Teaching evaluation: a complicated issue

To justify/quantify/qualify on teaching evaluation may be difficult and not objective as there are so much variables. Comparing teaching evaluations obtained by individual lecturer may not be meaningful, as each staff facing independent course with different students, course and other variables (or statistically, each is an independent event and a single mean value must not be compared directly with another)

POSTURAL EFFECTS ON COMPARTMENTAL VOLUME CHANGES OF BREATHING BY OPTOELECTRONIC PLETHYSMOGRAPHY IN HEALTHY SUBJECTS

Breathing pattern was an important factor to affect the performance of sports for athletes. Optoelectronic plethysmography (OEP) was a new method to evaluate breathing pattern by measuring compartmental volume (upper thorax (UT), lower thorax (LT), and abdomen (AB)) freely without limitation. Previous study already investigated the swimmers had better breathing pattern measured by OEP (Karine et al., 2008) in sitting posture. Swimming, such as backstroke, is perfromed in supine posture, but previous study did not consider the postural effect on breathing pattern. This study explored the compartmental volume changes of healthy subjects in different postures

Hamiltonian Formalism of the de-Sitter Invariant Special Relativity

Lagrangian of the Einstein's special relativity with universal parameter $c$ ($\mathcal{SR}_c$) is invariant under Poincar\'e transformation which preserves Lorentz metric $\eta_{\mu\nu}$. The $\mathcal{SR}_c$ has been extended to be one which is invariant under de Sitter transformation that preserves so called Beltrami metric $B_{\mu\nu}$. There are two universal parameters $c$ and $R$ in this Special Relativity (denote it as $\mathcal{SR}_{cR}$). The Lagrangian-Hamiltonian formulism of $\mathcal{SR}_{cR}$ is formulated in this paper. The canonic energy, canonic momenta, and 10 Noether charges corresponding to the space-time's de Sitter symmetry are derived. The canonical quantization of the mechanics for $\mathcal{SR}_{cR}$-free particle is performed. The physics related to it is discussed.Comment: 24 pages, no figur

An analytical model for input-buffered optical packet switches with reconfiguration overhead

The overhead associated with reconfiguring a switch fabric in optical packet switches is an important issue in relation to the packet transmission time and can adversely affect switch performance. The reconfiguration overhead increases the mean waiting time of packets and reduces throughput. The scheduling of packets must take into account the reconfiguration frequency. This work proposes an analytical model for input-buffered optical packet switches with the reconfiguration overhead and analytically finds the optimal reconfiguration frequency that minimizes the mean waiting time of packets. The analytical model is suitable for several round-robin (RR) scheduling schemes in which only non-empty virtual output queues (VOQs) are served or all VOQs are served and is used to examine the effects of the RR scheduling schemes and various network parameters on the mean waiting time of packets. Quantitative examples demonstrate that properly balancing the reconfiguration frequency can effectively reduce the mean waiting time of packets

A latency-aware scheduling algorithm for all-optical packet switching networks with FDL buffers

Optical buffers implemented by fiber delay lines (FDLs) have a volatile nature due to signal loss and noise accumulation. Packets suffer from excessive recirculation through FDLs, and they may be dropped eventually in their routing paths. Because of this, packet scheduling becomes more difficult in FDL buffers than in RAM buffers, and requires additional design considerations for reducing packet loss. We propose a latency-aware scheduling scheme and an analytical model for all-optical packet switching networks with FDL buffers. The latency-aware scheduling scheme is intended to minimize the packet loss rate of the networks by ranking packets in the optimal balance between latency and residual distance. The analytical model is based on non-homogeneous Markovian analysis to study the effect of the proposed scheduling scheme on packet loss rate and average delay. Furthermore, our numerical results show how various network parameters affect the optimal balance. We demonstrate quantitatively how to achieve the proper balance between latency and residual distance so that the network performance can be improved significantly. For instance, we find that under a given latency limit and light traffic load our scheduling scheme achieves a packet loss rate 71% lower than a scheduling scheme that ranks packets simply based on latency

Genome-wide analyses of Liberibacter species provides insights into evolution, phylogenetic relationships, and virulence factors.

'Candidatus Liberibacter' species are insect-transmitted, phloem-limited α-Proteobacteria in the order of Rhizobiales. The citrus industry is facing significant challenges due to huanglongbing, associated with infection from 'Candidatus Liberibacter asiaticus' (Las). In order to gain greater insight into 'Ca. Liberibacter' biology and genetic diversity, we have performed genome sequencing and comparative analyses of diverse 'Ca. Liberibacter' species, including those that can infect citrus. Our phylogenetic analysis differentiates 'Ca. Liberibacter' species and Rhizobiales in separate clades and suggests stepwise evolution from a common ancestor splitting first into nonpathogenic Liberibacter crescens followed by diversification of pathogenic 'Ca. Liberibacter' species. Further analysis of Las genomes from different geographical locations revealed diversity among isolates from the United States. Our phylogenetic study also indicates multiple Las introduction events in California and spread of the pathogen from Florida to Texas. Texan Las isolates were closely related, while Florida and Asian isolates exhibited the most genetic variation. We have identified conserved Sec translocon (SEC)-dependent effectors likely involved in bacterial survival and virulence of Las and analysed their expression in their plant host (citrus) and insect vector (Diaphorina citri). Individual SEC-dependent effectors exhibited differential expression patterns between host and vector, indicating that Las uses its effector repertoire to differentially modulate diverse organisms. Collectively, this work provides insights into the evolution of 'Ca. Liberibacter' species, the introduction of Las in the United States and identifies promising Las targets for disease management

Silicon Pad Detectors for the PHOBOS Experiment at RHIC

The PHOBOS experiment is well positioned to obtain crucial information about relativistic heavy ion collisions at RHIC, combining a multiplicity counter with a multi-particle spectrometer. The multiplicity arrays will measure the charged particle multiplicity over the full solid angle. The spectrometer will be able to identify particles at mid-rapidity. The experiment is constructed almost exclusively of silicon pad detectors. Detectors of nine different types are configured in the multiplicity and vertex detector (22,000 channels) and two multi-particle spectrometers (120,000 channels). The overall layout of the experiment, testing of the silicon sensors and the performance of the detectors during the engineering run at RHIC in 1999 are discussed.Comment: 7 pages, 7 figures, 1 table, Late

Differences in the Fine Motor Performance of Children in Hong Kong and the United States on the Bruininks-Oseretsky Test of Motor Proficiency

ObjectiveCross-cultural differences in motor development is an important issue for occupational therapists to address in the assessment process. The cultural variability of performance in scores interpretation can mislead therapists in their decisions regarding the need for intervention. This study aimed to investigate the differences in fine motor performance on the Bruininks-Oseretsky Test of Motor Proficiency (BOTMP) between school-aged children of Hong Kong and the United States.MethodsThe four fine motor subtests of the BOTMP were administered to a random sample of 264 Hong Kong children aged 6–10 years. The performance scores of participants were compared with those of the American normative samples.ResultsNo significant difference was found in the scores between the two groups in Upper Limb Coordination and Response Speed subtests. However, the Hong Kong children performed significantly better in the subtests of Visual-Motor Control and Upper Limb Speed and Dexterity. In addition, significant gender difference was also present in all subtest scores except for the subtest of Upper Limb Speed and Dexterity.ConclusionThe results suggest that occupational therapists should be cautious of cross-cultural differences when interpreting fine motor performance scores using the BOTMP for Hong Kong school- aged children