an adjustability of 100 fs for continual operation of the HHG-seeded FEL. Using the EOS-based beam drift controlling system, the HHG-seeded FEL was operated over half a day with an effective hit rate of 20%–30%. The output pulse energy was
at the 61.2 nm wavelength. Towards seeded FELs in the water window region, we investigated our upgrade plan to seed high-power FELs with HH photon energy of 30–100 eV and lase at shorter wavelengths of up to 2 nm through high-gain harmonic generation (HGHG) at the energy-upgraded SPring-8 Compact SASE Source (SCSS) accelerator. We studied a benefit as well as the feasibility of the next HHG-seeded FEL machine with single-stage HGHG with tunability of a lasing wavelength.
Primate tourism is a recent and growing trend in primate-habitat countries. Many primate tourism operations are outgrowths of community-based conservation initiatives (Hill, 2002) and have been promoted for their potential to achieve conservation goals as well as financial and educational benefits for local communities. One of the earliest and most successful initiatives is the Mountain Gorilla Project in the Virunga Mountains (Harcourt & Stewart, 2007). Gorilla tourism has been credited with bringing an important source of foreign currency to impoverished nations, educational opportunities for local inhabitants, and even increased reproduction in gorilla groups used for tourism (Harcourt & Stewart, 2007; and see Goldsmith, this volume). However, the extent to which many primate tourist operations are meeting these goals is not clear. As a result, conservationists, who were generally enthusiastic and encouraging about establishing primate tourism operations, are sounding more cautious, noting specific examples in which tourism has harmed wild primates, and pointing out that we know little about the impact of tourism on most of the populations it targets (Butynski, 2001). Most agree that we need to do much more research to better understand the ways in which primate tourism affects primate health, behavior, and reproduction. Only then will we be able to make sound recommendations that maximize conservation goals and minimize harm. This chapter reviews some approaches to assessing the effects of tourism on primate populations, presents findings on some of the negative impacts of tourism on a population of Tibetan macaques, and offers several recommendations to reduce these negative impacts both in China and elsewhere.
To examine the clinical features, age and gender distribution of patients, treatment methods, and outcomes of benign paroxysmal positional vertigo.
This paper reports a review of 357 patients treated for this condition at a single institution over a duration of 5 years. Patients with posterior canal benign paroxysmal positional vertigo were divided into two groups: one group underwent the Epley manoeuvre and the other received medication. The lateral canal canalolithiasis patients were also divided into two groups: one underwent the Lempert manoeuvre and the other received medication. Lastly, the lateral canal cupulolithiasis patients were treated with medication and non-specific physical techniques.
Results and conclusion:
For patients with posterior canal benign paroxysmal positional vertigo, resolution time was significantly shorter in the Epley manoeuvre group than in the medication group. For the lateral canal canalolithiasis patients, resolution time was significantly shorter in the Lempert manoeuvre group than in the medication group. Resolution time was significantly longer in the lateral canal cupulolithiasis patients than in the other patients. The average age of patients increased with the number of recurrences, as did predominance in females. Average age and rate of sensorineural hearing loss were significantly higher in patients with intractable benign paroxysmal positional vertigo compared with those in the curable benign paroxysmal positional vertigo group.
To investigate what kinds of stimuli are effective in detaching otoconia from the cupula in three experimental models of cupulolithiasis.
Three experimental models of cupulolithiasis were prepared using bullfrog labyrinths. Three kinds of stimuli were applied to the experimental models. In experiment one (gravity), the labyrinth preparation was placed so that the cupula-to-crista axis was in the horizontal plane with the canal side in the downward position. In experiment two (sinusoidal oscillation), the labyrinth preparation was placed 3 cm from the rotational centre of a turntable, which was sinusoidally rotated with a rotational cycle of 1 Hz and a rotational angle of 30°. In experiment three (vibration), mechanical vibration was applied to the surface of the bony capsule around the labyrinth using a surgical drill.
In experiments one, two and three, the otoconial mass was respectively detached in 2 out of 10 labyrinth preparations, none of the labyrinth preparations, and all of the labyrinth preparations.
Vibration was the most effective stimulus for detaching the otoconia from the cupula in these experimental models of cupulolithiasis.
Pore sealing has become a critical issue for the implementation of porous low-k dielectrics and for realizing acceptable reliability performance of the interconnect. This study focuses on fabrication of ultra-thin, conformal and plasma resistant pore seal layer and on understanding parameters playing a role in sealing the surfaces of porous low-k films. It was found that 2.5 nm-thick pore seal layer shows a perfect toluene seal property for the porous low-k film whose pore radius is 1.48 nm. The pore seal layer still show a good toluene seal property after irradiation of He plasma at 250°C for 10 sec. The increments of dielectric constant by applying the pore seal layer and by the He plasma irradiation for 10 sec are 0.04 and 0.03, respectively. Interestingly, all of toluene seal property, refractive index of the bottom part of the film and dielectric constant started to deteriorate after irradiation of He plasma for 20 sec. It was suggested that when toluene seal property degrades, plasma would start diffusing into pores and both refractive index of the bottom part of the film and k value start to increase.
Carbon nanotubes (CNTs) have been considered as a promising interconnect material to replace the solder bump used in the flip chip package because of their special electrical, mechanical and thermal properties, which may promote both the performance and reliability of the flip chip packaging. In this paper, electrophoretic deposition (EPD) of CNTs on substrates has been demonstrated for the interconnect application. EPD is a simple, low cost and high throughput process that is capable to produce densely packed film with good homogeneity at low temperature. By altering the electric fields and deposition time during the EPD process, the thickness of the CNTs film could be controlled. In this study, multi-walled carbon nanotubes (MWCNTs) were successfully coated on the various substrates using the EPD method. A highly uniform CNTs microstructure film with thickness over 5 µm was achieved. In addition, the selective depositions of CNTs on the pre-defined bond pads to form CNTs bumps were also accomplished. By employing typical flip-chip bonding technique, high density CNTs bumps were aligned to form a test chip/host substrate interconnects. The electrical conductivity of the CNTs interconnects was carried out using four-point probe measurement. Reliable electrical contacts with linear relationship in the current-voltage (I-V) characteristic suggesting ohmic behaviour were attained. The overall resistances extracted were also relatively low. These superior electrical properties have demonstrated that the CNTs bumps deposited using EPD method is a viable way to serve as an alternative to current metal solder interconnects material such as Sn-Pb alloys. Hence, it offers a promising interconnect application in the quest for device miniaturization in microelectronic industry.
Package-induced failures for BEOL interconnects in sub-45nm technology nodes have drawn attention to the great silicon and packaging integration challenges introduced by the weak mechanical properties of ULK-containing metallization elements. Empirical data and modeling studies for a range of silicon and packaging factors at 20nm node reveal fundamental insights into susceptibility to damage and approaches for recovery. Analysis of increase in degradation as BEOL layouts evolve to finer dimensions points to understanding of changes that will enable continued device scaling.
Low-k dielectric films can be substantially damaged during plasma processing. High energy UV and VUV photons emitted by plasma play the key role in damaging the porous low-k films directly or indirectly by stimulating chemical reactions with radicals in plasma and plasma afterglow. The different ULK samples (k: 2.0-2.2, porosity: 30-50%, pore radius: 1-2 nm) were studied by exposing to five radiation sources at various wavelengths (VUV: 193 nm, 147 nm, 104-106 nm, 58.3 nm, and EUV: 13.5 nm). Time-spatial behavior of the ULK damage as a function of photons fluence was studied by FTIR spectroscopy and XRF analysis. It is shown that the degree of damage depends on wavelength of UV light. The major UV damage was observed at the wavelengths below 193 nm. The maximum damage corresponds to 147 nm while the degree of damage at 58.3 nm was much smaller. In the case of organosilicate (OSG) based ULK materials, the degree of damage, as a rule, increases with porosity. Organic low-k materials are damaged more than OSG at 193 nm, but at shorter wavelengths (147, 106, 58.3 and 13.5 nm) they are more stable than OSG. One-dimensional model for radiation absorption and dynamics of CH3 group destruction in ULK films was developed. The cross-sections of photons absorption and photo-stimulated Si-CH3 bond breaking in ULK films for 13.5 -147 nm wavelength range were derived from a combined experimental and modeling study. The obtained values allow to simulate the VUV/EUV induced modifications of low-k materials with different composition, to understand better the mechanisms of plasma damage and to generate ideas for controllable modifications of low-k materials.
Scaling effects on Cu microstructure, resistivity, dielectric materials, and electromigration (EM) and time dependent dielectric break down (TDDB) reliabilities for Cu interconnects were reviewed. A simple empirical model of Cu resistivity related to Cu line area was presented. Cu line microstructures containing small grains mixed with large bamboo grains in Cu damascene lines from technology nodes below 65 nm were observed. As predicted in previous work, the EM lifetime was found to degrade by about 50% for every new generation even for the same current density. The Cu grain size was found to have a large impact on pure Cu and Cu alloy EM lifetime and activation energy Ea. Ea for pure Cu line capped with selective electroless CoWP on near-bamboo, bamboo-polycrystalline, to polycrystalline only line grain structures was reduced from 2.2 eV to 1.7 eV to 0.75 eV, respectively. Ea for 40 nm wide bamboo-polycrystalline lines capped with selective chemical vapor deposition (CVD) Co was found to be 1.7 eV. Using pure Cu and Cu(Al) or Cu(Mn) diluted impurity seed layers in 40 nm wide, bamboo-polycrystalline microstructure lines and above 100 nm wide, near bamboo-like grained lines, Cu-alloy lines enhanced EM lifetimes and increased QEM from 0.9 to 1. eV and 1.0 to 1.2 eV, respectively, compared to pure Cu lines. Inter-level TDDB testing on vias connecting M1 to M2 with a via chamfer angle that varied from 58o to 81o have very similar performance with intra-level M2 data with no vias tested at the same field. This result combined with the data from a separate study, which allowed the chamfer path to be isolated from the M2-level path, suggested that the failure took place preferentially along the weak cap/ILD interface at M2 and not at the via chamfer. TDDB acceleration data indicated that the root E model was overly conservative and a more aggressive model provided a better fit to the data. TDDB lifetimes correlated fairly well with the percentage of porosity in the dielectric materials.
We describe a mass transport TCAD simulation by using a Sentaurus S-Interconnect tool  that models reported electro-migration (EM) behaviors: EM induced resistance (R) change, line length (L) effect, and temperature (T) dependency on L and current density (j) products. We performed trend and sensitivity analyses for key physical EM model parameters: Cu-void formation, a sudden jump in line R associated with void growth, and Cu-vacancy (Cv) and void (Cvoid) profiles. In this manner, we develop a new methodology for accurately determining the EM lifetime by identifying an “EM-aware” region to define the L dependence of Cu-lines under high current stress. This includes electron flow dependency to explain line and via depletion effects for void formations under various stress conditions. We report a non-linearity in the L dependence on the jL product and a slight temperature dependence on the Blech Threshold (jL)c.
Monitor of All-sky X-ray Image (MAXI) on board International Space Station is capable of
observing gamma-ray bursts (GRBs) and sending notices of GRBs or other transient events,
using real time connection to the ground. MAXI observed 32 GRBs or short X-ray transients
as of the end of September 2012. Among them, eleven events were simultaneously detected by
other satellites. The observed rate of the MAXI GRBs is about one event per month. This
rate is comparable to a past observation with larger effective area and larger field of
view. The fact indicates that MAXI has better sensitivity to observe GRBs because of low
background. The distribution of the spectral hardness of MAXI GRBs is similar to the
results of a past instrument, which is sensitive to similar energy range.
This study demonstrates that thin metallic oxide layers, such as OsOx and ZnO, function as a strong adhesion layer between Cu film and glass substrate. The adhesion strength was studied with a micro-scratch tester and the films and interfaces were characterized by energydispersive X-ray spectrometry. The presence of an extremely thin intermixing layer was confirmed at the metal/glass interfaces. The formation of such an interfacial layer increased the adhesion strength significantly.
This paper describes an alternate two-step metallization scheme for porous dielectrics. The patterned dielectric surface is first treated in a plasma etch chamber where the dielectric surface is coated with a very thin carbon-based film. This is followed by electroless copper deposition. The plasma post-etch treatment (PET) film seals the pores of the dielectric, minimizes dielectric damage, and functionalizes the dielectric to enable electroless plating.
In this work, a novel low dielectric constant (low-k) pore sealing approach was engineered by depositing firstly a sub-2 nm SAMs and then a 3 nm TiN barrier film. The low-k film was pretreated by plasma to introduce hydroxyl groups onto the surface, followed by SAMs deposition. Then a TiN film was deposited from tetrakis(dimethylamino)titanium (TDMAT) via ALD as a dielectric barrier. Penetration of Ti atoms into low-k was measured and used to evaluate the sealing ability of SAMs. For the samples covered with SAMs, around 90% reduction of Ti atoms penetration was achieved. The pore radius was reduced to below 0.5 nm after the barrier deposition. The ∆k after pretreatment and after SAMs are 0.1 and 0.16, respectively.
Power consumption and dissipation during electrical operation lead to a temperature rise in the package. Elevated temperature in the package structure induces thermo-mechanical stresses which may increase reliability risks. Robust and reliable package design for power systems requires comprehensive analysis of system electrical, thermal, and mechanical behavior. This paper presents a self-consistent approach for package reliability analysis with coupled electro-thermal and thermo-mechanical modeling using TCAD tools.