دانلود گزارش کارورزی و کار آموزی

چکیده : 

One widely acknowledged benefit of group living is an increase in the efficiency of predator avoidance.

Experiments have demonstrated a variety of mechanisms involved, such as ‘the selfish herd’. In this

experiment we exposed groups of two-spot astyanax, Astyanax bimaculatus, to three predatory stimuli

(‘active search’, ‘avian pecking’ and ‘sit-and-wait’) and one nonpredatory control stimulus. In response to

these stimuli we found that fish were more likely to chase and attack a group member when exposed to

an active search predator model. This response was not observed for the control or the other predators.

This response could reduce an individual’s predation risk by making the other (i.e. the attacked) individual

more vulnerable to predation. We showed that this trait was an innate response and as such a

result of natural selection rather than a learning process. This study shows how group living may result

in active selfishness, an additional cost of group living

چکیده : 

Background: Recent research suggests that Tourette’s syndrome (TS) may result from a defect

in the dopamine system. Several candidate gene polymorphisms have been implicated in

attention deficit hyperactivity disorder, including the dopamine transporter (DAT1) and

dopamine b-hydroxylase (DBH) genes. A high rate of comorbidity between attention deficit

hyperactivity disorder and TS indicates that they may share the same pathophysiology.

Purpose: We aimed to test the hypothesis that the dopamine gene might play a role in TS.

Methods: An association study, using an independent sample of patients from the midland

region of Taiwan, was performed to investigate whether DAT1 and DBH gene polymorphisms

can be used as markers of susceptibility to TS. A total of 160 children with TS and 83 normal

control participantswere includedin the study. Polymerase chainreactionwas usedto identify

polymorphisms in the DAT1 (40 bp VNTR) and DBH (TaqI A2) genes. Genotypes and allelic

frequencies for the DAT1 and DBH gene polymorphisms in both groups were compared.

Results: The results showed that genotypes and allelic frequencies in both groups were

not significantly different. The most common genotype for DAT1 (40 bp VNTR) was the

10,10 homozygote in both groups. The most common genotype for DBH (TaqI A2) was the

T homozygote in both groups.

Conclusion: These data suggest that the DAT1 and DBH genes may not be useful markers to

predict susceptibility to TS.

چکیده : 

Background: Parkinson’s disease (PD) is characterized by progressive neuronal cell loss and

decline in movement. Recently, much attention has been focused on the dopaminergic

neurotoxicity, which causes neurogeneration in the nervous system, thus implicating

dysfunction in predisposition to PD pathogenesis. b-glucosidase (GBA), the enzyme deficient

in Gaucher’s disease, has been cited as linked with Parkinson’s disease. We investigated

whether GBA mutation is associated with PD patients in middle Taiwan.

Methods: GBA mutation was detected by polymerase chain reaction and sequencing in 148

patients with PD and 120 normal controls.

Results: The results revealed a significant difference between PD patients and normal

controls in GBA mutation and a statistic correlation between GBA mutation L444P and PD

formation. It could be concluded that patients who carry the T/C of GBA mutation, L444P,

have a higher risk of developing PD in Chinese patients in middle Taiwan.

چکیده : 

Rabies is a widespread zoonotic disease responsible for approximately 55,000 human deaths/year. The

direct fluorescent antibody test (DFAT) and the mouse inoculation test (MIT) used for rabies diagnosis,

have high sensitivity and specificity, but are expensive and time-consuming. These disadvantages and

the identification of new strains of the virus encourage the use of new techniques that are rapid, sensitive,

specific and economical for the detection and research of the Rabies Virus (RABV). Real-time

RT-PCR, phylogeographic analysis, proteomic assays and DNA recombinant technology have been used

in research laboratories. Together, these techniques are effective on samples with low virus titers in the

study of molecular epidemiology or in the identification of new disease markers, thus improving the

performance of biological assays. In this context, modern advances in molecular technology are now

beginning to complement more traditional approaches and promise to revolutionize the diagnosis of

rabies. This brief review presents some of the recent molecular tools used for RABV analysis, with

emphasis on rabies diagnosis and research.

چکیده :

Background: Obesity is one of the main causes of preventable death. Complications of

childhood obesity include cardiovascular risk, impaired glucose tolerance, type 2 diabetes

mellitus, and acanthosis nigricans (AN; associated with obesity as a manifestation of

cutaneous insulin resistance). An interaction between AN and obesity as well as a detailed

mechanism for the pre- and co-obesity appearance of AN in children are still to be

revealed.

Purposes: This research tries to assess involvement of the insulin/insulin-like growth factor

(IGF) receptor pathway in childhood pre- and co-obesity AN via a study of the association of

polymorphisms of the INSR, IRS1, and IGF1R genes with pre- and co-obesity AN.

Methods: In total, 99 children with pre- and co-obesity AN and 100 healthy controls were

genotyped and analyzed by the polymerase chain reaction-restriction fragment length

polymorphism method.

Results: Intergroup frequency differed starkly for INSR His1085His and IGF1R IVS7-20, but

not in the IRS1 Ala804Ala or IGF1R Thr766Thr genotypes. The T allele of INSR His1085His

and C allele of IGF1R IVS7-20 both conferred a starkly( p¼0.04 and 2.84E-6 ¼ 2.84 x 106,

respectively)higher risk for AN.

Conclusion: The above findings suggest that certain genetic variants in insulin/insulin-like

growth factor (IGF) receptor pathway might be correlated with the appearance of AN prior

to or concurrent with obesity, and also reveal the insulin/IGF receptor pathway as crucial in

pre- and co-obesity AN.

چکیده : 

Weconstruct a Schrödinger-like equation for the longitudinal wave

function of a meson in the valence q¯q sector, based on the ’t Hooft

model for large-N two-dimensional QCD, and combine this with

the usual transverse equation from light-front holographic QCD,

to obtain a model for mesons with massive quarks. The computed

wave functions are compared with the wave function ansatz of

Brodsky and de Téramond and used to compute decay constants

and parton distribution functions. The basis functions used to

solve the longitudinal equation may be useful for more general

calculations of meson states in QCD.

چکیده : 

We study bipartite quantum discord as a manifestation of a multipartite

entanglement structure in the tripartite purified system.

In particular, we find that bipartite quantum discord requires the

presence of both bipartite and tripartite entanglement in the purification.

This allows one to understand the asymmetry of quantum

discord, D(A, B) ̸= D(B, A) in terms of entanglement monogamy.

As instructive special cases, we study discord for qubits and Gaussian

states in detail

چکیده : 

We study localization properties of disordered bosons and spins

in random fields at zero temperature. We focus on two representatives

of different symmetry classes, hard-core bosons (XY magnets)

and Ising magnets in random transverse fields, and contrast

their physical properties. We describe localization properties using

a locator expansion on general lattices. For 1d Ising chains, we

find non-analytic behavior of the localization length as a function

of energy at ω = 0, ξ−1(ω) = ξ−1(0) + A|ω|α, with α vanishing

at criticality. This contrasts with the much smoother behavior predicted

for XY magnets. We use these results to approach the ordering

transition on Bethe lattices of large connectivity K, which mimic

the limit of high dimensionality.

چکیده : 

Zero-energy wave packets, coherent states, are constructed in such

a way that they retain their shape during the time evolution for a

large class of central potentials. The packets are not of the Gaussian

type with −r2 dependence but, instead, their shape is determined

by−r

1

μ+1/2 with−1/2 < μ < 1/2. A very close quantum–classical

correspondence is also shown, i.e., the well localized states travel

along suitable classical trajectories.